This document summarizes a patent for improving the impregnation of sheet materials with synthetic resin latices. Specifically, it describes a two-step process of first impregnating a fibrous sheet material with an aqueous latex containing vinyl resin particles and an anionic surfactant. The second step involves treating the impregnated material with an aqueous solution of a polyvalent metal salt to coagulate the resin particles. This allows the material to be stiffened when later treated with a solvent for the resin. The summary provides the key steps and purpose of the patented impregnation process.

1. * GB785058 (A)
Description: GB785058 (A) ? 1957-10-23
Improvements in or relating to the impregnation of sheet materials with
synthetic resin latices
Description of GB785058 (A)
A high quality text as facsimile in your desired language may be available
amongst the following family members:
DE1024481 (B) FR1139582 (A) US2760884 (A) FR1139583 (A)
DE1024481 (B) FR1139582 (A) US2760884 (A) FR1139583 (A) less
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PATENT SPECIFICATION
-785,058
Date of Application and filing Complete Specification: March 25, 1955.
No 8872155.
Application made in United States of America on July 22, 1954.
: Complete Specification Published Oct 23, 1957.
Index at Acceptance:-Classes 17 ( 2), B 9 A; and: 140, P 3 (E: F 4: G
5).
International Classification:-A 43 b, 'D 06 b.
COMPLETE SPECIFICATION A, Improvements in or relating to the
Impregnation of Sheet Synthetic Resin Latices.
Materials with ERRATU% SPECIFICATION NO 785,058
Page 5, line 69, for " 30 0 % by weight of an Inlonlc" read " 3 O % by
weight of an anlonlc".
THE PATENT OFFICE, 18th November, 1957 material with finely divided

2. particles of cellulose nitrate After drying this product was stored
until ready for use, at which time the impregnated flannel was dipped
into a solvert for 'the cellulose nitrate, applied to the appro-.
priate shoe part and allowed to dry in a stiffened condition It is
also known that sheet material such as flannel may be impregnated by
dipping the flannel into an aqueous dispersion of synthetic resin,
such as a synthetic rubber latex However in all the known
processes-there are operating difficulties which arise because of the
tendency of such a latex to deposit in the form of a dense impervious
layer As a result of forming such a layer the porosity of the
impregnated material is low and the ability of the material to absorb
solvents is poor The low porosity and, poor solvent absorption
prevents the achievement of thie greatest stiffnes's for a given
composition of impregnated, fabric Therefore to obtain a' desired
stiffness, according to known processes, heavier, 'flannels or other
supporting materials, must be impregnated with a greater amount of
xesin, and such pro,A cedures are commercially unattractive.
In our'United Kingdoni Patent Specifica:;' tion No 766,866 there is
disclosed and lPrice 3 s6 d l DB 00801/2 (e) /3603 150 11/57 R resin
latex impregnation This process, in general, involves dipping a sheet
material into an aqueous bath containing a vinyl, or vinylidene
polymer or copolymer, a water ' soluble polyvalent metal salt, and a'
non-ionic 65 dispersing agent which is water-soluble at room
temperatures and up to about 40 C and insoluble at higher temperatures
The, impregnated sheet is heated to a temperature of C to'120 C,
causing the dispersing agent 70 to become insoluble and thus allowing
coagulation to take place The impregnated sheet material prepared in
this manner contains uniformly dispersed agglomerates of synthetic
resin particles and the sheet material is 75 dry, flexiblie and easy
to handle or to store.
The present invention is an alternative procedure to that described
and 'claimed in Specification No 766,866 The present ii vention
provides' a two-step process for 80 impregnating a fibrous sheet
material: 'with ( 1) an aqueous latex containing dispersed vinyl resin
solids 'and,an anionic sirface-active wetting agent and ( 2) a
coagulent for the dis persed resin solids in the form of an aqueous 85
solution of a polyvalent minetal salt to produiace a sheet material
capable of being stiffened by treatment with a solvent for the resin
In the h -7 "_x _ ±',,.
-PATENT S Pi ECIFCATION:"
,; Lf a " ':'::: a ls' ", ' ""'-'" " -" Index at A:"epta-ce::
1-Classes 17 ( 2), BA'; and:'140, P 3 (E: s'),:' ' ' ':'' ' ' -0-).
Internatiomal"Classi catibn; 7 43 b,:'DOO,,":l: " M Nao 5887 ? 2/55 '
-, A t;;;g Y: Apphcation made in United States of America on July 22

3. >,954 k ^ W ffi t Comp fete Speciflcdtioh Published Oct 23, 1957 ' ' '
'; '-' Index -at Acceptance:-Classes 17 ( 2), B 9 A; and10 1 3 E 4 (-:
International C 1 assificatfon 7-4 b: 'D 06 j,,40, P-( F 4, ' .: -;'
-COMPLETE SPECIFICATION::' '''
Improvements in or relating to the Impregnation of Sheet Materials
with Synthetic Resin Latices We,,THE CELASTIC CORPORATION, a Cor
claimed a process whereby,certain relatively 45 poration organized and
existing uinder the laws cheap synthetic resin latices may be imof the
State,,of Dejaware, United States of pregnated in the form of finely
divided parAmnerica,, located at Arlington, New Jersey, tides into, a
flanne L sheet inaterial, which has-a United States of America, do
hereby declare long storage life, and which may thereafter be ' the
invention, forwhich we pray that a patent treated with a solvent
for'the synthetic resin, 50 may be granted to us, and the method by
applied to the shoe part, and allowed to dry which it is to be,
performed, to be particularly and form a high -quality shoe stiffener
-The described in and by the following statement:, sheet material
utilized in the process of, the l O This inventionrelates to
amethod-of stiffen said Specification No 766,866 may be of-the n::
ing a fibrous,,sheet material, and' more par lightest -grade and yet
be impregnated, with 55 ticularly it relates to -a method of preparing
sufficient resin to be stiffened to a very high shoe stiffeners,by
treating a sheet material degree, because -the process produces a
hilhy'with a synthetic resin latex porous' impregnated fabric having
the ability High, quality, shoe stiffeners in the past have to absorb
larger percentages of solvhrent than c been made by 'im pregnating a
flannel sheet has ever been achieved by the use of synthetic 60
material with finely divided particles, of cellu resin latex
impregnation This process, in lose nitrate After, drying this product
was general, involves dipping a sheet material into stored untii ready
for use, at which time the a aqueous bath ontaining a vinyl, or
impregnated flannel was dipped into a solvent vinylidene polymer or
copolymer, a water l.
for'the cellulose nitrate, applied to the appro soluble polyvalent
metal salt, and a' non-ionic 65 priate shoe part and allowed - to dry
in a dispersing agent which is water-soluble at stiffened condition
she room temperatures and up to about 40 C and It is also known that
sheet material such as insoluble at higher temperatures The imflannel
may be impregnated by dipping the pregnated sheet is heated to a
temperature of flannel into an aqueous dispersion of synthetic 40 C
to'120 C, causing the dispersing agent 70 resin, such as a synthetic
rubber latex However to become insoluble and thus allowing in all the
known processes-there are operating coagulation to take place The
impregnated difficulties which arise because of the tendency sheet

4. material prepared in this manner conof such a latex to deposit in the
form of a tains uniformly dispersed agglomerates of syndense
impervious layer As a result of forming thetic resin particles and the
sheet material is 75 such a layer the porosity of the impregnated dry,
flexible and easy to handle or to-store.
material is low and the ability of the material The present,invention
is an alternative proto absorb solvents is poor The low porosity
cedure to that described and claimed -in and poor solvent absorption
prevents the Specification No 766,866 The present inachievement of the
greatest stiffness for a given vention provides: a two-step process
for 80 composition of impregnated fabric Therefore impregnating a,
fibrous sheet material 'with to obtain a desired stiffness, according
to ( 1) an aqueous Iatex containing dispersed known processes, heavier
flannels or other vinyl, resin solids'and ani anionic surface-active
supporting materials, must be impregnated wetting agent and ( 2) a
coagulent for the diswith a greater amount of resin, and such pro
persed resin solids in the form-of an aqueous 85 cedures are
commercially unattractive solution of a polyvalent metal salt to
produce a In our'United Kingdom Patent Specifica sheet material
capable of being stiffened by tion No 766,866 there is disclosed and
treatment-with a solvent for the resin In the lPrice 3 s6 d l UED M 2
Cij 2: : A 7855058 -present process the sheet material 'is im-' 'tibn
and, at least partially, dried, and then pregnated&with a resin latex
in one step and impregnated with the resin latex, stripped and
-freated' with coagulant in a separate step The dried In still a third
embodiment, a creamed order of treatment is immaterial, and there
latex is prepared by adding to the above-' fore the
sheet'-materialmay:bb -impregnated ' described resin latex enouglf
coagiilant salt to 70 with latex either before or after the sheet
cause the watery latex to coagulate partially material is contacted
with the latex coagulant and to have a creamy consistency Thie
fibrous:
The latex particles are agglomerated irmme sheet material is first
impregnated with this diately upon contact with the coagulant in the
creamed latex, stripped, and then impregnated present process, while
in the process of the with a dilute coagulant solution and dried 75
copending application agglomeration does not Each of the above methods
produces a dry, occur until the impregnated material is heated
flexible, sheet material impregnated with resin It is an object of
this invention to provide a agglomerates, and this material, after
drying, novel method for stiffening fibrous materials may be stored
for long periods of time without It is another object of this
invention to prepare suffering harm due to chemical or physical 80
high quality shoe stiffeners by using a synthetic change This material

5. is capable of being resin latex as the impregnating medium It is
stiffened by treatment with a volatile solvent still anotherobject to
provide a two-step pro-: for:the resin Upon evaporation lof the
solvent, cess for impregnating fibrous sheet materials the-shleet
material stiffens.
which are capable of being stiffened by sub In the preferred
embodiment of this inven 85 sequent solvent treatment tion an
impregnating medium is prepared by The above objects are accomplished
in mixing at room temperature, 3 parts by weight accordance with the
process of -this invention of an -aqueous polystyrene latex
contaifiing by impregnating a fibrous sheet material with 50 % solids,
1 part of an aqueous latex of a an aqueous latex of a synthetic vinyl
resin The copolymer of -styrene and butadiene' (in the 90 sheet
material may be treated prior to the approximate proportion of 80
parts styrene to above-latex impregnation 'step -with a poly 20 parts
butadiene) containing 45 %' solids, and.
valent metal salt coagulant, or the sheet 1 % by weight of resin
solids of an anionic material may be treated with a solution of such
surface-active organic phosphate or sulfonate a coagulant by a
step-subsequent to' the latex as a wetting agent The desired sheet
material 95 impregnation step The aqueous resin latex is then dipped
into this latex and stripped of comprises from 20 % to 60 % by weight
'of excess liquid by passing between closely spaced vinyl resin
particles and at least 0 10 % and rolls The sheet material is then
dipped into a preferably not more than 3 0 % by weight of second bath
containing aluminium isulfate, in an anionic surface-active wetting
agent This the form of a'1 % aqueous solution -Agglomera 100 amount of
wetting 'agent is equivalent to 0 5 % tion of the resin solids takes
place within the to 5 0 % by weight of the resin solids present sheet
material at this time The material is In a step separate from the
above latex irm then dried in air at '100 C and there is pregnation
the fibrous sheet material is con-' recovered a dry, flexible,
impregnated sheet tacted with an aqueous solution of a polyvalent
material containing 60 % to '70 % or more'105 metal salt, -normally in
the form of a 5 %' resin solids in the form of small 'agglomerates
aqueous solution Whether the coagulant is dispersed throughout the
sheet material.
applied prior to or subsequent to the latex im Because of these
agglomerates the sheet pregnation, the resin solids agglomerate immoe
material is -highly porous and is capable of diately upon contact
between the coagulant and absorbing a large amount of resin solvent
which 110 the resin particles The agglomeration takes in turn is the
principal factor permitting the place in the interstices of the
impregnated achievement of a high degree of stiffness in the material

6. forming resin agglomerates in situ impregnated sheet miaterial After
the sheet material has been impregnated When this impregnated material
is ready for with the latex and the-coagulant, -it is dried, use as a
stiffener, it is blanked into the desired 115 for example, in an air
oven at 100 C, to form shape, treated with a volatile solvent for the
a flexible composition, and' may at any time resin, such as methyl
ethyl ketone, toluene, or thereafter be treated with' a solvent for
the mixtures of these materials' with diluents, resin causing the dry
flexible 'material to applied to the base which is to be stiffened,
become stiffened and the solvent is allowed to evaporate, thus'120
There are several embodiments of this in producing a stiffened sheet
material.
vention, all of which produice the same dry, The following examples
are given to illusflexible impregnated sheet material ' In one trate
various embodiments of this invention.
method, the fibrous sheet material is first im Parts and percentages
are by weight unless pregnated with the above-described resin latex,
otherwise specified ' 125 stripped to remove excess liquid, and then
EXAMPLE 1 An impregnating medium impregnated withy an aqueous
coagulant' was prepared by blending 3 parts of an aqueous solution,
followed bydrying In a second pro latex containing 50 % solids in the
form of cedure, the fibrous sheet material is first -p'Olystyrene and
1 part of an aqueous latex conimpregnated with an aqueous coagulant
solu taining 45 % solids in the form of an 80/20 130 slightly stiffer
and harder compositions as the butadiene proportion is reduced and
softer more elastic compositions as-the:butadiene,proportign
is;,inereased:, -,The,:samervariety of ?compositions can be obtained
by mixing well 70 known plasticizers with; for example; polystyrene,,
a polymerised vinyl or vinylidene halide or polymerised acrylates The
latex used as starting material in the preparation of the impregnating
bath of this 75 invention is a, colloidal dispersion of one or more of
the above resins in an 'aqueous medium.
Preferably, the dispersion contains from 40 % to 60 % resin solids,
while the remainder is substantially all: water These dispersions or
80 latices are available commercially on the open market in:
concentrations of 40 % to 60 % solids, or they may be prepared by
knowi methods, such as dispersion polymerization.
The latei of resin and water constitutes the 85.
largest portion' 6 f the impregnating mixture of this invention
-'and,,-the -additives described below constitute less than 15 %, of
the total weight of the impregnating mixture, although there are some
embodinfents of ibis invention 90 wherein a large amount of filler is
employed, After all additives are incorporated into the latex, it may
then be diluted if desired, and in any case will contain 20 % to 60 %

7. resin solids in the final form as -an impregnating bath 95 Anionic
surface-active -',wetting agents are required additives to the latex
utilized in this invention The wetting agent is' required to cause the
fabric-tobe easily wetted byythe latex and thus permit the
interstices-of the" support'100 ing fibrous materials to fill quickly
and completely with the impregniating latex(' The more commonly known
of, such compounds are the alkali metal organic sulfates, sulfonates,
phosphonates, and phosphates,, in which the organic 105.
group is a long chain alkyl -or alkyl aryl group.
Included among these compounds are isopropyl naphthalene sodium
sulfonate, 'the -dioctyl ester of sodium, sulfosuccinic acid, sodium
alkyl sulfates, sodium -alkyl phosphates, sodium alkyl 110 o
phosphonates, the sodium salt of 2-ethylhexyl.
polyphosphate, ammonium soaps, and other commonly'known -;anonicg
detergents.
The preferred amount of the surface-active wetting agent may vary from
0 5 % to 5 % by 115 weight of the resin solids present When the solids
content of-the latex is 20 % to 60 % the amount of the surface-active
wetting agent becomes 0 1 % to 3 0 % by weight of the total latex
Larger amounts than 3-% are not harm 120 ful to the process and the
limit of 3 % is selected for economic reasons entirely Less than 010 %
of wetting agent reduces the speed with which -the, sheet material may
be impregnated and thereby' the efficiency of the-125 process, if time
is-a factor in the process Coagulants which,may" be employed in the
process' of this invention are the water-soluble polyvalent metal
salts such as chlorides, nitrates, sulfates and, acetates-of, for
example; 130 copolymer of styrene/butadiene 'To this latexblend, there
was added 0 5 %: by weight -of resin solids of an organic phosphate
surfaceact Ove agent salt under,the namen Victor ' Stabilizer" sold,
by the, 'Victor 'Chemical' Works (Chicago, Ill) A piece of cotton
flannel weighing 0 36 pounds per square yard was dipped into, a 1 %
aqueous solution of aluminium sulfate, stripped of excess liquid by
passing the wet fabric between rolls spaced:
033 " aparti and thereafter the fabric was dried at 100 C in an air
oven The dried fabric was then dipped into-the above' described
latexblend and passed between stripping rolls spaced 033 ': apart The
impregnated fabric' was placed horizontally in an air oven maintained
at 100 C and dried in that position, The' amount of resin solids in
the dried impregnated fabric amounted to 69,% of the total weight of
the impregnated fabric A portion of' this-impregnated fabric was
tested tot determine its.
ability to absorb a solve nt,for the resin The solvent utilized was a
mixture of' 90 % by weight of toluene and 10 % by weight of a
commercial petroleum naphtha fraction boiling "in'the range 6 ff 100

8. "'t 167 C The-material was sufficiently absorbent that 71 7 % -of the
dry weight of the fabric was solvent Upon evaporation of the solvent
material the fabric -30 is a stiff, boardy, material which is very
tough and flexes with difficulty.
As the major ingredient of the impregnating latex there may be
employed, for example;polystyrene, polymethylstyrene, polyvinyl
halides, polyvinylidene halides, polyacfylates, polyacrylonitrile, and
polyalkylacrylates Copolymers of styrene/butadiene, high in styrene
content and low in butadiene content are also operable It is desirable
in many instances to employ a plasticized resin, such as a mixture of
polystyrene and a copolymer of high styrene content and low butadiene
content, the copolymer acting as a plasticizer and thereby causing the
polystyrene to be less brittle although retaining its stiffness Other
knowi' plasticizers such as organic esters, may be in, corporated with
the base resin to reduce brittleness in the same manier as the
styrene/' butadiene copolymer is used above Polymers of styrene or of
vinyl halides are particularly desirable because of their availability
and low cost Many varieties of resins and combinations of polymers
have been found to be -useful in this process One useful group of
resins is a copolymer of styrene/butadiene containing 4 % to 20 % by
weight of butadiene A press ferred formulation-is a mixture of 3 parts
polystyrene with 1 part of an 80/20 copolymer of styrene/butadiene,
which mixture has a total composition of 95 %' styrene and 5 %.
butadiene The proportions of polystyrene and the-styrene/butadiene
copolymer cain be varied within the general range of 4-20 % by weight
65, of butadiene' in the total mixture' to, produce 785 058 ' 3.
aluminium, magnesium,;calcium, iron, tin, copper, cobalt, chromium, ?:
cadmium;and strontium Of' these various salts: calcium chloride,
ferric sulfate 1 magnesium sulfate, and aluminium sulfate
are-desirable, althotlgh the latter two are preferred because of their
lower costs, better solubility characteristics, and the fact that they
do not impart undesirable-color to the finished product The alums,
such as:the i O ' potassium, 'sodium, or' ammonium aluminium sulfates
are as desirable as aluminium sulfate as the coagulant in this process
The 'amount of coagulant required will vary slightly with the chemical
nature of the i-5 coagulant salt, the type and amount of resin
employed, and' other reaction conditions For the preferred coagulant,
aluminium sulfate, used with a latei of styrene/butadiene resin
approximately 0 5 %' by weight of the resin solids present in the
latex is sufficient 'to accomplish the desired result When used with
other resin formulations, 'the amount of aluminium sulfate may vary
from 0 5 % to 3 0 % by weight of-the resin solids For other
coagulants, some of which-are known to be less active and less
efficient than aluminium 'sulfate, the amount employed may be as' high

9. as 10 % or 1-5 % by weight of the resin Solids:.
In one embodimnent of this invention, the resin latex is creamed by
partially coagulating the latex solids, and theresulting creamed latex
is utilized as the impregnating medium.
Creaming of the' resinous latex-is accomplished by the well'known and
simple procedure of ' adding small quantities of a coagulant tio the
latex while the latex is being agitated As mote and more coagulant is
added the latex-becomes creamy in appearance and in consistency, due
to the formation of small agglomerates from 402 the original latex
containing colloidal particles.
The addition -of more coagulant will cause the formation of large
lumps of resin which separate easily from the aqueous medium and this
should be avoided Visual observation may be employed to control the'
amount of coagulant required to reach a creamy consistency in the
latex In general the amount of coagulant required is 0 25 % by weight
of the resin solids in the latex.
As a final: step in the preparation of the impregnating latex, water
may be added to form the desired concentration of resin solids, which
for most embodiments of this -invention will be from 20 % to 60 % by
weight of solids.
For the preparation: of shoe stiffeners, a concentration of 40 %
solids has been found to be preferable The material which is to be
'stiffened may, in general, be any fibrous sheet material such as
fabric, textiles, felted materials, mats or paper.
The sheet material may be made of natural or synthetic fibres ora
mixture of the two; In the case of shoe stiffeners-the material
commonly employed is a cotton flannel, although nonwoven fibrous sheet
material or even paper may be used in some cases Filler-materials may
be incorporated info the impregnating medium of this invention: to
serve several useful purposes,:For example, the filler mniay be'used
to reduce the'cost'of the materials 70used in-the impregnating bath
The useiof T' filler in many instances causes the impregnated material
to be -more porous and therefore to be able'to absorb more solvent
and:achieve a greater stiffness In some cases, the use of a 75 filler
enhances the adhesiveness of the impregnated material to an adjacent
laminating layer In the manufacture of shoe parts using the
impregnated shoe stiffener of this invention it has been found that
the incorporation 80 of filler material permits the' shoe stiffener to
be handled easily when it is wet'with solvent and ready-to be
incorporated into the shoe part and, futhermore, 'after the shoe part
has been assembled 'theeic is less likelihood that -resin 85 solids
will migrate from the shoe stiffener and cause visible spotting on the
leather surfaces of the shoes Filler materials which may be used
include water-insoluble fillers such as siliceous materials,

10. infusorial earths, bentonite clays, 90 and "Dicalite " (Registered
Trade Mark).
The'amount of Sfiller mnaterial which may be used may' be as much'as
100 % by weight of the'resin solids present and a range of values of
20 % to 50 % is preferable for most em 95 bodiments of this inventiori
' Thickeners have utility in this inyention when it is desired to
impregnate a fabric with greater and greater amounts of resin solids,
and when fillers and other ingredients of the 100 latex have a
tendency to settle out -Thickeners which have 'been -used successfully
include methyl cellulose and methyl carboxy cellulose.
In the process of preparing a stiffened material such as a shoe
stiffener, cotton flannel 105 or other supporting sheet material is
-dipped, sprayed or covered with the impregnating latex, which is
prepared according to the above description.
The excess liquid is removed from'the wet 110 impregnated material by
a suitable means such as coacting stripping rolls, or a wiper knife.
Such an operation is capable of -loading the supporting material to
the desired amount of % -or more by weight of impregnating I 15 solids
if the original impregnating latex contains 40 % solids The stripped
impregnated material is then contacted with an aqueous solution of a
coagulant salt such as-aluminium sulfate or alum and finally dried-at
100 ' C or 120 greater to evaporate-the remaining water from the
impregnated material In the previous description it has already been
shown that the fabric may be treated with the coagulant prior to the
step of impregnating with the latex or 125 the fabric may be treated
with coagulant subsequent to the latex impregnation and it is not
intended that this invention be limited to any patiualar order of
procedure so long as there are two steps-involved in this process;
namely 130 78.5058.
with each of the following two liquid baths in 45 any order of
treatment: ( 1) an aqueous latex containing 20 % to 60 % by weight of
dispersed vinyl resin solids and at least 0 10 % by weight of an
anionic surface-active wetting agent and ( 2) an aqueous solution of a
poly 50 valent metal salt; drying the thus impregnated sheet material
and recovering a dry, flexible, impregnated sheet material capable of
being stiffened by the action of a solvent for said resin 55 2 A
process according to claim 1 in which said vinyl resin is a mixture of
polymeric styrene and polymeric butadiene, the mixture containing 4 %
to 20 % by weight of butadiene.
3 A process according to claim 1 or claim 2 60 in which said
polyvalent metal salt is aluminium sulfate.
4 A process for preparing shoe stiffeners comprising dipping a cotton
flannel fabric into an aqueous latex containing ( 1) 20 % to 60 % 65
by weight of resin solids comprising 75 % of polystyrene and 25 % of

11. an 80/20 copolymer of styrene and butadiene and ( 2) 0 10 % to, 30.0 %
by weight of ani inionic surface-active organic compound from the
group consisting of 70 alkali metal alkyl and alkali metal alkyl
arylsulfates, sulfonates, -phosphates, and -phosphonates; dipping the
latex impregnated flannel into an aqueous solution of aluminium
sulfate, and thereafter drying the twice-dipped 75 flannel and
recovering a dry, flexible shoe stiffener.
The process for preparing sheet material capable of being stiffened
substantially as herein described 80 6 The process for preparing shoe
stiffeners substantially as herein described.
( 1) an impregnation of the, fabric with a resin latex and ( 2) an
impregnation of the fabric with an aqueous solution of a coagulant
salt.
After the second impregnation step in any of the above process
alternatives, the impregnated material contains small agglomerates of
resin particles uniformly dispersed throughout the sheet material
After drying to remove the remaining water, this material may be
stored if desired, or it may be used in the production of a stiffened
article of manufacture, such as a box toe or counter in a shoe, a
laminate with other materials 'and shaped molds The stiffening process
is accomplished by treating the dry, impregnated material with a
solvent for the resin, forming the solventtreated material into the
desired shape and allowing the solvent to evaporate leaving a stiff,
self-supporting, article The solvent for the polystyrene resin may be
methyl ethyl ketone, toluene, or mixtures of these materials, and the
solvent for the polyvinyl chloride resin may be methyl ethyl ketone,
cyclohexanone, or mixtures of these materials with each other or with
diluents.
The process of this invention is particularly useful in the
preparation of shoe stiffening materials such as box toe or shoe
counters and it also finds a wide variety of uses in the preparation
of impregnated materials which areused to stiffen or otherwise
strengthen material with which it is laminated The impregnated
material of this invention may be used to repair sheet metal articles
such as roof gutters, downspouts, fenders and bodies of automobiles.
This material also finds use in covering the decks and hulls of small
boats, in the preparation of artificial limbs, in the manufacture of
puppets and display devices and in a variety of laminating
applications.
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* GB785059 (A)
Description: GB785059 (A) ? 1957-10-23
Improvements relating to vinyl resin based sheet materials for use, for
example, as acovering material for floors and like surfaces
Description of GB785059 (A)
A high quality text as facsimile in your desired language may be available
amongst the following family members:
DE1059175 (B) FR1134353 (A)
DE1059175 (B) FR1134353 (A) less
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PATENT SPEC IFICATINI N
' l, , , , l, '', PTNP I l A t N: - , " Of:' ' d _ E'"785059 e -Date
of Application-andfi'irig>omple e Speif aeion: March 30, 1955.
S t iNo9300155, l' '' - '.
l B y Aplication nalein Italy on April 281 I ':.
Comete Specification Published: Oct 23, 1957 ' ,: ' Index at
Acceptance:-Class 140, A( 2 N 3 5 G 9 10 B 3 '.
International Classification:-D 06 k ' ' -" ' , 'COMPLETE
SPECIFICATION ' ' '
Improvements relatingto Vinyl Resin Based Sheet Materials for'Use, for
example, as as'Covering Matierial for Floors and Like Surfaces ' ' We,
SOCIETA DEL LIN Ot EUM SOCIETA PER -in the linear dimensions of the

13. material in'onie 45 AZ Io NI, a ' Limited Liability' -Company or -more
directions '"The reason why pressure, organised under the laws of
Italy, of 28 Via 'for example in these forms,, produces relaxation
Macedonio Melloni, Milan, Italy, do hereby 'of the material is that,
in contrast to vulcanised declare the invention, for which we pray'
that rubber, which is inherently-elastic and capable a patent may be
granted to us, and the method therefore of fully'returning to initial
dimei S 50 bvwhich it is to be performed, to be particu sions when the
stresses producing deformation larly described in' and by 'the
'following have been removed; a plastified vinyl' resin statement: -'
mass, being a thermoplastic material, deforms ' This invention relates
to vinyl resin based permanently, or' substantially 'so, under the
sheet materials -for use,for example, as a applied stresses ' ' 55
covering material for fioors and like surfaces: The two opposing
effects, of shrinkage and Such materials usually c ontain a
substantial 'relaxation, generally occur 'in respectively proportion
of a suitable plastifier, and it is different degrees-'in ha
'dimensional' ense, known that they tend to 'be disadvantageous
depending inter alia on the position and by reason of their tendency
to shrink' and also service conditions of the material Obviously, 60
to expand, the shrinkage and'-expansion, the in such a case only the
net (resultant) effect latter being-usually referred to as
"relaxation," of the two processes may be observed frequently
occurring simultaneously and of It is':kno Wn, with a view to
minimising the course in opposition to-one another in-'one and two
effects of shrinkage and relaxation, to the same sheet of vinyl resin
kbased material incorporate a afiller with the vinyl resin, the '65
Shrinkage is due to the effect-upon the effect of the filler in
the'composition being to molecular structure of the vinyl resin of the
reduce the percentage of vinyl resin therein presence in the
composition of the plastifying -and proportionately the degree to
which the agent Thus the plastifying agent, which processes of
shrinkage and relaxation can usually requires to be present in
substantial 'occur therein under any given conditions of '70
v:proportion,-causes a gelling or swelling of the service.
vinyl resin component-of the composition with The presence of a filler
in the vinyl resin resulting creep or spacing apart of the 'material
produces however 'a marked molecules thereof and in course' of time
this 'degradation of the material as regards certain creep or spacing
apart 'of the molecules useful properties thereof, including
resilience 75 may be reduced with resulting shrinkage of the -and
resistance to wear and scratching, which material' either owing to
loss: of' plastifying have to-be present-in high degree in a, material
agent from the composition, e g through suitable for use as a floor

14. covering.
evaporation, or through the effect of "thermo The present invention
has had for its objet elasticity," by which is meant the elastic to
provide an improvement' which will confer 80 recovery of a
deformation,, such'recovery being upon a vinyl resin based sheet
material such -confined by the limit of molecular creep, which
structural characteristics as will prevent the is reduced as
temperature rises ' appearance in the material of either shrinkage
Relaxation: is -produced by the weight of or relaxation under any
normal conditions of persons continually treading upon the material,
service of the material and this,' without the '85 i.e In the case of
a floor covering, and also 'necessary use of a filler for this purpose
and by the weight of objects continually resting without impairing in
any way or degree the -upon it and it generally results in an increase
-peculiar features of vinyl-resins, in-particular lPrice 14 S 6 d:
Price 4 A M.
2 ' f " 78 Q 59- 75:
their marked resiliency and resistance to wear-ing and scratching.
Akcc 6 ording to the invention, there is provided a laminated material
for floor covering and like purposes comprising at least two laminae
composed of a highly plasticised, highly resilient, wear and scratch
resistant polyvinyl resin devoid or substantially devoid of filler
material, and at least one other lamina composed of a vinyl resin
which in lamina form is substantially non-deformable in' the plane of
the lamina, this second mentioned lamina, or in a case where there are
two or more, said second mentioned laminae, constituting a reinforcing
element in the material effective to stabilize the first mentioned
laminae and therewith the materia as a' whol againist j 6th hrinkage
and relaxation, the -componeiint 'laiinae' of the imaterial being
firmly bonded to one another therein and the resilient -laminae, or in
a case where, there are more than two resilient laminae, two of the
resilient laminae, forming respectively tle outer laminae of the
material, one-of them carrying the w earing surface thereof For
convenience in-the further description of -the invention and i
the,appended claims the-laminae of plastified yinyl resin in the 39
laminated material will be referred to as the "resilient laminae "and
-the other lamina or laminae will be referred to as the "nondeformable
lamina, (or laminae)' " The arrangement -of the laminae in the
laminated material may vary, for example to suit the particular
service requirements of the material Owing,'to the absence or
substantial absece of a filler ingredient in the resilient :40
laninae, a-material is-provided which is particularly suitable to
withstand the -stresses which are produced in it under the conditions
of use of the material, and inwhich moreover thl remarkable resilience

15. characteristic of C 45 vinyl resins is enhanced as compared with the
use as heretofore of a filler ingredient in the resin material In a
case where there are more than three lminae in the material, the -two
types of 5.0 laminae (resilient and, non-deformable), as regards at
least the majority of the laminae of the -material, may be arranged in
alternate sequence as regards the order in which - they are
superposed: upon one -another in the material -Alternatively, in a
case where there are five, or an unevennumber more than five, laminae
in the material, the two types -of laminae may be so arranged-that
each nondeformable lamina is sandwiched between two -60 resilient
laminae' There may:be-in the material two or more resilient ': liminae
arranged in immediate success ion, i e unsepar ted from_ one another
by an intervening nonii-deformable lamina, the arrangement generally
being one in which, as in an embodiment of the invention hereinafter
described, the lamina carrying thewearing surface of the material is
one of suh two or nmore resilient lamina? rranged irishnid ate
succession 70 The non-deforniabl: laminaiar laminae may conveniently
be composed of'-fpire viiyl:esin, X by 'Which is meant vinyl resin dev
soiinof-a content of either a plastifier 6 rsa- filler;'qr it may be
composed of a vinyl Resin _which-con '75 tains a small proportion of
aplast 'fier or a small proportion of a suitable filler.
: Thi manufacture and general -structuire of.
the laminated material of this invention will now be described in
greater detail with refer 80 ence to an embodiment of the invention,
it being understood that in the preparation of the'individual'lamiriae
and-the'assdmbling and bonding' of the 'se iminam'tog'ether
conventional technique in the art of manufacture of 85 vinyl resin
floor covering materials is followed.
The mixing of the vinyl resin with the other ingredients to form the
respective laminaforming compositions:is carried out in any suitable
mixer, e g a Banbury-mixer 90 By way of example, the two compositions
-may have respectively the following percentage (by weight)
compositions:
Non-deformable lamina-forming composition:
Polyvinyl chloride 90 95 Plastifying Agent 9 Stabilising Agent
(Filler) 1 Resilient lamina-forming composition:
Polyvinyl chloride 65 -Plastifying Agent Z5 100 Stabilising Agent
(Filler) 3 Colouring matter including pigmnents -7Suitable plastifying
agents include, fotinstance, the-dioctylphthalate and polyesters 105
of the " Paraplex" (Registered Trade Mark) type produced by Roehm &
Hass of Philadelphia Suitable stabilising agents (filers) include, for
instance, the basic lead silicate and 110 sulphates and the calcium
and cadmium stearates.
-After being processed under -heat qo a cylinder rolling mill of the

16. open-roll type,: the resulting composition, in a heated condition, 115
is caldndered in preparation for milling into larnminae having a
thigkness of 0 5 to 0 6 mm and a length and width conforming with the
dimensions required for the final {larninated) product 120 -In order
to ensure a perfect bond between the non-deformable laminae and the
resilient laminae, in spite of the marked difference between the two
types of laminae as regards elongation characteristics, the surfaces
of the 125 non-deformable laminae are:preferably treated -with a
-solution of a vinyl polymer or co-polymer n a suitable solvent, e g
cyclohexanone or chlorobenzene.
The laminae to form the laminated product 130 material being firmly
bonded to one another therein and the resilient laminae, or in a case
where there are more than two' resilient laminae, two of the resilient
laminae, forming 50 respectively the outer laminae of the material,
one of them carrying the wearing surface thereof.
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* GB785060 (A)
Description: GB785060 (A) ? 1957-10-23
Process for obtaining bleached semi-chemical pulp
Description of GB785060 (A)
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amongst the following family members:
BE536814 (A) CH332820 (A) DE1034473 (B) FR1129498 (A)
BE536814 (A) CH332820 (A) DE1034473 (B) FR1129498 (A) less
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The EPO does not accept any responsibility for the accuracy of data
and information originating from other authorities than the EPO; in
particular, the EPO does not guarantee that they are complete,
up-to-date or fit for specific purposes.
PATENT SPECIFICATION
A 785 11 tl 7 vv v
Date of Application:ond filing Complete Specification: April I, 1955.
No 9496/,55 Application made in Germany on April 8, 1954.
Complete Specification Published: Oct 23, 1957 y: ' ' Index at
Acceptance:-Class 2 ( 2), W 2, W 3 A( 2 A 2 B 4 C 8: 10 12 B).
International Classification:-D 21 c COMPLETE SPECIFICATION
Process for Obtaining Bleached Semi-Chemical Pulp We, ZELLSTOFFFABRIK
WALDHOF, a German Body Corporate, of 156, Sandhoferstiasse,
Mannheim-Waldhof, Germany, 'do hereby declare the invention, for which
we pray that a patent may be granted to us, and the method by which it
is to be performed, to be particularly described in and by the
following statement:, The object of the invention is a process for
obtaining bleached semi-chemical pulp from cellulose-containing raw
material, such as wood, and annual plants.
For some time, products which can be included under the term
"semi-chemical pulp," have been known in the art They are identified
by the feature that the cellulose-containing raw 'materials are first
only partially disintegrated 'by chemical means and the pulping of the
intermediate-product so obtained is completed by mechanical means The
semichemical pulp obtained is regarded technicallyin respect of the
process as somewhere in the middle between ordinary chemical pulp
which is completely disintegrated by chemical means and mechanical
wood pulp In the production of semi-chemical pulp the partial chemical
disintegration is pursued only until the lignin of the centre lamella
of the raw material becomes.
soft and is only partly dissolved out without, however, a complete
dissolving out of the lignin occurring -and without, in particular,
large quantities of carbohydrates being removed By this means much
higher yields are obtained than with the normal disintegration of
chemical pulp As compared with mechanical wood pulp the advantages are
obtained that, in the first place, less energy is required for
pulping, during which process, moreover, less damage is done to the
individual fibres and, owing to the fact that a portion of the lignin
is dissolved out, a purer product is also obtained which, however,
naturally contains much larger quantities of non-cellulosic substances
than ordinary chemical pulp which is fully disintegrated chemically.

18. In contrast to mechanical wood pulp, it is possible in the case of
semi-chemical pulp, to use the product for -high' grade purposes, for
example, for the manufacture of quality papers.
In such cases a special problem is caused by 50 the bleaching of the
product; owing to the numerous substances accompanying the cellulose;
for, on the one hand, a high degree of whiteness and purity is
demanded"for many purposes of use, and on the other hand; the 55
essential advantage of the semi-chemical process over the completely
chemical disintegra tion, namely, the much greater yield, should not
be lost by removing an excess of accompanying materials ' It is
therefore not imme 60 diately possible to transfer the processes which
are known and usual for bleaching ordinary chemical pulp, to the
bleaching of semi-chemical pulp Since with ordinary chemical pulp the
object is always to remove as much of the 65 impurities contained
therein as is required by the intended purpose of use of the product,
and in practice the only possible reduction of the yield is' that:
resulting from the removal of these impurities, the choice of the
bleaching 70 process depends in general only on the cost involved In
the bleaching of semi-chemical pulp, on the other hand, consideration
-must be given not only to the risk of an undesirable reduction in
yield but also to the chemical 75 nature and the physical structure of
the intermediate product, which,-being only 'incompletely
disintegrated chemically, can be largely influenced by the chemical
bleaching process, By the partial chemical disintegration process, 80
in contrast to the complete chemical pulp disintegration process in
which the individual fibres are chemically exposed, the fibre unions
are here substantially maintained and are only loosened or
pre-softened From all this it 85 appears that many points of view must
'be considered in the bleaching of semi-chemical pulp which make
necessary a special choice of the bleaching process to be used and, in
certain cases, a special arrangement thereof 90 ( _:-, -_:; 1:
; ' ' -785,060 Numerous processes for obtaining bleached
ge'i-chemidal' pulp have already been proposed All these processes,
however, have many important imperfections These originate partly in
the disintegration process and partly in the bleaching Whilst no great
care is needed for the complete chemical disintegration process and
the process may be carried out vigorously, in the case of the
semi-chemical disintegration of the semi-chemical pulp process, on the
other hand, it is necessary to proceed very carefully and with
accurate control of the conditions, so that, on the one hand,
excessive disintegration with a reduction of the yield and strength of
the product does not occur, while on the other hand, the presoftening
of the fibre ufion-is sufficient During the subsequent mechanical
finishing it must be ensured that the most complete distribution of

19. the material into the fibres occurs without thelatter being
excessively damaged; at the same time, however, care must be taken to
avoid unnecessary consumption of power These various conditions which
should be observed make it difficult to obtain a really perfect
product On the other hand, with the previously known methods, if a
good yield was obtained, a semi-chemical pulp was always produced
which still contained more or less undefibred bunches of fibres which
give rise to trouble during the subsequent processing and can only be
incompletely bleached and with difficulty and, therefore, have a
disturbing effect on the cleanliness of the product.
The processes proposed and normal hitherto for the bleaching of
semi-chemical pulp showed considerable imperfections In the majority
of cases the processes used previously -for the bleaching of normal
chemical pulp were simply applied to the bleaching of semi-chemical
pulp with very few or no variations at all However, from-the above it
is already apparent that such simple transferences could scarcely lead
to success In particular, the non-uniform nature of the product, that
is to say, the bunches of fibre still contained therein, made really
good bleaching difficult or even impossible In addition a uniform
chemical decomposition of wood is not-possible in practice, as is
known Whilst it is comparatively easily possible to remove the
imperfectly disintegrated portions by sorting in the case of normal
chemical pulp, this is not possible with semi-chemical pulp If,
however, a sufficiently and uniformly bleached semi-chemical pulp was
required, then it was hitherto necessary, owing to the resistance
which the incompletely disintegrated wood portions offered to the
bleaching,:to bleach much more intensively than normal, and this led
to an undesirably high expenditure in bleaching agents and also damage
to the fibre.
It has now been found that it is possible to obtain bleached
semi-chemical pulp from cellulose-containing raw material, such as
wood, annual plants'and the like in a simple and effective manner if
the raw material is first subjected to a partial chemical
disintegration then bleached, and finally mechanicallydefibrated
Surprisingly it became apparent that, by operating in this manner, it
was also 70 possible to influence the bunches of fibre insufficiently
affected by the chemical partial disintegration with a favourable
chemical effect during the subsequent bleaching, so that with the
mechanical finishing effected during the 75 last stage a practically
complete defibration may take place At the same time, the, bleaching
effect was also improved relative to the previously known processes
This was not to be expected, since in the hitherto-known processes 80
for the production of semi-chemical pulp it was precisely the
still-coherent bundles of fibre and incompletely-disintegrated wood

20. portions which had given rise to the greatest difficulties -in the
bleaching treatment By the 85 invention it is therefore possible, both
to improve the semi-chemical pulp disintegration and so to obtain a
uniform and valuable product simultaneously with simple means and
without additional operations, and also to 90 increase the bleaching
effect so that a further improvement in the product is obtained.
The partial chemical disintegration may be effected according to the
invention by various known processes In a further development of 95
the invention it has proved to be particularly favourable to carry out
the process with an acid sulphite solution For, apart from the
advantages of the process which the sulphite disintegration has, for
example, relative to the soda 100 or sulphate process, a product is
obtained therewith which, in particular, makes possible the effect
achieved by the invention in a particularly favourable manner.
The bleaching following the chemical partial 105 disintegration may be
carried out in various ways It is usually sufficient to use only one
bleaching stage; however, multi-stage bleaching is obviously also
possible All the known agents may be used as bleaching chemicals, 110
such as chlorine bleaching agents and per-compounds such as peroxides,
per-acids and their salts The bleaching may be effected, according to
the bleaching agents used, in acid, neutral or alkaline medium As an
extension 115 of the invention it has proved to be of special
advantage to carry out the final bleaching in alkaline medium When
using a multi-stage bleaching it is therefore sufficient for the last
stage to be effected in alkaline medium If 120bleaching is effected
only in one stage, it is, of course, of special advantage to provide
an alkaline bleaching in this stage It is preferable for the bleaching
to be carried out with a high pulp consistency 125 It has proved to be
expedient in many cases to carry out a mechanical preliminary
defibration already between the chemical partial disintegration and
the bleaching This mainly depends on the type of raw material used, on
130 'C 5 about 30 % of the added' quantity of wood being 'dissolved
out The product obtained is washed in water and the excess water is
removed The chippings now have a dry content of about 25-30 % They are
70 coarsely defibrated in a toothed disc mill adapted to coarse
grinding in such manner that more than half the material is obtained
in the form'of bunches of fibre Simultaneously with the'defibration or
directly thereafter, the mass 75 is intimately-mixed' with such a
quantity of a solutioni containing 5-7 % each 'of sodium peroxide and
sodium silicate that 4 5 % sodium peroxide and 5 %/ sodium silicate
are used on bonfie-dry fibrous substance After the mixing 80 the
fibrous material is yielded with a pulp consistency of about 22-25 %
(The term "pulp consistency ' defines the concentration of cellulose
in water expressed as a percentage by weight) It is stored with this

21. pulp consistency 85 at room temperature' until the bleaching agent is
substantially coinsumed; whereafter the fibre mass is separated
without'previous thinning into individual fibres' by means -of a
double pulveriser The fibre pulp yielded is further 90 worked up in
the usual manner after intermediate washing About 13 5 'tons of'the
above absolutely dry fibrous material are obtained.
If the product obtained in this manner is compared with such a product
in which the 95 division into individual'fibres is effected under
otherwise equivalelit conditions directly after the chemical partial
disintegration and is only then bleached, the-much-greater purity of
the -material produced according to ihe process of 100 the invention
is-striking The material is practically free of fragments and -bunches
of fibre and makes possible the formation of a homogeneous and uniform
sheet of excellent strength With the-same degree of beatinig a 105
continued tearing strength (i e the strength of a partly torn sheet on
further tearing from the initial tear-cald'ulated according to
'BrechtImset) of 120 was obtained for the product according to the
invention and Ai folding num 110 ber (i e the number of double folds
possible without breaking) of 1785, as compared with a continued
tearing strength of 68 and a folding number of 900 'in the case of the
product obtained according to the known 'process 115 Example 2 tons of
white barked birch wood are subjected in the form of chippings of
about 20 x x 5 mm'to a chemical partial disintegration with the use of
a bisulphite cooking liquor con 120 raining about-5 % sulphur-dioxide
and about' 1 % Ca O, with a ratio of cooking liquor to wood of 4 5:1
and a disintegration temperature of C, whilst the disintegration is
continued until about 20 %,6 f the quantity of added wood 125 is
dissolved out ' The product obtained is washed with W 5 ater' and -the
excess water is removed The chippings 'have, under these conditions, a
'dry content of about 30-35 %.
They are coarsely defibrated in an intermediate 130 its degree of
disintegration before boiling and on'the nature of the chemical
partial disintegration Whilst a mechanical preliminary defibration is
generally not necessary, -for example, when processing annual plants,
such pro' limin'ary defibration may be applied in the processing of
wood if a semi-chemical pulp is to be obtained with a particularly
high yield, that is to say, with a particularly mild chemical
pre-disintegration; nevertheless, the degree bof comminution should
not be taken too far before the boiling ' ' The preliminary
defibration, the bleaching and 'the final splitting-up into separate
fibres' may be' effected with any desired pulp consistency: IR has
proved to be particularly suitable to work' with the highest possible
pulp consistency Subsequent to the bleaching it is in many cases
unnecessary to effect washing out or thinning The process according to

22. the invention may be carried out under greatly varying conditions,
according-to 'the raw material to be processed, the product desired
and the other requirements resulting' from the existing situation '
The' optimum conditions should be ascertained from case to case
according to given stipulations It was, however, found that the
following method of operation is particularly'preferable and therefore
fulfils most of the conditions in a favourable manner The raw material
is first subjected to chemical partial disintegration which is taken
only far enough for a ' part of the substances causing the mechanical
cohesion of the -plant cells, such as the lignin, hemicellulose and
pectine, to be dissolved out The intermediate product thus obtained is
then first subjected to preliminary defibration under such conditions
that a fibre pulp containing a preponderant amount of fibre bunches-is
obtained This fibre pulp is then freed of a portion -of the fluid, if
necessary after a washing, then mixed with 'any chemicals required, in
the case of a peroxide bleaching, for example; with up to 10 %,
preferably 2-4 %, dissolved silicate 'calculated on absolutely dry
fibrous material, as well as with up to 2 5, preferably 0 125-2 5,
gramme-equivalents per kilogram of absolutely dry fibrous material of
a bleaching agent active in alkaline medium, such as hydrogen
peroxide, sodium peroxide, hypochlorite, and salts of per-acids 5
preferably in the presence of 0 5% alkaline hydroxide calculated
on-absolutely dry fibrous material, and afrer-sufficient.
reaction with oxidizing agent, mechanically divided, in a pulping
apparatus, for example, a disc mill, conical pulping mill or an edge
mill.
Example 1 tons of white barked birch-wood are'subjected in the form of
chippings of about 20 xx 5 mm to a chemical partial disintegration'
with 'the use of a bisulphite cooking liquor with about 5 %- sulphur
dioxide and about-1 ':/YTO,' using a ratio of cooking liquor 'to 'wood
of.
' 4 5 1 and a disintegration temperature of 785,060, 4 78506 disc mill
-adjusted to coarse grinding so that the major part of the material is
obtained in the form-of bunches of fibre Shortly before, during or
directly after this pulping operation the material is' intimately
mixed with such a quantity of a solution containing 5 = 7 % each of
sodium peroxide and sodium silicate-that about 2 %, sodium
peroxide:and: about 5 % sodium -silicate are used on bone dry fibre
substance Subsequently, the fibre material is stored at room
temperature for 10 hours and then split up into separate fibres by
means of a double disc mill without previous thinning; or washing The
fibre pulp obtained is washed in the usual manner and further
worked-up, About 15 tons of a practically splinter-free product of a
bright colour is obtained.

23. Example 3:
tons of white-barked birch wood are subjected to a partial
disintegration and coarse preliminary defibration as described in
Example 1 The coarsely defibred material is next intimately mixed with
5 % sodium hypochlorite and 5 % Na OH, calculated on bone dry fibrous
material, in a solution containing 3 % each of the two substances and
stored for about 1 hour at room temperature Subsequently, intermediate
washing is effected in known manner After'the washing the fibre pulp
is brought to a pulp consistency of 30 %,by means of a revolving
filter and subsequently mixed in a double shaft mixer with 2 % Na 20
and 3 % sodium silicate in a 7 % solution of each substance After
storing for about 8-12 hours the fibrous material is split up
immediately into separate fibres by means of a double-disc mill and
subsequently washed in known manner A fibre pulp of a high degree of
purity and good whiteness is obtained.
Example 4 tons of white barked birch wood are subjected to a chemical
partial disintegration, a preliminary defibration and bleaching as
described in Example 1 Before splitting up into separate fibres a
known washing is effected removing the incrustations dissolved out
during the bleaching Subsequent to the washing'the fibrous material is
dehydrated by means of a revolving filter or worm press and split up
into ' separate fibres in a disc mill The fibre pulp thus obtained is
somewhat behind the products obtained according to Examples 1-3 in
respect of its purity, but is, after the splitting up into separate
fibres, practically free of the dissolved reaction products formed
during the bleaching, so that washing after splitting up into separate
fibres may be dispensed with.
Example 5 tons of white barked birch wood are subjected to chemical
partial disintegration, a preliminary defibration, bleaching and
washing as in Example 4 The fibre pulp thus obtained is then split up
into separate fibres with a pulp consistency of 2-10 % in a disc mill
or a conical staff engine The pulp obtained by this operation is not
so pure as that obtained in Examples 1-3; it contains instead a
considerably smaller proportion of splinters, fibre-bunches and the
like than a-fibre pulp which has beensplit up
under-otherwise'identical conditions directly 70 after the chemical
partial disintegration, that is to say; before the oxidizing
after-treatment.
Example 6 - 10 tons-of chopped wheat straw are subjected with the use
of a bisulphite cookingliquor con 75 taining about 3 % SO and about 0
8 % Na OH at a boiling temperature of 115 C and a ratio of cooking
acid to straw of 75:1, to a chemical partial disintegration, by which
about 35 % of the added, bone-dry above-mentioned quantity 80, of
straw is dissolved The material thus obtained is, after intermediate

24. washing, dehydrated on a revolving filter, whereby a dry content of
about 30 % is regulated Subsequently, the material is intimately mixed
with such an 85 amount of a solution containing 5-7 % each of sodium
peroxide and sodium silicate that about 4.5 % sodium peroxide and
about 5 % sodium silicate are used on dry fibre-pulp The material
obtained after about 10-20 hours storage is as 90 in Examples 1, 4 and
5 further treated and split up into separate fibres.
Example 7 tons of white barked birch wood are subjected in the form of
chippings of about 20 x 95 x 5 rmm to a chemical partial
disintegration with the use of a cooking liquor containing about 5 %
sodium sulphite (Na 2 SO,) and about 1 % sodium bicarbonate (Na HC Oo)
at a ratio of cooking liquor to wood of 4 5:1 and a dis 100
integration temperature of 175 C, the period of boiling being such
that about 25 % of the added quantity of wood is dissolved out The
product obtained is washed with water and the excess water is removed
The chippings now 105 have a dry content of about 25-30 % They are
coarsely defibrated in a toothed disc mill adjusted to coarse grinding
so that more than half the material is yielded in the form of fibre
bunches Simultaneously with the defibration 110 or immediately
thereafter, the mass is intimately mixed with such an amount of a
solution containing about 5-7 % each-of sodium peroxide and sodium
silicate that about 4 5 % sodium peroxide and about 5 % sodium
silicate 115 are used on bone dry fibre substance After mixing, the
fibre material is yielded with a pulp consistency of about 22-25 % It
is stored with this pulp consistency at room temperature until the
bleaching agent is substantially used up 120 Subsequently the fibre
mass is split up into separate fibres by means of a double disc mill,
without previous thinning The fibre pulp obtained is further worked-up
in the usual manner after intermediate washing About 13 5 125 tons of
absolutely dry fibre material are obtained.
If the product obtained in this manner is compared with a product in
which the splitting up into separate fibres is effected immediately
130 785,060 whereafter, if desired after washing, the fibre pul p is
freed from a part of the liquid associated therewith, treated with any
chemicals necessary for the bleaching, for example stabilisers and
bleaching agents, and, after the bleaching 45 agent used has acted
sufficiently, is mechanically defibrated.
7 A process as claimed in claim 6, in which the bleaching step is
carried out with a bleaching agent effective in alkaline medium, such
as 50 hydrogen peroxide, a hypochlorite or a salt of a per-acid.
8 A process as claimed in claim 7, in which the bleaching step
comprises treating the fibre pulp with up to 2 5, preferably 0 125-2 5
55 gramme-equivalents per kg of absolutely dry fibre pulp, of a
bleaching agent effective in alkaline medium, and preferably also 0

25. 5-10 % alkaline hydroxide, calculated on absolutely dry fibre pulp 60
9 A process as claimed in claim 8, in which the bleaching step
comprises treating the fibre pulp with a mixture comprising up to 10
%, preferably 24 %, dissolved silicate, calculated on absolutely dry
fibre pulp, and up to 2 5, 65 preferably 0 125-2 5 gramme-equivalents
per kg of absolutely dry fibre pulp, of a peroxide, and preferably
also 0 5-10 % alkaline hydroxide, calculated on absolutely dry fibre
pulp A process as claimed in any of claims 70 6-9, in which the
mechanical defibration is effected by means of a disc mill, a conical
pulping mill or an edge mill.
11 Processes for obtaining bleached semichemical pulp substantially as
hereinbefore 75 described with reference to the Examples.
W P THOMPSON & CO,, 12, Church Street, Liverpool 1.
Chartered Patent Agents.
after the chemical partial disintegration under conditions which are
otherwise the same, the much greater purity of the pulp produced
according to the process of the present invention is striking The pulp
is practically free from splinters and bunches of fibre and makes
possible the formation of a homogeneous and uniform sheet of excellent
strength properties.
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* GB785061 (A)
Description: GB785061 (A) ? 1957-10-23
Improvements in or relating to electro-luminescent elements
Description of GB785061 (A)
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26. The EPO does not accept any responsibility for the accuracy of data
and information originating from other authorities than the EPO; in
particular, the EPO does not guarantee that they are complete,
up-to-date or fit for specific purposes.
PATENT SPECIFICATION
7859061 Date of Application and filing Complete Specification April 4,
1955.
No 9764/55.
Application made in Netherlands on April 6,1954.
Complete Specification Published Oct 23, 1957.
Index at Acceptance:-Class 39 ( 1), 54 (A: C: D: F: J: K: Q: R), S( 6:
8).
International Classification: -C 09 k.
COMPLETE SPECIFICATION
Improvements in or relating to Electro-Luminescent Elements We,
PHILIPS ELECTRICAL INDUSTRIES nescence The invention has for its
principal LIMITED, of Spencer House, South Place, object to provide
improved electro-luminescent 50 Finsbury, London, E C 2, a British
Company,, elements comprising electro-luminescent do hereby declare
the invention, for which we materials which exhibit a strong
alternatingpray that a patent may be granted to us, and current
luminescence and, moreover, in many the method by which it is to be
performed, cases, direct-current luminescence.
to be particularly described in and by the fol According to the
invention an electro 55 lowing statement: luminescent element
comprises a layer of
This invention relates to electro-luminescent electro-luminescent
material sandwiched elements between two electrodes, at least one of
which It is known that certain materials emit radi electrodes is
transparent to light emitted by ation when exposed to an electric
field Until said material upon its excitation, is character 60
recently, such phenomena have been described ized in that the
electro-luminescent material principally with respect to those cases
where is manufactured by a method in which zinc the electric field was
an alternating field, but sulphide or z Inc cadmium sulphide is heated
recently it has been found that with certain in a sulphurizing
atmosphere at 700 C to materials luminescence occurs if they are 1200
C admixed with compounds of one or 65 exposed to a constant electric
field The two more of the alkali metals, which compounds phenomena
will hereinafter be referred to as produce sulphides in a sulphurizing
atmos"electro-luminescence " Where it is deskir phere, and with
activator compounds of one able to distinguish between the two, the

27. last or more of the elements manganese, copper mentioned phenomenon
will be referred to as and gold 70 "direct-current luminescence" and
the first By employing the above method to manumentioned as
"alternating-current lumines facture the electro-luminescent material
cence" The electro-luminescence may be grains are produced consisting
of zinc sulobserved, for example, if a layer of such a phide or zinc
cadmium sulphide, activated by substance is covered on either side
with an one or more of the elements manganese, 75 electrode and a
voltage applied between the copper and gold, which grains have a thin
surelectrodes at least one of the electrodes being face layer
consisting of sulphides, (which may pervious to the radiation produced
include poly-sulphides), of one or more of the A few satisfactory,
known electro-lumines alkali metals Although the phenomenon of cent
materials contain as a matrix zinc sul the electro-luminescence of the
compounds 80 phide or zinc cadmium sulphide and an activ produced in
this manner cannot completely be ator, for example manganese or copper
In accounted for, it is practically certain that it the methods of
producing these electro is related to the sulphide layer on the grain
luminescent materials measures different from surfaces If the
electro-luminescent material those taken in the case of the production
of a obtained is washed with water, so that the sul 85,
photo-luminescent material from the same phides are dissolved, it is
found that the matrix and the same activators must be material has
lost its electro-luminescent pro = employed In the literature a few
data are perties.
found on this subject, for example, concern From a large number of
experiments it has ing the use of zinc oxide or lead oxide, applied
been found that the copper, manganese or gold 90 to or in the grains
of the luminescent material, is absorbed into the interior of the
electrothe photo-luminescent material being ren luminescent grains and
that the sulphides of dered, it is said, electro-luminescent the
alkali metals are always found in a thin These known methods provide
materials surface layer.
which exhibit alternating-current lumines The above method may be
carried out in 95 cence, but substantially no direct-current lumi
various ways For example, first photolrprico t e, luminescent
zinc-sulphide or zinc cadmium the side facing the electro-luminescent
layer.
sulphide may-be produced by -heating, in-nor- To this -end use; may
for example be made mal manner,' zinc sulphide in a sulphurizing of
two glass plates, a surface of each of which atmosphere at 7000 C to
1200 C with activ is rendered conductive, for example by treatator
compounds of one or more of the elements -ing it with tin oxide These
surfaces thus 70 manganese, copper and gold and by-heating treated

28. with tin oxide are transparent to the the photo-luminescent'product
thus obtained:'emitted radiatioh If desired, one of the again in a
sulphurizing atmosphere at 700 C plates may of course be covered
simply by to 1200 C in the presence of compounds of adhering to it a
metal foil for example of aluone or more of the alkali metals,
-which-latter minium In order to -isolate the material 75 compounds
produce sulphides-in this silpliur completely from the surroundings,
the gap izing atmosphere However, as an alternat between the edges of
the joined-plates are ive the two measures according to this method
filled for example by paraffin wax or lacquer.
may be combined and as a further alternative In order that the
invention may be readily first z Inc sulphide-or zinc cadmium sulphide
-carried into effect, examples of methods of 80 may be-heated-under
the said conditions with manufacturing the electro-luminescent
matericompounds of one or more of the alkali metals, als will now be
described:-: after which the product obtained is activated by heating
it wjth compounds of one or more EXAMPLE I of the elements manganese,
copper and gold A mixture of The sulphurizing -atmosphere may, for 1
ginm mol of Zn S, 85 example, consist of hydrogen sulphide, carbon 0
05 gin tiol of Li CO, disulphide, or nitrogen charged with sulphur 0
01 gmn mol of Mn(NOQ), Suitable compounds of the alkali metals are is
produced and heated to 900 C in an IIH 25or example carbonates,
nitrates, oxides or: atmosphere for about one hour The sub_hydroxides
For the compounds of man stance obtained exhibits yellow electro-lumin
90 ganese, copper and gold use may be made of escence.
those compounds which are normally used fox In the aforesaid example
the lithium carproducing photo-luminescent sulphides, for bonate may
be replaced by the carbonate of example carbonates, nitrates or oxides
sodium, potassium, rubidium or caesium If .The luminescent compounds
or materials desired, carbonates of more than one of these 95 exhibit
an emission which is determined sub elements may be employed, the sum
being -' stantially only by the interior of the grains then 0 05 gin
molecule Instead of usingand not by_ the surface layer of the alkali
the H 2 S-atmosphere, use may be made of an metalf sulphide atm
Eosphere of C 52 vapour As a further The, copper and, gold content is
preferably alternative, the H 2 S may be charged with subl 100 chosen
between 3 10 and 5 10 a gram atom phur by passing HS gas over molten
sulphur.
per gram molecule of zinc sulphide or zinc If desired, nitrogen may be
passed over molten cadmium sulphide If manganese is used as sulphur
and the heating may be performed in an activators the manganese
content is prefer-, this nitrogen charged with sulphur.
ably chosen to be 10-3 to 8 10-2 gram atom of manganese, per
gram-molecule of zinc sul EXAMPLE II 105 phide or zinc cadmium

29. sulphide '1 gm mol of Zn S, The content of alkali metal is preferably
O 01 gmn mol of Li CO,, chosen to be I O to 5 10 gram atom of alkali O
06 gin mol of Mn COM, metal per gram molecule of zinc sulphide or are
mixed This mixture is heated at a tem:zinc cadmium sulphide perature
of 1150 C in an H 2 S-atmosphere 110 A As with the, known
photo-luminescent -for about one hour The material obtained :
materials of -zinc sulphide or zinc cadmium may be ground, if
necessary, before use It sulphide and the activators manganese, copper
exhibits yellow electro-luminescence.
or gold, so-called charge compensation may EXAMPLE m I be applied by
incorporating aluminium in the ' A mixture is made of 115 -_crystal
lattice =-: Thus the activator content I gin mol of Zn S, may be
chosen to be higher The aluminium 5 10- gin mol of AI(NO,),, content
-is then: preferably chosen between 10-4 gm mol of Cu(NO,),, I 0-2 and
I 0-4 gram atom of aluminium per 10-4 gin mol of Li 2 CO,.
gram molecule of zinc sulphide or zinc cad The mixture is heated in a
hydrogen sulphide 120 ^ mium sulphide atmosphere or carbon disulphide
at 1100 C.
The electro-luminescent elements in accord for one hour The substance
obtained is ance with the invention may be constructed as ground and,
if necessary, sieved before use.
follows A thin layer of the material is cormn It exhibits green
electro-luminescence.
pressed, its thickness varying with the voltage' EXAMPLE IV 125
for-which the element is intended; this layer A mixture is made of -is
sandwiched between two plates, the sur 1 gin mol, of Zn S, and faces
of which are electrically conductive on 10-2 gmn mol of Li 2 CO,
785,061 785,061 and heated at 800 C in a hydrogen sulphide atmosphere
for one hour The material obtained is ground and then heated again in
a hydrogen sulphide atmosphere for half an hour with 0 03 gin mol of
Mn(NO,)2 at 1100 C The product obtained exhibits yellow
electro-luminescence.
Instead of using lithium carbonate, use may be made of one or more of
the carbonates of the other alkali metals As in the foregoing
examples, the heating may take place in a carbon disulphide atmosphere
or in nitrogen or hydrogen sulphide charged with sulphur.
EXAMPLE V
1 gin mol of Zn Cd S is moistened with a solution of Mn(NO,)2 in a
manner such that the mixture contains O 005 gin mol of the
last-mentioned nitrate; after drying the mixture obtained is heated in
a hydrogen sulphide atmosphere at about 1000 C for about one hour The
product obtained is then mixed with 0 02 gin mol of Li CO,, heating
being then performed in the sulphurizing atmosphere at 900 C This
heating is continued for about one hour A yellow luminescing product

30. is obtained.
EXAMPLE VI
A mixture is made of 1 gin mol of Zn S, 7 10-4 gin mol of Al(NO,),
3.10-4 gin mol of Au(N Os)3 and heated in a hydrogen sulphide
atmosphere at 11500 C for one hour The product obtained is ground and
mixed with 0 04 gin mol of Li 2 CO, This mixture is heated in a carbon
disulphide atmosphere at 1080 C for 45 minutes A product is obtained
which exhibits green electro-luminescence.
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* GB785062 (A)
Description: GB785062 (A) ? 1957-10-23
Improvements in or relating to a method and apparatus for preheating feed
water in steam power plant
Description of GB785062 (A)
PATENT SPECIFICATION
: 785,062
Date of Application and filing Complete Specification: April 6, 1955.
No 10102155, Application made in Germany on April 6, 1954.
Complete Specification Published: Oct 23, 1957.
Index at Acceptance:-Class 64 ( 1), A 6 International
Classification:-F 22 d COMPLETE SPECIFICATION
Impiovements in or relating to a Method and Apparatus for Preheating
Feed Water in Steam Power Plant.
We, SIEMENS-SCHUCKERTWERKE AKTIENGESELLSCHAFT, a German Company, of
Berlin and Wemer-von-Siemens:strasse -50, 13 a Erlangen, Germany, do
hereby declare the invention, for which we pray that a patent ' may be
granted to us, and the method by which it is to be performed, to be

31. particularly described in and by the following statement: ' This
invention relates to a method and apparatus for pre-heating feed water
in a high pressure steam power plant operating on a regenerative
cycle.
a Every modern -steam power plant requires highly efficient
pre-heating in combination with a low exhaust gas temperature of the
boiler, and in the ranges of moderate pressures and temperatures this
requirement can be met without difficulty The operating conditions of
the plant at very high pressures and the attendant very high
temperatures, for example of 300 atmospheres and 550 C respectively,
initially constitute an obstacle to achieving this object in both
respects at the same time.
Installations for such high operating values must operate with various
stages of superheating, and calculations for such a boiler show that
by far the greater part of the heating surface (probably up to 80 %)
carries superheated steam, so that a low exhaust gas temperature is
not readily possible, because the high superheating temperature
necessitates a correspondingly high flue gas temperature, or in other
words the flue gas temperature cannot be lowered to a sufficient
extent Little change is produced in this respect by providing
additional' heaters for heating the combustion air, since a
correspondingly high air temperature must also be produced in such
heaters On the other hand, if the feed water pre-heating were
correspondingly increased by flue gases for the purpose of lowering'
the gas temperature, the disadvantage would arise that the efficiency
of the regenerative cycle would lPrice 3 s 6 d l be substantially
impaired particularly 'in the 45 lower stages Therefore, a new
arrangement of the heating surface' must be sought vwith which it is
possible to' lower the flue gas temperature without any detriment to
the regenerative cycle, or in any case without any 50 substantial
detriment thereto.
There is known a steam power plant of the kind comprising a main'
steam prime mover or turbine and a condenser associated therewith, in
which plant the condensate from the con 55 denser is progressively
reheated by passing the condensate through a series of heaters, and is
returned as feed water to the boilers In this known plants the
condensate from the main condenser is first heated by steam from an 60
auxiliary turbine, and is passed into an open feed water tank, from
which the condensate is passed by a circulatiing pump directly to an
economiser where the condensate is heated by the products of
combustion escaping from the 65 boilers, the condensate being
subsequently heated to boiling temperature by further steam from the
auxiliary turbine This known plant is adapted to operate at low to
moderate pressures with a boiler temperature of 70 approximately 340

32. F.
In contradistinction, one aspect of the invention provides a method of
pre-heating the feed water in a high pressure steam power plant
generating steam at temperatures in the 75 region of 550 C and
pressures in the region of 300 atmospheres, and operating on a
regenerative cycle, wherein the feed water is caused to flow from the
feed water tank through a regenerative heating stage (as hereinafter
de 80 fined) operating at high pressure, and wherein all,, or part of
the feed water is thereafter heated by the flue gases in a flue gas
preheater (as hereinafter defined), the feed water, or said part
thereof, being thereafter immediately -fed 85 to a following
regenerative stage operating at high pressure for further heating.
According to another aspect of the invention there is provided in, or
for use with a .-:igh pressure steam power plant adapted to -genieraf&
steam at temperatures in the region of 550 C and pressures in the
region of 300 atmospheres, anhd adapted io 'operate on a regenerative
cycle, apparatus for carrying into effect the method just indicated
above, wherein means is provided for'passing the feed water from the
feed water tank to the first of two or more regenerative heating
stages (as hereinafter defined) operating at high pressure, and
wherein means is located immediately between two of such high pressure
regenerative heating stages for causing all, or part of the feed water
to flow from one of such stages through a flue gas pre-heater (as
hereinafter defined) located in the boiler flue to a next succeeding
stag For a better understanding of -the invention and to show how the
same may be carried into effect, reference will niow be made to the
accompanying drawing W Vhich diagrammatically illustrates a boiler
with its associated auxiliary plant:
Referring now to the drawing there is shown a forced flow boiler 1,
and the auxiliary plant associated therewith, the boiler being adapted
to geherate steam at a temperature in the region of 550 C ahd at a
pressure in the region of 300 atmospheres The auxiliary plant
comprises a feed pump 2,-regenerative heating stages 3, 4 and 5 which
operate at high pressure, and air pre-heaters 6, 7 and 8.
By the term "regenerative heating stage" as used in this
Specification, there is meant a stage where the feed water is' heated
with a portion of steam, which has been bled off from the steam
tuirbine of the plant, in a manner known per se with steam power
plants operating on a-regenerative cycle A shut-off valve 9 is located
immediately between the high pressure regenerative heating stages 3 '
and 4 A flue gas pre-heater 10, connected to both sides of the
shut-off valve 9, is located between the air pre-heaters 7 and 8 The
water, heated in the regenerative heating stage 3, is fed, beyond this
stage, to the flue gas pre-heater 10 By the term "flue gas preheater"

33. as used in this Specification, is meant a pre-heater for the feed
water, which preheater obtains its heat source from the flue gas, the
-feed water being heated by heat exchange with the flue gas At the
pre-heater 10, the water is further heated to a predetermined extent,
for example, by 20 C, and is then returned to a point located at, or
near, the inlet to the stage 4.
In a modification, only a part of the feed water leaving the stage 3
is fed to the flue gas pre-heater 10, this part by-passing the stage 4
through a conduit 11 shown by a broken line, and being re-combined
with the main stream of feed water, at a point located beyond the
outlet of the stage 4 and before the inlet to the stage 5, after
having been t 1 appropriately further heated The conduit 11, shown in
a broken line, replaces that shown in an unbroken line, the stage 5,
thein becoming in effect the stage succeedingsstage -'t-fbr sutch
partial stream: : ' 70 The arrangement is thus adapled to extract heat
from the flue gas current by, means of an additional pre-heater 'in
order-&t': lower the waste gas temperature without - thereby
appreciably influencing the efficiency of;the 75 regenerative cycle
Naturality,-some reaction on the regenerative cycle will'be
unavoidable, because, while the feed-water is at a higher temperature
before a egenerative heating stage than when no additional heating
surface 80 is etmployed, the temperature difference in the
regenerative heating stage is reduced However, calculation si 6 ws
'that the gain in efficiency of the'-plant due to the provision of the
additional heater is greater than the reduc 85 tion in the efficiency
of the regenerative cycle.
The reaction on the regenerative cycle becomes smaller in proportion
as the extent to which the temperature in the regenerative heating
stage can be increased 90
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