This document summarizes research on reducing formaldehyde in textile finishing. It discusses hazards of formaldehyde and methods to reduce its release, including scavengers and modified cross-linking agents. Different non-formaldehyde finishes are also examined, such as Dimethyl-4,5, Dihydroxyethylene UREA and poly carboxylic acids like citric acid and butane-tetracarboxylic acid. Padding formulations using these alternatives with additives like catalysts and softeners are provided. The effects of variables like cross-linking agent concentration, curing conditions, and additives on properties like wrinkle recovery angle, tensile strength and bending length are summarized. The conclusions indicate citric acid improves properties

1. Presentations
@IIT-D
BY
VIVEK YADAV
9457631264

2. Formaldehyde free
finishing
• Submitted to
Dr. JAVED N SHEIKH
Submitted by;
VIVEK YADAV

3. Formaldehyde : Hazards
WHAT CAUSES PROBLEM ?
• Free formaldehyde that is not chemically bound to fabric
• Formaldehyde which is bound chemically to fabric but becomes free
through hydrolytic release during washing.
• Maximum conc. as per Oeko-Tex Standard 100:
•Furnishing fabrics-300ppm
•Adult clothing and skin contact items-75ppm
•Children’s items-20ppm

4. Formaldehyde
Level

5. Causes of formaldehyde release
There are three major types of formaldehyde linkages that are responsible for released
formaldehyde.
• Cellulose hemiacetal-
• Pendent N-Methylols
• Cellulose Crosslinks

6. pH effect on
formaldehyde
release
• The cellulose hemiacetals -released at neutral pH.
• The pendent N-methylols- are unstable at alkaline pH.
• Under acidic conditions,cross links are broken so all three linkages would contribute to the total
amount emitted.

7. Methods to reduce formaldehyde release
1)Scavengers
o Materials capable of reacting with monomeric
formaldehyde and tying it up.
Two categories;
a) Nitrogenous compounds;
b) Alcohols; (High boiling alcohols)
2) Methylated DMDHEU;
3) Di-ethylene-glycolated DMDHEU

8. Formaldehyde Release Comparison of Modified DMDHEU

9. NON-FORMALDEHYDE DP FINISHES

10. Dimethyl-4,5,
Dihydroxyethylene UREA
(DMeDHEU)
Pros & cons;
 This product can be absolutely
classified as a non-formaldehyde
finish.
 It is much harder to cure and the
DP properties are poor. It is more
expensive than DMDHEU.

11. Poly Carboxylic Acids

12. Cross linking of cellulose & Polycarboxylic acid

13. Citric Acid
• At high curing temperatures ,cause fabric yellowing.
• Sodium hypophosphite , suppresses fabric yellowing under standard
curing conditions.

14. Butane-tetracarboxylic Acid (BTCA)
• BTCA is the most effective of
the poly-carboxylic acids.
It provides extra edge in-
Laundering durability of the
finish , retention of fabric
whiteness,freedom from odour.
• Double the current price of
DMDHEU.

15. Additives for
desired
finishing
• CATALYST
• a. Sodium Hypophosphite
• The most effective catalyst,
DP rating and shrinkage
control equivalent to
DMDHEU have been
obtained.
• The hypophosphite is a
reducing agent. This is
beneficial for maintaining
white fabrics, however, it
discolors certain dyes
especially sulfurs.
• SOFTENERS
• PE emulsion softener
• Silicone softeners
• The elastomeric silicones
add resiliency to the fabric
improving wrinkle recovery.
The amino and epoxy
functional improve fiber and
yarn slippage, reducing the
transmission of the wrinkling
force to the fiber

16. Padding composition
• CA or BTCA (Cross Linking Agent)
• Sodium hypophosphite (Esterification Catalyst & Buffer)
• PE emulsion ( Softener )
• Micro Amino Silicone ( Softener )

17. Recipe;
CHEMICAL
S
GROUP-1 GROUP-2 GROUP-3 GROUP-4 GROUP-5 GROUP-6
CITRIC
ACID
50,100 100 - 100 100
SHP 20 20,30 20 20,30 20 20
BTCA - - 50,100 100 - -
PE
EMULSION
0,20 0,20
SILICONE
SOFTENER
- - - - 10 10

18. PROCEDURE
Pad (2 dip-2 nip ,
75 % expression)
Dry( 80˚C , 4 min
)
Cure ( 150˚C , 3
min )
Pad (2 dip-2 nip ,
75% expression)
Dry ( 80˚C , 4
min )
Cure ( 180˚C , 45
seconds )
FOR GROUP 1-5
FOR FROUP-6

19. GENERAL EFFECT ON PROCESSING
G1 G2 G3 G4 G5 G6
CITRIC ACID 50 100 100 100 100 100 100 100
SHP 20 20 20 30 20 20 20 30 20 20 20 20
BTCA 50 100 100 100
PE EMULSION 20 20 O 20 0 20
SILIONE SOFTENER 10 10 10 10 10 10
CRA 226 249 271 282 238 275 250 262 242 245 250 265
BENDING LENGTH 3.1 4.25 4.8 5.2 4 5.8 4 4.5 4.5 4.4 5.4 6.1
TENSILE 529.99 467.64 484.96 467.64 564.64 502.28 575.03 493.62 453.79 439.93 408.75 398.36

20. EFFECT OF
CITRIC ACID
SHP 20
SHP 30
50 100
CITRIC ACID
226
260
282
EFFECT OF CITRIC ACID ON CRA
SHP 20 SHP 30
SHP 20
SHP 30
50 100
CITRIC ACID
529.97
470.056
467.6468
EFFECT OF CITRIC ACID ON TENSILE
SHP 20 SHP 30

21. EFFECTS OF
BTCA
TENSILE
50 100
BTCA
564.65
502.29
EFFET OF BTCA ON TENSILE STRENGTH
BTCA 100
WITH SOFTENER WITHOUT SOFTENER
250
275
EFFECT OF SOFTENER ADDITION WITH BTCA
ON CRA
withsoftenerWithout softener

22. PE VALUE 0
PE VALUE 20
180,45 SECS 150, 180 SECS
EFFECT OF CURING
408.7579
453.7906
398.3658
439.9344
EFFECT OF CURNG ON TENSILE STRENGTH( CITRIC ACID)
PE VALUE 0 PE VALUE 20

23. Results and conclusion
• CRA- improves with the increase in citric acid conc. Higher degree
of cross linking of cotton with more citric acid .
• Breaking & Tearing Strength-The loss in strength due to cross
linking in celluloses is generally attributed to the asymmetric
distribution of load in cross linked cotton compared to one which is
not cross linked.
• Bending Length-As the citric acid conc. On cotton increases bending
length also increases. cross linking improves the dimensional stability
& affects the softness of the material negatively, which ultimately have
increased bending length.
• CA effectiveness in imparting wrinkle resistance is less than that of
tetra carboxylic acids.