The document discusses microencapsulation techniques for imparting long-lasting fragrances to textiles. It describes how microencapsulation allows fragrances to remain on fabrics for more wash cycles compared to direct application. Various microencapsulation methods are examined, including using melamine resin and poly(l-lactide) to encapsulate fragrant oils. Scanning electron microscope images show microcapsules adhered to fabrics after laundry tests. The document also explores producing polyurethane microcapsules containing perfumes via interfacial polymerization and applying them to fabrics with a foulard.

1. 03.05.2012
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2.  Fabric conditioners in the wash and during tumble-
drying; all are designed to impart a fresh aroma to the
textile.
 However, no matter the quality of the technology used to
impart the fragrance, the effect is relatively short-lived.
 Numerous attempts have been made at adding fragrances
directly to fibre and fabrics but all fail to survive one or
two wash cycles.
 Only through ‘‘microencapsulation’’ fragrances are
able to remain on a garment during a significant part of
its lifetime.
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3.  Microcapsules have the ability to be shaped in their desired form,
release of the active substance by an appropriate mechanism, stability
and adequate mechanical strength and non-toxicity of the material
itself and of its degradation production.
 They are;
 Phase-change materials
 Fragrance Applications
 Polychromic and thermochromic microcapsules
 Fire Reterdants
 Counterfeiting
 Liposomes
 Miscellaneous applications
 Especially, the protection of fragrant oil as susceptible material from
outer phase by microencapsulation is paid attention, to increase its
stability.
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5. Long self-life containing fragrant Migrin oil were prepared
by in situ polymerization from;
 Migrin oil as core material,
 melamine and formaline as wall materials,
 sodium lauryl sulphate as emulsifier
 and PVA as protective colloid.
Melamine resin microcapsules were characterized on
structure, a mean particle size and size distribution,
morphologies, thermal properties and release behavior.
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6. 1999
 0.1 M melamine and 0.25 M 37% formaldehyde in 100 ml
of distilled water
 pH 9 with 10% Na2CO3 aqueous solution.
The step of preparing the melamine-formaline precondensate
is effected under alkaline conditions.
The preferred pH range for this step is from about 7.0 to 9.0.
Even more preferably, the pH range is from about 8.5 to 9.0.
Melamine-formaline precondensate was prepared by stirring
at 70C for 10 min.
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7. SEM photographs of fragrant
cotton fabric treated with the
microcapsules after laundry
test:
(a) Original.
(b) 15 times.
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8. Poly(l-lactides) have rarely been studied as microcapsules in
industrial parts as well as medical ones, due to
 Their high transition temperature,
 Unlike poly(d- or dl-lactides) with higher degradable
properties.
 Poly(l-lactide) used as a wall-forming material.
 Span 80 as an emulsifying agent,
 PVA as a protective colloid,
 Forest-shower fragrant liquid as a core material,
 Sodium tartrate dihydrate as a penetrator,
 and Dichloromethane.
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10. SEM photographs of poly(l-lactide)
microcapsules at different steps
of stirring time:
(a) 5–70 min;
(b) 15–60 min;
(c) 30–45 min.
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11.  A 50 ml aqueous solution containing 10 wt% of Forest-shower
fragrance and 10 wt% of sodium tartrate dihydrate was
prepared.
 200 ml of dichloromethane with 2 wt% of PLLA, and 1.0 wt%
of Span 80 under a vigorous.
 Stirring rate of 3500 rpm.
 Each 200 ml portion of an aqueous solution with 2 wt% PVA
was added into the resultant w/o emulsion in two steps.
1. The stirring time after adding the first 200 ml of PVA
solution was set to 30 min,
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12.  And then the second 200 ml of PVA solution was added. At
the same time, the (w/o)/w solution was heated to about 40C
corresponding to the boiling point of solvent at the rate of
2C/min
 Dichloromethane was evaporated thoroughly from the surfaces of
w/o emulsion globules for more 2 h to make the interfacial
precipitation of PLLA onto the surfaces of the core materials.
 The obtained PLLA microcapsules containing a core material and a
penetrator were washed with distilled water, filtered, and dried in a
vacuum oven at 40C for at least 12 h.
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13.  Fragrant functional fabrics were prepared by the printing treatment of microcapsules
on cotton fabric, and SEM photographs after laundry tests of original and 15 times are
shown in Figure.
 As shown in the pictures, the fabric is coated uniformly by printing paste with
microcapsules, and has almost uniform particles on it. Moreover, it is convinced that
the particles below 10 µm are applicable for the preparation of functional fabric.
 Most of the particles, especially much finer ones with mean diameter below 5 µm
remain even after the laundry test of 15 times.
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14. The materials used for the formulation of perfume were:
 Limonene (lemon scent – LMN) (Sigma–Aldrich),
 Methyl cedryl ketone (vetiver scent – MCK) (Sigma–Aldrich),
 Methyl dihydrojasmonate (jasmine scent – MJD) (Sigma–Aldrich)
 And 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-
enzopyran solution (galaxolide); 50% in diethyl phthalate (dep)
(musk scent) (Sigma–Aldrich).
REACTANTS
 Hexamethylene-1,6-diisocyanate (HMDI) (Bayer, Desmodur W) as the
isocyanate;
 Dibutyltin dilaurate (DBDTL) (Sigma–Aldrich) as the catalyst;
 Polyethylene glycol 400 (PEG 400) (Sigma–Aldrich) as the polyol;
 Ethylenediamine (EDA) (Panreac) as amine I;
 Hydrazine monohydrate (HYD) (Sigma–Aldrich) as amine II;
 Polyvinyl alcohol (PVA) (Celanese Chemicals, Celvol 840) as protective
colloid
 Triton CA (Dow Company) as emulsifier. 03.05.2012 14

15.  PUU microcapsules were prepared by interfacial polymerization. The
organic phase (OP) was formed by mixing the perfume and HMDI.
 The first aqueous phase (AP1) was constituted by water and PVA (used
to stabilize the droplets and thereafter set up the microcapsules particle
size distribution). Emulsion was formed by adding OP into AP1.
Emulsification was performed at 11,000rpm during 3min with an
ultraturrax (IKA T25 digital).
 Second aqueous phase , constituted by water, polyol (PEG 400) and
catalyst (DBTDL),was prepared and transferred to the previously
mentioned emulsion to form the polyurethane (PU) wall. Interfacial
polymerization was performed in a batch reactor (IKA LR-2.ST) at 80
C using a stirring rate of 100rpm during 1 h.
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16.  Third aqueous phase (AP3) was added to proceed with urea formation.
 This stage takes 1 h. Since the reaction with EDA presents
incomplete isocyanate conversion, a final aqueous phase (AP4)
containing a more reactive amine (HYD) was added and let to react
during 1 h.
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17. Experimental set-up for the
production of microcapsules
by interfacial
polymerization:
(1) reactor vessel;
(2) ultraturrax;
(3) overhead stirring
drive and
(4) thermostatic bath.
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18. Schematic representation of the microcapsules application process in
fabrics using a foulard.
1. Untreated fabric
2. Microcapsules bath
3. Squeezing zone
4. Drying and curing
5. Fabric treated containing microcapsules.
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20. 1. Hong K, Park. S, Materials Chemistry and Physics 58 (1999) 128-131
(Melamine resin microcapsules containing fragrant oil: synthesis and
characterization)
2. Hong K, Park S. Polymer 41 (2000) 4567–4572 (Preparation of poly(l-
lactide) microcapsules for fragrant fiber and their characteristics)
3. Nelson G, International Journal of Pharmaceutics 242 (2002) 55–62
(Application of microencapsulation in textiles)
4. S.N. Rodriguesa, I.M. Martinsa, I.P. Fernandesb, P.B. Gomesa,c, V.G. Matac,
M.F. Barreirob, A.E. Rodriguesa , Chemical Engineering Journal 149 (2009)
463–472 (Microencapsulated perfumes for textile application)
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21. 