U.S. patent application number 11/138859 was filed with the patent office on 2005-12-01 for process for depositing microcapsules into multifilament yarn and the products produced.
Invention is credited to Berlinger, Mathias.
Application Number | 20050262646 11/138859 |
Document ID | / |
Family ID | 35124322 |
Filed Date | 2005-12-01 |
United States Patent
Application |
20050262646 |
Kind Code |
A1 |
Berlinger, Mathias |
December 1, 2005 |
Process for depositing microcapsules into multifilament yarn and
the products produced
Abstract
The invention is directed to a process for depositing additives
into a yarn having multi-filaments comprising steps of; separating
the multi-filaments of the yarn into individual filaments while
winding the yarn; injecting the additive onto the individual
filaments; and promoting the individual filaments of the yarn to
close up one against the other whereby the additive are entrapped
within the multi-filaments. The invention also concerns an
apparatus for depositing microcapsules into a multi-filaments of a
yarn and the multifilament yarn produced.
Inventors: |
Berlinger, Mathias;
(Montmagny, CA) |
Correspondence
Address: |
OGILVY RENAULT LLP
1981 MCGILL COLLEGE AVENUE
SUITE 1600
MONTREAL
QC
H3A2Y3
CA
|
Family ID: |
35124322 |
Appl. No.: |
11/138859 |
Filed: |
May 27, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60574942 |
May 28, 2004 |
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Current U.S.
Class: |
8/186 |
Current CPC
Class: |
D02G 3/40 20130101; D06M
23/12 20130101 |
Class at
Publication: |
008/186 |
International
Class: |
D06M 013/322 |
Claims
1. A process for depositing additives into a yarn having
multi-filaments comprising steps of; separating the multi-filaments
of the yarn into individual filaments while winding the yarn;
injecting the additive onto the individual filaments; and promoting
the individual filaments of the yarn to close up one against the
other, whereby the additives are entrapped within the
multi-filaments.
2. The process of claim 1, wherein the additives are microcapsules
in a range of diameter from 0.1 to 200 .mu.m, wherein the
microcapsules comprise an outer wall and a central core.
3. The process of claim 1, wherein the steps are performed on the
yarn during operation of a textile winding machine.
4. The process of claim 3, wherein the textile winding machine is
selected from the group consisting of a winder, a texturing machine
and a twister.
5. The process of claim 4, wherein the texturing machine is a false
twist texturing machine.
6. The process of claim 4, wherein the texturing machine is an air
texturing machine.
7. The process of claim 1, wherein separating multi-filaments of
the yarn is produced by an un-tensioning of the yarn between two
shafts of a textile winding machine.
8. The process of claim 1, wherein separating of multi-filaments of
the yarn is produced by a gas jet directed at the yarn.
9. The process according of claim 1, wherein injecting the additive
onto the individual filaments is via a liquid jet.
10. The process according to claim 1, wherein the yarn is selected
from the group consisting polyesters, polyamides, polypropylene,
polyethylene, aramids, synthetic multifilament yarns and artificial
multifilament yarns.
11. The process according to claim 1, wherein the yarn having
multi-filaments is produced by texturing a Partially Oriented Yarn
(POY) or Fully Oriented Yarn (FOY).
12. The process of claim 2, wherein the central core comprises a
material that is chemically, physico-chemically or biologically
active, and the material is selected from the group consisting of
bioactive agents; drugs and pharmaceuticals; enzymes; dyes and
pigments; fragrances; moisturizing agents; bleaching agents;
depilatory agents; UV-block agents; softening agents; elasticity
improving agents; flame-, moth-, crease- and soil-proofing agents;
water repellent agents; anti-shrinking agents; cross-linking
agents; magnetic particles; thermochromic, photochromic,
electrochromic, piezorochromic, solvatechromic, carsolchromic
materials; insects repellents; pesticides; static
electricity-controlling or reducing agents; electrically conductive
materials; radar-absorbing materials; reflecting particles;
heat-absorbing and/or heat-releasing phase change agents;
decontamination agents; zeolites; and activated carbon; and
combinations thereof.
13. The process of claim 2, wherein the outer wall is a natural,
semi-synthetic or synthetic, high molecular weight material such as
gelatin; Arabic gum; agar agar; alginic acid and salts thereof;
fatty acids; cetyl alcohol; collagen; chitosan; lecithins; albumin;
starch; dextran; polypeptides; cellulose and chemically modified
cellulose; polyacrylates; polyvinyl alcohol; polyvinyl pyrrolidone;
polyurethane; polyolefin; polyamide; an aminoplast; polyester;
polysaccharide; silicone resins; epoxy resins and formaldehyde
resins.
14. An apparatus for depositing microcapsules into a yarn having a
plurality of filaments, the apparatus comprising; a supply spool, a
take-up spool winding the yarn in a first direction between the
supply spool and the take-up spool, a means for separating the yarn
at, at least one separating point disposed between the supply spool
and the take-up spool, the means for separating the yarn thereby
exposing the filaments, and at least one nozzle proximate the
separating point, the at least one nozzle injecting a liquid onto
the filaments in a second direction transverse the first direction,
the liquid having the microcapsules suspended therein and thereby
injecting the microcapsules.
15. The apparatus of claim 14, wherein the at least one nozzle is
located downstream of the separating point.
16. The apparatus of claim 14, comprising; a body disposed between
the two spools, the body defining an opening through which the yarn
winds in the first direction and the at least one nozzle oriented
to intersect the opening, and thereby directing the liquid having
the microcapsules towards the yarn.
17. The apparatus of claim 14, wherein the means of separating the
yarn comprising a first and a second shaft, the shafts disposed
between the supply and the take-up spool, the first shaft winding
the yarn at a first speed and the second shaft winding the yarn
from the first shaft rotating at a second speed lower than the
first speed, thereby producing an un-tensioning of the yarn.
18. The apparatus of claim 16, wherein the means of separating the
yarn comprises at least one aperture defined in the body, the
aperture connected to a supply of pressurized gas, passage of the
gas through the aperture producing a gas jet directed at the yarn
transverse the first direction.
19. The apparatus of claim 18, wherein the aperture directs the gas
jet to produce an angle when intersecting the first direction, the
angle varying from perpendicular to the first direction, to
30.degree. from the perpendicular to the first direction.
20. The apparatus of claim 18, wherein the at least one nozzle, is
two nozzles.
21. A multifilament yarn having a cross sectional perimeter, the
yarn comprising: individual filaments interconnected together to
produce the yarn; and microcapsules having a range of diameter of
0.1 to 200 .mu.m on the individual filaments within the perimeter
of the yarn.
22. The yarn of claim 22, wherein the microcapsules comprise an
outer wall and a central core.
23. The yarn of claim 23, wherein central core comprises a material
that is chemically, physico-chemically or biologically active and
the material is selected from the group consisting of bioactive
agents; drugs and pharmaceuticals; enzymes; dyes and pigments;
fragrances; moisturizing agents; bleaching agents; depilatory
agents; UV-block agents; softening agents; elasticity improving
agents; flame-, moth-, crease- and soil-proofing agents; water
repellent agents; anti-shrinking agents; cross-linking agents;
magnetic particles; thermochromic, photochromic, electrochromic,
piezorochromic, solvatechromic, carsolchromic materials; insects
repellents; pesticides; static electricity-controlling or reducing
agents; electrically conductive materials; radar-absorbing
materials; reflecting particles; heat-absorbing and/or
heat-releasing phase change agents; decontamination agents;
zeolites; and activated carbon; and combinations thereof.
24. The yarn of claim 23, wherein the yarn is selected from the
group consisting polyesters, polyamides, polypropylene,
polyethylene, aramids, synthetic multifilament yarns and artificial
multifilament yarns.
Description
RELATED APPLICATIONS
[0001] The present application claims priority on U.S. provisional
application No. 60/574,942 filed on May 28, 2004, the contents of
which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a process for providing
additives to yarn made of multifilament textiles.
DESCRIPTION OF THE PRIOR ART
[0003] Micro-encapsulation has been used in the textile industry
since the early 1990's. Many textile manufacturers are looking into
the use of microcapsules to functionalize their products by giving
textiles: a durable scent; a means for applying a cosmetic, such as
a body lotion, or a pharmaceutical product.
[0004] Microcapsules applied to textile materials impart
characteristics which depend on the nature of the active substances
present inside the microcapsules. The large number and variety of
active substance that can be used is further proof of the
usefulness of the micro-encapsulation technique in the fabrication
of different textiles which have many applications.
[0005] Microcapsules have been applied to the textile webs (woven,
knitted and no woven fabrics), fibers, and monofilaments or
multifilament yarns. The majority of described techniques for
applying of microcapsules to the textiles is designated for the
webs finishing.
[0006] Impregnation is one method of web/fabric finishing. The web
is placed in a treatment bath, such as a "pad" machine, which
contains both charged microcapsules and a binder. Optionally
products include: dispersing agents; pressure absorbing agents;
softening agents and surfactants alone or in combination may also
be added. The treated fabric must be dried and/or cured (soaking
process); or squeezed and dried and/or cured (padding process). The
binders anchor the microcapsules to the fabric. Suitable binders
for microcapsule finishing include: polymeric melamine compounds;
polymeric glyoxal compounds; polymeric silicone compounds;
polyalkylene glycols; poly(meth)acrylates; polymeric fluorocarbons
and epichlorohydrin-crosslinked polyamidoamines. The surfactants
present in the bath facilitate interactions between the components
of the bath and the fabrics and improve the "fabric hand" after
treatment. The drying/curing processes are necessary for
water/solvent evaporation from the treated fabric and in some cases
for activating some binders requiring higher temperature to bind
the web/fabric.
[0007] The impregnation method (padding or soaking) is described in
U.S. Pat. No. 4,882,220 where microcapsules containing a fragrance
are applied to a fabric by soaking, padding and printing processes.
In U.S. Patent Application 2002/0166628, the soaking method is
disclosed. Canadian Patent Application 2,483,279 describes applying
microcapsules by soaking and padding. Finishing of fabrics with
microcapsules containing skin-conditioning agents by soaking,
padding, coating, spraying and printing method is described in U.S.
Pat. No. 5,232,769. Japan Patent document JP 11012953 describes the
method for obtaining an anti-inflammatory and/or analgesic textile
material by textile finishing with microcapsules containing a
biological active agent.
[0008] Microcapsules have also been applied to textile fabrics
using a coating process. The fabric to be treated is exposed to
microcapsules coated with the binder in a coating machine. Here any
excess of coated microcapsules is eliminated from the fabric, for
example, by a knife system. The coated fabric is then dried and/or
cured. This method is described in U.S. Pat. No. 3,479,811, where
expandable micro-spheres are incorporated on the surface of the
fabric by the coating process. Canadian Patent 1240883 describes a
coating process for microcapsules containing thermo chromic
pigments. The coating method to functionalize fabric by
microcapsules is also described in Korean Patents KR 2002056779 and
KR 2001069654. Electrically conductive and electromagnetic
radiation absorptive fabric was obtained by microcapsules coating
described in U.S. Patent Application 2004/0212.
[0009] Other methods of applying microcapsules to textile fabrics
include: spraying described in International Patent WO 00/05446, in
Korean Patent KR 2002082692 and in two Japan Patents JP2000178873
and JP02200602; printing described in European patent EP 1231319
printing allows only selected areas of textile fabric to be
functionalized; and doping a spinning solution with the
microcapsules and extruding the fibers already finished, as
described in U.S. Pat. No. 3,852,401.
[0010] All these methods for applying microcapsules on yarns
require an additional treatment step which may be long and
laborious. Thus, there is a need for a process for applying
microcapsules to yarn "on-line" during a normal finishing process
of yarns.
[0011] Furthermore with the yarn treatments discussed, only the
yarn surface is coated by binder and microcapsules. This gives the
fabric a "rough hand" which is not acceptable for many products
like, especially products which will be in contact with the body.
Thus, there is also a need for microcapsules finishing yarns which
can be used which have a "fabric hand" which is soft final
products.
SUMMARY OF THE INVENTION
[0012] In one aspect of the invention there is a process for
depositing additives into a yarn having multi-filaments comprising
steps of; separating the multi-filaments of the yarn into
individual filaments while winding the yarn; injecting the additive
onto the individual filaments; and promoting the individual
filaments of the yarn to close up one against the other, whereby
the additives are entrapped within the multi-filaments.
[0013] According to another aspect of the invention there is an
apparatus for depositing microcapsules into a yarn having a
plurality of filaments, the apparatus comprising; a supply spool, a
take-up spool winding the yarn in a first direction between the
supply spool and the take-up spool, a means for separating the yarn
at, at least one separating point disposed between the supply spool
and the take-up spool, the means for separating the yarn thereby
exposing the filaments, and at least one nozzle proximate the
separating point, the at least one nozzle injecting a liquid onto
the filaments in a second direction transverse the first direction,
the liquid having a the microcapsules suspended therein and thereby
injecting the microcapsules.
[0014] According to yet another aspect of the invention there is a
multifilament yarn having a cross sectional perimeter, the yarn
comprising: individual filaments interconnected together to produce
the yarn; and microcapsules having a range of diameter of 0.1 to
200 .mu.m on the individual filaments within the perimeter of the
yarn.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Further features and advantages of the present invention
will become apparent from the following detailed description, taken
in combination with the appended drawings, in which:
[0016] FIG. 1. is a schematic representation of the process steps
of an embodiment of the present invention where Partially Oriented
Yarn (POY) is used as a starting material and the aspect of the
filaments of the POY during processing is represented;
[0017] FIG. 2 is a schematic representation of the process of
another embodiment of the present invention multiple Partially
Oriented Yarns (POYs) are the starting material and produce a
multifilament yarn which is textured by an air jet device and one
POY being overfed onto the other;
[0018] FIG. 3 is a schematic representation of a system of
injection of a dispersion of the microcapsule according to one
embodiment of the present invention;
[0019] FIG. 4 is a cross section of a device for the deposition of
the additives according to one embodiment of the present invention;
and
[0020] FIG. 5 is a micrograph of microcapsules on the filaments
within a Draw Textured Yarn of one embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] The invention is applicable to manmade textiles that include
but are not limited to: polyesters, polyamides (nylons), aramids,
polypropylene, and other synthetic and/or artificial multifilament
yarns. Multifilament yarns are understood to be composed of a
plurality of filaments.
[0022] The following terms are included to clarify the definition
of the terms found in the application.
[0023] The term yarn is defined as a continuous bundle of textile
fibers, filaments or materials in a form suitable for intertwining
to produce a textile fabric. A multi-filament yarn has two or more
individual filaments intertwined. There are many forms of yarn such
as; spun yarn where a number of fibers are twisted together;
zero-twist yarn, where the filaments are laid together without any
twist; twist yarn which includes a number of filaments with a
twist.
[0024] Winding is understood to mean a process of transferring yarn
or thread from one type of package to another to facilitate
subsequent processing. The package or spool is understood as the
forms for winding yarn, most of these packages are flangeless to
allow high speed of unwinding.
[0025] There are two types of winders precision and drum winders.
Precision winders are used for the most part with filament yarns,
they include a cam driven traverse and an oscillating motor moving
a traverse, that synchronize the spindle to produce packages with a
wound diamond-pattern. Drum winders, including propeller type
systems, are used principally for spun yarn, where a frictional
contact drives the package.
[0026] The term texturing is understood as a process that produces
random loops, crimping, or other operation which increases the
texture of a yarn. These operations also increase insulation value,
warmth and absorption of the yarn, and provides a different texture
to the surface of a yarn. The present process of deposition of
microcapsules requires the application of the microcapsules onto a
textured yarn. Many types of textured yarns are known to the
skilled practitioner they include: Draw Texture Yarn (DTY) and Air
Textured Yarn (ATY). As will be described, non-textured or flat
yarns may be used as a starting material.
[0027] Reference is made to a textile winding machine which is
understood to include: a winder; a texturing machine, or a twister.
A preferred embodiment of the texturing machine is a false twist
texturing machine or an air texturing machine.
[0028] The textile handling machines listed above is not limitative
and the skilled practitioner would understand that other textile
winding machines may be used. Textile handling or processing
includes: spinning; plying; twisting; texturing and coning. Textile
processing includes many mechanical operations used to translate a
textile fiber or yarn to a fabric or other textile material and
would be understood by the skilled practitioner.
[0029] Micro-encapsulation is a technique of enclosing chemically,
physico-chemically or biologically reactive material in tiny
microcapsules from which the material can be released under
particular conditions.
[0030] A microcapsule is composed of an outer wall or shell
comprising a natural, semi-synthetic or synthetic, high molecular
weight material such as gelatin; Arabic gum; agar agar; alginic
acid and salts thereof; fatty acids; cetyl alcohol; collagen;
chitosan; lecithins; albumin; starch; dextran; polypeptides;
cellulose and chemically modified cellulose; polyacrylates;
polyvinyl alcohol; polyvinyl pyrrolidone; polyurethane; polyolefin;
polyamide; an aminoplast; polyester; polysaccharide; silicone
resins; epoxy resins and formaldehyde resins. In a preferred
embodiment the aminoplast is a melamine. Microcapsules have a
particle diameter in the range from to 0.1 to 1000 .mu.m,
preferably between 0.1 to 200 .mu.m, and most preferably 0.5 to 20
.mu.m.
[0031] The process of the present invention is continuous, rapid,
and substantially dry, it is executed over a short period of time,
of as little as, {fraction (1/10)} to 1 sec, while the classic
soaking process may require from 2 to 3 hours, furthermore the dry
conditions (dry yarn) provides good fixation of microcapsules. The
process of the present invention is applicable to many kinds of
yarn, allows for flexibility by allowing for the use of short runs
of yarn, as well as, lower quantities of actively charged
microcapsules to achieve the target activity of final product. Like
all other yarns, the yarn of the present invention has a length and
a perimeter. However, with the yarn produced by the process of the
present invention, microcapsules are found within the perimeter of
the yarn, not only on the perimeter, or outer surface, as with some
processes. The present process is eco-friendly as active
ingredients are recycled in the system and chemical losses are
minimized, thus also improving cost effectiveness. The yarns
finished by the process of present invention have a substantially
uniform microcapsules distribution. The textiles webs fabricated
from yarns of the present invention have a "soft hand" and are
applicable to textile webs which gradually release encapsulated
active substances and which may be in permanent contact with
wearer's skin and body.
[0032] FIG. 1 represents one embodiment of the process of the
present invention for producing a multifilament Draw Textured Yarn
(DTY) including deposited microcapsules according to the present
invention in a textile winder. The process steps, as well as the
schematic nature of the filaments of the yarn during the processing
is represented in FIG. 1. The direction of movement of the yarn
during processing is indicated by the arrow 2. A supply spool 10 of
a multi-filament partially oriented yarn (POY) 12 is fed from the
spool 10 to a first shaft 20 also called an input feeding shaft or
roll, rotating at a given speed. From this shaft 20 the yarn is fed
to a second shaft or roll 60, which turns at a higher speed than
the first shaft 20. Thus, the yarn 12 is simultaneously drawn, its
length is increased and diameter diminished and twisted. The yarn
12 is twisted after the first shaft 20 by a friction device, such
as a set of spindles or friction discs 50 which produce a twisted
yarn 22. The yarn 22 enters a heater 30 where its temperature is
increased so that the yarn 22 is thermo-fixed (130.degree. C. to
500.degree. C.). The heater 30 is followed immediately by a cooling
zone 40 which may be at room temperature or may be cooled below
room temperature. The cooler 40 has a smooth curved surface which
facilitates the cooling and reduces the likelihood of breaking very
fine filaments of yarn. The yarn 52 leaving the friction discs 50
may in some cases be straightened as represented in the FIG. 1.
[0033] The tension between the second shaft 60 and the first shaft
20 caused by the greater speed of the second shaft 60 causes the
filaments of the yarn 22 to be elongated while heated. The tension
of the drawn yarn 62 leaving the second shaft 60 is lower due to
the lower speed of shaft 80 (or the "2 bis" roll) in relation to
shaft 60.
[0034] This reduction in speed is permissible because there is a
reduction in the length of the yarn produced by the bulking of the
yarn and its stretch behaviour. The yarn 62 has become somewhat
crimped. Thus the operation of twisting and heating the yarn
produces curling of the filaments lower than that of shaft 60,
permitting retraction and bulking of the entire multifilament yarn.
It should be noted that this reduction in tension or un-tensioning,
causes the filaments in the yarn to separate to some degree.
Therefore, the speed of a third shaft or "2-bis" roll, 80 which
rotates at a marginally lower velocity than the second shaft 60, is
related to the percentage of reduction of overall length of the
yarn. Thus the shafts 60 and 80 serve as a means of separating the
yarn into individual and exposed filaments.
[0035] The yarn travels or winds through an opening or passage
extending through the body of device 70 in the direction indicated
by the arrow 2. The filament in yarn 62 are separated as well as,
possibly interlaced or intermingled in the device 70, where in a
preferred embodiment there is an air jet 72. The yarn 62 enters the
device 70 where the air jet 72 (at a pressure as much as 100 psi)
is directed at the yarn 62 in a perpendicular or nearly
perpendicular direction with respect to the of movement of the yarn
2. The yarn 62 comes into contact with air vortices produced by the
air jet 72 which act as a means of separating of the filaments of
the yarn 62 in a preferred embodiment. The air jet 72 enters the
device 70, through an aperture transverse to the opening through
the device 70. As the filaments move out of the jet 72 due to the
movement of the yarn, they re-orient back onto each other, may
produce braids or knots at regular intervals within the yarn 76.
The skilled practitioner would understand that a gas jet, such as
the air jet 72, are produced by a gas or fluid passing through an
aperture, a hole, or a nozzle, and possibly via other devices such
as a valve, which produces a very high velocity gas/fluid stream.
The skilled practitioner would understand that the air in the air
jet 72 may be replaced with another suitable gas or combination of
gases such as an inert gas like nitrogen, helium, neon or argon if
required. In a preferred embodiment the air/gas jet 72 may also be
heated.
[0036] The device 70 includes a hole or nozzle for a stream 74
through which suspended microcapsules are injected into the device
70 at the point close to where the filaments have been separated
from one another, into individual filaments, while winding through
the device 70. This nozzle is located along the winding path of the
yarn, and is located proximate to a point where the filaments have
been separated. In a preferred embodiment the nozzle producing the
liquid jet 74 is located downstream, with respect to the direction
of travel of the yarn 2, of this yarn separating point. In a
preferred embodiment, the microcapsules liquid jet 74 leaves a
nozzle intersecting the yarn winding opening, the intersection of
liquid nozzle and yarn winding opening is substantially opposite
and/or slightly downstream of an aperture for an air jet 72. The
liquid nozzle and the aperture may both be transverse to the yarn
winding opening through the device 70. In a preferred embodiment
the aperture for the jet 72 and the nozzle for the liquid stream 74
are perpendicular to the wall of the opening of the device. The
stream or spray 74 of microcapsules will be injected into and
adhere to the separated individual filaments and coat the filament
surfaces. In another preferred embodiment, there are two air jets
and two liquid jets and each air and liquid jet is in close
proximity to one another and are situated along the wall of opening
through the device 70. Furthermore, the orientation of the nozzles
along the wall opening may be directed at the winding yarn so that
the jet makes a perpendicular angle to the direction of travel of
the yarn 2. The angle made between the direction of the liquid jet
74, the air jet 72 when either jet leaves the nozzle in a
substantially straight line, and the direction of travel may vary
by 30.degree. from the perpendicular and as much as 45.degree. from
the perpendicular.
[0037] As the filament continues to wind through the jet device 70
it leaves the vortices produced by the air jet 72 and the filaments
close up upon themselves thus sealing the microcapsules within the
yarn. This braided, interlaced or intermingled and textured yarn 76
thus produced, includes microcapsules within the structure, as well
as on the external surfaces of the yarn 76. The microcapsules are
also found within the narrow hollows of the intermingled or
entangled filaments. Because the microcapsules make it into these
grooves or channels of the specific filaments of yarn, the yarn is
expected to retain the microcapsules and therefore the properties
of the materials within the microcapsules for a longer period of
time, than in processes where the yarn is coated only on the
surface. FIG. 5 is a electro-micrograph of a yarn where the
individual filaments include microcapsules.
[0038] The additives may be injected into the yarn directly after
the shaft 60 without the aid of an air jet 72. But the use of an
air jet improves the process by separating the individual filaments
of 52 before inserting the microcapsules. The jet 72 separates the
filaments to a greater extent than with only un-tensioning due to
the effects of the operation of the shafts alone, and is thus a
preferred mode of operation for this invention.
[0039] Throughout the disclosure the words; additive, microcapsule
and nanocapsule are used interchangeably, each of which can have a
single constituent or multiple components. The additives are
preferably microcapsules in a range of diameter from 0.1 to 1000
.mu.m, preferably between 0.1 to 200 .mu.m, and most preferably 0.5
to 20 .mu.m, where the microcapsules have an outer wall and a
central core. The wall is adapted to bind to the filaments. In a
preferred embodiment the outer wall of the microcapsule fuses with
the individual filament by the action of heat and/or with the
binder. The central core of the complete particle or microcapsule,
may include a substance or material which is chemically,
physico-chemically or biologically active or simply cosmetic. These
materials may be topical skin lotions or medicines.
[0040] The chemically, physico-chemically or biologically active
material enclosed inside of microcapsule may include the following
types of substances: bioactive agents, drugs and pharmaceuticals;
enzymes; dyes and pigments; fragrances; moisturizing agents;
bleaching agents; depilatory agents; UV-block agents; softening
agents; elasticity improving agents; flame-, moth-, crease- and
soil-proofing agents; water repellent agents; anti-shrinking
agents; cross-linking agents; magnetic particles; thermochromic,
photochromic, electrochromic, piezorochromic, solvatechromic,
carsolchromic materials; insects repellents; pesticides; static
electricity-controlling or reducing agents; electrically conductive
materials; radar-absorbing materials; reflecting particles;
heat-absorbing and/or heat-releasing phase change agents;
decontamination agents; zeolites; activated carbon; and
combinations of these substances.
[0041] The yarn 76 continues to the third shaft 80 and the fourth
shaft (also be called the delivery or nip roll), 100. In between
the two rolls 80, 100 a heater 90 may be included. The optional
heater 90, may evaporate any solvents or aqueous component injected
with the microcapsules suspension and also helps to further bind
the microcapsules to the filaments. The fourth set of shafts 100,
serves to control overfeed in the temperature setting zone, before
the yarn 102 is drawn or wound onto the take-up spool 112 with the
aid of take-up shaft 110.
[0042] It is noted that many variations of location for the device
70 and the injection of microcapsules is possible. The device 70
has been located directly after the shaft 60 without the inclusion
of an air jet, as well as, directly after the second heater 90 and
before the nip roll 100. Microcapsules have successfully been
applied and inserted into the multi-filaments of the yarn at
various locations.
[0043] The deposition process of the present invention requires
that the yarn be textured before the separation and deposition
occurs. However, the starting yarns may be textured, immediately
upstream of the process of the present invention, and this is
described in FIG. 2. Thus Partially Oriented Yarn (POY), Fully
Oriented Yarn (FOY). and Low Oriented Yarn (LOY) and combinations
thereof, which are not textured yarns may serve as starting
products but they must be textured before the microcapsules are
deposited. In the mode proposed in FIG. 2, more than one spool of
POY, FOY, LOY or combinations thereof is fed in a winding machine.
Each POY or other yarn, passes over a heater into an air jet
device. FIG. 2 is an option of texturizing POY into a
multi-filament yarn before the deposition of the
additive/microcapsule. The direction of the movement of the yarn in
FIG. 2 is indicated by the arrow number 3. By the process of this
invention spools (150, 160) feed POY onto feed shafts (170, 180)
the filaments are drawn by a second set of shafts (220, 230) at a
greater speed through a similar series of steps which include a
heating step (190, 200) with the POY. These POY yarns can be
further textured such that the feed rate of the yarns from the
second shafts 220 and 230 are different in the order of -10% to
+200% thus the yarn 231 leaving the shaft 230 may be fed at a speed
as much as 200% greater than the yarn 221 leaving the shaft 220.
The yarn 221 is called the core yarn while the yarn 231 is called
the effect yarn in entering the air jet device 240 the air jet 242
has a tendency of enveloping the effect yarn 231 over the core yarn
221, to give a multiplicity of loops and thus the POY yarn which
was only partially oriented is now a multi-filament yarn ready to
have additives incorporated by the process of the present invention
through the hole for jet 264.
[0044] Due to the high level of looping of the effect yarn 231
around the core yarn 221, the type of process arrangement often
includes two stabilizing rollers 250 and 270, which reduce and
stabilize the yarn produced to a more uniform thickness. In a
preferred embodiment the microcapsule jet device 260, optionally
including another air jet 262, is placed between the two sets of
stabilizing rollers 250 and 270. As in previous examples the liquid
jet 264 incorporates additives within the yarn, with individual
filaments separated by un-tensioning of the yarn or by the action
of an air jet.
[0045] The multi-filament yarn leaving the jet device 260 and
roller 270, including microcapsules may once again be heated to
evaporate the aqueous phase and so as to further adhere the
microcapsules to the now multi-filament texturized yarn in heater
280. The heater 280 is between rolls 270 and 290. From the roll
290, the yarn is wound onto the take-up spool with the aid of
take-up shaft. The take-up spool and shaft are not illustrated in
FIG. 2. Thus various methods of generating the textured
micro-filament yarn required for the incorporation of microcapsules
by the process of this invention are possible and would be clear to
the skilled practitioner, and be used for the deposition of
additives by the process of the present invention.
[0046] The skilled practitioner would also understand that other
types of yarn using similar arrangements of textile handling
equipment may generate multifilament textured yarn.
[0047] Preparation of the Suspension of Microcapsules
[0048] FIG. 3 represents a tank 300 which includes a mechanically
or magnetically driven agitator 310 where the suspension of
microcapsules in aqueous phase is prepared. The tank 300 may
include a means 320 which heat the suspension of particles in a
controlled manner. The suspension is re-circulated from the tank
300 by means of a pump 330. The pump 330 is selected from the group
of pumps which are designed to minimize the shear and thus the
breakage of microcapsules in suspension. The types of pumps
applicable are selected from the group consisting of peristaltic,
diaphragm, progressing cavity, and centrifugal disc pumps. The
skilled practitioner would understand that this group of pumps is
not limitative and other pumps minimizing the shearing of
microcapsules may be employed. The suspension is circulated in a
piping or tubing system 332 to the typical jet device 370 where the
multi-filament yarn 360 will be intermingled by the action of the
air jet 372 and coated by the action of the jet 374 of
microcapsules. The suspension is not completely consumed by
spraying onto the filaments and is collected in a vessel 380 for
re-circulation by pump 339 back to the original reservoir 300.
[0049] The suspension of microcapsules may contain components that
have a tendency to block jet 374 which requires periodic cleaning
or de-blocking of the hole through which liquid jet passes during
operation by periodic maintenance. This periodic cleaning may be
performed by a mechanical device or through the selection of
self-cleaning jets.
[0050] FIG. 4 illustrates a cross sectional view of a preferred
embodiment of the present device 470 used to deposit additives such
as microcapsules and nano-capsules into the filaments of a textured
yarn. The device includes a body 400 defining a central opening or
hole 405 which passes through the device 470, in a preferred
embodiment the hole is cylindrical. The hole 405 is adapted to
allow: the passage of textured yarn 62 at high speed into and
through the opening 405, and the exit of the intermingled yarn 76
at the outlet end of the opening 405. The direction of the movement
of the yarn 62 through the device 470 is indicated by the arrow
4.
[0051] The wall of opening 405 is intersected by at least one hole
for a liquid jet 474, which due to an un-tensioning caused either
by the slight reduction of speed through the device, or by the
inclusion in a preferred embodiment of an aperture for an gas or
air jet 472 which will open the multifilament and allow the
deposition of additives within the individual filaments of the yarn
62. Upon leaving the vortices of the air jet 472 the individual
filaments of the yarn will have a tendency to close up one against
the other, but the winding of the yarn through the rolls will
further promote this closing of the individual filaments of the
yarn. FIG. 4 represents a preferred embodiment which includes two
liquid holes or nozzles 473, 475, which produce two liquid sprays
(or jets) 474, 476. The number and placement of liquid holes can be
increased or decreased depending on the speed of the yarn through
the device 470, and would be understood by a skilled practitioner.
In a preferred embodiment the hole(s) 473, (475), are liquid
nozzle(s) and are located opposite an aperture 471 for the air jet
472 along the wall of the opening. The air jet hole 471 and the air
jet 472 are once again used to separate the filaments of the yarn.
This embodiment of the device has mechanical means for cleaning the
liquid nozzles by a system of plungers 491 and 493 which scrap any
build-up from the top of the liquid holes 473, 475. Arrow 495
represents the direction of the movement of the plungers 491, 493.
In FIG. 4, one of the plungers 491 is in a retracted position,
while plunger 493 is in an extended position removing any deposits
of additives which may have built up in the hole 475. Other means
for the cleaning of the nozzles 473, 475 can be envisaged and
include the redirection or the addition of a the high pressure air
jet towards the top of the liquid jets 473, 475. Many such
alternatives are available and known to the skilled practitioner.
In FIG. 4 the deposited microcapsules have been represented by
varying sized triangles, indicating the incorporation of
microcapsules on the surface and within the yarn 76.
[0052] The excess liquid from the jets 474, 476 passes out the end
of the device at the outlet end of the device 470. This excess is
collected in a tank or container 480 and re-circulated back to the
liquid nozzles 473, 475 in a manner as represented in FIG. 3. In a
preferred embodiment, of the device 470 is enclosed in a casing,
which is designed to collect the excess liquid from the jet 474,
476 and may be under a slight negative pressure so that any vapors
can be evacuated from the surroundings and treated.
[0053] Preparation of the Aqueous Suspension of Microcapsules
[0054] Before being deposited an aqueous suspension of the
microcapsules is required. The microcapsules are mixed with various
ingredients to produce an aqueous suspension.
[0055] The microcapsules containing a wide variety of products
encapsulated within an outer shell typically polymeric in nature,
in one embodiment the encapsulated product is a scent of lavender
which contains linolyl acetate. Commonly the outer shell is a type
of polyurethane or similar compound previously described. The
suspension in includes; the microcapsules in aqueous suspension; a
binder; and a softener typically a silicon micro-emulsion.
[0056] The microcapsules, the binder and the softener are added in
a ratio that varies from 35:35:30 to 48:48:4 with a preferred
embodiment being 45:45:10. These mixtures are then dispersed in
aqueous phase in a ratio up to 25 to 30% with a preferred
embodiment being between 15 and 20%.
EXAMPLES
Example 1
[0057] Multifilament (pes) polyester yarn with lavender perfume
microcapsules. Example 1 describes the production of a yarn that
can be used to produce a fabric with a lavender aroma, mainly for
underwear and hosiery.
[0058] The multi-filament polyester yarn with a final decitex of 78
and 72 filaments, is sprayed with a suspension composed of 85%
water, 6.75% of polyurethane binder, 6.75% of concentrated
microcapsule solution and 1.5% of a silicone softener. The
microcapsules used has a mean diameter of 2 microns (.mu.m). The
deposition/application process was conducted on the false twist
texturing machine.
[0059] The speed and other adjustments are standard for a DTY
process with the following exceptions: the speed differential
between the roll 60, and the rolls 80 of the spraying jet 70. These
speeds were adjusted in order to have minimal tension on the yarn
62 and to facilitate the opening of the multifilament. This opening
of the multifilament produces a yarn which has the microcapsules
within the yarn. The speed of the nip rolls 100 is increased to
provide more tension on the yarn in order to prevent yarn sticking
on the "2 bis" roll, 80. The stickiness of the yarns derives from
the fresh solution being sprayed thereon. The delivery rate of the
liquid to the jet 70 is 0.139 ml/min and the air pressure is 20
psi.
[0060] The yarn produced in Example 1 was knitted on a "FAK" (Fiber
analysis knitter) one feed laboratory knitting machine (Lawson
Hemphill Inc.) with a E22 gauge.
Example 2
[0061] Multifilament polyamide (nylon) yarn with citronella (lemon
grass) perfume microcapsules.
[0062] The multi-filament nylon yarn with a final decitex of 78 and
68 filaments was sprayed with a suspension composed of 85% water,
4.5% of polyurethane binder, 9% of concentrated microcapsule
solution and 1.5% of a silicone softener. The microcapsules once
again had a mean diameter of 2 microns (.mu.m). The deposition
process was conducted in the same manner, at the same speed and
settings as described in Example 1. The delivery rate of the liquid
to the jet 70 is 0.439 ml/min and the air pressure is 30 psi. The
deposition of the microcapsules was conducted on a textile winding
machine.
[0063] The yarn produced was knitted and compared statistically as
in Example 1.
Example 3
[0064] Multifilament yarn polypropylene (pp) with lavender perfume
microcapsules.
[0065] The multi-filament pp (polypropylene) yarn with a final
decitex of 78 and 68 filaments was sprayed with the solution
composed of 80% water, 9% of polyurethane binder, 9% of
concentrated microcapsule solution and 2% of a silicone softener.
All components and conditions were maintained as in Examples 1 and
2. The delivery rate of the liquid to the jet 70 is 0.781 ml/min
and the air pressure is 30 psi.
[0066] The yarns produced in Example 3 were knitted in the same
manner as in Examples 1 and 2.
Examples 4 and 5
[0067] Multifilament Polyamide (nylon) yarn with lavender perfume
microcapsules.
[0068] These Examples were prepared with multi-filament polyamide
(nylon) yarn with a final decitex of 78 and 68 filaments and knit,
as in the preceding Examples.
[0069] Example 4) used a solution composed of 85% water, 4.5% of
acrylic copolymer binder, 9% of concentrated microcapsule solution
and 1.5% of a silicone softener and delivery rate of the liquid to
the jet 70 was 0.439 ml/min and the air pressure is 30 psi.
[0070] In Example 5) a solution composed of 80% water, 9% of
polyurethane binder, 9% of concentrated microcapsule solution and
2% of a silicone softener was used, at feed rate of the liquid to
the jet 70 of 0.781 ml/min and at an air pressure of 30 psi.
Example 6
[0071] A multifilament polyester (pes) yarn with a final decitex of
156 and 200 filaments was used, and sprayed with the solution
composed of 60% water, 18% of polyurethane binder, 18% of
concentrated microcapsule solution and 4% of a silicone softener.
All the process conditions were maintained as in the preceding
Examples. The delivery rate of the liquid to the jet 70 is 2.49
ml/min and the air pressure is 30 psi. The produced yarn was knit
as in the previous Examples.
[0072] The Examples indicate that the method of deposition is
effective on a variety of filaments of different materials and
decitex (fineness of the yarn), through a range of deposition
parameters. All five examples showed good deposition of
microcapsules.
[0073] The embodiments of the invention described above are
intended to be exemplary only. The scope of the invention is
therefore intended to be limited solely by the scope of the
appended claims.
* * * * *