Note: Descriptions are shown in the official language in which they were submitted.
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TITLE
ORGANIC FIBERS AND TEXTILE PRODUCTS
Field of the Invention
The present invention relates to an organic fiber having water repellence
and oil repellence, to a textile product comprising the fiber, and to a method
for
producing the fiber and textile product.
Back~-~ound of the Invention
It is regarded as desirable for textile products to prevent not only
hydrophilic stains, but also lipophilic stains. Hydrophilic stains can be
prevented
to by means of water repellence, and lipophilic stains can be prevented by
means of
oil repellence. Hence, techniques for conferring fibers or textile products
with
water and oil repellency have been investigated and, for some applications,
have
already been put to practical use. A number of methods are used for conferring
fibers or textile products with stainproofing capabilities arising from such
water
15 and oil repelling properties. For example, finishes or coating agents may
be used.
That is, the fiber or textile product is immersed in an emulsion or solution
of a
silicone polymer, fluorocarbon polymer, polyurethane polymer, vinyl polymer or
a copolymer of any of the above, or a spray containing ingredients such as the
above polymers is applied to the fiber or the textile product, following which
2o drying is carried out so as to form a film on the surface of the fibers.
Another
method in current use involves polymerizing monomers or oligomers as
precursors to these polymers on the fiber surface so as to form a film.
However, while covering the entire surface of the textile product with the
above-described film by one of these methods does indeed impart the fibers
with
25 stainproofmg properties, such an approach has resulted in a considerable
loss in
the inherent hand of the fibers. A coating of the above type makes it
particularly
difficult to satisfy requirements for breathability and moisture permeability.
While it is also possible to individually coat each fiber or fiber bundle
making up
the textile product, when a polymer dispersion is used, a film of smaller
thickness
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than the size of the particles in the dispersion cannot be formed. In most
cases,
the film has a thickness of at least several tens of microns, and also laclcs
adequate
strength.
As a result, when the fibers are individually coated with such a coating
agent, the coat has a certain thickness, which compromises the hand of the
fibers
and the textile product. There also exists a thin film-forming method which
uses a
liquid-type coating, and subjects a polymer precursor on the fiber surface to
polymerization and solidification. Unfortunately, it is difficult to obtain a
thin
film of sufficient durability in this way.
l0 Moreover, at the high temperatures which high-strength, high-resistant
organic fibers are expected to withstand, the polymers used for coating in
this way
melt or decompose, and sometimes even ignite. Hence, they lack heat resistance
and flame resistance, and are thus ill-suited for applications requiring heat
resistance and flame resistance, such as firefighting apparel. Accordingly,
there is
15 a desire for fibers, and textile products made thereof, which are endowed
with
excellent heat resistance and durability with no loss of hand, and which have
an
excellent stainproofmg performance.
Such textile products can be woven products, knit products or nonwoven
fabric. Preferred applications include firefighting apparel, gloves and woven
2o fabric for protective clothing.
Summar~of the Invention
A composition is provided which comprises an organic fiber comprising a
thin film which comprises a fluorocarbon silane.
Also provided is a textile product comprising an organic fiber comprising
25 a thin film which comprises a fluorocarbon silane.
Further provided is a process that can be used for manufacturing a high-
strength, heat-resistant fiber or textile product which comprises contacting a
fiber
or textile product with an aqueous emulsion comprising, or produced by
combining, (1) a fluorocarbon silane or its hydrolyzate and (2) optionally a
3o surfactant, an alkoxysilane compound, catalyst, or combinations or two or
more
2
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thereof to produce a fiber or textile-containing mixture and optionally
heating the
mixture.
Detailed Description of the Invention
Any organic fibers of high-strength, heat-resistance can be used.
Preferably the fiber can be coated with a thin film comprising a fluorocarbon
silane or a thin film comprising a copolycondensate of a fluorocarbon silane
with
an allcoxysilane. Preferably, a suitable fiber has a strength of about 10 g/D
to
about 50 g/D, preferably 15 g/D to SOg/D, and a pyrolysis temperature of at
least
about 300°C, and preferably at least 350°C. Examples of
preferred high-strength,
to heat-resistant organc fibers include wholly aromatic polyamide fibers,
wholly
aromatic polyester fibers and heterocyclic aromatic fibers, and mixture of two
or
more fibers.
Suitable wholly aromatic polyamide fibers may be any lcnown aromatic
polyamide fibers. Wholly aromatic polyamide fibers are also known as aramid
fibers,' which are broadly categorized as pare-aramid fibers or mete-aramid
fibers.
Such aramid fibers may be produced and used by any methods known to one
skilled in the art. Pare-aramid fibers may be any lcnown pare-axamid fiber.
Illustrative examples of such pare-aramid fibers include, but are not limited
to,
commercial products such as polyp-phenylene terephthalamide) fibers (produced
2o by E. I. du Pont de Nemours and Company and Du Pont-Toray Co., Ltd. with
the
trademark KEVLAR°), p-phenylene terephthalamide/p-phenylene 3,4'-
diphenylene ether terephthalamide copolymer fibers (produced by Teijin Ltd.
under the trade name TECHNORA), or combinations of two or more thereof.
Mete-aramid fibers may be any known mete-aramid fibers. Illustrative examples
of such mete-aramid fibers include, but are not limited to, commercial
products
such as poly(m-phenylene terephthalamide) fibers (produced by E. I. du Pont de
Nemours and Company under the trademark NOMEX°).
Suitable wholly aromatic polyester fibers may be any known aromatic
polyester fibers. Illustrative examples of such wholly aromatic polyester
fibers
3o include, but are not limited to, self condensed polymers of p-
hydroxybenzoic
acid, polyesters comprising repeat units derived from terephthalic acid and a
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glycol, polyesters comprising repeat units derived from terephthalic acid and
hydroquinone, polyester fibers comprising repeat units derived from p-
hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, or combinations of two or
more thereof. Such wholly axomatic polyester fibers may be produced and used
by any methods known to one slcilled in the art. For example, suitable wholly
aromatic polyester fibers include such commercial products made by Kuraxay
Co.,
Ltd. under the trade name designation VECTRAN.
Heterocyclic aromatic fibers used in the invention may be any fibers
lcnown to one skilled in the art. Illustrative examples of such heterocyclic
to aromatic fibers include, but are not limited to, polyp-phenylene
benzobisthiazole)
fibers, polyp-phenylene benzobisoxazole) fibers (PBO), polybenzimidazole
fibers, or combinations of two or more thereof. Such heterocyclic aromatic
fibers
may be produced and used by any methods known to one skilled in the art. For
example, heterocyclic aromatic fibers include commercial PBO fibers such as
15 those made by Toyobo Co., Ltd. under the trade name designation ZYLON.
The prefeiTed high-strength, heat-resistant organic fibers are aramid fibers
made of a para-type homopolymer which are known to one skilled in the art as
KEVLAR° or TWARON (made by Teijin Ltd.) for their stability to
dimensional
change at elevated temperatures such as, for example, peeling of the thin
film, for
2o their heat resistance, and for their relatively low cost and good
versatility.
Preferably, the thin film has a thickness of about 1,000 nm or lower and a
strength
of 10 to 50 g/D. Also preferred is one or more selected from the group
consisting
of wholly aromatic polyamide fibers, wholly aromatic polyester fibers,
heterocyclic aromatic fibers, and combinations of two or more thereof. p-
25 Phenylene terephthalamide fibers are especially preferred.
The textile products comprise fibers comprising, or coated thereon with a
thin film, which comprises or is produced from a fluorocarbon silane or its
hydrolyzate, or a copolycondensate of a fluorocarbon silane with an
allcoxysilane.
Illustrative examples of suitable textile products include, but are not
limited to,
3o products obtained by the processing of fibers, such as yarn, batting, woven
goods,
knit goods, a broad range of nonwoven fabrics, including felt and paper, as
well as
roving and cord, and combinations of two or more thereof. The textile products
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can also include finished goods which are products obtained by these products
alone, in combinations thereof, or in combination with other materials, such
as
resins or metals. The textile products are preferably woven goods, lcnit goods
or
nonwoven fabrics. Fire-fighting apparel, gloves and woven fabric for
protective
clothing are especially preferred.
The high-strength, heat-resistant organic fibers or textile products
comprising, or coated thereon with (that is, having a thin film formed on the
surface), a thin film of a copolycondensate of a fluorocarbon silane with an
alkoxysilane can be produced by treating the organic fibers or the textile
products
to with an aqueous emulsion comprising (1) a fluorocarbon silane hydrolyzate
or
hydrolyzate thereof, (2) water and optionally (3) a surfactant, an
allcoxysilane
compound, and a catalyst to produce a fiber- or textile-containing mixture
followed by optionally heating the mixture.
The aqueous emulsion can be produced using a fluorocarbon silane and,
15 optionally, a surfactant, a catalyst and an allcoxysilane. It is preferably
carried out
by dispersing a fluorocarbon silane and an amount of surfactant corresponding
to
0.01 to 10, preferably 0.1 to 1 part by weight per part by weight of the
overall
fluorocarbon silane in water such as to make the fluorocarbon silane content,
based on the total weight of the emulsion, from about 0.1 to about 20 wt %,
and
2o preferably from 1 to 10 wt %. An acid or.allcali catalyst can be added in a
catalytic amount (i.e., about 1 to about 1000 ppm final concentration of the
emulsion) to the resulting aqueous dispersion, following which an
allcoxysilane
can be added in an amount corresponding to a mole fraction of 0.1 to 10, and
preferably 0.4 to 0.6, based on the fluorocarbon silane to produce a mixture.
The
25 mixture of the ingredients can be gently mixed. To obtain a uniform and
strong
thin film having a thickness of 1,000 nm or less, preferably 500 or less, more
preferably 100 mn or less, and even more preferably 50 nm or less, it is
preferable
to suppress as much as possible the self condensation reaction by the
fluorocarbon
silane and/or the allcoxysilane. For this purpose, it is preferable to
thoroughly stir
3o the mixture, and to avoid overly rapid addition of the fluorocarbon silane
and the
allcoxysilane.
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The fluorocarbon silane is preferably at least one type of hydrolyzable
fluorocarbon silane having the formula Rr-(CH2)p Si{-(O-CHaCH2)"-ORl}3. In
the formula, Rf is a C3_l8 perfluoroallcyl group or a mixture of such groups;
the
plurality of Rl groups can be the same or different and are independently one
or
more C1_3 alkyl groups; p is 2 to 4; and n is 2 to 10. Rf is preferably a
mixture of
perfluoroallcyl groups having an average of 8 to 12 carbon atoms; Rl
represents
methyl groups; p is 2; and n is from 2 to 4, preferably 2 to 3. More
specifically,
when n is 2, a perfluoroalkylethyltris(2-(2-methoxyethoxy)ethoxy)silane is
especially preferred. When the letter n is 3, a (2-(2-(2-
to methoxyethoxy)ethoxy)ethoxy)silane is especially preferred. This type of
fluorocarbon silane can be produced by any methods known to one slcilled in
the
art. Two or more fluorocarbon silanes can also be used.
Exemplary alkoxysilanes include organosilicon compounds having at least
two alkoxy groups on the molecule, and partial condensation products thereof.
Illustrative examples include (1) silicate of the formula Si(R)4 wherein R is
one or
more group selected from among OCH3, OCH2CH3 and (OCH2CH2)mOCH3 (m
being from 1 to 10); and (2) organoalkoxysilanes of the formula Ra"Sl(QR3)4_9
wherein R~' is one or more C1_lo alkyls; the plurality of R3 groups are the
same or
different and independently one or more C1_3 alkyls; and q is from 1 to 3).
The
2o alkyl group R2 may be substituted with suitable substituents, such as amino
groups, epoxy groups, vinyl groups, methacryloxy groups, thiol groups, urea
groups or mercapto groups. Specific examples of suitable alkoxysilanes
include,
but are not limited to, dimethyldimethoxysilane, methyltrimethoxysilane, 3-
aminopropyltriethoxysilane, N-(2-aminoethyl)-3-
aminopropylmethyldiethoxysilane and 3-glycidoxypropyltrimethoxysilane, and
well as mixtures and partial condensation products of any of the above.
Any acid or an allcalilinic substance may be used as the catalyst. Specific
examples of suitable acids include, but are not limited to, phosphoric acid,
boric
acid, hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid,
and
mixtures of two or more thereof. Specific examples of suitable alkalis
include,
but are not limited to, ammonia, pyridine, sodium hydroxide, potassium
hydroxide, and mixtures of two more thereof. The use of hydrochloric acid or
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phosphoric acid as the catalyst in carrying out the invention is especially
preferred.
Any surfactants that can stabilize the above-described emulsion may be
used. The surfactant generally is a surfactant having an HLB value
sufficiently
high to inhibit self condensation of the fluorocarbon silane hydrolysis
product.
The term "HLB" refers to the HLB system published by ICI America's, Inc.,
Wilmington, Delaware; Adalnson, A.W., "Physical Chemistry of Surfaces", 4~'
edition, John Wily & Sons, New York, 1982). The surfactant can be anionic,
cationic, nonionic, amphoteric, or combinations thereof. The preferred
surfactants
l0 are those with HLB values greater than 5, preferably greater than 12, and
more
preferably greater than 16. Examples of nonionic surfactants include, but are
not
limited to, Rfl-CH2CH2-O-(CH2CH20)11-H, C9H19-C6H4-O-(CHZCH20)SO-H,
other nonionic surfactants, and combinations thereof. Examples of cationic
surfactants include, but are not limited to Rfi-
CHZCH2SCHaCH(OH)CH2N(CH3)3+Cl-, other cationic surfactants, and
combinations thereof. Examples of anionic surfactants include, but are not
limited t0, C12H25(~GH2CH2)4OSO3-NH4+, C12H27-G6H4-S~3Na , Other arilonlC
surfactants, and combinations or two or more thereof. In each of the formulae,
Rfi
is a.perfluoroallcyl group generally having about 3-18 carbon atoms. The
2o preferred surfactants are nonionic surfactants having polyethylene glycol
in the
molecular chain. The use of a nonionic surfactant, such as Rfl-CH2CH2-O-
(CH2CHaO)11-H wherein Rfl is a C3_lg perfluoroallcyl group is preferred.
A variety of additives, including inorganic and organic fillers,
antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, waxes,
colorants
and crystallization promoters, either independently or combinations of a
plurality
thereof may be used.
The emulsion can be used as is or, if necessary, after dilution or other
modification to the desired concentration, by application to the fibers or
textile
products according to the invention using any means known to one slcilled in
the
3o art and most suitable to the processing operation carried out in each case
such as,
for example, impregnation, dipping, coating, or spraying. The emulsion-treated
fibers or textile products can be heat-treated at about 150 to about 500,
preferably
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200 to 450°C, and more preferably at least 250 to 400°C for
about 1 minute to
about 10 hours, thereby bringing to completion not only hydrolysis of the
fluorocarbon silane or hydrolysis of the fluorocarbon silane and hydrolysis of
the
allcoxysilane, but also copolycondensation of the hydrolyzate. A thin film
containing a copolycondensate of a fluorocarbon silane, or its hydrolyzate,
and an
allcoxysilane can be formed. The heat treatment temperature and time period
are
preferably set to the optimal values after talcing into consideration such
factors as
the heat resistance of the target fibers or textile product and the cost
effectiveness
of treatment. The preferred heat treatment temperature or time differs
according
to to the fibers and the textile product. In the case of polyp-phenylene
terephthalamide) fibers, following application of the emulsion, it is
especially
preferable to carry out heat treatment at about 250°C for about 30
minutes. The
ratio of the weight of the copolycondensate coated onto the surface of the
high-
strength fibers, relative to the weight of the high-strength, heat-resistant
organic
fibers, is expressed in the dry state following heat treatment and is referred
to
herein as the "thin film-forming agent piclcu". This value is generally about
0.1 to
10%. Water generally makes up the rest of the emulsion.
The thiclcness of the thin film is a calculated value computed from the thin
filin-forming agent piclcu and based on the assumption that the fiber cross
section,
which is generally approximately circular, is a true circle. For example, if
the thin
film-forming agent piclcu (based on the fiber weight) is 2% and the fabric
weight
is 16.7 g, the weight of the coating layer is 16.7 x 0.02 = 0.334 g. If the
KEVLAR° yarn used in the invention has a density per filament of 1.67
decitex, a
length of 100,000 m, and the fibers in the yarn have a circular cross-section
and a
cross-sectional diameter of 12 ~.m, the entire surface area is about 3.7680
m~'
(37,680 cm2). Assuming that a thin film of the above-described
copolycondensate
having a specific gravity when dry of about 2 g/cm3 is uniformly coated over
this
surface portion, the thin film has a thickness of 44.3 nm.
Before carrying out the above-described emulsion treatment on the fibers
or textile product, if necessary or desired, extraneous substances such as
finish
may be removed from the surface of the fibers by a scouring or solvent
scouring
operation. Moreover, following the completion of thin film heat treatment, an
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operation such as a washing operation to remove residual catalyst and
surfactant
may be carried out by any means lcnown to one skilled in the art such as water
or
solvent extraction. Also, the various above-described additives may be
suitably
added.
In the practice of the present invention, aside from using high-strength,
heat-resistant organic fibers to which has already been applied a thin film of
preferably at most 1,000 nm thickness which comprises primarily a fluorocarbon
silane or its hydrolyzate, and/or a copolycondensate of a fluorocarbon silane
with
an allcoxysilane, the invention can also be treated with the above-described
to copolycondensate textile products such as woven fabric composed of the
above
high-strength heat-resistant organic fibers, protective clothing made of such
woven fabric, or protective gloves manufactured directly from the fibers,
thereby
forming a thin film on the surface of the fibers malting up these textile
products.
Even in cases where formation of the above-described thin film on the fiber
surfaces or the surface of the textile product involves formation of the thin
film on
only a portion of the fiber surface or a portion of the textile product
surface, such
fibers or textiles products shall be regarded as within the scope of the
present
invention.
Examples
2o Examples are given below by way of illustration, although the invention is
not limited by these examples.
The fluorocarbon silane used was a mixture of perfluoroalkyl compounds
having the formula R~(CH2)2-Sid-(O-CH2CHa)2-OCH3}3 wherein Rf is F(CFZ)1~.
The compound in which the letter lc was 6 accounted for 1 to 2 wt % of the
mixture, the compound in which lc was 8 accounted for 62 to 64 wt %, the
compound in which lc was 10 accounted for 23 to 30 wt %, and compounds in
which lc was 12 to 18 accounted for 2 to 6 wt % of the mixture.
The surfactant was a nonionic surfactant of the formula Rf'-CH2CH2-O-
(CH2CH2O)11-H wherein Rf' was a perfluoroallcyl group of 3 to 18 carbons.
3o The organoalkoxysilane was methyltrimethoxysilane (CH3)Si(OCH3)3.
Example 1. Preparation of a Fluorocarbon Silane/Alkoxysilane Emulsion.
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One hundred parts by weight of a fluorocarbon silane and 30 parts by
weight of surfactant were dissolved in water. To the resulting aqueous
emulsion
was slowly added, under stirring by a conventional stirring technique, 2.5 wt
% of
the fluorocarbon silane, based on the overall weight of the emulsion, thereby
suppressing self condensation of the fluorocarbon silane and maintaining it in
a
hydrolyzed state. Next, while measuring the pH of the emulsion with a pH
meter,
phosphoric acid was added and addition was brought to completion when the pH
became 3. Also, methyltrimethoxysilane (CH3)Si(OCH3)3 was added such as to
make the molar fraction of the organoalkoxysilane with respect to the
to fluorocarbon silane 0.45 and stirring was carried out for 4 hours, yielding
a
fluorocarbon silane/allcoxysilane emulsion.
Preparation of the Textile Product.
Three strands of 295 dtex (density per filament, 1.67 decitex), 20s/1 two-
ply yarn spun from polyp-phenylene terephthalamide) staple fiber (made by Du
Pont-Toray Co., Ltd., Tokyo, under the trademark I~EVLAR°) were
paralleled
and fed to an SFG-10 gauge-type glovemaking machine (manufactured by Shima
Seiki Mfg., Ltd., Wakayama Prefecture) and knit into 10-gauge gloves. The
resulting gloves were ordinarily laundered using a commercial neutral
detergent,
and dried. Next, the gloves were immersed in the prepared fluorocarbon
2o silane/allcoxysilane emulsion, then lightly wrung by hand so as to adjust
the
pickup of emulsion non-volatiles to 1 %, based on the weight of the glove.
Assuming that the fiber cross-section was circular, the film thiclcness, as
computed from the thin film-forming agent pickup, was 22 nm. The gloves were
held in a 250°C oven for 30 minutes to effect heat treatment and
curing. The
gloves were then taken out of the oven and cooled to room temperature, after
which they were washed in tepid water and dried. The treated gloves showed no
change in hand or appearance compared with prior to treatment. However, when
the treated gloves were sprayed with water, the drops of water scattered. The
treated gloves demonstrated a striking difference in water repellency compared
3o with untreated gloves.
Example 2. Preparation of Woven Product.
to
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KEVLAR 29° yarn (made by Du Pont-Toray Co., Ltd., Tolcyo) having a
density per filament of 1.67 decitex and composed of 2,000 filaments was used
to
manufacture plain-weave fabric having a warp density of 17.5 ends/25 mm, a
weft
density of 16.~ picles/25 mm, and a basis weight of 444 g/m2. A 5x5 cm square
of
the resulting woven fabric was immersed for 5 minutes in the prepared
fluorocarbon silane/all~oxysilane emulsion, following which it was drawn out
and
wrung free of excess fluid so as to adjust the picl~up of emulsion non-
volatiles,
based on the weight of the fabric square, to 1 %. This woven fabric was held
in a
250°C oven for 30 minutes to effect heat treatment and curing. As in
Example l,
to the film thus obtained had a thiclcness of about 22 nm.
Test Example.
~(1) Water and Oil Repellency
Drops of pure water and hexadecane were deposited in respective amounts
of 2 ~1 onto the surface of the cured fabric obtained in Example 2, and the
contact
15 angle of each fluid was measured with a contact angle meter (manufactured
by
I~yowa Interface Science Co., Ltd., Saitama Prefecture). The test results are
shown in Table 1 below.
In addition, a comparative example was carried out in which drops of pure
water and hexadecane were deposited in respective amounts of 2 ~l onto the
2o surface of woven fabric produced by the method described in Example 2, but
not
treated with the fluorocarbon silane/allcoxysilane emulsion. The contact angle
of
each fluid was measured. The test results are shown in Table 1 below.
Table 1. Water and Oil Repellence
Example Comparative Example
2
Water 124 not measurable due to penetration
of water
Hexadecane109 not measurable due to penetration
of hexadecane
A comparison of the results obtained for woven fabric in Example 2 with
25 the results obtained for the woven fabric in the comparative example showed
that
water and hexadecane penetrated the untreated fabric, mal~ing it impossible to
measure the contact angle. By contrast, in Example 2 in which the test was
n
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carried out on a fabric treated with fluorocarbon silane/allcoxysilane
emulsion, the
fabric exhibited high water and oil repellencies.
~2) Heat Resistance
The treated woven fabric was placed in a 250°C oven and the
contact
angle was measured after the period of time shown in Table 2 had elapsed. The
test results are shown in Table 2.
Table 2. Heat Resistance
Example
2
Initial water contact angle (degrees) 124
Water contact angle after 3 hours at 127
250C (degrees)
Water contact angle after 24 hours at 128
250C (degrees)
The above results showed that, in Example 2, a high water repellency was
maintained even after 24 hours at 250°C.
to (3) Stainproof Properties
One drop of automotive engine oil (engine oil actually used in an
automobile for about 1,000 km) was deposited with a pipette in each of three
places on a treated woven fabric and an untreated woven fabric, following
which
the fabrics were allowed to stand for one hour. Laundry detergent (produced by
15 Kao Corporation, Tolcyo under the trade name ATTACK) was dissolved in
running water to a standard usage concentration of 0.083 wt %. The engine oil-
bearing woven fabrics were placed in the synthetic detergent solution and
agitated
for 5 minutes, then rinsed with running water for 1 minute. Upon comparing the
appearances of both types of sample, the oil stain that penetrated the
untreated
2o product was found not to have disappeared but the oil stain in the treated
product
had disappeared completely. Moreover, sufficient water repellency was
maintained in the laundered fabric.
The above results show that the present invention provides high-strength,
heat-resistant organic fibers endowed with excellent heat resistance and
durability
25 and also an excellent stainproofing performance with no loss of hand. By
using
such fibers according to the invention, there can be obtained textile products
such
12
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as firefighting apparel or gloves which, in addition to having excellent cut
resistance, flame resistance and dimensional stability at high temperatures,
are
coated on the fiber surfaces with a water and oil-repelling thin film. Such
textile
products are resistant to staining and easy to clean. Moreover, because the
thin
film has a very small thickness, textile products can be obtained in which the
characteristics inherent to the constituent fibers, such as their hand, are
essentially
retained with little or no loss. Furthermore, the invention provides a method
capable of manufacturing the above-described fibers and textile products,
which
method readily imparts a high stainproofing performance due to such water and
l0 oil repellency without any loss in the characteristics inherent to high-
strength,
heat-resistant organic fibers, such as the hand.
13
