Soil-resistant textile materials

A textile material suitable for use as an automotive upholstery fabric is provided, which comprises: PA1 (a) a body portion having a face and a back comprised of synthetic, thermoplastic fibers; PA1 (b) said body portion being provided with a substantially oil- and water-repellent fluoropolymer substantially evenly distributed on the face thereof in a minor amount sufficient to improve soil resistance characteristics but less than an amount which would cause said material to burn at a rate in excess of about 2 inches per minute or to support such burning for longer than about one minute; and PA1 (c) said textile material further having been backcoated with a flame-retardant backcoating in an amount sufficient to improve the flammability characteristics of said textile material.

This invention relates to a process for imparting flame resistance 
properties to textile materials and to textile materials produced thereby. 
In one aspect, the invention relates to a process for the application of a 
substantially oil- and water-repellent fluoropolymer to the surface of a 
textile material comprised of synthetic thermoplastic fibers in such a 
manner that the fluoropolymer is very evenly distributed on the surface of 
the textile material. In yet another aspect, the invention relates to a 
fluoropolymer-modified textile material particularly suitable for 
automotive upholstery applications having improved soil resistance and 
flammability characteristics. 
The treatment of textiles with fluorocarbon polymers to impart water- or 
oil-repellency has been known in the art for several years. Generally, 
such treatments are accomplished either by padding a solution of the 
fluorocarbon polymer onto the textile material or by spraying a solution 
of the fluorocarbon onto the material. While such techniques have been 
found to be generally quite satisfactory with regard to the imparting of 
water- and oil-repellency to the textile material, such methods of 
application generally result in a product having substantially reduced, 
and in some cases unacceptable, flammability characteristics. Such 
undesirable characteristics have substantially limited the end uses of the 
thus-treated textile materials. For instance, in the area of automotive 
upholstery applications, the flame-retardance standards which have been 
imposed upon the materials by the U.S. Government have been such that it 
has been thought to be impossible to render the materials oil- and 
water-repellent while at the same time meeting such government standards. 
The development of chemical finishing procedures to impart flame resistance 
to textiles has also become a major concern both to government and 
industry. The establishment of more stringent standards regarding the 
flammability of textiles, and in particular automotive upholstery, has 
substantially limited the ability of the textile industry to provide 
products which not only meet the flammability standards, but which also 
are soil-resistant under the conditions of intended use. 
Therefore, an object of the present invention is to provide a process for 
imparting soil resistance to textile materials such as upholstery fabrics 
and especially automotive upholstery. Another object of the present 
invention is to provide a process for imparting soil resistance to textile 
materials which does not suffer from the aforementioned disadvantages of 
the prior art. Yet another object of the invention is to provide a textile 
material made from synthetic, thermoplastic fibers that is suitable for 
use as an automotive upholstery fabric exhibiting not only excellent soil 
resistance characteristics but which also meets or preferably even exceeds 
all governmentally imposed flammability standards. These and other 
objects, advantages, and features of the present invention will become 
apparent to those skilled in the art from a reading of the following 
detailed disclosure. 
According to the present invention, a textile material suitable for use as 
an automotive upholstery fabric is provided, which comprises: 
(a) a body portion having a face and a back comprised of synthetic, 
thermoplastic fibers; 
(b) said body portion being provided with a substantially oil- and 
water-repellent fluoropolymer substantially evenly distributed on the face 
thereof in a minor amount sufficient to improve soil resistance 
characteristics but less than an amount which would cause said material to 
burn at a rate in excess of about 2 inches per minute or to support such 
burning for longer than about one minute; and 
(c) said textile material further having been backcoated with a 
flame-retardant backcoating in an amount sufficient to improve the 
flammability characteristics of said textile material. 
A process by means of which the textile materials of the present invention 
may be prepared is disclosed in copending prior application Ser. No. 
144,152, filed Apr. 28, 1980 now abandoned, of which the present 
application is a continuation in part. According to that prior 
application, an improved process is provided for imparting soil resistance 
to textile materials made from synthetic thermoplastic fibers, e.g., 
polyester fibers, wherein the flame retardance characteristics of such 
materials are not substantially adversely affected. Broadly described, the 
process for improving the soil resistance characteristics of such textile 
materials comprises applying an effective minor amount, e.g., less than 
about 0.3, preferably less than about 0.25 percent by weight on a solids 
add-on basis of a substantially oil- and water-repellent fluoropolymer to 
the surface of the textile material, drying and curing the resulting 
fluoropolymer-modified textile material. The textile material may be 
treated with an aqueous acid solution to lower the pH of the textile 
material to a pH of less than about 7, generally from about 4.0 to about 
6.5, prior to applying the substantially oil- and water-repellent 
fluoropolymer to the textile material. Further, the back surface of the 
textile material is coated with a flame-retarding composition, e.g., 
backcoated either before, during, or after (but preferably after) the 
application of the fluoropolymer to same. 
A drawing accompanies and is made a part of this disclosure.

A wide variety of synthetic thermoplastic fibers may be used to form the 
body portion of the textile material of the invention. Such materials may 
include, for instance, polyamide fibers, e.g., nylon, especially nylon 6,6 
and nylon 6; polyester fibers; and even acrylic fibers, as well as 
combinations of such fibers with each other. Polyester fibers are, 
however, the preferred thermoplastic fibers. While the invention is 
preferably directed to textile materials made substantially entirely from 
synthetic thermoplastic fibers, it should be understood that minor 
amounts, e.g., up to about 10 percent or even more of one or more natural 
fibers such as cotton or wool, may be provided in the textile material, so 
long as the basic characteristics of the textile material are not 
substantially altered. The textile materials of the invention may include 
woven, knitted, tufted, and nontufted textile materials. As to woven 
textile materials, it may be desirable to surface-finish such fabrics by, 
for instance, napping and shearing them to provide a fabric suitable for 
automotive or other upholstery applications. 
Once the desired textile material substrate has been selected, the soil 
resistance characteristics of such material may be improved according to 
the invention by applying an effective minor amount of a substantially 
oil- and water-repellent fluoropolymer to the textile material to 
substantially cover the fibers of such material in the stratum of fibers 
on and near the surface of the textile material, thereby forming a 
discrete, discontinuous polymer coating on such fibers. Especially 
desirable results can be obtained when the amount of fluoropolymer 
employed is sufficient to provide the desired discrete, discontinuous 
polymer coating on substantially all of the fibers of the textile 
materials at or near the surface of such material. Generally, a discrete, 
discontinuous fluoropolymer coating formed on the fibers on the stratum of 
the fibers on and near the face of the fabric may be provided by applying 
to the textile material less than about 0.3, preferably less than about 
0.25 percent, e.g., less than about 0.2 weight percent of the 
fluoropolymer on a solids add-on basis, based upon the weight of the 
textile material. When less than about 0.01 weight percent is applied 
generally, the soil resistance of the product may be inferior or 
unsatisfactory; and where more than about 0.3 weight percent is applied, 
the flame resistance standards for the textile material product may not be 
achievable. However, when from about 0.1 to about 7.5, preferably about 
0.5 to about 1 weight percent, based on the weight of the textile material 
of a fluoropolymer extender is used in combination with the fluoropolymer, 
the amount of fluoropolymer applied to the textile material may be reduced 
to an amount of less than about 0.15 or even less than about 0.1 weight 
percent without substantially adversely affecting the improved soil 
resistance characteristics of the fluoropolymer-modified textile material. 
According to copending patent applicational Ser. No. 144,152, filed Apr. 
28, 1980, the fluoropolymer is applied by means of an engraved roll 
apparatus. The design and construction of the engraved roll used in the 
process of the invention may assist in achieving a product having the 
desired characteristics. The wall thickness of the roll may vary from 
about 3/4 to about 2 inches. The roll may be dynamically balanced to 
ensure vibration-free operation. In general, the roll may not have a 
run-out greater than about 0.005. The engraved applicator roll consists of 
literally millions of substantially identical microscopic pockets known as 
cells. The surface of the roll may be engraved mechanically with minute 
cells shaped in the form of inverted pyramids, quads, or trihelicals, 
located on the surface at approximately a 45.degree. angle to the axis of 
the roller. The engraved cell structure may be controlled to carry and 
deposit on the fabric substrate a specific volume per square inch area of 
the roll surface. Thus, the exact amount of fluoropolymer to be applied to 
the textile material may be determined. 
In selecting the correct engraving, the objective should be to control the 
volume to levels that will produce the desired end result. Additional 
variables that may affect the volume applied may include viscosity of the 
coating, operating temperature, and percentage of solids in solution. The 
size of the cell may be calculated from the coating requirements and the 
density and solids content of the aqueous fluoropolymer solution to be 
applied. 
As indicated in the attached drawings, the engraved roll apparatus includes 
a bottom roll that is engraved over the face with identical cells and will 
rotate in the fluoropolymer solution carried in a tray. Working on the 
face of the roll is a doctor blade made to oscillate over a short stroke 
in order to make it self-cleaning and leaving only solution in the cells. 
Also, oscillation of the blade may help to achieve even wear of the roll 
face and blade. The greater the number of cells or the greater their 
depth, the more coating will be applied on the fabric. On the textile 
material, the fluoropolymer solution will immediately appear as a series 
of dots close enough to each other to fuse and to give an even film across 
and along the web. 
Once the roll has been engraved, it will continuously produce about the 
same wet thickness of a coating formulation if the doctor blade is working 
efficiently. The coating weight on the roller may, however, be changed 
somewhat by varying the solids content of the fluoropolymer solution. 
Generally, however, with a fluoropolymer solution of a given solids 
content in the tray, the gravure roll will continuously provide the 
required weight of coating on the textile material. 
After the desired amount of fluoropolymer has been applied to the textile 
material, the resulting fluoropolymer-modified textile material may be 
heated to a temperature effective to dry and cure it. The temperature 
required to dry and cure the fluoropolymer-modified textile material, as 
well as the period of time required for such treatment, can vary widely. 
Generally, however, such drying and curing of the polymer-modified textile 
material can readily be achieved by heating the polymer-modified textile 
material to a temperature of from about 200.degree. F. to about 
400.degree. F., preferably about 250.degree. F. to about 250.degree. F., 
for a period of time of from about 10 seconds to about 5 minutes, 
preferably from about 30 seconds to about 2 minutes. 
Once the fluoropolymer-modified textile material has been dried and cured, 
it may be subjected to other processing steps such as brushing, napping, 
shearing, etc., as will be apparent to those skilled in the art. 
Any suitable substantially oil- and water-resistant fluoropolymer may be 
employed in the practice of the present invention. It is believed, 
however, that in order for these fluoropolymers to be suitable, the 
fluorinated chain of the fluoropolymers should be capable of being 
distributed on the fibers of the textile material with proper orientation 
of the perfluoro group to provide an essentially fluorinated surface on 
discrete portions of such fibers. 
The term "polymer" as used herein is to be understood to include adducts of 
two or more of the same or different monomeric units, such as dimers and 
trimers. Usually, the fluoropolymer is linear and may be a homopolymer of 
a fluorine monomer or a copolymer of a fluorinated monomer and a 
fluorine-free organic monomer. Such copolymers are generally random 
copolymers. The fluoropolymers which are useful in the practice of the 
present invention may be prepared from fluorinated organic precursors 
having the perfluoro carbon tail or radical at one end of the molecule and 
a reactive functional group at the other end of the molecule. The 
fluorinated precursor compound described above may then be reacted with 
another compound having functional groups reactable therewith to form the 
adduct or polymer. The fluorine-containing precursor compound may 
alternately be reacted with an ethylenically unsaturated organic compound 
containing a functional group reactable therewith to produce a vinyl 
monomer, such as an acrylate or methacrylate, which acrylate or 
methacrylate is then polymerized by vinyl addition to produce the ultimate 
polymer. Processes for producing such fluoropolymers are known in the art, 
for example, U.S. Pat. No. 2,642,416 and U.S. Pat. No. 2,803,615, the 
disclosures of which are hereby incorporated herein by reference. 
Copolymers may also be prepared by co-reacting the above fluorinated 
monomers with various non-fluorinated ethylenically unsaturated organic 
monomers, including ethylene, vinyl acetate, acrylonitrile, acrylamide, 
styrene, acrylic and methacrylic acid, and alkyl esters thereof. Numerous 
other methods of producing such fluoropolymers are known in the art. 
Fluoropolymers, or liquid admixtures containing same, which are especially 
useful in the practice of the present invention, are commercially 
available from Minnesota Mining and Manufacturing Company, St. Paul, 
Minnesota, under the trademarks "Scotchgard.RTM." and 234, and from E. K. 
duPont de Nemours & Co., Wilmington, Delaware, under the trademarks 
Teflon.RTM. and NPA&G soil and stain repeller products. 
The term "fluoropolymer extender" as used herein is to be understood to 
mean non-fluorine-containing lubricants which serve to enhance the 
application of the fluoropolymer to the textile material and to reduce the 
overall amount of fluoropolymer needed. Any suitable lubricant which is 
compatible with the fluoropolymer and the textile material and which will 
improve the ease of application of the fluoropolymer as well as the amount 
of fluoropolymer required to achieve the desired level of soil resistance 
of the textile material can be employed. Such lubricants may include 
surfactants which may be cationic or non-ionic in character. Typical 
examples of fluoropolymer extenders meeting the above criteria and 
Hydronap 3A-FR, an ethoxylated fatty derivative available from Hydrolabs, 
Inc., of Paterson, New Jersey, and Ampitol PE-30, a 
polyethylene-containing composition available from Dexter Chemical of 
Bronx, New York. 
It has been found that application of a fluoropolymer in the manner 
described above to a textile material, either alone or in combination with 
a fluoropolymer extender, and subsequent curing of resultant 
fluoropolymer-modified textile material substantially improves the soil 
resistance characteristics of such textile materials while in general not 
unduly adversely affecting the flame retardance characteristics of such 
materials. 
The fluoropolymer may, as set forth above, be applied to the textile 
material either by itself or in combination with a fluoropolymer extender. 
As indicated, the fluoropolymer should be applied so that a discrete, 
discontinuous fluoropolymer coating is formed on the fibers on the stratum 
of fibers on and near the surface of the textile material. It has been 
found in this regard when the fluoropolymer is applied as an aqueous 
admixture using, for instance, padding or spraying application techniques, 
that the fluoropolymer is not sufficiently concentrated at or near the 
surface of the fabric where soil resistance is needed, but rather is more 
or less evenly distributed throughout a cross-section of the fabric. 
Therefore, such known techniques may require application of somewhat 
larger amounts of fluoropolymers, which is very costly and such larger 
amounts may tend to adversely affect the flammability characteristics of 
the textile material. It has, therefore, been found that particularly 
desirable results are obtained when the aqueous admixture is applied by 
means of an engraved roll, because the fluoropolymer is very uniformly 
applied to the textile material and the concentration of the fluoropolymer 
at or near the surface of the textile material is maximized. 
In preparing the aqueous admixture containing the desired amount of a 
fluoropolymer emulsion, e.g., from about 0.5 to about 10 weight percent, 
preferably about 1 to 5 percent, the fluoropolymer emulsion which is 
generally a solid fluoropolymer dispersed in a liquid emulsion is admixed 
with a predetermined amount of water to provide the desired concentration 
of the fluoropolymer in the aqueous admixture. One particular method of 
preparing the aqueous fluoropolymer admixture is to admix an effective 
amount of FC-214 "Scotchgard" fluoropolymer emulsion into a predetermined 
amount of water to provide an aqueous admixture containing from about 0.3 
to about 1.5 weight percent of the fluoropolymer. FC-214 "Scotchgard" 
brand fabric protector is a commercially available fluorochemical emulsion 
designed for use on upholstery fabrics and the like for imparting oil- and 
water-repellency, as well as an abrasion-resistant finish to the fabric. 
Such a composition contains as a general formulation the following: 
30% solid-fluoropolymer 
11% methyl isobutyl ketone 
6% ethylene glycol 
53% water 
The above-described fluoropolymer emulsion is stated to have a pH of from 
2.0-3.0, a cationic charge, and a density of 1.125 kg/liter. 
Thus, since the above-described commercially available fluoropolymer 
emulsion contains 30 percent of the fluoropolymer, sufficient water is 
added to the emulsion to provide a resulting liquid admixture containing 
from about 0.1 to about 3 percent of the polymer. 
Another especially suitable commercially available fluoropolymer emulsion 
which can be employed to form the aqueous fluoropolymer admixture for use 
in the process of the present invention is FC-234 "Scotchgard" brand 
fabric protector, a fluorochemical emulsion designed for use on upholstery 
fabrics. Such composition contains as a general formulation the following: 
30% solids (fluoropolymer) 
35% methyl isobutyl ketone 
8% glycol 
35% water 
The above-described fluoropolymer emulsion is stated to have a pH of from 
2.5 to 3.5, a cationic charge, and a density of 1.05 kg/liter. 
The above-described fluoropolymer emulsions, upon dilution with water to 
contain the specified amounts of about 0.1 to about 3 weight percent of 
the fluoropolymer, will thus contain from about 0.10 to about 3.5 weight 
percent of an organic carrier, such as the methyl isobutyl ketone or 
methyl ethyl ketone and from about 0.02 to about 0.8 weight percent of a 
stabilizer, such as glycol or ethylene glycol. 
Other suitable commercially available fluoropolymers and emulsions 
containing same which can be used to form the aqueous fluorocarbon 
admixtures containing from about 10 to about 30 weight percent of the 
fluorocarbon constituent are those fluorocarbon emulsions manufactured and 
sold by E. I. duPont de Nemours and Co., as Teflon.RTM. brand 
fluoropolymer emulsions. 
Any other suitable fluoropolymer, or aqueous emulsion of same, can be 
employed. However, it should be noted that if one is to obtain the desired 
result, the concentration of the fluoropolymer in the resulting aqueous 
admixture should be less than about 10 percent, preferably less than about 
5 percent by weight based on the weight of the aqueous admixture; or, 
where it is used in combination with a fluoropolymer extender, it should 
not be more than about 3 weight percent. Larger amounts than those 
indicated may result in a textile fabric having poor or unacceptable 
flammability characteristics. 
The amount of the fluorocarbon required to be present in the bath will also 
vary depending upon the wet pickup characteristics of the particular 
textile material being treated. For example, the synthetic, thermoplastic 
fiber-containing textile materials which can be treated in accordance with 
the process of the present invention will generally have a wet pickup of 
from about 5 to about 35 percent, more desirably from about 10 to about 30 
percent. 
In an embodiment of the present invention, it has been found that the soil 
resistance characteristics and even the flammability characteristics of 
the textile material may be improved even further by scouring the textile 
material, either prior to or subsequent to backcoating, but prior to 
application of the fluoropolymer, to remove residual processing aids which 
may be present on the textile material, as well as dirt and/or oily 
materials, and to adjust the pH of the textile material to a pH of less 
than about 7, more desirably of from about 4 to about 6.5. By scouring the 
textile material and adjusting the pH of the textile material to less than 
about 7, improved results may be obtained in the subsequent application of 
the fluoropolymer, as well as in other processing which may be performed 
on the textile material. 
The scouring of the textile material to remove any residual textile 
processing aids, dirt, oil residues, and the like can be readily 
accomplished by passing the textile material through an aqueous 
detergent-containing solution heated to a temperature of from about 
100.degree. F. to about 200.degree. F. and thereafter thoroughly rinsing 
the scoured textile material with water to ensure substantially complete 
removal of any residual detergent. Desirably, the rinse water may also be 
heated to a temperature of from about 100.degree. F. to about 200.degree. 
F. 
The amount of the detergent constituent employed in the aqueous 
detergent-containing solution can vary widely as can the type of 
detergent. Generally, however, desirable results can be obtained when the 
amount of detergent constituent employed is from about 0.25 to about 1 
weight percent, based on the total weight of the detergent solution. Any 
suitable detergent can be employed providing the detergent does not react 
with, or cause other deleterious effects, upon the textile material being 
scoured. Typical examples of suitable detergents which can be employed in 
the detergent-scouring of the textile material in accordance with the 
present invention include lauryl alcohol ethyoxylate, alkyl ether 
sulfates, and sulfonates. 
After the textile material has been scoured with the detergent solution and 
thoroughly rinsed, the detergent-scoured material may then be passed 
through an aqueous acidic solution maintained at a temperature of from 
about 100.degree. F. to about 200.degree. F. to adjust the pH of the 
textile material to a pH of less than about 7, generally to a pH of about 
4 to about 6.5. The amount of said acid constituent employed in the 
aqueous acid solution can vary widely, depending to a large extent upon 
the type of acid constituent. As currently envisioned, the passing of the 
detergent-scoured textile material through the aqueous acidic solution 
would be considered as a final step of the scouring of the textile 
material. It should be noted, however, that one could, if the textile 
material was substantially free of textile processing aids, dirt, oil 
residue, and the like, eliminate the detergent scouring step of the 
scouring process and thus the scouring of the textile material would 
consist only of passing the textile material through an aqueous acidic 
solution to adjust the pH of the textile material to the desired pH prior 
to application of the soil polymer to the textile material. It should 
further be noted that the scoured textile material can be dried prior to 
application of the fluoropolymer thereto; or, the fluoropolymer may be 
applied to the wet, scoured textile material. However, it is preferred 
that the fluoropolymer be applied to the wet, scoured textile material. 
Any suitable acid may be employed as the acidic constituent of the acidic 
wash solution provided such acid does not have deleterious effects on the 
textile material being washed, or form a residue which interferes with the 
application of fluoropolymer or the dyeing of the fluoropolymer-modified 
textile material during subsequent processing steps. Illustrative of acids 
which may be employed are acetic acid, formic acid, butyric acid, citric 
acid, oxalic acid, and the like. 
After washing and/or scouring and acid bath treatment of the material, it 
may be subjected to the next processing step, e.g., either backcoating of 
the textile material or application of the fluoropolymer in its wet state, 
or, more desirably, dried by contacting the wet textile material with a 
heat source to substantially dry same prior to application of either the 
flame retardant backcoating or the fluoropolymer. 
It has been found that application of a flame-retardant backcoating to the 
textile material may permit the application of somewhat higher 
concentrations of fluoropolymer to the surface of the material without 
undue adverse effect on flammability, and it may be particularly 
beneficial when the flame retardance characteristics of the final product 
are particularly stringent or where the nature of the textile material is 
such that the applicable standards cannot be met without the application 
of a flame-retardant material. In addition to improvement of the flame 
retardance characteristics of the textile material, the providing of a 
backcoating may also provide other desirable properties in the textile 
material making it particularly suitable for an automotive upholstery 
fabric. Thus the backcoating may serve to improve dimensional stability, 
tensile strength, and abrasion resistance; to minimize seam slippage; and 
to prevent or minimize the textile material from unraveling or cutting. 
Further, the latex backcoating may improve the hand of the material by 
providing the material with body and weight. In addition, backcoating of a 
textile material may also help to prevent or minimize distortion of 
patterns on plush and flat textile materials. 
Application of the backcoating composition to the textile material may be 
accomplished by any suitable means known in the art. Typical of such means 
are the knife-over-roll coater. In such a process, two or three coating 
knife arrangements may be used in tandem or sequentially to deposit and 
smooth the coating while it is still wet and fluid. 
Another suitable method for backcoating the textile material is the use of 
reverse-rotating coating rolls. When employing such equipment, the amount 
of coating to be applied is precisely metered prior to application to the 
fabric by a wiping action. Use of precision-ground and mounted coating 
rolls makes possible control of coating weight to within about 0.002-inch 
thickness. 
The backcoating of the textile material may also be carried out using an 
engraved-roll or rotogravure coating unit. In employing such, the coating 
compound may not be metered prior to application to the textile material. 
The total thickness of coating plus textile material may be metered 
through the gap formed by the reverse smoothing roll and the backing roll. 
Any variation in thickness of the textile material is reflected in 
corresponding thicker or thinner coating at such areas. 
In addition to the wet coating processes, typical ones which have been set 
forth above, one might also employ any of the numerous dry (e.g., 100 
percent solids) coating processes. Typical dry coating processes which are 
well known in the art are the hot-melt coating process and the like. 
While any of the above-similar coating processes may be employed for the 
application of the backcoating composition to the back of the textile 
material, especially desirable results have been obtained when using a wet 
coating process, such as the knife-over-roll coating process. 
A wide variety of elastomer coating compositions may be employed as the 
backcoating composition, so long as they function to improve 
flame-retardance characteristics of the textile material. Typical 
elastomer coating compositions include styrene-butadiene rubber, acrylic 
ester latex compositions, urethane polymers, vinyl acetate polymers, 
polyvinyl chloride polymers, vinylidene chloride polymers, and the like. 
Where the elastomer employed in the backcoating composition is not itself a 
flame-retardant material, or where it is determined to be necessary or 
desirable to further improve the flame resistance characteristics of the 
textile material where the elastomer is itself a flame retardant, the 
elastomer composition may be provided with a separate active 
flame-retardant component. Such active flame-retardant components may 
include, for instance, antimony compounds, e.g., antimony oxide; 
silicates, e.g., aluminum silicates; phosphorous-containing materials, 
especially organic phosphonates; borate salts, e.g., zinc borate; 
aluminum-containing compounds, e.g., alumina hydrate; organic 
halogen-containing compounds, e.g., decabromodiphenyloxide; and other 
well-known flame retardants suitable for use in textile materials. 
Typically, when the backcoating contains an active flame-retardant 
component in addition to the polymeric material such component may be 
present in the backcoating composition in amounts ranging up to about 200, 
preferably about 20 to about 60 parts per 100 parts of latex, based on the 
weight of the backcoating composition (solids basis). 
The amount of backcoating composition employed to backcoat the textile 
materials of the invention may vary widely. Generally, however, such 
coatings will be very lightweight coatings, ranging from about 2 to about 
4 ounces of backcoating composition on a solids basis per square yard of 
textile material. The latex coating compositions employed to backcoat the 
textile materials may contain from about 5 to about 50 weight percent 
solids in order to assure uniform coating of the textile material. Such 
latex coating compositions may be provided with a relatively high 
viscosity (e.g., from about 2000 cps to about 50,000 cps) to avoid 
striking through the textile material. Fillers, e.g., clays or whitings, 
may be used. Normally about 50 to about 300 parts of filler per 100 parts 
of latex may be employed to avoid stiffening of the textile material. 
Typical of such backcoating compositions are aqueous emulsions having the 
following formulations: 
______________________________________ 
TS 
______________________________________ 
FORMULATION I 
Polyvinyl Chloride Polymer 
100 
Decabromodiphenyl Oxide 
30 
Antimony Oxide 14 
Water 125 
FORMULATION II 
Acrylic Polymer 100 
Aluminum Hydrate 53 
Zinc Borate 26 
Zinc Oxide 7 
Fyrol FR-2 (Stauffer) 
79 
______________________________________ 
Numerous other flame-retardant latex coating compositions which are well 
known in the coating art may be used to backcoat the textile material of 
the present invention. 
After the desired amount of the latex coating composition has been applied 
to the back of the textile material, the resulting backcoating textile 
material may be heated to a temperature effective to substantially cure 
the latex coating composition and provide a substantially backcoated 
textile material. The temperature to which the resulting backcoated 
textile material may be heated, as well as the period of time of such 
heating required to cure the latex coating composition and dry the 
resulting textile material, can vary widely, depending to a large extent 
on the amount of latex coating composition applied to the back of the 
textile material, as well as the general type of such composition. 
Generally, however, it has been found that such curing of the latex 
backcoating composition and the drying of the resulting textile material 
may readily be achieved by heating the backcoated textile material to a 
temperature of from about 275.degree. F. to about 375.degree. F. for a 
period of time of from about 30 seconds to about 10 minutes. After the 
textile material has been modified by the application of the 
fluoropolymer, and backcoated, the textile material may be sheared to 
remove uneven hairs from the face of such material and thereby provide a 
more uniform surface. Any suitable shearing process well known in the 
textile art may be employed. 
Various other processing steps may be performed on the textile material of 
the present invention. For instance, the textile material may be dyed by 
any of a variety of suitable methods such as jet dyeing, transfer 
printing, screen printing, and the like. Such dyeing may usually be 
performed prior to the application of the fluoropolymer to the textile 
material. Alternatively, however, the dyeing may be performed after the 
application of the fluoropolymer, especially where a printed color 
decoration on the surface of the textile material is desired or when 
definite repeated forms and colors are employed to form a pattern. Such a 
technique for dyeing a fluoropolymer textile material is disclosed, for 
instance, in U.S. Pat. No. 4,131,744 to Lorence M. Moot (Milliken Research 
Corporation). Especially desirable results may be obtained when the 
fluoropolymer-modified textile material is dyed using a jet dyeing process 
and apparatus such as disclosed in U.S. Pat. Nos. 4,084,615; 4,034,585; 
3,985,006; 4,059,880; 3,937,045; 3,894,413; 3,942,342; 3,939,675; 
3,892,109; 3,942,343; 4,033,154; 3,969,779; 4,019,353; pending U.S. patent 
application U.S. Ser. No. 686,900, filed May 17, 1976, entitled "Printing 
of Pattern Designs with Computer Controlled Pattern Dyeing Device"; and 
U.S. patent application Ser. No. 806,783, filed June 15, 1977, entitled, 
"Apparatus for the Application of Liquids to Moving Materials," each of 
said patents and patent applications being hereby expressly incorporated 
by reference. 
In order to more fully depict the process for improving the soil resistance 
characteristics of textile materials in accordance with the invention, 
reference will now be made to the drawing. The drawing represents 
schematic diagrams of sequential processing steps. However, it is to be 
understood that one could conduct such sequential processing steps as a 
continuous process. 
Referring now to the drawing, and particularly FIG. 1, a supply roll 11 of 
textile material 12 is mounted on a suitable support 14. The advancement 
of material 12 through the backcoating apparatus 16 is indicated by the 
solid line in the direction of the arrows. The textile material 12 is 
continuously withdrawn from roll 11 by power-driven take-up roll 17 and 
passed over a plurality of support rollers such as 18 and 19, idler 
rollers 20 and 21, and brought into contact with backcoating apparatus 16. 
Backcoating apparatus 16 is depicted as having a support roller 22, a 
supply source 24 for supply to the elastomer or latex backcoating 
composition to the back of textile material 12, and a doctor knife 25. 
Doctor knife 25 is adjustably positioned in a spaced relationship with 
support roller 22 and textile material 12 to remove excess latex 
backcoating composition from textile material 12 and also to insure a 
substantially uniform coating of the latex backcoating composition to the 
back of the material. 
After the desired amount of latex backcoating has been applied to the back 
of textile material 12, the backcoated textile material 26 is advanced to 
tenter frame 27 where the material is framed to a desired width. Tenter 
frame 27 extends through curing oven 33 so as to maintain the textile 
material at a desired width during the curing of the latex backcoat. 
Backcoated textile material 26 is passed through curing oven 33 at a 
sufficient rate to insure that the latex coating composition is completely 
dried and cured. Generally, the latex coating composition can be dried and 
cured if the oven is maintained at a temperature of from about 250.degree. 
F. to about 375.degree. F. and the coated textile material is maintained 
in the oven for a period of time of from about 1.5 minutes to about 2 
minutes. The cured latex-coated material 34 is then advanced to take-up 
roll 17, which is mounted on a suitable support 36. 
Referring now to FIG. 2, an apparatus for scouring the cured latex-coated 
textile material produced in FIG. 1 is depicted. Supply roll 17', which 
was take up roll 17 of FIG. 1, contains the cured latex-coated material 
34. Supply roll 17' is mounted on a suitable support 37, and the 
advancement of material 34 through the scouring apparatus is indicated by 
the solid line in the direction of the arrows. Material 34 is withdrawn 
from roll 17 and advanced over a plurality of rollers such as 38, 39, 41, 
42, and 43; through a plurality of scouring vessels such as 44, 46, 47, 
and 48; over a second plurality of rollers such as 49, 51, and 52; through 
nip rollers 53 and 54; through drier means 56; and then to take-up roller 
57, which is mounted on a suitable support 58. Take-up roller 57 may be a 
power-driven take-up roller to insure proper advancement of material 34 
through the scouring vessels and the drying means. 
In the scouring of textile material 34 using the plurality of scouring 
vessels as depicted, one can remove residual textile-processing aids, 
dirt, and oily deposits in the first of the series of scouring vessels and 
adjust the pH of textile material 34 in the 1st of the scouring vessels. 
To be more explicit, scouring vessel 44 contains an aqueous detergent 
solution as hereinbefore set forth; vessel 48 contains an aqueous acidic 
solution as has likewise herebefore been described. Each of the aqueous 
mediums in the scouring vessels is maintained at a temperature of from 
about 100.degree. F. to about 200.degree. F., more typically about 
120.degree. F. Textile material 34 is maintained in a substantially taut 
position as it passes through scouring vessels 44, 46, 47, and 48, by a 
plurality of support rollers such as rollers 59, 61, 62, 63, 64, 66, 67, 
68, 69, 71, 72, 73, 74, and 76. Excess aqueous acidic solution used to 
adjust the pH of the textile material is removed by passing the wet 
material through nip rollers 53 and 54 prior to passing the acid-treated 
material into drier means 56, in which the material is heated to a 
temperature sufficient to substantially dry the textile material. The 
desired pH-adjusted textile material is then advanced to take-up roll 57 
and from there can be stored for subsequent use in the application of the 
fluoropolymer and the process depicted in FIG. 3, or moved directly to 
such process. 
Referring now to FIG. 3, a process and apparatus suitable for applying the 
fluoropolymer to the pH-adjusted, backcoated textile material is set 
forth. Supply roll 57', which was take-up roll 57 of FIG. 2, contains 
pH-adjusted, dried, backcoated textile material 81. Supply roll 57' is 
mounted on a suitable support 82 and the advancement of material 81 
through the engraved roll apparatus is indicated by the solid line in the 
direction of the arrows. The textile material 81 is continuously withdrawn 
from roll 57' by power-driven take-up roll 87 and passed over a plurality 
of support rollers such as 88 and 89, idler rollers 90 and 91, and brought 
into contact with engraved roll apparatus 86. Engraved roll apparatus 86 
is depicted as having a pressure roller 92, a supply reservoir 94 for 
supplying the fluoropolymer composition 95 to the engraved roll mechanism 
96. Doctor knife 97 is adjustably positioned in a spaced relationship with 
engraved roll mechanism 96 to remove excess fluoropolymer composition 95 
from engraved roll 96 so that the amount transferred to textile material 
81 may be adjusted to the desired level. 
After the desired amount of fluoropolymer composition has been applied to 
the textile material, the textile material may be advanced to tenter frame 
97, where the material is framed to a desired width and passed through 
curing oven 103 at a sufficient rate to insure that the fluoropolymer 
applied to the surface of the textile material is completely dried and 
cured. Generally, the composition can be dried and cured if the oven is 
maintained at a temperature of from about 200.degree. F. to about 
400.degree. F. and the textile material is maintained in the oven for a 
period of from about 10 seconds to about 5 minutes. The cured, dried 
textile material 105 is then advanced to take-up roll 87, which is mounted 
on a suitable support 106. Take-up roll 87 is driven by drive means 108. 
FIG. 4 is an enlarged view of engraved roll mechanism 86 shown in FIG. 3. 
The identifying numbers refer to the same parts of the apparatus 
identified in FIG. 4. FIG. 4 more clearly illustrates the function of 
doctor knife 97 to regulate and control the amount of fluoropolymer 
applied to the textile material. The figure further illustrates the 
function of the engraving on the engraved roll to meter the amount of 
fluoropolymer composition applied to the textile material. FIGS. 5 and 6 
illustrate further alternative embodiments and the identifying numerals 
again refer to the same parts of the apparatus identified in FIGS. 3 and 
4. In FIG. 56, guide rolls 110, 112, 114, and 116 serve to pass the fabric 
81 through the engraved roll mechanism in a direction that is other than 
normal to the radius of the engraved roll 96. Such disposition of the 
textile material may serve to regulate the amount of fluoropolymer pickup 
by the textile material by increasing the area of contact between the 
engraved roll 96 and the textile material 81. In FIG. 6, guide rolls 114 
and 116 are disposed below the plane, which is normal to the perpendicular 
radius of the engraved roll so that the textile material 81 has a 
prolonged period of contact with the engraved roll 96. 
The preceding sequences, steps, and processes set forth schematically 
illustrate the most desired method for producing the improved products in 
accordance with the present invention. In order to more fully illustrate 
the concept of the subject invention, the following examples are given. It 
is to be understood, however, that such examples are not to be construed 
as unduly limiting the scope of the invention as set forth in the appended 
claims. 
EXAMPLE 1 
In this Example, 4 trials were run to illustrate the relative flammability 
characteristics and soil resistance characteristics of a knitted, 50 
percent polyester, 50 percent nylon automotive upholstery fabric. Values 
are provided for a control sample (Trial 1), to which no fluorocarbon soil 
resistance finish has been applied, as is presently the practice for 
automotive upholstery fabrics being supplied to the automotive industry. 
In Trials 2 and 3, the fluorocarbon finishes identified in column 2 of 
Table 1 were applied by padding from a pad bath. In Trial 4, the 
fluorocarbon finish was applied by means of an engraved roll. 
As to Trials 2-4, an aqueous solution for application to the fabric was 
prepared containing 30 grams per liter (3.0 percent by weight) of an 
emulsified, cationic fluorochemical as identified in column 2 of Table 1. 
In each instance, an aqueous admixture resulted containing about 0.9 
percent fluoropolymer. In Trials 2 and 3, when the aqueous solution was 
padded onto the textile material, wet pickup of solution on the fabric and 
percent fluorocarbon solids applied to the fabric based on dry fabric 
weight were 60 percent wet pickup, resulting in 0.54 percent of the 
fluoropolymer being applied to the fabric. The samples were cured at 
300.degree. F. for 5 minutes, removed from the oven, and cooled to room 
temperature. In Trial 4, the fluoropolymer set forth in column 2 was 
applied to the surface of a knitted 50 percent polyester, 50 percent nylon 
automotive upholstery fabric (this was the same fabric used in runs 1 
through 3). Application in Trial 4 was by means of the apparatus depicted 
in FIG. 1. Wet pickup of solution on the fabric and percent fluorocarbon 
solids applied to the fabric based on dry fabric weight were 20 percent 
wet pickup resulting in 0.18 percent of the fluoropolymer being applied to 
the fabric. The sample was cured at 300.degree. F. for 5 minutes, removed 
from the oven, and cooled to room temperature. 
All of the samples were then evaluated to determine compliance with the 
United States Government Department of Transportation Motor Vehicle 
Standard Test No. 302, used to determine char length in the warp and fill 
directions, burn time in the warp and fill directions, and burn rate of 
materials used in the occupant compartment of automobiles. According to 
the test, a sample of the fabric was mounted horizontally in a U-shaped 
clamp. The mounted sample was placed in an enclosed cabinet, a Bunsen 
burner was positioned under the open end of the clamp, and the flame was 
adjusted to 1.5 inches in height. The fabric was exposed for 15 seconds to 
the flame from the burner tip, which was placed 0.75 inch from the fabric. 
Then burn time, burn rate, and char length characteristics were determined 
using standards specified in the Standard Test Method. In essence, for a 
fabric sample to pass the test and thus be eligible for use in 
automobiles, a fabric sample must exhibit a burn rate of less than 2.4 
inches per minute. The results are summarized in the Table. 
As the Table indicates, where the sample of the particular base fabrics is 
appied with no soil-resistant finish, it is self-extinguishing and easily 
passes the test. The oil-resistance and spray-rating values for the 
sample, however, are both 0 [oil-resistance and water-resistance 
(spray-rating) values were determined using AATCC Standards 118-1966 and 
22-1967]. These values indicate that the sample has very poor 
soil-resistance characteristics. 
In Trials 2 and 3, it can be seen that the oil-resistance and 
water-resistance values are very much improved to 100 for spray rating and 
5 for oil rating. Generally, oil ratings of about 5 or more are considered 
to be acceptable for automotive upholstery. As to the spray rating which 
measures the water resistance of a fabric--that is the resistance to 
penetration by water--in general such fabrics should resist such 
penetration if they are to resist staining and soiling which may occur in 
automotive upholstery fabrics. It is felt that spray-rating values in 
excess of about 70 should be acceptable for automotive upholstery. While 
the soil-resistance characteristics of the padded samples appear to be 
quite improved over that for the control sample and to, in fact, be 
acceptable for automotive upholstery, unfortunately such padded substrates 
cannot be sold to the automotive industry because they fail the 
flammability test as indicated by a burn rate for Trial 2 of 4.5 in the 
fill direction and a burn rate for Trial 3 of 4.81 in the fill direction. 
In Trial 4, surprisingly at a much lower solids pickup of the 
fluoropolymer, the soil-resistance characteristics are virtually identical 
to that indicated for the fluorocarbon-treated padded samples of Trials 2 
and 3. These values are considered to be very acceptable for a fabric in 
automotive applications. Moreover, however, the fabric in fact passes the 
Horizontal-DOT 302 Test, having a burn rate of only 1.6, which is within 
the acceptable limits, specified by the government, of less than 2.4 
inches per minutes. 
TABLE I 
__________________________________________________________________________ 
Fluorocarbon 
Solids Pick-up 
Warp (W) 
Horizontal-DOT 302 
and Method 
% Based on 
or Char Length 
Burn Time 
Burn Rate 
Spray 
Oil 
Trial 
of Treatment 
Fabric Weight 
Fill (F) 
(In.) (Min.) 
In./Min. 
Rating 
Rating 
__________________________________________________________________________ 
1 Control 0 W SE* 0 0 
F SE 
2 3% FC-214 
0.675 W SE/NBR** 
100 5 
padded F 11.50 2.54 4.5 
(75% WPU)*** 
3 3% FC-234 
0.675 W 6.64 2.92 2.28 100 5 
padded F 10.79 2.24 4.81 
(75% WPU) 
4 3% FC-214 
0.180 W SE 100 5 
Engraved Roll F 2.74 1.73 1.6 
(20% WPU) 
__________________________________________________________________________ 
*S.E.--Self Extinguishing 
**S.E./N.B.R.Self Extinguishing/No Burn Rate 
***Wet Pickup 
EXAMPLE 2 
In this Example, summarized in Table 2, an aqueous solution containing a 
fluorochemical was prepared as set forth in Example 1. In Trial 1, 
flammability characteristics and soil-resistance characteristics are 
provided for a control sample of a knitted 100 percent polyester 
automotive upholstery fabric to which no soil-resistance finish was 
applied. The sample passes the flammability test but has a poor spray 
rating. 
In Trial 2, a separate sample from the same lot of fabric as the control 
sample was padded from a 3 percent aqueous solution of the polymer 
(FC-214) (70 percent wet pickup, 0.63 percent fluoropolymer applied to the 
fabric). As can be seen, the spray rating (water resistance) is much 
improved, but the burn-rate value is very marginal and could not be relied 
upon for a commercial product. 
In Trial 3, the apparatus as set forth in FIG. 4 was employed to apply the 
polymer (20 percent wet pickup, 0.18 percent fluoropolymer applied). As 
can be seen, the spray rating remained at a very high level, even with a 
much lower application rate. Furthermore, the sample did not even ignite 
so that the flammability characteristics are acceptable for automotive 
applications. 
TABLE II 
______________________________________ 
HORIZONTAL- 
DOT 302 
Burn 
Warp (W) Char Burn Rate 
Method of or Length 
Time (In./ Spray 
Trial 
Treatment Fill (F) (In.) (In.) 
Min) Rating 
______________________________________ 
1 Control W 0 0 DNI* 0 
F 0 0 DNI 
2 3% Padded W SE** 80 
F 3.04 1.28 2.4 
3 3% Engraved 
W DNI 80 
Roll F DNI 
______________________________________ 
*D.N.I.--Did Not Ignite 
**S.E.--Self Extinguishing 
EXAMPLE 3 
This Example illustrates the necessity of controlling the amount of 
fluorochemical applied to the textile substrate, even when the method of 
application is by means of an engraved roll in each instance. The results 
are summarized in Table 3. Column 1 in the Table provides an 
identification of the automotive fabric substrate. In Column 2, the 
concentration of fluorochemical (FC-214 in each instance) in the aqueous 
solution is indicated. At 4.5 percent fluorochemical concentration in the 
aqueous solution applied, the wet pickup was 20 percent, resulting in 0.27 
percent of the fluoropolymer being applied to the fabric. At 6.0 percent, 
0.36 percent of the fluoropolymer was applied to the fabric at the same 20 
percent wet pickup. As can be seen from Table 3, the soil-resistance 
characteristics are comparable in most instances and generally acceptable 
for automotive applications. At the higher level of fluorochemical 
application, however, the flammability characteristics are generally less 
acceptable. 
TABLE III 
__________________________________________________________________________ 
Fluorochemical 
Warp (W) 
Horizontal-DOT-302 
Trial and Concentration of 
or Char Length 
Burn Time 
Burn Rate 
Oil Spray 
Fabric Aqueous Solution 
Fill (F) 
(In.) (Min.) 
(In./Min.) 
Rating 
Rating 
__________________________________________________________________________ 
50% nylon 
4.5% W SE 5 90 
50% polyester F 2.0 1.0 2.0 
warp knit 
50% nylon 
6.0% W SE 5 90 
50% polyester F 10.0 3.5 2.9 
warp knit 
100% poly- 
4.5% W SE 0 90 
ester plush F SE 
knit 
100% poly- 
6.0% W SE 0 90 
ester plush F 6.25 3.25 1.9 
knit 
100% poly- 
4.5% W SE 5 90 
ester woven F 10.0 3.1 3.2 
100% poly- 
6.0% W 10.0 3.5 2.9 5 90 
ester woven F 10.0 2.55 3.9 
100% poly- 
4.5% W SE 5 80 
ester warp F 2.25 1.0 2.25 
knit 
100% polyester 
6.0% W SE 5 90 
warp knit F 6.50 2.15 3.0 
__________________________________________________________________________ 
EXAMPLE 4 
This Example illustrates the significance of the application of a 
flame-retardant backcoating to certain samples within the scope of the 
present invention to provide a product having acceptable burn-rate 
characteristics. Trial 1 is a control and, as Table 4 indicates, it has 
acceptable flammability characteristics with no fluorochemical having been 
applied. After application of FC-214 to the fabric, however, from an 
aqueous bath containing 6 percent of the fluorochemical (0.36 percent 
fluorochemical applied at 20 percent wet pickup) as Trial 2 indicated, the 
flammability characteristics were such that the DOT test could not be 
passed, e.g., 2.9 in./min. in the fill direction. After the fabric was 
backcoated, Trial 3, with a Flame Retarder N composition, to a pickup of 
20 percent by weight based on the weight of the fabric, the fabric was 
self-extinguishing, as was the control. Flame Retarder N is an inorganic 
flame-retardant salt sold by Consos, Inc., Charlotte, North Carolina. 
Flame retarder or composition contained 20 percent by weight Flame 
Retardant N, about 40 percent polyvinylidene chloride which functions as a 
binder, with the remainder being fillers. A similar procedure was followed 
in Trials 4 through 10, using different flame-retardant backcoating 
compositions. In Trial 4, according to the invention, the fluorochemical 
was applied by a gravure roll, and the sample was backcoated with the 
indicated flame retardant in the form of a composition wherein the 
remaining components were the same as those employed in Trial 3. A similar 
procedure was followed in Trials 5 through 10, varying the flame-retardant 
material employed. In Table 4, decabromodiphenyloxide is an organic salt 
sold by Aurolux Chemical, Inc., of Hope Valley, Rhode Island. Glotard 
N.T.B. is an organic phosphorus compound made by Glotext Chemical, Inc., 
of Roebuck, South Carolina. Flame Retarder PL is a liquid blend of 
ammonium salts and organic nitrogenous compounds sold by Consos, Inc., of 
Charlotte, North Carolina. 
TABLE IV 
__________________________________________________________________________ 
Method of Warp (W) 
Horizontal-DOT-302 
Treatment or Char Length 
Burn Time 
Burn Rate 
Trial (Engraved Roll) 
Fill (F) 
(In.) (Min.) 
(In./Min.) 
__________________________________________________________________________ 
1-100% poly- 
Control W SE 
ester knit F SE 
2-100% poly- W SE 
ester knit 
6% FC-214 F 4.28 1.75 2.45 
3-100% poly- 
20% Flame W SE 
ester knit 
Retarder N B/C* 
F SE 
4-100% poly- 
20% Flame Retarder 
W 2.46 2.4 1.02 
ester knit 
N, 6% FC-241 
F 2.50 2.0 1.25 
5-100% poly- 
20% DBDPO** B/C* 
W SE 
ester knit F SE 
6-100% poly- 
20% DBDPO** B/C* 
W SE 
ester knit 
6% FC-241 F 2.38 1.5 1.59 
7-100% poly- 
20% Glotard 
W SE 
ester knit 
N.T.B. B/C* 
F SE 
8-100% poly- 
20% Glotard N.T.B. 
W SE 
ester knit 
B/C* 
6% FC-241 F SE 
9-100% poly- 
20% Flame W SE 
ester knit 
Retard PL B/C* 
F SE 
10-100% poly- 
20% Flame Re- 
W SE 
ester knit 
tarder PL B/C 
F SE 
__________________________________________________________________________ 
*B/C--Backcoating Composition 
**Decabromodiphenyloxide Backcoating Composition