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Publication numberUS2400379 A
Publication typeGrant
Publication dateMay 14, 1946
Filing dateSep 15, 1944
Priority dateSep 15, 1944
Publication numberUS 2400379 A, US 2400379A, US-A-2400379, US2400379 A, US2400379A
InventorsRoss C Whitman
Original AssigneeKendall & Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Resin-impregnated woven textile fabric and method of producing the same
US 2400379 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

`Maly 14, 1946. R. c; WHITMAN 2,400,379

RESIN-IMPREGNATED WOVEN TEXTILE FABRIC AND METHOD OF' PRODUCING THE SAME Filed Sept. l5, 1944 Fig. 2.

i@ WM@ IN V EN TOR.

i Patented May 14, 1946 RESIN-IMPREGNATED FABRIC AND METHOD F PRODUCING THESAME WOVEN TEXTILE Ross C. Whitman, Walpole, Mass., assigner to The Kendall Company, Boston,

Mass., a corporation of Massachusetts Application September 15, 1944, Serial No. 554.279

12 Claims.

This invention relates to resin-impregnated woven textile fabrics and methods of making the same, and the object of the invention is to provide improved fabrics of this type having moisture-resistant stiffness and which have substantially no tendency to curl. The principal commercial applications of the invention are found in the field of mechanical or industrial fabrics, particularly fabrics which may be subject to conditions of high humidity and temperature, for example, radio spiders. The fabrics hereof are also useful for condenser and insulating cloths, interlinings, hat materials, shoe linings, and laminated fabrics commonly made from muslins, drills, twills, and sheeting materials.. Resin-impregnated fabrics as heretofore known and used in the art have curled to a substantial extent and the present invention provides a satisfactory and certain basis for substantially eliminating such objectionable 'curling during not only cutting and fabrication into various articles of manufacture (which is sudicient for many purposes) but also during the utilization thereof, for example, fabrics which must retain a certain stiffness even where subject to severe atmospheric conditions of heat and moisture.

The present invention provides novel resinimpregnated fabrics in which undesirable curl is overcome and this latter condition is maintained despite atmospheric changes and provides a ready method of producing such fabrics without lthe use of special equipment and without `substantial increase in manufacturing cost. In accordance with my inventions as more fully described in my co-pendlng applications. Serial Numbers 512,211 and 525,719, filed November 11, 1943, and March 9, 1944, respectively, the factors which inuence fabric curl in stiifened fabrics are yarn size of component yarns as the maior factor and, as other factors, direction and degree of yarn twist, and the number of yarn ends per inch of fabric in the warp and filling directions. Also, as set forth in said applications, the sets of warp and filling yarns have a profound relationship and effect inter se and the fabric curling or torque effect exerted by a given warp yarn can be and is neutralized or offset by the curling effect of a lling yam of the same size and the same twist (same number of turns per inch and same direction of twist), and, further, the curling effect of one set of yarns (warp or filling) can be neutralized by the other set of yarns whether of unidirectional twist or whether including yarns of both directions of twist, and

though said other set also differs from the first set in yarn size, in twist multiple, and in number of yarns per inch of fabric, the did'erence occurring in two or more of the factors. The method of practicing the present invention by incorporating my said discoveries in the manufacture of resin-impregnated moisture-resistant fabrics having substantially no tendency to curl is fully set forth hereinafter.

Study of certain stlifened fabrics. including the resin-impregnated ceilulosif: fabrics of this invention, resulted in the paradoxical discovery that in such fabrics the curl is caused by an increase in the twist (i. e.. a twisting tighter) of the dominant component yarns. these yarns imparting a. net curling effect even though the same set of yarns include stldened yarns of opposite twist. For example. when a foot Square Jpiece of a certain commercial resin-impregnated fabric was laid upon a flat surface, it was observed to curl in that two of the diagonal corners lifted up somewhat from the nat surface and the other two diagonal corners attempted to curl downwardly. IIhe curi here was caused by a twisting tighter of certain component yarns.

By properly applying these discoveries in yarn manufacture and selection. in weave layout and weaving of textile fabrics for resin impregnation, one canproduce a wide range of novel reninimpregnated stiffened moisture-resistant fabrics (with warp and iilllng of the same or opposite directions of twist) which are characterised by a substantial absence of curl even though resinimpregnated and by a moisture resistance such that the fabric retains a high stiffness even when thoroughly wetted.

In the drawing, showing preferred types of fabrics of this invention,

Fig. 1 is an enlarged diagrammatic view illustrating a resin-impregnated square weave fabric of unidirectional twist; and

Fig. 2 is a diagrammatic view illustrating a resin-impregnated fabric wherein one not of yarns is unidirectional and the other set includes yarns of opposite direction of twist.

Referring to the drawing in which like numerals represent like parts, Fig. 1 illustrates a noncurling resin-impregnated fabric of this invention with cellulosic Z-twist warp yarns t of smaller size than the cellulosic filling yarns' I with the latter equal in number of ends but 0f lower degrec (not shown) of unidirectional Z-twist, in which both sets of yarns tend to twist tighter because of their resin-impregnation, the tendency of the warp yarns I to lift the diagonal opposite lower and upper corners of the fabric, as oriented in the drawing, being neutralized by the filling yarns 3 so that the corners all lie fiat and the fabric does not curl.

Fig. 2 shows another example of resin-impregnated non-curling fabric of this invention with cellulosic warp yarns l-Z and I-S of opposing twists, there being nve yarns l-Z for each yarn t-S as shown. These warp yarns are of larger size than the unidirectional Z-twist cellulosic filling yarns 5, with the latter equal in number of ends with the required degree of twist (not shown) in which both sets of yarns tend to twist tighter because of the resin-impregnation, the net tendency of the warp yarns to lift the lower and upper corners being neutralized by the set of fllling yarns so that the corners of the fabric all lie fiat and the fabric does not curl despite the resin-impregnation.

Nearly all woven textile fabrics have as many or more warp yarns than lling yarns so that, from the standpoint of end count, most V(but not all) typical applications of the invention fall in between a square weave fabric. with its equal number of ends per inch of warp and filling yarns, and a fabric with a two-to-one or higher ratio of warp to filling ends per inch, though the invention is also applicable to fabrics wherein the number of lling ends per inch exceeds that of the warp. Also, for similar reasons of economical and practical manufacture on modern spinning and weaving equipment, nearly all fabrics heretofore. particularly industrial fabrics, have larger warp yarns than nlling yarns. For the same reasons, warp twist has been almost invariably higher than filling twist. in the trade, "warp twist is synonymous with high twist, and filling twist is synonymous with low twist.

Ihe foregoing principles of the invention afforded a basis for my derivation of a mathemati cal equation which, as a practical matter, gives a general guide for successful application and -use of the invention in the actual manufacture of the resin-impregnated non-curling fabrics of this invention. The basic equation is as follows:

Ell=

where M is twist multiple, N is yarns number (size), E is end count, and w and l refer to warp and filling, respectively.

In the use of the equation for fabric design and manufacture after the general construction as to end count and yarn size has been determined. the equation is applied first only to warp and filling yarns of unidirectional twist whether the fabric be simply unidirectional or whether it have unidirectional yarns in but one of the two sets of yarns. Ii' the latter type. the equation is applied first to the unidirectional set of yarns (whether such set he filling, as usually preferred. or warp) and to the yarns of the same direction of twist in the other or second set and to solve the equation so as to determine the number of such latter yarns necessary to neutralize the fabric curling tendency of the first set. The remaining yarns of said second set are then divided equally into yarns of each direction of twist (it being assumed that all the yarns of said second set are of the same size and twist multiple). Referring to the fabric of Fig. 2. for example. the equation is rst applied to filling yarns of unidirectional Z-twist and the required number of warp yarns of the desired size of the same direction of twist necessary to neutralize the fabric Vcurling tendency of said filling yarns is determined, here four warps per six fillings. This leaves two warp yarns for each basic unit of this fabric construction, which two warp yarns are then divided into i-S and IZ, all of the warp yarns in this example being of the same size and twist multiple. This gives the square weave fabric as shown in Fig. 2 in which there are six Z-twist filling yarns for six warp yarns made up of ve Z-twist yarns and one S-twist yarn.

Normally, as inthe preferred fabrics of this invention. at least one set of yarns is of unidirecnecessary, and, similarly, important advantages are lost in so doing.

Where each set includes yarns of opposing twist (as well as where but one set does). the basic equation may be applied to give the net fabric curling effect of each set as follows:

[rzvy-lliffiilf where M equals twist multiple, N equals yarns number, E equals end count. w and f refer to warp and nlling respectively. and Z and B refer to the respective directions of twist.

If either set of yarns includes yarns differing from each other in size or twist multiple. it will be necessary to consider each group of similar yarns separately and add together the results thereof to obtain the total net factor for each set. The twist multiple employed in this equation is the same as that employed in the textile art and equals twist turns Der inch of yarn divided by the square root of the yarn number` (cotton system), and for the purpose of the equation, and in the specification and claims, the size of all yarns is expressed on the cotton system. for example, 350 denier rayon yarns are classified approximately as number 15.2; and the expression end count" is to be taken as meaning the number of yarns per inch of fabric in the designated direction. In the application and use of the invention. itis not necessary strictly to adhere to absolute equality as variations from the equality represented by the equation are necessarily encountered in practice, the ultimate test being whether any given fabric embodies the principles and features of the invention as herein described and` claimed.

1n accordance with this invention, there is applied to the original fabric water or solventcarried potentially water-insoluble resin or resinforming materials. Various resins such as phenol formaldehyde, urea formaldehyde, melamine formaldehyde, protein (e. g. casein) formaldeple that the value of filling when measured at 70 to retain y57% of these resin `materials are water-insoluble when applied, or are rendered water-insoluble after application (by usually) the stiffness obtained is not immediately or readily removed when the fabric is washed. The determining factor in the choice of the resin and its method of application is that water must baking 'the impregnated fabric,

be present during the polymerization of the resin and the consequent stiifening of the fabric. This water may be formed as a product of the condensation of the resin or may be present in the liquid impregnating mixture as a solvent or a carrier.

The impregnatlng materials should be applied in sufficient quantity and concentration so that the resultant end product includes 20 to 150% by weight of resin (based on the weight of the fabric) in order to provide the desired moisture-resistant properties. In the preferred practice of this invention, when thoroughly wetted. for example, for l minutes in water at 70 F., the fabric possesses a stiffness of more than 50% of its stiffness at 32% relative humidity at the same temperature. This corresponds with e, piece of fabric 4at van ordinary outdoor temperature, being very dry, as compared with being subject to extremes of humidity or moisture. This is a typical condition encountered vin radio loud speakers, e. g.. at sea or under tropical conditions under which the resin-impregnated fabric membrane :mustV maintain substantially its original degree of stiff- 'ness measured immediately after theresin has been cured or poiymerized. Such stiffness may be conveniently expressed in units of mean exural rigidity (milligram centimeters) as incident to a standard Pierce Plexometer, and thesaine typical fabrics with their weights andstiness are as follows:

example 1 A heavy stii'i'ened fabric used for stamping out the crown and brimof men's summer hats was found to have objectionable curling character-v istics, which not only made the cutting operation dimcult, but also gave the brim an uneven roll. This base fabric had an actual end count of 20.1 x 17.9 with 3%s yarns in the warp and 4's in the filling, the corresponding twist multiples being 4.25 and 3.27. By altering the specications so that the yarn weights were 3.93 in the warp and 3.19 in the filling, and keeping the same end count and filling twist multiple, it was found by solving the equation for the warp twist multi- 4.07 would give a fabric with a warp preponderance of only .003. This fabric when resin-impregnated according to the teaching of curl, and ture.` The average showed exceptional resistance to moisiiexural rigidity of warp and F. and 32% relative humidity was 45,000, when the resin content based on the weight of the fabric was 35%. After soaking the sample in water at the same temperature for iifteen minutes. there was no apparent loss in stiffness.

` Example 2 A. non-curling resin impregnated batiste with an end count of approximately the stillness measured at 70 F. and 32% relative humidity after it hadV been soaked for fifteen minutes in water at 70 F. This fabric had a resincontent of 98% based on the weight of the untreated fabric and the flexural rigidity measured under the initially stated ecn- 88 x 00 was found this application exhibited no tendency t0 ing employed dition was 2300. In setting up the specifications for this fabric so that a non-curling cloth would result, it was found that the method of balancin the previous example could not be used here. The yarn weights in this fabric lare 69.9ls in the warpand 95.32s in the ailing. Substituting these along with the actual end count of 67.6 x 79.3 and the twist multiples of 5.56 in the warp and 5.12 inthe nlling in the formula gives a. filling value of .3136, compared with a warp value of .7298. In order to bring these values close enough to produce a non-curling fabric.the yarn numbers and other values would have to be very considerably changed. Rather than do this, the fabric may yarns in the warp and only Z yarns in the filling. The ratio of B and l yarns in the warp may be found in the following way, the number oi ends per inch of Z twist yarn required in the warp to exactly balance the filling will be found by setting the warp side of the equation equal to the filling valueY which has already been found and solving for E. This is found in this case to be 40.7 ends per inch. subtracting 40.7 from 87.6, the total lwarp count gives 46.9 ends per inch which must .be balanced and therefore equally divided between Example 3 A radio spider which lies fiat may be stamped from a resin impregnated non-curling 64 x 60 fabric. This fabric which has an actual end count of 63.0 x 59.0 with 29.81's yarns in the warp and 29.925 yarns in the filling may be balanced by properly adjusting the twist multiples. If the warp twist multiple is taken as 4.10, the warp value calculates to be 1.431. If the nlling is then given a twist multiple of 4.31. the filling formula value is 1.392 and the warp preponderance is only .039 which is low enough to give a balanced noncurling fabric. A'Ihe flexural rigidity of this fabric when impregnated with a phenol formaldehyde solution so that the resin content based on the weight of the base fabric is is 7.500 measured at F. and 32% relative humidity. After soaking in water in the same test applied in the previous examples, 60% of the stiffness is retained.

- 'Example 4 A 70 x 40 drill suitable for use as a shoe lining may be treated with a resin so that the resin content of the fabric will be 29% based on the weight of the untreated fabric, and the flexural rigidity measured under the usual conditions,

' that is, '10 F. and 32% relative humidity, will be 400. Virtually all of this sti'ness is retained even after the usual soaking treatment. Freedom of this fabric from curl may be assured by setting be balanced by using both S and Z filling value, calculated from the filling specification of 38.9 ends per inch with 15.95s yarns with a twist multiple of 3.59. we find that 23.3 ends of 13.48.*s warp yarns with a twist multiple of 4.55 are needed to balance the filling. Since the desired number of ends per inch in the warp is actually 69.3. the difference must be equally divided between S and Z yarns. A tie-in of one S yarn to two Z yarns in the warp will approximately accomplish this, giving a fabric which has a filling preponderance of .016 and which is therefore essentially non-curling.

Example 5 A heavy 52 x 36 duck, resin-treated to give it a moisture-resistant stiff finish. may be made to lie flat by making it according to the following specifications. The original fabric had an actual end count of 51.6 x 35.8 and calls for the use in the warp of 9.03s yarns with a twist multiple oi 4.01 and in the filling of 11.52s yarns with a twist multiple of 3.46. These values will give a warp figure of 7.359 and a filling value of 3.012 which indicates that the fabric is way out of balance and that the more satisfactory way of making it non-curling requires the use of oppositely twisted yarns in the warp. Using the given filling value and the yarn number and twist multiple of the warp yarns. it is found that 21.1 ends per inch are required to balance the filling. If the rest of the yarns are equally divided between S and Z twist, there will be 36.35 ends per inch of Z twist yarn and 15.25 ends per inch of 8 twist yarn, which is found to correspond quite closely to a ratio of two S twist yarns to ve Z twist yarns. With this warp tie-in. the fabric is found to have a warp preponderance of .142 which is sufficiently small to give a non-curling fabric. The resin treatment accorded this fabric which consisted of the application of enough resin solution so that the resin content of the finished fabric was 60% based on the weight of the untreated cloth, resulted in the fabric exhibiting a flexural rigidity of 365.000 at 70 F. and 32% relative humidity. After soaking in water at 70 F'. for fifteen minutes. this resin-impregnated duck retained 62% of its original stiffness.

Example 6 A non-curling viscose cotton blend (60% viscose and 40% cotton) may be given a moisture; resistant stiff finish by treating it with a melamine formaldehyde resin so that the resin content of the stiffened fabric is 53% based on the weight of the untreated cloth. This fabric has a flexural rigidity of 34,000 when measured at 32% relative humidity and 70 F. and 70% of this stiffness is retained after the fabric has undergone the soaking treatment described in the previous examples. This fabric has an actual end count of 43.9 by 41.5 and has 14.87s yarns in the warp and 12.11's yarns in the filling. It was found that the fabric could be balanced without resorting to the use of oppositely twisted yarns in the warp by suitably adjusting the twist multiples. A twist multiple of 4.47 in the warp and of 3.40 in the filling will give warp and filling values such that the werp preponderance will be .076. Because of this low value, the fabric embodying these specifications will lie fiat.

Example 7 A stliened condenser fabric which is resistant to moisture and which will not curl under any condition may be made by treating a 76 x 72 lawn with a melamine formaldehyde resin so that the resin content is based on the weight of the untreated fabric. The flexural rigidity of this fabric, the specifications for which are given below. is 1,300 when measured under the usual conditions, and only 20% less when measured after the fabric has been soaked in water for fteen minutes at 70 F. In order that the fabric be non-curling. the specifications are set up in accordance with the equation for balanced fabrics. When the end count, yarn numbers, and twist multiples, 75.8 x 71.3; 59.52s, 85.41'5; 4.45, 3.39, respectively, for a standard fabric of this type are substituted in the equation, it is seen the warp value is .5860 and the filling value .1897. This is, of course, far from a non-curling fabric. Because it is desirable to keep essentially the appearance and characteristics of this fabric, however, it seemed advisable to balance this fabric by using alternate S and Z yarns in the warp. By carrying out similar calculations to those used in Example 2, it was discovered that a warp tie-in of one S yarn to every two Z yarns would give a fabric with a warp preponderance of only .005, and consequently a non-curling fabric.

The resins may .be applied to fabrics made of any type of cellulosic or predominantly cellulosic textile fabrics plain or mixed or to plain or mixed yarns including staple or cut staple natural or synthetic cellulosic fibers. or continuous cellulosic filaments (later referred to). Though non-cellulosic synthetic or natural libres or filaments may be included in minor proportions, it must be borne in mind that in none of these non-celluloslc fibres does a water-swell ing and stifl'ening with resultant reversal of curl occur, as in the predominant cellulosic fibres.

The preferred impregnated fabrics of this invention are made from fabrics woven from or including yarns made up of, or which include predominantly cotton or other natural cellulosic fibres such as sisal. rai'nie, hemp or jute, or synthetic celiulosic fibres such as viscose, cuprammonium and other regenerated cellulosic fibres (either cut staple or continuous filament).

Various impregnated fabrics may be made which include a. substantial proportion of yarns in the warp, filling. or both, which are not swollen and stiiiened so as to produce a reverse curl (yarns twisting tighter), in such fabrics the warp and filling each including swollen and stiifened yarns with their reverse fabric curling tendencies offset in general accordance with the foregoing disclosure. In such cases the curling effect of the proportion of yarns not producing` reverse curl may be safely disregarded as not significant in view of their relatively negligible effect upon curling as compared with that of the pronounced and very much greater curling effect of the swollen and stiifened warp and filling yarns producing reverse curl.

In the practice of this invention, it is important to provide warp yarns and filling yarns that are spun with precision from uniform card sliver to definite sizes and twist multiples, and so woven that all areas of the body of the fabric are strictly uniform in construction since it is these factors, and their relation to each other, that are depended upon in arriving at the desired result. Even with the most modern equipment. and with carefully controlled spinningroom humidity. it is well known that considerable variation in the yarn size occurs as spinning proceeds. A spinning machine balanced and adiusted to produce 30s yarns may, after a week or ten days operation, be found to be delivering as fine as 35s or 36s, or as heavy as 27's or 26s, the shift toward lighter yarns usually proceeding faster and further than the shift towards heavier yarns. These variations are usually explained as resulting from humidity changes, temperature changes, stock changes, and machine wear, producing maladjustments.

Standard practice in modern textile mills calls for the analysis of yarns approximately every two weeks, and the readiustment f yarns size prescribed is made usually on the first roving frame. usually called the slubber," or the second roving frame, known as the first intermediate." This measure of control is satisfactory for ordinary fabric manufacture, but since it would permit drifting of yarn size to the extent mentioned above, it is obvious from the equation underlying this invention that it is entirely inadequate for the practice of the invention. Also, any change in yarn size produces a significant change in twist multiple since the spinning-frame delivers a fixed number of turns pr inch to the yarn, rather than a xed twist multiple. In the manufacture of fabrics of this invention, it is recommended that yarn analyses and equipment adjustment as needed be made daily, usually at the second drawing frame rather than on any of the succeeding roving frames. In addition, special care should be taken in the control of spinning-room humidities. etc.

In making use of the equation, actual yarn sizes, as determined by analyses in the spinning-room, and actual twist multiples, as determined by well known formulas involving spinning-frame gears, should be used rather than the "theoretical or "standar-d values. Similarly, actual end counts as reported by the weave room should be used. It is found that usually the slight changes in the end counts occasioned by variations in tension on the loom are not troublesome providing the cloth tension is checked and adjusted daily in the usual way. For fabrics where a substantially complete absence of curl is the requirement, as in radio spiders, it is found that the old style friction let-od on the loom is to be preferred to automatic positive let-of! mechanism, such as the Roper-Diaper" or Bartlett," which permit greater variations in end counts since they control tension with less precision, generally. Also, reasonable care should be taken to avoid any considerable distortion of the woven "neutralizew fabric in subsequent finishing processes. With fairly equal tensions therein so that the end count in the finished fabric is roughly equally higher or equally lower in both the warp and the nlling, however, no trouble need be anticipated on this porting surface, not to exceed 1% inches. The

preferred and most searching test for base ce1- lulosic fabrics of cotton and/or viscose rayon is by first impregnating the fabric in a solution made up ls follows:

Bakelite, 60% methyl alcohol); 4 Methyl alcohol 1 Water a- 5 The pick-up of the solution by the base fabric may, for example, be from to 150% by weight (on the weight of base fabric). The sample is then pressed between two heated metallic surfaces (net total pressure 10 lbs.) at a temperature of approximately C., for sixty seconds, in order to completely polymerize and set the resin, thus forming a product of this invention. The sample is then at once removed and placed without restraint on a horizontal surface, such as a table, and promptly observed. Since this test is so searching, as a practical matter, the fabrics of this invention so made may be regarded as having substantially no tendency to curl if the sample remains substantially extended and no corner thereof rises more than 1 to 1% inches above the supporting horizontal surface upon which it was placed. Fabrics made in accordance with the preferred practice of this invention incorporating therein any of the resins mentioned above are well within the amount mentioned. The impregnating materials hereinbefore referred to as employed in ordinary commercial use will not cause the rise of a corner of a five inch test square more than V2 to 1 inch above the supporting horizontal surface.

Having thus described my invention, what I desire to claim as new is:

l. A textile material adapted for industrial use comprising a resin-impregnated stiffened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including aset of warp yarns and a set of filling yarns. with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, said sets and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the equality represented by the equation ci El ,ci El i/T s Nr z ,f 20% of the original base fabric weight, including a set of Warp yarns and a set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, at least one of said sets including a substantial number of yarns or each direction of twist, said sets and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the equality represented by the equation itrile-fifi= where M equals twist multiple, N equals yarns number, E equals end count, w and f refer to warp and nlling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moisture-resistant stiffness characteristics,

3. A textile material adapted for industrial use comprising a resin-impregnated stiifened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including a set of warp yarns and a set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, both of said sets including a substantial number of yarns of each direction of twist, said sets and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the equality represented by the equation where M equals twist multiple, N equals yarns number, E equals end count, w and f refer to warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moisture-resistant stiffness characteristics.

4. A textile material adapted for industrial use comprising a resin-impregnated stiifened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including a set of warp yarns and a set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, both of said sets having yarns of unidirectional twist. said sets and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the equality represented by the equation where M equals twist multiple, N equals yarns number, E equals end count, w and J* refer to warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moisture-resistant stiffness characteristics.

5. A textile material adapted for industrial use comprising a resin-impregnated stifiened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including a set of warp yarns and a. set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, said set and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the equality represented by the equationY [cree] ,[d

nu s W71 where M equals twist multiple, N equals yarns number, E equals end count, w Aand f refer to warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moistureresistant stiiiness characteristics, said fabric after wetting for l5 minutes in water at 70 F. exhibiting at least two-thirds of its stiness in an atmosphere of 30% relative humidity at 70 F.

6. A textile material adapted for industrial use comprising a resin-impregnated stiifened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight. including a set of warp yarns and a set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric, at least one of said sets including a y substantial number of yarns of each direction M-erlycfsrf] v Nw Nr where M equals twist multiple, N equals yarns number, E equals end count, w and f refer to warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a' neutralized curling tendency and moistureresistant stiffness characteristics, said fabric after wetting for l5 minutes in water at 70 F. exhibiting at least two-thirds of its stiffness in an atmosphere of 30% relative humidity at 70 F. 7. A textile material adapted for industrial use comprising a resin-impregnated stiffened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including a set of warp yarns and a set of filling yarns,

andere with the yarns of both of said sets uniformly dispersed and arranged throughout the body of the fabric. both of said .sets including a substantial number of yarns of each direction of twist, said sets and yarns thereof being so related with respect to twist direction, number and count as to produce substantially the equality represented by the equation i where M equals twist multiple, N equals yarns number, E equals end count, w and f refer to warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moisture-retwist multiple, yarns sistant stiffness characteristics, said fabric afterv Y' wetting for l5 minutes in water at 70 F. exhibiting at least two-thirds of its stiffness in an atmosphere of 30% relative humidity at 70 F.

8. A textile material adapted for industrial use comprising a resin-impregnated stiffened woven fabric having substantially no tendency to curl, composed essentially of sets of twisted cellulosic yarns and a resinous impregnation to at least 20% of the original base fabric weight, including a set A`of warp yarns and a set of filling yarns, with the yarns of both of said sets uniformly dispersed and arranged throughout the body ofthe fabric, both of said sets having yarns of unidirectional twist, said sets and yarns thereof being so related with respect to twist direction, twist multiple, yarns number and count as to produce substantially the quantity represented by the equation where M equals twist multiple, N equals yarns number, E equals end count, 1v and f refer to Warp and filling, respectively, and Z and S refer to right and left-hand twist, respectively, thereby providing an impregnated fabric having a neutralized curling tendency and moistureresistant stiffness characteristics, said fabric after wetting for l5 minutes in water at 70 F. exhibiting at least two-thirds of its stiffness in an atmosphere of 30% relative humidity at 70 F.

9, The method of producing a woven fabric for industrial uses having moisture-resistant stiffness characteristics and substantially no tendency to curl which consists in spinning, selecting, and weaving a set of uniform warp yarns and a set of uniform filling yarns, the warp yarns being so related to the filling yarns with respect to twist direction and multiple, yarn number and count as to produce substantially the equality represented by the equation where M equals twist multiple. N equals yarns number, E equals warp and filling respectively, and Z and S refer to the respective directions of twist, and then impregnating said fabric with a resinous medium amounting to 20 to 150% fabric weight, thereby providing an impregnated fabric having said neutralized curling tendency and moisture-resistant stiffness characteristics.

10. The method of producing a woven fabric for industrial uses having moisture-resistant stiffness characteristics and substantially no tendency to curl, which consists in spinning, selecting, and Weaving a set of uniform warp yarns and a set of uniform filling yarns, at least one of said sets being of unidirectional twist, the warp yarns being so related to the filing yarns with respect to twist direction and multiple, yarn number and count as to produce substantially the equality reprerrr-yur N N/Nw s VNfa z where M equals twist multiple, N equals yarns number, E equals end count, w and f refer warp and filling respectively, and Z and S refer to the respective directions of twist, and then lmpregnating said fabric with a resinous medium amounting to 20 to 150% of the original base fabric weight, thereby providing an impregnated fabric having said neutralized curling tendency and moisture-resistant stiffness characteristics. l1. The method of producing a woven fabric for industrial uses having moisture-resistant stiffness characteristics and substantially no tendency to curl, which consists in spinning, selecting, and weaving a set of uniform Warp yarns and a set of uniform filling yarns, at least one of said sets including a substantial number of yarns of each direction of twist, the warp yarns being so related to the filling yarns with respect to twist direction and multiple, yarn number and count as to produce substantially the equality represented by the equation:

where M equals twist multiple, N equals yarns number, E equals end count, w and f refer to warp and filling respectively, and Z and S refer to the respective directions of twist. and then impregnating said fabric with a. resinous medium amounting to 20 to 150% of the original base fabric weight` thereby providing an impregnated fabric having said neutralized curling tendency and moisture-resistant stiffness characteristics.

l2. The method of producing a woven fabric for industrial uses having moisture-resistant stiffness characteristics and substantially no tendency to curl which consists in spinning, selecting, and weaving a set of uniform warp yarns and a set of uniform filling yarns, both of said sets including a substantial number of yarns of each direction of twist, the warp yarns being so related to the filling yarns with respect to twist direction end count. w and f refer to` of the original base and multiple. yam number and count as to produce substantially the equality represented by the equation:

:lil on N., N (ih-nal@ (Mf-s E' lo Certicate of Correction Patent No. 2,400,379. May 14, 1946.

ROSS C. WHITMAN y certified that errors appear in the printed specification of the above patent requiring correction as follows: Page 6, second column, line 12, claim set read sets; pa e 7, first column, line 39, claim 8, for` quantity read equality;

age 7, second column, lzine 17, claim 10, for filing read filling; page 8, first column, oe 11, claim 12, for that portion of the formula reading :H: read :1s-+I: and that the said Letters Patent should be read with th e same may conform to the record of the case in the Pa Signed and sealed this 10th day It is hereb numbered 5, for

ese corrections therein that tent OHce.

of September, A. D. 1946.

LESLIE FRAZER,

First Assistant Commissioner of Patents.

and multiple. yam number and count as to produce substantially the equality represented by the equation:

:lil on N., N (ih-nal@ (Mf-s E' lo Certicate of Correction Patent No. 2,400,379. May 14, 1946.

ROSS C. WHITMAN y certified that errors appear in the printed specification of the above patent requiring correction as follows: Page 6, second column, line 12, claim set read sets; pa e 7, first column, line 39, claim 8, for` quantity read equality;

age 7, second column, lzine 17, claim 10, for filing read filling; page 8, first column, oe 11, claim 12, for that portion of the formula reading :H: read :1s-+I: and that the said Letters Patent should be read with th e same may conform to the record of the case in the Pa Signed and sealed this 10th day It is hereb numbered 5, for

ese corrections therein that tent OHce.

of September, A. D. 1946.

LESLIE FRAZER,

First Assistant Commissioner of Patents.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3309259 *Oct 29, 1963Mar 14, 1967Patchogue Plymouth CompanyDouble backed carpet
US5044013 *Feb 8, 1990Sep 3, 1991Ackerman Myron HCrease resistant interliner and method of making the same
US6325110 *May 13, 1999Dec 4, 2001Gividi Italia S.P.A.Woven fabric reinforcement to optimize dimensional stability
US7615178 *Sep 21, 2005Nov 10, 2009Saint Gobain Technical Fabrics America, Inc.Fabric reinforcement and cementitious boards faced with same
Classifications
U.S. Classification442/103, 442/60, 28/167, 139/426.0TW
International ClassificationD03D15/00
Cooperative ClassificationD03D2700/0133, D10B2201/06, D10B2201/02, D10B2501/043, D10B2201/24, D10B2401/062, D10B2201/08, D03D15/00, D10B2501/06
European ClassificationD03D15/00