US3674417A

US3674417A - Process of annealing resin modified textile fabrics

Info

Publication number: US3674417A
Application number: US724223A
Authority: US
Inventors: Wolfgang Karl Ferdinand Otto
Original assignee: Milliken Research Corp
Current assignee: Deering Milliken Research Corp; Milliken Research Corp
Priority date: 1968-04-25
Filing date: 1968-04-25
Publication date: 1972-07-04
Anticipated expiration: 1989-07-04

Abstract

THE FLAT DRY PROPERTIES OF TEXTILE FABRICS CONTAINING SYNTHETIC FIBERS ARE IMPROVED BY MAINTAINING THE FABRIC IN A SMOOTH STATE AT A TEMPERATURE OF AT LEAST ABOUT 80* C. FOR A PERIOD OF AT LEAST ABOUT 1 HOUR. THE PROCESS ALSO IS SUITABLE FOR TREATING FABRICS WHICH HAVE BEEN SUBJECTED TO A TEXTILE RESIN TREATMENT.

Description

United States Patent 3,674,417 PROCESS OF ANNEALING RESIN MODIFIED TEXTILE FABRICS Wolfgang Karl Ferdinand Otto, Spartanburg, S.C., as-

signor to Dgeing Milliken Research Corporation, S artanbur DR) Drawin g Filed Apr. 25, 1968, Ser. No. 724,223 Int. Cl. D06m /58, 15/72 U.S. Cl. 8-115.5 12 Claims ABSTRACT OF THE DISCLOSURE The flat dry properties of textile fabrics containing synthetic fibers are improved by maintaining the fabric in a smooth state at a temperature of at least about 80 C. for a period of at least about 1 hour. The process also 1s suitable for treating fabrics which have been subjected to a textile resin treatment.

BACKGROUND OF THE INVENTION This invention relates to improved textile fabrics containing synthetic fibers, and more particularly, to such fabrics having improved fiat drying properties.

The use of textile fabrics containing synthetic fibers has increased considerably during the past decade, and the textile industry has made important technological advances in the chemical finishing of such fabrics. Numerous processes have been developed for imparting minimum care characteristics to garments and articles prepared from these fabrics. Examples of such advances include the preparation of wash and wear fabrics and durable press fabrics. Considerable effort has been expended in an attempt to find chemical treatments for textile fabrics containing synthetic fibers which will impart to the fabric an ability to resist creasing and to recover its fiat configuration. The ultimate object of such treatments is to obtain a fabric which, on being formed into a garment and being laundered, will have a tendency to return to a predetermined configuration when dried, without ironing. For example, it is often desirable to prepare garments having permanent creases so that the creases are not removed by Washing, and the fabric dries fiat in the areas between the creases. Fabrics capable of resulting in the formation of such fabrics, are referred to as fiat drying, and this term is to be employed in this specification in its broad aspects to include any textile material which normally requires no ironing, pressing or the like for a satisfactory appearance.

Early attempts to prepare fabrics displaying fiat drying qualities involved the utilization of synthetic fibers such as glycol terephthalate fibers either alone or in combination with natural fibers such as cotton.

Heat setting has been widely used in the finishing of fabrics prepared from blends of natural and synthetic fibers, and especially polyester/cotton blends. The heat setting normally is carried out prior to any chemical treatment and involves exposing the fabric to a temperature above 175 C. for about 1 to 1.5 minutes. When higher temperatures are utilized, exposure for shorter periods is customary, e.g., -4O seconds. The treatment results in an increase in fiber density of the synthetic component and improves the fabrics dimensional stability and wrinkle resistance to some degree. However, fabrics treated in this manner exhibit little or no improvement in spin fiat dry performance.

The fiat drying properties of these and other fabrics have been improved by applying resins such as amine formaldehyde resins and urea formaldehyde resins. While "ice these treatments have provided textile fabrics having improved wrinkle resistance and flat drying properties, they often impart to the fabric certain disadvantages which detract from their commercial acceptance. One of the principal difi iculties of the amine or urea type resin treatments is that as the amount of resin placed into the fabric is increased, the abrasion resistance of the fabrics decreases rapidly and the tendency to yellow increases upon being subjected to laundry chlorine bleaches. Although this reaction to bleaching can be reduced to some extent by decreasing the amount of resin in the fabric, there also occurs a lessening in the flat drying properties as the resin is reduced. It becomes necessary, therefore, to critically adjust the amount of resin to balance the fiat drying properties against the effect on abrasion resistance and yellowing on bleaching. Such resin treated fabrics also suffer the disadvantage of a strong tendency to yellow upon ironing or exposure to heat, or simply as a result of repeated washing.

Many other processes have been suggested for improving the flat drying properties of textile fabrics and particularly textile fabrics containing cellulosic fibers. In U.S. Pat. 2,985,501, a process for obtaining flat drying, crease resistant fabrics of blends of cellulosic and synthetic fibers is described. This process involves reaction, while in a swollen condition, of the cellulosic fibers with a crosslinking agent and a strong base, which cross-linking agent includes a chain of at least three carbon atoms such as 1,3-dichloro-2-propanol and 1,2,3,4-diepoxy'butane. Products obtained according to the process of this patent may be bleached repeatedly with chlorine bleaches without injury or discoloration.

Although processes such as those described above do result in textile fabrics having improved fiat drying properties, many of the fabrics or garments prepared from the fabrics display the flat drying properties only when dripdried. That is, upon removal of the fabric or garment from the washing machine prior to the final spin-drying cycle', it is suspended and allowed to dry. The disadvantages of such drip-drying fabrics are quite obvious. The time required for drip-drying is particularly bothersome to the housewife and accounts in part for the limited enthusiasm for such fabrics.

The object of research in this area of fiat drying fabrics in recent years has been to prepare fabrics which resist wrinkling during the spin-drying cycle of an automatic washing machine thereby reducing the time required for drip-drying, and for fabrics which can be tumble-dried in automatic clothes dryers resulting in a fabric without wrinkles. The wet spin dry problem is more acute than the tumble drying problem since the number of wrinkles observed after spin drying is generally of a higher magnitude.

SUMMARY OF THE INVENTION These deficiencies have been overcome by providing a process of treating textile fabrics containing synthetic fibers which comprises maintaining the fabric in a smooth state at a temperature of at least about C. for at least about one hour. It is preferred that the fabric be maintained in a smooth, flat state such as by winding the fabric on a roll while applying sufiicient tension to prevent wrinkling during the winding process. This process is particularly effective with those fabrics containing at least a major proportion of synthetic fibers. The process also is suitable for treating fabrics which have been subjected to a textile resin treatment and will permit a reduction in the amount of resin applied while still yielding acceptable flat dry performance at a reduced abrasion resistance loss. The fabrics treated in accordance with the invention exhibit improved spin and tumble fiat drying properties.

3 DESCRIPTION OF THE PREFERRED EMBODIMENTS The textile fibers useful in the process of the invention are those containing synthetic fibers such as polyester, polyamide and polyacrylonitrile fibers. The fabric may be prepared from these fibers alone or from a blend of such synthetic fibers and cellulosic fibers. The fabric preferably is one containing at least a major proportion of these synthetic fibers.

The polyester fibers are preferably those fibers obtained from high molecular weight products which are obtained by reacting glycols such as ethylene glycol, propylene glycol and the like, with polycarboxylic acids, or esters, such as, for example, terephthalic acid, isophthalic acid, adipic acid, succinic acid and dimethyl terephthalate. A particularly useful polyester is obtained by condensing ethylene glycol and dimethyl terephthalate. These preferred polyesters are chemically available under such trademarks as Dacron, Kodel and Fortrel. Orlon is an example of a commercially available synthetic polyacrylonitrile fiber.

As mentioned above, the textile fabric may be prepared from a blend of one of the above synthetic fibers with a natural fiber such as natural cellulose, regenerated cellulose or modified cellulose fibers having a portion of the hydroxyl groups blocked by ester or ether groups. Examples of the latter materials include yarns or fabrics composed of cellulosic acetate or methyl cellulosic fibers. Examples of blends of fibers include a 65/35 blend of polyester (Dacron) lcotton, a 65/35 blend of Fortrel/ cotton and 55/45 blend of Orlon/rayon.

The fiat dry properties of the textile fabrics containing synthetic fibers as exemplified above are improved by maintaining the fabrics in a smooth state at a temperature of at least about 80 C. for at least about one hour. This process generally is accomplished by winding the fabric on a roll under sufficient tension to prepare a roll of fabric having substantially no wrinkles therein. The Winding can be accomplished either manually or through the use of suitable equipment available in the art.

The rolled fabric is placed in an oven which is then heated to the desired temperature. Alternatively, the oven may be preheated to the desired temperature. Preferably the fabric is heated just prior to winding since it is more diflicult to heat the fabric to the desired temperature on the roll. The rolled fabric is maintained at this temperature for a period of time suflicient to modify the characteristics of the synthetic fibers, e.g., crystallinity, density or crystal reorientation, to provide the desired improvement in the flat dry properties of the fabric. It has been found that there is a relationship between the time and temperature whereby fabrics subjected to higher temperature need not be treated for as long a period. Generally, temperautres of at least 80 C. are utilized and preferably the temperature should be in the range of about 90. to about 130 C. although temperatures as high as 150 C. have been found to be useful.

The limit on the upper temperature is dependent on the fabric and finish on the fabric, and the fabric should not be heated to such a temperature or for so long a period as to cause yellowing and/or degradation to occur. Treatment of the fabrics at these temperatures for as little as one hour is found to improve the properties of the fabric although it is preferred to treat the fabric for at least 3 hours and sometimes as long as 30 hours. Again, the nature of the fabric and any textile resin coatings thereon should be considered in determining the optimum conditions of time and temperature for a particular fabric. Subjecting the fabrics to a temperature of about 90130 C. for a period of 4 to 16 hours generally is found to improve the properties of the fabrics to a desirable level. Under these particular conditions, both spin dry and tumble dry properties are improved.

The tumble dry performance of the fabrics treated in this manner is greatly improved over a similar fabric not subjected to the treatment. The spin dry properties of textile fabrics containing synthetic fibers often are more difficult to improve. It has been found, for example, that the spin dry properties are improved to a greater degree when the fabric has not been heat-set prior to treatment in accordance with the process of the invention, and the improvement in spin dry characteristics is inversely proportional to the degree of heat setting. That is, the improvement in spin dry performance is greater when partially heat-set fabrics are subjected to the process of the invention than when a fully heat-set fabric is treated. Moreover, if the textile fabric is to be Sanforized, the sanforizing step should be carried out before the fabric is rolled-heated in accordance with the invention. Sanforizing after treatment reduces the effect of the invention on spin dry performance.

As mentioned previously, the process of the invention also is applicable to textile fabrics which have been previously treated with a textile resin or other composition. Many of these resins and compositions have been applied to fabrics to improve various properties of the fabrics such as resistance to shrinking, pilling, soiling, and even the fiat dry properties.

The amount of resin on the fabric can range from about 0.5 to about 20% but is generally from about 2 to 6% based on the weight of the fabric. Examples of such resins usually found on fabrics include the commercially available urea-formaldehyde resins, melamineformaldehyde resins, methylol derivatives of cyclic ethylene ureas, triazone derivatives, urons, formalin and formaldehyde derivatives of acrylamide and carbamates. The resin treatment is aflixed to the fabric substrates by conventional catalysts which include amine hydrochlorides and metal salts such as magnesium chloride and zinc nitrate.

The process of the invention is particularly effective when any of the above formaldehyde-containing resins are applied to the fabric with an excess of formaldehyde. Alternatively, the fabrics can be treated with a formalin solution containing from 10 to 15% of a catalyst, and these treated fabrics also exhibit particularly improved fiat drying properties when subsequently treated in accordance with this invention.

Several variations in the process are possible when resin-treated fabrics are to be subjected to the process of this invention:

(a) The fabric can be padded with the resin solution, wound on the roll while wet, and thereafter maintained at the desired temperature for a given period of time. In this variation the curing of the resin occurs while the fabric is on the roll.

(b) A second possibility involves padding the fabric with the resin solutions, drying the fabric to reduce the moisture content, winding the dried fabric on the roll, and thereafter subjecting roll to the desired temperature. In this variation the fabric is Wound on the roll in a dried state, but cured while on the roll.

(0) The fabric can be padded with the resin solution, dried, cured (partially or fully), and thereafter Wound on a roll and heated. This possibility is particularly useful with white fabrics.

(d) Another possible variation involves padding and drying the fabric, curing the resin on the fabric, washing the resin-treated fabric, thereafter winding the fabric on the roll.

All of these process variations produce fabrics having improved spin and tumble dry properties. The choice of a particular process can be made by anyone skilled in the art depending on his particular preference, the par ticular fabric and the particular resin on the fabric.

The following compositions exemplify the types of resin solutions which can be applied as described above pnor to subjecting the fabric to the process of this invention:

Composition A: Parts by weight Product obtained by combination of 2.2 moles of formaldehyde with a mole of acrylamide taining 20% solids available from Sylvan Chemical Co., Inman, S.C.) 1 Syn-Fae 905 (a non-ionic wetting agent obtained by condensation of 9.5 moles of ethylene oxide with a mole of nonyl phenol) 0.3 Water 62.7

Composition -B:

Pennafresh LCR (an ethyl triazone resin available from Sun Chemical Co., 50% solids) 24 Accelerator MX 3 Synalube CIR-7 3 Syn-Soft A-20 1 Syn-Fae 905 0.3 Water 68.7

Composition C:

Aerotex Reactant No. 9 (a melamineuron resin available from American Cyanamid Co., 50% solids) 24 Accelerator MX 6 Synalube CR-7 3 Syn-Soft A-20 1 Syn-Fae 905 0.3 Water 65.7

Composition D:

Stanset C-35 (a methyl carbamate resin available from Standard Chemical Products, 50% solids) 24 Accelerator MX 6- Synalube CR7 3 Syn-Soft A-20 1 Syn-Fae 905 0.3 Water 65.7

Composition E:

Permafresh 183 (a dihydroxy dimethyl ethylene urea supplied by Sun Chemical Corp., 50% solids) 20 Accelerator MX 6 Syn-Soft A-ZO 5 Syn-Fac 905 0.3 Water 68.7

Composition F:

Stanset C-35 20 Accelerator MX 6 Syn-Soft A-20 5 Syn-Fae 905 0.3 Water 68.7

Composition G:

Aerotex Reactant No. 1 20 Accelerator MX Syn-Fae 905 0.3 Synalube CR-7 3 Syn-Soft A- 1 Formalin (37% solution) 37 Water 23.3

6 Composition H:

Mono-methylol acrylamide 17 Accelerator MX 6 Syn-Soft A-25 (a polyethylene emulsion supplied by Sylvan Chemical Co.) 4

Syn-Fae 905 0.3

Water 69.7

Composition I: v

Mono-methylol acrylamide l7 Accelerator MX 6 Syn-Soft A-25 4 Syn-Fae 905 0.3

Water 72.7

Composition I Permafresh 183 20 Accelerator MX 6 Syn-Soft A-25 4 Syn-Fae 905 0.3

Water 69.7

Composition K:

Aerotex Reactant No. (dihydroxy dimethyl ethylene urea, 50% solids from American Cyanamid Co.) 22

Accelerator MX 6 Syn-Soft A-20 1 Synalube CR-7 3 Syn-Fae 905 0.5

Water 67.5

Composition L: Parts by Weight Condensation product of 2.2 moles of formaldehyde with one mole of acrylamide (50% solids) 2.0

Aerotex Accelerator MX 0.6

Syn-Fae 905 0.3

Syn-Soft A-2 0 0.1

Synalube CR-7 4.0

Water 68.5

The flat dry and wrinkle resistance properties of the textile fabrics prepared in accordance with this invention are evaluated by means of AATCC Test Method 88 A- 1964 T entitled Appearance of Fabrics in Wash-and- Wear Items After Home Laundering. This test is designed to evaluate the retention of the original smooth sur face appearance of wash-and-wear fabrics after repeated home laundering. In this test, fabric samples are subjected to a procedure which simulates home laundering practices whereby the samples are subjected to a 10-minute washing cycle in a Kenmore washer employing commercially available detergent in a water temperature of about 49 C. At the end of the final spin cycle, the samples are removed immediately. Those samples identified as Spin Dry samples are attached by two corners to a clothes line and allowed to dry in still air at room temperature. This washing and drying cycle can be repeated as often as desirable.

Those samples identified as Tumble Dry samples are removed from the automatic washer immediately after the final spin cycle, placed in a tumble dryer and dried at a temperature of from about 49 to 71 C. for about 30 minutes or until dry. The samples are removed immediately after the dryer stops. This washing and drying cycle also can be repeated several times as desired.

Prior to evaluating the samples, they are conditioned by hanging by the two corners with the warp in a vertical position in still air for 2 hours at a temperature of 21 i1 C. The fabric samples are then rated by at least two trained observers using either the low-angle or the overhead lighting procedure. In the low angle procedure the fabric sample is placed fiat on a table next to the threedimensional replicas used as standards. These standards are available from the P. J. Edwards Company, Inc., 25 Williams Street, Jamaica Plain, Boston, Mass. The light is located at table height on one side of the samples, and

the fabric is placed so that the base of the pattern of the fabric is toward the observer.

The overhead lighting procedure differs in that an overhead fluorescent light is mounted above a viewing board upon which the fabric samples are mounted for comparison with five photographs used as standards. These photographs may be obtained from AATCC, PO. Box 886, Durham, N.C.

In either procedure, the observer rates the fabric sample to the nearest tenth of a decimal by comparing the samples with the standards. The standard specimens are rated from 1 to 5, 1 representing a fabric with severe wrinkling and representing negligible or no wrinkling of the fabric sample after completion of the washing and drying. Further details of the procedures are contained in the AATCC Technical Manual, Test Methods Physical Properties, 1964 edition, pages 13-102 to B-106.

The following examples illustrate the process of this invention. Unless otherwise indicated, all parts and percentages are by weight.

EXAMPLE 1 A non-heat set, 65% Dacron/35% cotton, white shirting fabric is padded with Composition A to a wet pickup of about 50% based on the weight of the fabric while maintained on a tenter frame. The padded fabric is dried at 121 C. for approximately 48 seconds. A portion of this fabric (a) is then cured by heating at a temperature of 155 C. for 50 seconds wound on a roll under suiiicient tension, to prevent wrinkling, and thereafter maintained at a temperature of 100 C. for 16 hours. The same procedure is followed with a second sample (b) except that the rolled fabrics is maintained at a temperature of 110 C. for 16 hours.

The fabric treated in this manner exhibits improved fiat dry and wrinkle resistance properties as demonstrated by subjecting the treated fabrics to the home laundering test described previously. A control fabric (given all the treatments except the last treatment on the roll) is also subjected to the same test for comparison. The results are summarized in Table 1 below.

TABLE l.FLAT DRY RATVTIHSESI OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Control t 2. 0 4. 0 Example 1(a) 3. 6 4. 6 Example 1 (b) 3. 8 4. 8

EXAMPLE 2 TABLE 2.FLAT DRY RATg gsGlg OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dr;

Fabric:

Control 2. 3 4. 4 Example 2(a) 2. 6 5. 0 Example 200) 3. 1 5. 0

EXAMPLE 3 The procedure of Example 1 is repeated except that the fabric is treated with Composition C. The low angle rating of the treated and washed fabrics are found in Table 3. The control fabric was given all of the treatments except the roll treatment.

TABLE 3.FLAT DRY RATg figg OF FABRICS AFTER ONE EXAMPLE 4 The procedure of Example 1 is repeated except that the fabric is treated with Composition D. The results of the home laundering test on the treated fabrics are reported in Table 4. The control fabric was given all of the treatments except the final roll treatment.

TABLE 4.-FLAT DRY OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Contr 1. 5 4. 0 Example 4(a) 2. 9 4. 6 Example 4(b) c 4. 0 4. 7

EXAMPLE 5 A non-heat set, 65 Fortrel/ 35% cotton, while shirting broad-cloth is padded with Composition E to a wet pickup of about 50% based on the weight of the fabric while maintained on a tenter frame. The padded fabric is dried at a temperature of about C. for approximately 48 seconds. The fabric is cured by heating at temperature of C. for 90 seconds while maintained on the tenter frame. After curing, the fabric is wound on a roll under moderate tension and maintained at a temperature of 12l C. for 16 hours by placing the rolled fabric in a heated enclosure maintained at the desired temperature.

After one Wash at 49 C. in accordance with the home laundering procedure described previously, the fabrics treated in accordance with this example exhibited improved fiat dry and wrinkle resistance properties and demonstrated by the data reported in Table 5.

TABLE 5.-FLAT DRY RATvliligg OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Control 1. 6 4. 2 Example 5 3. 4 4. 7

EXAMPLE 6 The procedure of Example 5 is repeated except that the fabric is treated with Composition F. The control sample was given all of the treatments except the final roll treatment. The results of the home laundering test are reported in Table 6.

TABLE 6.--FLAT DRY OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Control- 1. 7 4. 2 Example 6 3. 3 4. 4

EXAMPLE 7 a roll under moderate tension and maintained at a temperature of 120 C. for 16 hours by placing the rolled fabric in a container maintained at this temperature. A second portion of this cured fabric (b) is wound on a roll and maintained at 100 C. for 16 hours in a similar enclosure.

The fabrics treated in accordance with the above pro cedure, and a control fabric which is given all the treatments except the roll heat treatment, are subjected to the home laundering test described previously. After one wash, the fabric treated in accordance with the process of this example exhibited improved flat dry and wrinkle resistance properties as demonstrated by the data contained in Table 7.

TABLE 7.FLA'I DRY RATvggg OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry EXAMPLE 8 A non-heat set 65% Fortrel/ 35% cotton, white shirting fabric is padded with Composition H to a wet pickup of 50% by weight based on the weight of the fabric while the fabric is maintained on a tenter frame. The padded fabric is dried at a temperature of about 120 C. for 48 seconds. A sample of this fabric is cured by heating in an oven maintained at a temperature of 163 C. for 90 seconds (control). A second sample of the padded and dried fabric is wound on a roll and cured at a temperature of 120 C. for a period of 16 hours while maintained in a carbon dioxide atmosphere.

After one wash of the home laundering test described previously, the fabric prepared in accordance with the procedure of this example whereby the curing is effected on the roll and the rolled fabric is subjected to this temperature for an extended period, exhibited improved fiat dry and wrinkle resistance properties when compared to a similarly treated fabric which was not given the roll treatment. The results are summarized in Table 8.

TABLE 8.FLAT DRY RATVIgHS OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry 2. 6 3. 6 Example 8 3. 3. 9

EXAMPLE 9 The procedure of Example 8 is repeated except that the fabric is padded with Composition I. The results of the home laundering test described previously are as shown in Table 9.

TABLE 9.FLAT DRY RA'IVVIESGESI OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Control 2. 0 3. 2 Example 9 3. 8 3. 9

EXAMPLE 10 TABLE 10.FLAT DRY na'git e s OF FABRICS AFTER ONE Low angle rating Spin dry Tumble dry Fabric:

Control- 2. 9 4. 8 Example 10 4. 1 4. 9

EXAMPLE 11 A 65 polyester/ 35% cotton, white shirting fabric is padded with Composition K to a wet pickup of about 5 0% based on the weight of the fabric while maintained on a tenter frame. The padded fabric is dried at about 120 C. for approximately 48 seconds and thereafter cured by heating at a temperature of 155 C. for 50 seconds. A portion of the cured fabric (a) is wound on a roll under moderate tension and maintained at a temperature of C. for 6 hours. A second portion of the fabric (b) is rolled on a roll and maintained at a temperature of 105 C. for 16 hours.

After this exposure, these fabrics and a control fabric (not given the heat roll treatment) are subjected to the home laundering test described previously for 1, 2 and 5 washings. The flat dry and wrinkle resistance properties of the fabrics (after tumble drying) are recorded in Table 11. The results demonstrate the improved properties of the products of this invention. No shade change was observed in the white fabrics by either visual observation or by the Hunter Color Dilference Readings.

TABLE 11.FLAT DRY RATING OF TUMBLE DRIED FABRICS A 65 Fortrel/35% cotton, non-heat set white shirting fabric is padded with Composition L to a pickup of about 50%- dried by passing between a pair of heated cans (121 C.) at the rate of 10 yards per minute and cured by heating at 155 C. for 70 seconds. A sample of this cured fabric is taken as the control sample. The remaining portion of the cured fabric is wound on a roll which is placed in an enclosure maintained at C. for a period of 16 hours. A sample (a) of this roll-heated fabric is taken for subsequent testing. The remainder of the fabric is washed and Sanforized. The Sanforized fabric (b) and the other two samples of fabrics are subjected to the home laundering test. The wrinkle resistance ratings, taken after one and ten washes, demonstrate the improved results obtained when the fabric is roll-heated in accordance with the invention.

TABLE 12.-FLAT DRY RATINGS OF FABRICS Low angle rating after- 1 1 EXAMPLE 13 A 65% Dacron/35% cotton shirting broadcloth in the prepared state is wound on a roll under moderate tension and maintained at a temperature of 125 C. for one hour. The fabric treated in this manner is found to have a low angle tumble dry rating after one wash of 4.8.

EXAMPLE 14 The procedure of Example 13 is repeated except that the rolled fabric is maintained at 110 C. for one hour. The low angle tumble dry rating after one wash is found to be 4.1.

EXAMPLE 15 tumble dry rating Fabric treatment (hrs.):

alone (control) 2 11111IIIIIIIIIIIIIIIIIIII EXAMPLE 16 Several samples of a 100% Dacron white shirting fabric in the prepared state are wound on rolls under moderate tension. Some of the samples are maintained at 80 C. while others are maintained at 115 and 150 C. The fabrics treated in this manner exhibit improved fiat dry and wrinkle resistance properties as demonstrated by subjecting the treated fabrics to the home laundering test described previously. The results, after one wash, are summarized in Table 14 and compared with control fabrics which were not subjected to the roll treatment.

TABLE 14.FLAT DRY RATINGS Fabric treatment Overhead ratings Tumble Control.

That which is claimed is:

1. A process for improving the flat dry properties of textile fabrics containing synthetic fibers which comprises impregnating said fabric with a textile creaseproofing composition, drying said fabric, curing said fabric, and maintaining said fabric in a smooth state at a temperature of about C. to about C. for a period of about 1 to 30 hours.

2. The process of claim 1 wherein the textile fabric comprises a blend of cellulosic and synthetic polymeric fibers.

3. The process of claim 1 wherein the textile fabric is provided in a non-heat set state.

4. The process of claim 3 wherein the synthetic fibers are polyester fibers.

5. The process of claim 3 wherein the textile fabric comprises a blend of polyester and cellulosic fibers.

6. The process of claim 5 wherein the cellulosic fibers are cotton fibers.

7. The process of claim 4 wherein the polyester fibers are present in at least a major portion.

8. The process of claim 7 wherein the impregnated textile fabric is maintained in a smooth state by winding on a roll and heated at a temperature of about 90 C. to about 130 C. for a period of about 3 to 30 hours.

9. The process of claim 1 wherein the textile creaseproofing composition is a free formaldehyde containing aminoplast resin.

10. The process of claim 1 wherein the textile creaseproofing composition is a methylolated carbamate.

11. The process of claim 1 wherein the textile creaseproofing composition contains a methylol acrylamide.

12. The process of claim 11 wherein the textile creaseproofing composition contains an acid-acting catalyst and a free radical polymerization initiator.

References Cited UNITED STATES PATENTS 2,952,033 9/ 1960 Goodwin 18-1 2,821,458 1/ 1958 Evans 8-130.1 3,175,875 3/1965 Gagarine 8120 2,985,501 5/1961 Gagarine 8120 3,451,763 6/1969 Weiss 81 15.7 2,499,142 2/ 1950 Helmus 8130.1 3,25 6,25 8 6/1966 Herrman 260-937 GEORGE F. LE SMES, Primary Examiner I. CANNON, Assistant Examiner us. c1. xn.

8-Dig. 4, Dig. 21, 149.2, 130.1, 115.7, 154, 116.3, 116.4, 147, 129; 2876