US2923597A - Crease resistant cyanoethyl cotton fabric of retained tensile strength produced by applying a methylol melamine resin - Google Patents

Description

United States Patent CREASE RESISTANT cYANoETHYL COTTON FABRIC or RETAINED TENSILE STRENGTH PRODUCED BY APPLYING A. METHYLOL MELAMINE. RESIN Theodore F. Cooke, Martinsville, N.J., John W. Eastes, Ridley Park, Pa., and LintonA. Fluck, Basking Ridge, N.J., assignors to American Cyanamid Company, New York, N.Y., a corporation of Maine No Drawing. Application March 31, 1955 Serial No. 498,453

1 Claim. (Cl. 8-129) serious disadvantage, namely marked loss in tensile and tear strength. It is a generally accepted theory that the crease and wrinkle resistance results from a. chemical reaction of the resin with the hydroxyl groups of the cellulose molecule so that the long chains of cellulose arecross linked at suitable intervals by a resin bridge. resulting in the increase in wrinkle resistance but also decreasing, the extensibility so thatunder stress the fabric breaks or tears at, a much lower degree of force than is the case with the original cotton which has greater extensibility. In the past the serious disadvantage of lowered tensile. strength and .poor tear resistance has. been endured in order. toobtain. the advantages of creaseand wrinkle resistance, but. the field. of .utility of crease and wrinkle proofed. fabric. has. been. seriously reduced be cause in cases where the fabric needs high degree of tensile strength or tear resistance, the treated fabric is unsuitable. Y

According to the present invention it has been found that cyanoethylated cottonwhich is a recent development and in which the cotton is reacted with acrylonitrile and caustic alkali: so that a portionof the hydroxyl groups are transformed into beta-cyanoethoxy groups can be treated with thermosetting resins in exactly the same manner as cotton fabrics but the resulting fabric although having the same degree of high wrinkle and crease resistance has the advantage of being almost as strong, in some cases actually as strong, as untreated cyanoethylated fabric and shows a markedly improved tear resistance.

It is not known why the cyanoethylated cotton after resin treatment should show such remarkable increase in tensile and tear strength over ordinary resin treated cotton fabric. In fact, as far as the accepted theory is concerned, it is quite incomprehensible because the cyanoethylated cotton which is useful, that is to say, cotton which still retains its cotton structure normally has less than a third of its hydroxyl groups changed into betacyanoethoxy groups. The best cyanoethylated cotton 2,923,597 Patented Feb 2,

ranges from 3.5-5.5 nitrogen, although material as low as around from 3% nitrogen; is still usefui andhighei'. degrees of cyanoethylation up to the point where one of the three hydroxyl groups on the anhydro-glucose unit of the cellulose has reacted can also be employed. In other words, there is an enormous excess of remaining free hydroxyl groups over that required to react with the small amount of resin which is used in crease proofing so that chemically there is no reason why the cross linking should not be as full and as extensive with cyanoethylated cotton as with cotton itself. Infact, as far as the wrinkle and crease resistance is concerned, this appears to be borne out because the two products are substantially the same in this respect. It is; not known why there is such a marked reduction in tensile strength loss and it is not desired to limit the present invention to any theory of action which. would explain the retention of the wrinkle and crease resistance"with'out the" great. loss in tensile" strength.

A further advantage of the present invention lies'in the fact that the resin treated cyanoethylated cottonhas alt of the desirable characteristics of cyanoethylated cotton" such as high degree of resistance to mildew and similar micro-organisms, increased heat resistance" and the like. Another advantage of the present invention is that the resin treatment is not changed and the, same conventional methods may be used with cyanoethylated cotton. No new application technique therefore needs to be learned.

The invention will be described in greater detail in. conjunction with the following examples in which tiie' parts are by weight unless otherwise specified.

EXAMPLE A..piece of 80 x 80 bleached unmercerized cotton. print cloth is treated with acryl onitrile to givea nitrogen cone tent of about 3.4%: The cyanoethylated product is then treated with the followingcomposition: 7.5 parts trimethyl trimethylol melamine.

0.9 part urea:

(This resin 1 0.4 part. mixed isopropanolamine hydrochloride 91.7 parts water The fabric is passed through this compositionandthen through a three bowl mangle with two dips and twdn'ips to. give a pick-up of? about 80% ofthe liquidtcornposition after which it is dried at about 225 F. and then sub jected toa heat treatment'at 350 F. for about one minute. l

A second piece of the x 80 bleached unmercerized cotton print cloth but which has not been cyanoethylated is then treated in the same solution as above by the same procedure. This is used as a control.

The cyanoethylated fabric on soil burial in a standard virulent soil showed no attack after two weeks, whereas untreated cotton cloth is substantially disintegrated.

An examination of the resin treated cotton and cyanoethylated cotton fabrics showed that the cyanoethylated cotton possessed a superior luster.

Pieces of each of the above-treated fabrics are then tested forwrinkle resistance by the method 14-53 de scribed on page 154 of the 1954 edition of the Technical r v 3 Manual and Year Book ofthe American Association of Textile Chemists andColorists and the results follow:

EXAMPLE 2 The procedureof Example 1 is repeated using, however, 10 parts of Resin No. 1 and the treated fabric is 4 EXAMPLE 4 The procedure of Example 1 is followed replacing the methylated trimethylol melamine resin with 3.4% of a 5 reaction product of methylol stearamide and methylated trimethylol melamine plus 13.5% of urea formaldehyde, the catalyst being replaced by ammonium sulfate.

EXAMPLE 5 The procedure of Example 1 is repeated replacing the isopropanol amine hydrochloride with magnesium chloride, the amounts of solids are 5.4% instead of 7%.

EXAMPLE 6 The treated products of Examples 4 and 5 were then 5 tested and the results follow:

Wrinkle recovery 7 After 1 Tensile Elmendorf Initial Sanl. Strength 'lear Total Wash Total Strength Warp Fill Warp Fill Warp Fill Warp Fill Example 4:

80x 80 Cotton 125 130 255 86 87 173 40 26 l. 28 0.75 cyanoethylated Cotton 116 115 231 92 9B 190 52 38 1.60 0.85 Example 5:

80 x 80 Cotton 114 114 228 97 106 203 39 29 1.13 0. 58 Oyanoethylated Cotton 120 126 246 110 110 220 54 29 1.25 0.68 Untreated Cot 53 41 1.62 1; 18 Untreated Cyanoethylated Cotton. 63 43 1. 73 1,35

dried at a low temperature and then subjected to a'heat We claim:

treatment as in the preceding example.

, They are then tested for wrinkle resistance and tensile strength as in the preceding example and the results follow:

EXAMPLE ,3

d The procedure of'Example 1 is repeated using parts of dimethylol ethylene urea resin (Resin No. 2) instead of the methylated trimethylol melamine resin.

They were then tested as in Example 2 and the results follow:

A wrinkle-resistant, crease-resistant, partially-cyano ethylated cotton fabric containing cyanoethyl' groups in an amount not exceeding one such group per' anhydroglucose unit thereof, the cotton fibers containingfrom 3.5 to 5.5% by weight of nitrogen in the form of cyano groups, prepared by applying to said cyanoethylated cotton fabric an aqueous dispersion of about 7.5% by weight of trimethyl trimethylol melamine and a catalyst, drying the so-treated fabric and heating the dried fabric at our- Wrinkle Total Treatment Resistance, Tensile degrees Strength,

r 7 lbs.

Untreated so it so cotton cloth 140 110 Untreated 80 x 80 cotton cloth plus 10% Resin N 0. 2 251 51 Cyanoethylated 80 x 80 cotton cloth 138 116 Cyanoethylated 80 x 80 cotton cloth plus 10% Resin No. 2 251 82 ing temperatures until the trimethyl trimethylol melamine is transformed into a thermoset, insoluble product firmly attached to the surface of said fibers.

References Cited in the file of this patent Compton: Textile Res. Jour., January 1955, pp. 58 and 68-72. a

'Daul: Textile Res. Ioun, March 1955, pp. 246-253.