US2602017A - Monomethylol dimethyl hydantoin to shrinkproof cellulose fabrics - Google Patents

Description

Patented July 1, 1952 MONOMETHYLUL DIMETHYL HYDANTOIN TO SHRINKPROOF CELLULOSE FABRICS Leo Beer, Montreal, Quebec, Canada No Drawing. Application December 1, .1949, Se-

rial No. 130,609. 1949 INTRQDUCTION This invention relates to the chemical shrinkage control of textile fabrics.

The process is applicable to' cellulosic textiles. They may be made from natural cellulose or regenerated cellulose or mixtures of one or both of the said types with up to about 50% of a cellulose ester of an organic acid, for example, cellulose acetate.

PRIOR ART Many attempts have been made to develop and perfect processes which control the shrinkage of such fabrics. For this purpose, fabrics have been treated with monoor dialdehydes such as formaldehyde or glyoxal in the presence of acids or in the presence of a salt which is acid reacting per se or becomes acid during processing, for example, during baking at elevated temperature. This results in deterioration in tensile strengths and abrasion resistance which is especially serious in the case of cotton and is often accompanied by discoloration.

The aldehyde is applied either as a watery solution or as a compound which only splits off the bound aldehyde by treating with acid or in the presence of a salt which is acid or becomes acid at elevated temperature. Compounds like hexamethylentetramine, for instance, require the stoechiometric quantity of acid for their complete decomposition. If the quantity of acid for this purpose is not sufficient, the excess of hexamethylentetramine acts as a buffer and counteracts the reaction between the aldehyde and the cellulosic material, and as a result, the intended effect is unsatisfactory.

Despite this, hexamethylentetramine has been recommended as a protective agent. In British Patent 460,201 (1936) the inventors recommend adding a certain quantity of hexamethylentetra-mine to the impregnating baths to protect the cellulosic material against the destructive action of the free acids. The reaction takes place as follows:

Other acids can be used. V

The applicant in U. S. Patent 2,441,859 recommends the decomposition of the hexamethylentetramine with volatile organic acids by steaming the fabrics, previously impregnated with a watery solution of hexamethylentetramine and dried, in a steam chamber, in the presence of an excess of acetic or formic acid. Y

2 Claims. (Cl. 8----116.3)

In Canada November 22,

If watery solutions of aldehydes in the presence of an acid, for catalizing the reaction are applied, certain disagreeable disadvantages are well-known. Working with formaldehyde solu- I tions, is, beside other unfavourable consequences, a very unpleasant operation at all times. Therefore; more recently, 5 the application of glyoxal has been recommended. According to U. S. Patent 2,436,076, 'glyoxal is used, preferably in the presence of oxalic acid with subsequent drying and-baking the goods at elevated temperature. But, whereas rayon fabrics are made shrink-proof to 'a satisfactory degree and the shrinkage tendency significantly curbed in the case of cotton fabrics, the former display a loss in the range of 20% in tensile strength and the latter in the range of 50%.

In following the procedure of the applicants co-pending U. S. patent applications 722,955, filed January 18, 1947, now U. S. Patent No. 2,484,545,

mally prior to the anti-shrink procedure, only certain types of dye-stuffs can be used. In the present process, the treated fabric need only be neutralized and washed for a short time, for example, from about 5 to about 10 minutes at about 35 C. to 45 C.

' OBJECTS It is the object of the present invention to eliminate the mentioned disadvantages and inconveniences by treating textile fabrics which are formed predominantly of natural cellulosic materials or regenerated cellulose, including mixtures containing up to about 50% of cellulose acetate fibres with dilute aqueous solutions of a specific type of aldehyde compound which gives off the bound aldehyde by treating either with acid solutions or in an alkaline medium, for stabilizing them against shrinkage but with no appreciable loss, in tensile strength and having an increased resistance to abrasion without any tendency to diSCOlOIiIlg by baking-curing.

APPLICANTS DEVELOPMENT The applicant has now found that this object dition to release much of the formaldehyde. n

the other hand, the monomethylol dimethyl hydantoin gives off all the bound formaldehyde under milder conditions. v Therefore, itisthe preferred formaldehyde donor. It contains 18.98% combme f rmaldehyde which is vai able chemic l u e. tis ver solub e .i w ter, and s lits of the form ldehyde as wel u de alkaline conditions as ac drnedia- .llb i erated forma deh e in st tu nasccnd issreact s w th he cellu ose at e eva ed temperatu e- Usin the e-mentioned sub t nces, unde a aline con t n the r action pro u form b t-ween th fo ma dehyde a d the ce lu ose-i not v r stab e, wher asqu ra co ditio s probabl po voxymethv enebt er l kages are term d h cha e t bl to y rol sisand a ch ract iz d by a r duc d, we ng cap c y wh n oak d n aterland t r e reduce the sh in a e d n y o th re ed eellulosic material. If the treatment is carried out under controlled conditionstheifabr-ics;show no appreciable loss in tensilestreng-th. An improved reslstance to abrasi n willi esult and thereis not even the slightest tendency-for discoloring. ,Dim th l hydantoin robably remainsas a y- -;I utt imp-the t at fa ric a ter ba ing w ich be easily removedby a short-washing opera tion. The f e. a ic t eat d by this ew method show no tendency.toward-.chlonne retention.

.Ithau ers-spec fic obi e o thcpresen nven i n o s ure I tabilization of a the aforesaid types o t tile fa rics against shr nkage but without significantly impairing their tensile stren th and mprov ng their a a on resistance wher in the fibers are wetteu with dilute watery solution of monomethylol dimethyl 'hydantoin. dr e andsub eque tly baked at 1 0C.- or hi h until the desired shrinkage control has beenisecured, i. e. a substantial reaction between the cellulose and the liberated formaldehyde has taken place.

Other objects and features of the invention will be apparent from the following description. Broadly speaking, the invention includes cmploying nearly neutralaqueous solutions of monomethylol dimethyl hydantoin in the presence of a non-volatile organic acid catalyst capable of giving these solutions a -pI-I from about 2 to'about 2. 5. Suitable acids are for example, oxa c acid, lactic acid, citric acid, tartaric acid and other non-volatile organic acids or mixtures thereof strong enough to catalyze the reaction'between the aldehyde and the textile material. The acid must be such as to give a pH within the range from about 2 to about 2.5 which is a preferred range of the invention. The formaldehyde cellulose reaction must take place within the fibres of the natural or regenerated cellulose.

other means allowing a pick-up of a predeter- .mmedperoentage such as 100% liquid retention According to the invention, any form of the 15 on the basis of the dry weight of the goods. They are then tensionless dried and finally cured or balzedfor about 2 to 5 minutes.

A drying rangeof to C. and a baking temperature within C. to C. is usually preferred. However, the exact formulation of the solution as to components and strength as well as the conditions of drying and, baking may vary depending pon the construction, composition and form of 'the'textile material. After curing, the fabrics are neutralized with an alkali, for example, soda ash, eventually soaped, rinsed, hydro-extracted and dried without tension be- ;fore putting into industrial channels of trade. or

before making the physical measurementsreif erred to in the comparative tests below.

Before treatment of the fabric all traces .of starch, gums, glue or natural resins and other sizing agents should be removed in order to permit the aqueous treating solution to penetrate the fabrics and enter the heart of the fibres.

Whereshrinkage control of fabrics is desired. the dimensions at which the. fabrics are finally dried must be predetermined by a preliminary wash test. 'If desired, t e hand or body of the goods treated can be modified in the direction of either softness or .a stiffer finish at will by the introduction to the impregnatin baths of suitableagents such as cation softeners for the formereffect or such vegetable or animal colloids as starches, ums, glues, gelatines, modified starches, or solutions or dispersions .of polyvinyl alcohol, etc. forthc latter effect. The procass is usually carried out inthe absence .ofiany Phenolic, or -amidic compounds capable of formingresinous bodies with aldehyde under the conditions.

When fabrics are treated by this new method in theabsence of phenolic or amidiccompounds, theydo not show any tendency toward chlorine retention. Fabrics treated by the present invention are characterized by permanent stability against shrinkage and even successive washings at the boil .do not affect the results.

In the aqueous wettingasolution the suggested range of concentration of the monomethylol dimethyl hydantoin is 1%. to 7.5% inclusive (preferably; to 5% inclusive) basedupon the weight of the treating solution. The amount of the stabilizing compound or compounds employed is such as to furnish from about 2% to about 1.5% (preferably about 2% to about 1.0%) of active available formaldehyde based on the weight .of the aqueous solution.

Fabrics of viscose or .cuprammonium yarns so processed are further improved as borne out by the fact that they show less tendency to fuzz during washing as compared to an untreated material similarly washed.

This invention will be more clearly understood by reference to the following examples. It is to be understood, however, that these examples are merely illustrative of the process and that the invention is not limited thereto, but rather is defined in'the appended claims. In the examples, the term check has the meaning of untreated or original material.

EXAMPLE 1 C. Cotton R. Spun Rayon Monomethylol Dimethyl, g Hydantoin, g Oxalic Acid Anhydrous Sodium, g Sulphate Igepal CTA Extra Water to make.

The fabric was subjected to treatment to remove any traces of starch, gums, glue, natural resins or other sizing agents present and dried. It was then passed through an aqueous impregnating solution of the above composition. The solution had a pH of about 2.2. After the fabric was passed through the solution and was well wetted out (this required about 5 seconds immersion) it was squeezed to remove solution inexcess of 100% pick-up based on the dry weight of the fabric. It was then dried without tension on a pin-tenter frame in air at about 83 C. to the dimensions that the fabric possessed before impregnating. The dried, tentered fabric was then cured in circulating air at about 135 C. for about 5 minutes in the case of the cotton and at about 149 C. for about 3 minutes in the case of rayon. 5

' The fabric after curing was removed from the tenter frame and soaped, rinsed, hydroextracted, and dried without tension. To me'asure their shrinkage in washing, samples were amen Warp Tensile Strength Abrasion (Taber Cycles) (inlb a) 0 Cotton R Rayon .0 Cotton QR Rayon As it can be seen'by the results obtained. the

' amount of NaSOa addedto 'thebath'has not to be exaggerated, especially in manage-er [stabilizing rayon fabrics but good results in every respect are achieved if carnea-durnndr the right conditions.

fabric were treated respectively for the purpose of obtaining shrink-proof efiects with aqueous solutions of the following compositions.- The check was not treated. I Monomethylol dimethyl' hydantoin 1 'grams25 The samples were immersed with the above solutions as described in Example #1 and after drying cured.

Cotton .4 minutes at j i Spun rayon 3 minutes at V 149 and washed and dried as previously described.

laundered together with the check sample by 45 C Cotton the accelerated 1 hour wash test described in U. S. A. Federal specification CCC-T-lQlA Cotp Shrinkage (i per sesdl ton Wash Test. f

Other samples were subjected to tensile sample Identm. Treatedd. IHour ss from Gain over 5 :Wash on a1 Corn esi strengths and abrasion resistance measurements. 0 Scmmd Test r6551. shr i im The following shrinkages were observed based upon the measurements. Check 8.5 -5.5 -5.5 #1 a. 1 0. a s. 9 1.6

-3.1 0.9 4 1 (2'. Cotton [Warp Shrinkage in percentages] R- RAYON (EPUN) Treated lHour Loss from Gain over 8- 25 12.5 g gi and Wash Original compressive 0 Secured Test Length shrinkage 5 0. 2 5. 2 7. 3

5. 5. 8'26 W T n 11 St gth arp e S 6, Ten 45 78 L 22 (mlbs) Abrasion (Taber Cycles) -0.5 as 1.1 -;o.1 -4.o4 0.91 65 0 g3 4 13 0,37 CCotton RRayon OCOtton RRayon Check 54 65 soc-e 200-250 R. SPUN RAYON #1 4s 61 825-850 600 -9.17 12.7 3.3 8 In all cases, a very good stablization efiect is -4.11 -0.56 obtained. Moderate loss in tensile strength on :22 in? cotton material. No loss in tensile strength in -4.5 -4.17 rayon material. In both cases considerable'improved abrasion resistance.

V as 3 'ojusgs mnq spr the following composition. The

check wa not treated.

described in Exam le 1 and mine-d vat-tel, d ying for i, rmlnut eai l if'qe. Wa h d and dried s-n v u iy-d scr bed-in Ex mple I [Warp Shrinkage (in percentagesJ] The achieved stabilization eiiect is very satisfactory, practically without any change in tensile strength-and without any discoloring effect.

I 1a m;. ,t

.1- ma Process of sh nka e cont l a t xtil fabric selected from the group consisting of natural cellulose, regenerated cellulose and their mixtures with up to about 50% of cel1ulose aceitate, the steps of impregnating said fabric vwith an aqueous solution of monomethyiol dimethyl substantially retained nydannmisam aq o tio q a ina mm 11. to 7 by weight -of monomethylol dim-ethyl hydantoin which, upon bakin decomposes to form from 0.2 to 1.5% of available active formaldehyde and containing a non-volatile organic acid in an amount such as to give to the solution a pH of from about 2 to about 2.5, squeezing the surplus liquid from the fabric, drying said fabric, baking the dried fabric at a temperature of from to C. =for a time sufficient to effect reactio'n' between liberated formaldehyde and the textile fabric; and neutralizing and Washing said i'abrict'o remove acid and reaction Joy-products thereby to provide a fabric which has substantially permanent stability against shrinkage in successive washings at the boil and which has its color and tensile strength.

2. The process of claim l, wherein the nonvolatile organic acid is selected from the group consisting of oxalic acid, lactic acid, citric acid,

and tartaric acid.

LEO BEEB.

R F RENCES CITED The following references are of record in the file of hthis patent: v r A .7

UNITED STATES PATENTS OTHER REFERENCES Chemical and Engineering News, November 3, 1947, page 3243, and February 9, 1948,11, 4'15.

Claims (1)

1. IN A PROCESS OF SHRINKAGE CONTROL OF A TEXTILE FABRIC SELECTED FROM THE GROUP CONSISTING OF NATURAL CELLULOSE, REGENERATED CELLULOSE AND THEIR MIXTURES WITH UP TO ABOUT 50% OF CELLULOSE ACETATE, THE STEPS OF IMPREGNATING SAID FABRIC WITH AN AQUEOUS SOLUTION OF MONOMETHYLOL DIMETHYL HYDANTOIN, SAID AQUEOUS SOLUTION CONTAINING FROM 1 TO 7% BY WEIGHT OF MONOMETHYLOL DIMETHYL HYDANTOIN WHICH, UPON BAKING, DECOMPOSES TO FORM FROM 0.2 TO 1.5% OF AVAILABLE ACTIVE FORMALDEHYDE AND CONTAINING A NON-VOLATILE ORGANIC ACID IN AN AMOUNT SUCH AS TO GIVE THE SOLUTION A PH OF FROM ABOUT 2 TO ABOUT 2.5, SQUEEZING THE SURPLUS LIQUID FROM THE FABRIC, DRYING SAID FABRIC BAKING THE DRIED FABRIC AT A TEMPERATURE OF FROM 120 TO 150* C. FOR A TIME SUFFICIENT TO EFFECT REACTION BETWEEN LIBERATED FORMALDEHYDE AND THE TEXTILE FABRIC, AND NEUTRALIZING AND WASHING SAID FABRIC TO REMOVE ACID AND REACTION BY-PRODUCTS THEREBY TO PROVIDE A FABRIC WHICH HAS SUBSTANTIALLY PERMANENT STABILITY AGAINST SHRINKAGE IN SUCCESSIVE WASHINGS AT THE BOIL AND WHICH HAS SUBSTANTIALLY RETAINED ITS COLOR AND TENSILE STRENGTH.