US2923644A - Blends of urea-formaldehyde resins and sulfonated thiourea-formaldehyde resins, and method of making and using same - Google Patents

Description

BLENDS OF UREA-FORMALDEHYDE RESINS AND SULFONATED THIOUREA FORMALDEHYDE RESINS, AND METHOD OF MAKING AND US- ING SAME William F. Herbes, Bridgewater Township, Somerset County, N.J., assignor to American Cyanamid Company, New York, N.Y., a corporation of Maine No Drawing. Application December 2, 1957 Serial No. 699,900

9 Claims. (Cl. 260-103) The present invention relates to stable, water-soluble, hydrophilic, potentially thermosetting resinouscompositions containing a urea-formaldehyde condensate and a thiourea-formaldehyde condensate, and more particularly to physical blends possessed of superior properties composed of partially polymerized, partially alkylated, watersoluble urea-aldehyde condensates, and bisulfite-modified, partially polymerized, water-soluble thiourea-formaldehyde condensates, in which these components are present in certain critical ratios. Further, this invention relates to the process for preparing such resins and to their use for imparting flame-resistant durable finishes, which are substantially free from dusting or flaking, when properly applied and cured to textile materials, and in particular nylon textile materials.

Heretofore, urea-formaldehyde and thiourea-formaldehyde condensates have been proposed as textile treating agents, as have mixtures of these materials, either employed alone or in conjunction with other components, such as, for example, melamine-formaldehyde condensates and/ or certain cyclic ureas, as for example, ethylene urea, 1,2-propylene urea and their formaldehyde condensates and alkylated derivatives. Still further, it has been disclosed that certain of these resinous components, either alone or in combination with others of the class mentioned hereinabove, may be modified, as for example, with rather large amounts of metalbisulfite to produce resinous compositions possessed of utility in textile finishing.

Many of these compositions, while possessing certain desirable advantages, suifer rather significant or important deficiencies, which in one manner or another limits their utility. Thus, for example, textile finishing compositions of the prior art have, in many instances, been possessed of extremely limited stability, i.e. they hydrophobed or separated out crystalline material at standard stability test-temperatures very shortly after preparation. Such a characteristic limits the utility of the resinous material in that in many cases it could not be shipped to the finisher, because of the limited time of stability, and many finishing mills are not equipped to prepare such resinous mixtures.

In the case of bisulfite-modified resinous finishes, the degree of polymerization present in such a mixture prepared by a one-pot process and the presence of rather large amounts of combined bisulfite therein, while resulting in acceptable stiifening, when cured properly,

notable discoloration of white goods has been en' countered, thus greatly limiting the utility of such resin.

Still further, such bisulfite-modified resinous materials have been produced which possess satisfactory stability, will impart desirable stiifness and flame resistance to the treated fabric, and in particular to nylon, but suffer from the deficiency that when applied to the nylon in amounts sufiicient to impart the properties of stiflness and flame retardance, do, when cured, result in dusting or flaking when the treated fabric is subsequently subjected to mechanical action such as the type encountered in the han- United States Patent prepared separately.

2 dling of goods after cure, including necessary operations by converters.

Accordingly, ,it is an object of the present invention to prepare a stable, water-soluble, hydrophilic, potentially thermosetting resinous composition suitable for use as a textile finishing agent, possessed of 'good stability, and which, when properly cured on textile fabrics, and in particular nylon textile material, imparts a durable, stiff hand thereto, as well as flame resistance.

It is a further object of the present invention to provide such a resinous composition which, when applied and properly cured, does not produce significant undesirable discoloration of the finished textile material.

It is a further object of the present invention to provide such a resinous composition which, when properly applied and cured as on nylon textile material, in addition to having the other desirable attributes set forth hereinabove, is substantially free from dusting or flaking when the fabric so treated is subjected to subsequent mechanical action.

These and other objects and advantages of this invention will become apparent from the detailed description set forth hereinbelow.

According to the present invention, a stable hydrophilic, potentially thermosetting resinous product is provided, which comprises a physical blend' of a partially polymerized, partially alkylated, water-soluble urea-aldehyde condensate and a partially polymerized, water-soluble, bisulfite-modified thiourea-formaldehyde condensate containing in parts by weight'of the blend 55 to 88 parts of the alkylated urea-aldehyde condensate and from between 45 and 12 parts of the bisulfite-modified thioureaformaldehyde condensate.

The partially polymerized, partially alkylated, watersoluble urea-aldehyde component of the blend is prepared by reacting in aqueous medium relative proportions of from between 1.50 and 2.25 moles of a watersoluble aliphatic aldehyde with l moleof urea at a pH of from between 7 and 10, at a temperature of from between 70 and 100 C. for a period of time from between .25 and 2.0 hours.

Preferably, the aldehyde-urea condensation is carried out in the presence of between 0.3 and 2.0 moles of an aliphatic alcohol containing from 1 to 3 carbon atoms. While it has been determined that this is not an essential condition, during this stage of preparation of the urea component, the presence of the alcohol in the reaction medium functions to eliminate the presence of excess water in the reaction medium, which inhibits condensation.

After condensation with the aldehyde, the pH of the reaction mixture is adjusted to from between 4 and 6 with a suitable acid, as for example, oxalic acid, formic acid or other suitable acids well known to those skilled in the art, and if alcohol is not already present it is added in an amount equal to from between 0.3 and 2.0 moles per mole of urea. Thereafter, the urea-aldehyde condensate is alkylated at a temperature of from between 70 and 100. C. for from .25 to 2.0 hours, after which the resulting syrup is neutralized by the addition of caustic or other suitable neutralizing agent.

The partially polymerized, bisulfite-modified thioureaformaldehyde component of the present invention is It is. one ofthe important features of .the present process that the constituents be in the final composition'in a purely physical association, and that the components of the product be prepared separately. Subsequently, it has been found that when the final composition is a physical blend, as opposed to a onepot process product, certain apparently inherent characteristics which render the one-pot" process final product more diificult to cure and thus adversely affect coloration on a finished nylon material, as well as dusting or flaking of the resin finish from the treated textile material, are avoided.

By the use of the term one-pot process, as employed herein, it is meant a process in which all of the components of the final composition are added to a given reaction kettle, either simultaneously or in stages, without withdrawals or separation from said vessels, prior to the formation of the final product. By way of example, if in the process of this invention, after the alkylation of the urea-aldehyde component the thiourea component was added and then reacted in the presence of the urea component, such would be termed a onepot process.

In the preparation of the alkylated urea-aldehyde component, it is preferred to employ relative proportions of from 1.9 to 2.1 moles of formaldehyde with 1 mole of urea at a temperature of from between 90 and 100 C. at a pH of from between 7.5apd 9 for from .25 to .75 hour. During alkylation, it is preferred to alkylate and also partially polymerize at a pH of from between 4.8 and 5.2 and at a temperature of from 90 to 100 C. for from 0.5 to 1.0 hour reaction time. Thereafter, the reaction mixture is neutralized, as by the addition of sodium 11ydroxide or other suitable alkaline material, to a pH of between 7 and 8, and is cooled to less than about 40 C. and preferably to room temperature.

The alkylation of the urea-aldehyde condensate is normally carried out until the reaction product has a viscosity of between 3000 and 6000 and preferably from about 4500-5500 centipoises at 25 C. It has been deterimned that in carrying out the reaction employing the conditions and times set forth hereinabove, a reaction product being possessed of such viscosity characteristics is produced.

In the preparation of the bisulfite-modified thioureaformaldehyde component, preferably relative proportions of between 0.75 and 1.0 mole of formaldehyde, .02 and .04 mole of a suitable, water-soluble bisulfite or sulfite capable of rendering bisulfite under the resin-forming conditions of this invention, and 1 mole of thiourea are reacted at a pH of between 7.5 and 9 and at a temperature of from between 80 and 100 C. for from 1 to minutes. Thereafter, the partially polymerized reaction mixture, which is a clear syrup, is cooled to less than about 40 C. and preferably to room temperature.

As noted hereinabove, these two essential components of the present invention are then blended to provide a composition containing in 100 parts of blend from between 55 and 88 parts by weight, based on resin solids, of the partially polymerized, partially alkylated, watersoluble urea-aldehyde reaction product and from between 45 and 12 of the bisulfite-modified, partially polymerized, water-soluble thiourea-formaldehyde condensate. Preferably, these components are blended in relative amounts of from between 65 and about 80% of the urea-aldehyde component and from between about 35 and 20% of the sulfite-modified thiourea-formaldehyde component.

The final composition has a visosity from between about 500 and 850 centipoises at 25 C., containing in 100 parts of blend from between 20 and 35% of the thiourea condensate and optimumly from between 24 and 30% thereof, and from between 65 and 80% of the urea condensate and optimumly from between 70 and 76%.

The final blend may then be clarified, as through a pressure filter, and is a clear, stable solution, which remains clear and free from hydrophobing at 12 C. for a time period greater than two months, will remain free from crystallization at 25 C. for at least three months, andwill remain free from crystallization at 37 C. for at least one month. Further, the resinous blend prepared in accordance with the present invention will not hydrophobe when diluted with 3 parts of water at 20 '4 C. after three months of storage at temperatures of 25 C. and below.

The aldehyde employed in preparing the urea and thiourea condensates in accordance with the present invention may be selected from a wide variety of watersoluble aliphatic aldehydes capable of producing watersoluble components when employed under the reaction conditions of the present invention. These include formaldehyde, acetaldehyde, propionaldehyde, glyoxal and the like. For purposes of the present process, formaldehyde, either as formalin solution or in its more concentrated form, such as paraformaldehyde, is preferred. Paraformaldehyde, as a concentrated form of formaldehyde, is greatly preferred in the present process in that it eliminates the requirement for the removal of substantiabamounts of excess Water from the final product, and it is specifically desirable in the preparation of the alkylated urea-formaldehyde component in that the presence of large amounts of water appears to impede the alkylation of this component.

The alcohol employed in alkylating the urea-formaldehyde component is an aliphatic alcohol containing from 1 to 3 carbon atoms. Thus, for example, methyl, ethyl, propyl and isopropyl alcohol or mixtures thereof are the alcohols contemplated by the present invention. Of these, methyl alcohol is greatly preferred in that the solubility and stability characteristics of the final resinous component are more easily regulated and enhanced.

The bisulfite modification of the thiourea-formaldehyde component is preferably achieved by the employment of water-soluble alkali metal bisulfites, as for example, sodium, potassium, lithium, and the like, bisulfite, although sulfite which yield bisulfites under the resin-forming contions of the present invention or mixtres of these two materials may obviously be employed. Preferably, the bisulfite is added as sodium bisulfite or sodium metabisulfite, which readily hydrolyzes under the conditions of the present process to yield 2 moles of sodium bisulfite.

The partially alkylated and preferably partially methylated, partially polymerized urea-formaldehyde component employed in the blend of the present invention is water soluble and is composed of monomeric material and low order polymeric material, as for example, dimers, trimers, tetrimers, pentamers, and the like. The degree of polymerization imparted by the processing in accordance with the present invention of this component, while producing these low order polymers, results in a product which is a soluble, stable, clear solution, and one which will not hydrophobe when diluted with 3 parts of water at 20 C. after 3 months of storage at temperatures of 25 C. and below. On a monomeric basis, this material contains from between about 1.5 to 2 moles of combined formaldehyde and from between about 0.1 and about .8 mole of combined alcohol, preferably methanol.

The partially polymerized, bisulfite-modified thioureaformaldehyde component is water soluble and stable, and is composed of monomer and a low order of polymers of slightly lower order of magnitude than that of the alkylated urea-formaldehyde component. This component, on a monomeric basis, contains to between about .7 and about 1.0 mole of formaldehyde per mole of thiourea and between about .01 and about .035 mole of bisulfite per mole of thiourea.

it is a principal feature of the present invention that the blend prepared in the above-described manner and of the above-described composition, when properly applied and cured to texile material, and in particular to nylon material, and preferably nylon net fabrics, im parts a durable, stiff finish thereto, which is flame resistant or which does not increase the combustibility of the nylon netting and is free from dusting or flaking when the finished fabric is subjected to mechanical action.

Nylon nettings, such as nylon Rachelle net, may be treated with the resin blend of the present invention by applying it thereto, as by pad-bath, spraying, immersion or other suitable application techniques, in amounts of from between about 1 and.70% solids, based on-the weight of the fabric, and preferably from between about 30 and 65% solids, based on the weight of the cloth. Thereafter, the treated. fabric is cured, as for example, from 5 minutes .at 250 F. to five seconds at 450 F. and preferably from 90'sec'onds at 290 to 60 seconds at350 F. to a Water-insoluble state in the presence of acid-curing catalysts 'such as ammonium bromide, ammonium chloride, certain mixed isopropanolamine hydrochlorides and the like, to impart a finish having the qualities described above. Suitable catalysts of the type referred to above and others well known to those skilled in the art may be employed in amounts of between .50 and 1 /2 to based on the weight of the resin solids, and preferably in amounts from between 0.50 and 1%.

In orderto illustrate the present invention, the following examples are given byway of illustration, in order that said invention may be more fully understood. No details therein should be construed as limitations on the present invention, except as they appear in the appended claims. All parts and percentagesare by weight unless otherwise designated.

EXAMPLE 1 crystals dissolved in 30 parts of water. Refluxing of this mixture was continued until the viscosity of the syrup was between 5000 and 5500 centipoises at 25 C. This required about 45 rninutes-afterthe acid addition.- Thereafter, the pH was adjusted to above 7 with sodium hydroxide and the batch cooled to 40 C.

Into a three-necked flask equipped as in' jExample 1(A), there are charged 636parts.,(7.85.moles) of 37% formaldehyde containing approximately 7% methanol. The pH of this'mixture was adjusted to 9.0 with sodium hydroxide and 54 parts (1.64 moles) of 9l%' parafor'maL.

dehyde, 30 parts (0.28 mole) of sodium 'bi'su'lfite and 728 parts (9.48 moles) of thiourea wereadded. The mixture was heated to the reflux (96 C.:) and cooled immediately to 40 C. or below. The preparation of this component after all of the reactants were included in the reaction vessel required 90 minutes.

A IOO-part blend in accordance with the present invention was then prepared by blending 70 parts -by-weight of Example 1(A) which contained 80% of active ingredients, with 30 parts by weight of Example 1(B) containing 70% active ingredients. The blended product was a clear, water-white stable syrup containingabout 76% of active ingredients.

EXAMPLE 2.

Nylon marquisette was immersed in a bath containing 80 parts by Weight of the blend. prepared in Example 1(C), 0.48 part by weight of ammonium chloride as catalyst and 19.52 parts by weight of water.. After immersion for a time sutficient to permit complete penetration of the marquisette fabric, the treated netting was passed'through a' squeeze roll to impart a wet pick-up of about 80%, after which the fabric was-dried and cured for l'minute at 310 This treated fabric, containing.

48% of the resin solids, based on the dry weight ofthe fabric, had a desirably smooth, stiff finish, substantially freeof discoloration and tendency to dust off "under mechanical action. The treated, fabric was found to safely meet the standards described in the Flammable Fabrics Act .(P.A.'88-83rd Congress) even after being laundered, whereas a similar piece of nylon netting, treated with a conventional thermosetting textile resin (a methylated methylol melamine or commercial methylated urea-formaldehyde condensate) was classified as a fabric subject to rapid and intense burning.

EXAMPLE 3 Into a suitable reaction vessel equipped as in Example 1(A) there are charged 160 parts (5.0 moles) of methanol, 30 parts of 5-N sodium hydroxide and 396 parts (12.0 moles) of 91% para-formaldehyde. After heating to 70 to 80 C. to depolymerize and dissolve the paraformaldehyde, the pH was adjusted to 8.9. 360 parts (6.0 moles) of urea were then added and the charge heated to the reflux (96? C.) where it was held for 30 minutes. After the addition of 3.0 parts of oxalic acid crystals to bring the pH of the reaction mixture down to 4.9, the reflux was continued for an additional 30 minutes. The pH was then brought to above 7.0 with sodium hydroxide and the charge cooled to about 40 C. a

To a reaction vessel equipped as in Example 3(A), there were charged 256 parts (3.16 moles) of 37% formaldehyde (7%. methanol) at a pH of 9, 14 parts (0.13 mole) of sodium bisulfite and 240, parts (3.16 moles) of thiourea.

A blend in accordance'with the present invention was then made by physically mixing 2 parts of the product prepared in Example 3(A) above and 1 part of the product prepared in Example 3(B). .This blend contained 69.5% of the partially polymerized, partially methylated urea-formaldehyde condensate on an active ingredients or solids basis and 31.5% of the bisulfitemodified thiourea-formaldehyde component on a solids or active ingredient basis. The resulting syrup, which was stable and water soluble, was then applied to nylon marquisette netting, as in Example Z'hereinabove and the resulting fabric was fire resistant and the finish was durable and substantially free from dustingor flaking off when subjected to mechanical action. The treated nylon fabric was somewhat less stifl or gave a less stiff hand than that fabric treated with the blend prepared in accordance withExample 1(C) hereinabove, but was that the 'acid reflux (methylation) period was extended from 30 minutes to 45 minutes.

The partially polymerized, bisulfite-modified thioureaformaldehyde component was prepared by substantially the same procedure employed in Example 3(B) above.

The components prepared in Examples 4(A) and 4(B) hereinabove were blended in a manner and in a propor- The charge was then heated to the reflux, held at reflux for 10 minutes, and cooled to about tion similar to that of Example 3(C) hereinabove. Upon application of the product to nylon marquisette netting in a manner. similar to that described in Example 2, the treated or finished fabric was possessed of properties of substantially the same character, with the exception that the finish imparted was not quite as stiff as that produced in Example 2, but was noticeably stiffer than that provided by the blend prepared in Example 3(C).

EXAMPLE 5 The procedures of Examples v4(A) and (B) were followed with the exception that no sodium bisulfite was employed to modify the thiourea component prepared in Example 4(B). Hydrophobing of this component took place at about 80 C. while heating it to the reflux.

EXAMPLE 6 The procedure of Example 5 was followed, except that the thiourea-formaldehyde component was heated to only 60 C. Employing this technique, this component did not hydrophobe, but the final blend became turbid after one month at 12 C. It is believed that the formation of this turbidity under these conditions is predicated on the lack of polymerization in this componet of the reaction mixture. Thus, it appears necessary that some polymerization is essential to prevent turbidity of the blend during storage. Thus, in contrast, the resinous blends prepared in accordance with Example 4 remained completely clear after more than 2 months storage at 12 C.

EXAMPLE 7 The partially methylated, partially polymerized, watersoluble urea-formaldehyde component and the partially polymerized, water-soluble bisulfite-modified thiourea formaldehyde component were prepared in a manner similar to that employed in Examples 1(A) and 1(3)- hereinabove.

25 parts by weight of the preparation of .1(B) containing 70% solids were blended with 75 parts by weight of the component prepared in Example 1(A) containing 80% solids. Application of this blend in accordance with the procedure described in Example 2 resulted in the impartation of a durable, stiff finish to the fabric and one which was free from undesirable flaking or dusting as the result of mechanical action, but the flame retardancy was reduced, rendering the blend less desirable for commercial usage.

EXAMPLE 8 A blend was prepared in accordance with Example 7 (that is, employing the partially polymerized, partially methylated urea-formaldehyde component of Example 1(A) and the partially, polymerized, bisulfite-modified thiourea-formaldehyde component of Example 1(8)) except that 40 parts by weight of the product of Example 1(B) containing 70% active ingredients or solids and 60 parts by weight of the product of Example 1(A) containing 80% active ingredients or solids was prepared. This blend was applied to nylon marquisette netting in accordance with the procedure outlined in Example 2. The treated fabric possessed the necessary degree of flame retardancy, was substantially free fromdusting or flaking as a result of mechanical action, but thehand of the treated fabric was noticeably softer than that achieved in Example 7. Since it is a necessary attribute of the present resin blend to impart a durable, desirable stitf hand, this resinous blend was considered unacceptable for commercial usage.

The urea condensates prepared in accordance with the above-described procedures and employable in the present invention and the thiourea condensate employable therein typically analyze as. follows:

Urea condensate Percent Moles Ure 38.2 1. 00 Total HOHO 37.7 1.97 Free HGHO.. 3.7 0.19 Combined HCHO 34.0 1. 78 Methylol HCHO 11.2 0. 59 Total methanol 17. 4 0. 86 5. 9 0. 29 11. 5 0. 57

T hiourea condensate Percent Moles Thiourea 49. 9 1. 00 Total HCHO 17. 6 0. 89 Free HCHO 1. 0 0.05 00 "nbined ECHO" 16. 6 0.84 Methylol HOHO 18. 2 0.92 NaHSO; 2. 6 0.036

while the analysis fora typical blend containing 70% of the urea condensate and 30% of the thiourea condensate is as follows:

Blend Percent Moles Methylol HO HO 13. 3 0.99 Total methanol 12. 2 0. Free me 4. 1 0.30 Combined methanol 8. 1 0.55 NaHsO 0.8 0.017

As has been pointed out, the products of the present invention are particularly useful and applicable in the field of textile treating, and more specifically in the field of nylon finishing, wherein frequently in the case of white goods, as for example the type employed in evening dress nettings, petticoats and the like, it is desirable that the fabric has a stiff, flame-resistant, nondusting finish. However, the resinous blend of the present invention may be employed for other purposes, as for example, in the paper industry, as a chemical intermediate, and the like.

While the use of the resinous blend of this invention has been described primarily in conjunction with the finishing of formed nylon fabrics, it should be understood that fibers, yarns' or fabrics of nylon alone or in blends with synthetic or natural fibers are contemplated. Such blends should contain at least 50% nylon in combination with such materials as cotton, linen, wool, regenerated cellulose, such as viscose rayon and cuprammonium rayon, cellulose acetate, acrylic fibers, polyester fibers, and the like.

I claim:

1. A process for preparing a stable, hydrophilic, potentially thermosetting resinous product comprising a physical blend of a partially polymerized, partially alkylated, water-soluble urea-aldehyde condensate and a bisulfite-modified, partially polymerized, water-soluble thiourea-formaldehyde condensate containing in parts by weight of the blend 55 to 88 parts of the former and 45 to 12 parts of the latter, which comprises reacting in aqueous medium relative proportions of 1.50 to 2.25 moles of a water-soluble aliphatic aldehyde with 1 mole of urea at a pH of from 7 to 10 and at a temperature of from 70 to 100 C. for from'.25 to 2 hours, adjusting the pH of the reaction mixture to a value between 4.0 and 6.0, and reacting said urea-aldehyde condensate to a temperature of between 70 and 100 C. for from .25 to 2.0 hours with from 0.3 to 2.0 moles of an aliphatic alcoholcontaining from 1 to 3 carbon atoms, and there- -9 after neutralizing the reaction mixture, and reacting in aqueous medium relative proportions of .4 to 1.4 moles of formaldehyde, 0.1 to 0.6 mole of a material selected from the group consisting of a water-soluble bisulfite and sulfites capable of yielding bisulfites under the conditions to be described, and 1 mole of thiourea at a pH value between 7.0 and 10.0 and at a temperature of from between 50 and 100 C. for from 1 to 30 minutes, and thereafter blending these respective components in the weight ratios set forth above.

2. A process according to claim 1 wherein the formaldehyde, the bisulfite and the thiourea are reacted at a temperature of from between 80 and 100 C. for from 1 to minutes, and wherein the amount of water-soluble bisulfite is from between .02 and .04 mole per mole of thiourea.

3. A process according to claim 1 wherein the physical blend contains in 100 parts by weight thereof 65 to 80 parts of the partially alkylated urea-formaldehyde condensate and 35 to 20 parts of the bisulfite-modified thiourea-formaldehyde condensate. v

4. A process according to claim 1 in which the alkylated urea-aldehyde condensate is a methylated ureaformaldehyde condensate.

5. A process according to claim 1 in which the urea and aldehyde are condensed in the presence of an aliphatic alcohol containing from 1 to 3 carbon atoms.

6. A process for preparing a stable, hydrophilic, potentially thermosetting resinous product comprising a physical blend of a partially polymerized, partially methylated, water-soluble urea-formaldehyde condensate and a bisulfite-modified, partially polymerized, water-soluble thiourea-formaldehyde condensate containing in 100 parts by weight of the blend 55 to 88 parts of the former and 45 to 12 parts of the latter, which comprises reacting in aqueous medium relative proportions of between 1.9 and 2.1 moles of formaldehyde with 1 mole of urea at a pH of from 7.5 to 9.0 and at a temperature of from between 90 and 100 C. for from between .25 and .75 hour, adjusting the pH of the reaction mixture to between 4.8 and 5.2, and reacting said urea-formaldehyde condensate at a temperature of from between 90 and 100 C. for from .5 to 1 hour, with between 0.7 and 1.0 mole of methyl alcohol, and thereafter neutralizing the reaction mixture and reacting in aqueous medium relative proportions of between 0.75 and 1.0 mole of formaldehyde and from between .02 and .04 mole of sodium bisulfite and 1 mole of thiourea at a pH between 7.5 and 9, and at a temperature of between 80 and 100 C. for from 1 to 5 minutes, and blending these respective components in the weight ratio set forth above.

7. A stable, hydrophilic, potentially thermosettmg resinous product comprising a physical blend of a partially polymerized, partially alkylated, water-soluble urea-aldehyde condensate and a partially polymerized, water-soluble bisulfite-modified thiourea-formaldehyde condensate containing in 100 parts by weight of the blend 55 to 8 8 parts of the former and 45 to 20 parts of the latter, said alkylated urea-aldehyde component being prepared by reacting in aqueous medium relative proportions of 1.50

to 2.25 moles of a water-soluble aliphatic aldehyde with 1 mole of urea at a pH of from 7.0 to 10.0 and at a temperature of from 70 to 100 C. for from .25 to 2.0 hours, adjusting the pH of the reaction mixture to a pH of between 4.0 and 6.0, and reacting said urea-aldehyde condensate at a temperature of 70 to 100 C. for from .25 to 2.0 hours, with 0.3 to 2.0 moles of an aliphatic alcohol containing from 1 to 3 carbon atoms, and thereafter neutralizing the reaction mixture, said bisulfite-modified thiourea component being prepared by reacting in aqueous medium relative proportions of 0.4 to 1.4 molesof formaldehyde, .01 to .06 mole of a material selected from the group consisting of water-soluble bisulfite and sulfites capable of yielding such bisulfite under the conditions to be described and 1 mole of thiourea, at a pH range of from 7.0 to 10.0 and a temperature of from between and 100 C. for from 1 to 30 minutes, and thereafter blending these respective components in the weight ratio set forth above.

8. A stable, hydrophilic, potentially thermosetting resinous product comprising a physical blend of a partially polymerized, partially methylated, water-soluble ureaformaldehyde condensate and a partially polymerized, water-soluble, bisulfite-modified thiourea-formaldehyde condensate containing in 100 parts by weight of the blend to parts of the former and 35 to 20 parts of the latter, which comprises reacting relative proportions of between 1.9 to 2.1 moles of formaldehyde with 1 mole of urea at a pH of from 7.5 to 9.0 and at a temperature of from between to C. for from between .25 and .75 hour, adjusting the pH of the reaction mixture to between 4.8 and 5.2, and reacting said urea-formaldehyde condensate at a temperature of from between 90 and 100 C. for from .5 to 1 hour, with between 0.7 and 1.0 mole of methyl alcohol, and thereafter neutralizing the reaction mixture and reacting in aqueous medium relative proportions of between 0.75 and 1.0 mole of formaldehyde and from between .02 and .04 mole of sodium bisulfite and 1 mole of thiourea at a pH between 7.5 and 9, and at a temperature of between 80 and 100 C. for from 1 to 5 minutes, and blending these respective components in the weight ratio set forth above.

9. A process for treating nylon to impart a durable, stifi hand and flame-resistant finish thereto, which finish is substantially free from dusting when the fabric is subjected to mechanical action, comprising treating said nylon with from between 30 and 65% resin solids of the product defined in claim 7 and thereafter curing said resin for from 90 seconds at 290 F. to 60 seconds at 310 F. to a waterinsoluble state in the presence of from between 0.50 and 1% catalyst, based on the weight of the resin solids.

References Cited in the file of this patent UNITED STATES PATENTS 2,062,171 Fuchs Nov. 24, 1936 2,582,840 Maxwell Jan. 15, 1952 FOREIGN PATENTS 836,798 France Ian. 25,- 1939

Claims (1)

1. 7. A STABLE, HYDROPHILIC, POTENTIALLY THERMOSETTING RESINOUS PRODUCT COMPRISING A PHYSICAL BLEND OF A PARTIALLY POLYMERIZED, PARTIALLY ALKYLATED, WATER-SOLUBLE UREA-ALDEHYDE CONDENSATE AND A PARTIALLY POLYMERIZED, WATER-SOLUBLE BISULFITE-MODIFIED THIOUREA-FORMALDEHYDE CONDENSATE CONTAINING IN 100 PARTS BY WEIGHT OF THE BLEND 55 TO 88 PARTS OF THE FORMER AND 45 TO 20 PARTS OF THE LATTER, SAID ALKYLATED UREA-ALDEHYDE COMPONENT BEING PREPARED BY REACTING IN AQUEOUS MEDIUM RELATIVE PROPORTIONS OF 1.50 TO 2.25 MOLES OF A WATER-SOLUBLE ALIPHATIC ALDEHYDE WITH 1 MOLE OF UREA AT A PH OF FROM 7.0 TO 10.0 AND AT A TEMPERATURE OF FROM 70 TO 100*C. FOR FROM .25 TO 2.0 HOURS, ADJUSTING THE PH OF THE REACTION MIXTURE TO A PH OF BETWEEN 4.0 AND 6.0, AND REACTING SAID UREA-ALDEHYDE CONDENSATE AT A TEMPERATURE OF 70 TO 100*C. FOR FROM .25 TO 2.0 HOURS, WITH 0.3 TO 2.0 MOLES OF AN ALIPHATIC ALCOHOL CONTAINING FROM 1 TO 3 CARBON ATOMS, AND THEREAFTER NEUTRALIZING THE REACTION MIXTURE, SAID BISULFITE-MODIFIED THIOUREA COMPONENT BEING PREPARED BY REACTING IN AQUEOUS MEDIUM RELATIVE PROPORTIONS OF 0.4 TO 1.4 MOLES OF FORMALDEHYDE, .01 TO .06 MOLE OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF WATER-SOLUBLE BISULFITE AND SULFITES CAPABLE OF YIELDING SUCH BISULFITE UNDER THE CONDITIONS TO BE DESCRIBED AND 1 MOLE OF THIOUREA, AT A PH RANGE OF FROM 7.0 TO 10.0 AND A TEMPERATURE OF FROM BETWEEN 50 AND 100*C. FOR FROM 1 TO 30 MINUTES, AND THEREAFTER BLENDING THESE RESPECTIVE COMPONENTS IN THE WEIGHT RATIO SET FORTH ABOVE.