US2328901A - Nitrogenous condensation product - Google Patents

Description

"Patented se el'z, 1943 UNITED STATES PATENT OFFICE NITROGENOUS CONDENSATION PRODUCT Otto Grimm and Hans Ranch, Darmstadt, Germany, assignors to Riihm & Haas Company,

Philadelphia, Pa.

No Drawing. Application Angust 22, 1939, Serial No. 291,3:29. In Germanydugnst 23, 1938 13 Claims.

polymeric amide such as polymethacrylic amide,

an amine such as dimethylamine, and an aldehyde such as formaldehyde are all high molecular weight substances containing nitrogen. They are soluble in water and form with acid dyes and ing at a temperature of 40 to 50 C.-,.and then applying the dye. In many cases it is' advantageous to dry the impregnated fabric at higher temperatures, for example about 100 C. before dyeing.

When dyeing fabrics, leather or other fibrous material, the dye may be applied first, followed by treatment with the high molecular weight with natural, synthetic and mineral tanning agents, compounds which are insoluble inneutral and acid aqueous olutions. On account of these properties the new products are useful in dyeing fabrics, particularly cellulosic fabrics, and leath-.

er. They are also useful in the process of tanning because the insoluble products which they form with the tanning agents can be easily formed within the leather, thus yielding a good, full leather. a

It is known that cellulosic fabrics cannot be dyed directly with acid dyes. Many methods have been proposed for treating fabrics or fibers of this kind with basic substances so as to introduce basic groups into the cellulose molecule.

This is important becausevery often it is desirable to weave fabrics from two or more fibers, for example cotton and silk. Such fabrics cannot be dyed with a single dye to a uniform color. If basic groups are added to the cellulose molecule, then acid dyes can be used on mixed fabrics and uniform color obtained. Processes for treating cellulose so as to introduce such groups include treatment with ethylene lmine, epichlorhydrine followed by ammonia, impregnation with urea-formaldehyde condensation products, etc. These all have the disadvantage that the fabric must be subjected to a separate treatment to prepare it for dyeing with acid dyes. When using the products of the present invention forthe purpose of fixing acid dyes on cellulosic fabrics, it is only necessary to impregnate the fabric with a solution of the condensation product and then treat the fabric with a solution of an acid dye. By means of this treatment the dye is bound in the fiber. In some cases very uniform dyeings can be achieved by first impregnating the fabric, either hot or cold, with the products of this invention,,wringing out, drynitrogenous products for the purpose of fixing the dye on the fiber. The lightfastness of such dyeings is much better than when the treatment with the new products is omitted.

When used for filling leather, the new condensation products have many advantages over the usual fillers such as kaolin, calcium carbonate, etc. These are usually drummed into the leather along with the fat liquor. The new ,products on the other hand may be added before the fat liquor and, since they form insoluble products with the tanning agent, the actual filling materialis formed directly in the leather. A single treatment of the leather with these materials gives an improved product but still greater improvement is obtained by using relatively large amounts of the new products and then subjecting the leather to a secondtanning treatment. By this means more of the insoluble complex can be incorporated and a fullerleather obtained.

The nitrogenous products of high molecular weight with which the present invention is concerned are prepared by reacting a polymeric amide such as polymethacrylamide, an amine such as dimethylamine, and an aldehyde such as formaldehyde in an acid, neutral or alkaline medium. It is preferable, however, to carry out the reaction in a slightly acid medium in which case the amine is employed in the form of one of its salts.

The amines which can be used in preparing these condensation products are those which ample, amino acids, may also be used in the' reaction.

Formaldehyde is preferred for condensing with the polymeric amide and the aliphatic amines or polymers which yield aqueous solutions of low to intermediate viscosity because, if solutions of high viscosity are employed, difficulties in handling may arise. Joint polymers of the unsaturated acid amides and other polymerizable materials such as acrylic, methacrylic andvinyl esters may be employed, in which case care should be taken that the joint polymer contains a sufilcient proportion of amido groups to render it soluble in water. Water-soluble materials obtained by the partial alkaline hydrolysis of polymeric acid nitriles, such as polyacrylic nitrile may also be used provided they contain a sufiicient proportion of amido groups. Such compounds probably contain unchanged nitrile groups as well as some carboxyl groups. Such compounds may be considered to be joint polymers of acrylic amide and acrylic acid. They are useful in the present invention but are not so efiective as polymers containing a larger proportion of amido roups.

The relative amounts of the reactants can be varied as it is not always necessary to use them in exactly equivalent amounts. However, the amount of aldehyde chosen should be such that there is not much excess, which can be detected by the odor, in the final solution.

Both organic and inorganic acids may be used to establish the desired hydrogen ion concentration in the reaction mass. 0f the inorganic acids those of intermediate strength are preferable, particularly sulfuric, phosphoric, meta-phosphoric, pyrophosphoric, and other polyphosphoric acids. When such acids are employed, the pH of the aqueous solution in which the reaction takes place should be adjusted to about 4. The organic acids are preferably the aliphatic carboxylic acids and may be monobasic or polybasic. They may also contain hydroxyl groups. Examples of such acids are formic, acetic, propionic, butyric, oxalic, lactic and tartaric acids. When organic acids are used, the .solution in which the reaction takes place should be less strongly acid then when the inorganic acids are employed. A pH of 6 to 6.5 is desirable for the organic acids.

When an acidic medium is employed in the initial stages of the reaction, it is preferable to employ a weak acid, such as acetic acid, because the precipitate, which forms momentarily when, for example, the third ingredient is added to the reaction mixture of the other two, dissolves more readily in the presence of a weak acid. The process may also .be carried out in the presence of strong acids and the products so obtained are particularly suitable for fixing tanning mate- The order in which the reactants are mixed maybe varied. For example, the amine may first be neutralized and the solution made slightly acid, after which the aldehyde is added and then the polymeric amide. If desired, the polymeric amide may be added to the amine solution followed by the aldehyde. The amine and the aldehyde may be reacted in the absence of acid and the polymeric amide added to the product In this case the reaction product of amine and aldehyde may be acidified before the addition of the amide. The polymeric amide may be reacted with the aldehyde and the amine reacted with this product with or without the addition of acid.

The nitrogenous condensation products made according to the invention may be used, as pointed out above, for filling leather because they react not only with vegetable tans but also with those prepared from sulfite cellulose extracts, synthetic and mineral tans. Because of the fact that the new products are universal precipitants for all of these tanning agents they have many advantages over precipitants previously-used,

such as glue. Glue has the disadvantage when used for this purpose that, whereas it precipitates the vegetable tans, it does not precipitate all synthetic tans, unless these have been treated in some way to yield insoluble products with the glue. The precipitation of some synthetic tans by glue can be prevented by the presence of sulfite cellulose tans. This is understandable because the sulfite cellulose extracts are never precipitated by glue.

For precipitating tanning agents with the products made according to the invention, the pH of the solution may vary from 4.0 to 7.3 but is preferably adjusted to about 5.5. This range is practically the same as is used in preparing the products so that in many cases the solution in which the reactions are carried out may be employed without further treatment. When products which have been made in the absence of acid are to be used as precipitants, sufiicient acid should be added before or during precipitation so as to adjust the solution to the proper pH.

The precipitates formed from the new products and tanning agents are soluble in alkaline solutions, for example in ammonia, but are reprecipitated when these solutions are acidified. When using the products to precipitate sulfite cellulose tans about equal parts by weight of the two reagents are used calculated on the dry material.

Generally speaking, the precipitants should be used at concentrations of less than 10%I P eferably about 4%, for the fixation of tanning agents in leather because, it higher concentrations are used, there is danger of the leather becoming tacky.

When usedas a mordant for dyeing leather, textiles, etc., the new products result in a. fuller coloring and a fixation of the dye on the surface.

The new products thus have a wide field of application. They may, as has been indicated above, be used to precipitate certain materials on animal fibers. They may also be used for the same purpose on other fibrous materials, such as paper and textiles. The presence of fiber is not essential. Soluble dyes may, for example, be precipitated from their solutions thus yielding colored pigments and tanning agents or polymethacrylic amide may be precipitated in the form of an adherent mass, the adhesive properties ofwhich may be varied or eliminated by suitable changes in its composition.

The following examples will illustratethe invention which, however, is not limited to the exact reagents and conditions of reaction given as it may be otherwise practiced within the scope of the appended claims.

may be used.

Example 1 135 parts by weight of a aqueous solution of polymethacrylic amide is added in portions. In place of the polymethacrylic amide, a mixed polymer made from methacrylic amide and a small amount of methacrylic acid or acrylic acid The resulting solution may be used to precipitate the lignin-sulfonic acid from crude sulfite liquors, for example 1000 g. of the crude liquor are treated with 94 ccm. of the above solution and 400 com. of water. The resulting precipitate is filtered and dissolved in 40 com. of 2.5% ammonia. Any undissolved material is filtered. The clear solution may be used for filling leather. By making slightly acid the material is reprecipitated and is fixed in the leather in an insoluble condition. p I

The ammoniacalsolution may also be used for impregnating textiles, paper, artificial leather,

etc.

In place of ammonia, other alkaline compounds may be used, for -example','sodium hydroxide or dimethylamine.

Example-2 '50 g. of as dimethylamine solution is mixed with 80' g. of 96% acetic acid giving a solution having a pH of about 6. To this solution 3..

. of formaldehyde is added and the solution heated. To this there is added, in portions,. 100

g. of a 10% aqueous solution of polymethacrylic amide. Before the addition of a further portion the precipitate which forms must be redissolved valueof about 5.2.

The solution may be used as an assistant in dyeing; for example, chrome-tanned leather is by'boiling. .The product thus obtained has a pH neutralized as usual and .mordanted with one 125g. of ortho-phosphoric acid (tech. cone.)

is added slowly to 300 g. of dimethylamine. The solution is heated and 300 com. of 30% form--' aldehyde added. 1000 g. of 10% aqueous solu- 30% dimethylamine. The resulting solution has a pH of about 4. This solution is boiled and 110 parts of a 10% aqueous solution of polymethacrylic amide added in portions. The resultin solution may be used forfilling of chrome leather. This can be carried out as follows:

The skins after the usual pickling are pretanned with 80% of water, 2% of salt, and 3% of chrome alum calculated on the weight of the skins. The skins are then drummed in a fresh bath consisting of 10% of the above solution and 20% of water. After an hour the skins are tanned in the usual way with a basic chromium tanning material. This process yields a chromeleather with a full feel and a firm grained flank.

.Erample 5 g. of 30% formaldehyde is added to 90 g. of 35% aqueous dimethylamine solution. To this solution there is added while heating 180 g. of a 10% aqueous solution of polymethacrylic amide in portions. Before each addition the precipitate resulting from the previous addition must be dissolved by boiling. This solution is.acidified by the addition of 144 ccm. of 96% acetic acid and may then be used for fixing tanning materials or asan assistant in dyeing.

' Example 6 0.21 parts by weight of a'2.5% aqueous soluamide. After heating for some time agood precipitating agent for tanning material is obtained.

The furfurol may be replaced by crotonaldehyde, acetaldehydeor allylaldehyde.

. Example 7 0.5 parts byweight of 85% of ortho-phosphoric acid are stirred with 5.3 parts by weight of a 3.3% aqueous solution of fl-naphthylaminehydrochloride and'the resulting mash of crystals tion of polymethacrylicamide is added, in portions, to the hot solution. Before the addition of any portion the precipitate'formed from' the previous one must be re'-dissolved by boiling.

The resulting solution may beused for filling leather tanned with synthetic tans, e. g., condensation productsofphenolor cresolsulfonic acid with formaldehyde, condensation products of the sulfonic acids of naphthalene and its homologues with formaldehyde, phenol-aldehyde conden sation products, condensation products of Example4 1 22 parts by weight of 30% aqueous formaldehyde solution is added to 45 parts by weight of v dimethylamine sulfate solution containing about is dissolved by heating 0.5 part of a 2.5% aqueous solution of furfurol are added to the clear solution whilst stirring, followed by one part of a 10% solution of polymethacrylic amide. After heating for some time a product is obtained which can be used for fixing acid dyes and tanning materials containing acid groups.

- Ewample 8 .0.05 .part by weight of acrolein are first stirred with 5.3 parts by weight of 3.3% aqueous solution; of p-naphthylaminehydrochloride. 0.5 part by weight of 85% ortho-phosphorie acid and then 1 part by weight of a 10% solution poly methacrylic amide are added. After heating for some time a product is obtained which is a good precipitant for acid dyes and tanning materi- "als containing acid groups.

This'solution may beused to fix dyes on cotton, artificial silk or linen fabrics. The fabric is first treated with the solution and. the dye is then applied at about C. The linen may be dyed with a 0.2% solution of Diamine pure blue FF (Schulz Farbstofftabellen, vol, 1, No. 510). The artificial silk. may be dyed with a 0.05% solution of Chrome Leather black RW extra (Schulz Suppl. vol. 1, page '71). The'cotton may be dyed with a 0.2% solution of the diamine pure blue or with a 0.1% solution of Benzo dark green B (Schulz, vol. II, page 32, and Suppl..vol. II, page 1.24). The colors thus obtained are much faster than those obtained with the same dyes on untreated fabrics.

Example 9 2.5 parts by weight of propylamine are mixed with 1.1 parts by weight of 85% formic acid and 2.5 parts by weight of 30% formaldehyde are added. After heating, parts of a 10% aqueous solution of an interpolymerization product consisting of 80 parts by weight of polymethacrylic amide and 20 parts by weight of methylacrylate are added in portions. The insoluble residue is filtered oflL The solution may be used for prev cipltating tanning materials from sulfite pulp.

Example 11 5 parts by weight of 33% ethylamine are mixed with'2 parts by weight of concentrated sulphuric acid and 3.2 parts by weight of 30% formaldehyde are added to this solution while stirring. After heating, 10 parts by weight of a 10% aqueous solution of an interpolymerization product consisting of '75 parts by weight of polymethacrylic amide and 25 parts by weight ethylmethacrylate are added in portions and the heating is continued. The product may be used for the precipitation of tanning material.

Example 12 138-parts by weight of 42% dimethylamine are heated with parts by weight of 30% formaldehyde for 2 to 3 hours under a reflux condenser until the liquid which is first cloudy has become absolutely clear, To'this alkaline solution are added while stirring 2130 parts by weight-of a 3.3% aqueous solution of polyacrylic nitrile which has been saponified with 65% of the amount of soda lye necessary for complete saponification, and 50 parts by weight of 30% formaldehyde.

After heating. for 30 minutes the solution is rendered acid with 11 parts by weight of 96% acetic acid to pH 5.

The product may be used for fixing tanning material.

Instead of the 3.3% aqueous solution of polyacrylic nitrile there may be used a 3.3% aqueous solution of an interpolymerization product of 10 parts by weight of methylmethacrylate and 90 parts by weight of acrylic nitrile which has been saponified with of the amount of alkali necessary for complete saponification,

Example 13 .21 parts by weight of 50% dibutylamine are mixed with 14' parts by weight of orthophosphoric acid. To the solution are added 7.5 parts by weight of 30% formaldehyde. After heating, 42.5 parts by weight of a 10% aqueous solution of polymethacrylic amide is added in Example 14 30 parts by weight of 50% cyclohexylamine are mixed with 21 parts by weight of 96% acetic acid,

To this solution are added 7.5 parts by weight of 30% formaldehyde. After heating, 42.5 parts by weight of a 10% aqueous solution of polymethacrylic amide is added infportions while stirring and the heating is continued until the solution becomes absolutely clear.

Example 15 25.5 parts by weight of 50% piperidine are mixed with 12.5 parts by weight of 85% formic acid, To this solution 4.2 parts by weight of allylaldehyde is added. While heating and stir:- ring, 42.5 parts of a 10% aqueous solution of polymethacrylic amide is added in portions and the heating is continued until the solution becomes absolutely clear.

Example 16 32 parts by weight of 50% benzylamine andand washed out as usual and then drummed for one hour with 100% of water (calculated on the shaved weight) and one per cent of th solution prepared according to Example 2.

After this time the leather is dyed in a fresh bath with 1% Acid leather brown EG (Schultz FarbstofiZ-Tabellen, vol. II, P ge, 189) and 100% of water at 65 C. After the complete absorption of the dyestufi the leather is fatliquored, usually in a. fresh bath. A particularly full and even dyeing is obtained.

Example 18 Chrome tanned glove leather is neutralized, washed out and fatliquored as usual and then drummed for one hour in a fresh bath with 100% of water and 2% of the solution prepared according to Example 2.

Then the leather is dried and wet back. It is then drummed with 100% water of 65 C. (calculated on the weight of the wet leather), 0.8%

lution has become absolutely clear.

Cotton brown RVN; 0.8% Cotton brown GNJ (Schultz Farbstoff-Tabellen, vol. II, page 30 and Suppl. vol. II, Pa e 123) and 0.5% Acid leather brown EGR (Schultz Farbstoff-Tabellen, Suppl. vol. II, page 240). until the dye solution is completely exhausted. The leather is then fatliquored, set out and dried as usual.

This treatment of the leather causes a complete absorption of the dye.

Example 19 g. of desized rayon staple fiber are drummed with 250 g. of the impregnation product prepared according to Example 2 and 250 com. waterfor v5 minutes and then pressed. It is dried at 3040 C. and dyed with a solution containins 1 g. Acid anthracene brown RH extra (Schultz Farbstoff-Tabellen, vol. I, Nr. 134) to 1 liter water at 90 C., then washed and dried.

The resulting color is much fuller than when the impregnation product is omitted.

Example 20 500 g. of desized rayon staple fiber are drummed -with 800 g. of the impregnation product prepared according to Example 2 and 800 com. water for 5 minutes and then pressed. It is dried at 45-50 C. and dyed with a solution containing 2 g. Nigrosin WLA (Schultz Farbstoff-Tabellen, vol. I, Nr. 986 and Suppl. vol. II, page 56) to 1 liter water at 90 C., then washed and dried.

This acid dye cannot be fixed directly on the desized rayon staple fiber but after impregnation of the fiber with the product described in Example 2, the dye can be permanently fixed.

Subject matter pertaining to the use of the condensation products of a polymeric amide, an amine and an aldehyde in the treatment of leather is claimed in application Serial No. 291,- 328, filed August 22, 1939, now Patent 2,205,355. Subject matter relating to the use of these condensation products in the dyeing of fabrics and leather is claimed in copending application Serial No. 291,327, filed August 22, 1939.

We claim:

1. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together a non-aromatic amine having at least one hydrogen atom attached to the nitrogen atom thereof, an aldehyde, and a water-soluble polymeric amide.

2. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together an aliphatic amine having at least one hydrogen atom attached to the nitrogen atom thereof, an aldehyde, and a water-soluble polymeric amide.

3. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together in an aqueous solution at a pH of about 4 to about, 7.3 an aliphatic amine having at least one hydrogen atom attached to the nitrogen atom thereof, formaldehyde, and a water-soluble polymeric amide.

4. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together in aqueous solution a secondary aliphatic amine, formaldehyde,and a water-soluble polymeric amide.

5. The process of preparing nitrogenou materials of high molecular weight which comprises reacting by condensing together in an acidic aqueous solution dimethylamine, formaldehyde, and polymeric acrylamide.

6. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together in an acidic aqueous solution dimethylamine, formaldehyde, and polymeric methacrylamide.

7. The process of preparing nitrogenous materials of high molecular weight which comprises reacting by condensing together in an aqueous solution at a pH of about 4 to about 10 a watersoluble polymeric amide resulting from the partial hydrolysis of polyacrylonitrile, formaldehyde, and dimethylamine.

8. The product obtained by condensing together a non-aromatic amine having at least one hydrogen atom attached to the nitrogen atom thereof, an aldehyde, and a water-soluble polymeric amide.

9. The product obtained by condensing together in an aqueous medium an aliphatic amine having at least one. hydrogen atom attached to the nitrogen atom thereof, an aldehyde, and a water-soluble polymeric amide.

10. The product obtained by condensing together in an aqueous medium a secondary aliphatic amine, formaldehyde, and a water-soluble polymeric acrylamide.

11. The product obtained by condensing toether in an aqueous medium a secondary aliphatic amine, formaldehyde, and a water-soluble polymeric methacrylamide.

12. The product obtained by condensing together dimethylamine, formaldehyde, and a water-soluble polymeric methacrylamide.

13. The product obtained by condensing together dimethylamine, formaldehyde, and a water-soluble polymeric amide resulting from partial hydrolysis of polyacrylonitrile.

I OTTO GRIMM. HANS RAUCH.