US2297731A - Processes for rendering textiles water repellent - Google Patents

Description

Patented Oct. 6, 1942 PROCESSES FOR RENDERING TEXTILES WATER REPELLENT Ernst Waltmann andEdgar Wolf, Krefeld, Germany, assignors to Heberlein Patent Corporation, New York, N. Y., a corporation of New York No Drawing. Application August 10, 1939, Serial No. 289,395. In Germany February 19, 1936 4 Claims.

This invention relates to processes for producing water repellent fibrous materials and products therefrom.

This application is a continuation-in-partof our copending application Serial No. 126,521 filed February 18, 1937, now Patent No. 2,173,029.

.We have found that acyl carbamic acid chlorides may be employed for the production of water repellent fibrous materials.

The principal object of the present invention is to provide a simple process to increase waterrepellence in materials such as cotton, jute, linen, hemp and various artificial silks and wool, presenting advantages ove the known fatty acid chloride and fatty acid anhydride processes.

We have found in accordance" with ourinvention that acyl carbamic acid chloride deriva tives having the general formula R.CONH.COCl

can be employed with great success for rendering textiles water-repellent. In the formula just mentioned and in the appended claims in which said formula is employed, R is intended to designate an alkyl, cycloalkyl or aralkyl radical conit is believed. However, we do not Wish to state w unequivocally that a chemical reaction with the textile material occurs, as we are not sure that such is the case. The result of this action is to produce a surface structure which is water-repellent.

Materials falling under the formula mentioned above are distinguished by extremely high rapidity of action towards textile materials, particularly towards cellulose and cellulose derivatives. It

is necessary only to bring the textile material incontact with the acyl carbamic acid chloride as by passing the textile material briefly through a solution of the substance in benzine or a suitable solvent and immediately thereafter subjecting it for several minutes to an elevated temperature, usually 60 C. or above.

Impregnation of the textile materials with the halides herein mentioned may be carried out in any desired manner with or without the use of organic solvents by means of emulsiflcation in an embodiments of the invention for producing waclaims.

aqueous solution by soaking, spraying orthe like.

To avoid any weakening of the fibres by the hydrogen halide split off from the carbamic acid chloride during the drying process the textile materials are advantageously treated before im pregnation takes place with slight aqueous solutions of sodium hydroxide, sodium carbonate or sodium acetate.

Also organic bases such as pyridine may be added to the solutions of acyl carbamic acid chlorides in organic solvents.

It is also possible to add the acyl carbamic acid chlorides mentioned herein to the spinning solution of viscose or to the spinning solution of cellulose esters or ethers in order thus to combine the process of producing water-repellence with the spinning process.

Also one may treat the fibers of cellulose or cellulose derivatives immediately after the spinning process with the chlorides herein mentioned to obtain water-repellence. The addition of catalytic agents, such as for the purpose of securing the desired effect, may be made but such addition is not necessary. The water-repellent effect secured by these treatments'resists domestic washing. After thorough rinsing out with soap employed in such washing and'drying the textile material again manifests water-repellent properties. It is also resistant to dry cleaning.

The following examples represent preferred ter-repellence in accordance with the manner in which I now prefer to practice it. It is to be understood that these examples are illustrative and the invention is not to be considered as limited thereto except as indicated in the appended Examples 1. A poplin from mercerized cotton is passed through a 1% solution of stearic acid-butyl-carbamic acid chloride in benzol for 4 seconds at a temperature of 25 C. The solution also contains 10 grams of pyridine per liter. After evaporating of the benzol the material is heated for minutes to 60 C. F.). The effect is proof to washing with soap, as Well as to the solvents customary in dry cleaning.

2. A cotton tent? cloth is passed through an aqueous solution of IO-grams per liter of sodium acetate, dried, and then passed through a 1% in carbon tetrachloride for 4 seconds at a temperature'of 25 C. After evaporating of the solvent the material is heated 60 minutes to 70 C. (158 F.). The resulting effect is similar to that of Example 1.

3. A clothing material of cuprammonium silk is passed through an aqueous solution of 5 grams per liter of sodium carbonate, dried and then passed through a 15% solution of montanic acid carbamic acid chloride in carbon tetrachloride for 3 seconds at a temperature of 25 C., and after evaporation of the solvent is heated for 30 minutes to 70 C. The material then becomes water-repellent. The effect is proof to washing with soap, as well as to the solvents customary in dry cleaning.

7 4. A wool muslin is passed through a 1% so lution of behenic acid ethyl carbamic acid chloride in carbon tetrachloride for 3 seconds at a temperature of 25 C. After evaporation of the solvent the materialis heated for 30 minutes to 75 C.

5. To 1000 parts of a viscose solution containing 7.7% cellulose there are added 20 parts of stearic acid carbamic acid chloride dissolved in 60 parts of carbon tetrachloride. The whole is homogeneously mixed and is spun in well known fashion. The precipitating bath which we prefer to employ contains ammonium sulfate.

6. To 100 parts of a 25% solution of cellulose acetate in a mixture of 950 parts of acetone and 50 parts of water, there is added 1000 parts of acetone containing 20 parts of stearic acid carbamic acid chloride. The resulting spinning solution is forced through a spinning nozzle into a current of warm air in the known manner.

The filaments so formed are, when dry, subject-.

ed to a dry heat for 10 minutes at 120 C. The resultant filaments have water-repellent properties which are resistant to washing and dry cleaning treatments.

The amount of the compound deposited in all of the above examples on the textile materials will naturally vary with the weight of the material and its receptivity. We have found that ordinarily an amount of the ester equal to about 0.5%-2% of the material is sufficient to give the effect.

The materials produced in accordance with the above examples show a high degree of waterrepellence. They show a lesser absorption of moisture as compared with the known processes for treatment with fatty acid chlorides and fatty acid anhydrides; They show also greatly improved durability toward dry-cleaning, soap washing, etc. as compared with these previous materials. The .feel and hang of the materials having water-repellence as produced above, has not been substantially altered.

The process of the invention, particularly as set forth in the specific embodiments above, may be carried out with simple apparatus at relatively small expense and in a relatively short time.

In the claims where the expression. textile material" is employed, it is intended to cover materials containing fibers, yarns, fabrics, or other forms of cotton, jute, linen, hemp or rayon including viscose, cuprammonium, or other precipitated cellulose or derivatives of cellulose such as acetyl cellulose, as well as wool in such various forms.

Whie the invention has been described in detail according to the preferred manner of carrying out the process, it will be obvious to those skilled in the art after understanding the invention, that changes and modifications may be made therein without departing from the spirit or scope of the invention, and it is intended in the appended claims to cover all such changes and modifications.

What is claimed as new and desired to be secured by Letters Patent, is:

1. A process for ennobling textile material which comprises impregnating the material with a carbamic acid chloride having the formula R.CONH.COC1, in which formula R is a higher molecular radical containing an alkyl radical of at least 10 carbon atoms and with the impregnated material substantially dry, heating it at an elevated temperature to increase the waterrepellency thereof.

2-. A process for ennobling textile material which comprises impregnating the material with an aliphatic acyl carbamic acid chloride which contains an alkyl radical of at least 10 carbon atoms in the presence of an alkaline substance to produce an'alterationof the surface and with the impregnated material substantially dry, heating it at an elevated temperature to increase the water-repellence of said material.

3. The process for ennobling artificial silk which comprises impregnating the artificial silk with montanic acid carbamic acid chloride and with the impregnated material substantially dry, heating it at an elevated temperature to increase the water-repellence thereof.

4. A process for ennobling textile material which comprises impregnating the material with an aliphatic acyl carbamic acid chloride which contains an alkyl radical of at least 10 carbon atoms and with the impregnated material substantially dry, heating it at a temperature of at least C. to increase the water-repellence of said material.

ERNST WALTMANN. EDGAR WOLF.