US2582870A - Water-repellent textile fabrics resistant to fungi and bacteria - Google Patents

Description

Patented Jan. 15, 1952 WATER-REPELLENT TEXTILE FABRICS SISTANT T FUNGI AND BACTERIA Paul V. Keyser, Jr., Moorestown, John W. Schick, Camden, and Howard D. Hartough, Pitman,

J., assignors to Socony-Vacuum Oil Com-' pany, Incorporated, a corporation of New York No Drawing. Application July 25, 1947, Serial No. 763,743

'1 Claims. I

The present invention relates to the treatment of textiles and, more particularly, to the treatment of textiles to protect them against mildew and to impart water-repellent properties or characteristics.

The textile fabricating art has always been confronted with the problem of protection of its products against mildew. With the development of means to impart water-repellency to textiles, the need to make textiles resistant to the growth of mildew has increased. However, a serious obstacle to the entirely satisfactory treatment of textiles to impart water-repellency thereto has been the difllculty encountered in waterproofing textiles which have been associated with substantially water-insoluble inorganic material.

For example, some of the most widely used agents for water-proofing textiles are members of the group of quaternary ammonium salts represented by the general formula where R is a long chain alkoxy group or an amide of a long chain carboxylic acid and CsHsN is a pyridine radical.

It has been recognized for some time that copper salts retarded or eliminated the growth of mildew on textiles. However, it is known that advantage cannot be taken of the excellent waterrepellency imparted by the quaternary ammonium salts of the general formula and the effect of copper salts on the spreading of mildew on textiles to combine the two and provide a mildew-proofed, water-repellent textile fabric. In fact, most agents commercially employed to impart water-repellency to textile fabrics do not impart the property of waterre'- pellency to textiles which have previously been impregnated with copper salts or other foreign 2 to provide textile fabrics impregnated with a water-insoluble or only slightly water-soluble salt of a metal known to inhibit or retard the spread! ing of mildew on textile fabrics or to eliminate the growth of mildew on textile fabrics to a substantial extent.

The present invention likewise has as an object imparting water-repellency to fibrous material associated with substantially water-insoluble inorganic material.

Other objects and advantages will become apparent from the following description.

In the copending application Serial No. 763,744 filed July 25, 1947, in the names of John W. Schick, Howard D. Hartough and Darwin E. Badertscher,

now Patent No. 2,559,260, a method of treating fibrous textile material to impart the property of water-repellency is disclosed. Briefly, the aforesaid method comprises impregnating the aforesaid fibrous material with an aqueous solution of a water-soluble derivative of nitrogenous resinous material containing at least one 5-membered heterocyclic radical per polymer unit and preferably at least one thiophene radical per polymer unit. After the fibrous material is impregnated with the water-soluble derivative, the impregnated fibrous material is treated to convert the water-soluble derivative to the insoluble mother material, the fibrous material washed substantially free from foreign contaminating non-nitrogenous material, the so-treated fibrous material subjected to contact with formaldehyde, washed and heat-treated at low temperatures.

It now has been discovered that contrary to prior experience with other agents capable of imparting water-repellency to fibrous textile material that such fibrous material can be mildewproofed and then made water-repellent by impregnation with the aforesaid nitrogenous resinous material.

In general, the novel process comprises impregnating the fibrous organic material with a water-soluble salt of a metal such as copper, zinc, mercury, etc., converting the aforesaid watersoluble salt in situ to a water-insoluble salt and then impregnating the salt impregnated fibrous organic material with the aforesaid nitrogenous resinous material in the manner set forth in the aforesaid copending application.

The following examples are illustrative but not limiting of the novel process.

EXAMPLE I A sample of cotton poplin 7' inches square was contacted with an aqueous solution of copper acetate. (Other water-soluble salts of copper, meraaazlavo cury, zinc and the like with acids of about the same or lower dissociation constant may be used.) The concentration of water-soluble copper salt may be varied within wide limits but a practical concentration is about 5 to about weight per cent. The textile impregnated with the watersoluble metal salt is then treated in any suitable manner with a compound which through metathesis produces a water-insoluble metal salt in situ and a water-soluble derivativeof the anion of the water-soluble metal salt. For practical purposes a textile impregnated with a copper salt is treated preferably with an aqueous solution of trisodium phosphate. The concentration of trisodium phosphate may vary within wide limits but a concentration of 5 to weight per cent is preferred for practical operation. The reaction may be represented by the following equation:

where Act=CHsCOO.

The textile impregnated with the substantially water-insoluble metal salt is then dried and contacted, for example, by immersion in an aqueous bath, with the nitrogenous, resinous material containing at least one 5-membered heterocyclic radical per polymer unit. For industrial purposes at this time it is preferred to use a water-soluble derivative of nitrogenous resinous material containing at least one thiophene nucleus per polymer unit in the form of an aqueous bath containing about 6 weight per cent of the nitrogenous thiophene resin. The textile now impregnated with a substantially water-insoluble metal salt and a water-soluble derivative of the nitrogenous resinous material is treated to convert the water-soluble resinous material to a Water-insoluble form. A satisfactory method for achieving this end comprises immersing the impregnated cloth in an aqueous solution of sodium acetate. A concentration of 10 weight per cent sodium acetate has given satisfactory results. Thereafter, the textile impregnated with substantially waterinsoluble metal salt and substantially waterinsoluble nitrogenous resinous material is washed in cold water to remove loosely attached surface precipitate. The washed or rinsed textile is then contacted with formaldehyde. At the present time for practical reasons it is preferred to use an aqueous alkaline bath containing formaldehyde and an alkali. Suitable concentrations are about12 weight per cent formaldehyde and about 1 weight per cent sodium hydroxide. Of course,

lesser and greater concentrations may be used and'other alkalies such as potassium hydroxide, alkali metal carbonates and, briefly, aqueous alkaline formaldehyde solutions of about the same pH as an aqueous 1 weight per cent NaOH- 12..

A sample of cotton poplin 7 inches square was subjected to a cycle comprising immersion in aqueous copper acetate and then immersion in aqueous trisodium phosphate three times. Thereafter, the so-treated poplin was impregnated with a nitrogenousthiophene P lymer in the manner described hereinbefore. After two hand-washings the treated textile gave a spray-rating of 70.

Both of the samples produced as described hereinbefore were subjected to severe laundering in a washing machine to determine the effect upon the spra rating. The results are tabulated in the following table:

. Table [launder-ability vs. spray rating of cotton impregnated with CuAPOd, and thiophene water-repellent.

Spray Rating I Time (min.) in W ashing Machine 140 One treat of Three treats 5% Cu++ 0:59;, Cu++ After the final washing, a sample of the cloth was weighed and burned to an ash in a crucible. After an hour's burning over a Meeker burner the crucible was cooled and weighed. An ash, amounting to 5.1 per, cent by weight, was obtained. The original cloth is said to have an ash of less than 0.1 per cent.

Satisfactory material for imparting waterrepellency to mildew-proofed organic fibrous material can be prepared in accordance with the disclosure provided in the copending application for United States Letters Patent Serial No. 636,- 511 filed December 21, 1945, now abandoned, in the names of Howard D. Hartough and Sigmund J. Lukasiewicz. However, a material, preferred at this time for imparting water-repellency to mildew-proofed organic fibrous material, can be prepared by reacting thiophene or a derivative thereof as defined in the aforesaid copending application with formaldehyde or its polymers and ammonium halide in the presence of an acid having an ionization constant greater than 1 10- such as [HSOal-, (S02), (NaHSOs), acetic acid, arsenic acid, benzoic acid, haloalkanoic acid, citric acid, formic acid, fumaric acid, moleic acid, etc. (Table pages 1396-7, Langes Handbook of Chemistry, 5th Ed.) The $02, for example, may be added as the compound sulfur dioxide or may be present in the reaction mixture in the form of a soluble compound ionizing to give the radical [H803]: such as metal bisulfites. This method is described more fully in the copending application for United States Letters Patent Serial No. 781,754 filed in the names of John W. Schick and Howard D. Hartou h On October 23, 1947.

Illustrative of the method of preparing material preferred at this time for imparting waterrepellency to mildewproofed organic fibrous material is the following illustrative example taken from the aforementioned copending application' for United States Letters Patent Serial 170.781.754.

A mixture of about 84 parts by weight of thiophene (about one mole), about parts by weight of 37 per cent aqueous formaldehyde (about 1.2 moles), about 27 parts by weight of ammonium chloride (about 0.5 mole) and about 52 parts by weight of sodium bisulfite (about 0.5 mole), i. e. 1.0 mole equivalent ofHSOr or 0.5 mole sulfurous acid, was refluxed for about 5 hours. Upon cooling to ambient temperature a crystallinev precipitate formed which, when separated and recrystallized from hot water, gave a white crystalline product of the following analysis: sulfur, 18.6 per cent; nitrogen,-4.87 per cent In the description given hereinbefore of the present invention and in the claims hereinafter, the term fibrous material includes wool, cotton, linen, silk, rayon, nylon. hemp, jute and various artificial fibers of organic material in the form of threads, skeins or in woven form as well as paper, sheeted cellulose, leather, fur and the like. Thus, for example, fishing nets as such or the twine from which the nets are made "may be treated as described hereinbefore to provide a net which will'not absorb as much water as untreated nets and at the same time the nets will be resistant to attack by fungi and/or bacteria. Furthermore, the term "5-membered heterocyclic compounds" includes furan, pyrrole, thiophene and derivatives thereof having stable electropositive nuclear substituents other than unstable (OH)- and (NHz)- groups. In addi tion, the treatment with metal salts to mildewproof the fabric before imparting water-repellency can be modified to fire-retard the fibrous material before imparting water-repellency. That is to say, instead of or in addition to mildew-proofing the fibrous material, the fibrous material may be impregnated with any of the well known inorganic materials known to the art to impart resistance to fire and then treated to make the fibrous material water-repellent. Thus, the present invention includes such treatment as provides fibrous material associated with an inorganic salt and a nitrogenous resinous material having at least one 5-membered heterocyclic radical per polymer unit and particularly with nitrogenous resinous material having at least one S-membered heterocyclic radical having sulfur or oxygen as the heterocyclic atom per polymer unit.

We claim:

I. The method for producing mildew-proofed, water-repellent organic fibrous material, which comprises contacting organic fibrous material with a first aqueous solution containing about 5 to about weight per cent of copper acetate to sorb at least a portion of said copper salt on said fibrous material, separating said fibrous material and sorbed copper salt from said first aqueous solution, contacting the so-treated fibrous material with a second aqueous solution containing about 5 to about weight per cent of trisodium phosphate, thereby obtaining treated fibrous material having sorbed water insoluble copper salt, separating the so-treated fibrous material from said second aqueous solution, contacting the so-treated fibrous material with, a

third aqueous solution containing a water-soluble nitrogenous material, said nitrogenous material being obtained by reacting a heterocyclic compound selected from the group consisting of furan, pyrrole and thiophene with at least a molecular equivalent per mole of said heterocyclic compound of a nitrogenous compound selected from one group consisting of hydroxyl substituted ammonium halide and ammonium halide havin a molecular weight calculated as NHiX, where X is halogen, greater than 38 and with formaldehyde to obtain water-soluble nitrogenous material, thereby obtaining organic fibrous material with sorbed water-insoluble copper salt and sorbed water-soluble nitrogenous material, separating the so-treated fibrous material from said third aqueous solution, contacting the sotreated fibrous material with a fourth aqueous sodium acetateto convert said sorbed watersoluble nitrogenous material into sorbed waterlnsoluble nitrogenous material, separating the so-treated fibrous material from said fourth aqueous solution, water-washing the so-treated fibrous material, contacting the so-treated fibrous material with a fifth aqueous, alkaline solution containing formaldehyde, having a pH of about that of an aqueous solution containing 1% NaOH and 12% formaldehyde, separating the so-treated fibrous material from said fifth aqueous solution, heat-treating the so-treated fibrous material at about to about C.. and water-washing the so-trea'ted fibrous material whereby mildewproofed, water-repellent organic fibrous material is obtained.

2. The method for producing mildew-proofed, water-repellent organic fibrous material which comprises contacting organic fibrous material having sorbed water-insoluble inorganic copper compound selected from the group consisting of furan, pyrrole and thiophene with more than 0.25 mole per mole of heterocyclic compound of a nitrogenous compound selected from the group consisting of hydroxyl substituted ammonium halide andammonium halide having a molecular weight calculated as NH4X, where X is halogen,

greater than 38 and with formaldehyde, to obtain water-soluble nitrogenous material, thereby obtaining organic fibrous material having sorbed water-insoluble copper salt and sorbed water- .soluble nitrogenous material, separating the sotreated fibrous material from said first aqueous solution, contacting the so-treated fibrous material with a second aqueous solution containing sodium acetate to convert said sorbed watersoluble nitrogenous material into sorbed waterinsoluble nitrogenous material, separating the so-treated fibrous material from said second aqueous solution, water-washing the so-treated fibrous material, contacting the water-washed fibrous material with a third aqueous alkaline solution containing formaldehyde having a pH of about that of an aqueous solution containing 1% NaOH and 12% formaldehyde, separating the so-treated fibrous material from said third aqueous solution, heat treating the so-treated fibrous material at about 115 to about 120 C., and water-washing the so-treated fibrous material whereby mildew-proofed, water-repellent organic fibrous material is obtained.

3. The method for producing mildew-proofed, water-repellent organic fibrous material which comprises contacting organic fibrous material having sorbed'water-insoluble salt of a metal selected from the group consisting of copper, zinc and mercury, with a first aqueous solution containing water-soluble nitrogenous material to obtain/organic fibrous material having sorbed water-insoluble inorganic salt and sorbed watersoluble nitrogenous material, said nitrogenous material being obtained by reacting a heterocyclic compound selected from the group consisting of furan, pyrrole and thiophene with more than 0.25 mole per mole of heterocyclic compound of a nitrogenous compound selected from the group consisting of hydroxyl substituted ammonium chloride and ammonium chloride and with formaldehyde to obtain water-soluble nitrogenous material. contacting the so-treated fibrous material with an aqueous solution of a salt aacaoro water-repellent organic fibrous material which comprises contacting mildew-proofed organic fibrous material having sorbed water-insoluble salt of a metal selected from the group consisting of copper, zinc and mercury with a first aqueous solution containing a hydrohalide of a nitrogenous condensation product of thiophene to obtain organic fibrous material having said sorbed water-insoluble salt of said metal and sorbed hydrohalide, said hydrohalide of a nitrogenous condensation product of thiophene having been obtained by reacting thiophene, formaldehyde and more than 0.25 mole per mole of thiophene of an ammonium halide having a molecular weight greater than 38, contacting the so-treated fibrous material with a solution of sodium acetate to convert said sorbed water-soluble hydrohalide to sorbed water-insoluble nitrogenous condensation product, contacting the so-treated fibrous material with an aqueous solution of formaldehyde having about the pH of an aqueous solution containing 1% NaOH and 12% formaldehyde, heattreating at a temperature of about 115 to about 120 C. the so-treated fibrous material, and laundering the so-treated fibrous material whereby mildew-proofed, water-repellent organic fibrous material is obtained.

5. The method for producing mildew-mooted, water-repellent organic fibrous material which comprises contacting mildew-proofed organic fibrous material having sorbed copper phosphate with an aqueous solution containing a hydrochloride of a nitrogenous condensation product of thiophene to obtain mildew-proofed organic fibrous material having sorbed copper phosphate and sorbed hydrochloride of said nitrogenous condensation product of thiophene, said hydrochloride having been obtained by reacting thiophene, formaldehyde and more than 0.25 mole of ammonium chloride per mole of thiophene, contacting the so-treated organic fibrous material with an aqueous solution of sodium acetate to convert said sorbed water-soluble hydrochloride to a sorbed water-insoluble nitrogenous condensation product o1' thiophene. contacting thosetreated organic fibrous material with an aqueous solution containing about 1% NaOH and about 12% formaldehyde, heat-treating the so-treated organic fibrous material at about to about C. and laundering the so-treated organic fibrous material, whereby mildew-proofed, waterrepellent organic fibrous material is obtained.

. 6. Organic fibrous material having sorbed water-insoluble inorganic material selected from the group consisting of water-insoluble salts of copper. zinc and mercury inhibiting the growth of mildew and having sorbed nitrogenous resinous material suflicient to increase the water-repellency of said fibrous material, said nitrogenous resinous material having as its principal component the reaction product of formaldehyde, 9. material selected from the group consisting of furan, pyrrole and thiophene and at least 0.25 mole per mole of said heterocyclic compound of a material selected from the group consisting of hydroxyl substituted ammonium halide and ammonium halide having a molecular weight calculated at NHrX, where X is halogen, greater than 38.

7. Organic fibrous material having sorbed water-insoluble inorganic material selected from the group consisting of water-insoluble salts of copper. zinc and mercury and having sorbed nitrogenous, resinous material suflicient to increase the water-repellency of said fibrous material, said nitrogenous material having as its principal component, the reaction product of formaldehyde, thiophene and more than 0.25 mole of ammonium chloride per mole of thiophene.

PAUL V. KEYSER, JR. JOHN W. SCHICK. HOWARD D. HARTOUGH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'I'ENTS Number Name Date 2,043,137 White June 2, 1936 2,098,942 Brubaker Nov. 16, 1937 2,147,057 Platt et al Feb. 14, 1939 2,169,576 Booth et a1 Aug. 15, 1939 2,306,924 Zerweck et a1 Dec. 29, 1942 2,345,966 Fiedler et a1 Apr. 4, 1944 2,369,948 D'Alelio Feb. 20, 1945 2,381,863 Benignus Aug. 14, 1945 ,453,085 Caeser Nov. 2, 1948 2,453,086 Caeser Nov. 2, 1948

Claims (1)

1. THE METHOD FOR PRODUCING MILDEW-PROOFED, WATER-REPELLENT ORGANIC FIBROUS MATERIAL, WHICH COMPRISES CONTACTING ORGANIC FIBROUS MATERIAL WITH A FIRST AQUEOUS SOLUTION CONTAINING ABOUT 5 TO ABOUT 10 WEIGHT PER CENT OF COPPER ACETATE TO SORB AT LEAST A PORTION OF SAID COPPER SALT ON SAID FIBROUS MATERIAL, SEPARATING SAID FIBROUS MATERIAL AND SORBED COPPER SALT FROM SAID FIRST AQUEOUS SOLUTION, CONTACTING THE SO-TREATED FIBROUS MATERIAL WITH A SECOND AQUEOUS SOLUTION CONTAINING ABOUT 5 TO ABOUT 15 WEIGHT PER CENT OF TRISODIUM PHOSPHATE, THEREBY OBTAINING TREATED FIBROUS MATERIAL HAVING SORBED WATER INSOLUBLE COPPER SALT, SEPARATING THE SO-TREATED FIBROUS MATERIAL FROM SAID SECOND AQUEOUS SOLUTION, CONTACTING THE SO-TREATED FIBROUS MATERIAL WITH A THIRD AQUEOUS SOLUTION CONTAINING A WATER-SOLUBLE NITROGENOUS MATERIAL, SAID NITROGENOUS MATERIAL BEING OBTAINED BY REACTING A HETEROCYCLIC COMPOUND SELECTED FROM THE GROUP CONSISTING OF FURAN, PYRROLE AND THIOPHENE WITH AT LEAST A MOLECULAR EQUIVALENT PER MOLE OF SAID HETEROCYCLIC COMPOUND OF A NITROGENOUS COMPOUND SELECTED FROM ONE GROUP CONSISTING OF HYDROZYL SUBSTITUTED AMMONIUM HALIDE AND AMMONIUM HALIDE HAVING A MOLECULAR WEIGHT CALCULATED AS NH4X WHERE X IS HALOGEN, GREATER THAN 28 AND WITH FORMALDEHYDE TO OBTAIN WATER-SOLUBLE NITROGENOUS MATERIAL, THEREBY OBTAINING ORGANIC FIBROUS MATERIAL WITH SORBED WATER-INSOLUBLE COPPER SALT AND SORBED WATER-SOLUBLE NITROGENOUS MATERIAL SEPARATING THE SO-TREATED FIBROUS MATERIAL FROM SAID THIRD AQUEOUS SOLUTION, CONTACTING THE SOTREATED FIBROUS MATERIAL WITH A FOURTH AQUEOUS SOLUTION CONTAINING ABOUT 10 WEIGHT PER CENT SODIUM ACETATE TO CONVERT SAID SORBED WATERSOLUBLE NITROGENOUS MATERIAL INTO SORBED WATERINSOLUBLE NITROGENOUS MATERIAL, SEPARATING THE TREATED FIBROUS MATERIAL FROM SAID FOURTH AQUEOUS SOLUTION, WATER-WASHING THE SO-TREATED FIBROUS MATERIAL, CONTACTING THE SO-TREATED FIBROUS MATERIAL WITH A FIFTH AQUEOUS, ALKALINE SOLUTION CONTAINING FORM ALDEHYDE, HAVING A PH OF ABOUT THAT OF AN AQUEOUS SOLUTION CONTAINING 1% NAOH AND 12% FORMALDEHYDE, SEPARATING THE SO-TREATED FIBROUS MATERIAL FROM THE SAID FIFTH AQUEOUS SOLUTION, HEAT-TREATING THE SO-TREATED FIBROUS MATERIAL AT ABOUT 115* TO ABOUT 120* C., AND WATER-WASHING THE SO-TREATED FIBROUS MATERIAL WHEREBY MILDEWPROOFED, WATER-REPELLENT ORGANIC FIBROUS MATERIAL IS OBTAINED.