US2278417A - Treatment of cellulosic material - Google Patents

Description

Patented Apr. 7, 1942 TREATMENT OF GELLULOSIC MATERIAL Alfred William Baldwin, John Gwynant Evans,

and Charles Edward Salkeld, Blackley, Mancheater, England, assignors to Imperial Chemical Industries Limited, a corporation otfiireatv Britain No Drawing. Application December 1, 1936, Se riai.No.1l 3,702. In Great Britain June 8, 1936 1-4 Claims.

This invention relates to a treatment of'cellulosic materials, whereby they are given a permanent, finish and other improved properties.

We use the term cellulosic materialskto include which maybe normal or branched, -parafiinoid or ethylenoid; or it may be of a morecomplicated aliphatic hydrocarbon structure, as in the parent hydrocarbon of the naphthenic acids or their hydrogenation products; while-,R" stands It will When -N(tert) is when chlocottonand other cellulosicnatural fibres and regenerated cellulose-substances in the form of for hydrogen or a hydrocarbon radical.

fibre or film. Cellulosic'natural fibres include benoted that R-CO is an acyl radical, that is flax, jute, hemp, and sisal, wood pulpand other the radical of the acid of a fat or fatty oil, or the seed coat or best or other ve'getable structural radical of a phy lly Simil r acidfibrous matter. These and cotton are use'd'in the 10 Again, in the formula given above, -N(tert)- manufacture of yarn .and' knitted. and woven stands for a tertiary amine which is either fabrics, and for making paper and cardboard. heterocyclic or aliphatic.

The invention is applicable to the treatment of heterocyclic it is typified by pyridine, but picoline fibres in any stage of their manufacture. It is, or other pyridine homologue, or quinollne also however, particularly directed to the manufacl5 serve, or an N-alkyl-piperidine or N-benzylture of woven materials with improved properpiperidine or a C-homologue thereof; ties. When woven material or spun yarn is in N-(tert)- is aliphatic it is typified by triquestion, the invention is not limited ,to the m thylamine, but trimethyl ne. tributyl m ne. treatment of fabrics or yarns composed wholly trietha-nolamine a difllkylcyclohexylamine Will of the cellulosic material, but includes also a also serve. treatment of composite fabrics or yarns, for in- Finally in the for a given above X S ds stance, of union fabrics. for a monovalent acid group.

The improved properties conferred on the cela b t u de standing of the herein follulose materials after they have been treated aclowing disclosure, b WithOut y e t to limit cording to the invention may be collectively det ne natu of t s ti n. t foll wscribed as permanent water-repellent properties. ing typical compounds are mentioned as illus- In particular, woven fabrics may be so treated trative of the scop of u a I above! as to become water-repellent or showerproof, and Stearamido-methyl-pyridinium chloride: this finish is permanent, that is, it is unafiected or notseriously affected by exposure to the CHHB5 CONH CH2 N(C5H5) C1 weather, or by laundering, dry-cleaning, or other Steam-methylamido'methyl-pyridinium cleansing operations. Moreover, the handle of C19: the treated materials (i. e. yarns and fabrics) WHQPCI]TCH2N CH9C1 is soft. Byt appropriate modification, when nec- CHa essary, of he mode of treatment according to this invention, fabrics and yarns of varied soft gizf m methyl pyndimum hydrogen handle may be obtained. This softening efiect oleylamido methy1 pyridimum chloride;

15 hkewlse' of e and the corresponding trimethylammonium, tri- The process of th1s invention is applicable to ethanolammomu'm etc. sa1ts cellulosic materials whether or not they have 40 Incarrying the invention into practical effect been dyed. When, however, the materlals a the compound of Formula I above is dissolved or been dyed with certam dyestuffs substantive smpended in aqueous medium usually water towards cellulose, namely, those of the direct alone to give a dilute aqueous golution or cotton colour group, then another effect of the pension E5321???ititi foiif'ti iefiii?i difsfifg In genera h Operation of impregnating the of this, mu become fixed cellulosic material may be carried out preferably A g d1 th at a temperature below 40 C. especially when cemng o e we lmpregnate the dilute aqueous solutions (e. g. 0.1%) are used; said oellulosic materials with a quaternary amwith more concentr ted 1 1 monium compound of the general formula qu Ions hotter, even boiling solution may be applied.

RC z (D However, when kept at temperatures above 40 v R C. the solution may become acid; then a less sat as more fully defined below, which is applied isfactory finish, not so resistant to organic soifrom aqueous medium, and we then heat the so- Vents. is Obtainedimpregnated material to the decomposition tem- Thus with Woven Cotton fabrics, et at perature of said compound, preferably after preknown in the l as limblic, a dilute q eou vious drying, solution of the compound e. g. stearamiciomethyl- In the above general formula R is an aliphatic pyridinium chloride. may be e p e and the hydrocarbon radical of 10 or more carbon atoms U0 concentration may be as low as 0.05%. The fabric is padded in this solution, and squeezed. It then contains about its own weight of solution, and thus the amount of compound with which the fabric is impregnatedis about the same percentage of the weight of the cloth as the percentage strength of the solution. The padding is conveniently carried out at about 40 C. Higher temperatures are preferably avoided, as the compound used tends to decompose in hot aqueous solution. Thus, a 0.5% aqueous solution of stearamidomethyl-pyridinium chloride becomes useless if it has been kept at 60 C. for more. than two hours or at 80 C. for more than one hour. v

If desired, however,-other adjuvants, such as wetting agents, or buffering agents, may be added to the bath. Suitable wetting agents are the formaldehyde-naphthalene-sulphonic acid condensation products. Alkaline substances or especially substances that have a buffering action, may conveniently be added to assist in keepingthe solutions or suspensions neutral or at least not acid to avoid .tendering of the cellulosic material. I 7

Suitable such substances are pyridine, borax, disodium hydrogen phosphate or sodium acetate. Hexamethylene-tetramine also is a suitable adjuvant as it decomposes when heated to give ammonia.

The cellulosic material is passed through or dipped in this dilute aqueous bath, the mechanical handling being of course suited to the nature of the material.

After immersion in the aqueous solution the material is preferably but not necessarily dried. If a concentrated solution, even 0.5%, is used, it is not necessary to dry. The production of the desired efiects is dependent to some extent on the conditions of dryingand heating. Drying is preferably carried out at a relatively low temperature (hereinafter referred to as the drying temperature). The heating is' at a higher temperature (conveniently called the baking temperature).

The drying temperature is preferably low. It is kept low in order that there may be no premature decomposition of the salt. But temperature of is a less important factor than speed and other conditions of drying. Thus, for instance, a cotton fabric impregnated with an aqueous solution of stearamidomethylpyridinium, chloride and driedin more or less stagnant air, as in an oven without artificial circulation, should preferably be not submitted to a drying temperature of more than 30C. inasmuch as the higher the temperature at this stage the more the intensity of the ultimate water repellent effect tends to diminish. When, on the other hand, the impregnated material is dried in a brisk current of hot air so that the water is removed rapidly (in about 3 minutes) then the drying tempera:- ture may rise to 80 C. without disadvantage.

Again, if the wet material impregnated in a 1% aqueous solution is dried on a steam-heated cylinder at 120 C. for e. g. one minute, no waterrepellent efiect is obtained. on continuing the heating for five minutes, water-repellent properties are indeed conferred on the material, but the so-treated material is sensitive to the action of the solvents.

The baking treatment is essential for the pro duction of permanent water-repellent properties. The impregnated material begins to show waterrepellent properties after baking for ten minutes at 65 but the optimum effects are obtained when i baking is carried out at 90-120 0. Poor results are obtained at a higher temperature, e. g. 150' C.

The time of baking necessary to produce the desired finishes varies with the baking temperature and depends also on the nature of the impregnation reagent. The time of baking can be shortened at higher temperatures. For example using stearamidomethylpyridinium' chloride one must bake at 105 C. for five minutes, or at 120 C. for one-and-a-half minutes. The baking time should, of course. be kept at minimum to avoid damage to the fabric (tendering).

During the baking treatment there is decomposition of the salt which is made manifest when a pyridinium compound is used, by there being generated an odor of pyridine.

The following examples illustrate but do not limit the invention. The parts are by weight.

Example 1 Cotton sheeting is immersed for ten minutes at 20 C. in an impregnating bath consisting of a solution of five parts of stearamidomethylpyridinium chloride in 1000 parts of water. The impregnated material is then squeezed and dried by heating for ten minutes at 105 C. A fabric having a water-repellent finish and soft handle is obtained. The finish is resistant to dry-cleaning and laundering; V

Example 2 A viscose rayonfabric'is immersed for ten minutesat 20 'C. in a solution of five parts of stearamidomethylpyfldi'n'ium chloride in 1000 parts of water. The impregnated material is then squeezed and dried by heating at 105 C. for ten minutes. The resulting fabric'has a water-repellent finishand a soft handle which is resistant to dry cleaning and laundering.

E'zample 3 Example 4 Cotton sheeting is padded at room temperature in a solution containing one part of steeramidomethylpyridinium hydrogen sulphate and two parts of pyridine in 197 parts of water The material is squeezed to remove excess solution from the cloth and is then dried in a current of warm air at 30 C. It is then heated for 30 minutes in an oven at.105 C.

The finished material is highly water-repellent and has a pleasing soft handle. This waterrepellent softer finish is-very resistant .to laundering and dry-cleaning. I

- Example 5 Cotton sheeting which has been dyed to a 2% shade with Chlorazol Fast Red K (Colour Index No. 278) is padded at room temperature in a solution containing 1 part of palmitoamidomethylpyridinium chloride in 199 parts of water. The

material is squeezed and dried below 40 C. At this stage the shade of the dyeing is diflerent from that of untreated dyeing, being yellower in Example 6 Cotton sheeting is treated at 35 C. in a continuous padding operation, with a solutioncomtaining 1 part of 'stear'omidomethyl pyridinium chloride in 2000 parts of water. The material is squeezed, dried below 40 C. and is then heated for five minutes at 120 C. on a can drier.

The finish on the material is now soft and we.

ter-repeilent and is resistant to laundering and dry-cleaning.

Example 7 Cotton sheeting is treated at room temperature with a solution containing 1 part of stearamidomethyl pyridinfum chloride in 199 parts of water.

The material is squeezed, dried at a temperature Example 8 1 part of stearamidomethylpyridinium sulphite (which may be preparedin the manner described below) is dissolved in 99 parts of water at room temperature. Cotton sheeting is then padded with this solution, squeezed and dried in warm air (30 C.). The dried fabric is then heated for minutes at 105 C. The resulting fabric has a water-repellent, soft finish, which is resistant to dry; cleaning and laundering.

The stearamidomethylpyridinium sulphite used in the above example may be prepared as follows: parts by weight of steal-amide, 120 parts by weight of pyridine and 12 parts by weight of paraformaldehyde are stirred together at 90-100 C. Gaseous sulphur dioxide is passed into the heated mixture until a test sample of the mixture dissolves; to a clear solution in water. Pyridine and unreacted paraformaldehyde are then evaporated from the reaction mixture by heating at -50 C. under reduced pressure, for example, 15 mm. The desired product is thus obtained as a viscous mass which may be further purified, if desired, by washing with acetone.

In a manner similar to the above examples other compounds following the generic formula above indicated may be used for the purposes of this invention, Among the numerous compounds actually tried by the following may. be mentioned- In place of the fatty acids thus referred to,

(made others may be used. Thus, the starting out materials may be the fatty acids of palm oil, cotton seed oil, taliow, or derived acids such as those obtained by the processes of fat hydrogenation.

Some of the said compounds are made by bringing together a hydroxymethylamide of a fatty acid and a tertiary amine salt or an addition compound of a tertiary amine and an inorganic acid anhydride: for example, stearohydroxymethylamide (made from stearamide and paraformaldehyde) is treated with pyradine hydrochloride in pyridine; or stearamide, paraformaldehyde, and anhydrous pyridine hydrochloride, nitrate, m-nitrobenzene-sulfonate or the like are caused to react together in pyridine solution; or stearomethylamide, formaldehyde and hydrogen chloride arecaused to interact to give stearomethylamide methyl chloride, which is then combined with pyridine orother tertiary amine.

Instead .of pyridine in the lastmentioned synthesis, trimethylamine or triethanolamine may be used.

Methods of making some of the compounds the use of which is contemplated in the invention are the subject of British Patents Nos. 4'71,- 130 and 475,170, and the corresponding U. S. Patents Nos. 2,131,362 and 2,146,392.

It will be'understood that the above examples are merely illustrative, and that the details of procedure may be varied within wide limits, without departing from the spirit of this invention. For instance, the temperature of the baking treatment may vary from C. to 200 0., the duration of the treatment being conveniently adjusted so as to avoid undue injury to the fibre. In practice the time of the baking-treatment may vary from a few seconds to one hour.

Likewise the drying treatment may vary as to time and temperature as already indicated above. v

The concentration of the treating agent in the aqueous solution may vary from 0.01% to 2% or even higher if desired. The quantity of the agent applied with respect to the weight of fibre treated may be "so chosen by controlling the amount of solution left upon the fibre after the ,by the interaction between a tertiary organic nitrogenous base and a higher aliphatic amide of the general formula wherein R is an aliphatic hydrocarbon radical containing at least 10 carbon atoms, R" is a member of the group consisting of hydrogen and hydrocarbon radicals, while X is the anion of a salt-forming acid.

2. A process for imparting to cellulosic material durable water-repellent properties, which comprises impregnating said material with a quaternary ammonium compound of the general formula RC O-N-CHZN (tert)X wherein the group RCO- represents the acyl radical of a fatty acid having not less than 11 carbon atoms, R" stands for a member of the group consisting of hydrogen and hydrocarbon radicals, N(tert) stands for the radical of a terdrive of! moisture and then to cause decomposition of said quaternary ammonium compound, liberating the free tertiary base.

3. Cellulosic textile material impregnated with a surface improving agent according to the process defined in claim 2.

4. A process as claimed in claim 2 wherein the cellulosic material is padded in an aqueous solution, dried at a low temperature, and then baked at a temperature not less than 100 C.

5. A process as in claim 2, the impregnation being effected from aqueous bath and the latter containing further a substance having a buffering action to assist in keeping down the acidity of the medium surrounding the fiber during the heat treatment.

6. A process as in claim 2, the impregnation being eifected from aqueous bath and the latter containing sodium acetate.

'7. A process for rendering cellulose textile material water-repellent which comprises impregnating the material with a quaternary ammonium compound of .the formula o R-gNHCHz-NX-'Halogen in which R stands for an aliphaticradlcal containing at least ten carbon atoms and NK for a tertiary amine, and then heating the impregnated material in the .absence of moisture at a temperature sufficient to decompose the quaternary ammonium compound with the liberation of the free amine.

8. Cellulosic material impregnated with a surface improving reagent as defined by the process and compounds defined in claim 7.

9. The process of treating cellulosic material whereby to impart thereto improved surface characteristics which comprises impregnating the same with a quaternary compound of the general formula R-CO-NHCH2N(aliph)X, wherein Ris an aliphatic radical having not less than carbon atoms and attached to the CO group above through one of its own carbon atoms; N (aliph) stands for the molecule of a tertiary aliphatic amine, while X is the anion of an ionizable acid; and heating said material in the absence of moisture at a temperature sufficient to decompose the quaternary ammonium compound with the liberation of the free amine. 10. The process of treating 'cellulosic material whereby to impart thereto improved surface characteristics which comprises impregnating the same with a quaternary compound of the general formula wherein R is an aliphatic radical having not less than 10 carbon atoms and attached to the CO group above through one of its own carbon atoms, while X is the anion of an ionizable acid, and heating said material in the absence of moisture at a temperature sufficient to decompose said quaternary compound as evidenced by the liberation of free pyridine.

11. A process for rendering cellulose textile material water-repellent which comprises impregnating the material with stearamidomethylene pyridinium chloride, then drying and heating the impregnated material at a temperature suflicient to decompose the compound as evidenced by the liberation of free pyridine.

12. Cellulosic textile material impregnated according to claim 11, said textile material being characterized by having water-repellent properties and a soft feel as compared to the untreated material, which properties are fast to laundering.

13. The process of treating cellulosic textile fabric whereby to impart thereto water-repellent surface characteristics, which comprises treating the same with an aqueous solution of stearamidomethylene pyridinium chloride at a temperature not exceeding 40' C., drying said material at a temperature not exceeding 40 C. and then heat ing the dried material in the absence of moisture at a temperature between and C.

14. A process as in claim 11 modified to this extent, that the drying step is merged into the subsequent heating step the combined treatment being effected at a temperature of between 90 and C.

ALFRED WILLIAM BALDWIN. JOHN GWYNANT EVANS. CHARLES EDWARD SALKELD.