US2367273A - Treatment of wool - Google Patents

Description

Patented Jan. 16, 1945 TREATMENT OF wooL I Archibald John Hall and Frederick Charles Wood,

Manchester, England, assignors to Tootal Broadhurst Lee Company Limited, Manchester, England, a British company No Drawing. Application October 24, 1940, Serial No. 362,694. In Great Britain October 30, 1939 14 Claims.

This invention is primarily concerned with the treatment of wool, though it may also be applied to the treatment of other materials, especially textile materials. The reagent used for the purpose is believed to be novel. I

The invention is thus particularly concerned with the treatment, in whole or in part, of materials consisting wholly or partly of wool'to reduce or substantially eliminate their usual tendency to felt when washed in aqueous liquors. The wool may be in the form of loose fibres or in a manufactured form such as yarn and fabric which may have received some treatment such as scouring, bleaching, dyeing, hot pressing'and milling.

The term wool" includes all animal fibres which are capable of being felted.

In describing this invention, the term felt" is to be understood to refer to that property of ordinary wool which causes the individual fibres to close upon each other in washing, or other treatment in aqueous liquor in which the wool material is repeatedly squeezed and rubbed, so that the wool material becomes denser and more compact. This property of felting is responsible for the shrinkage which wool yarns and fabrics suffer when washed, so that such materials may be made'less shrinkable by treating them according to this invention.

Materials containing wool which have alreadybeen partially felted may be prevented from further felting by the process herein described.

According to the present invention, the wool or other material is treated with a reagent containing little or no water comprising (a) an alkallne substance; (b) an organic solvent for (a) and (c) an organic liquid which is a non-solvent or poor solvent for (a) and miscible with the solution of (a) in (b). Preferably the non-solvent is in large excess. After such treatment it is desirable to remove or otherwise render innocuous unchanged alkali and medium and the decomposition products to an extent such that the wool will not deteriorate during subsequent storage.

The term alkaline substance is defined herein as a substance which in presence of water, would give hydroxyl ions, and includes alkalies or organic bases or substances producing or capable of producing an alkali or organic base, preferably of stronger basic nature than ammonia.

The preferred alkaline substances are those (of stronger basic naturethan ammonia) which,

in the presence of a suitable amount of moisture may exert a gelatinizing action on wool and may to some degree produce chemical changes or decomposition of the wool. Among. those found effective are organic ammonium, sulphonium and iodonium hydroxides such as benzyltrimethyl ammonium hydroxide; tertiary amine oxides; by-

' liquids which in absence of the alkaline substance would be chemically inert or relatively inert to wool or other material undergoing treatment.

The organic solvent (which term includes a single liquid or a mixture of liquids) is chosen with relation to the alkaline substance. Suitable solvents may be found among the aliphatic alcohols especially those containing three to eight carbon atoms, but also oleyl, stearyl, ricinoleyl, or aromatic alcohols such as benzyl alcohol or phenyl ethyl alcohol, hydroaromatic alcohols such as cyclohexanol, amino alcohols or glycol vethers such as ethylene glycol, acetone, ethylacetoacetate, aniline, ethyl acetate or amyl acetate.

In treating wool, alcohols containing 3-8 carbon atoms are preferred as compared with methyl or ethyl alcohol. Preferably the flash point of the mixture of solvent and non-solvent is above 60 F'. (Abel test). Mixtures of white spirit of flash point 92 F. with only 2% of ethyl alcohol show a flash point of F. whereas the addition of 2% of n-butyl alcohol merely reduces the flash point to 82 F.

The non-solvent or poor solvent (which term includes a single liquid or a mixture of liquids) is preferably a hydrocarbon such as a petroleum distillate, e. g. paraffin, hexane, white spirit (a petroleum distillate of boiling range 150-260 C. and sp. g. 0.81), or petrol or chlorinated hydrocarbon or an aromatic or hydroaromatic hydrocarbon such as toluene o'r tetrahydronaphthalene, but other non-solvents and poor solvents such as pyridine, ketones, ethers or esters or higher alcohols may be used.

These'non-solvents and poor solvents act as In certain cases the diluent may consist of a good solvent for (a) suitably diluted with a nonsolvent or poor solvent. The desirable property of a diluent to give a uniform treatment is that it can be addedto and be perfectly miscible with a solution of the type (a) in (b) so as to yield a solution or uniform dispersion containing an amount of alkali capable of acting on the wool or other material to the extent desired.

We have found the reagents according to the invention are generally less harmful to the wool as regards lowering its quality and are more efthe methyl, ethyl and butyl ethers of fective in reducing its felting power than solu--' tions of alkalies without diluents. Our reagents are similarly more satisfactory when they contain a higher proportion of the diluent and a. lower proportion of the solvent. We prefer to use reagents which contain the highest propor. tion ofdiluent consistent with the alkali remain ing in solution. It is believed that the presence of the diluent is beneficial. partly because, owing to its non-solvent properties, it tends to force the alkali from the solution onto the wool.

It is believed, although this does not limit this Invention in any way, that the action of the alkaline treatment is mainly confined to the surface of such wool fibre, and that any substantial extension of this action to the interior of the ilbre adversely aflfects its quality. The term quality" is here to be understood to refer to a number of properties of the wool, such as tensile strength, softness of handle, colour and durability, which have to be taken into account in assessng the value and usefulness of a wool material. In general, the quality is reduced if the wool loses :1 weight and is made weaken-harsher, yellower and less durable.

It has been observed that under certain condi- ;ions of carrying out this invention, the wool may act only have its felting power decreased, but it nay also suffer changes which reduce its original uality. It is therefore necessary to arrange coniitions of treatment which will produce the re mired decrease of felting power accompanied of reagents containing appreciable amoimts of 2y any other change in the quality of the wool which is permissible or desired for the purpose in dew.

In carrying out this invention, adequate conrol-of the results obtained is possible because the :onditions of treatment of the wool may be varied videly. It has been found that the quality and he decrease of felting power of the treated wool :an be controlled by varying:

1) The composition of the reagent as regards its content of one or more of the alizalies and one or more of the solvents and poor ittention must be given to all these conditions f treatment of the wool in order to obtain the esult desired.

We prefer to use reagents which contain little r no water, but it is important to note that this ondition refers to the reagent and not to the pol under treatment. Some water may be presnt arising from direct addition or its presence my be adventitious arising from difficulties of btaining completely water-free ingredients of ie reagent or preventing the entrance of water uring the preparation of --the reagent. Many of ie reagents used, particularly those containing large proportion of ahydrocarbon or other oranic solvent not containing a hydroxyl group DH), are almost immiscible with water. The :agents used in this invention are preferably lose which contain not more than about 2% of ater (by volume) but they may contain quanties up to the limit of its solubility in the rerent.

water is generally harmful in that the quality of the wool is lowered. This may be corrected to a certain extent by decreasing the time of action or otherwise adjusting the conditions of the treatment. Wool harmed by such treatment usually has a pronounced yellow colour which may be accompanied by an impoverished handle, loss of weight and appearance.

The effect on the resultingdecrease of felting power of the wool produced by adding water to the reagent varies considerably according to the composition of the reagent.

The moisture content of the wool when treated with the reagent influences both the reduction or felting power and the lowering of quality of the wool so that ,this moisture content may be varied widely according to the results which aredesired. In general, wetting of the wool with waterbefore treatment promotes a lowering of the quality of the treated wool. But to some extent, this harmful action may be counteracted by reducing the duration of the treatment, and otherwise adjusting the conditions of the treatment.v But even when these adjustments are made, the treated wool is generally less satisfactory than when it is treated in an air-dry state. On the other hand, wool which is completely free from moisture is less reactive to the alkali treatment.

We have found that wool can be made nearly non-felting without appreciable loss of by treating it with the reagent when the wool contains 12-18% of water, and these conditions i are preferred.

Generally, the action of this alkali-treatment on wool with a given moisture content increases withincrease of temperature and with increase of *duration of treatment. At temperatures below ods of carrying out the invention involving the use of reagents having constituents which are gaseous at ordinary temperature and pressure (e. g. butadiene) increased pressure is desirable.

These volatile constituents may then be largely removed at the required time merely by releasing the pressure.

Conditions may also be arranged so that the her in which such conditions such as composition of the reagent, temperature and duration of treatment, and the moisture content of the wool at the time of its treatment, effect the results obtained, it will be understood that these condn has been observed that the acti n on W001 tions can be much varied and that similar results can be obtained bydifferent sets of conditions.

For the production of any particular dzrzired result, it may be necessary to make a few simple trials to ascertain the most suitable conditions of treatment to be used.

The treatment of wool with these reagents may quality,

produced. Thus the wool may be led through the reagent, then squeezed to remove loosely adhering solution, and allowed to lie at room temperature for a sufiicient period to obtain the result desired.

Alternatively, and this is one of the preferred methods, the wool may be steeped in the reagent until the desired effect is obtained, and then excess liquor removed by any suitable method such as centrifuging. It is found that a weaker alkalisolution may be used when the wool is treated so that it remains in contact for a considerable period with a relatively large volume of it than when the wool is rapidly impregnated with a relatively small volume of the liquor and then allowed to lie at room temperature for completion of the action, but the increase of alkali concentration required in the last named impregnation method may be reduced by allowing the impregnated wool to lie at a relatively high temperature, say 50 to 100 C. or even higher.

After the wool has remained in contact with the alkali solution under suitable conditions to obtain the desired reduction of its felting power, the alkali inthe wool should be removed by thorough washing with water which may be followed by treatment with an acid or by direct acid treatment followed by washing. In the former case care must be taken to avoid damage to the wool which may result from allowing it to be in contact with a high concentration of aqueous alkali. Alternatively the base in the wool is combined with substances so as to form products in or on the wool which have useful softening, lubricating or other efiects; high molecular weight acids such as oleic acid or oleyl hydrogen sulphate may be used for this purpose.

Neutralisation in the absence of water may be carried out by treating the alkaline wool with acid gases or vapour or with a'solution of an acid in an organic solvent. v

Although it is believed that this invention will be largely used for the all-over treatment oi materials consisting entirely or in part of wool for the purpose of rendering them non-felting, it is to be understood that it may also be used for treating such materials in selected parts or areas for the production of special effects. For example, the reagent may be applied to a woven wool fabric by textile printing methods or otherwise'to produce a striped or other pattern so that when the fabric is afterwards washed it will felt to a less degree in the treated parts. a

This invention is especially useful for the treatment pf wool mixed with fibres such as those of cotton and viscose rayon, since the alkali has no adverse action on these fibres. Other fibres which may be present with the wool are for example nylon, linen, rubber threads as for instance those used in elastic belts and garters of woollen goods, etc.

For determination of shrinkage in washing in these examples the following method may be used.

A portion of the fabric is first steeped in water and then dried free from tension. A square of cm. side is then marked on this relaxed fabric. The fabric is then washed (together with other fabrics for comparison when so desired) by hand with repeated squeezing in a /2% soap solution at SID-40 C. for a desired period, say 10 mins. The fabric is then rinsed in water, and dried free from tension. The marked square is then measured and the resulting contraction of area calculated and considered to be the area shrinkage.

The following examples illustrate the treatment of wool:

Two dozen pairs of men's wool socks weighing 8% lbs. were first scoured and lightly milled in a warm soap liquor, washed, dried, conditioned so as to contain 12.5% of moisture, and then steeped for 1 hour in 6.! gallons (British gallons) of a liquor initially at 17% C. and prepared by adding 6 gallons of kerosene to 0.7 gallon of a solution of caustic soda in normal butyl alcohol having a composition of 6 lbs, of caustic soda per 10 gallons 0! n-butyl alcohol. The socks were then withdrawn, centrifuged so that they contained not more than 0.15 gallon 01 residual liquor, and plunged into 8 gallons 01 cold water containing 0.2 gallon of sulphuric acid (sp. gr. 1.8) to neutralise the alkali in the wool. Thereafter the socks wer thoroughly washed and dried when they were found to have considerable resistance to felting.

It was noted that no rise in temperature oi the reagent occurred during the treatment of the socks.

. Example I! Solutions of caustic soda were made in normal butyl alcohol, glycol monoethyl ether and absolute ethyl alcohol, of concentrations shown in the table, column 1. The use of these solutions in alcohols is part of our Ser. No. 362,695, filed 0ctober 2d, lied.

Col- Column 1 Column 2 Column 8 ohm Area Composition oi solution Stock solution used in treatment oi x2 3 5253 3g the wool washing 1 volume stock solution For Normal butyl alcoplus cent hol-caustlc soda. 9 volumes butyl alcohol. 7 A 6.4 g. NaOH in Y cc. solution. 1 volume stock solution P 0.3 X 9 volumes white spirit. A

1 volume stock solution Glvcol monoethyl plus a 25 B other-caustic 22 vols. glycol monoa soda. 14g.NeOH ethyl ether. '5 in 100 cc. solution. 1 volume stock solution 8 p 5 1.6 Y 22 vols. white spirit. :1 O 1 volume stock solution E Absolute ethyl alglue as 16.6 C

cohol-caustic 9 vols. et yl alcohol. t? it it E s cc.- somflon- 1 volume solution 12. 6 Z

9 vols. w ite spirit.

Untreated fabric 34 U From these stock solution more dilute solutions were made by dilution with the alcohols concerned, or, according to the present invention, with white spirit, as shown in column 2. Samples 'of wool fabric conditioned over saturated brine were immersed in these solutions (column 2) for one hour at 20 C. The samples were then removed, centrlfuged, plunged into acidulated ficial effects in respect of resistance to shrinkage and felting'which are obtained when the impregnating solution contains a preponderating amount of the non-solvent for the alkali (e. g. white spirit) and particularly when the higher alcohols are used as solvents for the caustic alkali.

Example III 0.5 cc. water was added to 10 cos. of a caustic soda-butyl .alcohol solution (containing '7 gm. NaOH in 100 ccs. butyl alcohol) and then this was made up to 100 ccs. by addition of white spirit.

A knitted wool fabric was immersed in this at ordinary temperature for 15 minutes. It was then taken out and mangled, plunged into dilute acid and well washed successively in water and soap solutions.

A comparative test with an untreated fabric showed that on vigorous washing and rubbing the blank sample shrank 41.5% in area while the treated only shrank 12.5% in area. The treated.

sample had also resisted felting.

Example IV A sample of. knitted woolen fabric was completely dried in a hot oven and then put in a closed vesse1 containing methyl alcohol and its vapour. After some hours it was plunged into the following ternary mixture at 45 0.: one volume of caustic soda+butyl alcohol (6 g. NaOH per 100 ccs. mix-.

ture), diluted with 9- volumes of white spirit. After 2 minutes immersion the Wool was taken out, squeezed between rollers and the alkali im mediately neutralized with aqueous acid and the sample washed successively in water and soap solutions. A comparative washing test of this treated sample with an untreated sample showed reduced felting and shrinking properties.

Example V scoured knitted wool fabric containing rubber threads covered with cotton was steeped for one hour in a liquor initially at, 16 C. and prepared by diluting 10 cc. of a 6% solution of caustic soda in n-butyl alcohol with 90 cc. of white spirit. The fabric was then centrifuged, acidified with dilute sulphuric acid, thoroughly washed and dried. The resulting fabric had excellent resistance to felting and the rubber threads were not appreciably affected by the treatment.

The following examples illustrate variations in alkaline substance: I

Example VI A mixture of normal butyl alcohol and white area shrinkages for the treated and untreated fabrics were and 44% respectively.

Example VII 5 grams 'of air dry knitted wool fabric were immersed for hour in a liquor at 30-40 C. consisting of 30 ccs. of ethylene diamine, 2.5 ccs. of

white spirit and 15 cos. of butyl alcohol. The fabric was then mangled, acidified with dilute hydrochloric acid, washed and dried, when it was found to havevery good resistance to felting.

Example VIII A wool fabric was thoroughly wetted with water and-squeezed'ofi by passing through the nipping rollers of a mangle adjusted so that the fabric after mangling contained its own weight of water.

The fabric was then immersed in a solution containing '70 cc. of white spirit and 0.9 g. of metallic sodium dissolved in 30 cc. butyl alcohol.

After 3 mins. the material was mangled so as to remove excess liquor, washed, soured with acid to'neutralise any excess alkali and washed in soap.

The fabric had a much reduced tendency to felt during washing with warm soap solution after its treatment.

Similar results were obtained by using the same reagent for a longer period of time to treat wool fabrics containing 14% and 6% of moisture respectively.

Example IX A solution of caustic soda was made in normal butyl alcohol so as to contain 6 gm. NaOI-I in 100 cc. solution.

This was then diluted with five times its volume of White spirit so as to contain 1 gm. NaOH in 100 cc. mixture; CO2 gas was blown through 100 cc. of this solution until it was saturated. A gelatinous emulsion was formed in this process, to which another 100 ccs. of the original uncarbonated solution (-1 gram NaOI-I in 100 cc. butyl alcohol+white spirit) was added and the resulting dispersion thoroughly shaken.

A number of samples of conditioned knitted wool (conditioned over saturated brine) were immersed in this dispersionat temperatures maintained at 20 C., 40 C., and C., for varying periods of time from 2 hours to 16 hours at 20 0.; 15 mins. to 4 hours at 40 C. and 1 and 2 hours at 60 C.

After the prescribed periods of time had elapsed the wool samples were centrifuged to remove excess liquor and plunged into acidulated water, rinsed in dilute ammonia, rinsed again and finally soaped lightly to remove solvent, rinsed and dried.

All those samples treated at the same temperature, together with a control untreated sample, were subjected to a drastic washing and felting treatmentin soap solution with mechanical action.

All the treated samples showed remarkable resistance to shrinking and felting as compared with the untreated sample. One set of area shrinkage figures obtained are given in the following table:

Time of immersion (in ou t- Percent 2 38 to felting.

- then taken out, squeezed through rollers and plunged into dilute acid and finished in the usual way. It was found to possess increased resistance Example XI An amount of sodamide was reacted with excess of aniline in a stream of coal gas passing through the apparatus so as to produce a concentration of sodiophenylamine equivalent to 0.7 g. NaOH per 100 ccs. mixture. This solution of sodiophenylamine in aniline was diluted 7-fold with dichlorethylene so as to give a mixtur of sodiophenylamine in aniline and dichlorethylene. The concentration of sodiophenylamine in this diluted solution was equivalent to0.1 gm. NaOH per 100 ccs. mixture. A piece of knitted woollen fabric was immersed in thissolution at room temperature for 24 hours. It was then mangled and plunged into dilute HCl and well washed in water and given a light soapin followed by drying. This treated sample showed-a reduced tendency to felt and shrink.

, Example XII 1 A solution of caustic potash was made in absolute ethanol (ethyl alcohol) containing 6 g. of

XOR in 100 cc. solution. 10 cos. of this solution was diluted with 90 cos. of white spiritgiving a solution containing 0.6 g. KOH in 100 '00s. A sample of knitted woollen fabric weighing 7 grams was immersed in this solution for 1 hour at 18 C. It was then removed, mangled, and plunged into dilute acid. It was then washed in-water, washed again in soap solution and finally in water. The sample was dried and showed a much increased resistance to felting when washed together with an untreated sample.

The following examples illustrate variations in solvent (see also Examples m and Example XIII A solution of 5 gm. sodium peroxide was cautiously made in 100 cc. butyl alcohol. When no further oxygen came ofl, 85 ccs. of this was di-' luted to 600 cc. with white spirit. The concentration of NaOI-lin the butyl alcohol-l-white spirit mixture was thus about 0.7 gm. per 100 cc.

118 gm. of a woven wool fabric was immersed in the solution till it was wetted with the liquid and then run through squeezing rollers. The weight of the impregnated cloth was 215 gm.- corresponding with a liquor content of 82%. After 20 minutes the fabric was passed through water anda soap bath, washed and soured and finall dried. The fabric had much reduced felting power.

Example XIV All fasa atsvs 5 If wool is treated with the above mixture for one hour at ordinary room temperature a greater decrease of the felting-power of the wool is obtained than when a binary mixture of NaOH and methyl alcohol is used under similar conditions.

EzrampleXV Solid caustic soda was warmed with ricinoleyl alcohol and 10 ccs. of the warm liquid poured of! and mixed with a mixture of 10 cos. of ricinoleyl alcohol, 20 ccs. of dichlorethylene and 70 cos. of white spirit, thereby giving 110 cos. of a potentially alkaline solution equivalent to 0.4 g. NaOH- per ccs. solution. Air-dry wool samples were.

immersed in suitable volumes of this solution for l-d hours, squeezed, then acidified, washed free from solvent, and dried. The samples showed resistance to felting and shrinking. Y

' Example XVI A solution of caustic soda was made in the coldin phenylethyl alcohol (CsHr.CH2.CH2-OH) with excess of solid NaOH present and the liquids poured off. This was diluted with white spirit and the final analysis showed it contained 0.34 g.

of NaOH per 100 cos. of mixture. Air-dried knitted woollen fabric wa immersed in this solution for 24 hours at ordinary temperature, squeezed, neutralized, washed and dried. A washing test showed the treated sample to be resistant to felting and shrinking.

The following examples illustrate a variation in non-solvent and poor solvent (see also Examples m, XIV, XV)

Example XVII A solution of caustic soda. in n-butyl alcohol (6 grams NaOH in 100 ccs.) was diluted with 9 times its volume of carbon tetrachloride and conditioned wool fabric was then treated with this solution (ratio liquor to cloth=8/l) for 1 hour at 20 C. The fabric was then acidified, washed and dried and then found to possess excellent resistance tofelting and shrinking.

Wool may also be treated to have its felting power reduced with liquors prepared b treating gents include esters, ethers, fats, hydroxylic compounds, and may if desired be in the form of moulded articles, sheets, tubes, fibers, yarns and fabrics made from these and the treatment may becarried out so as to produce a partial modification or complete modification of the particular substance or material which is being subjected to the treatment.

The material to be treated may contain-a nonreactive part in addition to a reactive or partially reactive part or both, and hence a partial or com-- plem separation of component parts may be facilitated.

In the case of 'a partial conversion of materials to other materials either the unchanged portion or the portion which has undergone conversion may if desired be simultaneousl or afterwards removed by well known processes.

Exampl XVIII Normal butyl alcohol was shaken in a machine,

with solid caustic soda till a solution-emulsion was obtained. This was poured ofi from the solid caustic soda and analyzed.

The solution-emulsion was found to contain 15.4 gms. NaOH in 100 ccs. (88 gms.)

To 1%; litres of this solution-emulsion, 2.25 litres of normal butyl alcohol was added giving 3.75 litres of a clear solution of caustic soda in butyl alcohol containing about 64 gm. NaOH per litre.

One litre of this solution was diluted to litres with white spirit." A clear solution was obtained thus containing 6.4 gm. NaOH per litre.

This solution has the interesting property of giving a fine dispersion containing caustic soda when warmed, which redissolves on cooling. This property may be utilized in treating materials with the reagent.

The reagent may, for example, be used for the following purposes:

(1) The reduction of the acyl content of cellulose esters such as cellulose acetates, propionates, etc.- or hydrolization of other derivatives of cellulose, e. g. cellulose fibres, which have been and. starch, and dried. The fabric was then treated as described in Example XIX whereby it became dyed only in the non-printed part to give a white spot pattern on a blue or other coloured ground.

Example XXI One part of damp (not wet) plain bleached cotton fabric was immersed for one hour'at'room temperature in a solution consisting of 0.2 part (4) The transformation of ethyl acetate into ethyl acetoacetate.

(5) The cleaning of greasy metal and other materials, also the dry cleaning of textiles.

(6) The removal of carbon dioxide from gases by bubbling through the reagent.

(7) The treatment of cotton, regenerated cellulose, or silk fibres to effect a superficial swelling. This makes the fibres superficially reactive after which they may be subjected to other treatments.

This list is not exhaustive. The following examples illustrate some of these aspects of the invention.

Example XIX Example XX Cellulose acetate woven fabric was printed to give a spot pattern with a resist paste consisting of tartaric acid thickened with British gum ,ment is from 1-24 hours.

of caustic soda, 8 parts of butyl alcohol, and 92 parts of white spirit, and then mangled and immersed for five minutes at room temperature in a solution consisting of 5 parts of sulphuryl chloride in 100 parts of white spirit. The fabric was then mangled and thoroughly washed with dilute aqueous ammonia, then washed with water, and dried. The resulting fabric had a more sheer appearance and was stiffer as though it had been partly parchmentized.

The products according to the invention diifer from non-felting wool prepared by treatment with chlorine or chlorine compounds in that they,

usually acquire a stiffer and fuller handle when wetted in slightly alkaline liquor but that on drying they lose this increased stiffness and fullness so as to regain their original handle. This char.- acteristic of the wet product is in marked contrast to the thinner slippery handle of wool processed with chlorine or chlorine compounds.

In the specification, the term dispersions" includes solutions, suspensions or emulsions.

A preferred concentration of alkaline substance, is less than 1 gram NaOH (or an equivalent amount of another alkaline substance) and preferably from about 0.2 to 0.7 gram NaOH (or an equivalent amount of another alkaline substance) per 100 cc. dispersion. A preferred time of treat- A preferred temperature of treatment is l0-50 or more usually 12-30 C. The diluent preferably forms a major proportion of the dispersion, e. g. over and often over 75% by volume.

We declare that what we claim is:

1. A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of an alkaline substance having a stronger basic nature than ammonia, a liquid organic solvent for the alkaline substance, and an organic diluent liquid which is a poor solvent for the alkaline substance but is miscible with the solution of the alkaline substance in said organic solvent to give a stable dispersion.

2. A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent consisting essentially of an alkaline substance having a stronger basic nature than ammonia and dispersed in a major proportion of a diluent hydrocarbon by the aid of a minor proportion of analcoholic solvent of said are line substance, said solvent being miscible with the hydrocarbon, the maximum content of water in said reagent being not more thansubstantially 2 percent.

3. A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of a caustic alkali havinga stronger basic nature than ammonia, an alcohol effective as a solvent for the alkali, and a petroleum distillate which is a poor solvent [or the alkali but is miscible with the alcohol solution of the alkali to give a stable dispersion.

a. A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of caustic soda, butyl alcohol, and a volatile petroleum distillate which is a poor solvent for the alkali but is miscible with the solution of the alkali substance in said butyl alcohol to give a dispersion.

5. A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent consisting essentially of an alkaline substance having a stronger basic nature than ammonia, a liquid organic solvent for the alkaline substance, and an organic liquid which is a poor solvent for the alkaline substance but is miscible with the solution of the alkaline substance in said organic solvent to give a dispersion, said reagent containing not more than substantially 2 percent of water; removing the treated wool from the reagent, and neutralizing the residual alkaline substance present in the wool in the substantial absence of water.

6. A process of reducing the tendency of wool to felt, which comprises treating the wool for 1 to 20 hours at a temperature of to 50 degrees C. with a reagent containing not more than substantially two percent of water and consisting essentially of an alkaline substance having a stronger basic nature than ammonia and dispersed in a liquid comprising at least '75 percent of an organic diluent liquid which is a poor solvent of the alkaline substance by the aid of not exceeding 25 percent of an alcoholic solvent of said alkaline substance, said alcoholic solvent being miscible with the said poor solvent to provide a stable dispersion of the alkali substance, said alkaline substance being present in quantity for providing an alkaline concentration of 0.05 to 1 gram of alkali expressed as sodium hydroxide per 100 cc. of reagent.

'7. A process of reducing th tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially .of an alkaline substance having a stronger basic nature than ammonia, an alcohol effective as a solvent for the alkaline substance, and an organic diluent liquid which is a poor solvent for the alkaline substance but is miscible with the alcohol solution of the alkaline substance to give a dispersion.

9. A process of-reducing the tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of an alkaline substance having a stronger basic nature than ammonia, a monohydric alcohol con-- taining 3 to 8 carbon atoms and efiective as a solvent for the alkaline substance, and an organic diluent liquid which is a poor solvent for the alkali but is miscible with the solution of the alkaline substance in said monohydric alcohol to give a dispersion.

10. A process of reducing the tendency of wool to felt, which comprises treating the wool containing 12 to 18 percent of water for substantially one hour at a temperature of substantially 12 to 30 degrees C. with a reagent containing not more than substantially two percent of water and consisting essentially of caustic soda, n-butyl alcohol, and petroleum distillate having a boiling range of 150-260 degrees C., the caustic soda being present in the proportion of 0.2 to 0.7 gram per cc. of reagent, and the petroleum distillate forming at least '75 percent of the reagent.

11. A process as in claim 1 in which the treatment is applied to a material containing wool and other fibres.

12. Wool treated by the process of claim 1, and characterized in having the interior of the fibre substantially unchanged and possessing the tensile strength, softness of handle, durability and to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of a caustic alkali having a stronger basic nature than ammonia dispersed in a major proportion of a volatile hydrocarbon liquid which is a poor solvent for th alkaline substance by the aid of a minor proportion of an alcohol in which at least a part of said substance is dissolved, said hydrocarbon liquid being miscible with the solution of the alkaline substance in said organic solvent to give a dispersion.

14. .A process of reducing the tendency of wool to felt, which comprises treating the wool with a reagent containing not more than substantially two percent of water and consisting essentially of caustic soda dispersed in a major proportion of a volatile hydrocarbon liquid which is a poor solvent for the caustic soda by the aid of a minor proportion of an alcohol in which at least a part of said caustic soda is dissolved, said hydrocarbon liquid being miscible with the solution of caustic soda in said alcohol to give a dispersion.

ARCHIBALD JOHN HALL. FREDERICK CHARLES WOOD.