US2173243A

US2173243A - Process for treating fibrous materials

Info

Publication number: US2173243A
Application number: US183092A
Authority: US
Inventors: Howard A Young
Original assignee: United States Rubber Co
Current assignee: Uniroyal Inc
Priority date: 1938-01-03
Filing date: 1938-01-03
Publication date: 1939-09-19
Anticipated expiration: 1956-09-19

Description

INVENTOR 2 Sheets-Sheet l H. A. YOU NG PROCESS FOR TREATING FIBROUS IATERIALS Sept. 19; 1939.

. O ZQEAW LMQ FZuUtuL ZOELnOnEQ hZuQtmL y ya/mm 4. )w/ra BY ATTORNEYS Sept. 19, 1939. H. A. YOUNG 1 2,173,243

PROCESS FOR TREATING FIBROUS IATERIALS Filed Jan. 3, 1938 2 Sheets-Sheet 2 "l .LNELLNOI) 00v OIWHOA NOLLlSOd 3C1 .LNQ'JHHd ATTORNEYS Patented Sept. 19, 1939- UNITED STATES raocass ron Tammi} r'nmous MATERIALS,

Howard A. Young, Wcstfield, N. .L, assiznor, by mesne assignments, to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application January s, 1938, Serial No. 183,092

10 Claims. (01. 91-68) This invention relates to a process for treating fibrous material and more particularly to a. process for incorporating treating materials for waterrepelling, softening, strengthening, sizing, luster finishing or other finishing purposes in textile fabrics or other fibrous materials.

Various methods 'are known for incorporating treating substances in fibrous material from colloidal aqueous dispersions of such treating substances. Fibrous materials in the f orm of loose .fibers or in the form of textile fabrics or other association of fibers, have been introduced into a bath containing the desired amount of dispersed colloidal substance and the fibrous material cir- 5 culated.with. or through the bath or-the bath circulated through the fibrous material until some or all of the colloidal substance has been incorporated in the fibrous material. In these cases,

the dispersed material has been deposited on the rial with a, coagulant for the dispersed particles.

of the bath so that the fibrous material carries an excess of such coagulant, or by the previous preparation of a bath containing dispersed particles having an electrical charge opposite in sign to that carried by the fibrous material so that the dispersed particles become coagulated on the fibrous material byvirtue of the neutralization of the particle charges.

According to the present invention, treating material for water repelling, softening, strengthening, sizing, luster'finishing or other finishing purposes is deposited on fibrous material by a 40 non-coagulative deposition from an aqueous dispersion of the colloidal treating material which is in its isoelectric zone. Dispersions of colloidal substance generally owe their stability, that is,

their inability to settle out or coagulate, to the 45 presence of electrical charges carried by the parfl ticles of the dispersed phase. Charged colloidal particles will migrate in an electrical field or towards an oppositely charged body. There is, however, as is well known, a region of hydrogen ion activity where the positive and negative charges on the dispersed particles are. equal to each other and where the chargeson the dispersed particles are neutralized. This region of electrical neutrality of the dispersed particles is called the iso- 65 electric range or zone and the midpoint of this range is termed the isoelectric point. Dispersed particles having zero charge in their isoelectric zone will;generallycoagulate unless previously protected by an adequate amount of suitable sta- 60 bilizer. a

- material, and the fibrous'material is allowed to remain in contact with such an isoelectric dispersion, under normally non-coagulative conditions for the dispersion, that is, under conditions which would not produce coagulation of the dis-- persion itself were it not in contact with the fibrous material, untilthe desired amount of colloidal material has been deposited onto the fibers. Since the dispersion is stable and the conditions of treatment of the fibrous material with the dispersion would not coagulate the dispersion itself, and the dispersion is further isoelectric and hence contains no charged particles, that will migrate to an electrically charged body, the deposition of the colloidal particles on the fibrous material is a non-coagulative deposition. Such a non-coagulative deposition or union of the dispersed colloidal particles and the fibrous material is termed in this specification sorption and the' capacity of a given fibrous material to sorb a colloidal material from a given dispersion is the sorptive capacity of such fibrous material. The dispersion may remain in contact with the fibrous material at room or at elevated temperature providing, of course, that the dispersion contains sufiicient protective so that coagulation would not take place in the absence of the fibrous material under the time and temperature conditions of the 'rial. The greater the amount of protective over the minimum necessary to stabilize the dispersion of treating material in the isoelectric zone in the absence of the fibrous material, the slower will be the rate of deposition of the colloidal particles from the dispersion onto the fibrous mate'- rial. I have discovered, however, that in all cases I the rate of sorption oi the colloidal particles from the same-treating bath onto the fibrous material is greater in the isoelectric zone than at a pH on either side of the isoelectric zone, regardless of whether the particles are given a positive or negative charge by so shifting the pH of the treating bath out of the isoelectric zone, and regardless of the sign of the charge on thefibrous material. This may readily be seen from the'accompanying drawings in which:

Figure 1 is a chart showing the amount of lithopone deposited from a dispersion of lithopone deposited from a dispersion on woolen fabric in' on woolen fabric in different periods of time at various pHs according to the procedure of Example 1;

Figure 2 shows similar curves for the deposition of lithopone from a dispersion on silk fabric according to Example 2; and

Figure 3 illustrates the amount of zinc oxide bers, as of wool, 'silk, cotton, viscose or acetate rayon, linen, cellulose and the-like, or mixtures of the same, may be used, and these may be undyed, mordanted, dyed or otherwise treated so long as they are not in association with free coagulant which in the absence of the fiber would itself produce coagulation of the aqueous dispersion of colloidal material. Asbestos fibers can also be treated according to the present invention if the coagulants that are naturally associated with the fibers have been removed, or inactivated as by insolubilization.

Various materials which can be dispersed in an aqueous medium, with or without the addition of dispersing agents, may be used for the treatment of fibrous material according to the present in vention. Such treating materials which can be colloidally dispersed in an aqueous media include, proteins, such as casein, gelatin, glue, albumen, serecin, and lecithin; carbohydrate gums, such as gum tra'gacanth, gum acacia, locust beangum, karaya gum, and gum arabic; waxes, such as montan, carnauba and beeswax; oils such as castor oil, olive oil, mineral oil and neats-foot oil; dialkyl phthalates; fatty acids, such as stearic, oleic and palmitic acids; soaps; petrolatum;.paraflin; asphalt; certain hydrogenated bituminous substances; certain halogenated aromatic compounds; certain halogen derivatives of hydrocarbons; water insoluble salts; natural resins, such as rosin, gum dammar and gum copal, and artificial resins such as phenol-formaldehyde resins, acrylic acid resins, glyptal resins, vinyl resins, and urea-formaldehyde resins. As specifically claimed in a copending application filed concurrently with this application, aqueous dispersions of rubber and rubber-like materials may also be used to treat fibrous materials according to the present invention.

The treating materials can be dispersed in water generally with the aid of dispersing agents by methods well known in the art, and the preparation of these dispersions, generally in concentrated form to be diluted in preparing the treating baths, but, if desired, originally in a concentration suitable for a treating bath, forms no part of the present invention. Those of the above listed treating materials which are also protectives may act as their own protectives when bringing the pH of the treating baths into the isoelectric zone, or they may be used to protect treating baths prepared from others of the above listed treating materials. A list of materials commonly used as dispersing agents is set forth below. Liquid water-insoluble treating materials may be dispersed or emulsified in water with the aid of a dispersing agent by mixing in a highspeed stirrer or homogenizing in a so-called colloid mill as well known in the art. Finely divided solid treating materials may readily be ball milled with water in the presence of a dispersing agent until the particles will remain in colloidal suspension. Treating materials that are plastic or which can be made plastic as by breaking down" on 'a mill or kneading" in a mixing device, such as a Werner and Pfleiderer mixer, may have the dispersing agent mixed into the plasticized mateloidal treating material in its isoelectric zone for use according to the present invention, careshould be taken to have sufii'cient protective present so that the isoelectric dispersion would not ,itself coagulate under the time and temperature conditions of the treatment with the fibrous material, if the dispersion were not in contact with the fibrous material. At the-same time, too much protective should not be used or the rate of deposition of the treating material will be too slow due to the excess of protective, and the sorptive capacity of the fiber for the over-protected colloidal material will be reduced, the bath will not exhaust, and deposition of the desired amount of colloidal material onto the fibers will not satisfactorily take place. With a given treating material and a given fibrous material,- it is a very simple matter empirically to adjust the amount of the desired protective so that in the isoelectric zone the otherwise stable bath will readily deposit the required amount of treating material on the fibrous material in a desired time.

A simple method may be used for determining the isoelectric range of the aqueous disper sion of colloidal material with a given protective, namely, by determining the migration or mobility of the dispersed phase of the dispersion at different pH's under the influence of an electric potential and noting the pH range of zero mobility or electrical neutrality. Other well known methods of determining the isoelectric point or zone are based on the fact that at the isoelectric point, the osmotic pressure, viscosity, and conductivity are at a minimum. In adjusting the pH of the aqueous dispersion of colloidal material in order to bring it into its isoelectric zone, the pH may be lowered where necessary by means of acids, such as formic, acetic, tartaric, phosphoric, hydrochloric and sulphuric acids, as well as various acid salts, or mixtures of the same, and the pH may be raised, where necessary, by the addition of ammonia or other alkaline substance.

Two general classes of protectives may be used in preparing the aqueous dispersion of colloidal material, those of a colloidal nature and those vegetable mucilages, and starches are examples of colloidal protectives that may be used. Various known non-colloidal protectives may be used, such as certain 'salts of carboxyl (HOOM),

sulphonic (Br-$03M), sulfinic (Mom); 01 75' (RO.SO3M)' radicals, where the R may have a straight chain or ring structure and may contain substituent halogen, amino, nitro or hydroxyl groups. Other organic chemicals are well known protectives as certain benzene sulphonic acids,

their homologues and substitution products, naphthoic acids, aliphatic-aromatic acids, derivatives of hydro-aromatic series of acids, phenyl-glycine and derivatives.

In the case of the colloidal type of protective for the dispersed particles, the protective becomes attached to the colloidal particles of treating material and the thus protected particles of treated material assume the charge and to some extent the properties and behavior of the colloidal protective agent and hence the isoelectric of the protective. It is believed that when a non-colloidal protective agent which is capable of ionizing is used to protect a dispersion of colloidal treating material, one of the ionized parts of the protective may fasten itself onto the colloidal material, and in so doing may shift the isoelectric range of the dispersed material somewhat in proportion to the amount of protective used. When a colloidal protective agent is used and the dispersion assumes the isoelectric-of the colloidal protective, the deposition of the dispersed particles of treating material will be accompanied by a deposition of the colloidal protective and especially when an excess of coloidal protective over that merely necessary to stabilize the bath in the isoelectric zone is used. This may or may not be desirable. If it is objectionable for the colloidal protective to be deposited with the treating material, then a non-colloidal protective agent where possible should be used.

Frequently both the colloidal and non-colloidal prot'ectives may become modified by association with other ingredients of the treating bath, such as the colloidal treating material itself or alkaline or acidic materials or salts which may be added for this purpose or because it is desired to include them in the composition, with the result that the complex associated colloids in the dispersion exhibit an isoelectric point different from that of the protectives. However, it is always a simple matter to locate the isoelectric range in terms of hydrogen ion activity by means of cataphoretic tests, 1. e., the conventional observations on colloid movement or migration under an impressed electrical force.

Various examples of the treatment of different fibrous materials with aqueous dispersions of various treating materials according to the present invention are set forth below, but these are merely exemplary of the invention and are not intended to be limitations thereon. The pH of the dispersions in these examples was lowered by means of formic acid because it is a volatile acid and has little effect upon the color and characteristics of fibrous materials, but other electrolytes as above described may be used satisfactorily for this purpose.

Example 1 In this case-lithopone was deposited on a woolen fabric. A lithopone paste-of the following composition was first prepared, the casein being soluthe water and the whole ball milled for over twelve hours.

Parts by weight Lithopone a 30 Casein Water 76 Various treating baths of the following composition containing amounts of formic acid ranging from 0 to were made from the above lithopone paste: I 1 l0 Parts by weight Solids of the lithopone paste v .5 Aquarex D .1 Formic acid 0 to 10 Water To make 100 The dispersed lithopone particles were protected by the solubilized casein 'and the casein in turn protected against coagulation on the addition of the formic acid by the fAquarex D. Aquarex cessfully be used in preparing dispersions of colloidal material for treatment of fibrous materials according to the present invention may be men'- I tioned Mertanol which is a naphthalene sulphonic acid derivative, Gardinol. WA" which is the sodium salt of sulphated lauryl alcohol, 3

Gardinol- LS which is the sodium salt of sulphated oleyl alcohol, Igepon T which is a fatty ester of a sulphonated aliphatic compound,Arc-

tic Syntex AX" which is an oleic acid ester of sulphated aliphatic compounds of the formula R-COOXSOzNa, Arctic Syntex T which is an oleic acid ester of sulphated aliphatic compounds of the formula R-CONHXSOaNa, Emulphor O which is a condensation product of ethylene oxide and higher alcohols, Sulphanol" which is 40 a sulphated fatty alcohol, and "Laurel Supersulphate" .which is a hydrogenated oil which is sulphonated. I

Pieces of woolen fabric were immersed in about 20 times their weight of various treating baths 415 at 90 F. containing formic acid in amounts from 0 to 10% of the bath, and" agitated in the baths for different lengths of time, namely, 5, 10 and 15 minutes, before removing from the baths, rinsing and drying. The percent deposition of lithopone on the fabrics under various pH conditions of the treating baths in the 5, 10 and 15 minute periods were determined, and these results are shown in the chart of Fig. 1. Throughout the specification, the percent depositionvof the various treat- 65 ing materials on the fibrous material is calculated as percent gain based on the untreatedfibrous material. The isoelectric zone of the treating bath extendedv from pH 1.7 to 2.1 and its midpoint at pH 1.9 was the isoelectric point as determined by .cataphoretic tests. The amount of lithopone deposited on the woolen fabrics in the 5, 10 and 15. minute periods of treatment in Y the various treating baths which were in the pH .range of 7 to.1.1, corresponding to formic acid contents of the bath ranging from 0 to 10%, are shown on the curves marked A, B andC respectively. The curve D shows the decrease in pH" of the treating bath with increase of the formic acid content of the bath, and is typical of curves where acid content is plotted against pH.' The amount of formic acid added to the bath-is considered the formic acid content of the bath. From each of the curves A, B and C, it will be seen that the deposition of lithopone is con 15 obtained in the isoelectric zone.

either side of it. The amount of lithopone deposited at the isoelectric point in 5 minutes was about 6.7%, in 10 minutes about 8.1% and in 15 minutes about 9.7%, which latter figure represents deposition of substantially all the lithopone in the bath. In this latter case there was substantially complete exhaustion of the bath.

Raising the pH from the isoelectric zone results in. the assumption of negative charges by the dispersed lithopone particles and greatly reduces the amount of deposit of lithopone on the fabric in a given time. At pHs higher than 4 substantially no lithopone will deposit on the fabric from a dispersion by simple treatment of the fabric with the dispersion. Shifting the pH below the isoelectric range results in the assumption of positive charges by the dispersed particles and at first likewise reduces the amount of lithopone deposited on the fabric in a-given time. This reduction in the amount of dispersed particles sorbed on the fabric in a given time continues with a decrease in pH from the isoelectric point 1.9 to a pH of about 1.65, corresponding to an acid contentof the bath of about 2%. On

further reduction of the pH below 1.65, as to 1.1 by increasing the acid concentration from 2% to 10%, the amount of lithopone deposited in a given time increases somewhat above the amount deposited at a pH of 1.65, although it does not in this case approach the amount of deposition When the acid content of the bath isincreased over 2%, that is, when the pH is lowered below 1.65, the bath becomes destabilized and flocks and coagula appear in the bath. When the fabric is immersed in such a bath below a pH of 1.65 visibly coarse particles of lithopone are deposited on the wool. It is also obvious from the change in the shape of the curve that a different mechanism is operating to deposit the lithopone at pHs below 1.65 than at pHs above 1.65. The undesirable deposition of visibly coarse particles of lithopone on the wool at pHs below 1.65 is believed to be the result of the chemical reaction of the excessive amounts of acid in these low pH ranges with the protectives on the lithopone particles, with the result that the protectives lose much of their protective power, and the: consequent loss of stability permits the formation by coagulation of coarse particles of lithopone which then attach themselves to the fibers when the fabric is immersed in such a treating bath.

Example 2 Example 1, namely, 5, 10 and 15 minutes, before removal from the bath, rinsing and drying. The percent lithopone deposited on the fabrics under various pH conditions of the treating baths in the 5, 10 and 15 minute periods were determined, and these results are shown in the chart of Fig. 2. As may be seen from Fig. 2, the isoelectric zone of the treating bath was, as to be expected, the same as in Example 1 and extended from a pH of 1.7 to 2.1 with the isoelectric point at a pH of 1.9. The amount of lithopone deposited on the silk fabrics in the 5, 10 and 15 minute periods of treatment in the various treating baths in the pH range of 7 to 1.1, which corresponds to the range of formic acid content of the baths of to 10% are shown on the curves marked E, F and G respectively. The curve marked H shows the change in pH of the treating bath with the formic acid content of the bath and is the same as the corresponding curve D of Fig. 1. A comparison of the charts of Figs. 1 and 2 shows that the woolen fabrics of Example 1 had a greater capacity for the dispersed lithopone particles than the silk fabrics of Example 2. The amount of lithopone deposited on the silk at the isoelectric point in 5 minutes is about 6.5%,in minutes about 7%, and in minutes about 7.4%. Due to the lower rate of deposition of the lithopone particles on silk fabric than on woolen fabric, the rate of change in deposition with changes in pH is less with deposition on silk than on wool, and hence curves E, F and G display wider optima than than curves A, B and C.

- The maximum deposition, however, in every case is in the isoelectric zone.

fabrics 'as the pH is shifted in either direction.

from the isoelectric zone but not as rapidly as in the case of the woolen fabrics of Example 1.

Raising the pH out of the isoelectric zone results in the assumption of negative charges by the dispersed lithopone particles and reduces the amount of deposited lithopone on the fabric in a given time. Shifting the pH below the isoelectric range results in the assumption of positive charges by the dispersed particles and at first likewise reduces the amount of lithopone deposited on the fabric at a given time. The reduction in the amount of dispersed particles sorbed on the fabric in a given time continues with a decrease in pH to-a pH of about 1.35, corresponding to an acid content of the bath of about 5%. On further reduction of the pH from 1.35 to 1.1, by increasingthe acid concentration lithopone on woolen fabrics as shown in Example 1, except that in case of woolen fabrics, the

change in the shape of the deposition curve takesplace at a pH of 1.65 rather than at a pH of 1.35

as in the case of silk fabrics.

Example 3 In this case zinc oxide was deposited on a woolen fabric from a dispersion of zinc oxide protected by a colloidal protective, namely, sodium caseinate and sodium oleate. A protected colloidal zinc oxide paste of the following composition was first prepared by ball milling for over twelve hours:

' Parts by weight Zinc oxide 1,000 Sodium oleate 150 Casein 25 Sodium hydroxide 1.25 Water -l 1,760

Various treating baths of the following composition containing amounts of formic acid ranging from 0 to 2% were made from the above zinc oxide pastez- 45 change which takes place in the deposition of the A Samples of woolen fabricwere immersed in about twenty times their weight of the various treating baths at 90 F. containing formic acid in amounts from to 2% of the bath, and agitated in the baths for 15 minutes'before removal from the baths, rinsing and drying. The percent zinc oxide deposited, on the fabrics under the various pH conditions of the treating baths were determined, and these results are shown in the chart of Fig. 3. The isoelectric zone of the treating bath extended from 6.20 to 6.35 and the bath is shifted away from the very sharply defined isoelectric zone. The curve J clearly demonstrates again that sorptive deposition is a maximum in the isoelectric zone and falls of! as the pH is shifted away from, the isoelectric zone in either direction. As may be seen from curve J, the deposition of zinc oxide in 15 minutes at 90 F. at a pH of 11.2 where no acid had ben added was only .4%. In order to bring the treating bath into the isoelectric zone, it was necessary to add only .05% formic acid, whereupon in 15 minutes at 90 F., 12.3% of zinc oxide, which was substantiallyall the zinc oxide in the bath, deposited on the fabric. The "Aquarex D in the treating bath formulae was used to prevent coagulation of the sodium caseinate and sodium oleate protective on acidification of the various treating baths made from the zinc oxide paste on addition of the formic acid.

Curvessimilar to those of Figs. 1 to 3 may be obtained for the deposition of various other colloidal treating materials on various types of fibrous materials and such curves will all show that the sorptive deposition of colloidal material is a maximum when the treating bath is in the isoelectric zone. In the remaining examples, however, it will be sufficient to illustrate the deposition of various colloidal treating materials upon various fibrous materials at a single pH in the isoelectric zone 'of the treating bath, and in some cases to compare such isoelectric deposition with a deposition under similar conditions at a pH outside the isoelectric range.

Example 4 Partsby weight Solids of lithopone paste 10. Aquarex D" a 1 Formic acid 1 Water 88.6

The above treating bath was padded onto a silk fabric by passing the fabric through the above treating bath and. squeezing through so that the fabric contained about 100% of its weight of the treating bath, that is, a weight of liquid bath in the fabric about equal to the weight of the fabric, or a so-called bath-to-goods" ratio of 1:1. The pH of the treating composition which was in the isoelectric zone was 1.90,

a as in Examples 1 and 2. The fabric with the thus absorbed bath was allowed to rest at room temperature for 20 minutes, in which time substantially all the dispersed material deposited on the fabric, as shown by a clear rinse. After rinsing and'drying, the fabric showed a gain in weight 'of 11.6%.

- Ea'ample 5 In this case woolen fabric was treated with a dispersion of casein.- The casein was first solubilized by means of a small amount of sodium fluoride and borax in water in a' manner well known in the-art, and the thus solubilized casein was made into a colloidal treating bath having the following composition:

' Parts by weight- Casein .5 Aquarex D" .2 Formic acid 8.8 Water 95.5

The pH of this bath which was in the isoelectric zone was 2.1. The woolen fabric was immersed in about 20 times its weight of this bath and agitated for minutes at 90 F. and then rinsed and dried. It showed a gain in weight of 1.8% casein. The treating bath without the formic acid, and hence not in its isoelectric zone, with a similar 10 minute immersion at 90 F., and rinsing and drying, showed only a 1.6% pick-up of casein. The "Aquarex D" was used to protect the casein against coagulation in the isoelectric zone.

Example 6 A commercial wax known as Sunproof wax was deposited from an emulsion onto wool fabric. The Sunproof wax dispersion was made by emulsifying 88 parts of Sunproof wax in 300 parts of water by means of 9 parts of oleic acid and 3 parts of triethanolamine as follows: The Sunproof wax 'was melted and the oleic acid added to it and the whole heated to 75' C. This was added to the triethanolamine dissolved in 100.parts of water at 75 C. in a .thin stream under a high speed stirrer and the stirring continued for 10 minutes after the wax and oleic acid had been added. The stirring was continued while 200 parts of cold water was added in a thin stream, and this was stirred for 30 minutes after all the water had been added.

The treating bath was prepared from the above emulsion by diluting and acidifying in the presenceof a stabilizer and had the following composition:

' Parts by weight Solids oi the above dispersion .5 Aquarex D"- .i Formic acid 5. Water- 84.4

The pH of the bath which was in the isoelectric zone was 1.66. The woolen fabric was immersed in about-20 times itsweight of the treating bath and agitated for 10 minutes at 90 .F., and the fabric was then removed leavinga slightly hazy bath. After rinsing and drying the fabric showed a gain in weight of 10.5%. The gain-in weight of fabric treated in, the same manner but without the addition of the formic acid to bring the treating bath in its isoelectriczone was only 5.6% under the same treating conditions.

Emmple 7 Woolen fabric was treated with an emulsion of NujoP' which is a white mineral oil. 93 parts of Nujol were emulsified in 100 parts of water by means of parts of oleic acid and 2 parts of triethanolamine, and a treating bath of the following composition was made up from this emulsion.

, I Parts by weight Solids of "NuJoP emulsion .5 "Aquarex D .06

Formic acid 5. Water 84.45

treated according to the present invention with a composition:

Parts by weight Potassium oleate .5 "Aquarex D" .1 Formic acid 4 15. Water 84.4

- was 1.14.

commercial dispersion of Bakelite known as Bakelite Emulsion XW-9060, the compomtion of which was not known. A treating bath was made from the Bakelite Emulsion xw-soe'o" having the following formula:

. Parts by weight Solids of Bakelite Emulsion xw-9oco" .5 "Aquarex D .1 Formic acid 18. Water 81.4.

The pH of this treating bath which was isoelectric trample I 'wooreu fabric was immersed in about 20 times its weight of this treating bath and agitated for 10 minutes at 80 F., and after rinsing and drying showed a gain of 7.8%. A similar treatment of the woolen fabric but without the addition of the formic acid to bring it into the isoelectric zone, showed a gain of only 4.1%.

Example 9 Viscose rayon fabric was immersed about 20 times its weight'of the treating bath made from the "Bakelite Emulsion XW 9060, as shown above, and agitated forminutes at 80 F., and

the bath completely exhausted. The gain in weight of the fabric after rinsing and drying was Example 10 So-called Immunized cotton fabric was immersed in about times its weight of the treating hath made from the Bakelite Emulsion W- 9060" above and agitated for 15 minutes at 80 F.

'I'he bath again exhausted. After rinsing and drying, the fabric showed a gain of 10%.

In the next three examples various fabricswere treated according to the present invention with dispersions of soap. In each of the following examples the treating, bath had the following The pH of this bath which was in the Mim none was 1.88.

ofonly 38%.

' Eumrile 11 Woolen fabric immersed in about 20 times its weight of the above treating'bath showed a gain of 9.4% after agitating for 10-minutes at 85 1"., 5 rinsing and drying.- Without acidification and consequent reduction of the pH to the isoelectric, in 10 minutes immersion at 85 F., rinsing and drying as above, the same fabric showed a gain silk fabric in about 20 times its weight of the above potassium oleate treating bath and agitated for -10minutes at 80 F., rinsed and dried, showed a 13.1% gain. The treating bath in this case was exhausted.

. Emmple 13 Tanned viscose rayon fabric immersed in about 20 times its weight of the above dispersion and agitated for 10 minutes at 80" F'., rinsed and dried, showed a gain of 9.1%. The bath in this case also exhausted.

The above examples clearly illustrate the present invention as applied to various treating materials for fabrics. l 'urther examples showin the treatment of fibrous materials with isoelectric rubber dispersions will be found in the application filed concurrently with this application referred to above. It will be obvious to those skilled in the art that various other treating baths than those illustrated in the above examples may be developed for the treatment of various fibrous materials using the principles of the present invention.- In view of the many changes and modifications that may be made without departing from the principles underlying the invention, reference should be made to the appended claims for an understanding of the scope m of the invention. I 'ihis application is a continuation-impart of application Serial No. 149,269, filed June 19, 1937. Having thus described my invention, what I claim and desire to protect by Letters Patent is: 45 1. The process of treating fibrous material which comprises associating a bath of an aqueous dispersion of colloidal treating material which is at a pH in approximately its isoelectric zone with fibrous material under normally noncoagulative conditions for the dispersion, said dispersion being stable ,in the absence of fibrous material but capable of depositing substantially all .of its dispersed particles of treating material on fibrous material under normally non-coagulative as conditions for the dispersion, and maintaining the fibrous material associated with said bath under normally non-coagulative conditions for the dispersion until the desired amount of treating material has been sorbed on the fibrous ma- 5( terial.

2. The process of treating fibrous material which comprises associating a bath of'an aqueous dispersion of colloidal treating material which is at a pH in approximately its isoelectric 51 zone with fibrous material under normally noncoagulative conditions for the dispersion, said dispersion containing sumcient protective to stabilise it in the isoelectric zone in the absence of fibrous material but insufiicient protective to pre- 71 vent substantially all the dispersed particles of the dispersion from being capable of depositing on fibrous material undernormally non-coagulative conditions for the dispersion, and maintaining the fibrous material asociated with said bath 11 under normally non-cosgulatlve condltlonstor lative conditions for the dispersion, said disperthe dispersion until the desired omount of treatinci muterlul has beencorbed oh the fibrousmater el. l

3. The process or treutlngfibrous material which comprises associating a both of an aqueous dispersion oi colloidal trectlugmaterlal which is at a, pH in approximately its lsoeleotric zone with fibrous material under normally non-coaguletlve cohdltlohs for the dispersion, said crispersioh containing an acid and suillclelzrtv protective to stabilize it in. the lsoelectrlc some in the ob,-

- some or" fibrous materiel but iusufilclent protective to prevent substantially all the dispersed particles or the dispersion from being capable of rlepositing on fibrous materiel under normally nonooegulotive conditions for the dispersion, and. maintaining the fibrous materiel associated with said both under normally nou-coegulutlve cohdltious ror the dispersion until the desired amount or treating materiel has been deposited on the fibrous materiel.

The process of treating fibrous material which comprises associating e, bathof an aqueous dispersion of colloidal treating material which is cut a. pH in approximately its isoelectrlc zone with fibrous material under normally non-coaguslon containing an acid cud sumcient protective to stabilize it at elevated temperature in the iso-- electric zone in the absence or fibrous material but insumcientprotective to vprevent substem tially all the dispersed particles or the dispersion from being capable of depositing on fibrous me.- terlul at elevated temperature under normally non-coagulotive conditions for the dispersion, and-- maintaining said fibrous metericlcssociated with said both at elevated temperature under normally noh-coagulative conditions for the dispersion until the desired amount of treating materiel in the dispersion has been deposited on the fibrous material.

5. The process oftreating fibrous material which comprises associating with fibrous material a bath of an aqueous dispersion of colloidal treating material which is at a, pH in approximately its isoelectric zone, said both containing suthcient protective so that it is' stable in its isoelectric zone in the absence of the fibrous ma,- terial but containing lnsuflicient protective to prevent substantially all the dispersed particles in the bath from being capable of depositing on the fibrous material under normally non-coe.g'

ulative conditions for said dispersion, and maintaining said fibrous material associated with said bath under normally non-coagulative conditions for said dispersion until at least part of the treating material has been sorbed on the fibrous material.

6. The process of treating fibrous material which comprises assoclating wlth fibrous mate-' rial a bath of an aqueous dispersion of colloidal treating material which is at a; pH in approximately its isoelectric zone, said bath containing sufllcient protective so that it is stable in its isoelectric zonein the absence of the fibrous mate rial but containing insumcient protective to prevent substantially all the dispersed particles in the bath from being capable of depositing on the fibrous material under normally non coagulatlve conditions for said dispersion, and maintaining said fibrous material associated with said bath under normally non-coagulative conditions for r sold dispersion until substantially all the treat- 7 ing materiel-1n the dispersion hasbeen sorbed on the fibrous material. g V

7. The process or treating fibrous gmoterlal which-comprises associating with fibrous material at room temperature a bath of an aqueous dlsperslou of colloidal treating material which is at a. pH in approximately its lsoelectrlc zone,

it is stable in its lsoelcctrlc zone in the absence of the fibrous material but containing incumoleut protective to prevent substuutiully all the zlisperced pertlcles m the both from being copeble of depositing on the fibrous meterlol in the absence or tree coagulant on the fibrous materiel,-

ondmolutolhlng the bath associated with the fibrous material at room temperature and in the said both containing suficleht protective so that absence or tree coagulant ou the fibrous muterial until at least part of the treating material has been sorbed on the fibrous materiel.

b. The process of treating fibrous material which comprises associating with fibrous matcriel at room temperature a bath of an aqueous dispersion of colloidal treating material which is at a pH ln approximately its lsoelectrlc zone, said both containing sumcient protective so that it is stable in its lsoelectric zone in the absence of the fibrous material but cohtolnmg lhsufficleut protective to prevent substantially oil the dispersed particles inthe both from being capsble or depositing on the fibrous material, in the absence of free coagulant oh the fibrous material, and maintaining the bath ussoc'le tcd with the fibrous material at room temperature and in the absence of free coagulant on the fibrous moterlal until substantially all the treating material in the dispersion has been sorbed on the fibrous material.

.9. The process of treating fibrous material which comprises associating with fibrous mate rial ateleveted temperature a, both of an aqueousdispersion of colloidal treating material which is at a. pH in approxlmately its isoelectric zone, said bath containing sufllcient protective so that it is stable in its isoelectrlc zone in the absence of the fibrous material at elevated temperature but containing insufiicient protective to prevent substantially all the dispersed particles in the bath from being capable of depositing on the fibrous material in the absence of tree coagulant on the fibrous material, and maintaining the bath associated with the fibrous material at elevated temperature and in the absence of free coagulant on the fibrous material until at least part of the treating material has been sorbed on on the fibrous material, and maintaining the bath associated with the fibrous material at elevated temperature and in the absence of free coagulant on the fibrous material until substantially all the treating material in the dispersion has been sorbed on the fibrous materiel.

HOWARD A. YOUNG