US1947107A - Method of producing absorbent or resilient felt - Google Patents

Description

Feb. 13, 1934; PLUMSTEAD 1,947,107

METHOD OF PRODUCING ABSORBENT OR RESILIENT FELT Filed Sept. 4, i931 Jbazeph E: Humiead,

as I 7 Mi, xwam, 2 4// Patented Feb. 13, 1934 UNITED STATES- METHOD or PRODUCING ABSORBENTQ on nnsmmn'r FELT Joseph E. Plumstead, Wilmington, Del., assignor to The Jessup & Moore Paper 00., Philadelphia, Pa., a corporation of Application September 4, 1931. SerialNo. 561,242

41 Claims. (01'. 92-13) My present invention relates to an improved method of producing kinked, curled, or crimped fibres from finished or prepared cellulosic fibrous pulp material and to theproduction of a sheet 6 of material having substantial. bulk and absorbency and resiliency, andto the production of a J felted product having substantial resilience and waterproof qualities.

An object of the invention is the production 10 of the curled or crimped fibres from finished or prepared pulp without the necessity of using as drastic treating solutions as have heretofore been used to produce the desired degree of bulkiness in the felted fibrous sheet.

or expressed in another way, this object is to provide a method capable of producing a sheet having an increased degree of bulkinws or absorbency, using the usual or ordinary treating solutionv or treating solutions of less or equivalent drasticity. In other words, for a treating solution of given drasticity, the method of the present invention produces increased bulk and absorbency in the resultant sheet over that produced by methods used heretofore.

crimped fibres by treatment with less'drastic treating solutions and in a limited and controlled time. v I The invention aims to substitute for the purely chemical curling treatment, acombination of controlled or limited mechanical treatment with' a less drastic chemical treatment.

Another object of the invention is rendering the fibres more susceptible to -curling by mechan- 35109.1 gelatinization of the fibres. or in other words,

producing a reactive gel on the surface of the fibres by means of a mechanical gelatinizing agent prior to or as a concomitant of the treatment with thecurling agent, which gel is of 40 increased reactivity or susceptibility to the action of the curling agent.

The invention also aims to increase the susceptibility of the fibres to the curling agent by mechanical treatment producing partial bruising of the individual fibres.

Another object .is to produce curled and crimpedor kinked fibres which result ma puffed, swollen and springy or spongy eflect 'in the resulting felted material into which the curled fibre is formed, producing bulk and'absorbency therein with minimum weight without .need of emphasis on the securing of maximum reaction of chemical upon the entire surface of the fibre. Another object is to provide treating solutions by utilization of certain chemicals for the pro- The invention aims to produce curled orduction of curling, kinking 'or crimping of prepared fibres.

Another object is to produce the less drastic treating solutions by utilization of spent or partially spent saponaceous liquors either fortified or unfortified by fresh reactive chemicals, or by preparing fresh solutions of weaker or less drastic chemicals.

Another object is to produce the less drastic treating solutions by using less drastic chemicals as or by using a less concentrated solution of the same or an equally drastic chemical as that used in the usual treating solution, or by using combinations of two or more chemicals.

Another object is the production of a felted product of substantial absorbency and resiliency.

A-further object is to provide a product which has a marked afiinity for waterproofing agents.

Another object is the production of a resilient waterproof relatively non-absorbentfelted. prod- 16 not.

Other objects will be apparent from the accompanying disclosure. v

The drawing shows diagrammatically and for purposes of illustration, without regard to actual dimensions, a fibre in 1 between balls of a ball mill, and in Fig.2 approximately the kinked, curled or crimped condition of the fibre after bruising at one or more points and treated with the treating solution. No attempt at actual relas5 tive size between the balls and the fibre has been madein the drawing.

Fig. 3 represents diagrammatically a ball mill or equivalent fibre bruising apparatus, in which 3A indicates horizontal ribs or bars for elevating 90 the balls 3E and dropping them in the rotation of the cylinder 3 by suitable drive means as 3F.

Inlet and outlet are indicated at 3C and 3D.

The invention involves treating finished or prepared cellulosic fibres with treating solutions less drastic or powerful than the usual caustic lye treating solution, whether less drastic because of increased percentage of diluting solvent or because of the use of a less active or more inert chemical, and supplementing the treatment to accelerate the curling or crimping action of the fibres by subjecting the fibres tc'ta bruising action for a length of time and in an apparatus such as will only partially'bruise the length of the individual fibres. The partial bruising at one or more points along the individual fibre length is ac complished according to the present invention by v regulating and controlling the time of subjection of the fibres to the bruising action. This provides vulnerable points by the bruised portions, causing selective, localized, or focal reactivity of the physico-chemically reactive treating solution, whereby the individual fibre throughout its length is dififerentially affected and will bend,

and localized gelatinization for the production of pufied pulp but also, if continued, will produce a general gelatinization which will make the whole fibre more reactive and will also, in a measure commensurate with the degree to which it is carried, replace the ordinary paper mill hydration and gelatinization equipment, namely, heaters, Jordans or other type of hydrating equipment.

The invention therefore also involves the subjection of the fibres to mechanical treatment producing such gelatinization of the surface of the fibres as to form a reactive gel thereon particularly responsive to the curling agent to accelerate the curling of the fibres.

The treatment of the finished cellulosic fibres with the less drastic treating solution is carried out preferably at the same time with the mechanical action to which the fibres are subjected, although it is desired to not limit the invention to this as the treating and mechanical action may be carried out successively, if desired.

Any suitable means may be employed for carrying out the bruising action, preferably a means capable of thoroughly mixing the treating solution with the fibres during the bruising treatment and capable of applying a localized bruise or abrasion of the fibre.

I have found thatthe bruising action is eflectively accomplished by means of balls in a rotary mill provided with means for carrying the balls upwardly and dumping them upon the mass of fibre and treating solution and other balls in the bottom of the mill.

The ball mill or other bruising apparatus thus requires a certain irregularity of interior construction providing for carrying the bruising media upwardly and then dumping it against the mass, in order to produce best results in effecting the bruising action, selective treatment, and accelerated curling, according to my present invention.

Partial bruising, mimng, and treating with less powerful or less drastic or other treating solution is preferably all carried out in the ball mill to produce the mnking of the fibres.

The treating solution which may be less drastic than the usual caustic lye treating solution may include any of the following chemicals: sodium hydroxide, sodium sulfide, sodium sulfate, sodium sulfite, sodium carbonate, sodium chloride, sodium phosphate, sodium nitrate, aluminum salts, ammonium hydrate, calcium chloride, calcium hydrate, and soaps, such as spent or par-,

tially spent saponaceous liquors, which saponaceous liquors are either fortified or unfortified by fresh reactive chemicals such as caustic lye and sodium sulfide.

Zinc chloride or other zinc salts. Cupro-ammonium compounds (e. g. a mixture usual caustic lye treating solutions (of about memo? of ammonium hydroxide and a copper salt) or other copper salts or copper compounds.

A solution of caustic lye (of about 2% to 18% concentration) which is less powerful than the 7%-24% concentration) may be used and will produce the desired effect upon the partially bruised fibre, the bruised'portions of the cellulose fibre being more reactive than the other portions. This solution will also be effective where the mechanical treatment is such as to provide a reactive gel surface on the entire body of the fibre.

The present invention therefore enables the use of weaker caustic lye solutions or other treating solutions of reduced power to accomplish the same bulk and absorbency of the felted sheet as is produced by purely physico-chemically kinked, curled, and crimped fibre. This is due to the increased sensitivity to treating solution of the portions of the fibre affected by the mechanical bruising action, to cause an increased or extra kinking, curling, or crimping of the fibre. This produced bulk and pufiiness of the felted sheet.

The less drastic treating solution of reduced power, may, of course, still be efiective enough to 100 tend to cause some slight kinking, curling, and

crimping along the whole length of the fibre.

The present invention aims to accelerate the kinking, crimping and curling effect by the partial bruising causing localized or focal reaction of a treating solution.

If the ball mill treatment were prolonged the progress of the physical condition would be marked as follows:-

Step (1). Focal bruising and focal gelatinization.

Step (2). Surface gelatinization extending along the entire fibre surface.

Step (3). An extension of gelatinization into the interior of the fibres.

Step (4). A mass gelatinization in which the fibres begin to lose their identity and form into a syrupy gelatinous homogeneous mass.

Of course for a continuous process no definite line can be drawn as to where one step leaves off and the other begins. It may be definitely stated however that the accelerated curling due to mechanical gelatinization stops with step two and beyond that point the curling action of the treating agent begins to be nullified by additional mechanical treatment. The present invention involves steps (1) and (2).

Therefore the regulation and control of the time element in the bruising apparatus or ball mill treatment is highly important in the production of a kinked, curled, and crimped fibre product resulting in a felting machine product of substantial bulk and absorbency.

Expressed in another way, the invention in one aspect involves a substitution of a mechanical means and less drastic treating solution for obtaining a given bulk and absorbency in the felting machine product by focal acceleration of the curling, crimping and kinking effect, in place of the more powerful physico-chemical treatment. 14 The more powerful physico-chemical treatment results in a product in which the individual fibres are affected throughout the length and body thereof to curl, crimp, and kink the same, with out the assistance of the bruising treatment.

A less drastic treating solution for producing a given type of product is used in the ball mill partial bruising treatment according to the present invention.

I am taking a finished pulp which may have 150 been originally produced from wood or, other vegetable sources according many of the known methods, and I am further treating it in .a new way toproduce a new product,a felting machine product having bulk and absorbency but comprising constituent individual fibres crimped or It is rather difilcult to place fixed limits on a product, the inherent characteristics of which are controlled by the physico-chemical degrees of treatment. In this particular case the physicochemical variables may be as follows:-- I

(1.) The chemical constituents of the treating solution.

. (2.) The relative percentages of these chemical constituents to each other. (3.) Percentage of total solids in the treating solution. a

(4.) The duration of the physico-chemical treatment.

(5.) The intensity of the bruising as controlled bythe size of the balls, distance of fall of same and consistency or density of mix.

(6.) Temperature at which treatment is carried out.

The product which I have produced might be described as a fibrous mass which due to its extreme freeness is incapable of being tested satisfactorily bythe standard Schopper Riegler freeness tester and requires a modified Schopper tester as described in volume XCI-No. 9 of the Paper Trade Journal, August 28th, 1930, written by Robert M. Boehm, using a bottom orifice of 9/ 64? opening. with the extremes of my method of treatment, using five liters of mixture and 25 grams of bone dry pulp, the bottom readings will be from 350 to 710 c. c.

In case the mechanical treatment in the ball mill is continued to a degree of gelatinization and for the purpose of doing work ordinarily left for the beater and Jordan, the figure of1'l10 c. c. might be carried on up even to complete gelatinization. However, if the duration of the ball mill treatment is limited to not over one-half an hour the washed fibre will show within the test range as outlined above.

I am producing a certain type of product in any. case, although this method may permit me to carry the mechanical treatment to a point ,whicli. is-.l..ordinarily accomplished ,only in the .papermill by means of heaters and Jordans or by means of some other-type of hydrating ma- In comma alpractice we will always be making clefi nite grades or qualities of product and we will'therefore in commercial practice always be comparing the concentrations required to produce'a given drasticity of treating solution which may be used to produce the grade of product which we may have under consideration. Thewater only, without any ball mill treatment. The second sample was treated with water only using,

ball mill treatment and shows the slowing effect of the ball mill treatment with no reactive chemical present. The third and fourth items show the freeing effect of the ball mill in the presence of a reactive chemical, for the 10 minute and 20 minute periods of time. The gelatinization in the 20 minute experiment of the third example indicates-more curling taking place than in the 10 minute experiment using the'same strength of treating chemical.

Treating solu- Bottom Duration oi Mechanical tion (concenoutlet freetreatment nation) method new 1 10 minutes.. Water Agitation..- 638 c. c. 2 10minutes W for Ballmill .c. 3 20minutes-. .c. 4 10 minutesc. 5 10minutes-...{ N .c. 6 l0 minuies- 10% NaOH Ball mill 450 c. c. 7 10 minutes 10% Na Ball mill 575 c. c. 8 15 minutes- 5% NaOH..- Ball mill 600 c. c. 9 10 minutes 21% NaOH Ball mill 412 c. c. 10 10 mmutes-. m N81s-- all mill 420 c. c. g :3 rmniigugnu 2g, gazgfiun Ball mill 710 c. c.

u a I NB }Bali 111111 565 c. c. 13 10minutes.--. ff fl g- }Bal1mili 4817c. c.

- east-"- 14 10 minutes 14 oNalco-i: }Ballmill 625 c. c.

It is to be noted that the kraft pulp tested in this particular case without the use of any caustic at all has a freeness of only 718 whereas and used in the mechanical treatment in the. ball producing curling or crimping of finished pulp is regarded as novel.

Reference is made to my copending application Ser. NO. 558,185, Aug. 19, 1931 for Method of producing absorbent or resilient felt which concerns sodium sulfide fibre curling treatment.

Reference is also made to my copending application Ser. No. 558,826, filed Aug. 22, 1931 for Method of producing absorbent or resilient felt in which a fibre curling treatment is disclosed involving the use of some of the chemicals herein 30 referred to.

My invention involves recognition of the fact that when a cellulosic fibre is bruised at a particular point, the bruised portion of the individual .will nullify .these "physical characteristics obtained bya relatively short treatment. The balls must be carried well up in rotation in the bruising ball mill, so'that the maximum fall will be obtained and a clear cut bruise will be effected.

A rod mill isless effective than a ball mill, as it may over-bruise some of the fibres. Also a hammer mill of some sort-might be used as the bruising apparatus.

It will be apparent that my invention is not confined to a definite mechanical device, nor to simultaneous treatment .or impregnation with chemical and bruising. The fibres may be saturated with the treating solution and bruised in a ball mill or a shredder after saturation or they may be bruised in water suspension and this water displaced by the treating chemical, a

, mechanical bruising treatment.

It will be understood that where, in the specification and claims, bruising and treating the fibres is referred to, this is to be broadlyconstrued to include simultaneous bruising and treating, or first bruising and then treating, or first treating and then bruising. It is apparent that in the latter case the accentuated treatment or difierential reactivity cannot take place until after the saturated fibre is bruised.

The length of time required is dependent upon the size of the mill or bruising apparatus and the rate of feed of the material.

In a small batch mill, from 8 to 15 minutes has been required to produce the desired partial bruising effect, using balls as the bruising media. As a maximum permissible time for the bruising treatmentapproximately one-half hour N is may be stated, it being understood that this can only be roughly determined in view of the other factors to be considered, such as the size of the mill and the rate of feed.

The quality of the resulting product will be varied by varying the duration of treatment, the temperature, and the strength and reactivity of the treating solution.

With a 1 inch steel ball and a dropof approximately 14 inches, and a pulp suspension of 6% density, 15 minutes produce a generally satisfactory product. This suspension may be passed through a pipe, it is semi-fluid and thick, but not non-fluid. My copending application 361,708 filed May 9, 1929, issued as Patent No. 1,830,131 dated Nov. 3, 1931, deals with a nonfluid suspension.

It will be evident that the bruising step is one of degree. If the balls fall too great a distance they will out instead of bruise the fibre. A three foot diameter mill will have an effective fall of about two feet and will give good results on stock of 6% consistency when using 1%" to 2" balls. The denser the consistency of the stock the greater will be the fall required and the larger will be the diameter of the balls required. The extremes of diameters should fall within the limits of inch to 6 inches, the drop from 12 to 120 inches, and the consistency from 1% to 10%.

Additional degree of bruising might go so far as to cause a cutting of the fibres, an efi'ect not ordinarily to be desired. Care should be taken to prevent this in producing the product described. This cutting of the fibres might be caused by the balls being too heavy or falling from too great a distance. In other words, the size of ball and distance of drop is a function of the density of the mix and both of these variables should be worked out to eiiectively bruise the fibre and are therefore a function of the curling as the fibre curls more at the bruised points. The solution strength however bears more relation to the degree of curling than does the bruising. In practice the bruising would be developed to the most effective point for a particular grade and the solution strength for the parinaaior ticular grade desired would be determined byexperiment. I

The ball mill or other bruising means if carefully controlled, gives tangible assistance in curling the fibre, although if continued for any great period of time will have the opposite effect of restraightening the fibres again.

My experiments have been carried out on the following mixtures using a ball mill and approximately 6% consistency of chemical solution mix and pulp.

M ia'ture A Approx. Approx.

Analysis of chemical (dry basis) 0 solution 0 solution Owns/L I am fully aware that solutions approximating the mixturesshown, as well as caustic-lye by itself, have been used for many years for the purpose of reacting with-the acid cementaceous inter-cellular materials which nature has provided to bind together the cellulose fibres of wood and other vegetable substances. 1

It is not the purpose of this invention to perform the preliminary pulp producing operation of neutralizing and dissolving these cementeceous substances but rather to take cellulose fibres which have been previously separated and cleansed by any of the well known chemical processes and to treat these fibres as herein described for the purpose of presenting a product diiferent from that produced by any of the usual pulp producing processes namely, the soda process, the sulfite process, the mono-sulfite process or the sulfate or kraft process. The kraft process which has been in use for a considerable period of time, involves undercooking .various woody materials in a so-called sulfate process. However, the sulfate process is also used to fully cook woody materials, but when so practiced it is not ordinarily called the lrraft process.

Microscopic examination indicates that caustic soda solution causes a thickening of the fibre wall. In the process of thickening, irregularities of the fibre wall are emphasized or magnified, thereby causing the fibre to twist, curl and crinkle.

In the felting or piling up of these twisted fibres countless spaces of capillary function are formed, thereby imparting to thefelted product its commercially valuable characteristics of absorbency, extreme bulk, capability of being impregnated. and resiliency.

' The curled or crimped fibres having marked afilnity for attaching to themselves precipitated waterproofing agents such as rosin, aluminum hydrate, copper hydrate, zinc hydrate, etc. and when so treated that these substances are deposited on the surface of the fibres in insoluble form, a springy, waterproof, relatively non-absorbent product is the result,--a waterproof product which may be compressed and released many times without losing its resiliency.

The ball mill treatment shortens the mechanical treatment necessary in the paper making or felting operation. The ball millmay not be entirely suited to the softer grades of material such as may be produced by other methods, but the'ball mill may be inserted in any type of process'and the material and treating solution passed around it, if desired, as indicated in my copending application, Ser. No. 558,184, filed Aug. 19, 1931, for method of producing absorbent felt.

The balls used in the experiments were partly round cast iron balls .and partly balls with indentations and known under the trade name of Concavex, produced by the Allis-Chalmers Corp.

It has not beeneconomicallypossible, heretofore to treat pulp with caustic lye of over 7% strength of solution.

The diificulty has been in the mechanical handling of the pulp due to a slimy saponaceous resultant material which slows up free drainage through any kind of a screen. By treating the pulpin a non-fluid state, i. e. at least 10% of. fibrous material, as described in my application 361,708, or in a semi-fluid state, this-particular difiiculty has been overcome. However, it has been found that when a mix thicker than 15% of pulp to 85% of caustic solution'is used there is a retarding of the desired kinking, curling, and crimping action. A mix above this density requires .a caustic solution of increased concentration in order to secure the desired curling effect. when a thinner mix than the above mentioned 10% fibre mix, is used, the economic difiiculties and the'slime and washing difiiculties are encountered .on account of the slowness with which the caustic lye solution'drains from the pu p- Thin pulp drains more slowly than thick pulp because in a thin suspension not only do the fibres pack in closely but any materials in suspension such as hemi-celluloses are floated into position between the fibre interstices and pack more firmly therein.

The present process overcomes washing dimculties.

By using a weak solution of caustic lye. less than 7% concentration, or a less drastic treating chemical than caustic lye, even in concentrations greater'than 7%, the difii'culty in washing due 'to sliminess is not encountered, and for this rea-- son'a semi-fluid or slushtreatment can be carried-out economically andwithout undue washingilifiicult'ies.

Reference is made to my copending application Ser. No. 558,184, filed Aug. 19, 1931, for Method of producingabsorbent felt. in which I disclose a mechanical method for handling fibres treated with solutions in concentrations greater than 7%. M

A definition of slowness or "freeness" of cellulosic fibres is the degree of hydration or water holding power" as measured by the rate at water drains away from a sheet or mass of thefibres. when the fibres are ow the water holding power is great with slow drainage, and conversely when'the fibres are free, the water holding power is slight with rapid drainage. This increased water holding power or slowness characteristic may be: (1) From chemical cause.

(2) From mechanical cause.

(3) Resultof chemical or mechanical gelatinization.

(4) Result of chemical or mechanical shortening or straightening of fibres, producing dense or non-porous felted product.

(5) Result of chemical or mechanical kinking, curling or crimping of fibres. a

(6) Combination of any or all of above.

If there should be complete internal and external gelatinization of the entire length of the individual fibres, by the mechanical and physicochemical action, the freeness willbe substantially reduced and slowness will be increased. Prolonged mechanical treatment produces this complete gelatinization and consequent slowness.

The present invention avoids this by limited localized treatment maintaining .i'reeness at a maximum in the production of a grade of product in which freeness is desired. I

However, itis understood by those skilled in the art of manufacturing absorbent and saturating papers and various kinds of felts that certain grades of material require more inherent density of product than others, and as this density is ordinarily produced by a slowing or a partial gelatinization of the fibre mass before forming it into a sheet, I have found that by controlling the intensity of the mechanical treatment given to my product during the process of. manufacture, that the density of the final product may be controlled and the required gelatinization more quickly attained when the mechanical treatment is carried out in the presence of the 116 treating chemical, than when the gelatinization or slowing of the product is carried out mechanically after washing'out the treating chemical. Therefore, for certain grades I prolong the me-. chanical treatment and obtain a desired curling 13 and slowness in far less total time and with less than half the mechanical equipment than as if the two operations of curling and mechanical slowing or gelatinization were notcarried out simultaneously.

In fact, the invention maybe said to involve the provision of a mechanical bruising means for accelerating the phvsico-chemical curling action of I the treating agent, by partial bruising of the'fibres in a limited time, thereby rendering the fibres more vulnerable at the bruised points and causing them to twist or curl about those points, or by mechanically gelatinizing or producing a gel on the surface of the fibres, which gel surface is particularly reactive or susceptible to the physicochemical action of the treating solution, thereby causing the accelerated curling. 'lhis mechanical gelatinization in the ball mill for a controlled time to produce the reactive gel surface on the fibres, may be performed prior to or as a concomitant of the treating with the curling agent- In the treatment of cellulose fibres, a purifica-' tion has been accomplished by the use of caustic or alkalis of less than 7% concentration, but very 5 curling of the fibres with use of less drastic treating solutions at localized bruised points.

' W discovery indicates that the fibre after being bruised is more vulnerable at the bruised point than it is at other points along its length and that less drastic solutions may be used, whether less drastic because of greater percentage of solvent or because of the use of a less active or more inert chemical. Other conditions being unchanged, a certain degree of curling may be attained which would not be attained were it not for this mechanical focal fibre bruising. The kneader process does not bruise the fibres; it simply rubs one fibre against the other in a dense mass. The ball mill or other mechanical bruising contrivance actually hits a blow at a focal point on the fibre at a time when the fibre is resting against a substantially non-yielding body.

Any type of equipment which cause the fibre to be bruised between two hard surfaces in the presence of water or a water solution will cause this gelatinization.

Among these difierent types of equipment for producing gelatinization, are the following:-

Ball mills, rod mills, pebble mills, beating engines, Jordan engines, bruising engines, vemical hydrator, attrition mills, hammer mills, roller mills and various types of shredders too numerous to mention. The-ball mill is only one of several devices in which my method of producing the mechanical gelatinization may be performed.

I have found that the apparatus and method of conducting and by-passing the treating solution, disclosed in my copending application 361,708, filed May 9, 1929, may be used to advantage in a sulfate or kraft wood'pulp treatment, using the by-pass arrangement shown therein for the purpose of producing an absorbent felt. While the kraft liquor is not as drastic at a given percentage strength of solution as is soda pulp liquor, this is partially or wholly-compensated for by the ball mill bruising treatment, described herein. In applying the bypass feature of application 361,708 to the present invention, the treating solution for the ball mill or other bruising apparatus would be by-passed thereto as to the impregnating hieader shown in 361,708.

Where caustic lye is used as the treating solution, I may remove it or separate it from the pulp by either pressing, centrifuging or by water displacement.

Caustic lye as herein referred to is of broader scope than caustic soda in that it may be a regenerated alkali and may contain certain other alkali than caustic soda, such as caustic potash, sodium or potassium carbonates, all of which are alkalis having the same general chemical reactions as caustic soda. It will be understood, however, that wherever caustic lye is referred to, caustic soda or any equivalent alkali having the same general reactions is to be regarded as disclosed in that connection.

It is not intended to limit the invention to the specific illustrations given in the specification by way of example, nor to any fixed limits of solution concentrations or other factors entering into my method, as it will be apparent that these may be considerably varied within the'scope of the invention.

I claim:

1. .The hereindescribed process of accelerating the kinking, curling, and crimping of finished or prepared cellulosic fibres consisting in bruis- I ing the individual fibres at one or more p ints on the length of the fibre, and treating the fibres with a physico-chemically reactive treating solution, thereby causing selective or pronounced reactivity of the treating solution at the bruised points, and consequent accelerated curling of the fibres.

2. The hereindescribed process of accelerating the kinking, curling, and crimping of finished or prepared cellulosic fibres consisting in. partially .bruising the individual fibres, and treating the fibres with treating solution, thereby producing differential reactivity of the treating solution on the body of each 'of the partially bruised fibres, and consequentaccelerated curling of the fibres.

3. The hereindescribed process of accelerating the kinking, curling, and crimping of finished cellulosic fibres consisting in subjecting the fibres to a bruising action for a length of time such that the individual fibres will be only partially bruised along the length thereof, and treating the fibres with ,a physico-chemically reactive treating solution, thereby producing difierential reactivity of the treating solution on the body of each of the partially bruised fibres.

4;. The hereindescribed process of accelerating the kinking, curling, and crimping of finished cellulosic fibres consisting in partially bruising the individual fibres, and substantially simultaneously treating the fibres with treating solution, thereby producing differential reaction of the treating solution on the body of each of the partially bruised fibres, and consequent accelerated curling of the fibres.

5. The hereindescribed process of accelerating the kinking, curling, and crimping of finished cellulosic fibres consisting in subjecting the fibres to a bruising action for a length of time such that the fibres will be only partially bruised along the length thereof, and substantially simultaneously treating the fibres with a physicochemically reactive treating solution, thereby producing differential reactivity of the treating solution on the body of each of the partially bruised fibres.

. 6. The hereindescribed process of kinking, curling, and crimping finished cellulosic fibres ,consisting in partially bruising the individual fibres, and treating the fibres with treating solution of such reduced drasticity as to aifect but slightly the unbruised portion of the fibres but which will produce pronounced reactivity at the bruised points and consequent curling of the fibres.

7. The process according to claim 3 in which said treating solution consists oi caustic lye solution substantially less powerful than caustic lye 01 a strength which would be required alone, i. e. without the bruising, to produce a. given degree of kinking, curling and crimping of the fibres as measured by freeness and absorbency.

8. The process of claim 3 in which said bruising action is continued for a length oi time within one-halt hour. v

9. The process of claim 3 including carrying out said bruising action by subjecting the fibres to the action of balls in a ball mill.

10. The process 01 claim 3 including carrying out said bruising action by subjecting the fibres to the action" of balls in a ball mill, and dropping kinking the fibres according to claim 1, including inization and slowing of the pulp mass necessary for the proper felting of the desired felt product.

12. The method of claim 1 in which said treat-- ing solution is less drastic than causticlye treating solution which alone, i. e. without the bruising, would produce the kinking and comprises partially spent saponaceous liquors.

l3.' The method of claim 1 in which said treating solution is less drastic than caustic lye treating solution which would-be required of itself, 1. e. without the bruising, to produce the desired kinking and comprises spent or partially spent saponaceous liquors fortified with fresh reactive chemicals such as caustic lye ,or less drastic chemicals than caustic lye such as sodium sulfide.

14. 'I'he'method of claim 1' in which said treating solution is less drasticthan caustic lye treating solution which would be required of itself, i. e. without .the bruising, to produce the ,desired kinking and comprises partially spent saponaceous liquors, and in which said bruising action is carried out by subjecting the fibres to the action of the balls in a ball mill.

15. The method ofclaim l including carrying out the bruising of. the fibres in a water suspen-" sion and subsequently carrying out the physicochemical treatment of the bruised fibres by displacing the water by the treating solution.

16. The method of claim 1 including first treat- .ing the fibres by saturating the fibres with treating solution and subsequently bruising the saturated fibres.

17. The process of claim 3 in which said bruising action is continued for from 8 to 15 minutes.

18. The process of claim 3 in which said bruising action iscontinued for from 8 to 15 minutes and is carried out by subjecting the fibres to the action of balls in a ball mill, and dropping the balls in the bruising treatment onto the fibres through a drop of from 12 to 120 inches.

19. The process of claim 3 in which said bruising action is continued for from 8 to 15 minutes and is carried out by subjecting thefibres to the action of balls in a ball mill. and dropping the balls in the bruising treatment onto the fibres through a drop offrom 12 to 120 inches, the pulp suspension containing said fibres being of from ing solution of the same percentage solution or.

concentration.

22. The process of claim 35 in which said treating solution is less drastic than caustic'lye treating solution of about 7% to 24% concentration.

, 23. As a new article of manufacture, a felting machine product having bulk and absorbency and comprising constituentnifferentially bruised and focally treated individual fibres, said product havi& a freeness of 350 c. c. to 'i10 c. 0. using 5 liters of mixture and 25 grams of bone-dry pulp, using ja bottom orifice of 9/64 opening method consisting in subjecting fin- 24. The

fibrous cellulosic pulp to me-.

ished or prepared chanical bruising treatment such as to render the cellulose fibres more reactive or responsive to a curling agent, and treating the fibres with a curling agent.

25. The method accordingto claim 24 in which said mechanical treatment is such as to partially bruise the individual fibres at one or more points on the body thereof thereby causing focal reactivity of said curling agent at the bruised points and consequent accelerated curling of the fibres.

26. The method according to claim 24 in which said mechanical treatment is efiected in a ball mill, and controlling the time of treatment in said ball mill so that the individual fibres are only partially bruised on the body thereof.

27. The method according to claim 24 in which said mechanical and curling agent treatments are effected substantially simultaneously.

28. The method according to claim 24 in which said curling agent is of less drasticity than the curling agent which without the bruising would be required to produce of itself the same degree of curling.

29. The method according to claim 24 in which said mechanical treatment is such as to produce a reactive gel upon the surface of the fibres, said curling agent acting with accelerated reactivity 1J0 same, said curling agent being of less drasticity 2.1;-

than the curling agent which would otherwise be required to produce of itself the same degree of curling.

31. The hereindescribed process of'acceleratging the kinking,- curling, and. crimping of finished or prepared cellulosic fibres consisting in mechanically gelatiniz'ing the fibres for a sufiicient time to produce a gel upon the surfaces of the fibres, said gel being of increased reactivity to curling agent, and treating said reactive gel surfaced fibres with curling agent.

32. The method of claim 31 in which said curling agent may be of reduced power or drasticity, as compared with the curling agent which would otherwise berequired to produce of itself' the same degree of curling.

33. The method of claim 24 including forming the curled fibres into an absorbent and resil-, lent felted product.

- 34. The hereindescribed process of kinking,

curling and crimping finished cellulosic fibres consisting in partially bruising the individual fibres, and treating the fibres with a treating solution of such reduced drasticity as would not of itself, 1. e. without the bruising, produce the ,desired kinking butv which will produce pro-.

nounced reactivity -at the bruisedpoints and consequent curling of the fibres. 35. The hereindescribed process of accelerat- I ing the kinking, curling, and crimping of finished or prepared cellulosic. fibres consisting in partially bruising the individual fibres, and treating the fibres with treating solution, thereby producing differential reactivity of the treating solution on the body ofeach of the partially bruised fibres, and consequent accelerated curling of the fibres, said treating solutionbeing caustic lye of such reduced drasticity as would not of itself, 1. e. without the bruising. produce the desired kinlclngbut which will produce pro- 150,

nounced reactivity at the bruised points and consequent curling of the fibres.

36. The hereindescribed process of kinking, curling and crimping finished cellulosic fibres consisting in partially bruising the individual fibres, and treating the fibres with a treating solution of such reduced drasticity as would not of itself, i. e. without the bruising, produce the desired kinking but which will produce pronounced reactivity at the bruised points and consequent curling of the fibres, said treating solution'being a. solution of at least one material selected from a group consisting of sodium sulfide, sodium carbonate, sodium chloride, sodium sulfate, sodium sulfite, sodium phosphate, sodium nitrate, zinc salts including zinc chloride cuprammonium compounds, copper compounds including copper salts, aluminum saltslammonium hydrate, calcium hydrate, calcium chloride, soaps, spent saponaceous liquors, and partially spent saponaceous liquors, which saponaceous liquors are fortified by fresh reactive alkaline material.

3'7. The hereindescribed process of curling or kinking felting fibres which have been prepared by removing cementaceous material therefrom consisting in partially bruising the fibres at a point or at segregated points along their lengths treating the bruised fibres with a physicochemical solution to produce the kinking and subjecting the fibres to a further bruising action in the presence of physico-chemical reactive solution to produce gelatinization of the fibres necessary for the felting of the product.

memoir 38. A process according to claim 37 in which the bruising is performed by balls in a ball mill.

39. A process according to claim,37 in which the further bruising action for gelatinization is performed by the same means which is employed in the kinking operation.

40. A method according to claim 1 in which the bruised fibres treated with the physico-chemical solution are gelatinized with a change in the suspending liquid.

41. The hereindescribed process of kinking, curling and crimping finished cellulosic fibres consisting in partially bruising the individual fibres, and treating the fibres with a treating solution of such reduced drasticity as would not of itself, i. e. without the bruising, produce the desired kinking but which will produce pronounced reactivity at the bruised points and consequent curling of the fibres, said treating solution being a solution of at least one material selected from a group consisting of sodium sulfide, sodium carbonate, sodium chloride, so-

dium sulfate, sodium sulfite, sodium phosphate,-,

sodium nitrate, zinc salts including zinc chloride, cuprammonium compounds, copper compounds including copper salts, aluminum salts, ammonium hydrate, calcium hydrate, calcium chloride, soaps, spent saponaceous liquors, and partially spent saponaceous liquors.

JOSEPH E. PLUMSTEAD.

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