US1673967A - Hair felt and method of making - Google Patents

Description

Patented June 19, 1928.

UNITED STATES 7 1,673,967 PATENT OFFICE.

ALBERT L. CLAPI, OF DANVER S, MASSAGHU SETTS ASSIGNOR T0 BECKWITH MANU- FACTURING COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSA- GHUSETTS.

HAIR FELT AND METHQD 015 l/IdKENG.

Ho Drawing.

resins, gums, etc. of such nature and in such proportion as-inay be desired to give it characteristics suitable for roofing, flooring, shoe stiffeners, or other products composed of saturated fibrous material.

The principal difficulty found in the use of large quantities of long hair suc i as that comprising goat and cattle hair as it comes from tanneries is the strong tendency of the hair to become matted and lumpy in the machine so that uneven felt having weak spots therein is produced, and in attempts heretofore to produce a felt containing such hair, it has been necessary to .set the beater roll down so hard in beating out these lumps, that most of the hair has been cut or broken and consequently in the felt the hair was relatively short. The more long hair that can be incorporated in the felt, however, the more porous the product and the stronger and tougher when saturated.

l have discovered that considerable quantities of hair may be successfully used to produce substantially uniform felt containing the hair in its original length, if in connection therewith some agent is used to in dividualize the hair while the furnish is being prepared for felting. One such material which may be employed is short hair treated with caustic soda to form a slimy mass which coats the individual long hairs and permits them to slip on each other. As an example of the way in which this may be used, the procedure ma be as follows: twenty parts by weight 0 rags or other cellulosic material, thirty parts of goat or cattle hairas it comes. from the tannery, and six parts of caustic soda are placed in a beating engine with suflicient water to perunit circulation, and are beaten with the beater roll down hard until the hair is quite short and the mixture forms a slimy mass. Fifty parts of long goat or cattle hair are then added and the mixture beaten out to form a homogeneous mass with the beater roll raised just sufiicientl so that the hair last added is kept long ut is combed out Application filed September 12, 1923. Serial Ito. 662,226.

and coated with the other material. If the individualizing agent is not used it is impossible to maintan the major porton of the long'liair in its original length and yet separate it suificiently to felt properly on the paper machine. By theuse of this individiia'lizing agent, however, and by careful adjustment of the beater-roll, the hair may becombed out and coated with the individualiring material while maintained in its original length. Eight parts of alum may then be added to the mxture which causes the slimy gelatinous mixture of short hair and hair wholly and partially dissovled in the caustic solution to he precipitated on the long hair. The stock may then be run into the vat of the paper machine and sheet-ed in the usual manner.

The presence-of the short hair and also the precipitated matter causes the felt to be somewhat more dense than would be the case if they were not present and it also adds materially to the ease with which the stock is handled in the papermachine since they act to prevent the individualized fibers from matting together or becoming displaced after having once been felted in the paper machine, pressure exerted thereon by the various pressure rolls being then inedective tocause displacement of the fibers. This precipitated matter also acts to impart body to the felt much increasing its strength when in dry condition. Practically all the individualizing agent so precipitated is aluminum gelatinous. hydrate. The short hair alone also has some individualizing properties even though it is not completely dissolved by the caustic and the individualizing agent is thus composed of a mixture of short hair and gelatinous slimy material.

In place of the rags, a mixture of rag and sulphite pulp. or sulphate pulp alone may be employed and if it be desired to impart a more open texture to the material this may be effected by adding up to ten parts of woodflour or fine sawdust, preferably before the addition of that portion of the hair which is tobe kept long in the final product. This wood'flour or sawdust causes the stock to be freer and makes the saturating of the product somewhat easier. The quantity of sulphate pulp or other cellulosic ma terial, may be reduced if desired to as little as 10% and when this is done 20% of hair ill iltlt which is beaten up short with the caustic to form an individualizing agent may be employed together with 70% of long hair. A small amount of cellulosic fiber such as rags, chemical wood pulp, or screenings appears necessary in order that the stool: may be caused to run successfully on the paper machine.

The action of the caustic on the short hair is evidently partially to saponify the oil of the short hair fibers and partially to dissolve the hair, and to form a slimy mass which Surrounds and coats the long hairs and causes them to slip by each other and become thoroughly individualized and evenly distributed throughout the stock in the beater.

Hair as it comes from the tanneries is usually matted and lumpy. During the process of de-hairing hides in the tanneries lime is usually used and the hair as it comes from the de-hairing operation is wet and mixed with lime. As this mixture does not keep, it is the usual practice to wash out the lime and then dry the hair. Some lime may, however, be left in the hair in its dry state. The resence of such lime, when carrying out tlieprocess of this invention does no harm, but indeed is often of distinct value since a cheaper grade of caustic may be used, the cheaper grades of caustic usually containing a considerable portion of sodium carbonate which is causticized by the lime into caustic soda. During this action the lime itself is converted for the most part into insoluble salts which are retained by the gelatinous matter precipitated by the alum, and act as a filler for the final product. Unwashed hair may thus be used successfully in the process of this invention with the cheaper grades of caustic when itv can be procured sufficiently promptly from the tannery to avoid spoiling, but washed hair may be employed with substantially the same results if lime be added to the beater. Where the unwashed hair can be obtained, however, it should be somewhat cheaper than the washed hair.

Having thus described this invention it should be evident to those skilled in the art that various changes and modifications might be made therein without degiirting from its spirit or scope as defined y the appended claims.

I claim:

1. Felt having the characteristics of wet paper machine fabrication, said felt comprising hair of original length, short hair, and cellulosic material.

2. A method which comprises beating out hard a mixture of cellulosic material, hair, and caustic until the hair short: or partially dissolved to a slimy state, then adding long hair, beating out the long hair while ret aining its original length until it is individualized by the mixture, and then felting the stock on a paper machine.

3. The method which comprises individualizing long hair with a mixture containing short and partially dissolved hair, and then felting the stock on a paper machine.

4. The method which comprises individualizing long hair with a mixture containing short and partially dissolved hair reduced to a slimy state, and then felting the stock on a paper machine.

5. The method which comprises mixing long hair and an individualizing agent comprising short hair, and felting the stock on a paper machine.

6. The method which comprises mixing long hair and a gelatinous individualizing agent comprising partially dissolved hair, and felting the stock on a paper machine.

7. The method which comprises mixing long hair with an individualizing agent com prising short hair and caustic, and felting the stock on a pa er machine.

8. The metho which comprises mixing long hair with cellulosic material and an indlvidualizing agent comprising short hair and caustic, and felting the stock on a paper machine.

9. The method which comprises mixing long hair with an individualizing agent comprising partially dissolved hair forming a gelatinous mixture, and felting the stock on a pa er machine.

10. T e method which comprises mixing long hair with an individualizing agent comprising short hair and caustic, precipitating the individualizing agent on the hair, and felting the stock on a paper machine.

11. The method which comprises mixing long hair with cellulosic material and an individualizing agent comprising short hair and caustic, precipitating the individualizing agent on the cellulosic material and long hair, and felting the stock on a paper machine.

In testimony whereof I have aitixed my signature.

ALBERT L. CLAPP.