US1529299A - Felt and process of making the same - Google Patents

Description

Patented Mar. 10, 1925.

UNITED STATES PATENT OFFICE.

ALBERT L. CLAPP, OF DANVEBS, MASSACHUSETTS FELT AND PROCESS OF MAKING THE SAME.

No Drawing. Application filed May 10v To all 20710! if 1/14/ corny/n Be it known that I, ALBERT L. Curr, a itizen of the United States, residing at Danvers, in the county of Essex and State of h'fasswlmst-tts, have invented new and useful Improvements in Felt and Processes f Making the Sallie of which the f llowing is a specification.

This invention has for its object to pl duce a compressible resilient felt, capable of use in the manufacture of gun wads insulation for railway cars, ice houses refrigerators and the like. and which is water-resistant and which moreover may be produ ed on a paper-malring machine such as a wet machine so-called.

I first start with a cellulosic material. referably cotton linters so-called.but in ion of cotton linters I may use jute, rags or other suitable material. I load a beating engine with approximately 600 pounds of the cellulosic material, e. cotton linters; and, adjusting the roll to t e bed plate beat the raw material with suficient water to ensure free circulation until the raw material is well beaten without material hydration. This takes ordinarily in the neighl orho d of 4 hours more or less and effects a disintegration of the fibers. To the contents of the eater tub are added about 50 pounds of rosin size and the beating is continued until the rosin size is thoroughly incorporated in the mass usually for about 1 hour. Then I add preferably aluminum sulphate in excess of that needed to precipitate the rosin size in the form of aluminum resinate. Ordinarily it would take about 25 pounds f alum to preci itate 5 pounds of rosin size. but preferab y I add about 50 pounds of alum, thus providing an excess of .25 pounds. The beating: is continued for about 1 hour until the aluminum resinate is recipitated on the fibers of the mass. The water roll is then raised and about 600 pounds of cattle or goat hair (dry weight) derived from tanneries is added to the beater. Th adjustment of the roll is such that. when the beater is again started in operation. the contents of the tub are thoroughly intermixed and the hair is brushed without cutting or hard beating. This may continue for about 1 hour. Wet hair from the tannery may be used or hair after it has been dried. In any event, such hair has usually mixed therewith more or less lime. (It is for this reason that I employ an excess of alum in the first sizing 1922. Serial No. 559,960.

of the mass. the excess alum serving to neutralize the lime and form soluble salts which wash ut with tile water.) The mass is then again sized bv the additi n f rosin size and sutlicient alum to react therewith for the precipitation of aluminum resinate. For this purpose. I may add for example 30 pounds of rosin size and 10 pounds of alum. the latter f course being added after th rosin size has been thorcuighlv intermixed with the mass. The amounts f rosin size added at these different times to the mass of course may be variedv After the beating and brushing operaticuis. the stock is then she ted n a wet machine until the mat rial on the make-up roll is of the desired thickness or caliper. The material is then stripped from the roll andis dried fiat, after which it may be passed through calender rolls to compact the sh et slightly and to finish the surface of the sheet.

With not so gum] results. inst ad of (lOllle sizin; operation durin; the beating of the stoclt. the hair may be added to the beater after the tellulosi material has been properly beaten and the rosin size added after the hair has been thoroughly intermixed with the cellulosic material during the brushing operation. Even in such case. ecause of the presence of lime in the cattle or goat hair. I use alum in excess of that necessary to react with the rosin size. In su h case after the cotton linters have been beaten for, say. 4 hours with hard beating. the r lls may be lift d and an equal amount f hair added. The beater is then set in operation and the mass is circulated and intermixed without cutting th hair for about 1 hour I may then add 50 pounds of rosin size and c ntinue the brushing operation for 1 hour. after which pounds of alum may b added and the beater continued in operation for another hour. Prefera ly. when the alum is added. the roll is still further lifted to eflect m rely the circulation and intermixing of the components of the mass without an actual beating or brushing operation. since the final operation of the beater is merely to secure a thorough intermixing of all of the components of the stock. The pulp is th n sheeted as previ usly described.

In some instances instead of using cotton linters or jute r rags, I may substitute for all or a portion thereof such cellulosic material as chemical wood pulp -or waste manila, rag or mixed papers,-or sulphite, sulphate or ground Wood screenings,this depending upon the particular use to which the felt is to be subjected.

The final product is water-resistant, resilient and slow burning. When out into blanks of the proper size, it may be used for the manufacture of dust guards, such as employed in railway car journals; or, as previously stated, it is excellent as a non-con- (luctor of heat and lends itself to use as an insulation for ice houses, railway cars, refrigerators, etc.

When cotton or other equivalent fiber is used as the initial or starting material, it must be beaten to the required degree of fineness, as otherwise, on the addition of the hair which is only brushed, a stock would be produced which would be too free and more or less lumpy and would not properly form or felt on the cylinder mold.

What I claim is:-

1. A soft compressible and resilient waterresistant felt comprising hair and cellulosic material in substantially equal parts in interfelted relation and containin a waterproofing precipitate, said materlal having the charactertistics of one formed on a paper-making machine.

2. A method of producing a soft compressible water-resistant resilient felt which comprises beating a cellulosic material, adding and intermixing therewith an approximately equal amount of tanners hair without materiall cutting the hair, adding rosin size and eient alum to precipitate the rosin size and to neutralize lime contained in the hair, and felting and sheeting the stock on a paper machine.

3. The herein described method of producin a water-resistant resilient com ressible felt, which comprises beating cotton linters'to disinte rate the fibers, then adding rosin size an alum in excess of that required to recipitate sodium resinate from the size, adding and intermixing waste tanners hair with the stock without materially cuttin the hair, the excess alum serving to neutra ize the lime contained in the hair, then adding rosin size to the mass and precipitating aluminum resinate therefrom by the addition of alum, and finally felting and sheeting the stock on a aper machine 4. A method of pro ucing a water-resistant fibrous material, which comprises beating a cellulosic material to effect a disintegration thereof, precipitating a size on the isintegrated fibers, adding and mixing waste tanners hair with the mass to produce a substantially homogeneous mixture, precipitatin a size throughout the mass, and finally s eeting the mass on a paper machine.

In testimony whereof I have afiixed my signature.

ALBERT L. CLAPP.

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