US1514655A - Fiber board and process of manufacturing the same - Google Patents

Description

enemies Nov. 11, 1924.

UNITED STATES 1514555 PATENT oFFIcE.

ALBERT L. GLAIP, OF DANVERS, MASSACHUSETTS, ASSIGNOR TO BEGKWITE, MANU- rnc'runme comm, or nosron, MASSACHUSETTS,

A. CORPORATION OF MAINE.

FIBER BOARD AND PROCESS OF MANUFACTURING THE SAME.

Ho Drawing.

To all whom it may concern:

Be it known that I, ALBERT L. CLAPP, a citizen of the United States, residin at Danvers, in the county of Essex and tate of Massachusetts, have invented new and useful Improvements in Fiber Board and Processes of Manufacturing the Same, of which the following is a specification,

This invention has for its objectto rovide a new material which is capable o being formed into a hard horny mass or into sheets of any desired thickness, and a process of making the same. I

I have discovered that, if animal matter such, for example, as tanned leather, ground bone or dried fish scraps are digested under heat and pressure with a large proportion of caustic alkali in the presence of cellulose fiber, a solution is formed which permeates the fibers, and which may be subsequently precipitated therein by the employment of a precipitating agent such as a metal salt, and that this material may be molded, 'or formed into a single web or a composite sheet, and that the product is strong and more or less water-repellent. Thus I may produce a paper of high tensile strength, or a hard inflexible board, by varying the proportions of the components and the process 0 manipulating the fibrous mass.

For forming a. material somewhat like fiber board or leather board, one may proa rapidly than be ore.

ceed as follows :-Into a digester, which may be closed, are introduced, say, 1000 pounds of cotton fibers (e. g., linters or cotton waste), and about 300-500 pounds of comminuted tanned leather (or ground bone, or

such .dried fish scraps as are ordinarily used for fertilizers), and about 15 pounds of caustic soda and enough water to submerge the foregoing ingredients. -The digester is closed, steam is injected from time to time until a pressure of about pounds is reached, and the cooking is continued for about four hours more or less. The tannic acid in the leather is neutralized and; the leather breaks down into solution, and the solution permeates or impregnates the cotton fibers. The fibers because of the cooking, are rendered ca able of hydrating more The contents of the digester are now withdrawn, and are placed in abeating engine with added water to a beating operation for about five hours.

oipitating agent,

Application filed June as, 1920. Serial no. 391,163

Then I add to and beat into the mass 9. pree. g., aluminum sulphate, lead acetate or other suitable metal salt. This product is now introduced into a wet cylinder paper machine, and the fibrous mass is formed thereon in superposed convolutions until an encircling composite sheet of the desirable caliper is obtained, whereupon the sheet is slit, flattened, dried, and, if desired, compressed under high pressure. Instead of being formed into a web, the water may be squeezed from the mass, and the latter molded in suitable molds under pressure.

It is quite evident that, instead of using cotton fiber, terials, such as mechanical wood pulp or chemical wood pulp, e. g. sulphite or soda pulp, or the screenings of such pulp. For

example, a very strong and tough wrapping with a metallic salt in a beating engine, sub-,

sequent to the beating of the pulpy mass,

f then forming a sheet therefrom by any suitable sheet-forming paper machine. A sheet I may use other cellu'losic maso formed possesses greater strength than paper of the same cali r formed in the usual manner from sul ate. pulp. For the sulphate pulp, referre to in this example, I may substitute rag fiber, or cotton linters or waste, or ground wood or soda or sulphite pulp, or them equivalents.

The digestion of the tanned leather -('or its equivalent) under high pressure and temperature with a large proportion of caustic soda, results in. a solution, which, according to Grahams test, is non-colloidal, and thus is capable ofpermeating individual fibers. The an' lution, 1s precipitated into waternsoluble precipitate, in gelatinous form which dries into a hard colloidal mass.

What I claim is 1. A process which comprises digesting cellulosic material, animal matter and a caustic alkali with heat and pressure, and then precipitating the animal matter in solution. p

2. A process which comprises digesting cellulosic material, animal matter and a then precipitating the tion with a metal salt.

emma caustic alkaliwith'heat and pressure, and

animal matter in solu- 3. A process which comprises digesting 'cellulosic material, animal caustic alkali with he ing the digested mass matter and a at and pressure, beatwith water, and then precipitating the animal matterin solution with a metal salt.

4. A process which comprises digesting cellulosic material, animal caustic alkali with he ing the digested mass matter and a at and pressure, beatwith water, then precipitating the animal matter in solution with a metal salt, and finally forming the pulpy 15 mass into a sheet of desired thickness.

5. A fibrous material, the fibers and interstices of which contain an insoluble colloidal precipitate, precipitated by a metal salt from that noncolloidal matter derived from the digestion of leather or the like with a caustic alkali. ,i

In testimony whereof I have aflixed my signature. i

ALBERT L. CLAPP.