US1941958A - Acglutinant - Google Patents

Description

Patented & Jan. 2, 1934 UNITED STATES AGGLUTmANT Willy Stelkens, Cologne, and Richard Miiller,

Mannheim, Germany,

assignors to C.

Boehringer & Soehne G. m. b. H., Mannheim- Waldhof, Germany No Drawing. Application August 9, 1930, Serial No. 474,301, and in Germany August 12, 1929 13 Claims. 8717) Our invention refers to agglutinants, more especially such as are insoluble in water and have the form of a powder or a folia, which consists largely of a cellulose derivative, such as for instance a cellulose ester, acetyl cellulose, nitro cellulose or the like. An agglutinant of this kind, if inserted in dry condition between two pieces of leather and heated or moistened with a solvent for the agglutinant or both, will cement the two pieces together.

We have now ascertained that the time required for obtaining a full effect of the agglutinant can be considerably reduced and at the same time the tearing resistance can be greatly increased if, instead of using a powder or folia formed of one or a plurality of ordinary plastic agglutinants, a mixture is used, which is composed of constituents having difierent, well defined characteristics.

We have found that a ready softening and setting and a permanent adherence of the surfaces to be cemented can be obtained if the agglutinant is composed of at least two cellulose derivatives, each of which has the adhesion characteristics of an agglutinant, under the influence of a solvent or swelling medium or of heat or both, not only as far as the surfaces to be cemented are 'concerned, but also with regard to the other component or components constituting the composition, while at the same time differing, as far as these adhesion characteristics are concerned, from one or several of the other components (if more than two components are present). While it is desirable that the solidity of fixation obtained be as great as possible in all components, we have found it advantageous that they differ in respect of the period of time required for swelling or softening and for setting.

Agglutinants composed of a plurality of components of different character will react difierently towards solvents as well as upon heating. That component, which swells or softens more readily, will quickly create a bond between the surfaces to be cemented, while another component, which swells or softens less readily and forms with the solvent a solution of higher viscosity, will act like a lattice or frame-work,- first whether they are chemically well defined comoffering a mechanical support to the more readily swelling and softening component or filler, preventing deliquescence thereof, but thereafter gradually swelling also and, in doing so, gradually absorbing the cementing layer of the other component into its own cementing layer and uniting with it. v

The term "component, as here used, is meant to include homogeneous substances, no matter pounds, such as for instance cellulose esters or ethers, or mixtures, such as celluloid or other cellulose derivatives combined with softening means to form homogeneous masses.

Taking this into account, agglutinants according to the present invention, which form binary or higher mixtures, may for instance be composed of celluloid and nitro-cellulose or of celluloid and gelatinized acetyl cellulose or of two or more kinds of celluloid recovered from nitro celluloses of different viscosity. Gelatinzing, softening and/or dissolving agents may be added, which may facilitate the swelling and softening of one or all components.

The new agglutinants according to the present invention are fit for cementing together materials of the same or of widely diifering character, for instance leather, paper, cardboard, textile materials, wood, metal, glass, porcelain, etc. Shoe soles, doubled webs of fabric, plywood, metallized cable envelopes, insulating layers and non-splintering glass plates can be manufactured wit the aid of these agglutinants.

The selection of the components with respect to their swelling capacity, viscosity etc. so that they can either act as frame-work substances or as fillers, depends upon the nature of the materials to be cemented, upon the pressure and temperature admissible during fixation, upon the requirements of cementing speed and strength and the like, and can be determined in a simple manner by experiment for each individual case.

The following table contains a small number of particularly useful compositions according to this invention.

Framework substances 7 Fillers Soitened by means of Particularly suited for cementing 50 Celluloid waste Nitrocellulose of high viscosity (collodion wool) Acetyl cellulose Nitrocellulose of low viscosity (about 1% seconds) Nitrocellulose of low viscosity N itroeellulose Leather, textile material, paper Leather, textile material, paper Leather, textile materiel, wood Solvents for celluloid The agglutinants according to this invention can be obtained by simply mixing the finely powdered components, which may be used as such or may be converted into foliaa, by compressing the powder to plates or blocks, which are then subdivided into thin sheets or films by planing or otherwise. Foliw can however also be produced by pouring or dissolving and kneading and mill- Example 1 12 parts acetyl cellulose soluble in acetone and 3 parts ethyl acetanilidon the one hand and 12 parts collodion wool and 3 parts ethyl acetanilid on the other hand are dissolved in acetone. The two solutions are first filtered separately and are then mixed. The mixture can be converted into liquid folim by pouring, which can be used with solvents for cementing leather, cardboard, textile materials or the like together.

Example 2 12 parts transparent celluloid waste are mixed with 8 parts of nitrocellulose of low viscosity, such as is used for instance in the manufacture of lacquers applied by atomization. To the mixture is added a solvent capable of dissolving both constituents and it is then converted according to one of the methods used in the manufacture of celluloid, into foliaa, which preferably serve for cementing'leather, textile materials and paper together without the application of heat, a suitable solvent being used.

The term softening medium used in the claims is intended to include also heat, solvents and swelling agents.

tics of an agglutinant with regard to the other.

component as well as to the material to be cemented, but differing from the other component in respect to the rate of softening.

2. As a new product, a solid agglutinant being a mixture of acetyl cellulose, collodion wool and ethyl acetanilid.

3. As a new product, an-agglutinant in solid form comprising a plurality of components of different softening properties intimately mixed with one another and each component, when acted upon by a softening medium, possessing the characteristics of an agglutinant with respect to theothers, at least two of said components being cellulose derivatives.

4. The product of claim 3 wherein said cellulose derivatives are cellulose esters.

5. The product of claim 3 wherein at least two of said components are celluloid having different softening properties.

6. The product of claim 3 wherein one'of' said components is celluloid and another is nitrocellulose.

7. The product of claim 3 wherein one of said components is celluloid and another is low viscosity nitrocellulose.

8. The product of claim 3 wherein the said solid agglutinant is in the form of foliae.

9. The product of claim 3 wherein the said solid agglutinant is in pulverulent form.

10. As a new product, an agglutinant in solid form comprising at least two cellulose ester components of difierent softening properties inti mately mixed with one another and possessing, when acted upon by a softening medium, the characteristics of agglutinants with respect to each other, at least one of said esters being combined with a plastifying agent.

11. The product of claim 10 wherein said cellulose ester components are nitrocellulose.

12. The product of claim 10 wherein at least two of said cellulose ester components are nitrocellulose and one of said components is combined with a plastifying agent.

13. The product of claim 10 wherein at least two of said cellulose ester components are nitrocellulose and one of said components is combined with a greater amount of a plastifying agent than another of said components.

' WILLY STELKENS.

RICHARD MULLER.