US2063134A - Casein dispersions - Google Patents

Description

Patented Dec. 8, 1936 PATENT OFFICE CASEIN DISPERSION S Frank G. Uhler, Newburgh, E. I. du Pont de Nemours mington, DeL, a corporation N. TL, assignor to & Company, Wilof Delaware No Drawing. Application February 9, 1932, Serial No. 591,933

8 Claims.

This invention relates to casein dispersions and, more particularly, to dispersions of casein in water and sulphonated fixed or fatty acid oils and to artificial leather prepared from such dispersions.

Heretofore casein has been dispersed in water with the aid of either acid or basic dispersing agents, but a neutral dispersing agent for this purpose has not been known.

Obviously, a neutral aqueous dispersion of casein has many advantages in commercial use over a, dispersion which is distinctly acid or alkaline.

An object of the present invention is the provision of a neutral aqueous dispersion of casein that will form a tough and flexible casein film. A further object is the preparation of artificial leather having a tough, flexible casein surface coating. Other objects of the invention will be apparent from the description of the invention given hereinafter.

The above objects are accomplished according to the present invention by employing sulphonate ed fixed or fatty acid oils as the dispersing agent for casein in water and using a fibrous base sheet with the casein dispersion so obtained to produce an artificial leather.

It was discovered that the sulphonated fixed or fatty acid oils, that is, such oils as castor, coconut, corn, olive, and similar oils, hereinafter referred to as fixed oils rather than fatty acid oils, which latter term might be construed to exclude glycerides of oleic acid and such acids which are not strictly fatty acids, function to give homogeneous neutral dispersions of casein in Water and have the further advantage that, being compounds of low vapor pressure, they function as permanent softening agents or plas-- ticizers in films produced from such dispersions. sulphonated castor oil, commercially known as Turkey red oil, is the preferred dispersing agent and the following specific examples are given to illustrate dispersions employing this agent-Percentages are by weight.

Example 1 Per cent Casein 20.0

sulphonated castor oil 5.0

Water 75.0

The above composition represents the minimum quantity of sulphonated castor oil which has been found to produce a satisfactory homogeneous dispersion of casein in water.

Example 2 Per cent Casein 20.0 sulphonated castor oil 70.0 Water 10.0 5

The above composition represents the maximum quantity of sulphonated castor which will produce a satisfactory homogeneous dispersion of casein in Water. If the sulphonated oil content exceeds this limit, an incomplete dispersion results which is not satisfactory for commercial use.

.The following examples illustrate preferred specific proportions in order to obtain a disper- 15 sion of low viscosity in view of the casein content, clarity and homogeneity:-

Films deposited from the compositions in Examples 3, 4 and 5 possess marked adhesive prop- 35 erties and exceptionally satisfactory qualities in general for the production of artificial leather, and the like. v

The following examples illustrate dispersions employing other sulphonated oils: 4

Example 6 Per cent Casein 18.2 sulphonated olive oil 18.2 45 Water 54.5 Diethylene glycol 9.1 Example 7 Per cent 50 Casein 19.4 sulphonated coconut oil 19.4 Water 58.3 Triethanolamine 2.9

The above examples are merely illustrative and 55 similar dispersions may be obtained by using other sulphonated fixed oils. Sulphonated corn and rapeseed oils may be mentioned as other specific fixed oilswhich are particularly satisfactory, although the use of any sulphonated fixed oil is contemplated within the scope of the present invention.

Although the dispersions above described are of satisfactory clarity for most purposes, they may be improved somewhat in clarity by the addition of small amounts of triethanolamine, ethyl alcohol, and similar compounds.

As will be understood by those skilled in the art, plasticizers may be added to the dispersions in order to give films of increased flexibility. Among the more common plasticizers may be mentioned glycol, diethylene glycol, and trlethylene glycol. Likewise, pigments and dyes may be included in the dispersions to obtain colored Artificial leather may be produced by coating fabric, paper, or other woven or felted fibrous, flexible bases with these dispersions. The coating may be carried out by brushing or by the use of a doctor blade, or the film may be cast on the base.

These dispersions are suitable for coating textile and paper bases to form leather substitutes for use as upholstery, automobile coverings, bookbinding materials, window shades, and other products for which coated fabrics of this nature are commonly used.

As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

I claim:

1. A liquid composition which on drying forms a tough flexible film said composition comprising as a vehicle a neutral homogeneous water dispersion containing about 20% casein, 60% water,

and about 20% of a sulphonated fixed oil as the dispersing agent.

spears 2. A liquid composition which on drying forms a tough flexible film comprising as a vehiclea neutral dispersion of about 20% of casein, 75 to 10% of water, and 5 to 70% sulphonated' castor oil as the dispersing agent.

3. A liquid composition which on drying forms a tough flexible film comprising as a vehicle a neutral dispersion containing about 20% of casein in 65 to 40% water and 15-to 40% of sulphonated castor oil as the dispersing agent.

4. An artificial leather comprising. a flexible fibrous base sheet and superposed thereon a tough flexible surface film formed by coating over said sheet a liquid composition comprising as a vehicle a neutral homogeneous dispersion containing about 20% of casein, about water, and about 20% of a sulphonated fixed oil.

5. An artificial leather comprising a flexible fibrous base sheet and superposed thereon a tough flexible surface film formed by coating over said sheet a liquid composition comprising as a vehicle a neutral homogeneous dispersion consisting of about 20% of casein, '75 to 10% of water, and about 5 to 70% sulphonated castor oil.

6. An artificial leather comprising a flexible fibrous base sheet and superposed thereon a tough flexible surface film formed by coating over said sheet a liquid composition comprising 'a pigment and: as a vehicle therefor a neutral homogeneous dispersion consisting of about 20% of casein, to 40% of water, and about 15 to 40% of sulphonated castor oil.

'I. A liquid composition which on drying forms a tough flexible film comprising as a vehicle a neutral dispersion of about 20% of casein, '15 to 10% of a mixture of water and a glycol, and 5 to sulphonated fixed oil as the dispersing agent.

8. A liquid composition which on drying forms a tough flexible film comprising as a vehicle a neutral dispersion coating, about 20% of casein in 65 to 40% of a mixture of water and ethylene glycol, and 15 to 40% of sulphonated castor oil as the dispersing agent.

FRANK G. UHLER;