US2438366A - Drying of textile materials - Google Patents

Description

Patented Mar. 23, 1948 UNITED STATES PATENT OFFICE DRYING OF TEXTILE MATERIALS comp any No Drawing. Application February 19, 1946, Serial No. 648,816. In Great Britain April '1, 1943 Section 1, Public Law 690, August 8, 1946 Patent expires February 11, 1964 6 Claims. 1

This invention is a continuation in part of my copending application Ser. No. 553,481, filed September 9, 1944, now abandoned.

My present invention relates to the drying of textile materials such as fabrics, cords and yarns which have been treated or impregnated with aqueous preparations, particularly with aqueous dispersions of adhesive materials for bonding rubber to fabrics, cords or yarns.

Adhesive materials of the above types may comprise dispersions of plastics or plastic-forming reagents which may also contain some dispersed rubber.

Whencords, yarns or fabrics are treated or impregnated with an aqueous dispersion of the above type, whether it contains rubber or not. the resulting coating is tacky until a substantial amount of the water has been evaporated. It cannot, therefore, be handled or passed over rollers until a sufficient amount of the water has been evaporated as, for example, until the water content is reduced below 20%.

The evaporation of water from a tacky aqueous dispersion of the above type in an atmosphere of air is relatively slow and it therefore requires a tall or lengthy drying chamber in which the fabric, cord or yarn may be suspended for a sufiicient time .to permit the evaporation or, if the space is limited the drying must be correspondingly slow.

In my present invention I provide a method whereby suflicient water may be quickly evaporated and reduced to a point where the adhesive material is no longer tacky.

In my present invention the treated fabric is subjected to the action of superheated steam. The steam may be either at atmospheric or superatmospheric pressure or might in some cases be somewhat below atmospheric pressure. Preferably, however, the steam is at atmospheric pressure.

When the impregnated or treated fabric, yarn or cord is drawn through the superheated steam the water content of the aqueous material is immediately vaporized, that is, within a fraction of a second. Consequently, the cord, fabric or yarn may be passed through a steam chamber of limited length at a high speed.

As an illustrative example a two-fold 1100 denier viscous rayon cord treated with an aqueous preparation or dispersion of adhesive materials of about total solids is passed upwards at the rate of 120 yards per minute through a vertically disposed tube 1 foot long and an internal diameter of 2% inches and having an aperture of inch diameter at the bottom and an aperture of ,inch diameter at the top for the passage of the cord.

Steam at atmospheric pressure and at a temperature of C. is introduced into the tube at the same time by way of an inlet near the bottom of the tube.

The water content of the cord on entering the tube after treatment with the aqueous dispersion or preparation may be about 50%, and after emergence from the tube the water content is about 20%, in which condition it may be handled or passed over rollers without risk of sticking.

It will be understood that the above specific figures are given merely by way of example and that in any case a treatment of the impregnated.v or treated fabric'with superheated steam will reduce the moisturecontent of the fabric in'a short time to whatever degree is required to render the fabric non-tacky.

After the cord emerges from the top end of the tube .further drying may take place and after a passage of about 3 feet in the air the cord is,

wound on a bobbin.

The method is applicable to any cord or fabric treated with an aqueous preparation or dispersion of an adhesive for rubber to textiles. The dispersion may contain a quantity of rubber, such as natural or artificial latex, together with dispersed resins, or it may contain merely a dispersion of resin or resin-forming reagents.

Examples of aqueous preparations or dispersions are as. follows:

In the above examples the rubber Will include compounding solids.

nolic resin forming reagents and subjecting said The specific resins are given only by way of example as it will be understood that their function is a mechanical one, namely to adhere to the fabric or cord or yarn, and also to the rubber with which the fabric, or cord, or yarn is to be impregnated or coated and, therefore, to act as an adhesive.

For example instead of formaldehyde and resorcinol, phenol formaldehyde or phenolic resins might be employed either with or without rubber. The resin, or mixture of resins, should be one that will act as an eifective adhesive between the rubber and the textile material.

As a example of a textile cord or fabric a viscose rayon woven cord which comprises a plurality of parallel cords of viscose rayon held in parallel arrangement by comparatively weak weft threads at intervals larger than the distance between the cords may be treated with any of the above aqueous dispersions and is then dried by the passage vertically through steam introduced at 140 C. into a 3 inch slot having a height of 4 feet and 6 inches and a breadth somewhat greater than the width of the woven cord.

After emergence from the upper end of the slot the Woven cord is sufficiently dried to handle without sticking and may be batched in rolls for storage until required without risk of subsequent sticking. The woven cord may be further dried by passage around heated metal rollers without risk of sticking to the surface of the rollers.

Through the above invention, therefore, fabrics impregnated with an aqueous dispersion of an adhesive may be quickly dried sufiiciently for handling, thus enabling large quantities of the fabric to be prepared in apparatus of limited dimensions.

What I claim is? 1. The process of treating tire fabrics which comprises impregnating the fabric with an aqueous dispersion of rubber hydrocarbons and phenolic resin forming reagents and subjecting said fabric for a fraction of a second to dry steam at fabric to dry steam at substantially atmospheric pressure and at a temperature of about C. for a time sufficient to reduce the water content to 20% of the fabric.

3. The process of treating tire fabrics which comprises impregnating the fabric with an aqueous dispersion of rubber hydrocarbons and phenolic resin forming reagents and subjecting said fabric to dry steam at substantially atmospheric pressure to reduce the water content of said fabric to about 20%.

4. The process of treating tire fabrics which comprises impregnating'the fabric with an aqueous dispersion of a composition adhesive to rubber and to fabric and comprisingphenolic resin forming reagents and subjecting said fabric for a fraction of a second to dry steam at substantially atmospheric pressureat a temperature of about 140 C.

5. The process of treating-tire fabrics which comprises impregnating the fabric with an aqueous dispersion of a composition adhesive to rubber and to fabric and comprising phenolic resin forming reagents and subjecting said fabric to dry steam at substantially atmospheric pressure and at a temperature of about 140 C. for a time suflicient to reduce the water content to 20% of the fabric. l

6. The process of treating tirefabrics which comprises impregnating the fabric with an aqueous dispersion of a composition adhesive to rubber and to fabric and comprising'phenolic resin forming reagents and subjecting: said fabric to dry steam at substantially atmospheric pressure to reduce the water content of said fabric to 20%. 1 2 V JAMES ILLINGWORTH.

' REFERENCES CITED The following references are of record inithe file of this patent;

UNITED STATES PATENTS