FR2515710A1 - METHOD FOR IMPREGNATING TEXTILE OR EQUIVALENT STRIPS OR BANDS BY MEANS OF IMPREGNATION AGENT MADE IN THE FORM OF FOAM - Google Patents

Abstract

PROCESS FOR IMPREGNATION OF TEXTILE OR EQUIVALENT STRIPS OR SHEETS BY MEANS OF AN IMPREGNATION AGENT PUT IN THE FORM OF FOAM. TO IMPREGNATE STRIPES OF TEXTILES OR EQUIVALENTS WITH THE USE OF A LOW QUANTITY OF WATER (TO REDUCE ENERGY CONSUMPTION FOR DRYING), TREATMENT AGENTS (PRIMERS, CHEMICALS, COLORS, ETC.) ARE DEPOSITED AT L 'STATE CONVERTED INTO FOAM, AND IN THE FORM OF A FILM OR A STRIP OF FOAM, THE STRIP HAS BEEN PREVIOUSLY HEATED TO PROMOTE COLLAPSE OF THE FOAM AND ITS PENETRATION INTO THE MATERIAL. THE BAND HAS PREFERREDLY BEEN IMPREGNATED WITH WATER VAPOR, EITHER BY HEATING ITS RESIDUAL HUMIDITY, OR BY VAPORIZATION, SO THAT, PLACED IN CONTACT WITH THE COLD FOAM, THE VAPOR CONDENSES AND CREATES A VACUUM WHICH PENETRATES 'CORE IMPREGNATION AGENT IN THE FIBERS OF THE BAND.

Description

The invention relates to a method for impregnating strips of

  movement, such as textile webs, textile-like webs, and it relates in particular to the application to the impregnating agent on webs of

  ter in the state turned into foam.

  To keep energy consumption at a low enough level in the wet-processing of strip materials, consumption which results from the drying of the strips of material to be treated, which is generally necessary after

  wet treatment, we have recently begun to apply

  impregnating agents such as primers,

  chemicals, dyes or the like, with a minimum

  quantity of water, in the form of diacritic foams

impregnation.

  So that a collapse of the foams occurs on the strips of material to be treated and, therefore,

  a quick transfer of the liquid to these materials, we use

  Until now, mosses have remained stable for only a relatively short time.

  frequently faced great difficulties in

  the irregularity of the collapse of these foams on the strips of materials to be treated with, as a consequence, formation of spots and marks. In the known processes, the liquid ceded by the foams

  Penetrates poorly into the bands to be treated.

  The present invention aims to avoid these disadvantages and, in particular, to solve the problem of allowing the use of stable foams, which can be

  maltreated with security, to achieve a ripe collapse

  foams on the strips of material to be treated.

  and in particular, to guarantee the perfect penetration of the liquid ceded by the foams into the material bands

treat.

  To solve this problem, it is proposed according to the invention, in a process of the kind mentioned, to heat the strips of materials to be treated before the application of the impregnating agents and, only then, to apply the impregnating agents such as primers, chemicals or dyes on heated webs, in the foamed state, in the form of films or webs

of foam.

  In a preferred embodiment of the invention, the application of the films or strips of foam on the strips

  of heated materials should only be carried out

  When this is done, the foaming can be carried out in foaming devices known in the form of films of about 0.5 to 5 mm thick, the films or strips of foam being

  transferred first, for example, to a roller

  who then carries them to the strips of

  In this way, the dosage and formation of the foam film are separated from the collapse of the foam on the strip of material to be treated and can

  therefore be mastered with s-security.

  The heating of the strips of material to be treated must

  advantageously be carried out to a degree such that the moisture

  contained in the band or the residual moisture gives rise to a release of water vapor which is maintained until the moment of application of the impregnating agent foam The vapor formed in the material band

  heating then condenses with the transfer of its heat.

  their foam, so that it forms a vacuum under the effect of the foam or the liquid ceded by the foam

  is sucked inside the material band and penetrates

to be deeply in this one.

  It has been found advantageous, in the case of strips of material which are wet in the initial state, to dry these strips to the degree most favorable to the absorption of the impregnating agent foam, this degree being 'about

  at 40% in the case of cellulosic fibers, at least.

  the last part of the drying treatment to be

  performed in a medium with a high vapor content.

  In the case of dry material bands in the initial state, heating should preferably be carried out by means of

  water vapor and in a pressurized atmosphere.

  In order to ensure core heating of the fabric or other complex of yarns or fibers, the heating of the strips of materials to be treated can advantageously be effected by blowing or aspiration of water vapor through the strips. We can still favor the collapse

  foam on the strips of material to be treated by

  these bands, after the application of the improper

  to another heat treatment, for example,

in a spray chamber.

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Claims (6)

R E V E N D I C A T IO N S   Process for impregnating moving webs or sheets of material such as textile webs, textile-like webs or the like, characterized in that the webs of materials to be treated are heated prior to the application of the impregnating agents and impregnating agents, such as finishes, chemicals or dyes, are then applied to the strips of material to be processed in foam form, in the form of films or strips of foam.   Process according to Claim 1, characterized in that the application of the foam films or strips occurs on the pre-heated strips of material to be treated, after complete formation of the films or webs, at a distance-downstream from the training area.   Process according to one of Claims 1 and 2,   characterized in that the heating of the strips of material to be treated is carried out to a degree such that it occurs,   from the moisture contained in the   to be treated, a release of water vapor, which is maintained until the moment of application of the foam impregnating agent.   Process according to one of Claims 1 to 3,   characterized in that, in the case where the strips of materials to be treated are wet in the initial state, these bands are dried to a degree favorable to the absorption of the impregnating agent foam, at least the last part drying-treatment being performed in a   medium with a high proportion of steam.   Process according to one of Claims 1 to 3,   characterized in that, in the case where the strips of materials to be treated are dry in the initial state, the heating of these strips of materials is carried out by means of   of water vapor in a pressurized atmosphere.   Process according to one of Claims 1 to 5,   characterized in that the heating of the material webs   to be treated is effected by blowing or aspiration of water vapor through these strips of material * I 2515710 1 5   Process according to one of Claims 1 to 5,   characterized in that after the application of the impregnating agent foam, the strips of materials to be treated are subjected to another heat treatment, preferably in a vaporization chamber.