US1852065A - Impregnating webs, cloths and fabrics - Google Patents

Description

' P 1932- E. SCHNAB'EL ET AL 1,852,065

I IMPREGNATING WEBS, CLQTHS, AND FABRICS Filed A ril 11. 1930 Patented Apr. 5, 1932 UNITED STATES.

PATENT OFFICE. f

EHIL SCHNAIBEL, or DEBSAU IN ANHAL'IE, .AND FRIEDRICH A. w minim, or MANN- nam, GERMANY, assmnoas TO I. a. raannnmpns mm AKnENeEsELLscnu'r, or rRANxronr-oN-rnE-mim', GERMANY IMPREGNATING wEBs, cLo'rns A ND FABRICS Application filed 11 1111 11, 1930, Serial No. 443,439,]:11111 in Germany March -1, 1929.

Our present invention relates to a process 10 special table andlapplying the impregnating solution thereon from above by means of an atomizer or a, pouring device. This process presents the disadvantage of allowing-only ,part of the air bubbles contained inthe web to escape upwardly in consequence of the high viscosity of the impregnating solution, so that the impregnated web, when the imiregnating liquor has solidified, contains air ubbles.

According to our present invention, 1mpregnated webs free from air bubbles, are obtainable in a simple manner by removing the air contained in the web of fibrous mamediately before the impregnating liquor'is applied on to the web. This removal of the air and: the impregnation of the web-can also be carried out in one working operation; This can be doneb applying theimpreg- 'nating liquor from elow and thus utilizing ..the solvent vapors evolved by the liquor itself. The impregnating liquor penetrating ,into the web from below' is preceded by a layer of solvent vapors driving out. the air, enclosed in the interstices between the single fibers," in an upward direction and thus ensures a complete impregnation of the web Also if the. vapor tension of the impregnating liquor be only relatively small, the air is practically completely driven out from the web because, by the action of the impregnating liquor which rises from below, it is forced upwardly where it may freely escape.

terial by means of'solvent vapors before the without any air bubbles being left therein.

I Furthermore, the new impregnating procoss may be completed, if, desired, by applying, according to known methods,'a jfurther impregnating liquor on the upper surface of the web beforethe impregnating liquor.- applied totho lower surface has been dried. For this PHIPO'SQ either'the same or another impregnating liquormay be used.

The process can be conducted with the aid of all devices which allow the impregnating liquor to be carried to the lower surface'of the web of fibrous material. however, a known drumor a band pouring Preferably,

machine is used, in which the impregnating liquor is poured, by means of a film-casting tunnel havinga slitiof corresponding breadth on :r'uniformly moving solid support which is p'rovidmlwith guide-devices. for the web. These guide-devices,v for instance, suitable rollers or the like, lead; the web to the exitslit of the film-casting funnel or. to a placeimmediately behind it, so that the web to be impregnated lies closely on the layer-of impregnating liquor flowing out ofthefunnel. The web .can be guided to the film-casting .slit. for instance, in such a manner that'itis caused to slide downwardly at the front wall of the funnel, while lying closely and uniformly on the inner side thereof and then. to reach the conveyer bandor the drum car-.

rying the impregnating liquor, se l {that it lies closely on the outflowing liquor. Since,

when simply guiding the web through the funnel, the danger exists that it is prematurely soaked with the liquor and thea-ir bubbles driven out thereof enter the. latter, it is recommendable to provide for this process a particular funnel having a double front'wall through which the web passes without touching the impregnating liquor before the exit of 'the'liquor supplying device.

which preferably maybe used. I

The web I to. be impregnated is reeled ofi ed, the web is guided over rolls to the slit- Fig. l of the drawing diagrammatically illustrates our new process and the apparatus of a film-casting'funn'el C arranged above the conveyer band G of a film-casting machine.

Fig. 2 shows an embodiment of the funnel in section. The impregnating liquor- F is filled into the film-casting funnel C from, which it flows to the conveyer band G through the slit H. The funnel Chas a double front wall formed by the plates E and D through which the web I is guided to the slit H of the funnel C, which may be adjusted by means of a hand wheel K. The plates D and E are parallel to each other and distanced, so that the web to be impregnated may be guided through the formed interstice.

The process of impregnating may also be performed with the use of a film casting funnel not provided with a double front wall, by guiding, for instance, the web by means of rollers closely in front of the slit of the funnel.

After having passed the outlet H of the funnel. C, the conveyer band G is covered with a thin layer of the impregnating liquor which on the forward movement continuously enters the web I lying closely thereon.

The webs to be impregnated may be woven fications and equivalents as fall within the scope of the appended claim.

What we claim is A device for impregnating webs, cloths and fabrics comprising a support for the material to be impregnated and a funnel for casting a uniform layer of the impregnating solution on the said support, a double front wall on said funnel for guiding the material to be impregnated and for imposing it on the layerof impregnating solution formedimmediately at the exit of the said funnel.

In testimony whereof, we aflix our signatures.

EMIL SCHNABEL. FRIEDRICH A. W. KI'JHNE.

of animal or vegetable, natural or artificial fibers as, for instance, cotton, wool, silk, jute, ramie, nettle, artificial silk and so on.

As an impregnating compound, we may use cellulose derivatives, natural or artificial resins, guttapercha, balata, caoutchouc, and so on, or mixtures of these products, if necessary, with addition of oils, softening or filling agents, pigments or dyes. In preparing the impregnating liquids, we may use the organic solvents, known in the art, preferably acetone, benzene or halogenated hydrocarbons.

The thickness of the layers to be applied to the webs may vary between 1 to 3000 11.,P18ferably, layers of about 50 a and more are produced. Obviously, the thickness depends upon the concentration of the impregnating liquid and on the opening of the film-casting funnel. The temperature of the impregnating liquid may be varied within wide limits; the same holds true with regard to the suport on which the layer of impregnating iquid is cast. Too high temperatures, however, are preferably avoided. By a suitable selection of the solvent, temperature, concentration and viscosity of' the impregnating liquor, any desired impregnation, free from air bubbles, may be performed. Thelayer applied to the web may be dried by warming the support carrying it or by blowing warm air over the impregnated fabric. These specific details and the recovery of the solvents likewise are well known from the industry dealing with the manufacture of celluloid films or oilcloth.

Numerous other embodiments of our in-' yentlon are possible and we contemplate as included within our lnventlon all such modi

Images