SU857335A1 - Method of production of multilayer web from fibrous materials - Google Patents

Description

(54) METHOD OF MANUFACTURE OF MULTILAYERED STRIP FROM FIBROUS MATERIALS

one

The invention relates to the production of multi-layer webs of fibrous materials and can be used in the pulp and paper industry.

A wet method is known in which two elementary layers are cast from a liquid mass, they are partially dewatered, and a third layer is cast between the two layers obtained with further dehydration of the multilayer web. This method makes it possible to obtain a multi-layer web with the same surface structure on both sides (1 |.

The disadvantage of it is a significant consumption of fresh water.

A known method for producing a fibrous web by dry forming it is that the fibrous web is molded with air from dry fiber and then glued with synthetic latex. This method produces a fibrous web without the use of water 2.

The disadvantages of this method are that the paper obtained is heterogeneous in structure and has different properties of each of the surfaces.

There is also known a method according to which two elementary layers of a fibrous web are molded from dry fiber, a binder is fed into the gap between the convergent elementary layers, then both elementary layers are joined using 5 binder. This method eliminates the use of water, which is an advantage over the wet method of paper production (3J.

The main disadvantage of the known method is that the resulting fibrous web, due to the absence of interfibre hydrogen bonds, does not have the same solidity and tightness of the paper surface.

15 The purpose of the invention is to improve the quality of the resulting web.

To achieve this goal, according to the method of producing a multi-layered web of fibrous materials by dry forming the outermost layers, combining them

Claims (3)

I, through binder and drying, use a pulp of 0.8-1.0% as a binder, and the combined layers are dehydrated. The technology of the method is as follows. The crushed dry fiber in an air stream serves on two inclined grids on which two elementary layers are formed using a vacuum. At the time of the meeting of two elementary fibrous layers formed by the dry method, paper pulp with a concentration of 0.8-1.0% is fed into the wedge gap between them. The liquid paper pulp, filtering through each elementary layer, fills all the voids between the fibers and, by virtue of its specific properties, creates interfiber hydrogen bonds, ensuring the uniformity of the structure of the fibrous layers. The combined multi-layered fibrous web is continued to be dewatered with the help of dewatering elements of the grid part, after which it is passed by means of a perforated shaft into the press section, where it is pressed And then dried in the usual way. The production method of a multi-layered web of fibrous materials allows to obtain a paper web with a uniform structure and a closed surface, and the use of the dry method of forming elementary layers significantly reduces the consumption of fresh water and simplifies the treatment of industrial Wastewater. The invention of the method for the production of a myoglasteous cloth from fibrous materials by dry forming the outer layers, joining them by means of a binder and drying, characterized in that, in order to improve the quality of the web, a pulp of 0.8-1 0%, and the combined layers are subjected to dehydration. Sources of information taken into account in the examination 1. US patent number 3867252, cl. 162-268, 1976. 2. The UK patent number 1276002, cl. D 1 R, 1974. 3. The patent of France 2252439, cl. D 21 B, 1976 (prototype).