SU956685A1 - Fibrous mass for making paper - Google Patents

Description

This invention relates to the pulp and paper industry, in particular to the manufacture of printing papers. Known pulp for making paper, such as printing, containing modified bleached sulfite softwood pulp and unmodified bleached pulp. (Sulfate hardwood pulp) 1. However, paper made from this mass has insufficient ash content and wet strength. The purpose of the invention is. improved filler filler and paper wetness. This goal is achieved by the fact that the pulp for papermakers, mainly printed ones, containing modified bleached sulfite softwood pulp and unmodified bleached pulp, contains sulfite softwood pulp as the unmodified bleached pulp in the following ratio of components, wt.%: Modified bleaching sulfate softwood pulp in the following ratio of components, wt% - Cellulose 10-99 Unmodified henbane sulfite coniferous cellulose. 1-90 Modified cellulose is obtained by treating sulphite pulp with monosulphite liquor. Various methods are known for producing modified bleached sulfite cellulose. As a result of the interaction of cellulose with monosulfite liquor, hemicellulose dissolved in it, which are mainly glucuronoxylan, is absorbed into cellulose fibers. The amount of sorbed glucuronoxylan in cellulose can be determined by the increase in pentosan content, which, depending on the processing conditions, is from 0.1 to 6%. From the proposed pulp, technical and printing papers can be produced. Depending on the type of paper, the required amount of sizing agent, precipitator, filler, substances that increase filler retention are added to the mass. PRI me R. A modified bleached sulphite coniferous cellulose is taken, having the following extractors: whiteness - 87.1%, total content of pentosans - 7.5%, of which sorbed - 2.6% and ordinary, bleached sulphite coniferous cellulose, having a white consumption - 87.2%, the content of pentosan - 4.9%. When the modified and ordinary bleached celluloses are grinded together, their compositions are prepared in various ratios (tabl) and ground to a grind grade of 32-33ShR. With separate grinding of these celluloses to 32-33ShR, the composition by fiber in predetermined ratios (Table 1) is prepared from ground masses before reflux. The grinding time of the modified bleached sulfite pulp to 33 ° ShR 12 min. The duration of the grinding of conventional bleached sulphite pulp and its mixtures with modified cellulose is given in table 1.

. Under laboratory conditions, a Tsidp RapidKeten type CBTF apparatus was used to make paper from pulp containing variously bleached (Table 1) modified bleached sulfite pulp and ordinary bleached sulfite pulp. Consumption of rosin-paraffin glue - 3% by weight of paper, alumina - 6%, kaolin - 40%, polyacrylamide - 0.4%. The resulting paper samples were tested according to standard methods. The test results are shown in the table. .

Table 2 presents comparative data on the quality of the proposed fibrous mass and the known.

Thus, the proposed fibrous mass has higher paper-forming properties compared to the weight of bleached sulfite pulp and the weight of modified cellulose and bleached sulfate hardwood pulp.

table 2

Medium rupture length in wet

n / a kaolin consumption 24% of the mass k / a kaolin consumption 40% of the mass Formula of the invention Fibrous mass for the manufacture of paper, mainly printed, containing modified bleached sulfite softwood pulp and unmodified bleached softwood pulp, characterized by the fact that to increase the retention of filler and the strength of the paper in the wet state, the weight as unmodified bleached pulp contains sulphite

softwood pulp next

the ratio of components, wt.%: Modified henbane sulfite coniferous cellulose 10-99 Unmodified henben coniferous cellulose 1-90 Sources of information,

taken into account in examination 1, USSR Copyright Certificate

According to application number 2694249/12,

cl. D 21 H 3/00, 20,11.78.

Claims (1)

SUMMARY OF THE INVENTION A pulp for the manufacture of paper, mainly printed, containing modified bleached sulfite softwood pulp and '(modified bleached softwood pulp, characterized in that, in order to increase the retention of the filler and the strength of the paper in the wet state, the mass as unmodified bleached pulp contains sulfite softwood pulp in the following jc ratio of components, wt.%: Modified bleached sulfite softwood pulp 10-99 ^ modified bleached softwood naya cellulose 1-90