SU1142559A1 - Method of producing paper - Google Patents

Abstract

A PAPER MANUFACTURING METHOD, including grinding a fiber suspension, introducing ethylenediaminetetraacetic acid disodium salt, treating the pulp with a sizing agent, coagulating agent, pouring out a paper web and drying it, in order to improve the physical and mechanical properties and the extent of paperwork. ethylenediaminetetraacetic acid is injected before casting the b5g cloth in an amount of 0.1-3.0% by weight of absolutely dry fiber at a pH of 4.5-7.5.

Description

1 The invention relates to pulp and paper industry and can be used for the production of various kinds of technical and printing paper types, mainly for glued paper. A known method of making paper and paperboard using a basic salt of the general formula M. (OH). Ha. at any stage before FI 1P n-fn molding, preferably after filling and sizing. The composition of salts: M - polyvalent metal; X-CS, nitro or acetate group, Cn-O, 100 (basicity) is 30-75%. Salt also contains polyvalent anion, selected from the anions of sulfuric phosphoric, polyphosphoric, silicic, chromic, carboxylic acids (citric, oxalic, fumaric, amber, etc.). The addition of 0.34, 0% salt improves sizing, retention, dehydration of QJ paper web. However, this method of making paper does not achieve high physical and mechanical properties of paper (breaking weight, breaking length, fracture, punching, etc.). The closest to the invention is a method of making paper, including grinding fiber suspension, adding ethylenediaminetetraacetic acid disodium salt. , processing of fibrous masses with a sizing agent, coagulum on the flow of a paper web and drying. B. In this way, the introduction of disodium ethylenediaminetetraacetic acid into the fibrous suspension is carried out in the process of grinding the fibrous suspension in an amount of 0.02% by weight of absolutely dry fiber in the presence of alkali (40-80%), phosphates or polyphosphates (20-60%) and May 1020.4. sodium gluconate or citrate, i.e. at pH not lower than 8.0. The whole compound in the complex improves the mol of cellulose, i.e. reduces the time of grinding, saves fibrillation of fibers, which improves the strength properties of paper 2. However, the introduction of the disodium salt of ethylene diamine tetraacetic acid in the specified amounts in the process of pulping in the specified amounts does not increase the mechanical strength of the paper. In addition, the grinding process. goes in a strongly alkaline environment, requires its neutralization at the sizing stage. The purpose of the invention is the development of physico-mechanical indicators of the degree of sizing paper. The goal is achieved by tTo according to the method of making paper, including grinding a fiber suspension, introducing ethylenediaminetetraacetic acid disodium salt, treating the fibrous mass with a sizing agent, coagulating material, emptying the paper web and drying it, ethylenediaminetetrastrostroist disprocer, and the subject and the artist and the artist and the tracer. 0.1-3.0% by weight of absolutely dry fiber at pH 4.5-7.5. Introduction to pulp before discharging the paper web of disodium eulenediaminetetraacetic acid in an amount of 0.13, 0% leads to an improvement in the physical and mechanical properties of the paper, such as rupture length, fracture, resistance to bursting, as well as increasing the sizing of paper. The established expenses of etipediamintetrauksuyu disodium salt are necessary because its use in an amount less than the minimum limit is not enough to increase the physical and mechanical properties of paper, and an excessive increase in the consumption of this salt with a relatively small increase in this effect leads to an increase in the cost of paper. The pH of the paper pulp found is also optimal. As the pulp being treated, the pulp can be used, the fiber suspension only, as well as the sizing and filling substances can be used. As fibrous semi-finished products, the following products can be used: cult coniferous and deciduous bleached and unbleached cellulose, sulfite henbane cellulose, wood henbane, thermomechanical. mass and mixtures thereof. Can be used as glueing rosin and synthetic adhesives. As a filler, kaolin, chalk, titanium dioxide, silica based fillers and others can be used. Aluminum sulphate, aluminum-potassium or ammonium alum, aluminum chloride and others can be used as a coagulant. If necessary, flocculant can be used. The treatment of the pulp in the proposed papermaking process is carried out as follows. Disodium ethylenediamine of acetic acid is pre-dissolved at room temperature to a concentration of 1-5 g / l, then introduced into the pulp before casting the paper web after filling with kitsi, sizing agents and aluminum sulphide at pH 4.5-7, preferably 5, 0-6.5. The filling, sizing of the fiber suspension and the introduction of the coagulant are carried out in the usual manner. The paper can be calendered if necessary, depending on its purpose. Example 1. For the manufacture of paper, paper pulp is prepared, including 70% sulphate larch bleached and 30% sulphate pulp bleached pulp, ground together to 35 ° B1P. Rosin glue, kaolin, aluminum sulphate to pH 5.5 and ethylenediaminetetraacetic acid disodium salt are added to the ground fibrous suspension in the amount of absolutely dry fiber. The paper (weight 80 g / m) is poured from the prepared paper mash and dried and calendered. The test results of the paper are shown in the table. Example 2 (for comparison). Analogously to Example 1, paper was made without the introduction of ethylenediaminetetraacetic acid disodium salt. The physicomechanical parameters of the paper obtained are given in the table. Example 3. For the manufacture of paper, a paper pulp was prepared as in Example 1 and the pH was adjusted to 7.5 with an alkali solution. Ethylenediaminetetraacetic acid disodium salt is added in an amount of 0.1% by weight of absolutely dry fiber. Next, the paper is prepared according to example 1. The results of the paper tests are shown in the table. Example 4 (for comparison). Analogously to Example 3, paper was prepared with the introduction of 0.06% disodium salt of ethylenediaminetetraacetic acid based on the weight of absolutely dry fiber. The test results of the paper are shown in the table. Example 5. For the manufacture of paper according to the proposed method, a fibrous suspension is prepared, comprising 70% sulphite softwood pulp and 30% sulphate hardwood bleached pulp, melted together to 35 SR. Rosin glue, aluminum sulphate to pH 4.5 and ethylenediaminetetraacetic acid disodium are added to the milled fiber suspension in an amount of 3% by weight of absolutely dry fiber. Before paper is poured in, an amount of 0.01% by weight of absolutely dry fiber is introduced. After ejection and drying, the physicomechanical properties of the paper are given, which are listed in the table. Example 6 (for comparison). Analogously to Example 5, paper was prepared with the administration of 4% ethylenediaminetetraacetic acid disodium salt. The test results are shown in the table. PRI me R 7 (prototype). For the manufacture of paper according to the method, a fibrous suspension is prepared, including bleached pulps: 70% softwood sulphite and 30% hardwood sulphite. The pulp suspension developed after the pulper was introduced (1% by weight of absolutely dry fiber), wt.h. Alkali (NaOH) 60 Sodium Phosphate (.) 40

15

Sodium citrate ethylene diamine tetraacetate

and then grind in a conical mill to. Thereafter, rosin glue and aluminum sulphate are added to the ground mass to a pH of 5 and 80 g / m2 paper is cast.

I

The results of testing the resulting paper are presented in the table.

As can be seen from the results presented in the table, the use of

The proposed method of making paper with the same composition of paper pulp PG compared with the prototype allows to significantly increase the physical and mechanical properties of paper.

Comparison of the obtained data shows that the proposed method of making paper makes it possible to increase its breaking length up to 22%, resistance to punching by 2 times, sizing by 2 times. Such an indicator of paper as a kink increases 4-5 times especially sharply.

Claims (1)

METHOD FOR PAPER MANUFACTURE, including grinding the fiber suspension, introducing disodium salt of ethylene diamine tetraacetic acid, treating the pulp with a sizing agent, a coagulant, casting the paper web and drying it, characterized in that, in order to increase the physicomechanical properties and the degree of sizing, the paper is double-glued, acids · are introduced before the casting of the paper web in an amount of 0.1-3.0% by weight of absolutely dry fiber at a pH of 4.5-7.5. • 3 Π42559 1 1142559