SU802433A1 - Method of manufacturing electric insulation paper - Google Patents

Description

one

The invention relates to the manufacture of electrically insulating booms with improved dielectric properties and can be used in enterprises for such types of paper.

A known method for the manufacture of electrically insulating paper, including the preparation of paper pulp, casting a web, pressing, processing with a chemical reagent, drying and calendering. We use weak acids as a chemical reagent, for example, hydroquinone. This method is suitable for the manufacture of electrically insulating J impregnated with petroleum oils and 2j.

However, this method does not improve the dielectric properties of electrically insulating paper intended for impregnation with other common types of impregnating masstriodiphenyl, castor oil, etc.

The purpose of the invention is to reduce and stabilize the tangent of the dielectric angle, 1.; lt-: c1; their losses, - as well as possible ;; o: - ..: -, p; - o-zedsip processing process ;; gh C;: -; m og,: - eito; at any stage:. ;; XT-i eLiv; .-pectroizol tshonioy bu | T ,,; -, G: k.ch. chemical

G: - --.- ,, -. iV (.HvnoT boric acid

. :.,:; Lch1-about rt weights absolute .-, -: .1Гег, In this case use: -; -; ,; O, 1–2G; 5: aqueous solution of GHG acid.

The process technology is as follows. Turn off the paper vioccy. the fabric is molded, pressed and processed with boric acid. Measurement 1 with boric acid is performed by wetting condenser paper with low dielectric losses of the ICOH grade according to TU 81-04-243-73 before calender-. to a bulk density of 1.20 r / CNT. The treatment is carried out with a 4.5% boric acid solution. The test results are shown in Table. one.

Table

Thickness, µm Bulk mass, g / cm Breakdown voltage

Number of conductive inclusions per 1 m

The tangent of the dielectric loss angle in dry form, temperature, ° C,

The tangent of dielectric loss angle with propich trichlorodiphenyl at

Example 2. 10 g of electroneous cellulose are placed in a cylindrical container of a laboratory mixer and poured 1000 ml of a 0.1% aqueous solution of boric acid. Then, within half an hour, a breakdown is made in cellulose, and after this, grinding the obtained suspension in a laboratory mill for 12 hours to 90 ° ShR. Next, the resulting paper pulp is diluted with 1000 ml of water and laboratory samples of papers with a bulk weight of 7 g / cm

Example 3. 10 g of air-dry cellulose is placed in a laboratory agitator container and treated with 100 M716% boric acid solution, then 900 ml of deionized water are added, broken down for half an hour, then 12 hours, grinding at 10, 3 1.17 470

70

0.14 0.13 0.14 0.16 0.22

0.43

0.36

In parallel, make paper from paper pulp that does not contain boric acid.

In tab. 2 shows the tangent values of the dielectric loss angle of the manufactured papers.

The determination of the -tgt papers described in all the examples given was made according to GOST 16746-71 at a voltage of 5 V / µm and a frequency of 50 Hz. The content of boric acid in the paper is indicated in parentheses.

Table 2

rator mill, add 1000 ml of deionized water and make laboratory samples of papers with a mass mass of 0.7 g / cm.

Table 3 shows the tangent values of the dielectric loss angle of paper. Sample Normal paper Paper with boric acid (0.6%) Example4. 10 g of air-dry cellulose are placed in a container of a laboratory mixer and treated with 100 ml of a 28% boric acid solution. Then 900 ml of deionized water are added, cellulose is broken down during the preparation in a lab blender, and then Sample Plain paper Boric acid paper (2.6%) Example 5. Same as in Example 4 , ic using water, Sample Plain paper Paper with boric acid (2.6%) EXAMPLE 6: Under industrial conditions, I disintegrate cellulose as a paper pulp with a concentration of 1.8% in an amount of 150 g and is diluted with 850 ml 0.1% boron solution Sample Plain paper Paper with boric acid. (0.2%) Table 3 of the paper at a temperature of 11 60 I 100 120 0.085 0.09 0.12 0.07 0.07 0.07 for 10 hours grinding in a laboratory ball mill is added with 1000 ml of deionized water and make laboratory samples of paper volume weight of 0.7 g / cm. In tab. 4 shows the tangent values of the dielectric loss angle of the paper. Table4 1 cP paper at a temperature, ° С, -11 60 100 120 0.085 0.09 0.12. 0.040.04 0.04 applied in the preparation of paper in examples 3 and 4 (see Table 5 /. Table-tgfo paper at a temperature, C. T -, -: 60100 120 0.090.17 0.25 0.040.04 0 , 05 acids on deionized water. The results of the test paper samples are presented in Table 6. The volumetric mass of paper is 0.7 g / cm. Table Tabg tgcf paper at ° C tF 60 100 1 120 0.035 0.09 0.012 „n 0 , 08 0.08 0.09

Example. The pulp ground under production conditions in the form of paper pulp. With a concentration of 2.0% in an amount of g is treated with 100 MP of a 28% aqueous solution of boric acid, and then ordinary water with an electrical conductivity of 250 is added.

Example. A sample of the BG paper of the wet state is treated with a uniform spray on it before drying. the whole sheet with a 0.1% boric acid solution in an amount of 10 ml per casting, weighing 8 g in the wet state (1.1 g ab- containing 0.5-0.6 meq / l sodium salts, stirred and make laboratory samples of papers with a mass weight of 0.7 g / cm3.

In tab. 7 shows the results of the test papers.

Table salt dry fiber. After spraying, remove the excess moisture from the papermaking and dry. Bulk paper weight 0.7 g / cm.

In tab. 8 shows the results of testing paper samples.

Table8

Claims (3)

0.080 0.080 0.10 The formula of the invention. and i 1. A method of manufacturing an insulating paper, including the preparation of paper pulp, sheet casting, pressing, processing with a chemical reagent, drying and calendering, characterized in that, in order to reduce and stabilize the dielectric loss tangent, as well as the possibility of carrying out a chemical reagent processing for any stages of manufacturing insulating paper, boric acid is used as a chemical reagent. 2. The method of pop. 1, distinguishing with the fact that the amount of boric acid is 0.1 - 6% by weight of absolutely dry paper. 3. The method according to PP. 1 and 2, □ t l and the fact that they use a 0.1 - 28% aqueous solution of boric acid.