JPS63270887A - Deinking agent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a deinking agent for recycling used paper for disintegrating and deinking printed waste paper.

[Conventional technology]

In order to recycle waste paper and obtain recycled pulp, it is necessary to deink the printed waste paper. As for the deinking method of used printed paper, ■
Waste paper is digested with alkaline chemicals and deinking agents (surfactants) in an earth pot under high temperature and pressure, and then the digested product is passed through wires of a decker, extractor, inclined screen, etc. to remove ink particles. Cleaning method, ■ An improved method is to treat waste paper with an alkaline agent and a deinking agent in a pulper, and then perform the same operation as the cleaning method described above to remove ink particles. After treatment with chemicals and deinking agents, air is blown into the treatment liquid to cause the ink to adhere to bubbles to remove ink, such as the flotation method.

Conventional deinking agents used in both methods include alkylphenol ethylene oxide adducts, higher alcohol ethylene oxide adducts, higher fatty acid ethylene oxide adducts, and fatty acid amide ethylene oxide adducts.

[Problem that the invention seeks to solve]

However, such conventional deinking agents have insufficient releasability of printing ink, especially ink releasability from offset printing paper, resulting in a large amount of residual ink.

Furthermore, because the emulsifying power of the ink and the ink-collecting power of the foam are weak, high-quality deinked pulp cannot be obtained by either the washing method or the flotation method.

Furthermore, since the foam-breaking property is poor, there are problems such as foaming failure after the deinking process.

This invention is intended to solve the above problems.

The purpose of this invention is to provide a deinking agent that has good releasability of printing ink, strong ink emulsifying power and ink collecting power of bubbles, and good foam-breaking properties, so that no foaming failure occurs in the process after deinking. shall be.

[Means for Solving the Problems] The present invention is a deinking agent containing an alkylene oxide adduct of an alkylphenol resin as an active ingredient.

The alkylene oxide adduct of the alkylphenol resin used in the present invention is a polynuclear alkylene oxide adduct of alkylphenol, whereas the conventional one is an ethylene oxide adduct of a mononuclear alkylphenol, and has the following general formula [1 ) is preferred.

(However, R is an alkyl group having 4 to 18 carbon atoms, xO is C,
H40 or C,xH2O and C,H,O or C4H
mixed polyoxyalkylene group with 11O, m is 5 to 20
0. n represents 4 to 50) In general formula (1), CH, is generally bonded to the orto position and R is bonded to the para position, but Good too.

Such alkylene oxide adducts of alkylphenol resins can be obtained by, for example, mixing and heating alkylphenols and formaldehyde in the presence of an acid catalyst (e.g. sulfuric acid) to synthesize an alkylphenol resin consisting of 4 to 50 nuclei, and then synthesizing this alkylphenol resin. After placing in a pressure container and heating and dehydrating with KOH under reduced pressure, ethylene oxide, propylene oxide, butylene oxide, etc.
Around 0℃.

It is produced by adding at 1 to 3 atm. At this time, in the case of block bodies, ethylene oxide, propylene oxide,
Butylene oxide etc. are reacted sequentially.

In the case of random bodies, a mixture of these is reacted.

The deinking agent of the present invention may contain only one kind of alkylene oxide adduct of the alkylphenol resin, but it may contain two or more kinds depending on the differences in R, X, m, n, etc. They may also contain other surfactants or other additives.

When the deinking agent of the present invention is added to the system when waste paper is disintegrated and recycled, printing ink can be peeled off from the fibers. This deinking agent can be applied to any of the washing method, flotation method, and other methods. The place where the deinking agent is added differs depending on the disintegration method, but as with conventional methods, it is added to the pulper, reaction tower, etc. before disintegration in the deinking process, or before the floatator. Although the amount added varies depending on each system, it is generally 0.001 to 1% by weight, preferably 0.1 to 0.5% by weight, based on the waste paper, as an alkylene oxide adduct of alkylphenol resin.

When waste paper is disintegrated and recycled, when the deinking agent of the present invention is added, the ink is exfoliated and dispersed in the pulp, and is removed by a washing method or a flotation method. In this case, 1 the deinking agent of the present invention is a mononuclear substance, whereas the conventional one is a mononuclear substance,
Since it is a polynuclear substance, it has a high affinity with ink, and ink removal and emulsification are performed well, and the ink collecting power due to the bubbles is also large.

Therefore, in both the cleaning method and flotation method, the removal rate of printing ink is higher than that of conventional methods.
This reduces the number of residual ink particles, improves whiteness, and improves the b value in the Lab color difference formula. Further, since the deinking agent of the present invention has excellent foam-breaking properties, foaming problems do not occur, and processes subsequent to the deinking process such as the paper making process can be carried out under normal conditions.

〔Effect of the invention〕

According to the present invention, since the alkylene oxide adduct of the alkylphenol resin is used, the releasability of the printing ink is better than that of the conventional method, and the amount of residual ink is reduced. Furthermore, since the emulsifying power of the ink and the ink collecting power of the bubbles are strong, a high quality deinking pipe with high whiteness and b value can be obtained in both the washing method and the flotation method. Furthermore, since it has excellent foam-breaking properties, there is no problem with foaming in the steps after the deinking step.

〔Example〕

Next, examples of the present invention will be described. In each example.

% is by weight.

Example 1 Deinking treatment was performed using the deinking agent shown in Table 1.

The deinking method is as follows.

(1) Disintegration of waste paper Cut 70 g of used paper containing 80% Mainichi, Asahi, and Yomiuri newspapers (all from 1 to 2 months after printing) and 20% flyers with a turbo cutter and mix with 10% water. Add 10.5 g of sodium oxide, 21 g of 10% sodium silicate (No. 3), 0.7 K hydrogen peroxide, 14 g of 1% deinking agent, and 1.280 g of water, and set the waste paper concentration to 5%.
55 with a capacity hydra pulper (3,00 Orpm)
After processing at ℃ for 20 minutes, 933 g of water was added to dilute the waste paper concentration to 3%, and the mixture was stirred for 5 minutes to completely disintegrate it. Next, 4,666 g of water was added to the completely disintegrated paper stock, and the ink was removed using the first method on a sample diluted to a waste paper concentration of 1%.

(2) Removal of ink (A) Cleaning method The sample from (1) above was filtered through an 80-mesh sieve,
Furthermore, water is added so that the concentration of recycled pulp is 1%.
Carbon was removed by filtering again through an 80 mesh sieve.

Water was added to the washed recycled pulp to give a pulp concentration of 1%, and the pulp was hand-sheeted using a Tarapee standard sheet machine to obtain a valve sheet.

(B) Floating method The sample from (1) above was injected into a 5Q fluorite floatator, floated for 10 minutes, the carbon aggregates in the upper layer were removed, and the valve seat was made by hand using a Tarapee standard sheet machine. I got it.

Table 2 shows the evaluation results by the cleaning method, and Table 3 shows the evaluation results by the flotation method.

Deinking effect evaluation method Whiteness: The reflectance was measured using a photoelectric reflectance meter, assuming that the reflectance of magnesium oxide was 100. The number in the table is 5
This is the average value of points x 5 sheets.

b value: Based on the Lab color difference formula of JIS Z8730.

Count the number of remaining inks using a microscope with a magnification of 40.
It was converted into a value per ld.

From the results in Tables 2 and 3, it can be seen that the examples are superior to the comparative examples in whiteness, b value, and number of remaining inks.

Example 2 In a system where newspaper is made by blending deinking pipe obtained from waste newspaper, the deinking agent N in Example 1 was used.
When 0.3% (based on waste paper) of α4 deinking agent was added to the pulper in the deinking process and the whiteness of the pulp immediately after the floatator was measured, the whiteness was 53.8, compared to the conventional nonylphenol ethylene oxide. Whiteness in case of adduct 49.
It showed better results than 7. Furthermore, when conventional products were used, foaming problems occurred during the papermaking process, but after using the product of the present invention, foaming problems disappeared and production efficiency improved.

Claims (2)

[Claims] (1) A deinking agent characterized by containing an alkylene oxide adduct of an alkylphenol resin as an active ingredient. (2) The alkylene oxide adduct of alkylphenol resin has the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ ... [I] (R is an alkyl group with 4 to 18 carbon atoms,
A mixed polyoxyalkylene group of 2H_4O or C_2H_4O and C_3H_6O or C_4H_■O,
m represents 5-200, and n represents 4-50. ) The deinking agent according to claim 1, which is represented by: