JPH01111086A - Deinking agent for regenerating old paper - Google Patents

Abstract

PURPOSE: To obtain the subject deinking agent capable of giving deinked pulp of high whiteness with slight ink residues by mixing a specific compound with a reaction product from natural fat-and-oil, a polyhydric alcohol and an alkylene oxide in specified proportions. CONSTITUTION: This deinking agent is obtained by mixing (A) a compound of the formula [R1 is a (OH-substituted) 7-21C alkyl or alkenyl; R2 is H, a 1-22C alkyl, alkenyl or acyl; AO is a 2-4C oxyalkylene; (n) is such a number as to be <=2,000 in the overall molecular weight of the compound] with (B) a reaction product from natural fat-and-oil (e.g. coconut oil, lard, fish oil), a polyhydric alcohol (e.g. ethylene glycol), and an alkylene oxide, in the weight ratio A/B of (70:30) to (5:95), pref. (60:40) to (30:70).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a deinking agent used when recycling used paper such as newspapers and magazines. More specifically, when newspapers, magazines, etc. are deinked by the flotation method, deinked pulp with high brightness and a small number of residual inks derived from offset ink is obtained, especially deinked pulp with a small number of unpeeled inks. This invention relates to a deinking agent for recycling used paper.

[Conventional technology and problems]

Although recycling of newspapers, magazines, etc. has been carried out for a long time, it has become especially important recently, and there is also an increasing demand for advanced use of deinked pulp. On the other hand, in recent years, the situation with waste paper has become even more difficult from the perspective of deinking due to changes in printing technology, printing methods, changes in printing ink components, weight reduction, etc., and improvements have also been made to equipment to further promote deinking. are being added.

Chemicals traditionally used to separate and remove ink and other impurities from waste paper include alkaline agents such as caustic soda, sodium silicate, and sodium phosphate, and bleaching agents such as hydrogen peroxide, hyposulfite, and hypochlorite. agent, DTPA, EDT^
There are metal ion sequestering agents such as, and along with these agents, anionic activators such as alkylbenzene sulfonates, higher alcohol sulfate ester salts, α-olefin sulfonates, dialkyl sulfosuccinates, higher alcohols, EO adduct of alkylphenol, EO・
Nonionic surfactants such as PO adducts and alkanolamides have been used singly or in combinations of two or more. However, these deinking agents have a low ability to separate and remove ink during flotation treatment, and therefore there has been a demand for the development of a deinking agent that has excellent ink coagulation ability.

In addition, it is difficult to completely separate ink from waste paper, and the presence of ink that has not separated from waste paper, that is, unreleased ink, has become a problem, especially as the use of deinked pulp has expanded and the blending ratio has increased recently. In addition, there is a demand for the development of a deinking agent with poor ink release properties.

[Means for solving problems]

Therefore, the inventors of the present invention have excellent ink removal power from waste paper,
Furthermore, in the flotation treatment process, a deinking agent is used that allows the detached ink to be adsorbed to air bubbles and separated and removed from the pulp fibers to obtain a deinked pulp with high whiteness and a low number of remaining inks, especially a deinked pulp with a low number of unreleased inks. As a result of intensive research to develop this invention, we have completed the present invention.

That is, the present invention provides: (a) a compound represented by the general formula (1) R, COO(-AD juice R2(+) (in the formula (1), R1 may have a DH group as a substituent) an alkyl group or alkenyl group having 7 to 21 carbon atoms,
R2 represents H or an alkyl group, alkenyl group, or acyl having 1 to 22 carbon atoms, AO represents an oxyalkylene group having 2 to 4 carbon atoms, and n is a number such that the overall molecular weight is 2.000 or less. ) and (b) deinking for used paper recycling, which is made by mixing reaction products of natural oils and fats, polyhydric alcohols, and alkylene oxides in a weight ratio of (a)/(b) = 70/30 to 5/95. The purpose is to provide an agent for

The compound represented by the general formula (1) according to the present invention is critical, and even if it is a compound similar to this, the compound represented by the general formula (1)
Compounds that do not fall under the above category cannot achieve the significant effects of the present invention. Therefore, the limitations and numerical values of the functional groups represented by general formula (1) are extremely important. For example, instead of R, COO- group, R, 0- group (R, is the same as the condition of general formula (1))
Compounds consisting of these are inferior in ink collection and ink release properties during flotation.

Examples of the alkylene oxide constituting the oxyalkylene group include ethylene oxide, propylene oxide, butylene oxide, etc., and two or more types of alkylene oxides may be added. The addition of two or more alkylene oxides can be carried out by random addition or block addition, but random addition or block addition of ethylene oxide and alkylene oxides other than ethylene oxide is preferred.

R2 is H or an alkyl group having 1 to 22 carbon atoms, an alkenyl group or an acyl group, and H1 is preferably a methyl group or an acyl group having 8 to 22 carbon atoms.

Also, it is important that the total molecular weight is 2.000 or less,
If it exceeds 2.000, the ink collection and foaming properties during flotation will be poor, making it impossible to obtain a high-quality regenerated valve.

Next, the reaction product (b) will be explained.

Natural oils and fats used in the present invention include vegetable oils such as coconut oil, palm oil, olive oil, soybean oil, rapeseed oil, and linseed oil, animal oils such as lard, beef tallow, and bone oil, fish oils, and hydrogenated and semi-hardened oils thereof. Further examples include recovered oils obtained in the refining process of these oils and fats.

Polyhydric alcohols include ethylene glycone propylene glycol, trimethylene glycol, butylene glycol, glycerin, trimethylolpropane,
Examples include trimethylol ethane, 1.2.4-butanetriol, 1.2.6-hexanetriol, 1.1.1-)limethylolhexanonopepentaerythritol, and tetramethylolcyclohexanonopediglycerin.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, and the like. The alkylene oxides can be added by mixing (random addition) or sequentially adding (block addition), but random addition or block addition of ethylene oxide and alkylene oxides other than ethylene oxide is preferred.

The mixing ratio of natural oil and fat and polyhydric alcohol is 1:0 in molar ratio.
．． The ratio is 1 to 1:3, preferably 1:0.3 to 1:2.

Alkylene oxide is the sum of natural oil and polyhydric alcohol.
It is preferable to use 5 mol or more, especially 20 to 100 mol per mol. If the amount is less than 5 moles, the ink release property from waste paper and the foaming property during flotation treatment will be reduced.

The reaction between natural fats, polyhydric alcohols, and alkylene oxides is usually carried out by blowing alkylene oxide into a mixture of natural fats, polyhydric alcohols, and natural oils mixed in the above proportions, and reacting with the addition reaction of the alkylene oxides between the natural fats and polyhydric alcohols. However, even if you change the order and react the alkylene oxide with the polyhydric alcohol first, and then react it with the natural oil, you cannot obtain a product with the same deinking performance. It will be done.

The addition reaction is not particularly limited, and can be carried out under the conditions of the commonly performed alkylene oxide addition reaction to a compound having active hydrogen. For example, a catalytic amount of an alkaline substance is added to a mixture of natural oils and fats and polyhydric alcohol prepared at the above molar ratio;
This can be achieved by reacting alkylene oxide at 0°C and 1 to 3 kg/cm' for several hours.

In the deinking agent of the present invention, the blending ratio of components (a) and (b) is (a)/(b) = 70/30 to 5/9 by weight.
5, preferably 60-40-30/70.

If it is outside this range, the balance between ink cohesiveness and foamability during flotation will be disrupted, making it impossible to obtain pulp with high whiteness and a low number of remaining inks. That is, (a)/(b
) If it is larger than 70/30, it will result in high foaming due to flotation, large outflow of pulp, and poor ink cohesiveness. Furthermore, when (a) b) is smaller than 5/95, the foaming property becomes low during flotation, and the agglomerated ink cannot be efficiently removed from the system, making it impossible to obtain high-quality deinked pulp. As a result, a large amount of unpeeled ink is present outside the above range, and only a low-quality deinking valve is obtained.

The deinking agent of the present invention may be added separately to either the waste paper disintegration process, the aging tower process, or both processes, but it is most effective when added to the waste paper disintegration process.

The amount added is preferably 0.2 to 1.0% by weight based on the raw waste paper. Further, the deinking agent of the present invention can also be used in combination with known deinking agents that have been commonly used.

[Examples and effects of the invention]

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples.

Example-1 First, component (b) of the present invention (sample 1) was prepared with the composition shown in Table-1.
-7) were prepared. Next, 2 x 5 pieces of recycled newspaper paper were
After shredding into cm pieces, put a certain amount of it into a tabletop disintegrator, and add water and caustic soda (based on raw materials) 1.0% (based on weight, the same applies hereinafter), sodium silicate (based on raw materials) 3.0%, Add 3.0% of 30% hydrogen peroxide solution (based on raw materials) and 0.4% of various deinking agents shown in Table 2 (based on raw materials), bulb concentration 5%, and 55°C.
After disintegration for 20 minutes, the mixture was aged at 50° C. for 60 minutes. Add the condensate to dilute the bulb concentration to 1.0%, and
1□ (based on raw materials) 1.0% was added and subjected to flotation treatment at 30°C for 10 minutes. After the valve slurry after flotation was concentrated to a concentration of 6%, water was added to dilute it to a concentration of 1%, and a valve seat was produced using a TAPPI sheet machine. The whiteness of the obtained valve sheet was measured using a colorimeter, and the number of remaining inks and the number of unpeeled inks was measured using an image analyzer (126x magnification). Table 2 shows the results.
Shown below.

Table 1 (Note) Wealth: EO is ethylene oxide, PO is propylene oxide, and 80 is butylene oxide.

Example-2 After shredding Nanchu recycled newspaper waste paper into 2 x 5 cm pieces, put a certain amount of it into a tabletop disintegrator, and add water, caustic soda (based on raw materials) 1.0%, and sodium silicate No. 3 (based on raw materials). 0.5%, table-
Add 0.4% of the various deinking agents (based on raw materials) shown in 3, pulp concentration 5%, 45 ° C., after 20 separations, the pulp concentration was 18
%, and add 1 part of caustic soda (to raw material) to it.
．． 5%, sodium silicate No. 3 (based on raw materials) 2.5%, and 30% hydrogen peroxide solution (based on raw materials) 3.0% and mixed.
Aging treatment was performed at 5° C. for 90 minutes at a pulp concentration of 15%. After that, water was added so that the pulp concentration was 4%, and the pulp was disintegrated for 5 minutes using a tabletop disintegrator.Water was then added to dilute the pulp to 1.0%, and 1.0% of CaC12 (based on the raw material) was added. Then, a flotation treatment was performed at 30° C. for 10 minutes. After the pulp slurry after flotation was concentrated to a concentration of 6%, water was added to dilute it to a concentration of 1%, and a valve sheet was produced using a TAPPI sheet machine. The whiteness of the obtained valve seat was measured using a colorimeter and an image analysis device (
The number of remaining inks and the number of unpeeled inks were measured at a magnification of 126 times.

The results are also shown in Table 3.

Claims (1)

[Claims] 1 (a) A compound represented by general formula (1) ▲ Numerical formula, chemical formula, table, etc. ▼ (1) (In formula (1), R_1 has an OH group as a substituent) R_2 represents H or an alkyl group, alkenyl group or acyl having 1 to 22 carbon atoms; AO represents an oxyalkylene group having 2 to 4 carbon atoms; (n is a number such that the overall molecular weight is 2,000 or less.) and (b) reaction product of natural oil, polyhydric alcohol, and alkylene oxide at a weight ratio of (a)/(b) = 70/30. A deinking agent for waste paper recycling made by mixing at a ratio of ~5/95. 2. The deinking agent for waste paper recycling according to claim 1, wherein the reaction product is obtained by adding 5 moles or more of alkylene oxide to 1 mole of the sum of natural oil and fat and polyhydric alcohol. 3. The deinking agent for waste paper recycling according to claim 1, wherein the mixing ratio of natural oil and fat to polyhydric alcohol is 1:0.1 to 1:3 in molar ratio.