JPH05263383A - Ink-removing agent - Google Patents

Abstract

PURPOSE:To obtain an ink-removing agent containing a specific compound, excellent in the ink-releasing force in a floating process and having a sufficient ink-catching action and a proper foaming action. CONSTITUTION:This ink-removing agent contains a compound of the formula (X<1>, X<2> are independently H, hydrocarbon group, or X<1>, X<2> are combined to each other to form a CH=CH-CH=CH; R<1>, R<2> are independently lower alkyl), e.g. dimethyl phthalate. The content of the compound of the formula is 10-50wt.%, preferably 20-40wt.%, based on the ink-removing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention has the general formula

[Chemical 2] [In the formula, X ¹ and X ² may each be hydrogen or a hydrocarbon group, or may be bonded together to form —CH═CH—CH═CH—, and R ¹ and R ² are each a lower alkyl group. Indicates. ] The present invention relates to a deinking agent containing a compound represented by the following and widely used in the recycling of used paper [particularly when manufacturing recycled paper from used paper including used Xerox paper (electrophotographic copy)].

[0002]

2. Description of the Related Art Recently, the range of applications for recycled paper such as printing paper for newspapers and magazines, and replacement of bleached, kraft, and pulp has expanded, and as a result, it has high whiteness and bright color tone. However, recycled paper with less residual ink has been demanded. However, in response to the diversified needs of printed materials, the diversification of printing techniques and printing inks has led to an increase in the ratio of recovered printed materials that contain difficult-to-deink printed materials. In newspaper printing as well, since letterpress printing is shifting to offset printing, the resin component in the ink also increases, and deinking tends to be difficult. Conventionally, for the recycling of used paper, alkali metal hydroxides such as caustic soda, sodium carbonate and sodium silicate, inorganic chemicals such as carbonates and silicates, bleaching agents such as hydrogen peroxide and hypochlorite, Along with sequestering agents such as ethylenediaminetetraacetate and diethylenetriaminepentaacetate, polyoxyethylene alkyl ether,
Polyoxyethylene alkyl phenyl ether, polyoxyethylene polyoxypropylene block polymer,
Non-ionic surfactants such as higher fatty acid alkanol amides and deinking agents prepared by mixing anionic surfactants such as alkylbenzene sulfonate, higher alcohol sulphate, higher alcohol ether sulphate and dialkyl sulfosuccinate, alone or in combination of two or more Has been used. Examples of commercially available deinking agents include Meisanol PS61 (manufactured by Meisei Chemical Co., Ltd.), DI-8.
00 (manufactured by Kao Corporation), Tonacrine (Japan Emulsifier Co., Ltd.)
Made), Nescoa FW-173 (manufactured by Toho Kagaku Co., Ltd.), Lipotol LH700 (manufactured by Nika Kagaku Co., Ltd.), Adecanol R
P-882 (manufactured by Asahi Denka Co., Ltd.), Liptor FR / 2
03C (manufactured by Lion Co., Ltd.), Haritop P-100 (manufactured by Harima Kasei Co., Ltd.), Kuridash 305 (Kurita Industry Co., Ltd.)
Made) etc. Further, when a used paper is recycled, it is bleached after applying a deinking agent to the used paper, and there is an example in which a terephthalic acid ester is used as a bleaching agent for the bleaching (JP-A-3-173847).

[0003]

However, it is necessary that the deinking agent has an ink peeling action, a foaming action, and a desorption ink aggregation action. One of the major drawbacks is that only a low-quality recycled paper can be obtained because either or both of the peeling action of the ink and the aggregating action of the desorbed ink are insufficient. Therefore, attempts have been made to use mineral oil, higher fatty acids or salts thereof as deinking agent components for the purpose of increasing the aggregation action of desorbed ink during the flotation (ink floating selection) step. However, mineral oil has many problems in working due to its low flash point and strong odor, and also has the drawback that sufficient effect cannot be obtained unless added in a large amount because the coagulation action of ink is insufficient. On the other hand, higher fatty acids or salts thereof have a strong ink aggregating action, but have a weak foaming action, and the ink flocculated and floated in the flotation process is not sufficiently removed and remains in the product, causing troubles such as ink spots. There was a drawback. Further, it has been attempted to use a nonionic surfactant or an anionic surfactant together as a foaming agent for the purpose of compensating for these drawbacks, but since these foaming agents are components that originally act as a dispersant. However, this causes a strong carbon aggregation action of fatty acids, resulting in insufficient ink removal. Further, the conventional deinking agent has a drawback that its application range is narrow. That is, DI-800, Meisanol P
S61 and the like have a high deinking effect on waste newspaper, but have a low deinking effect on toner ink, and Tonacrine and the like have a high deinking effect on toner ink. There is a drawback that the deinking effect on used paper is low. Therefore, an object of the present invention is to have an excellent ink separation force in the flotation step, to have a sufficient ink collecting action and an appropriate foaming action,
Moreover, it is to provide a deinking agent that can be widely applied to all kinds of used paper.

[0004]

DISCLOSURE OF THE INVENTION As a result of earnest research for achieving the above object, the present inventors have found that the partial structure

[Chemical 3] The present invention has been completed by discovering that dimethyl phthalate or its structurally similar compounds, which are characterized in that (R ¹ and R ² have the same meanings as described above), have an excellent deinking effect. That is, the present invention has the general formula

[Chemical 4] [In the formula, X ¹ and X ² may each be hydrogen or a hydrocarbon group, or may be bonded together to form —CH═CH—CH═CH—, and R ¹ and R ² are each a lower alkyl group. Indicates. ] It is related with the deinking agent characterized by containing the compound represented by these. In the above general formula, X ¹ and X ²
The hydrocarbon group represented by is, for example, a linear or branched C _1-6 alkyl group such as methyl, ethyl, propyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl, hexyl, for example, vinyl, Linear or branched C such as 1- or 2-propenyl, 1- or 2-butenyl, 1- or 2-pentenyl
_2-6 alkenyl groups, eg ethynyl, 1- or 2
-Propynyl, 1- or 2-butynyl, 1- or 2
A linear or branched C _2-6 alkynyl group such as pentynyl is used. It is preferred that X ¹ and X ² are each hydrogen or bonded together to form —CH═CH—CH═CH—.

Examples of the lower alkyl group represented by R ¹ and R ² include linear or branched C such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl and hexyl. _{A 1-6} alkyl group or the like is used. Of these, methyl is preferred. Specific examples of the compound (I) represented by the above general formula include lower alkyl phthalates such as dimethyl phthalate, diethyl phthalate, dipropyl phthalate and dibutyl phthalate, dimethyl maleate, diethyl maleate, Lower alkyl maleic acid esters such as dipropyl maleate and dibutyl maleate, lower alkyl fumarate esters such as dimethyl fumarate, diethyl fumarate, dipropyl fumarate and dibutyl fumarate are used. Especially, the good deinking effect can be obtained by using dimethyl phthalate. Compound (I)
May be any commercially available product.

The deinking agent of the present invention can be produced by a conventional method using one or more compounds (I).
The ratio of the compound (I) contained is 10 to 5 with respect to the deinking agent.
It is 0% by weight, preferably 20 to 40% by weight. A more excellent deinking effect can be exhibited by appropriately adding a surfactant during the production of the deinking agent. The surfactant to be used may be any of a cationic surfactant, an anionic surfactant and a nonionic surfactant, and may be used alone or in combination of two or more kinds. The cationic surfactant may be, for example, any of an alkylamine salt, a quaternary ammonium salt and the like, and the above cationic surfactants may be used alone or in combination of two or more. The anionic surfactant may be, for example, any of alkylbenzene sulfonate, higher alcohol sulfate, higher alcohol ether sulfate, dialkyl sulfosuccinate, higher fatty acid alkali metal salt, etc., and the anionic surfactant may be used alone or You may mix and use a kind or more. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene polyoxypropylene ether, polyoxyethylene alkyl ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene. Any nonionic surfactant such as polyoxypropylene block polymer and higher fatty acid alkanol amide may be used, and the above nonionic surfactants may be used alone or in combination of two or more. Among them, it is preferable to add polyoxyethylene alkyl ether. In addition, to the deinking agent of the present invention, any additive generally used for producing a deinking agent such as an excipient (eg, water, starch, glucose, etc.) can be added. Specifically, the compound
(I) is usually 10 to 50% by weight, preferably 20 to 40
% By weight, surfactant is usually 5 to 90% by weight, preferably 10 to 80% by weight, other additives are usually 0 to 30% by weight.
The deinking agent of the present invention can be produced by, for example, adding 5% by weight, preferably 5% by weight to 20% by weight.
As a mixing method, any generally known method may be used. For example, in a vessel such as a melting pot, the stirring speed is usually 20 to 10,000 rpm, preferably 20 to 3,000 rpm.
Mixing and stirring at 0 rpm, more preferably 200 to 2,000 rpm. The mixing temperature is usually 10 to 80 ° C., preferably 1
It is 5-60 degreeC. The mixing time is usually 0.5 to 2 hours,
It is preferably 0.5 to 1 hour. The deinking agent thus obtained has an excellent ink releasing force, and has a sufficient ink collecting action and an appropriate foaming action.
All types of waste paper, including high quality waste paper such as structural waste paper, colored waste paper, and quality waste paper such as newspaper waste paper and magazine waste paper (including compression molded waste paper. Compression molded waste paper is compression molded by a compression molding machine. Recycled paper) and any cloth such as silk or cotton. Above all, it can exert an excellent deinking effect on waste paper. This characteristic was not found at all in the above-mentioned commercially available deinking agent.

The deinking agent of the present invention can be used in the same manner as a conventional deinking agent, and the amount used varies depending on the target, but when used for recycling used paper, it depends on the type of used paper. Although it is slightly different, it is usually 0.01-
It is 5.0% by weight, preferably 0.05 to 1.0% by weight. Further, when the deinking agent of the present invention is used, like the conventional deinking agent, alkali metal hydroxides, carbonates and silicates such as caustic soda, sodium carbonate, and sodium silicate are recycled when used paper is recycled. Chemicals, hydrogen peroxide, bleaching agents such as hypochlorous acid, toner deinking agents for waste ink such as tonacrine (manufactured by Nippon Emulsifier Co., Ltd.), fatty acids such as Lipotol LH-700 (manufactured by Nikaka Co., Ltd.) A commercially available deinking agent such as a system deinking agent may be appropriately added. As described above, by using the deinking agent of the present invention, high quality recycled paper can be obtained.

[0008]

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but this does not limit the present invention. Example 1 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 5,000 rpm for 30 minutes. Next, 10 kg of water was added and mixed and stirred at about 20 ° C. and a stirring speed of about 5,000 rpm for 30 minutes to obtain a product.

Example 2 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 5,000 rpm for 30 minutes. Next, Sunclear PF-11 (Sanyo Kasei)
5 kg and Brofan 128 Extra (Sanyo Kasei)
(Manufactured by Co., Ltd.) 5 kg, about 20 ℃, stirring speed about 5,000
The product was obtained by mixing and stirring at 0 rpm for 30 minutes.

Example 3 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 5,000 rpm for 30 minutes. Next, Sunclear PF-11 (Sanyo Kasei)
5 kg and Brofan 128 Extra (Sanyo Kasei)
(Manufactured by Co., Ltd.) 5 kg, about 20 ℃, stirring speed about 5,000
The product was obtained by mixing and stirring at 0 rpm for 30 minutes.

Example 4 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes. Next, 10 kg of water was added and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes to obtain a product.

Example 5 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes. Next, Sunclear PF-11 (Sanyo Kasei Co., Ltd.)
5 kg and Brofan 128 Extra (Sanyo Kasei Co., Ltd.)
5 kg) and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes to obtain a product.

Example 6 70 kg of Sunclear PF-4 (manufactured by Sanyo Kasei Co., Ltd.) in a melting pot
And 20 kg of dimethyl phthalate (manufactured by Kurogane Kasei Co., Ltd.) were added and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes. Next, Sunclear PF-11 (Sanyo Kasei Co., Ltd.)
5 kg and Brofan 128 Extra (Sanyo Kasei Co., Ltd.)
5 kg) and mixed and stirred at about 20 ° C. and a stirring speed of about 500 rpm for 30 minutes to obtain a product.

[0014]

[Comparative example]

Comparative Example 1 Dimethyl maleate, diethyl maleate, dimethyl terephthalate, and dimethyl phthalate were used in water containing a very small amount of a surfactant (Sunclear PF-11).
Diluted to 00%, 10%, 1%, 0.1% and 0.01%. On the Xerox waste paper which copied the whole surface in black,
Each diluted deinking agent was dropped one by one using a dropper. After 3 minutes, the dropped portion was rubbed with a tissue paper, and the peeled state of the rubbed portion was visually observed. The results are shown in [Table 1] below.

[Table 1] From Table 1, it can be seen that dimethyl phthalate, dimethyl maleate and diethyl maleate have an excellent peeling effect on the toner ink. On the other hand, it can be seen that dimethyl terephthalate used as a bleaching agent has no peeling effect on the toner ink.

Comparative Example 2 Deinking agent manufactured in Example 2, commercially available deinking agent DI-80
0, Meisanol PS61 and Tonacrine were diluted to 10%, 1% and 0.1% respectively with water. Each of the diluted deinking agents was dropped one by one with a dropper onto Xerox waste paper whose entire surface was copied in black. After 3 minutes, the dropped portion was rubbed with a tissue paper, and the peeled state of the rubbed portion was visually observed. The results are shown in [Table 2] below.

[Table 2] From [Table 2], the 10% diluted solution of the deinking agent of the present invention is superior in the peeling effect to the toner ink as compared with the commercially available DI-800 and Meisanol PS61. It can be seen that it has an effect equivalent to that of the drug, tonacrine.

Comparative Example 3 Imitation waste paper and 40 g of colored waste paper were cut into 5 cm in length and 0.5 cm in width by using a shredder, and then water at 25 ° C. 960 m
It was put into a mixer together with 1 and crushed to obtain a waste paper solution having a waste paper concentration of 4% by weight. Then, the deinking agent of the present invention produced in Example 2, a commercially available deinking agent DI-800, and Meisanol PS.
61% and tonacrine were added to each waste paper solution in an amount of 0.05% by weight, 0.10% by weight and caustic soda in an amount of 0.5% by weight, and then disintegrated at 25 ° C for 2 minutes. 25 this
Hold at 2 ° C for 2 hours. Then, each suspension was diluted with 25 ° C. water so that the concentration of waste paper was 1% by weight. This used paper diluted suspension is floatator (FW type flotation tester,
Kyoshin Sangyo Co., Ltd.) was used for flotation treatment at 25 ° C. for 10 minutes to remove the foam liquid (floss). After the treatment, the obtained pulp suspension was filtered with a suction filter and hand-sheeted into a sheet. The number of residual inks of the obtained pulp sheet was measured using a stereoscopic microscope (× 20, manufactured by Olympus). The results are shown in [Table 3] below.

[Table 3] From [Table 3], the pulp sheet treated with the deinking agent of the present invention has a smaller residual ink number than any of the pulp sheets treated with commercially available DI-800, Meisanol PS61 and Tonacrine. It can be seen that the agent has a better deinking effect on high-quality waste paper than a commercial deinking agent.

COMPARATIVE EXAMPLE 4 40 g of a newspaper was 5 cm in length and 0.5 cm in width by using a shredder.
It was cut into four sides, put into a mixer with water at 25 ° C. and crushed to obtain a used paper suspension having a used paper concentration of 4% by weight. To this used paper suspension, the deinking agent of the present invention produced in Example 2, the commercially available deinking agent DI-800, Meisanol PS61 and tonacrine were added in an amount of 0.3% by weight, caustic soda 1.5% by weight, and silicic acid. After adding 1.5% by weight of soda and 1.0% by weight of hydrogen peroxide, defibration treatment was performed at 25 ° C. for 2 minutes. This was kept at 25 ° C. for 2 hours. Then, each suspension was diluted with water at 25 ° C. so that the concentration of waste paper was 1% by weight. This used paper diluted suspension was subjected to a flotation treatment at 25 ° C. for 8 minutes using a floatator (FW type flotation tester, manufactured by Kyoshin Sangyo Co., Ltd.) to remove a foam liquid (floss). After the treatment, the obtained pulp suspension was filtered with a suction filter and hand-sheeted into a sheet. The Hunter whiteness and the number of remaining inks of the obtained pulp sheet were measured. The measurement of pulp brightness is
The measurement was performed using a Hunter whiteness meter (CM-8P type, manufactured by Murakami Co., Ltd.). The measurement of the number of remaining inks was performed in the same manner as in Comparative Example 3. The obtained results are shown in [Table 4] below.

[Table 4] As shown in Table 4, the pulp sheet treated with the deinking agent of the present invention has higher whiteness and less residual ink number than any of the pulp sheets treated with commercially available DI-800, Meisanol PS61 and Tonacrine. It can be seen that the deinking agent of the present invention has a better deinking effect on newspaper waste paper than a commercially available deinking agent.

[0018]

The deinking agent of the present invention is a toner ink waste paper,
A wide range of excellent deinking effects can be exhibited for the recycling of all types of high-quality waste paper and newspaper waste paper.

Claims (4)

[Claims] 1. A general formula: [In the formula, X ¹ and X ² may each be hydrogen or a hydrocarbon group, or may be bonded together to form —CH═CH—CH═CH—, and R ¹ and R ² are each a lower alkyl group. Indicates. ] A deinking agent comprising a compound represented by: 2. A deinking agent containing dimethyl phthalate. 3. The deinking agent according to claim 1, which contains a surfactant. 4. The deinking agent according to claim 3, wherein the surfactant is a nonionic surfactant.