JP2761948B2 - Deinking agent for recycled paper - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a deinking agent used for recycling printed waste paper such as newspapers, magazines, and leaflets. More specifically, when deinking newspapers and magazines by the flotation method,
The present invention relates to a deinking agent capable of improving ink collecting properties and obtaining a deinked pulp having high whiteness and little residual ink.

(Prior art) Recycling of newspapers, magazines, etc. has been practiced for a long time, but the importance of the effective use of waste paper has been increasing, especially in recent years, due to the protection of forest resources and the expanded use of deinked pulp. I have.

In order to recycle printed waste paper, the printed waste paper is usually treated in a disintegrator with an alkaline agent such as caustic soda and sodium silicate and a deinking agent, and, if necessary, a bleaching agent such as hydrogen peroxide and hyposulfite.
2. Description of the Related Art A method is widely used in which deflocculation is carried out together with a sequestering agent such as EDTA and DTPA, ink is detached from pulp, and the detached ink is separated from pulp by a water washing treatment or a flotation treatment.

The deinking agent is roughly divided into a dispersing deinking agent that aims to remove the detached ink finely dispersed outside the system, and a detached ink that is removed out of the system in a state where the detached ink is aggregated to some extent. There is an agglomerated deinking agent for the purpose of cleaning, and among them, an agglomerated deinking agent capable of further increasing the whiteness of recycled pulp is widely used.

Examples of deinking agents include anionic surfactants such as alkylbenzene sulfonates, higher alcohol sulfates, and α-olefin sulfonates, and nonionic surfactants such as polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl allyl ethers, and fatty acid alkanolamides. Alternatively, higher fatty acids and the like have been used alone or in combination of two or more. However, higher fatty acids in conventional deinking agents have a high ink aggregating effect, but have a problem in that the penetration into the pulp and the ink releasing effect are low and a sufficient deinking effect cannot be obtained, and alkylene oxides such as polyoxyalkylene alkyl ethers are used. Adducts (for example, JP-B-64-11756, JP-A-63-3)
No. 03190 and Japanese Patent Application Laid-Open No. 1-111086) have a high effect of penetrating into pulp and dispersing and dispersing the ink, but have a poor affinity for the ink, so that the effect of coagulating the ink is not yet sufficient.

(Problems to be Solved by the Present Invention) In particular, in recent waste paper, the ink composition has changed due to the improvement of printing technology, especially offset printing ink, and drying oil and thermosetting resin have been used. The ink film was hardened hard, and it was difficult to separate the ink with the conventional deinking agent and separate it from the pulp, so that high-quality deinked pulp could not be obtained.

Further, with the expansion of uses of deinked pulp, deinked pulp having higher whiteness and less residual ink is required.

Accordingly, an object of the present invention is to provide a deinking agent capable of easily performing high deinking even on used paper that has become difficult to separate and separate.

(Means for Solving the Problems) In order to achieve the above object, the present inventors need a deinking agent that has a large ink peeling effect, an ink aggregation effect, and an appropriate foaming property. In view of the above, as a result of intensive studies, they have found that a product obtained by adding an alkylene oxide to a specific dicarboxylic acid or dicarboxylic acid monoester has the above-mentioned necessary physical properties, and completed the present invention.

That is, the present invention provides the following formula (I) (However, one of X is COO (AO) _n H and the other is H or C
A n = 1 to 200 in H _3, AO is an alkylene oxide, Y
Is (AO) _m H or R and m = 1 to 200, and R has 1 to 18 carbon atoms.
Which is an alkylene oxide adduct of a dicarboxylic acid or a dicarboxylic acid monoester of the formula (1).

The dicarboxylic acid of the basic skeleton used in the present invention has the formula (II) (X is the same as the definition of the formula (1)), which is known in JP-A-49-66659 and US Pat. No. 3,899,476, and generally has a trade name of DIACID-1550 (supplier:
Harima Chemicals, Inc. 90% of dicarboxylic acid, 9% of monocarboxylic acid, and a mixture of other unsaponifiable compounds can be used. The monoester of dicarboxylic acid is a dicarboxylic acid represented by the above formula (II). Primary acid carboxyl machine
Alcohol represented by ROH (R is an alkyl group having 1 to 18 carbon atoms, preferably 1 to 15 carbon atoms) such as methanol, isopropanol, butanol, hexanol, octanol, lauryl alcohol, and various other synthetic alcohols alone or in combination. A product obtained by reacting an alcohol by a known method can be used. The present invention does not limit the incorporation of small amounts of monomeric acids.

Examples of the alkylene oxide used in the present invention include ethylene oxide, propylene oxide, and butylene oxide.One or more kinds may be added, and the addition of two or more kinds can be performed by random addition or block addition. Random or block addition is most preferred with a combination of ethylene oxide and propylene oxide. The addition mole number of the alkylene oxide is 1 to 200 moles, and if it is 200 moles or more, the foaming property of the flotation step in deinking is reduced, and the cohesiveness of the peeled ink is impaired, and high-quality recycled pulp is obtained. Absent. The addition mole number of the alkylene oxide is particularly preferably from 10 to 120 moles. The addition reaction is not particularly limited.For example, an alkaline substance is added as a catalyst to the dicarboxylic acid or dicarboxylic acid monoester, and 100 to 200
An alkylene oxide is blown at 1 ° C. and 1 to 5 kg / cm ² and reacted for several hours to obtain an addition product.

The place where the deinking agent of the present invention is added is preferably a step before a pulper or an aging tower, but it can also be added to a floatator. Although the present deinking agent alone is sufficiently effective, other deinking agents, for example, nonionic activators such as anionic activators and polyoxyalkylene alkyl ethers and higher fatty acids may be used in combination.

(Effects) Since the deinking agent of the present invention has an alkylene oxide added to a specific dicarboxylic acid or dicarboxylic acid monoester, it not only has excellent ink penetration and releasability, but also has good foaming properties and ink aggregation. Since the properties of the pulp are very superior to those of the conventional deinking agents, high-quality recycled pulp with high whiteness and little residual ink can be easily obtained.

(Examples) Hereinafter, the present invention will be specifically described based on examples.

Example 1 DIACID-1550 having an average molecular weight of 352.5 as a dicarboxylic acid
(Distributor: Harima Kasei Kogyo Co., Ltd.) Put 352.5 g in a pressure-resistant reaction vessel, add 2.1 g of caustic potash as a catalyst, heat to 170 ° C., replace the inside of the vessel with nitrogen gas, degas under reduced pressure, and then 264.3 g of ethylene oxide Was blown at a pressure of 1 to 5 kg / cm ² for 3 hours to obtain a deinking agent having 6 mol of ethylene oxide adduct.

Example 2 A deinking agent was obtained in the same manner as in Example 1 except that the reaction conditions were changed to 881.0 g of ethylene oxide.

[Example 3] DIACID-1550 (sold by Harima Kasei Kogyo Co., Ltd.) and an excess amount of methyl alcohol were reacted under reflux of methanol using a sulfuric acid catalyst to form a monoester, and the excess methyl alcohol was removed under reduced pressure. After that, purification was performed by molecular distillation to obtain a monoester having an acid value of 113 and an average molecular weight of 367. 180.0 g of this monoester was placed in a pressure-resistant reaction vessel, 1.1 g of caustic was added as a catalyst, heated to 170 ° C., the inside of the vessel was replaced with nitrogen gas, and after degassing under reduced pressure, 649.0 g of ethylene oxide was added at 1 to 5 kg / cm.
Blowing reaction was carried out for 3 hours at ² and then 285.3 g of propylene oxide was blown at a pressure of ¹ to 5 kg / cm ² for 5 hours to obtain a deinking agent with addition of 30 mol of ethylene oxide and 10 mol of propylene oxide.

Example 4 DIACID-1550 and octyl alcohol were dehydrated at 200 to 250 ° C. to form a monoester, and then excess octyl alcohol was removed under reduced pressure to obtain a monoester having an acid value of 89 and an average molecular weight of 465. 180.0 g of this monoester was placed in a pressure-resistant reaction vessel, 1.1 g of caustic potassium was added as a catalyst, heated to 170 ° C., the inside of the vessel was replaced with nitrogen gas, and after degassing under reduced pressure, 682.5 g of ethylene oxide was pressured at 1 to 5 kg / cm ^2. For 3 hours, and then 337.5 g of propylene oxide at a pressure of 1 to 5 k.
Blowing reaction was performed at g / cm ² for 5 hours to obtain a deinking agent to which 40 mol of ethylene oxide and 15 mol of propylene oxide were added.

Example 5 DIACID-1550 and lauryl alcohol were reacted at 200 to 250 ° C. to form a monoester, and excess lauryl alcohol was removed under reduced pressure to obtain a monoester having an acid value of 78 and an average molecular weight of 521. 180.0 g of this monoester was placed in a pressure-resistant reaction vessel, 1.1 g of caustic potassium was added as a catalyst, and the mixture was heated to 170 ° C.
After the inside of the vessel was replaced with nitrogen gas and degassed under reduced pressure, 609.0 g of ethylene oxide was blown in at a pressure of 1 to 5 kg / cm ² for 3 hours, and then 100.4 kg of propylene oxide was pressured at 1 to 5 kg / c.
m ² for 5 hours to give ethylene oxide 40
A deinking agent was obtained with the addition of 5 moles and 5 moles of propylene oxide.

Example 6 DAICID-1550 having an average molecular weight of 352.5 as a dicarboxylic acid
Into a pressure-resistant reaction vessel, and 0.1% of caustic potassium was used as a catalyst.
7 g, heated to 170 ° C., the atmosphere in the container was replaced with nitrogen gas, and after degassing under reduced pressure, 862.3 g of ethylene oxide was pressured at 1 to 5 kg / cm.
Blowing reaction was carried out for ² hours at ² , followed by blowing reaction of 189.5 g of propylene oxide at a pressure of 1 to 5 kg / cm ² for 4 hours to obtain a deinking agent with addition of 60 mol of ethylene oxide and 10 mol of propylene oxide.

Example 7 A deinking agent was prepared in the same manner as in Example 6, except that propylene oxide was blown in and ethylene oxide was blown in as a reaction condition, followed by addition of 10 moles of propylene oxide and 60 moles of ethylene oxide.

Example 8 A deinking agent obtained by random addition of 60 mol of ethylene oxide and 10 mol of propylene oxide was obtained in the same manner as in Example 6, except that ethylene oxide and propylene oxide were simultaneously blown for 6 hours as reaction conditions.

Example 9 A deinking agent obtained by adding 40 mol of ethylene oxide and 6 mol of butylene oxide was obtained in the same manner as in Example 6, except that the alkylene oxide was changed to 574.8 g of ethylene oxide and 141.1 g of butylene oxide as reaction conditions.

Example 10 The same procedure as in Example 6 was repeated except that 1724.5 g of ethylene oxide was blown in for 6 hours and 757.9 g of propylene oxide were blown in for 8 hours.
An additional deinking agent of 40 moles and 40 moles of propylene oxide was obtained.

[Comparative Examples 2 to 4] Using oleic acid, stearic acid, and lauryl alcohol in place of the above dicarboxylic acid or dicarboxylic acid monoester, oleic acid (EO) ₂₀ (PO) ₁₀ , stearic acid were obtained by the same reaction as in the example. (EO) ₂₀ (PO) ₁₀ and lauryl alcohol (EO) ₂₅ (PO) ₁₀ were obtained.

[Example of deinking test]

In accordance with J.TAPP Pulp and Paper Test Method No.39-82, a raw material consisting of 80% offset printed newspaper waste paper and 20% leaflet waste paper was 3
Shred to × 3cm, put a certain amount into a pulp disintegrator, add warm water, 1.5% caustic soda, 3.0% sodium silicate 3.0%, 30% hydrogen peroxide 3.0% based on waste paper weight, Table 1 Each of the indicated deinking agents (0.3%) was added, the pulp concentration was 4.0%, the mixture was dissociated for 30 at 50 ° C, and then aged at 50 ° C for 1 hour. Thereafter, water was added to dilute the pulp to a concentration of 1.0%, followed by a flotation treatment at 30 ° C. for 10 minutes. 80 Pulp slurry after flotation
After dehydrating with a mesh wire and concentrating to 5%, water was added to dilute to a pulp concentration of 1.0%, and weighed 100 with a square sheet machine.
A pulp sheet of g / m ² was prepared.

The whiteness of the obtained pulp sheet was measured with a Hunter white light photometer according to JIS P8123. In addition, the indication of the residual carbon amount was obtained by crushing the obtained pulp sheet with a household mixer using a simple method of measuring carbon in deinked pulp.
g in an acetyl bromide / acetic acid (1/3 volume ratio) mixed solution, and dissolve cellulose at 65-70 ° C for 2 hours. Advantech Toyo glass fiber filter (GS25, diameter
After the filter was air-dried, it was measured with a color difference meter. The smaller the residual ink in the obtained recycled pulp sheet, the larger the residual carbon L value.

Table 1 also shows the results. It can be seen that when the deinking agent of the present invention is used, the whiteness and the residual ink are reduced as compared with Comparative Examples 1 to 4.

Claims (1)

(57) [Claims] (1) The following formula (I) (However, one of X is COO (AO) _n H and the other is H or C
A n = 1 to 200 in H _3, AO is an alkylene oxide, Y
Is (AO) _m H or R and m = 1 to 200, and R has 1 to 18 carbon atoms.
And an alkylene oxide adduct of dicarboxylic acid or dicarboxylic acid monoester as a main component.