JP2007314903A - Treating agent for paper-making raw material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treating agent for a paper-making raw material, which is capable of efficiently bonding so-called anion trash existing in a dispersion liquid of paper-making raw material to pulp, etc., by the addition of a small amount of the agent and to suppress the defects and fault generated in the paper and the web break during the paper-making process by the use of the agent. <P>SOLUTION: The treating agent for paper-making raw material is an organic compound having an amidinium group expressed by structural formula (I) (wherein R<SP>1</SP>and R<SP>2</SP>are each independently hydrogen atom or a univalent organic group). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a papermaking raw material treating agent, and in particular, improves the yield of papermaking chemicals and pulp fibers contained in a papermaking raw material dispersion (hereinafter also referred to as pulp slurry), and efficiently captures impurities contained in the system. And a papermaking raw material treating agent that prevents accumulation in the circulating water system.

  In the papermaking industry, it is an issue to improve the yield of papermaking chemicals and pulp fibers contained in pulp slurry, especially fine pulp fibers (hereinafter referred to as fine fibers) that pass without being retained on the papermaking wire. It has become.

  Moreover, in addition to the said chemical | medical agent and a fine fiber, impurities, such as a filler, a pigment, latex, and a hot melt, are also contained in a pulp slurry. These are usually derived from waste paper generated in papermaking, coating, and cutting processes in a paper mill, or from recovered paper that is collected and reused from the market. In particular, in recent years, there has been a tendency to increase the amount of contaminating components mixed in the pulp slurry due to the improved utilization of waste paper.

  Furthermore, from the viewpoints of environmental considerations and resource saving, the so-called closed process, in which water used for papermaking is circulated and reused, is being promoted. It has become.

  The above papermaking chemicals, fine fibers, and impurities are generally called anionic trash because they are negatively charged, and anionic trash inhibits the effects of various chemicals such as sizing agents. In addition, when anionic trash accumulates in the circulating water for papermaking, they form agglomerates, appearing as defects and defects in the paper, leading to a decrease in product yield, and even in the papermaking machine due to defects. Paper is generated and the operation rate is reduced. All of these factors increase the cost of paper manufacture. However, since paper breakage causes a significant decrease in productivity, suppression of paper breakage is an important issue at the paper manufacturing site.

  In order to overcome the above-mentioned problems, a chemical called a coagulant is used for the purpose of preventing anion trash from adsorbing to pulp fibers and preventing it from accumulating in papermaking circulating water. This coagulant is generally a cationic polymer (hereinafter referred to as a cationic polymer), and is a cationically modified polyacrylamide (hereinafter referred to as PAM) (for example, see Patent Document 1) or diallyldimethylammonium. Chloride (hereinafter referred to as DADMAC) (for example, refer to Patent Document 2), cation-modified polyamine salt (for example, refer to Patent Document 3), polyethyleneimine (hereinafter referred to as PEI) (for example, refer to Patent Document 4). However, adding too much to obtain a sufficient effect not only causes an increase in cost, but also inhibits the fixing of cationic papermaking chemicals added to the pulp slurry, The bad effect that the yield of will deteriorate. Therefore, it is preferable to exert a desired effect by adding as little a coagulant as possible.

JP 09-78487 A (2nd page) JP 05-263387 A (second page) JP 2004-175818 A (2nd page) JP 2000-511596 A (2nd page)

  An object of the present invention is to provide a material that efficiently binds so-called anionic trash contained in a papermaking raw material dispersion to pulp or the like by adding a small amount of a papermaking raw material treating agent. This makes it possible to suppress defects and defects that occur in the paper and paper breaks in the papermaking process.

  As a result of intensive studies on a cationic polymer to solve the above problems, the present inventor efficiently captures anion trash in a pulp slurry and binds it onto a pulp fiber. And the present invention has been completed.

The present invention includes the following contents.
(1) Structural formula (I) below:

（式中、Ｒ^１、Ｒ^２は、それぞれ互いに独立に、水素原子又は一価の有機基を表す。）
で表されるアミジニウム基を有する有機化合物であることを特徴とする製紙原料処理剤。
（２）下記構造式（ＩＩ）：

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group.)
A papermaking raw material treating agent, which is an organic compound having an amidinium group represented by the formula:
(2) Structural formula (II) below:

（式中、Ｒ^３、Ｒ^４は、それぞれ互いに独立に、水素原子又は一価の有機基を表す。）
で表されるベンズアミジニウム基を有する有機化合物である（１）項に記載の製紙原料処理剤。

(In the formula, R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group.)
The papermaking raw material treating agent according to item (1), which is an organic compound having a benzamidinium group represented by the formula:

  (3) Structural formula (III) below:

（式中、Ｒ^５、Ｒ^６は、それぞれ互いに独立に、水素原子又は一価の有機基を表し、Ｒ^７は単結合又は二価の有機基を表す。）
で表される有機化合物の単独重合体および／または重合活性な不飽和炭素−炭素結合を有する有機化合物との共重合体である（１）項に記載の製紙原料処理剤。

(In the formula, R ⁵ and R ⁶ each independently represent a hydrogen atom or a monovalent organic group, and R ⁷ represents a single bond or a divalent organic group.)
The papermaking raw material treating agent as described in the item (1), which is a homopolymer of an organic compound represented by formula (1) and / or a copolymer with an organic compound having a polymerization-active unsaturated carbon-carbon bond.

  The papermaking raw material treating agent of the present invention can efficiently bind so-called anionic trash contained in the papermaking raw material dispersion to pulp or the like by adding a small amount, and has an excellent effect in improving the yield of pulp fine fibers. Show.

  The present invention relates to a papermaking chemical that can efficiently capture anionic trash contained in a pulp slurry and can be supported on pulp fibers. The papermaking raw material treating agent of the present invention is contained in a pulp dispersion. Is added for the purpose of improving the yield of paper making chemicals and pulp fine fibers, and has an excellent effect. Details are described below.

In the papermaking raw material treating agent of the present invention, a compound having an amidinium group represented by the structural formula (I) is preferably used. In the structural formula (I), R ¹ and R ² represent a hydrogen atom or a monovalent organic residue, preferably a group selected from a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an aryl group. Specific examples include methyl group, ethyl group, allyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, n-hexyl group, benzene ring and the like. It is.

In addition, as the papermaking raw material treating agent of the present invention, a compound having a benzamidinium group represented by the structural formula (II) is more preferably used. In the structural formula (II), R ³ and R ⁴ represent a hydrogen atom or a monovalent organic residue, preferably a group selected from a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an aryl group. Specific examples include methyl group, ethyl group, allyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, n-hexyl group, benzene ring and the like. It is.

Furthermore, the compound containing an amidinium group used as the papermaking raw material treating agent of the present invention is more preferably a high molecular weight substance, and the compound represented by the structural formula (III) is active in polymerization with the amidinium group. A homopolymer of a compound having an unsaturated carbon bond or a copolymer with a compound having a polymerization active unsaturated carbon bond is preferred. In the structural formula (III), R ⁵ and R ⁶ represent a hydrogen atom or a monovalent organic residue, preferably a group selected from a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an aryl group. Specific examples include methyl group, ethyl group, allyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group, n-hexyl group, benzene ring and the like. Indicated. R ⁷ represents a single bond or a divalent organic residue, and is preferably a group selected from a benzene ring, a naphthalene ring and a heteroaromatic ring.

  Examples of the compound having a polymerization active unsaturated carbon bond used as a copolymerization component include ethylene, propylene, styrene, α-methylstyrene, vinyltoluene, vinyl acetate, allyl acetate, (meth) acrylic acid, methyl (meth) acrylate , Ethyl (meth) acrylate, benzyl (meth) acrylate, hydroxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxypolypropylene glycol (meth) acrylate , (Meth) acryloylmorpholine, (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diisopropyl (meth) acrylamide, acrylonitrile, N-vinylpyrrolidone, N-vinyl Formate, N-vinylacetate And compounds having a polymerization active unsaturated carbon-carbon bond such as N-vinyl-methyl carbamate, N-vinyl-ethyl carbamate, N-vinyl-phenyl carbamate, and the like. In addition, the ratio of the monomer having an amidinium group and the copolymerization component can be arbitrarily set as long as the desired performance is not impaired.

  The molecular weight of the high molecular weight material containing an amidinium group used as the papermaking raw material treating agent of the present invention is preferably 1,000 to 1,000,000, and more preferably 3,000 to 100,000.

In the compound having an amidinium group used as the papermaking raw material treating agent of the present invention, the counter anion is selected from inorganic anions such as halogen, sulfuric acid and perchloric acid, and organic anions such as sulfonic acid and carboxylic acid. Is not to be done. Further, the amidinium group represented by the structural formulas (I), (II), and (III) is usually accompanied by a counter anion, but there is no particular limitation on this, and an organic anion and an inorganic anion are not considered. Examples of the organic anion include carboxylic acids, sulfonic acids, and phosphonic acids represented by —COO ⁻ , —SO ₃ ^— , and —PO ₃ ^— . Examples of inorganic anions include halogen ions (Cl ⁻ , F ⁻ , Br ⁻ , I ⁻ ), nitrate ions, sulfate ions, hydrogen sulfate ions, phosphate ions, hydrogen phosphate ions, dihydrogen phosphate ions, tetrafluoro ions. Examples thereof include borate ions and hexafluorophosphate ions.

  Hereinafter, the present invention will be specifically described with reference to examples. Unless otherwise specified, “parts” and “%” represent “parts by mass” and “mass%”, respectively.

  The polymer material preferably used as the papermaking raw material treating agent of the present invention is a homopolymerization or copolymerization of a monomer having an amidinium group, or a homopolymerization of a monomer having a neutral amidine group that becomes a precursor of the amidinium group. Or obtained by protonation with a protonic acid such as hydrochloric acid after copolymerization. A monomer having an amidine group was synthesized with reference to DE 197 20 345 (A1), for example.

<Synthesis Example 1>
Synthesis example of N, N′-diethyl-4-vinylbenzamidine (monomer having an amidine group) 4-vinylbenzoyl chloride used as a starting material is described in Macromolecules, Vol. 22, no. 7, 1989.
Under an inert gas atmosphere, thionyl chloride (28 ml) and 4-tert-butylpyrocatechol (10 mg) were mixed and ice-cooled, and 4-vinylbenzoic acid (13.1 g, 88.5 mmol) was added little by little. After stirring for 4 hours, the temperature was raised to 40 ° C. and stirred for 1 hour. After returning to room temperature, the unreacted thionyl chloride was distilled off to obtain 13.3 g (79.9 mmol) of 4-vinylbenzoyl chloride as an intermediate. Obtained (90% yield for this step).

  Next, 4-vinylbenzoyl chloride (13.3 g, 79.9 mmol) was dissolved in anhydrous dichloromethane (50 mL) and cooled to −20 ° C., and a solution of ethylamine in dichloromethane (4 mol / L, 40 mL) was added dropwise thereto. . After stirring for 1 hour as it was, returning to room temperature and stirring for 15 hours, the by-product ethylamine hydrochloride was precipitated as a white solid. This was filtered off and the filtrate was concentrated to dryness, yielding 11.7 g (78.3 mmol) of intermediate N-ethyl-4-vinylbenzamide (98% yield for this step).

  Under an inert gas atmosphere, N-ethyl-4-vinylbenzamide (11.7 g, 78.3 mmol) and a solution of triethyloxonium tetrafluoroborate in dichloromethane (1 mol / L, 86 mL) were mixed and stirred at room temperature for 2 hours. Thereafter, phenothiazine (0.05 g) was added and stirred at room temperature for 41 hours. Further, absolute ethanol (180 ml) was added to the reaction solution, and an excess amount of ethylamine was blown into the reaction solution while cooling to 2 ° C., then the mixture was warmed to room temperature and stirred for 3 hours. Next, the reaction solution was concentrated under reduced pressure, and the resulting residue was dissolved in an aqueous sodium hydroxide solution (3 mol / L) while cooling with ice. Diethyl ether was added thereto for extraction, the organic layer was dried over sodium sulfate, the solvent was distilled off, and the residue was purified by sublimation. As a result, the target product, N, N′-diethyl-4-vinylamidine, became white needles. As a crystal, 12.0 g (59.5 mmol) was obtained. (The yield of this step is 76%). Melting point 76 ° C.

1H-NMR (in deuterated chloroform) results (numbers are in ppm):
δ 1.13 (s, 6H), 3.20 (s, 4H), 5.35 (d, 1H), 5.78 (d, 1H), 6.74 (q, 1H), 7.26 (d , 2H), 7.43 (d, 2H).

(Synthesis of polymer containing amidine structure)
Although the synthesis example of the high molecular weight body which has an amidinium group used as a papermaking raw material processing agent of this invention is shown below, a synthesis method is not limited to this.

<Synthesis Example 2>
Synthesis example of N, N′-diethyl-benzamidine hydrochloride homopolymer (P-1) 3 g (14.9 mmol) of N, N′-diethyl-4-vinylbenzamidine, 6N hydrochloric acid aqueous solution under an inert gas stream Dissolve 2.48 mL (14.9 mmol) in 20 mL of water, add 0.03 g of 2,2′-azobis (2-amidinopropane) dihydrochloride as an initiator, and stir at 60 ° C. for 5 hours. After returning the reaction liquid to room temperature, it was poured into tetrahydrofuran, and the viscous material that precipitated was separated by decantation. When the resulting viscous product was dried, N, N′-diethyl-benzamidine hydrochloride homopolymer (P-1), which was the target product, was obtained.
The molecular weight of this polymer was about 20,000 (in terms of polyethylene oxide).

<Synthesis Example 3>
Example of Synthesis of 1: 1 Copolymer of N, N′-Diethyl-Benzamidine Hydrochloride and Acrylamide (P-2) 3 g of N, N′-diethyl-4-vinylbenzamidine (14. 9 mmol), 2.48 mL (14.9 mmol) of 6N aqueous hydrochloric acid solution was dissolved in 17 ml of water and heated to 70 ° C. After adding 0.03 g of 2,2′-azobis (2-amidinopropane) dihydrochloride as a polymerization initiator, 0.34 g of 30% acrylamide aqueous solution was added dropwise over 30 minutes, and the mixture was further stirred at 70 ° C. for 3 hours. did. After cooling the reaction solution to room temperature, it was poured into tetrahydrofuran, and the viscous product precipitated was separated by decantation. When this viscous product was dried, the target copolymer (P-2) was quantitatively obtained.
The molecular weight of this copolymer was about 40,000 (in terms of polyethylene oxide).

<Synthesis Example 4>
Synthesis Example of 1: 9 Copolymer of Benzamidine and Acrylamide (P-3) 1 g (6.8 mmol) of 4-vinylbenzamidine and 4.4 g (61.2 mmol) of acrylamide were dissolved in absolute ethanol under an inert gas stream. Then, 0.05 g of azobisisobutyronitrile was added as a polymerization initiator, and the mixture was further stirred at 70 ° C. for 4 hours. Then, the reaction solution was returned to room temperature, and the precipitated crystals were collected by filtration. The union (P-3) was obtained quantitatively.
The molecular weight of this copolymer was about 10,000 (in terms of polyethylene oxide).
In addition, when using as a papermaking raw material processing agent of this invention, this crystal | crystallization is melt | dissolved in protonic acids, such as hydrochloric acid, and is cationized.

Example 1
Pulp slurry was prepared by the following operation, and the performance of the synthesized amidium compound as a papermaking raw material treating agent was evaluated.
600 ppm of the polymer P-1 (Synthesis Example 2) is added to about 3% by mass of deinked pulp (DIP) adjusted to a Canadian standard freeness of 220 mL (CSF), and stirred at 20 ° C. for 5 minutes. A slurry was created. This pulp slurry was filtered with a 100 mesh glass filter under reduced pressure, and the turbidity of the obtained filtrate was measured with a turbidimeter (manufactured by HACH, 2100P portable turbidimeter). Moreover, the pulp sheet formed by filtering under reduced pressure on a 200-mesh wire was dried, the absolute dry mass was measured, the residual rate of solid content was measured, and it showed in Table 1 with the result of the other Example.

Example 2
Performance evaluation was performed in the same manner as in Example 1. However, copolymer P-2 (Synthesis Example 3) was used as a papermaking raw material treating agent.

Example 3
Performance evaluation was performed in the same manner as in Example 1. However, copolymer P-3 (Synthesis Example 4) was used as a papermaking raw material treating agent.

Comparative Example 1
Performance evaluation was performed in the same manner as in Example 1. However, the papermaking raw material treating agent was not added.

Comparative Example 2
Performance evaluation was performed in the same manner as in Example 1. However, cation-modified polyacrylamide (PAM, molecular weight of about 300,000) was used as a papermaking raw material treating agent.

  As is clear from the comparison between Examples 1 to 3 and Comparative Examples 1 and 2, the papermaking raw material treating agent of the present invention exhibits a high effect in capturing anion trash.

The papermaking raw material treating agent of the present invention exhibits a high effect in capturing anion trash, and thereby it is possible to suppress defects and defects generated in the paper and paper breaks in the papermaking. Therefore, the papermaking raw material treating agent of the present invention has extremely high practical value.

Claims (3)

The following structural formula (I):

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group.)
A papermaking raw material treating agent, which is an organic compound having an amidinium group represented by the formula: The following structural formula (II):

(In the formula, R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group.)
The papermaking raw material treating agent of Claim 1 which is an organic compound which has the benzamidinium group represented by these. The following structural formula (III):

(In the formula, R ⁵ and R ⁶ each independently represent a hydrogen atom or a monovalent organic group, and R ⁷ represents a single bond or a divalent organic group.)
The papermaking raw material treating agent of Claim 1 which is a homopolymer of the organic compound represented by this, or a copolymer with the organic compound which has a polymerization active unsaturated carbon-carbon bond.