JPH0782692A - Slip-proof sizing agent for paper - Google Patents

Abstract

PURPOSE:To obtain the subject treating agent excellent in effect of preventing slip of paper surface and paper sizing property by subjecting a specific water- insoluble monomer to emulsion polymerization with a radical polymerization initiator using a specific cationic water-soluble polymer as a protective colloid. CONSTITUTION:(B) A water-insoluble monomer such as styrene or methyl methacrylate is subjected to emulsion polymerization with a radical polymerization initiator such as 2,2'-azobisamidinopropane hydrochloride using (A) at least one kind of cationic water-soluble polymer selected from A1: polyethyleneimine, etc.; A2: a polystyrene derivative obtained by replacing 40% (based on total styrene unit) of benzene ring by methyl group containing a quaternary ammonium salt and A3: a polymer obtained by (co)polymerizing monomer (s) selected from vinylamine, etc., allylamine, etc., and diallyldialkylammonium chloride as a protective colloid to provide the objective slip-proof sizing agent for paper used as emulsion. As the component A2, a polymer of formula I [(a)/(b)=(0-60)/(40-100) (molar ratio, a+b=100); (x) is chlorine, etc.] and/or formula II [(a)/(b)/(c)=(0-60)/(0-100)/(0-100) (molar ratio, a+b+c=100); (n) is 1-8; (x) is chlorine, etc.) is exemplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-slip agent and a sizing agent for paper.

[0002]

2. Description of the Related Art Anti-slip agents for paper are used, for example, by being applied to the surface of corrugated paper or paperboard to prevent slippage of the paper surface and to prevent paper products from becoming unloaded.
In many cases, it also has size performance. Conventionally, as a surface treating agent which imparts slip resistance to paper, a polymer obtained by reacting a quaternizing agent with a copolymer containing N, N-dialkylaminoalkyl (meth) acrylic acid ester as a constitutional unit is emulsified. Used as a dispersant, comprising a copolymer obtained by copolymerizing a (meth) acrylic acid ester with a bifunctional or trifunctional (meth) acrylic acid ester or (meth) acrylic acid (for example, Japanese Patent Application Laid-Open 62-
No. 133199), a product obtained by reacting a copolymer containing styrene and / or a styrene derivative and an N, N-dialkylaminoalkyl (meth) acrylic acid ester as a constituent unit with a quaternizing agent. (For example, JP-A-57-56598), a copolymer containing styrene and / or a styrene derivative and N, N-dialkylaminoalkyl (meth) acrylamide as a constitutional unit is reacted with a quaternizing agent. Consists of the obtained reaction product (for example, JP-A-2-26
No. 997) and the like are known.

[0003]

However, these anti-slip agents still have insufficient anti-slip properties and low size performance, so that higher performance is demanded. In addition, the emulsion dispersants described above have a low emulsifying effect, and when the polymerization concentration during emulsion polymerization is increased, aggregates are generated during polymerization, and therefore emulsion polymerization can be carried out only at a low concentration of 30% by weight or less. There was a problem that was low.

[0004]

[Means for Solving the Problems] The present inventors have arrived at the present invention as a result of extensive studies on a paper anti-slip agent and a sizing agent having a high concentration and a higher level of anti-slip properties and sizing properties.

That is, the present invention provides the following polymers (a1) to
Using at least one cationic water-soluble polymer (A) selected from (a3) as a protective colloid, the substantially water-insoluble ethylenic monomer (B) in an aqueous solvent,
It is an anti-slip agent for paper and a sizing agent, which comprises a polymer emulsion obtained by emulsion polymerization in the presence of a radical polymerization initiator (C). Polymer (a1): polyethyleneimine or a salt thereof. Polymer (a2): A polystyrene derivative in which at least 40% of all styrene units have benzene rings substituted with a methyl group containing a quaternary ammonium salt group. Polymer (a3): a polymer obtained by (co) polymerizing at least one monomer selected from vinylamine or a salt thereof, allylamine or a salt thereof, and diallyldialkylammonium halide.

Examples of the cationic water-soluble polymer (A) used in the present invention include polyethyleneimine and its inorganic acid or organic acid salt (a1); at least 40% of all styrene units have a benzene ring containing a quaternary ammonium salt group. A polystyrene derivative (a2) substituted with a methyl group containing;
Polymer (a3) obtained by (co) polymerizing at least one monomer selected from vinylamine, allylamine, inorganic acid or organic acid salt thereof and diallyldialkylammonium halide; and a mixture of two or more thereof. To be

The polyethyleneimine (a1) is a polymer obtained by ring-opening polymerization of ethyleneimine by a known method. The polyethyleneimine can be used as it is, but can also be used in the form of a salt in which some or all of the amino groups are neutralized with an acid. Examples of the acid used for neutralization include inorganic acids (hydrochloric acid, sulfuric acid, phosphoric acid, etc.) and organic acids (acetic acid, formic acid, propionic acid, etc.).

(A2) is, for example, a polymer obtained by the reaction of polystyrene whose benzene ring is chloromethylated by a conventional method and a tertiary amine. In (a2), it is preferable that at least 40%, preferably 50% or more of all styrene units of polystyrene have benzene rings substituted with a methyl group containing a quaternary ammonium salt group. Four
When the ratio of the benzene ring substituted with a methylene group containing a primary ammonium base is less than 40%, it cannot be used as a protective colloid because of its low solubility in water. The (a2)
Specific examples of include polymers represented by the following general formulas (1) and (2). [In the formula, a / b = 0 to 60/40 to 100 (molar ratio, but a + b = 100), and X represents Cl, Br, or I. ] [In the formula, a / b / c = 0 to 60/0 to 100/0 to 10
0 (molar ratio, but a + b + c = 100), n is 1 to 8
And X represents Cl, Br or I. ]

As the polymer (a3), at least one selected from vinylamine, allylamine, salts thereof and diallyldialkylammonium halide is used by a conventional method, for example, a known radical polymerization initiator under a nitrogen stream in an aqueous medium using a known radical polymerization initiator. It is a polymer obtained by polymerizing.
Examples of the acid forming a salt of vinylamine and allylamine include inorganic acids (hydrochloric acid, sulfuric acid, phosphoric acid, etc.) and organic acids (acetic acid, formic acid, propionic acid, etc.). Also,
The alkyl group and halogen group of the diallyldialkylammonium halide are not particularly limited, but diallyldimethylammonium chloride is particularly preferable.

The weight average molecular weight of (A) is usually 100
0-100,000, preferably 5,000-50,0
00. When the weight average molecular weight of (A) is less than 1000, it does not function as a protective colloid, and when it exceeds 100,000, the viscosity of the polymer emulsion obtained becomes extremely high, and it becomes difficult to coat it on paper.

Examples of the substantially water-insoluble ethylenic monomer (B) used in the present invention include vinyl monomers having a solubility in water at 25 ° C. of 10 g / dl or less. Specific examples of (B) include, for example, styrene,
Aromatic olefins such as α-methylstyrene; vinyl esters such as vinyl acetate; diolefins such as butadiene and isoprene; methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic such as butyl (meth) acrylate Acid esters; vinyl nitriles such as (meth) acrylonitrile; and mixtures of two or more thereof.

As (B), a crosslinkable monomer having two or more double bonds in the molecule can be used in combination. Specific examples of the crosslinkable monomer include ethylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, divinylbenzene, methylenebisacrylamide, trimethylolpropane tri (meth) acrylate, tetraallylethane and the like. These can be used as a mixture of two or more.

In the present invention, the amount of (A) when emulsion-polymerizing (B) is usually 0.5 to 30 relative to the weight of (B).
% By weight, preferably 0.5-5% by weight. When the amount of (A) is less than 0.5% by weight, the polymer emulsion obtained is unstable and easily separated, and when it exceeds 30% by weight, the anti-slip performance is deteriorated.

The radical polymerization initiator (C) used in the present invention includes the following compounds (c1) to (c5). (C1): 2,2′-azobisisobutyronitrile,
Oil-soluble azo compounds such as 2,2′-azobis (2,4-dimethylvaleronitrile. (C2): 2,2′-azobis (2-amidinopropane) or its hydrochloride, 4,4′-azobis (4 -Cyanovaleric acid) or an alkali metal salt thereof, 2,
2'-azobis [2- (2-imidazolin-2-yl)
Propane] or its hydrochloride, a water-soluble azo compound such as 2,2′-azobis [2-methyl-N- (2-hydroxyetol) propionamide]. (C3): Organic peroxide such as benzoyloxy peroxide and ditertiary butyl peroxide. (C4): Inorganic peroxide such as potassium persulfate, sodium persulfate and ammonium persulfate. (C5): (c4) and a reducing substance (sodium sulfite,
Redox initiator in combination with dimethylaminoethanol, dimethylaminobenzoic acid, etc.).

Of these, preferred is (c2), and particularly preferred are 2,2'-azobis (2-amidinopropane) hydrochloride and 2,2'-azobis [2- (2.
-Imidazolin-2-yl) propane] or its hydrochloride and 2,2'-azobis [2-methyl-N- (2
-Hydroxyetr) propionamide].
The amount of (C) used is usually 0.001-2 with respect to the amount of (B).
% By weight.

The water-based solvent used in the present invention mainly means water, and as the water, distilled water, ion-exchanged water, tap water, industrial water and the like are used as necessary. In addition to water, the water-based solvent may contain a water-soluble organic solvent such as lower alcohol, acetone, dioxane, ethylene glycol, and cellosolves.

When manufacturing the polymer emulsion of the present invention, other known additives may be optionally present. Other additives include, for example, a surfactant for assisting emulsification, a chain transfer agent for adjusting the molecular weight of the resulting polymer, and the like.

If desired, other known additives may be added to the polymer emulsion. Examples of the additives include stabilizers, thickeners, preservatives and the like.

The size of the micelle particles of the polymer emulsion is not particularly limited, but is usually 0.01 to 1 micron,
It is preferably 0.03 to 0.5 micron. If the size of the micelle particles is less than 0.01 micron, it does not show an emulsion state but becomes a solution state, the viscosity of the solution becomes very high, and it is not practical, and the slip resistance is not exhibited. On the other hand, 1
If it exceeds micron, the stability of the emulsion will be poor and separation will be easy.

The preferred method for polymerizing the polymer emulsion in the present invention is a method called soap-free emulsion polymerization which does not use a low molecular weight emulsifier. In this method, by balancing the hydrophilicity / hydrophobicity of the protective colloidal polymer (A) and the water-insoluble polymer (B) used, the polymer becomes fine particles in the aqueous solvent, and as a result, a stable polymer emulsion is obtained. To be

When emulsion polymerization is carried out in an aqueous solvent, the total weight of (A) and (B) in the polymerization system is usually 1 to 70% by weight, preferably 20 to 60% by weight, based on the whole polymerization system.

Examples of the method for producing the polymer emulsion include ordinary production methods such as a batch polymerization method, a continuous tube polymerization method and a semi-continuous polymerization method. As the polymerization method in the case of the batch type polymerization method,
(A), (B) and (C) are charged together into a reaction tank to carry out polymerization; (A), (B) and (C) are separately dropped and polymerized; (B) And a method of polymerizing the mixture of (C) and (C) while dropping them in water containing (A); however, the method is not particularly limited.

The polymerization temperature and time are selected depending on the polymerizability of the monomer, the decomposition temperature of the initiator, the half-life, etc.
The polymerization temperature is usually 30 to 130 ° C, preferably 50 ° C to 1
The temperature is 00 ° C., and the polymerization time is usually 1 to 10 hours.

[0024]

EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the examples and comparative examples, "part" means part by weight and "%" means% by weight.

Example 1 In a reaction vessel capable of heating, cooling, stirring and nitrogen aeration,
140 parts water, 4 parts polyethyleneimine with a molecular weight of about 10,000,
42 parts of methyl methacrylate and 18 parts of styrene were charged and stirred at 200 rpm. Next, 0.5 part of 2,2′-azobisamidinopropane hydrochloride was charged and the polymerization was carried out at 70 ° C. for 2 hours under a nitrogen stream while stirring. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state. After the completion of the polymerization, a uniform emulsion was obtained and the reaction rate was 99%. The pH of this emulsion was 8.5 and it was neutralized with sulfuric acid to pH 6.5. This emulsion was coated on a corrugated cardboard liner paper so that the coating amount was as shown in Table 1, and the performance was evaluated by the sliding angle and the degree of bump size. The evaluation results are shown in Table 1. The paper was coated by a method in which an emulsion diluted to a predetermined concentration was coated with a bar coater, and the coating was dried with a drum dryer at 100 ° C. for 60 seconds.

Example 2 In the same reaction vessel as in Example 1, 140 parts of water, trimethylamine of chloromethylated polystyrene and β-dimethylaminoethyltrimethylamine quaternary compound [styrene unit / chloromethylstyrene quaternary unit of trimethylamine / Chloromethylstyrene quaternary unit of β-dimethylaminoethyltrimethylamine = 40/30/30
(Mole ratio), molecular weight of about 20,000] 4 parts, methyl methacrylate 30 parts and styrene 30 parts were charged and stirred at 200 rpm. Next, 0.5 part of 2,2′-azobisamidinopropane hydrochloride was charged and stirred under a nitrogen stream at 70 ° C.
Was polymerized for 2 hours. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state. After the completion of the polymerization, a uniform emulsion was obtained and the reaction rate was 99%. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 3 The same reaction vessel as in Example 1 was charged with 140 parts of water and a molecular weight of about 1
4 parts of polyallylamine hydrochloride and 60 parts of methyl methacrylate were charged and stirred at 200 rpm. Next, 0.5 parts of 2,2′-azobis [2-methyl-N- (2-hydroxyetol) propionamide] was charged and the polymerization was carried out at 70 ° C. for 2 hours under a nitrogen stream while stirring. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state.
After the polymerization was completed, a uniform emulsion was obtained and the reaction rate was 99.
%Met. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 4 The same reaction vessel as in Example 1 was charged with 140 parts of water and a molecular weight of about 1
10,000 parts of polyethyleneimine, 30 parts of methyl methacrylate
Parts, 30 parts of styrene and 0.06 part of divinylbenzene were charged and stirred at 200 rpm. Next, 0.5 part of 2,2′-azobisamidinopropane hydrochloride was charged and the polymerization was carried out at 70 ° C. for 2 hours under a nitrogen stream while stirring. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state.
After the polymerization was completed, a uniform emulsion was obtained and the reaction rate was 99.
%Met. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 5 In a reaction vessel similar to that of Example 1, 140 parts of water, trimethylamine quaternary product of chloromethylated polystyrene [styrene unit / chloromethylstyrene quaternary unit of trimethylamine = 40/60 (molar ratio) , Molecular weight of about 20,000] 6
Parts, 37.8 parts methyl methacrylate and 1 styrene
6.2 parts were charged and stirred at 200 rpm. Next 2,
0.12 parts of 2'-azobisamidinopropane hydrochloride was charged and the polymerization was carried out at 70 ° C for 2 hours under a nitrogen stream while stirring. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state. After the completion of the polymerization, a uniform emulsion was obtained, and the polymerization rate was 99.9%. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 6 140 parts of water and trimethylamine quaternary product of chloromethylated polystyrene [styrene unit / chloromethylstyrene quaternary unit of trimethylamine = 40/60 (molar ratio) were placed in the same reaction vessel as in Example 1. , Molecular weight of about 20,000] 4
Parts, 39.2 parts of methyl methacrylate and 1 of styrene
6.8 parts were charged and stirred at 200 rpm. Next 2,
0.2 parts of 2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] was charged and the polymerization was carried out at 80 ° C for 2 hours under a nitrogen stream while stirring. Along with the polymerization, the polymerization system gradually became cloudy and became an emulsified state. After the completion of the polymerization, a uniform emulsion was obtained and the reaction rate was 99.8.
%Met. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 7 In the same reactor as in Example 1, 140 parts of water, trimethylamine quaternary product of chloromethylated polystyrene [styrene unit / chloromethylstyrene quaternary unit of trimethylamine = 40/60 (molar ratio) , Molecular weight of about 20,000] 2 parts,
34 parts of methyl methacrylate, 17 parts of styrene, and 9 parts of vinyl acetate were charged, and the same operation as in Example 1 was performed thereafter. After the completion of the polymerization, a uniform emulsion was obtained and the reaction rate was 99.8%. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Example 8 In the same reactor as in Example 1, 140 parts of water, trimethylamine quaternary product of chloromethylated polystyrene [styrene unit / chloromethylstyrene quaternary unit of trimethylamine = 40/60 (molar ratio) , Molecular weight of about 20,000] 2 parts,
58 parts of styrene and 0.06 part of divinylbenzene were charged, and the same operation as in Example 1 was performed thereafter. After the polymerization was completed, a uniform emulsion was obtained, and the reaction rate was 99.4%. This emulsion was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 1.

Comparative Example 1 A commercially available anti-corrugation agent for corrugated board (poly-styrene / acrylic acid ester type solution type, anion type) was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 2 A commercially available anti-corrugation agent for corrugated board (polystyrene emulsion type, cationic type) was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

Comparative Example 3 In a reaction vessel similar to that of Example 1, 140 parts of water, trimethylamine quaternary product of chloromethylated polystyrene [styrene unit / chloromethylstyrene quaternary unit of trimethylamine = 40/60 (molar ratio) , Molecular weight of about 20,000] 18
Parts, 29.4 parts methyl methacrylate and 1 styrene
2.6 parts were charged and stirred at 200 rpm. Next 2,
0.12 parts of 2'-azobisamidinopropane hydrochloride was charged and the polymerization was carried out at 70 ° C for 2 hours under a nitrogen stream while stirring. With the polymerization, the polymerization system gradually became a hazy emulsified state. A transparent solution was obtained in the latter half of the polymerization, and the reaction rate was 99.0%. The pH of this emulsion is 5.
The average particle size was too small to be measured.
This solution was evaluated in the same manner as in Example 1. The evaluation results are shown in Table 2.

[0036]

[Table 1] Note 1: Measured according to the tilt method of JIS P-8147 (the larger the value, the better the slip resistance). Note 2: Measured according to JIS P-8140 (the smaller the value, the better the size).

[0037]

[Table 2]

[0038]

The anti-slip agent / size for paper of the present invention has the following effects. (1) It is more effective than the conventional one in preventing slippage on the paper surface,
It has a great effect to prevent the paper products from falling apart. (2) The paper size is better than the conventional one, and the effect of suppressing the decrease in paper strength due to absorption of water is excellent. (3) The emulsion concentration is higher than that of the conventional one. Since the above-mentioned effects are exhibited, the paper anti-slip agent / size agent of the present invention is extremely useful as an anti-slip agent / size agent for cardboard paper, paperboard and the like.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C09D 139/00 PGL 179/02 PLU C08F 212/14 MJY

Claims (5)

[Claims] 1. At least one cationic water-soluble polymer (A) selected from the following polymers (a1) to (a3) is used as a protective colloid, and a substantially water-insoluble ethylenic monomer (B) is used. A paper anti-slip agent and sizing agent comprising a polymer emulsion obtained by emulsion polymerization in an aqueous solvent in the presence of a radical polymerization initiator (C). Polymer (a1): polyethyleneimine or a salt thereof. Polymer (a2): A polystyrene derivative in which at least 40% of all styrene units have benzene rings substituted with a methyl group containing a quaternary ammonium salt group. Polymer (a3): a polymer obtained by (co) polymerizing at least one monomer selected from vinylamine or a salt thereof, allylamine or a salt thereof, and diallyldialkylammonium halide. 2. A polymer (a2) represented by the following general formula (1) and / or general formula (2):
Anti-slip agent and sizing agent described. [In the formula, a / b = 0 to 60/40 to 100 (molar ratio, but a + b = 100), and X represents Cl, Br, or I. ] [In the formula, a / b / c = 0 to 60/0 to 100/0 to 10
0 (molar ratio, but a + b + c = 100), n is 1 to 8
And X represents Cl, Br or I. ] 3. The weight average molecular weight of (A) is from 5,000 to.
The anti-slip agent / size agent according to claim 1 or 2, which is 100,000. 4. The amount of (A) is based on the weight of (B).
It is 5 to 30% by weight, and the anti-slip agent and sizing agent according to any one of claims 1 to 3. 5. A radically polymerizable initiator (C) in the molecule,
An azo radical polymerization initiator containing an acid-neutralized amino group, amide group or imidazoline group.
4. The anti-slip agent and sizing agent according to any one of to 4.