JP2003155688A - Method for pretreating papermaking raw material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for pretreating a papermaking raw material by which an amphoteric water-soluble polymer efficiently adsorbs on pitch particles to prevent fouling of paper caused by the pitch even when mechanical pulp or waste paper is compounded with the papermaking raw material. SOLUTION: The amphoteric water-soluble polymer composed of 5-95 mol% of two kinds selected from specific catonic monomers, 5-50 mol% of an anionic monomer and 0-90 mol% of a nonionic monomer is added into the papermaking raw material before papermaking to treat the papermaking raw material. A sheet of paper is then formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pretreatment method for a papermaking raw material, and more specifically, an amphoteric water-soluble polymer having a specific composition is added to a papermaking raw material before papermaking, and then treated. Regarding the pretreatment method.

[0002]

2. Description of the Related Art So-called pitch in a papermaking process is a substance which is insoluble in water and has an adhesive property. The pitch includes those derived from wood, latex used in the paper manufacturing process, and others. From wood, fats, fatty acids,
It contains terpenes, steroids, natural resins and gums, which remain after pulping. In the later papermaking process, these adhesive substances are released,
Although dispersed in a colloidal state, the colloidal state is destroyed by strong shearing force, abrupt pH change, addition of a sulfuric acid band, and the like, resulting in aggregation and coarsening, resulting in a so-called pitch. On the other hand, the pitch derived from the paper-processing substance has the same colloidal state as the colloidal state is destroyed while the latex such as the coat block in the coat paper manufacturing process is recycled at the wet end. Coagulation with calcium carbonate causes coarsening, and a white pitch deposit is formed on the synthetic paper after paper making, causing troubles. In a factory that produces coated base paper, calcium carbonate in the coat block constitutes a large part of the ash content in the papermaking, and
In some cases tobrok is the only source of filler.
The ash content in the coat block is more difficult to apply than the usual internal fillers. That is, the filler yield rate becomes low. This is because the pigment particle size of the coating grade is generally smaller than the internal addition particle size. Therefore, if the raw material yield rate is lowered, the concentration of white water circulating in the papermaking system is increased to cause filler stains. In addition, the sizing agent that does not fix is hydrolyzed in the papermaking process and causes stains (pitch troubles).

JP-A-4-241184 discloses a dimethyldiallylammonium chloride / acrylic acid / (copolymerizing alkyl acrylates in some cases) copolymer for the wet end of a papermaking system for suppressing natural pitch troubles. A method of adding is disclosed. Further, in the bleaching step alkali extraction of pulp production, as a method of removing pitch in pulp derived from raw wood, a copolymer of a water-soluble unsaturated carboxylic acid and a hydrophobic monomer, pulp pulp after bleaching -Added before entering the next alkali extraction column (JP-A-11-25649).
0). Furthermore, as a method for preventing troubles caused by various pitches derived from wood or waste paper, polystyrene sulfonic acid (salt) or polyisoprene sulfonic acid (salt) is dissolved in shower water at a place where the pitch easily attaches, It is described that it is supplied by a shower, an injection nozzle, a water doctor, or the like (Japanese Patent Laid-Open No. 11-18998).
7). In addition, as an example of using a cationic polymer, a method of dissolving a vinyl imidazoline polymer in papermaking machine washing water and adding it is described in JP-A No. 11-930911 as a general method for preventing problems with pitch substances. .

[0004]

However, with respect to the stain prevention method, a decisively effective countermeasure plan has not been proposed yet. In particular, there is no disclosure of a method for preventing the occurrence of defects in the paper by pretreatment with an amphoteric water-soluble polymer obtained by copolymerizing two kinds of cationic monomers. An object of the present invention is to develop a pretreatment method of a papermaking raw material for preventing paper stain due to pitch when mechanical pulp or waste paper is mixed with the papermaking raw material.

[0005]

According to the invention of claim 1, 5 to 95 mol% of two kinds selected from the cationic monomers represented by the following general formulas (1) to (3), After the amphoteric water-soluble polymer consisting of 5 to 50 mol% of the anionic monomer represented by the formula (4) and 0 to 90 of the nonionic monomer is added to the papermaking raw material before papermaking and treated, It is a pretreatment method for a papermaking raw material, which is characterized by making paper.

[Chemical 1] General formula (1)

[Chemical 2] General formula (2)

[Chemical 3] General formula (3) R1, R2 and R3 are alkyl or alkoxyl groups having 1 to 3 carbon atoms, R4, R5 and R6 are alkyl or alkoxyl groups having 1 to 3 carbon atoms, R7 is hydrogen or methyl group, R8 and R9 are An alkyl or alkoxyl group having 1 to 3 carbon atoms, R10 is a benzyl group, A is oxygen or NH, B is an alkylene group or alkoxylene group having 2 to 4 carbon atoms, X1, X2 and X3 are anions. Represent each.

[Chemical 4] General formula (4) R11 is hydrogen, a methyl group or a carboxymethyl group, A
Is SO3, C6H4SO3, CONHC (CH3) 2C
H2SO3, C6H4COO or COO, R12 represents hydrogen or COOY2, Y1 or Y2 represents hydrogen or a cation, respectively.

According to a second aspect of the present invention, the amphoteric water-soluble polymer is represented by the above general formulas (1) to (3) by allowing a polymer dispersant soluble in the salt aqueous solution to coexist in the salt aqueous solution. 5 to 95 mol% of two kinds selected from cationic monomers, and 5 to 50 mol% of anionic monomers represented by the following general formula (4).
And a dispersion of a fine particle having a particle diameter of 100 μm or less, which is produced by dispersion-polymerizing a monomer mixture including the nonionic monomer 0 to 90 under stirring. It is the method for pretreatment of the raw material for papermaking described.

According to a third aspect of the present invention, the polymer dispersant is
The method for pretreatment of a papermaking raw material according to claim 2, wherein the pretreatment is for ionicity.

A fourth aspect of the present invention is the pretreatment method for a papermaking raw material according to the second aspect, wherein the salt constituting the aqueous salt solution contains at least one polyvalent anion salt.

According to a fifth aspect of the invention, the amphoteric water-soluble polymer contains 5 to 95 mol% of two kinds selected from the cationic monomers represented by the general formulas (1) to (3). A liquid containing an oil-soluble emulsifier as a discontinuous phase of an aqueous solution of a monomer mixture consisting of 5 to 50 mol% of anionic monomers represented by the following general formula (4) and 0 to 90 of nonionic monomers. The pretreatment method for a papermaking raw material according to claim 1, which comprises a dispersion liquid produced by forming a water-in-oil emulsion having a hydrocarbon as a continuous phase and emulsion-polymerizing it with stirring.

When the number of moles of the total amount of the cationic monomers in the monomer mixture is represented by C and the number of moles of the anionic monomer is represented by A, C and A are The pretreatment method for a papermaking raw material according to claim 2 or 5, which has the following relationship. 1.0 ≦ C / A ≦ 6.0

The invention of claim 7 is based on the general formula (1) to
The cationic monomers represented by (3) are methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride and acryloyloxyethylbenzyldimethylammonium chloride, and the anionic monomer is (meth) ) A method for pretreatment of a raw material for papermaking according to claim 1, wherein acrylic acid is used and the nonionic monomer is (meth) acrylamide.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The amphoteric water-soluble polymer used in the present invention comprises two kinds of cationic monomers represented by the above-mentioned general formulas (1) to (3). ~ 95 mol%, anionic monomer 5 represented by the general formula (4)
50 mol% and 0 to 90 nonionic monomers. In a general synthesis method, these monomers are dissolved and mixed in an aqueous medium, the pH of the aqueous solution is adjusted to 2 to 5, and then a polymerization initiator is added in a nitrogen atmosphere to perform copolymerization. As the polymerization method, aqueous solution polymerization, water-in-oil polymerization, water-in-oil dispersion polymerization, dispersion polymerization in salt solution, or the like can be used.

Among the cationic monomers used, the monomer represented by the general formula (1) is a quaternary ammonium salt of a monohalide of dialkylaminoalkyl methacrylate. Examples thereof include methacryloyloxyethyltrimethylammonium chloride, methacryloyloxy 2-hydroxypropyltrimethylammonium chloride, methacryloylaminopropyltrimethylammonium chloride, and the like.

The cationic monomer represented by the general formula (2) is a quaternary ammonium salt of dialkylaminoalkyl acrylate monohalide. Examples thereof include acryloyloxyethyltrimethylammonium chloride, acryloyloxy 2-hydroxypropyltrimethylammonium chloride, acryloylaminopropyltrimethylammonium chloride and the like.

The cationic monomer represented by the general formula (3) is a quaternary ammonium salt of a dihalogenated monoalkyl halide of dialkylaminoalkyl (meth) acrylate. Examples thereof include (meth) acryloyloxy 2-hydroxypropyldimethylbenzylammonium chloride, (meth) acryloylaminopropyldimethylbenzylammonium chloride or (meth) acryloyloxyethyldimethylbenzylammonium chloride.

Further, as an example of the anionic monomer represented by the general formula (4), a sulfone group or a carboxyl group may be used, and both may be used in combination. Examples of the sulfonic group-containing monomer are vinyl sulfonic acid, vinyl benzene sulfonic acid, 2-acrylamido 2-methylpropane sulfonic acid, and the like. Examples of the carboxyl group-containing monomer are methacrylic acid, acrylic acid, itaconic acid, maleic acid, p-carboxystyrene and the like.

When polymerizing a nonionic water-soluble polymer, it is most preferable to use acrylamide,
A nonionic monomer other than acrylamide may be copolymerized. As such examples, N, N-dimethylacrylamide, vinyl acetate, acrylonitrile, methyl acrylate, 2-hydroxyethyl (meth) acrylate, diacetone acrylamide, N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, Examples include acryloylmorpholine.

The most preferable combination of these monomers is methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, acrylic acid and acrylamide or methacryloyloxyethyltrimethylammonium chloride, acryloyloxy. Examples are ethylbenzyldimethylammonium chloride, acrylic acid and acrylamide, or acryloyloxyethyltrimethylammonium chloride, acryloyloxyethylbenzyldimethylammonium chloride, acrylic acid and acrylamide.

The molar ratio of the cationic monomer in the amphoteric water-soluble polymer used in the present invention is 5 to 95 mol%, preferably 10 to 90 mol%, more preferably 2
It is 0 to 80 mol%. The molar ratio of the anionic monomer is
5 to 50 mol% is preferable, and more preferably 10 to 5
It is 0 mol%. The molar ratio of the nonionic monomer is 0 to
It is 90 mol%, preferably 0 to 80 mol%.
The molecular weight of these amphoteric water-soluble polymers is 50,000 to 10
It is, 000,000, preferably 100,000 to 5,000,000.

Further, polyfunctional monomers such as N, N-methylenebisacrylamide and ethylene glycol (meth) acrylate, or N, N-dimethyl (meth) acrylamide and N, N-diethyl (meth) ) It is also possible to copolymerize a thermally crosslinkable monomer such as acrylamide to synthesize a crosslinked or branched polymer and modify it.

The polymerization conditions are usually determined appropriately depending on the monomers used and the mole% of copolymerization, and the temperature is 0-10.
Perform in the range of 0 ° C. A radical polymerization initiator is used to initiate the polymerization. These initiators may be either oil-soluble or water-soluble, and can be polymerized by any of azo type, peroxide type and redox type. Examples of oil-soluble azo initiators include 2,2′-azobisisobutyronitrile,
1,1'-azobis (cyclohexanecarbonitrile), 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2-methylpropione-
G), 4,4-azobis (4-methoxy-2,4dimethyl) valeronitrile, etc., which are dissolved in a water-miscible solvent and added.

Examples of water-soluble azo initiators include:
2'-azobis (amidinopropane) dihydrochloride,
2,2'-Azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 4,4 '
-Azobis (4-cyanovaleric acid) and the like. Further, examples of the redox system include a combination of ammonium peroxodisulfate and sodium sulfite, sodium hydrogen sulfite, trimethylamine, tetramethylethylenediamine and the like. Further examples of peroxides include ammonium or potassium peroxodisulfate,
Examples thereof include hydrogen peroxide, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, succinic peroxide, t-butylperoxy 2-ethylhexanoate and the like. Most preferred of these initiators are water-soluble azo initiators2,
2'-azobis (amidinopropane) dihydrochloride,
2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride.

The amphoteric water-soluble polymer used in the present invention can be applied in any form, but the most preferable product form is a water-in-oil type emulsion polymerized product or a salt aqueous solution dispersed polymerized product. The main reason for this is that the concentration can be increased as compared with the aqueous polymer product and the dissolution time can be shortened as compared with the powder product. Further, when a dispersion polymerized product in a salt aqueous solution is dissolved in water, the aqueous solution viscosity is lower than that of the aqueous solution product and the powder product, and the dispersibility in white papermaking water is good.

The water-soluble polymer comprising a fine polymer particle dispersion liquid dispersed in an aqueous salt solution can be manufactured based on JP-A-62-15251. That is,
It is composed of a dispersion liquid of polymer fine particles having a particle size of 100 mμ or less, which is produced by stirring in the presence of a polymer soluble in a salt aqueous solution. Although nonionic or ionic can be used, an ionic polymer is more preferable. In the case of nonionic, it is a completely amidated product of a styrene / maleic anhydride copolymer or a butene / maleic anhydride copolymer. As the ionic polymer, a homopolymer of a cationic monomer such as dimethyldiallylammonium chloride or (meth) acryloyloxyethyltrimethylammonium chloride or a copolymer with a nonionic monomer is used.

The molecular weight of the ionic polymer is as follows:
It is 5,000 to 3 million, preferably 50,000 to 1.5 million. Further, as the molecular weight of the nonionic polymer component,
1,000 to 1,000,000, preferably 1,000 to
It is 500,000. As the addition amount of these polymer dispersants,
It is 1/100 to 1/10, preferably 2/100 to 8/100 with respect to the monomer.

As the inorganic salts constituting the aqueous salt solution, polyvalent anion salts are more preferable, and sulfates or phosphates are suitable, and specifically, ammonium sulfate, sodium sulfate, magnesium sulfate, aluminum sulfate, ammonium hydrogenphosphate. , Sodium hydrogenphosphate, potassium hydrogenphosphate and the like can be exemplified, and it is preferable to use these salts as an aqueous solution having a concentration of 15% or more.

The emulsion polymerized product is a water-in-oil emulsion in which the aqueous solution of the monomer mixture is used as the discontinuous phase and the liquid hydrocarbon containing the oil-soluble emulsifier is used as the continuous phase, and emulsion polymerization is carried out with stirring. It can be manufactured by

Examples of the liquid hydrocarbon used as the dispersion medium are paraffins or mineral oils such as kerosene, light oil, and middle oil, or hydrocarbon synthetic oil having characteristics such as boiling point and viscosity in the substantially same range as these. Or a mixture of these.

Examples of oil-soluble emulsifiers having HLB and an effective amount to form a water-in-oil emulsion include HLB
It is a 3 to 11 emulsifier, and its nonionic property is more preferable.
Specific examples thereof include sorbitan monooleate, sorbitan monostearate, sorbitan monopalmitate and the like. The amount of these surfactants added is
0.5 to 10% by weight based on the total amount of water-in-oil emulsion
And preferably 1 to 5% by weight.

The ionic group in the amphoteric water-soluble polymer used in the present invention exerts a particular effect by adjusting the balance thereof. That is, 2 to 5 mol% selected from cationic monomers, 5 to 50 mol% anionic monomers
It is a case where the following conditions are further satisfied in the range consisting of mol% and the nonionic monomer 0 to 90. That is,
When the total number of cationic monomers in the amphoteric water-soluble polymer is represented by C and the total number of anionic monomers is represented by A, 1.0 ≦ C / A ≦ 6.0 Represents that the number of moles of the cationic monomer is equivalent to 6 times the number of moles of the anionic monomer. Generally, the amphoteric water-soluble polymer is polymerized by adjusting the pH to 2 to 5 during the polymerization. The pH of the diluted solution added to the water to be treated is also considered. When it is added to the water to be treated having a pH of about 5 to 8, ion complex is generated and various effects such as an increase in apparent molecular weight are exhibited. When the ratio is in the above range, the ion complex is most easily generated, and it is preferable as the amphoteric water-soluble polymer. Occasionally, since the cationic monomer is excessive, it is cationic as a whole, and when used in combination with an anionic water-soluble polymer, an excellent effect is exhibited.

The amphoteric water-soluble polymer of the present invention contains a methacrylic acid quaternary ammonium salt group-containing monomer and an acrylate type quaternary ammonium salt group as shown by the general formulas (1) and (2). Since two kinds selected from the monomer or the quaternary ammonium salt group-containing monomer having a benzyl group are contained at the same time, a unique effect is exhibited. That is, since a methyl group is bonded to the α-carbon of the methacrylic acid, it is difficult to obtain a highly polymerized product with low reactivity as compared with the acrylate, but hydrolysis resistance is present. Since it is not bonded, a branched structure is unlikely to occur, and as a result, insolubilization of the polymer due to cross-linking is unlikely to occur, and it has an appropriate hydrophobicity. On the contrary, acrylate has strong hydrophilicity, but it has high reactivity and is easy to produce a polymer. On the other hand, since the quaternary ammonium salt group-containing monomer having a benzyl group has a hydrophobic group, it is easily adsorbed on lipophilic pitch particles. Therefore, the amphoteric water-soluble polymer of the present invention has an advantage that it is efficiently adsorbed on lipophilic pitch particles due to the balance between hydrophobicity and hydrophilicity, and the treatment effect is enhanced.

The amount of the amphoteric water-soluble polymer used in the present invention added to the papermaking raw material varies depending on the cation requirement of the papermaking raw material, but is about 100 to 3000 ppm as the polymer content per dry papermaking raw material. , Preferably 2
0 to 1500 ppm, most preferably 200 to
It is 1000 ppm. The amount of amphoteric water-soluble polymer added is
The cation required amount of the papermaking raw material is measured and determined using a PCD-03 type manufactured by Mutec. For example, after adding the polymer of the present invention to the used paper-making raw material and stirring the mixture, Whatman filter paper NO. The raw material is filtered by 41, and the cation required amount and turbidity of the filtrate are measured. The place where the turbidity is the lowest is estimated to be a guideline for the proper addition amount, but it cannot be accurately determined unless it is applied to the paper manufacturing site.

The amphoteric water-soluble polymer used in the present invention is more preferably a polymer having a quaternary ammonium salt group in its molecule. It is presumed that the reason for this is that the dirt component such as pitch has a strong adsorption force and that the pitch component is agglomerated to prevent the occurrence of defects on the paper. Further, as a more preferable product form of the cationic water-soluble polymer,
A dispersion-polymerized product in an aqueous salt solution is raised. The reason for this is that when a dispersion polymerized product in a salt aqueous solution is dissolved in water, the aqueous solution viscosity is lower than that of an aqueous solution product, a powder product or a water-in-oil type emulsion polymerized product, and the dispersion composition to the paper-making raw material is good. Adsorption is also efficient and the effect is higher than other polymer products.

As a place of addition, it is more effective to add the pulp directly to the raw material pulp which causes the most stain than to use a mixing chest in which various pulps are mixed.
Also, it is more effective to add before diluting with white water. Therefore, examples of the adding place include the raw material pulp chest piping outlet for the purpose of treatment, or the front of the fan pump diluted with white water.

The paper stain prevention method of the present invention simultaneously improves the yield rate on the wire. That is,
Pile or anionic substance is contained in the flyer waste paper that is the target of the stain prevention treatment. Therefore, before the addition of the amphoteric water-soluble polymer of the present invention, even if the cationic retention agent is added, it is consumed by the anionic substance and pitch, and the effect of the retention agent cannot be exhibited. As a result, the wire
The conventional situation is that the yield above is low. However, the formulation of the present invention neutralizes the zeta potential on the surface of the pitch substance to a certain extent and neutralizes the anion component in the raw material, so that the retention rate is improved. .

[0036]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples unless it exceeds the gist.

(Synthesis Example 1) A five-necked separable flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube was used.
Ion-exchanged water (185.7 g) and 60% aqueous solution of acrylic acid (16.3 g) were charged, and 30% aqueous solution of sodium hydroxide (16.3 g) (based on acrylic acid of 90 equivalent%) was added thereto for neutralization. Then, as a dispersant, acryloyloxyethyl trimethyl ammonium chloride homopolymer (20%
Aqueous solution, molecular weight 1.2 million, 30 g (to monomer 6.0)
%), Ammonium sulfate 125.0 g, acrylamide 50% aqueous solution 19.2 g, acryloyloxyethyltrimethylammonium chloride, 80% aqueous solution 65.6 g.
Then, methacryloyloxyethyltrimethylammonium chloride and 35.2 g of an 80% aqueous solution were charged and completely dissolved. Further, 0.2 g of isopropyl alcohol was added as a polymerization degree control agent. After maintaining the internal temperature at 33 to 35 ° C. and substituting with nitrogen for 30 minutes, 1% of 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride was used as an initiator. Aqueous solution 4.0g
(0.1% of monomer) was added to initiate polymerization. 2.5 hours after the start, a slight increase in the viscosity of the reaction product was observed, and 2
The state continued for 5 minutes, but immediately after that, it was settled and transferred to the dispersion liquid. 8 hours after the start, the initiator solution was added to 1.0
g was added, and polymerization was further performed for 8 hours. The obtained dispersion has a swelling monomer concentration of 20% and a polymer particle size of 10%.
The dispersion liquid had a viscosity of 510 mPa · s or less.
In addition, a molecular weight measuring device by a static light scattering method (Otsuka Electronics D
The weight average molecular weight was measured by LS-7000).
This sample is referred to as prototype-1. The results are shown in Table 2.

(Synthesis Example 2) A five-necked separable flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube was used.
Ion-exchanged water (185.0 g) and a 60% aqueous solution of acrylic acid (15.4 g) were charged, and 30% aqueous solution of sodium hydroxide (15.4 g) (based on acrylic acid: 90 equivalent%) was added to neutralize. Then, as a dispersant, acryloyloxyethyl trimethyl ammonium chloride homopolymer (20%
Aqueous solution, molecular weight 1.2 million, 30 g (to monomer 6.0)
%), Ammonium sulfate 125.0 g, acrylamide 50% aqueous solution 18.2 g, acryloyloxyethyltrimethylammonium chloride, 80% aqueous solution 62.1 g.
Then, acryloyloxyethylbenzyldimethylammonium chloride and 39.9 g of an 80% aqueous solution were charged and completely dissolved. Further, 0.2 g of isopropyl alcohol was added as a polymerization degree control agent. Internal temperature 33-35 ℃
And nitrogen purge for 30 minutes, then 2,2'-as an initiator
Azobis [2- (5-methyl-2-imidazoline-2-
Ile) propane] 4.0 g of 1% aqueous solution of dihydrochloride
(0.1% of monomer) was added to initiate polymerization. 2.5 hours after the start, a slight increase in the viscosity of the reaction product was observed, and 1
The state continued for 5 minutes, but immediately after that, it was settled and transferred to the dispersion liquid. 8 hours after the start, the initiator solution was added to 1.0
g was added, and polymerization was further performed for 8 hours. The obtained dispersion has a swelling monomer concentration of 20% and a polymer particle size of 10%.
The viscosity of the dispersion was 450 mPa · s or less.
In addition, a molecular weight measuring device by a static light scattering method (Otsuka Electronics D
The weight average molecular weight was measured by LS-7000).
This sample is referred to as prototype-2. The results are shown in Table 2.

(Synthesis Example 3) A five-necked separable flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube was used.
1605.0 g of ion-exchanged water and 15.4 g of 60% aqueous solution acrylic acid were charged, and 14.2 g of sodium hydroxide of 30% aqueous solution (90 equivalent% of acrylic acid) was added thereto for neutralization. Then, as a dispersant, acryloyloxyethyltrimethylammonium chloride homopolymer (20
% Aqueous solution, molecular weight 1.2 million), 27.5 g (5.5% of monomer), ammonium sulfate 125.0 g, acrylamide 50% aqueous solution 16.8 g, methacryloyloxyethyltrimethylammonium chloride, 80% aqueous solution 3
8.3 g, acryloyloxyethylbenzyldimethylammonium chloride, and 73.3 g of an 80% aqueous solution were charged and completely dissolved. Further, 0.2 g of isopropyl alcohol was added as a polymerization degree control agent. Inside temperature 33
After maintaining at ˜35 ° C. and purging with nitrogen for 30 minutes, 2.0 g of a 1% aqueous solution of 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride as an initiator. (0.05% of monomer) was added to initiate polymerization. 2.5 hours after the start of the reaction, a slight increase in the viscosity of the reaction product was observed, and the state was maintained for 30 minutes, but immediately after that, the reaction product stopped and transferred to the dispersion liquid. After 8 hours from the start, 1.0 g of the above-mentioned initiator solution was added, and polymerization was further performed for 8 hours. The concentration of the swelling monomer in the obtained dispersion was 20%, the particle size of the polymer was 10 μm or less, and the viscosity of the dispersion was 600 mPa · s.
Met. Moreover, the weight average molecular weight was measured by a molecular weight measuring device (DLS-7000 manufactured by Otsuka Electronics) by the static light scattering method. This sample is referred to as prototype-3. The results are shown in Table 2.

(Synthesis Example 4) By the same operation as in Synthesis Examples 1 to 3, acryloyloxyethyltrimethylammonium chloride / methacryloyloxyethyltrimethylammonium chloride / acrylic acid = 35/50/15 (prototype-4), acryloyl Oxyethyltrimethylammonium chloride / acryloyloxyethylbenzyldimethylammonium chloride / acrylic acid = 50/35/15
(Prototype-5), methacryloyloxyethyltrimethylammonium chloride / acryloyloxyethylbenzyldimethylammonium chloride / acrylic acid = 35/5
0/15 (Prototype-6) was synthesized. The results are shown in Table 2.

Comparative Comparative Example As a comparative product, dimethylamine / epichlorohydrin / pentaethylenehexamine = 45/50/5 (molar ratio) (Comparative-1) was synthesized in an aqueous solution. The results are shown in Table 2.

(Comparative Synthesis Examples 2 to 3) By the same operation as in Synthesis Examples 1 to 3, acryloyloxyethyltrimethylammonium chloride / acrylamide / acrylic acid = 60.
/ 20/20 (Comparison-2), dimethylaminoethyl methacrylate / dimethylaminoethyl acrylate / acrylic acid / acrylamide = 20/40/20/20 (Comparison-
3) was synthesized respectively. The results are shown in Table 2.

(Synthesis Example 7) 117.5 g of ion-exchanged water and 28.5 g of 60% aqueous solution acrylic acid were charged, to which 28.5 g of 30% aqueous sodium hydroxide (90 equivalent% of acrylic acid) was added. I made it In this, 33.6 g of acrylamide 50% aqueous solution, acryloyloxyethyl trimethyl ammonium chloride, 80% aqueous solution 11
4.8 g, methacryloyloxyethyltrimethylammonium chloride, 61.6 g of 80% aqueous solution and 0.35 g of isopropyl alcohol were charged and completely dissolved. Separately, 126.0 g of isoparaffin having a boiling point of 190 ° C to 230 ° C was added to sorbitan monooleate 1
5.0 g was added and dissolved, and the monomer solutions were mixed and emulsified with a homogenizer at 3000 rpm for 10 minutes.
The produced emulsion was charged into a reaction tank equipped with a stirrer and a temperature control device, the internal temperature was kept at 33 to 35, and nitrogen substitution was carried out for 30 minutes. After that, 4,4-azobis (4-
1.8 g of a 5% solution of methoxy-2,4dimethyl) valeronitrile dissolved in dioxane (based on the monomer of 0.05)
%) Was added to initiate polymerization. After 5 hours from the start, 0.9 g of the above initiator solution was added and the polymerization was continued for another 5 hours. This is designated as Prototype-7. Moreover, the weight average molecular weight was measured by a molecular weight measuring device (DLS-7000 manufactured by Otsuka Electronics) by the static light scattering method. The results are shown in Table 2.

(Synthesis Examples 8 to 12) Prototypes 8 to 12 having the composition shown in Table 1 were synthesized by the water-in-oil emulsion polymerization method in the same manner as in Synthesis Example 7. The results are shown in Table 2.

(Comparative Synthesis Examples 4-5) By the same procedure as in Synthesis Example 7, acryloyloxyethyltrimethylammonium chloride / acrylamide / acrylic acid = 60/2.
0/20 (Comparative-4), dimethylaminoethyl methacrylate / dimethylaminoethyl acrylate / acrylic acid /
Acrylamide = 20/40/20/20 (Comparison-5)
Was synthesized using a water-in-oil emulsion polymerization method. The results are shown in Table 2.

[0046]

[Examples 1 to 15] Medium-quality paper raw materials (pH 6.55, turbidity 110) consisting of mechanical pulp, LBKP and flyer waste paper.
0FAU, total ss 2.63%, ash 0.20%, cation requirement 0.040 meq / L, zeta potential-
9 mV) 100 mL is sampled, set in a stirrer, and each of the prototypes 1 to 12 in Table 1 is added to the ss content of 350 ppm,
Stir for 60 seconds at 500 rpm. Then, No. The whole amount was filtered with a 41 (90 mm) filter paper, and the cation required amount of the filtrate was PCD-03 manufactured by Mutec.
The turbidity was measured with a mold and a HACH, DR2000P type turbidimeter. The results are shown in Table 3.

[0047]

Comparative Examples 1 to 5 For comparison, polycondensation type cationic polymer, dimethylamine / epichlorohydrin / polyamine reaction product (molecular weight: 30,000, cation equivalent value: 7.
51 meq / g) (Comparison-1), and Comparative Synthesis Examples 2 to 5
The polymers (Comparative-2 to Comparative-5) of Example 1 were subjected to the same operations as in Examples 1 to 15. The results are shown in Table 3.

[0048]

[Examples 13 to 24] Newsprint material made of mechanical pulp and waste newspaper (pH 5.03, turbidity 1350 FAU, total s)
s 2.40%, ash content 0.11%, cation requirement 0.0
56 meq / L, zeta potential-15 mV) 10
0 mL sample was collected, set in a stirrer, and prototype of synthesis example-1 to 1
Add 2 parts each for 500 ss and stir at 500 rpm for 60 seconds. Then, No.
The whole amount was filtered with a 41 (90 mm) filter paper, and the cation required amount of the filtrate was measured by PCD-03 type manufactured by Mutec Co., Ltd.
The turbidity was measured by HACH, DR2000P turbidimeter. The results are shown in Table 4.

[0049]

[Comparative Examples 6 to 10] Comparative Examples 1 to 5 of Comparative Synthesis Examples were tested in the same manner as in Examples 13 to 24. The results are shown in Table 4.

[0050]

[Table 1] DMQ: Acryloyloxyethyltrimethylammonium chloride DMC: Methacryloyloxyethyltrimethylammonium chloride ABC: Acryloyloxyethylbenzyldimethylammonium chloride AAC: Acrylic acid, AAM: Acrylamide: DMM: Dimethylaminoethyl methacrylate DMA: Dimethylamino acrylate ethyl

[0051]

[Table 2] Dispersion viscosity: mPa · s, molecular weight: 10,000

[0052]

[Table 3] Filtrate cation requirement: meq / L Filtrate turbidity: FAU

[0053]

[Table 4] Filtrate cation requirement: meq / L Filtrate turbidity: FAU

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08F 220/58 C08F 220/58 220/60 220/60 228/02 228/02 // D21C 9/08 D21C 9/08 D21H 21/02 D21H 21/02 F term (reference) 4J011 LA04 LA06 LB09 LB10 4J100 AB07Q AJ02Q AJ08Q AL08P AM15R AM21Q AP01Q BA03P BA32P BA56Q BC43P CA05 CA06 EA06 FA20 FA30 JA13 4L055 AG97 A06 FA22 FA89 AG22 FA22 FA89 AG22 FA22 FA89

Claims (7)

[Claims] 1. Two to five mol% selected from cationic monomers represented by the following general formulas (1) to (3),
Anionic monomer 5-50 represented by the following general formula (4)
After adding an amphoteric water-soluble polymer consisting of mol% and nonionic monomer 0 to 90 to the papermaking raw material before papermaking and treating the same,
A method for pretreating a raw material for papermaking, which comprises making a paper. [Chemical 1] General formula (1) General formula (2) General formula (3) R1, R2 and R3 are alkyl or alkoxyl groups having 1 to 3 carbon atoms, R4, R5 and R6 are alkyl or alkoxyl groups having 1 to 3 carbon atoms, R7 is hydrogen or methyl group, and R8 and R9 are An alkyl or alkoxyl group having 1 to 3 carbon atoms, R10 is a benzyl group,
Is oxygen or NH, B is an alkylene group having 2 to 4 carbon atoms or an alkoxylene group, and X1, X2 and X3 are anions, respectively. [Chemical 4] General formula (4) R11 is hydrogen, a methyl group or a carboxymethyl group, A
Is SO3, C6H4SO3, CONHC (CH3) 2C
H2SO3, C6H4COO or COO, R12 represents hydrogen or COOY2, Y1 or Y2 represents hydrogen or a cation, respectively. 2. The amphoteric water-soluble polymer is in an aqueous salt solution,
A polymeric dispersant soluble in the aqueous salt solution is allowed to coexist, and 5 to 95 mol% of two kinds selected from the cationic monomers represented by the general formulas (1) to (3), the following general formula: A particle size of 100 μm or less produced by dispersion-polymerizing a monomer mixture consisting of 5 to 50 mol% of anionic monomer represented by (4) and 0 to 90 of nonionic monomer under stirring. The pretreatment method for a papermaking raw material according to claim 1, which is a dispersion liquid containing the fine particles of 3. The pretreatment method for a papermaking raw material according to claim 2, wherein the polymer dispersant is ionic. 4. The pretreatment method for a papermaking raw material according to claim 2, wherein the salt constituting the aqueous salt solution contains at least one polyvalent anion salt. 5. The amphoteric water-soluble polymer contains 5 to 95 mol% of two kinds selected from the cationic monomers represented by the general formulas (1) to (3), and the following general formula (4) ) An anionic monomer represented by 5 to 50 mol% and a nonionic monomer 0 to 90 are used as a discontinuous phase, and a liquid hydrocarbon containing an oil-soluble emulsifier as a continuous phase. The method for pretreating a paper-making raw material according to claim 1, which comprises a dispersion liquid produced by forming a water-in-oil emulsion having the following formula and performing emulsion polymerization under stirring. 6. When the number of moles of the total amount of the cationic monomers in the monomer mixture is represented by C and the number of moles of the anionic monomer is represented by A, C and A have the following relationship. The pretreatment method for a papermaking raw material according to claim 2 or 5, characterized in that 0 ≦ C / A ≦ 6.0 7. The cationic monomers represented by the general formulas (1) to (3) are methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride and acryloyloxyethylbenzyldimethylammonium chloride, respectively. A thing,
The pretreatment method for a papermaking raw material according to claim 1, wherein the anionic monomer is (meth) acrylic acid and the nonionic monomer is (meth) acrylamide.