JP5217240B2 - Paper additive and paper making method using the same - Google Patents

Description

  The present invention relates to a paper additive and a paper manufacturing method. More specifically, when added to a pulp slurry, the paper has little adverse effect on paper water-disintegration and has excellent paper strength without impairing paper flexibility. The present invention relates to a paper additive having an enhancing effect and a papermaking method using the same.

Conventionally, in the papermaking process, various papermaking additives have been used to improve productivity or improve paper quality as the speed of the paper machine increases, and these two or more types can be used in combination. It is. In particular, paper strength enhancers are important chemicals for improving paper strength and productivity, and various types of paper strength enhancers are on the market. In addition, printing paper such as book paper and coated paper, and household thin paper such as tissue paper and toilet paper have flexibility as one of the important physical properties, especially due to recent demands for higher quality. Both paper strength and flexibility are being demanded.
For the purpose of improving paper strength, acrylamide polymers, cationized starch, polyamide-epichlorohydrin resin, melamine-formaldehyde resin, urea-formaldehyde resin, and the like are used. However, any of the paper strength enhancing agents has a drawback that the flexibility of the paper is impaired, and there is a problem that it is impossible to achieve both paper strength and flexibility.

In addition, it is known that anionic polysaccharides represented by carboxymethyl cellulose (hereinafter sometimes abbreviated as CMC) also have an effect of improving the strength of paper, but the degree of improvement in strength obtained is low, In addition, there is a problem that, unless a chemical having a cationic property such as a sulfuric acid band or a polyamide-epichlorohydrin resin is used in combination, it does not stay on paper and does not exhibit an effect. Various studies have been made for the purpose of improving the dry strength of this anionic polysaccharide. For example, by using a mixture of a water-soluble polysaccharide having a specific anionic group and an acrylamide polymer, the yield of the acrylamide polymer is improved and the paper quality is improved (see, for example, Patent Document 1). After the addition, mineral acid is added, and CMC is converted into an acid form, thereby reducing the solubility of CMC and fixing it to the fiber, thereby enhancing the effect of dry paper strength agent (for example, patent document) 2), cationized starch and carboxymethylcellulose are separately added to the pulp slurry for the purpose of enhancing paper strength (see, for example, Patent Document 3), or a starch having a cationic group and a polysaccharide having an anionic group. A method for enhancing the effect of a dry paper strength agent or the like by using a mixture is disclosed (for example, see Patent Document 4).

In the production of crepe paper such as tissue for the purpose of achieving both flexibility and paper strength, it is represented by specific softener components, wet paper strength enhancers represented by polyamide-epichlorohydrin resin, cationized starch and carboxymethylcellulose. A method of using a dry paper strength enhancer in combination is proposed (Patent Documents 5 to 9). However, in these methods, the compatibility between the flexibility and the paper strength is not satisfactory, and since the wet paper strength enhancer is used, its use is limited from the viewpoint of water decomposability and disaggregation. There was a problem with.
In addition, an aqueous composition comprising an ionic polymer and a polymer having an ionicity opposite to that of the polymer is disclosed, which is intended to impart useful rheological properties during the surface treatment of paper. is there. (Patent Document 10)
JP 2002-201587 A JP 09-291490 A JP-A-11-107188 JP 2005-65887 A JP-T 9-504580 Japanese National Patent Publication No. 9-504581 Japanese National Patent Publication No. 10-510886 Special table 2003-502519 gazette Japanese Patent Laid-Open No. 2005-124484 JP-T-2002-514673

  It is an object of the present invention to provide a paper additive having an excellent effect of enhancing paper strength without adversely affecting the water disintegration property of paper and without impairing paper flexibility, and a papermaking method using the same. To do.

  The inventors of the present invention have prepared a mixture obtained by previously mixing a specific cationic resin with a polysaccharide having a specific anionic group, with little adverse effect on the water degradability of paper, and without impairing the flexibility of the paper. The inventors have found that an excellent paper strength enhancing effect is exhibited, and have completed the present invention.

That is, the present invention
(1) Paper additive (A) dibasic, comprising at least one cationic resin selected from the following resins (A) to (D) and a water-soluble polysaccharide having an anionic group Polyamide polyamine resin formed by heat condensation of carboxylic acid compound and polyalkylene polyamine compound (B) Polyamide polyamine resin formed by heat condensation of dibasic carboxylic acid compound and polyalkylene polyamine compound, and amino in polyamide polyamine resin Polyamide polyamine-epihalohydrin resin obtained by reacting 0.5 mol or less of epihalohydrin with 1 mol of group (C) A heat-condensed dibasic carboxylic acid compound, polyalkylene polyamine compound and urea compound. Polyamide polyamine polyurea resin (D) dibasic carbo Reacting a polyamide polyamine polyurea resin obtained by heat condensation of an acid compound, a polyalkylene polyamine compound and a urea compound with 0.5 mol or less of an epihalohydrin with respect to 1 mol of an amino group in the polyamide polyamine polyurea resin. Polyamide polyamine polyurea-epihalohydrin resin obtained by
(2) The cationization degree at pH 3 of at least one cationic resin selected from the resins (A) to (D) is at least 1.5 meq / g · solids, and the cationization degree at pH 10 is at most 0. The paper additive of (1), which is .5 meq / g · solid,
(3) The mixing ratio in solid content of at least one cationic resin selected from the resins (A) to (D) in (1) or (2) and a water-soluble polysaccharide having an anionic group is 90 / A paper additive that is 10 to 10/90,
(4) The additive for paper, wherein the water-soluble polysaccharide having an anionic group of (1) or (3) is carboxymethylated starch or carboxymethylated cellulose,
(5) A papermaking method for making paper by adding the paper additive of (1) to (4) to a pulp slurry,
(6) A papermaking method, wherein the paper additive and the paper softener of (1) to (4) are added to a pulp slurry for papermaking.

    According to the present invention, when paper is made using a pulp slurry prepared by adding a mixture of a specific cationic resin and a water-soluble polysaccharide having a specific anionic group in advance, the flexibility of the resulting paper is obtained. It is possible to provide a paper additive having an excellent effect of improving the dry paper strength without impairing water decomposability, and using these does not impair the flexibility and water decomposability of paper. In addition, it is possible to provide a papermaking method capable of improving the dry paper strength. The specific additive for paper according to the present invention has the above technical effect by previously mixing a specific cationic resin and a water-soluble polysaccharide having a specific anion group before preparing a pulp slurry. The technical effect is achieved in a pulp slurry prepared by sequentially mixing a specific cationic resin, a water-soluble polysaccharide having a specific anionic group, and other pulp slurry forming components. It is specific in that it cannot.

  The water-soluble polysaccharide having an anionic group used in the paper additive according to the present invention is at least chemically modified starch such as carboxymethylation, sulfoethylation, urea phosphate esterification, sulfosuccinate esterification, cellulose, etc. Class of derivatives. Further, two or more of these may be used in combination. Of these, preferred are carboxymethylated starch and carboxymethylated cellulose.

In using the water-soluble polysaccharide (A) having an anionic group, it may be treated thermally and / or mechanically, or may be used after being decomposed oxidatively or enzymatically.

The viscosity of a 1% aqueous solution of a water-soluble polysaccharide having an anionic group at 25 ° C. is preferably 2000 mPa · s or less, and more preferably 1.0 to It is preferably 1000 mPa · s.

In the present invention, among the water-soluble polysaccharides having an anionic group, carboxymethylated starch, carboxymethylated cellulose and their metal salts, ammonium salts are preferable, from the influence on paper flexibility, the paper strength improvement effect, Carboxymethylated cellulose or a metal salt or ammonium salt thereof is more preferable. In general, cellulose or starch can be obtained by immersing cellulose or starch in concentrated sodium hydroxide solution and reacting it with monochloroacetic acid.

In addition, products having various etherification degrees and viscosities are commercially available for carboxymethylated cellulose, but can be suitably used in the present invention as long as they have sufficient water solubility. If the degree of etherification is too high, electrostatic repulsion will be strong and fixing to the pulp will be difficult, and if it is too low, the water solubility will be lowered, and there will be a problem that it will be difficult to use.

  In producing the polyamide polyamine resin (A), the polyamide polyamine-epihalohydrin resin (B), the polyamide polyamine polyurea resin (C), and the polyamide polyamine polyurea-epihalohydrin resin (D) used in the paper additive according to the present invention. , Dibasic carboxylic acid compound (a), polyalkylene polyamine compound (b), epihalohydrin (c), and urea compound (d) are polyamide polyamine resin (A), polyamide polyamine-epihalohydrin resin (B), polyamide Regardless of the types of polyamine polyurea resin (C) and polyamide polyamine polyurea-epihalohydrin resin (D), they are common raw materials.

  Examples of the dibasic carboxylic acid compound (a) include dibasic carboxylic acid and derivatives thereof. A dibasic carboxylic acid has two carboxylic acids in the molecule. Examples of the dibasic carboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brassic acid, dodecanedioic acid and the like. A dibasic carboxylic acid having a number of 5 to 10 is preferred. Examples of the derivatives of dibasic carboxylic acids include mono- or diesters of these dibasic carboxylic acids, or acid anhydrides. The monobasic carboxylic acid mono- or diester is preferably an ester of a lower alcohol having 1 to 5 carbon atoms, particularly preferably 1 to 3 carbon atoms, such as an ester of methyl alcohol, ethyl alcohol, or propyl alcohol. be able to. Examples of the acid anhydride include an intramolecular dehydration condensate of a free acid and a condensate of a lower carboxylic acid, preferably a lower carboxylic acid having 1 to 5 carbon atoms. Particularly preferred industrially preferred dibasic carboxylic acid compounds include adipic acid, glutaric acid dimethyl ester, and adipic acid dimethyl ester. The above-mentioned various dibasic carboxylic acid compounds can be used by selecting one kind thereof, or two or more selected kinds can be used in combination. In addition to the dibasic carboxylic acid compound, it is also possible to use a derivative having three or more carboxylic acids and / or carboxylic acid esters or acid anhydrides thereof in the molecule, such as citric acid.

  The polyalkylene polyamine compound (b) only needs to have two or more amino groups. Examples thereof include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, iminobispropylamine, and the like. Is preferably diethylenetriamine. In this invention, these 1 type, or 2 or more types can be used. Moreover, 1 type, or 2 or more types of alkylenediamines, such as ethylenediamine, propylenediamine, and hexamethylenediamine, can also be used with a polyalkylene polyamine compound.

  Epihalohydrin (c) includes epichlorohydrin, epibromohydrin, etc. Among them, epichlorohydrin is preferable.

  Examples of the urea compound (d) include urea, thiourea, guanylurea, phenylurea, methylurea, and dimethylurea. Of these, urea is particularly preferred industrially. With these urea compounds (d), compounds having one or more N-unsubstituted amide groups capable of undergoing an amide exchange reaction with amino groups, for example, aliphatic amide compounds such as acetamido and propionamide, benzamide, phenylacetamide and the like Aromatic amide compounds can also be used.

The polyamide polyamine resin (A) in this invention is obtained by reacting the dibasic carboxylic acid compound (a) and the polyalkylene polyamine compound (b) in any order or simultaneously.
As the reaction ratio of the polyalkylene polyamine compound (b) and the dibasic carboxylic acid compound (a) in obtaining the polyamide polyamine resin (A), the polyalkylene polyamine compound (b) and the dibasic carboxylic acid compound (a )) In a range of 0.8 to 1.4: 1, particularly 0.8 to 1.2: 1, there is little decrease in the flexibility of the paper and a useful paper strength improvement effect is exhibited. Paper additives are easy to obtain. When the above molar ratio is less than 0.8, the paper strength is improved, but sufficient storage stability may not be obtained. When the above molar ratio is larger than 1.4, an effect commensurate with increasing the molar ratio may not be expected although an improvement in paper strength is achieved.

  The polyamide polyamine-epihalohydrin resin (B) in the present invention is obtained by reacting the polyamide polyamine resin (A) with the epihalohydrin (c).

  The reaction ratio of the epihalohydrin (c) to the polyamide polyamine resin (A) is 0.5 mol or less, preferably 0.01 to 0.5, more preferably relative to 1 mol of the amino group of the polyamide polyamine resin (A). 0.01 to 0.35. If the amount is more than 0.5 mol, the paper strength improvement effect is exhibited, but the wet strength is expressed, so that the water disintegration property and disaggregation property of paper may be deteriorated, and further when mixed with an anionic polysaccharide. The viscosity may increase over time. The amino group in the polyamide polyamine resin (A) may be a primary amino group, a secondary amino group, or a tertiary amino group.

  The polyamide polyamine polyurea resin (C) in the present invention is obtained by reacting the polyalkylene polyamine compound (b), the dibasic carboxylic acid compound (a) and the urea compound (d) in any order or simultaneously. be able to. For example, a method of reacting a urea compound (d) after reacting a polyalkylene polyamine compound (b) with a dibasic carboxylic acid compound (a), a polyalkylene polyamine compound (b) and a urea compound (d) Either the method of reacting with the dibasic carboxylic acid compound (a) after the reaction, or the method of reacting the polyalkylene polyamine compound (b), the dibasic carboxylic acid compound (a) and the urea compound (d) simultaneously may be used. .

  The polyamide polyamine polyurea-epihalohydrin resin (D) in this invention is obtained by reacting the polyamide polyamine polyurea resin (C) with the epihalohydrin (c).

  In synthesizing the polyamide polyamine polyurea resin (C), a reaction ratio of 1.0 mol of the dibasic carboxylic acid compound (a) to 0.8 to 1.4 mol of the polyalkylene polyamine compound (b), and The reaction ratio is preferably 0.05 to 1.0 mol of urea compound (d) with respect to 1 mol of amino group of polyalkylene polyamine compound (b).

  The reaction ratio of the epihalohydrin (c) to the polyamide polyamine polyurea resin (C) is 0.5 mol or less, preferably 0.01 to 0.5, relative to 1 mol of amino groups of the polyamide polyamine polyurea resin (C). More preferably, it is 0.01-0.35. If the amount is more than 0.5 mol, the paper strength improvement effect is exhibited, but the wet strength is manifested, so that the water disintegration property and disaggregation property of paper may be deteriorated. Furthermore, the water-soluble polysaccharide having an anion group and When mixed, it may thicken over time. The amino group of the polyamide polyamine polyurea resin (C) may be any of a primary amino group, a secondary amino group, and a tertiary amino group.

  The amino group of the polyalkylene polyamine compound (b) is reacted with the carboxylic acid group (—COOH) of the dibasic carboxylic acid compound (a) and / or its derivative group (for example, ester group, acid anhydride group, etc.). When the raw material is charged, the reaction heat generated during the charging of the raw material is used, or the dehydration and / or dealcoholization reaction is carried out by heating from the outside, and the reaction temperature is adjusted to 110 to 250 ° C., particularly 120 to 180 ° C. It is preferable. The reaction temperature conditions are appropriately changed depending on whether the starting dibasic carboxylic acid compound (a) is a carboxylic acid or a derivative thereof. At this time, a sulfonic acid compound such as sulfuric acid, benzenesulfonic acid, and paratoluenesulfonic acid can also be used as a catalyst for the polymerization reaction. The amount to be used is preferably 0.005 to 0.1 mol, particularly 0.01 to 0.05 mol, per 1 mol of the polyalkylene polyamine compound (b).

  For example, when the amino group of the polyamide polyamine resin (A) is reacted with the urea compound (d), an amide exchange reaction is performed while removing generated ammonia out of the system. The reaction temperature at this time is preferably 80 to 180 ° C., particularly 90 ° C. to 160 ° C., since it is difficult for the viscosity to increase rapidly and the reaction proceeds moderately. Moreover, although reaction time is dependent on reaction temperature, it is 30 minutes-10 hours normally.

The amount of amino groups present in the polyamide polyamine resin (A) and the polyamide polyamine polyurea resin (C) in the present invention is the amount of hydrochloric acid necessary to neutralize the amine contained in 1 g of the sample according to the following formula. It can be determined by measuring.
Amino group content (mmol / g) = V × F × 0.5 / S
V: titration amount of 1/2 N hydrochloric acid solution F: titer of 1/2 N hydrochloric acid solution S: solid content (g) of sample collected

  The reaction between the polyamide polyamine resin (A) or the polyamide polyamine polyurea resin (C) and the epihalohydrin (c) is carried out at a reaction solution concentration of 10 to 80% by mass, and the reaction temperature depends on the reaction concentration, but is 5 to 90 ° C. It is preferable.

  In particular, the reaction between the polyamide polyamine resin (A) or the polyamide polyamine polyurea resin (C) and the epihalohydrin (c) causes the epihalohydrin (c) to be added to the polyamide polyamine resin (A) or the polyamide polyamine polyurea resin (C). It is preferable to go through a step (sometimes referred to as a primary step) and a step of increasing viscosity by a crosslinking reaction (sometimes referred to as a secondary step).

  In the reaction of the polyamide polyamine resin (A) or the polyamide polyamine polyurea resin (C) and the epihalohydrin (c) in the primary step, the concentration of the polyamide polyamine resin (A) or the polyamide polyamine polyurea resin (C) is 30 to 30. It is preferable to carry out with 80 mass%, especially 40-70 mass% aqueous solution, since reaction is easy to advance moderately without accompanying the rapid viscosity rise of the said aqueous solution. It is preferable that the reaction temperature in this primary step is not accompanied by a sudden increase in viscosity and that the efficiency of addition of epihalohydrin (c) is not lowered, and the reaction temperature is 5 to 50 ° C., particularly 10 to 45. It is preferable to proceed the reaction in the range of 15 ° C., more preferably 15 to 35 ° C. The reaction time is preferably 1 to 10 hours.

  As the secondary step, it is preferable to continue the reaction by diluting or not diluting the reaction solution obtained in the primary step and heating the reaction temperature to 30 to 90 ° C., particularly 50 to 75 ° C. . Usually, when the reaction temperature in the secondary step becomes higher than the above temperature range, the viscosity of the reaction mixture may increase rapidly, making it difficult to control the reaction. The concentration of the polyamide polyamine-epihalohydrin resin (B) or polyamide polyamine polyurea-epihalohydrin resin (D) produced in the first step is preferably adjusted to 10 to 70%, particularly 10 to 50%. .

  The reaction in the secondary step is carried out until the viscosity at 25 ° C. of the aqueous solution in which the solid content of the product resulting from the cross-linking reaction is 15% by mass reaches 10 to 100 mPa · s, preferably 15 to 80 mPa · s. , It is preferable because a polyamide polyamine-epihalohydrin resin (B) and a polyamide polyamine polyurea-epihalohydrin resin (D) excellent in storage stability can be easily obtained.

  It is preferable to add water to the reaction product solution in which the crosslinking reaction is proceeding in the secondary step to stop the crosslinking reaction, cool the reaction product solution, and simultaneously adjust the solid content to 10 to 50%. The density | concentration of solid content can be adjusted with the addition amount of water. Furthermore, a reaction product solution in which the crosslinking reaction is stopped with at least one acid selected from inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid, particularly inorganic acids not containing halogen, and organic acids such as formic acid and acetic acid. In addition, the storage stability of the obtained polyamide polyamine-epihalohydrin resin (B) and polyamide polyamine polyurea-epihalohydrin resin (D) is preferably improved by adjusting the pH to 1 to 6, particularly pH 2 to 5. It is preferable.

  The degree of cationization of the polyamide polyamine polyurea resin (B) and the polyamide polyamine polyurea resin (D), which is a reaction product of the polyamide polyamine resin (A) and the polyamide polyamine polyurea resin (C) with the epihalohydrin (c), is The cationization degree at pH 3 is preferably at least 1.5 meq / g · solids, more preferably at least 2.5 meq / g · solids. When the degree of cationization at pH 3 is less than 1.5 meq / g · solids, sufficient cationicity cannot be obtained, and the paper strength improvement effect may not be sufficiently obtained. Furthermore, it is preferable that the degree of cationization at pH 10 is at most 0.5 meq / g · solid. When the degree of cationization at pH 10 is higher than 0.5 meq / g · solid, the viscosity may increase over time when mixed with an anionic polysaccharide.

  The degree of cationization can be measured by a colloid titration method (titration with potassium polyvinyl sulfate (PVSK)).

Of at least one cationic resin selected from the resins (A) to (D), the polyamide polyamine polyurea-epihalohydrin resin (D) from the stability over time of viscosity when mixed with a water-soluble polysaccharide having an anionic group. ) Is preferred.

  The paper additive according to the present invention is selected from the polyamide polyamine resin (A), the polyamide polyamine-epihalohydrin resin (B), the polyamide polyamine polyurea resin (C), and the polyamide polyamine polyurea-epihalohydrin resin (D). It may be a mixture of at least one specific compound and a water-soluble polysaccharide having an anionic group, and contains the specific compound and other additives or solvents as long as the object of the present invention is not impaired. You may do it.

  Examples of the other additives include a dispersant, an antifoaming agent and a preservative.

  Examples of the solvent include water and alcohols such as isopropyl alcohol.

  The mixing of the cationic resin according to the present invention and the water-soluble polysaccharide having an anionic group is not performed in the pulp slurry but must be performed before preparing the pulp slurry. This is because, even if the pulp slurry is prepared by mixing the cationic resin according to the present invention, the water-soluble polysaccharide having an anionic group and other pulp slurry forming components, a sufficient effect cannot be obtained.

  Mixing of the cationic resin and the water-soluble polysaccharide having an anionic group can be carried out by any known method, and the water-soluble polysaccharide having a cationic resin and an anionic group in either a wet or dry atmosphere. Can be carried out by mixing. In mixing, an appropriate solvent such as water is preferably used.

  The mixing ratio of the cationic resin and the water-soluble polysaccharide having an anion group in the present invention is usually 90/10 to 10/90, and preferably 70/30 to 30/70. If the proportion of the water-soluble polysaccharide having an anionic group is less than 10%, it may be difficult to achieve both paper flexibility and strength, and if it exceeds 90%, the degree of improvement in paper strength may be low. . The mixing ratio is based on solid content.

  The papermaking method of the present invention is a method for papermaking a pulp slurry obtained by mixing the paper additive of the present invention obtained as described above and other components forming the pulp slurry. The paper additive of the present invention can be obtained by previously mixing the cationic resin and the water-soluble polysaccharide having an anionic group at the above ratio. This paper additive may be used by adding it to the stock (pulp slurry), or may be used by coating on the surface of the base paper (that is, coating the surface). Furthermore, the paper additive of the present invention is added to the stock, and then the paper additive of the present invention is coated on the surface of the base paper obtained by papermaking and drying. Additives may be used.

  When the paper additive of the present invention is used by adding it to the paper stock, there is no particular limitation on the method of use, and it can be diluted with industrial water or the like, or can be added as it is. In any case, a method similar to a general paper manufacturing method can be adopted except that the paper additive of the present invention is used.

  Preferred methods for applying the paper additive of the present invention to surface coating include spray coating, flexo printing or gravure printing using a printing press, size press, gate roll coater, bill blade coater or calendar. In any case, a method similar to a general paper or paperboard manufacturing method can be adopted except that the paper additive of the present invention is used.

  The paper additive used in the present invention is usually added in a solid content of 0.01 to 3% by weight, preferably 0.03 to 1.0% by weight, based on the solid content of the paper. When applied to coating, it may be applied at a usage rate of 0.05 to 3% by weight, preferably 0.05 to 1.5% by weight, per unit weight of paper.

  In producing the paper of the present invention, a paper softener can be used in combination. By using the paper softener and the paper additive of the present invention in combination, it is possible to obtain higher flexibility and higher paper strength than the paper softener alone.

  Examples of the softener for paper include ester compounds of fatty acids and polyhydric alcohols, fatty acids, nonionic surfactants having an alkyl group and / or an alkenyl group represented by alkylene oxide adducts of higher alcohols, fatty acid amides, Examples include epichlorohydrin adducts of amides of fatty acids and polyalkylene polyamines, imidazoline compounds having a long-chain alkyl group, and cationic surfactants having an alkyl group and / or an alkenyl group. Among these, in particular, a paper containing a nonionic surfactant having an alkyl group and / or alkenyl group (component a), or a cationic surfactant having an alkyl group and / or alkenyl group (component a). When the softener for paper and the additive for paper of the present invention are used in combination, it is preferable in that higher flexibility and paper strength can be obtained.

  The nonionic surfactant (a component) used for the paper softener has an alkyl group and / or alkenyl group, and has an alkyl group having 6 to 24 carbon atoms and / or an alkenyl group having 6 to 24 carbon atoms. It is preferable to have the hydrophobic part.

  As such a nonionic surfactant, a nonionic surfactant in which an oxyalkylene group is added to a higher alcohol or higher fatty acid, an ester of a polyhydric alcohol and a fatty acid, and the following general formulas (1) and (2) ) (Hereinafter referred to as Compound I). These may be used alone or in combination of two or more.

Examples of the nonionic surfactant in which an oxyalkylene group is added to a higher alcohol or a higher fatty acid include compounds represented by the following general formula (3).
^{_{R 1 -A 1 - (EO)}} m (PO) n -CO-R 2 ··· (1)
R ¹ —O— (EO) _m (PO) _n —R ² (2)
R ¹ -A ^1- (EO) _m (PO) _n H (3)
(In the formula, —A ¹ — represents —O— or —COO—, and R ¹ and R ² represent an alkyl group having 6 to 24 carbon atoms, preferably 10 to 22 carbon atoms, or 6 to 24 carbon atoms, preferably Represents 10 to 22 alkenyl groups, and R ¹ and R ² may be the same or different, E represents an ethylene group, P represents a propylene group, and the sum of m and n is 1 -60, preferably 2-40, where m and n are the average number of moles added.
Of the nonionic surfactants represented by the general formulas (1) to (3), the nonionic surfactants represented by the general formulas (1) and (2) are preferable, and the general formula (1) is more preferable. It is a nonionic surfactant shown by these.

  The compound represented by the general formula (1) is, for example, an alcohol having 6 to 24 carbon atoms, preferably an alcohol having 10 to 22 or ethylene oxide in 1 mol of a fatty acid having 7 to 25 carbon atoms, preferably 11 to 23 carbon atoms, and After adding propylene oxide, it can be obtained by esterification with 1 mol of a fatty acid having 7 to 25 carbon atoms, preferably 11 to 23 carbon atoms. The addition form of ethylene oxide and / or propylene oxide may be random or block, and is an alcohol having 6 to 24 carbon atoms, preferably 10 to 22 carbon atoms, or 1 mol of fatty acid having 7 to 25 carbon atoms, preferably 11 to 23 carbon atoms. 1 to 60 mol, preferably 2 to 40 mol. When it exceeds 60 mol, the softening effect may be lowered.

  The compound represented by the general formula (2) has, for example, 6 to 24 carbon atoms, and preferably 6 to 22 carbon atoms after adding ethylene oxide and / or propylene oxide to 1 mole of alcohol having 10 to 22 carbon atoms. 24, preferably 10 to 22 alcohol or obtained by etherification with 1 mole of halogenated alkyl having 6 to 24, preferably 10 to 22 carbon atoms. Can do. The addition form of ethylene oxide and / or propylene oxide may be random or block, and a ratio of 1 to 60 moles, preferably 2 to 40 moles per mole of alcohol having 6 to 24 carbon atoms, preferably 10 to 22 carbon atoms. It is added with. When it exceeds 60 mol, the softening effect may be lowered.

  The compound represented by the general formula (3) is, for example, an alcohol having 6 to 24 carbon atoms, preferably 10 to 22 alcohols or 7 to 25 carbon atoms, preferably 1 to 23 moles of fatty acids having 11 to 23 carbon atoms, and It can be obtained by adding propylene oxide. The addition form of ethylene oxide and / or propylene oxide may be random or block, and is an alcohol having 6 to 24 carbon atoms, preferably 10 to 22 carbon atoms, or 1 mol of fatty acid having 7 to 25 carbon atoms, preferably 11 to 23 carbon atoms. 1 to 60 mol, preferably 2 to 40 mol. When it exceeds 60 mol, the softening effect may be lowered.

  The alcohol having 6 to 24 carbon atoms may be any of linear alcohol, branched chain alcohol, saturated alcohol, and unsaturated alcohol. Among these various alcohols, alcohols having 10 to 22 carbon atoms are preferable, and lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, and oleyl alcohol are particularly preferable. These may be used alone or in combination of two or more.

  The fatty acid having 7 to 25 carbon atoms may be any of linear fatty acid, fatty acid having a branched chain, saturated fatty acid, and unsaturated fatty acid. Among these various fatty acids, fatty acids having 10 to 22 carbon atoms are preferable, and lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, and oleic acid are particularly preferable. These may be used alone or in combination of two or more.

  Examples of the cationic surfactant (component B) used in the present invention include primary amines, secondary amines, tertiary amines, and quaternary ammonium salts. These may be used alone or in combination of two or more. In particular, a quaternary ammonium salt is preferable.

As primary amines, compounds represented by the following general formula: R ⁸ —NH ₂ (6)
(In the formula, R ⁸ represents one type selected from an alkyl group having 6 to 24 carbon atoms and an alkenyl group having 6 to 24 carbon atoms.)
Specific examples include oleylamine, laurylamine, and stearylamine.

As secondary amines, compounds represented by the following general formula: R ⁹ R ¹⁰ —NH (7)
(However, in the formula, R ⁹ represents one selected from an alkyl group having 6 to 24 carbon atoms and an alkenyl group having 6 to 24 carbon atoms, and R ¹⁰ represents (EO) _m (PO) _n H, carbon number) 1 type chosen from a C1-C24 alkyl group and a C1-C24 alkenyl group, said E shows an ethylene group, said P shows a propylene group, and the sum total of m and n is 1-60. (Note that m and n are the average number of moles added.)
Specific examples include dioleylamine and monooleyl monomethylamine.

As tertiary amines, compounds represented by the following general formula: R ¹¹ R ¹² R ¹³ N (8)
(However, in the formula, R ¹¹ represents one selected from an alkyl group having 6 to 24 carbon atoms and an alkenyl group having 6 to 24 carbon atoms, and R ¹² and R ¹³ are (EO) _m (PO) _n. H, one selected from an alkyl group having 1 to 24 carbon atoms, and an alkenyl group having 1 to 24 carbon atoms, and R ¹² and R ¹³ may be the same as or different from each other. Represents an ethylene group, P represents a propylene group, and the total of m and n is 1 to 60, where m and n are the average number of moles added.
Specific examples of the tertiary amines include polyoxyalkylene dioleyl amine, polyoxyalkylene ethylene glycol lauryl amine, dimethyl monooleyl amine, and monomethyl dioleyl amine.

Examples of the quaternary ammonium salt include a compound represented by the following general formula and a quaternary salt having an imidazoline ring. These may be used alone or in combination of two or more.
R ¹⁴ R ¹⁵ R ¹⁶ (CH ₃ ) N ⁺ X ⁻ (9)
(However, in the formula, R ¹⁴ is an alkyl group having 6 to 24 carbon atoms or an alkenyl group having 6 to 24 carbon atoms, and R ¹⁵ and R ¹⁶ are (EO) _m (PO) _n H, 1 to 24 carbon atoms). R ¹⁵ and R ¹⁶ may be the same as or different from each other, X ⁻ is an anion, and E is an anion. An ethylene group, wherein P represents a propylene group, and the total of m and n is 1 to 60. The addition form of ethylene oxide and / or propylene oxide may be random or block, where m and n are Average number of moles added.)
Specific examples of the quaternary ammonium salt represented by the general formula (9) include trimethyl monolauryl ammonium chloride, trimethyl monocetyl ammonium chloride, trimethyl monopalmityl ammonium chloride, trimethyl monostearyl ammonium chloride, and trimethyl monooleyl. Ammonium chloride, trimethyl monobehenyl ammonium chloride, dimethyl dilauryl ammonium chloride, dimethyl dicetyl ammonium chloride, dimethyl dipalmityl ammonium chloride, dimethyl distearyl ammonium chloride, dimethyl dioleyl ammonium chloride, dimethyl dibehenyl ammonium chloride, polyalkyleneoxy monomethyl Dioleyl ammonium chloride, bis Polyalkyleneoxy) monomethyl mono-oleyl ammonium chloride.

  Among these, trimethyl monostearyl ammonium chloride, trimethyl monooleyl ammonium chloride, dimethyl dilauryl ammonium chloride, dimethyl dioleyl ammonium chloride, polyalkyleneoxy monomethyl dioleyl ammonium chloride, and bis (polyalkyleneoxy) monomethyl monooleyl ammonium chloride are preferable.

  Examples of the quaternary ammonium salt having an imidazoline ring include compounds represented by the following general formula (10). These may be used alone or in combination of two or more.

（但し、式中、Ｒ^１７は炭素数６〜２４のアルキル基又は炭素数６〜２４のアルケニル基を、Ｒ^１８は炭素数１〜２４のアルキル基又は炭素数１〜２４のアルケニル基を示し、Ｘ⁻は陰イオンである。）
上記一般式（５）で表されるイミダゾリン環を有する４級アンモニウム塩としては、具体的な化合物としては１−ヒドロキシエチル−１−エチル−２−オレイルイミダゾリンエチル硫酸塩、１−ヒドロキシエチル−１−メチル−２−オレイルイミダゾリンクロライド、１−ヒドロキシエチル−１−エチル−２−ラウリルイミダゾリンエチル硫酸塩などが挙げられる。

(In the formula, R ¹⁷ represents an alkyl group having 6 to 24 carbon atoms or an alkenyl group having 6 to 24 carbon atoms, and R ¹⁸ represents an alkyl group having 1 to 24 carbon atoms or an alkenyl group having 1 to 24 carbon atoms. , X ^- is an anion).
Specific examples of the quaternary ammonium salt having an imidazoline ring represented by the general formula (5) include 1-hydroxyethyl-1-ethyl-2-oleylimidazoline ethyl sulfate, 1-hydroxyethyl-1 -Methyl-2-oleylimidazoline chloride, 1-hydroxyethyl-1-ethyl-2-laurylimidazoline ethyl sulfate and the like.

  Examples of the components other than the above include monomethyl ester quaternary salt, dimethyl diester quaternary salt, trimethyl diester quaternary salt, ester amide type tertiary salt and the like. Examples of the quaternary salt of monomethyl ester include triethanolamine which is diesterified with a fatty acid having 7 to 25 carbon atoms, preferably 11 to 23, such as stearic acid, and quaternized with dimethyl sulfate. Examples of the salt include N-methyldiethanolamine diesterified with a fatty acid having 7 to 25 carbon atoms, preferably 11 to 23, for example, oleic acid, and quaternized with methyl chloride. Examples include 3-dimethylamino-1,2-propanediol, which is diesterified with a fatty acid having 7 to 25 carbon atoms, preferably 11 to 23 carbon atoms, such as oleic acid, and quaternized with methyl chloride. As the salt, N- (2-hydroxyethyl) -N-methyl-1,3-propanedi Carbon atoms and Min 7-25, preferably fatty acids of 11 to 23, for example esterified with oleic acid, amidation, and the like those tertiary ammonium salt is neutralized with hydrochloric acid.

  The paper softener may be a mixture of the component A and component A. By mixing the component A and the component A, the fixing of the component A to the pulp can be dramatically improved. The mixing ratio of component A and component A is usually component A / component A = 100 / 0.5 to 100/20, preferably component A / component B = 100/2 to 100/10.

  Thus, by adding the obtained paper additive of the present invention to the paper stock, an excellent effect of improving the dry paper strength can be exhibited without impairing the flexibility and water disintegration property of the paper.

Additives such as fillers, sulfate sulfate, sizing agents, dry paper strength improvers, wet paper strength improvers, paper thickness improvers, moisturizers, yield improvers, and drainage improvers are also required for each paper type. In order to express the physical properties, it may be used as necessary. These may be used alone or in combination of two or more. Further, these can be mixed with the paper additive of the present invention in advance and added to the paper stock.

  The pulp slurry used in the papermaking method of the present invention contains pulp, and has a form that is formed into a slurry by dispersing the pulp with an aqueous solvent. The pulp slurry in the present invention may be an acidic pulp slurry using aluminum sulfate, or a neutral pulp slurry using no or a small amount of aluminum sulfate.

  Examples of the pulp include bleached kraft pulp and sulfite pulp, bleached unbleached chemical pulp, groundwood pulp, mechanical pulp, and thermomechanical pulp. Waste paper pulp such as deinked waste paper can be mentioned, and one or more of these can be used. Moreover, various additives other than pulp can also be used for a pulp slurry as needed.

  In the papermaking method of the present invention, additives such as fillers, sulfated soil, sizing agents, dry paper strength improvers, wet paper strength improvers, paper thickness improvers, humectants, yield improvers, and freeness improvers are also included. In order to express the physical properties required for each paper type, they may be used as necessary. These may be used alone or in combination of two or more. Further, these can be mixed with the paper additive of the present invention in advance and added to the paper stock.

  Examples of the filler include clay, talc, and calcium carbonate. These may be used alone or in combination of two or more. Sizing agents include fatty acid soap sizing agents such as sodium stearate, rosin, reinforced rosin, and rosin ester sizing agents, aqueous emulsions of alkenyl succinic anhydride, aqueous emulsions of 2-oxetanone, aqueous emulsions of paraffin wax, Examples thereof include a cationic sizing agent obtained by a reaction of a carboxylic acid and a polyvalent amine, an aqueous emulsion of a reaction product of an aliphatic oxyacid and an aliphatic amine or an aliphatic alcohol, and a cationic styrene sizing agent. These may be used alone or in combination of two or more.

  Examples of the dry paper strength improver include anionic polyacrylamide, cationic polyacrylamide, amphoteric polyacrylamide, cationized starch, and amphoteric starch. These may be used alone or in combination of two or more. Also good. Examples of the wet paper strength improver include polyamide / epichlorohydrin resin, melamine / formaldehyde resin, and urea / formaldehyde resin. These may be used alone or in combination with anionic polyacrylamide. Examples of paper thickness improvers include ester compounds of fatty acids and polyhydric alcohols, fatty acid, alkylene oxide adducts of higher alcohols, fatty acid amides, epichlorohydrin adducts of amides of fatty acids and polyalkylene polyamines, and long-chain alkyl groups. Examples thereof include imidazoline-based compounds, cationic surfactants, and the like, which may be used alone or in combination of two or more. Examples of the yield improver include anionic, cationic or amphoteric high molecular weight polyacrylamide, combined use of silica sol and cationized starch, and combined use of bentonite and cationic high molecular weight polyacrylamide. These may be used alone or in combination of two or more. Examples of the drainage improver include polyethyleneimine, cationic, amphoteric or anionic polyacrylamide. These may be used alone or in combination of two or more. In addition, with a size press, gate roll coater, bill blade coater, calendar, etc., surface paper strength improvers such as starch, polyvinyl alcohol and acrylamide polymers, dyes, coating colors, surface sizing agents, anti-slip agents, etc., as necessary May be applied. These may be used alone or in combination of two or more.

  Although it does not restrict | limit especially as paper obtained by the paper manufacturing method of this invention, Various paper and paperboard are mentioned. Paper types include PPC paper, inkjet printing paper, laser printer paper, form paper, thermal transfer paper, thermal recording base paper, pressure sensitive recording base paper, etc., photographic paper and its base paper, art paper, cast coated paper, high quality Coated paper such as coated paper, wrapping paper such as kraft paper, pure white roll paper, tissue paper, toilet paper, towel paper, household paper such as kitchen paper, other wallpaper base paper, notebook paper, book paper, various printing papers, newspapers Examples include various types of paper (paper) such as paper, paperboard for paper containers such as Manila balls, white balls, and chip balls, and paperboard such as liners and base paper for gypsum boards.

  Examples of the present invention and comparative examples will be specifically described below, but the present invention is not limited to these examples. In each example, “%” is “% by mass” unless otherwise specified.

Example 1 (Production Example of Paper Additive Containing Polyamide Polyamine Resin (A) and Carboxymethylated Cellulose)
A 500 mL four-necked round bottom flask equipped with a thermometer, a condenser, a stirrer, and a nitrogen inlet tube was charged with 105.3 g (1.02 mol) of diethylenetriamine, and 146.1 g (1 mol) of adipic acid was added with stirring. The temperature was raised while removing the generated water out of the system, and the reaction was carried out at 170 ° C. for 3 hours. Subsequently, water was gradually added to obtain a polyamide polyamine resin aqueous solution 1 having a solid content of 50%. The degree of cationization by the colloid titration method was 4.9 meq / g · solids at pH 3, and 0.01 meq / g · solids at pH 10. After adding 154.8 g of water to 30 g of this polyamide polyamine resin aqueous solution, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 10 mPa · s, degree of etherification 0.5) for 10 minutes. The mixture was added little by little, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% and a ratio of polyamide polyamine resin (A) to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 1.

(Example 2) (Production Example of Paper Additive Containing Polyamide Polyamine-Epihalohydrin Resin (B) and Carboxymethylated Cellulose)
A 500 ml four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a nitrogen inlet tube was charged with 200 g (0.49 mol as amino group) of the polyamide polyamine resin aqueous solution obtained in Example 1, and 20 After adding 17 g of epichlorohydrin at 0.3 ° C. (0.37 mol based on amino group), the mixture was heated to 30 ° C. and kept at the same temperature for 1 hour. Next, 233 g of water was added and heated to 50 ° C., and kept at the same temperature until the viscosity reached 200 mPa · s (25 ° C.), then 30% sulfuric acid and water were added to adjust the pH to 6, and the solid content to 30 % Polyamide polyamine-epihalohydrin resin aqueous solution 2 was obtained. The degree of cationization by the colloid titration method was 4.2 meq / g · solids at pH 3, and 0.34 meq / g · solids at pH 10. After adding 135 g of water to 50.1 g of this polyamide polyamine-epihalohydrin resin aqueous solution 25, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, degree of etherification 0.75) The solution was added little by little over 10 minutes, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% with a ratio of polyamidepolyamine-epihalohydrin resin (B) and carboxymethylated cellulose of 50:50. This was designated as Paper Additive 2.

(Example 3) (Production Example of Paper Additive Containing Polyamide Polyamine Polyurea Resin (C) and Carboxymethylated Cellulose)
A 500 mL four-necked round bottom flask equipped with a thermometer, a condenser, a stirrer, and a nitrogen inlet tube was charged with 105.3 g (1.02 mol) of diethylenetriamine, and 146.1 g (1 mol) of adipic acid was added with stirring. The temperature was raised while removing the generated water out of the system, and the reaction was carried out at 170 ° C. for 3 hours. Next, the reaction solution was cooled to 130 ° C., 12 g (0.2 mol) of urea was added, and deammonia reaction was performed at the same temperature for 2 hours, and then water was gradually added to polyamide polyamine polyurea having a solid content of 50%. A resin aqueous solution 3 was obtained. The degree of cationization by the colloid titration method was 3.8 meq / g · solids at pH 3, and 0.01 meq / g · solids at pH 10. After adding 154.8 g of water to 330 g of this polyamide polyamine polyurea resin aqueous solution, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, degree of etherification 0.75) The solution was added little by little over 10 minutes, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% and a ratio of polyamide polyamine polyurea resin (C) to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 3.

(Example 4) (Production Example of Paper Additive Containing Polyamide Polyamine Polyurea-Epihalohydrin Resin (D) and Carboxymethylated Cellulose)
In another 500 ml four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a dropping funnel, 200 g of polyamide polyamine polyurea resin aqueous solution obtained in Example 1 (0.38 mol as amino group) was charged. After adding 5.5 g of epichlorohydrin (0.2 mol with respect to the amino group) at 20 ° C., the mixture was heated to 30 ° C. and kept at the same temperature for 10 minutes. Next, 122 g of water was added, heated to 50 ° C. and maintained at the same temperature until the viscosity reached 200 mPa · s (25 ° C.), then 30% sulfuric acid and water were added to adjust the pH to 6, and the solid content to 30 % Polyamidopolyamine polyurea-epihalohydrin resin aqueous solution 4 was obtained. The degree of cationization by the colloid titration method was 3.6 meq / g · solids at pH 3, and 0.15 meq / g · solids at pH 10. After adding 84.9 g of water to 50.1 g of this polyamide polyamine polyurea-epihalohydrin resin aqueous solution 4, carboxymethylated cellulose (the viscosity measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, the degree of etherification is 0.00. 75) 15 g was added little by little over 10 minutes, and the mixture was further stirred and mixed at room temperature for 2 hours. The ratio of polyamide polyamine polyurea-epihalohydrin resin (D) to carboxymethylated cellulose was 50%, and the solid content was 20%. An aqueous solution was obtained. This was designated as Paper Additive 4.

Example 5 (Production Example of Paper Additive Containing Polyamide Polyamine Resin (A) and Carboxymethylated Cellulose)
A polyamide polyamine resin aqueous solution 5 was obtained in the same manner as in Example 1 except that the ratio of diethylenetriamine and adipic acid in Example 1 was changed to 1: 0.5. The degree of cationization by the colloid titration method was 12.6 meq / g · solids at pH 3, and 0.01 meq / g · solids at pH 10. After adding 154.8 g of water to 530 g of this polyamide polyamine resin aqueous solution 530, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 10 mPa · s, etherification degree 0.5) is added for 10 minutes. The mixture was added little by little, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% and a ratio of polyamide polyamine resin (A) to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 5.

Example 6 (Production Example of Paper Additive Containing Polyamide Polyamine Resin (A) and Carboxymethylated Cellulose)
A polyamide polyamine resin aqueous solution 6 was obtained in the same manner as in Example 1 except that the ratio of diethylenetriamine and adipic acid in Example 1 was changed to 0.69: 1. The degree of cationization by the colloid titration method was 0.40 meq / g · solids at pH 3, and 0.01 meq / g · solids at pH 10. After adding 154.8 g of water to 630 g of this polyamide polyamine resin aqueous solution, 15 g of carboxymethylated cellulose (the viscosity measured with a B-type viscometer of 1% aqueous solution is 10 mPa · s, etherification degree 0.5) is added for 10 minutes. The mixture was added little by little, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% and a ratio of polyamide polyamine resin (A) to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 6.

Example 7 (Production Example of Paper Additive Containing Polyamide Polyamine-Epihalohydrin Resin (B) and Carboxymethylated Cellulose)
A polyamide polyamine-epihalohydrin resin aqueous solution 7 was obtained in the same manner as in Example 2 except that the polyamide polyamine resin aqueous solution in Example 2 was changed to the polyamide polyamine resin aqueous solution of Example 5. The degree of cationization by the colloid titration method was 10.8 meq / g · solids at pH 3 and 0.38 meq / g · solids at pH 10. After adding 135 g of water to 50.1 g of this polyamide polyamine-epihalohydrin resin aqueous solution 75, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, etherification degree 0.75) The solution was added little by little over 10 minutes, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% with a ratio of polyamidepolyamine-epihalohydrin resin (B) and carboxymethylated cellulose of 50:50. This was designated as Paper Additive 7.

Example 8 Production Example of Paper Additive Containing Polyamide Polyamine-Epihalohydrin Resin (B) and Carboxymethylated Cellulose
A polyamide polyamine-epihalohydrin resin aqueous solution 8 was obtained in the same manner as in Example 2 except that the polyamide polyamine resin aqueous solution in Example 2 was changed to the polyamide polyamine resin aqueous solution of Example 6. The degree of cationization by the colloid titration method was 0.34 meq / g · solids at pH 3, and 0.05 meq / g · solids at pH 10. After adding 135 g of water to 850.1 g of this polyamide polyamine-epihalohydrin resin aqueous solution 85, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, etherification degree 0.75) The solution was added little by little over 10 minutes, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% with a ratio of polyamidepolyamine-epihalohydrin resin (B) and carboxymethylated cellulose of 50:50. This was designated as Paper Additive 8.

(Examples 9 to 12) (Production Example of Paper Additive Containing Polyamide Polyamine Polyurea-Epihalohydrin Resin (D) and Carboxymethylated Cellulose)
An aqueous solution having a solid content of 20% in the same manner as in Example 4 except that the mixing ratio of the polyamide polyamine polyurea-epihalohydrin resin aqueous solution 4 and carboxymethylated cellulose in Example 4 as the solid content was changed to the ratio shown in Table 1. Got. These were designated as Paper Additives 9-12.

(Example 13) (Preparation example of paper additive containing polyamide polyamine polyurea-epihalohydrin resin (D) and urea phosphate esterified starch)
Polyamide polyamine polyurea-epihalohydrin resin (D) and Example 4 except that the carboxymethylated cellulose in Example 4 was changed to urea phosphate esterified starch (Matsutani Chemical Industry Co., Ltd. Neil Gum A55). An aqueous solution of 10% solids with a urea phosphate esterified starch ratio of 50:50 was obtained. These were designated as Paper Additive 13.

(Example 14) (Production Example of Paper Additive Containing Polyamide Polyamine Polyurea-Epihalohydrin Resin (D) and Carboxymethylated Starch)
In a flask equipped with a stirrer, a thermometer, and a reflux condenser, 45 g of water and 2.5 g of carboxymethyl starch (Matsutani Chemical Industry Co., Ltd. FC50) were taken and stirred and mixed at 90 ° C. for 20 minutes. Subsequently, 1.5 g of 5% ammonium persulfate aqueous solution was added, and the mixture was further stirred and mixed at 90 ° C. for 20 minutes. After cooling, the pH was adjusted to 7.0 with 25% sodium hydroxide to obtain a 5% aqueous solution of carboxymethylated starch. To this, 41.7 g of water and 8.3 g of the polyamide polyamine polyurea-epihalohydrin resin aqueous solution 4 of Example 4 were added, and then stirred and mixed at room temperature for 2 hours to obtain a polyamide polyamine polyurea-epihalohydrin resin (D). An aqueous solution having a carboxymethylated starch ratio of 50:50 and a solid content of 5% was obtained. This was designated as Paper Additive 14.

(Comparative Example 1) (Manufacture of additive for comparative example paper)
A polyamide polyamine-epihalohydrin resin aqueous solution 9 was obtained in the same manner as in Example 1 except that the amount of epichlorohydrin in Example 2 was changed to 1 mol with respect to the amino group. The degree of cationization by the colloid titration method was 3.4 meq / g · solids at pH 3, and 1.8 meq / g · solids at pH 10. After adding 135 g of water to 50.1 g of this polyamide polyamine-epihalohydrin resin aqueous solution 95, 15 g of carboxymethylated cellulose (measured with a B-type viscometer of 1% aqueous solution is 2 mPa · s, etherification degree 0.75) The solution was added little by little over 10 minutes, and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% with a ratio of polyamidepolyamine-epihalohydrin resin (B) and carboxymethylated cellulose of 50:50. This was designated as Paper Additive 15. The viscosity of the paper additive increased in several days and gelled.

(Comparative example 2) (Manufacture of additive for comparative example paper)
An alkaline sodium hypochlorite aqueous solution containing 30 g of sodium hypochlorite having an effective chlorine concentration of 12% and 7 g of caustic potash having an effective chlorine concentration of 12% is added dropwise with cooling and stirring to 240 g of an acrylamide polymer having a concentration of 15%. Thereafter, the reaction was carried out by maintaining the temperature at 25 ° C. for 60 minutes. After completion of the reaction, the reaction solution was adjusted to pH 4.5 with dilute hydrochloric acid to obtain a cation-modified acrylamide polymer by Hofmann decomposition reaction with a polymer concentration of 10%. After adding 135 g of water to 150 g of this cation-modified acrylamide polymer, 15 g of carboxymethylated cellulose (1% aqueous solution measured by B-type viscometer is 2 mPa · s, degree of etherification 0.75) is taken over 10 minutes. The solution was added little by little and further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 10% and a ratio of the cation-modified acrylamide polymer to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 16. The viscosity of the paper additive increased in several days and gelled.

(Comparative example 3) (Manufacture of additive for comparative example paper)
Water 401.22 g, 50% acrylamide aqueous solution 136.61 g (39.79 mol%), 76% acryloyloxyethyldimethylbenzylammonium chloride aqueous solution 40.58 g (4.50 mol%), 1% N, N ′ methylenebisacrylamide A mixture of 4.84 g (0.013 mol%) of an aqueous solution and 19.10 g (0.250 mol%) of an aqueous 5% sodium methallyl sulfonate solution was adjusted to pH 4.0 with an aqueous 20% sulfuric acid solution, and then nitrogen gas was introduced. After raising the temperature to 65 ° C. below, 6.64 g of 5% ammonium persulfate aqueous solution was added to initiate the reaction. Subsequently, 135.39 g of water separately charged at 85 ° C., 181.43 g (52.847 mol%) of 50% aqueous acrylamide solution, 7.85 g (2.50 mol%) itaconic acid, 5 A monomer aqueous solution consisting of 7.64 g (0.10 mol%) of a sodium methallylsulfonate aqueous solution was added dropwise over 30 minutes using a dropping funnel. After completion of the dropwise addition, the mixture was reacted at a reaction temperature of 90 ° C. for 2 hours to obtain an amphoteric acrylamide polymer having a solid content of 20%. After adding 180 g of water to 100 g of this amphoteric acrylamide polymer, 20 g of carboxymethylated cellulose (B-type viscometer measurement viscosity of 1% aqueous solution 2 mPa · s, etherification degree 0.75) is gradually added over 10 minutes. The mixture was further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 10% and a ratio of amphoteric acrylamide polymer to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 17. The viscosity of the paper additive increased in several days and gelled.

(Comparative example 4) (Manufacture of additive for comparative example paper)
In the same manner as in Example 1 except that polyvinylamine (manufactured by BASF: Catiofast VFH) was used instead of the polyamide polyamine resin aqueous solution in Example 1, the ratio of polyvinylamine to carboxymethylated cellulose was 50: A 50% 15% aqueous solution was obtained. This was designated as Paper Additive 18. The viscosity of the paper additive increased in several days and gelled.

(Comparative example 5) (Manufacture of additive for comparative example paper)
A flask equipped with a stirrer, a thermometer, and a reflux condenser was charged with 693.28 g of water, 166.96 g of cationized starch of tapioca raw material, and 58.92 g of 5% ammonium persulfate aqueous solution, and stirred and mixed at 90 ° C. for 30 minutes. Then, 80.0 g of water was added and cooled. Next, 25% aqueous sodium hydroxide solution was added to adjust the pH to 6.5 to obtain a 15% aqueous solution of cation-modified starch. After adding 85 g of water to 100 g of this cation-modified starch, 15 g of carboxymethylated cellulose (B-type viscometer measured viscosity of 1% aqueous solution 2 mPa · s, etherification degree 0.75) is gradually added over 10 minutes. The mixture was further stirred and mixed at room temperature for 2 hours to obtain an aqueous solution having a solid content of 15% and a ratio of cation-modified starch to carboxymethylated cellulose of 50:50. This was designated as Paper Additive 19.

(Comparative example 6) (Manufacture of additive for comparative example paper)
A flask equipped with a stirrer, thermometer, and reflux condenser was charged with 287.7 g of water, 169.6 g of 50% acrylamide aqueous solution, 19.0 g of 80% aqueous acrylic acid solution, and 0.9 g of sodium methallyl sulfonate, and introduced nitrogen gas. The temperature was raised to 60 ° C. Subsequently, 3.2 g of 5% ammonium persulfate aqueous solution was added to start the reaction. After about 30 minutes, the temperature in the reaction system rose to 80 ° C., and the reaction was further continued at a temperature of 80 ° C. for 2 hours. Thereafter, 24.8 g of water was added, and the pH was adjusted to 7 with a 20% aqueous sodium hydroxide solution to obtain an anionic acrylamide polymer having a solid content concentration of 20.2% and a viscosity of 4,000 cps. 180 g of this anionic acrylamide, 120 g of the polyamide polyamine polyurea-epihalohydrin resin 4 of Example 4 and 60 g of water are mixed and stirred at room temperature for 20 minutes, and the polyamide polyamine polyurea-epihalohydrin resin (D) An aqueous solution having a coalescence ratio of 50:50 and a solid content of 20% was obtained. This was designated as Paper Additive 20. The viscosity of the paper additive increased in several days and gelled.

(Comparative example 7) (Manufacture of additive for comparative example paper)
In the same manner as in Example 1 except that hydroxyethylated cellulose (manufactured by Daicel Chemical Industries: HEC Daicel SP 400) was used instead of the carboxymethylated starch in Example 14, a polyamide polyamine polyurea-epihalohydrin resin ( An aqueous solution having a solid content of 5% and a ratio of D) to hydroxyethylated cellulose of 50:50 was obtained.
This was designated as Paper Additive 21.

(Example 15)
Hardwood bleached sulfite pulp (hereinafter abbreviated as LBKP) was adjusted to CSF (Canadian Standard Freeness) 405, and the paper additive 1 described in Example 1 was used on paper with a concentration of 2.4%. It added so that it might become 0.2% with respect to a raw material. After stirring, paper was made with a square sheet machine to obtain hand-made papers having a basis weight of 40 g / m ² and 60 g / m ² . The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then measured for tear length, Clark stiffness, and water disintegration by the following methods. In addition, the addition rate of the said additive 1 for paper is solid content weight ratio with respect to a pulp absolute dry weight. The measurement results are shown in Table 2.

Breaking length: JIS P8113 A tensile property test method, measured with paper having a basis weight of 40 g / m ² .
Clark stiffness: JIS P8143 Clark stiffness test, measured with paper having a basis weight of 60 g / m ² .
Water disintegration: JIS P4501 Measured with a paper having a looseness test and a basis weight of 40 g / m ² .

(Examples 16 to 28)
Handsheets having a basis weight of 40 g / m ² and 60 g / m ^{2 in} the same manner as in Example 15 except that the paper additive 1 used in Example 15 was replaced with the paper additive of Examples 2 to 14. I got paper. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. The measurement results are shown in Table 2.

(Comparative Examples 8-14)
Handsheets having a basis weight of 40 g / m ² and 60 g / m ^{2 in} the same manner as in Example 15 except that the paper additive 1 used in Example 15 was replaced with the paper additive of Comparative Examples 1 to 7. I got paper. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. The measurement results are shown in Table 2.

(Comparative Example 15)
Instead of the paper additive 1 used in Example 15, the polyamide polyamine resin aqueous solution 1 of Example 1 was added so as to be 0.1% based on the stock, and then carboxymethylated cellulose (1% 40 g basis weight in the same manner as in Example 15 except that the viscosity measured by a B-type viscometer of the aqueous solution was 10 mPa · s, and the degree of etherification was 0.5) with respect to the stock. / M ² and 60 g / m ² handmade paper were obtained. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. The measurement results are shown in Table 2.

(Comparative Examples 16-18)
The polyamide polyamine resin aqueous solution 1 used in Comparative Example 15 was changed to that shown in Table 2, and carboxymethylated cellulose (1% aqueous solution measured with a B-type viscometer was 10 mPa · s, etherification degree 0.5). The basis weight was 40 g / m ² and 60 g / m in the same manner as in Comparative Example 15 except that carboxymethylated cellulose (B-type viscometer measurement viscosity of 1% aqueous solution was 2 mPa · s, etherification degree 0.75) was used. ^Two hand-made papers were obtained. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. The measurement results are shown in Table 2.

Abbreviations in Table 2 (Note 1) Not added after mixing to the stock, but added separately.

(Example 29)
Hardwood bleached sulfite pulp (hereinafter abbreviated as LBKP) was adjusted to CSF (Canadian Standard Freeness) 390, and the paper additive 1 described in Example 1 was used on paper with a concentration of 2.4%. After adding so that it might be 0.1% with respect to the material, 0.2% of the paper softener described in Table 3 was added. After stirring, paper was made with a square sheet machine to obtain hand-made papers having a basis weight of 40 g / m ² and 60 g / m ² . The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. Table 3 shows the measurement results.

(Examples 30 to 38, Comparative Examples 15 to 18)
Handsheets with basis weights of 40 g / m ² and 60 g / m ^{2 in} the same manner as in Example 29 except that the paper additives and paper softeners used in Example 29 were changed to those shown in Table 3. I got paper. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. Table 3 shows the measurement results.

(Comparative Examples 19-24)
Without the use of paper additives used in Example 29, except for changing the paper softener to those described in Table 3 in the same manner as in Example 29, basis weight 40 g / m ² and 60 g / m ² Hand-made paper was obtained. The obtained handmade paper was conditioned for 24 hours under conditions of 23 ° C. and 50% humidity, and then the tear length, Clark stiffness, and water disintegration property were measured in the same manner as in Example 15. Table 3 shows the measurement results.

Explanation of abbreviations in Table 3 (Note 1) EO indicates ethylene oxide, PO indicates propylene oxide, and the numbers in parentheses indicate average addition amounts (moles).
(Note 2) The alkyl group is a mixture of 12 to 18 carbon atoms, and the main component is a lauryl group.
(Note 3) Mixture of oleic acid-EO (4) PO (12) -oleyl alcohol and dioleyldimethylammonium chloride (solid content ratio 90:10)

  As is apparent from the results shown in Table 2, the paper additive in the present invention has a small adverse effect on the water decomposability of the paper and exhibits an excellent paper strength enhancing effect without impairing the flexibility of the paper. Can do. Further, as is apparent from the results shown in Table 3, the paper additive in the present invention has little adverse effect on the water decomposability of the paper even when used in combination with the paper softener and impairs the paper flexibility. In addition, an excellent paper strength enhancing effect can be achieved.

Claims (4)

Containing a carboxymethylated starch and / or carboxymethyl cellulose is a water-soluble polysaccharide having at least one cationic resin and an anionic group selected from the following resins (C) ~ (D), and a cationic resin An additive for paper , wherein the mixing ratio in solid content with the water-soluble polysaccharide having an anionic group is 90/10 to 10/90 .
( C) Polyamide polyamine polyurea resin obtained by heat condensation of dibasic carboxylic acid compound, polyalkylene polyamine compound and urea compound (D) Heat condensation of dibasic carboxylic acid compound, polyalkylene polyamine compound and urea compound Polyamide polyamine polyurea resin obtained by reacting polyamide polyamine polyurea resin with 0.5 mol or less of epihalohydrin with respect to 1 mol of amino group in polyamide polyamine polyurea resin The cationization degree at pH 3 of at least one cationic resin selected from the resins ( C ) to (D) is at least 1.5 meq / g · solids, and the cationization degree at pH 10 is at most 0.5 meq / The paper additive according to claim 1, wherein the additive is g · solid. A papermaking method, wherein the paper additive according to claim 1 or 2 is added to a pulp slurry for papermaking. A papermaking method, wherein the paper additive and the paper softener according to claim 1 or 2 are added to a pulp slurry to make a paper.