JPH11200290A - Surface coating agent for papermaking and its use - Google Patents

Abstract

(57) [Problem] To provide a polymer effective for use in base paper for inkjet coating. SOLUTION: N-vinylcarboxylic acid amide 35 to 10
A monomer containing 0 mol% and 0 to 65 mol% of acrylonitrile is (co) polymerized and then hydrolyzed, and benzyl chloride is added to the water-soluble polymer obtained in an amount of 10 to 10% based on the charged amount of N-vinylcarboxylic acid amide. By coating a cationic polymer characterized by a reaction of 100 mol% on paper, a coated base paper for inkjet can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a novel cationic polymer useful as a papermaking agent, comprising a novel cationic polymer having a vinylamine structural unit or a vinylamidine structural unit in the main chain. And a coating agent used for coating base paper.

[0002]

2. Description of the Related Art Conventionally, a method of producing polyvinylamine by Hoffman decomposition of polyacrylamide is known. Further, it can be produced by hydrolyzing poly N-vinyl carboxylic acid amide obtained by polymerizing N-vinyl carboxylic acid amide (JP-A-58-23809).
Further, a water-soluble polymer having a vinylamino group can be produced by hydrolyzing a copolymer of N-vinylcarboxylic acid amide and vinyl acetate (Japanese Patent Application Laid-Open No. Sho 62-74902).
No.). N-vinyl carboxylic acid amide and acrylonitrile are copolymerized, and the copolymer is hydrolyzed,
Further, a water-soluble polymer which has been denatured at high temperature and converted into an amidine has also been proposed (JP-A-63-165412, JP-A-6-123096). When these known agents are used as coating agents and the like, their effects are still insufficient.

[0003]

An object of the present invention is to provide a polymer flocculant comprising a novel cationic water-soluble polymer which has not been known so far.

[0004]

Means for Solving the Problems The present inventors reacted benzyl chloride with a cationic water-soluble polymer obtained by hydrolyzing a (co) polymer of a monomer containing N-vinyl carboxylic acid amide. The inventors have found that the resulting water-soluble polymer is effective as a surface coating agent for paper for ink jet recording, and have accomplished the present invention.

The invention of claim 1 of the present invention relates to a water-soluble polymer obtained by copolymerizing a monomer containing 35 to 100 mol% of N-vinylcarboxylic acid amide and 0 to 65 mol% of acrylonitrile, and then hydrolyzing it. Benzyl chloride was added to the polymer in an amount of 10 to 10% based on the amount of N-vinylcarboxylic acid amide charged.
A surface coating agent for papermaking, characterized by reacting 100 mol%.

The invention of claim 2 of the present invention is characterized in that the water-soluble polymer forming the surface coating agent for the papermaking paper has an intrinsic viscosity of 0.1 to 10 dl / g in 1N saline. The surface coating agent for papermaking according to claim 1.

The invention of claim 3 of the present invention is characterized in that the colloid equivalent value at pH 3.0 of the water-soluble polymer forming the surface coating agent of the paper is 3.0 meq / g or more. The surface coating agent for papermaking according to claim 1 or claim 2.

According to a fourth aspect of the present invention, there is provided a method for producing an ink jet recording paper, comprising applying the surface coating agent of the paper according to any one of the first to third aspects to the surface of a coated base paper. It is.

[0009]

DETAILED DESCRIPTION OF THE INVENTION A first limitation of the present invention is that it is obtained by copolymerizing a monomer containing 35 to 100 mol% of N-vinyl carboxylic acid amide and 0 to 65 mol% of acrylonitrile, followed by hydrolysis. Benzyl chloride is added to the water-soluble polymer in an amount of 1 to the charged amount of N-vinyl carboxylic acid amide.
A surface coating agent for papermaking, characterized in that it is reacted by 0 to 100 mol%. A second limitation of the present invention is claim 1
The surface-coating agent for papermaking according to the above, wherein the water-soluble polymer forming the surface-coating material for papermaking has an intrinsic viscosity in 0.1 N saline of 0.1 to 10 dl / g. I do. A third limitation of the present invention is a colloid at pH 3.0 of the water-soluble polymer forming the surface coating agent of the papermaking according to claim 1 or 2. The equivalent value is 3.0 meq / g or more. A fourth limitation of the present invention is that in the surface coating agent for papermaking according to claims 1 to 3, the surface coating agent for papermaking according to claims 1 to 3 is applied to the surface of the base paper. This is a method for producing an ink jet recording paper, characterized in that it is coated on a substrate.

The hydrolyzate of the N-vinylcarboxylic acid amide (co) polymer produces an amino group or an amidine group and reacts with benzyl chloride, and the amino group or amidine group has a cationic property while reducing active hydrogen by one. However, hydrophobicity is caused by the benzyl group at the terminal of the reactant. As a result, a water-soluble polymer having the most appropriate range of adsorption and ionic strength is provided. In some cases, a carboxyl group is formed as a by-product in the hydrolysis of the acrylonitrile copolymer, but if the amount is small, the effect is not affected.

It is desirable that the water-soluble polymer of the present invention has an intrinsic viscosity in 1N saline in the range of 0.1 to 10 dl / g. Particularly preferably, 0.2 to 3 dl / g is particularly preferably used as a surface coating agent.

The colloid equivalent value of the water-soluble polymer of the present invention is not less than 3.0 meq / g at pH 3.0, and below this, a satisfactory effect cannot be exhibited in various uses of the present invention.

[0013] The invention of claim 3 of the present invention relates to a surface coating agent for papermaking as a specific use of the above water-soluble polymer. The present invention relates to other coating agents such as cationic starch and oxidized starch. Water-soluble polymers such as starch and polyvinyl alcohol, and latex, or coating pigments such as colloidal silica, talc, kaolin clay, and calcium carbonate can be used in combination. The addition amount of these coating agents is usually 0.1.
05 to 10 g / m ^2, preferably 0.2 to 5 g / m ² . The base paper for coating is not particularly limited, and can be applied to base papers such as coated base paper of acid paper and neutral paper, newsprint, PPC paper and the like. A water-soluble polymer of the present invention alone or mixed with another coating agent is coated on a coating base paper with a size press, a gate roll coater, a blade coater, a calender, or the like, and the surface is coated. It can be.

The invention of claim 4 of the present invention relates to a surface coating agent for papermaking as a specific application of the above water-soluble polymer, characterized in that the product of the present invention is applied to the surface of a coated base paper. Is a method for producing an ink jet recording paper. The present invention not only improves the printability of the coated base paper as described above, but also combines with an anionic water-soluble ink as an inkjet recording paper to make it water-insoluble, suppresses penetration into the paper, and performs inkjet printing. Maintains a vivid color tone in the expression of the color.

[0015]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist.

(Synthesis Examples 1-2) Stirrer, nitrogen inlet tube,
In a 300 ml four-necked flask equipped with a condenser and a thermometer, 40.0 g of a monomer having the composition shown in Table 1 and deionized water 14 were added.
3.0 g, 1% aqueous solution of hydroxylamine hydrochloride 7.0
g was added. After passing nitrogen gas under ice cooling, 50 ° C
To 2,2'-azobis-2-amidinopropane.
10.0 g of a 2% aqueous solution of dihydrochloride was added, and the mixture was maintained at 50 ° C. for 6 hours with stirring at 300 rpm. The whole amount of the polymer was added to acetone to precipitate a polymer, which was dried under vacuum to obtain a solid granular polymer. Next, 25 g of the solid particulate polymer and 100 g of demineralized water were placed in a 200 ml three-necked flask equipped with a stirrer, a cooler and a thermometer,
8 g of a 10% aqueous solution of hydroxylamine and 110 mol% of caustic soda based on formyl group are added, and the mixture is reacted at 60 ° C. for 3 hours with stirring. Then, 70 mol% of benzyl chloride based on formyl group is added and stirred. The reaction was carried out at 60 ° C. for 3 hours. The obtained reaction product solution was dropped into acetone to cause precipitation, and this was dried under vacuum to obtain a solid particulate polymer. The colloid equivalent value and the intrinsic viscosity were measured by a conventional method. The results are shown in Table 1.

(Comparative Synthesis Examples 1-4) Samples prepared by performing the same operations as in the Synthesis Examples without using benzyl chloride were prepared. The results are shown in Table 1.

[0018]

[Table-1]

[Effect test-1] Coating solution (6.8 g of fine powdered silica, PVA117 (manufactured by Kuraray Co., Ltd.) was used as a support, using a high-quality paper having a basis weight of 70 g / m ² and a Steckigt sizing degree of 25 seconds as a support.
2.7 g, 0.5 g of the polymer of this example and 40 g of water
Was mixed with a coating rod at a solid content of 5.0 g / m ² on one side to obtain a coated paper. After color printing of this coated paper, the water resistance and lightfastness of the print were measured as follows. Color printing is provided by Canon Inc.
Solid printing was performed for each color of magenta (M), cyan (C), yellow (Y), and black (BL) using a color bubble jet printer manufactured by BJC600. The results are shown in Table-2. (Water resistance) The solid printed image was immersed in running water of 3 liter / min for 10 minutes, and the image density before and after the test was evaluated on a 5-point scale. <Judgment> A: No change B: Color slightly exudes. C: Discoloration is recognized. D: Large discoloration. E: Almost decolorization. (Light fastness) The solid printed image is 24
Irradiation was performed for a period of time, and the image density before and after the irradiation was evaluated in four stages. <Judgment> A: No change B: Slight fading. C: Fading. D: Extremely fading.

[0020]

[Table-2]

[0021]

According to the present invention, a benzyl chloride reaction product of an N vinyl carboxylic acid amide (co) polymer hydrolyzate is used as an ink-jet recording sheet for the N vinyl carboxylic acid amide (co) polymer hydrolyzate that does not react with the benzyl chloride. It is difficult to guess from a conventionally known technique, which exhibits an excellent effect as a surface coating agent for a paper made for production and has high product stability.

[Table 1]

[Table 2]

Claims (4)

[Claims] 1. N-vinylcarboxylic acid amide 35 to 10
A monomer containing 0 mol% and 0 to 65 mol% of acrylonitrile is (co) polymerized and then hydrolyzed, and benzyl chloride is added to the water-soluble polymer obtained in an amount of 10 to 10% based on the charged amount of N-vinylcarboxylic acid amide. A surface coating agent for paper made by reacting 100 mol%. 2. The water-soluble polymer forming the surface coating agent of the papermaking paper has an intrinsic viscosity of 0.1 to 1 in 1N saline.
The surface coating agent for papermaking according to claim 1, wherein the surface coating agent is 10 dl / g. 3. A colloid equivalent value at pH 3.0 of a water-soluble polymer forming a surface coating agent of the paper making is 3.0.
The surface coating agent for papermaking according to claim 1 or 2, wherein the surface coating agent is at least meq / g. 4. A method for producing an ink jet recording paper, comprising applying the surface coating agent of the paper according to claim 1 to the surface of a coated base paper.