JP3214119B2 - Coating composition for paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper coating composition, and more particularly to a paper coating composition capable of imparting excellent printability and printing effect to paper. What you want to do.

[0002] The term "paper" as used herein has a broad meaning, and includes paper and paperboard in a narrow sense.

[0003]

2. Description of the Related Art Coated paper obtained by applying a coating composition mainly composed of a pigment and an aqueous binder to paper, and subjecting the coated paper to necessary steps such as drying and calendering is characterized by its excellent printing effect. Therefore, it is widely used in commercial prints, magazines and books, etc., but with the sophistication of quality requirements and the speeding up of printing, efforts to improve the quality of coated papers are still ongoing. Particularly in offset printing, which accounts for the majority of printing, improvement and improvement of ink receptivity under the influence of shampooing water and water resistance of wet topics and wet labs are important issues in the industry.

Conventionally, to solve such problems, a melamine-formaldehyde resin, a urea-formaldehyde resin, or a polyamide polyurea-formaldehyde resin, for example, JP-B-44-11667 and JP-B-59-32597.
There is known a method of adding a water-proofing agent, a printability improving agent, and the like as described in Japanese Patent Application Laid-Open Publication No. H11-163,028.

[0005] However, these conventional water-proofing agents and printability-improving agents all have effective properties, but on the other hand, serious disadvantages or insufficient effects are recognized in some of the properties, so that they are practically used. It was not always satisfactory.

For example, aminoplast resins such as melamine-formaldehyde resin and urea-formaldehyde resin not only generate a large amount of formaldehyde at the time of work or from coated paper, but also have almost the effect of improving ink receptivity. However, there is a problem that when the pH of the coating composition is increased, the water-resistant effect is hardly exhibited.

[0007] Polyamide polyurea-formaldehyde resins are effective not only for improving the water resistance but also for improving the ink receptivity, but their degree of improvement is not always sufficient to meet the recent demand for advanced coated paper quality. I wanted something good. Therefore, efforts have been made to further improve the quality. For example, JP-A-62-125093, JP-A-4-82996, and JP-A-4-100997 have further improved paper coating. An engineered composition is disclosed. However, as the demands for the quality of coated paper have become higher thereafter, higher performance has been required.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper coating composition which can impart high water resistance and ink receptivity to paper.

The present inventors have conducted intensive studies to solve such problems, and as a result, have found that a paper coating composition containing a specific water-soluble resin exhibits excellent performance. completed.

[0010]

That is, the present invention relates to a method for producing a pigment comprising (I) a pigment, (II) an aqueous binder, and (III) substantially the following compounds (a) and (b):
Water-soluble resin (A) obtained by reacting the following components: (a) methylamine, ethylamine, propylamine,
Tylamine, pentylamine, hexylamine , octyl
Ruamine, isopropylamine , isobutylamine, 2
- ethylhexylamine, cyclo hexylamine, Ami
Nomethylcyclohexane, ethanolamine , 2-pro
Panoruamin, glycine, aromatic primary amines, ethyl
Rangeamine, propylenediamine, hexamethylenedi
Amine , bisaminomethylcyclohexane, phenylene
Diamine, tolylenediamine, xylylenediamine,
That is selected from Riamin compound of at least one primary and /
Another object of the present invention is to provide a paper coating composition comprising an amine compound having a secondary amino group (b), a di- or poly-glycidyl ether .

In the present invention, an amine compound (a) having a primary or secondary amino group, which is a raw material of the water-soluble resin (A),
Various types can be used, and examples thereof include aliphatic primary amines, aromatic primary amines, secondary amines, diamines, and polyamines.

Examples of the aliphatic primary amines include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, octylamine, isopropylamine, isobutylamine, 2-ethylhexylamine, cyclohexylamine, aminomethylcyclohexane, Examples include ethanolamine, 2-propanolamine, and glycine. Examples of the aromatic primary amines include aniline, toluidine, benzylamine, naphthylamine, m-aminophenol,
-Aminopyridine and the like. Secondary amines include, for example, dimethylamine, diethylamine, dipropylamine, pyrrolidine, piperidine and the like.

The diamines include, for example, ethylenediamine, propylenediamine, hexamethylenediamine,
Bisaminomethylcyclohexane, phenylenediamine, tolylenediamine, xylylenediamine and the like can be mentioned. Examples of the polyamines include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, iminobispropylamine, and 3-azahexane-1,6-diamine.

The amine compound (a) is exemplified by ethanolamine, 2-propanolamine, glycine, m-
Like an aminophenol, it may have a functional group that is inactive in a reaction with an epoxy compound described below.

The amine compound (a) having a primary or secondary amino group can be used alone or as a mixture of two or more. Of these, primary amines are preferably used for the purpose of the present invention in view of the degree of polymerization and the like. Further, from the viewpoint of coloring, primary amines having no nitrogen directly bonded to the aromatic ring are more preferable.

Epoxy compound (b) as another raw material
Is a compound having at least two epoxy groups in a molecule, and can be a diepoxy compound having two epoxy groups in a molecule and a polyepoxy compound having three or more epoxy groups in a molecule.

For example, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether,
Neopentyl glycol diglycidyl ether, cyclohexane dimethanol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, resorcin diglycidyl ether, xylylene diol diglycidyl ether, bisphenol A diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl Ethers and diglycidyl ethers such as glycerol diglycidyl ether can be used.

Glycerol triglycidyl ether, trimethylolpropane triglycidyl ether,
Polyglycidyl ethers such as pentaerythritol tetraglycidyl ether, sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, triglycidyl tris (2-hydroxyethyl) isocyanurate can be used.

[0019] Further, diglycidyl adipate, diglycidyl hexahydrophthalate, diglycidyl esters such as diglycidyl phthalate, which compounds of polyglycidyl esters such as triglycidyl trimellitate also encompassed.

Each of these epoxy compounds (b) can be used alone or as a mixture of two or more. The above-mentioned glycidyl ethers and glycidyl esters are usually synthesized by reacting the corresponding polyol or polycarboxylic acid with epihalohydrins, and the reaction product can be used as it is without purification.

Among these epoxy compounds, di- or poly-glycidyl ethers are preferably used because they are less susceptible to hydrolysis and the like and have high reactivity. Diglycidyl ethers are particularly preferable.

The water-soluble resin (A) used in the present invention is usually an amine compound (a) having a primary or secondary amino group and an epoxy compound (a) having at least two epoxy groups in a molecule. b) a monoepoxy compound having no functional group such as ammonia, tertiary amines such as trimethylamine and dimethylbenzylamine, and other functional groups such as ethylene oxide and styrene oxide for the purpose of controlling the degree of polymerization and the like. Can be used within a range that does not affect the performance.

As for the water-soluble resin (A) in the present invention, other compounds may be used as long as the performance is not affected, but the components substantially consisting of the following two compounds are reacted. It is obtained by doing. (a) an amine compound having a primary or secondary amino group, and (b) an epoxy compound having at least two epoxy groups in a molecule.

The reaction between the two is usually performed at about 10 to 100 ° C.
Preferably, it is performed at a temperature of about 30 to 70 ° C. for about 0.5 to 10 hours. The amount of both components used is the amine compound (a)
Epoxy compound to 1 mol of amine active hydrogen
It is preferable that the epoxy group in (b) be in the range of 0.5 to 1.5 mol, more preferably the epoxy compound
(b) The content of the epoxy group is adjusted to 0.7 to 1.2 mol.

This reaction may be carried out without a solvent or in a solvent. Examples of the solvent that can be used include water, methanol, acetone, and the like. Although this reaction proceeds without a catalyst, it can be carried out in the presence of a catalyst. Examples of catalysts that can be used include acid catalysts such as hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, and acetic acid, and Lewis acid catalysts such as aluminum chloride, magnesium chloride, and zinc borofluoride.

The reaction can be carried out by mixing the two components at the same time, but it is also preferable to prepare one of them first and then gradually add the other. For example, a method of adding an epoxy compound (b) to an amine compound (a) having a primary or secondary amino group is as follows.
It is particularly preferable for controlling the degree of polymerization.

In the present invention, the resin containing the water-soluble resin (A) thus obtained is used as the resin component (III),
A paper coating composition is prepared by blending the pigment (I) and the aqueous binder (II).

The pigment (I) which is a component of the paper coating composition in the present invention may be any of those conventionally used in paper coating, and white inorganic pigments and white organic pigments may be used. Examples of the white inorganic pigment include kaolin, talc, calcium carbonate (heavy or light), aluminum hydroxide, satin white, titanium oxide and the like. As the white organic pigment, for example, polystyrene,
Melamine-formaldehyde resin, urea-formaldehyde resin and the like can be mentioned. These pigments can be used alone or in combination of two or more. Still further, a colored inorganic or organic pigment may be used in combination.

The aqueous binder (II), which is another component, may be any of those conventionally used in paper coating, and a water-soluble binder or a water-emulsifying binder may be used. Examples of the water-soluble binder include unmodified or modified starches including oxidized starch and phosphorylated ester, polyvinyl alcohol, water-soluble proteins including casein and gelatin, denaturation including carboxymethyl cellulose. And celluloses. Examples of the water-emulsifying binder include, for example, a styrene-butadiene resin, a vinyl acetate resin, an ethylene-vinyl acetate resin, and a methyl methacrylate resin. These aqueous binders can be used alone or in combination of two or more.

In preparing the paper coating composition,
The composition ratio of each of the pigment (I) and the aqueous binder (II) is determined depending on the use and purpose, and there is no particular difference from compositions generally used in the art. The preferred composition ratio of both is about 5 to 200 parts by weight, more preferably about 10 to 50 parts by weight, based on 100 parts by weight of the pigment (I). Resin component (III)
Is preferably 0.05 to 100 parts by weight of the pigment (I).
About 5 parts by weight, more preferably about 0.1 to 2 parts by weight.

The resin component (III) is generally added and mixed at the time of preparing a paper coating composition. However, the resin component (III) is previously added to and mixed with a pigment slurry or an aqueous binder, and then mixed with the remaining components. Even when the aspect is adopted, the effects of the present invention can be achieved.

In the paper coating composition of the present invention, other components such as a dispersant, a viscosity / fluidity regulator, an antifoaming agent, a preservative, a lubricant, a water retention agent, a dye / colored pigment, etc. And the like can be added as necessary.

The paper coating composition of the present invention can be prepared by a conventionally known method, for example, by using various known coaters such as a blade coater, an air knife coater, a bar coater, a size press coater, a gate roll coater, and a cast coater. Is applied to a paper substrate. Thereafter, necessary drying is performed, and if necessary, a smoothing treatment is performed with a super calender or the like, whereby a coated paper can be manufactured.

[0034]

The present invention will be described in more detail with reference to the following Reference Examples and Examples, which should not be construed as limiting the present invention. The percentages and parts in the examples are on a weight basis unless otherwise specified. The viscosity is a value at 25 ° C.

Reference Example 1 In a four-necked flask equipped with a thermometer, a reflux condenser and a stirring rod, 176.5 g of water and 73.1 g (1.0 g of butylamine) were placed.
Mol), and 191.6 g (1.1 mol) of ethylene glycol diglycidyl ether were added dropwise.
The reaction was performed at 0 to 60 ° C for 2 hours. Then, the pH was adjusted to 9.0 and the concentration was 40% with sulfuric acid and water to obtain an aqueous solution of a water-soluble resin having a viscosity of 55 cps.

Reference Example 2 In the same apparatus as used in Reference Example 1, 176.5 g of water and 94.2 g (1.0 mol) of cyclohexylamine were charged, and ethylene glycol diglycidyl ether 1 was further added.
After dropping 65.5 g (0.95 mol), 40-50 ° C.
For 2 hours. Then, add hydrochloric acid and water to pH
After adjusting the concentration to 8.5 and the concentration to 40%, an aqueous solution of a water-soluble resin having a viscosity of 50 cps was obtained.

Reference Example 3 In the same apparatus as used in Reference Example 1, 181.5 g of water and 61.1 g (1.0 mol) of monoethanolamine were charged, and resorcin diglycidyl ether 211.1 was further added.
g (0.95 mol) was added dropwise, and the mixture was reacted at 40 to 50 ° C for 2 hours. Thereafter, the pH was adjusted to 6.0 and the concentration was 40% with hydrochloric acid and water to obtain an aqueous solution of a water-soluble resin having a viscosity of 610 cps.

COMPARATIVE REFERENCE EXAMPLE 1 146.2 g (1.0 mol) of triethylenetetramine was placed in a four-necked flask equipped with a thermometer, a reflux condenser and a stirring rod.
And 30.0 g (0.5 mol) of urea, and the internal temperature was 140
The mixture was heated at -160 ° C for 3.5 hours to carry out a deammonification reaction. Thereafter, 73.1 g (0.5 mol) of adipic acid was charged, and the dehydration amidation reaction was carried out for 5 hours while maintaining the internal temperature at 150 to 160 ° C. Next, the internal temperature was lowered to 130 ° C, 120.1 g (2.0 mol) of urea was charged, and a deammonification reaction was carried out at 120 to 130 ° C for 2 hours. Then 284.5 water
g was added to obtain a resin aqueous solution. Further, 60.9 g (0.75 mol) of 37% formalin was charged, the pH of the system was adjusted to 4 to 5 with 70% sulfuric acid, and the mixture was reacted at an internal temperature of 70 ° C for 4 hours. Thereafter, the pH was adjusted to 6.5 with an aqueous sodium hydroxide solution to obtain a resin aqueous solution having a concentration of 50% and a viscosity of 140 cps.

Example Using the aqueous solutions of the water-soluble resins obtained in Reference Examples 1 to 3 and Comparative Reference Example 1, paper coating compositions having the formulations shown in Table 1 were prepared.

[0040]

[Table 1] ^{* 1} Ultra White 90: Clay manufactured by Engel Hard Minerals, Inc. ^{* 2} Carvital 90: Calcium carbonate manufactured by Fuji Kaolin Co., Ltd. ^{* 3} Sumireze Resin DS-10: Polyacrylic acid pigment dispersant manufactured by Sumitomo Chemical Co., Ltd. ^{* 4} SN-307: Styrene butadiene latex manufactured by Sumitomo Dow Co., Ltd. ^{* 5} Oji Ace A: Oxidized starch manufactured by Oji National Co., Ltd. ^{* 6 The} mixing ratio is represented by the weight of solid content.

The prepared paper coating composition had a total solid content of 6%.
Water and a 10% aqueous sodium hydroxide solution were used to adjust the pH to 0% and the pH to about 9.0. The physical properties of this composition were measured as follows, and the results are shown in Table 2.

Physical properties of coating composition (a) pH glass electrode type hydrogen ion concentration meter [Toa Denpa Kogyo KK
The pH of the coating composition immediately after preparation was measured at 25 ° C.

(B) Viscosity: Using a B-type viscometer (BL type, manufactured by Tokyo Keiki Co., Ltd.)
The viscosity of the coating composition immediately after preparation was measured at 25 ° C. and rpm.

The coating composition was applied to one or both sides of high quality paper having a basis weight of 80 g / m ² by using a wire rod so that the coating amount was 14 g / m ² . Immediately after the application, the resultant was dried with hot air at 120 ° C. for 30 seconds, then conditioned overnight at a temperature of 20 ° C. and a relative humidity of 65%, and further subjected to a supercalender treatment twice at a temperature of 60 ° C. and a linear pressure of 60 kg / cm. Thus, a coated paper was obtained.

The coated paper thus obtained was subjected to tests for water resistance and ink acceptability. The test results are shown in Table 2. The test method is as follows.

Water resistance (A) Wet rub method (WR method) Approximately 0.1 ml of ion-exchanged water was dropped on the coated surface and rubbed 7 times with a fingertip to transfer the eluted material to black paper and eluted The amount was determined visually. The judgment criteria were as follows. Water resistance (poor) 1-5 (excellent)

(B) Wet topic method (WP method) Using a RI tester (manufactured by Meisho Seisakusho), the coated surface was wetted with a water supply roll and then printed, and the peeling state was visually observed and judged. The judgment criteria were as follows. Water resistance (poor) 1-5 (excellent)

Ink Acceptability (A) Method A Using an RI tester, the coated surface was wetted with a water supply roll and then printed, and the ink acceptability was visually observed and judged. The judgment criteria were as follows. Ink acceptability (poor) 1-5 (excellent)

(B) Method B Using an RI tester, printing was performed while water was kneaded into the ink, and the ink receptivity was visually observed and judged. The judgment criteria were as follows. Ink acceptability (poor) 1-5 (excellent)

[0050]

[Table 2]

[0051]

The coated paper obtained by using the paper coating composition of the present invention has various excellent and effective properties such as excellent ink acceptability and water resistance and no generation of formaldehyde odor. Have.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-333697 (JP, A) JP-A-4-263696 (JP, A) JP-A-2-221498 (JP, A) JP-A-61- 252396 (JP, A) JP-A-6-57694 (JP, A) JP-A-6-158593 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D21H 19/00-19 / 84

Claims (3)

(57) [Claims] (1) a pigment, (II) an aqueous binder, and (III) substantially a compound of the following (a) and (b):
Water-soluble resin (A) obtained by reacting the following components: (a) methylamine, ethylamine, propylamine,
Tylamine, pentylamine, hexylamine , octyl
Ruamine, isopropylamine , isobutylamine, 2
- ethylhexylamine, cyclo hexylamine, Ami
Nomethylcyclohexane, ethanolamine , 2-pro
Panoruamin, glycine, aromatic primary amines, ethyl
Rangeamine, propylenediamine, hexamethylenedi
Amine , bisaminomethylcyclohexane, phenylene
Diamine, tolylenediamine, xylylenediamine,
That is selected from Riamin compound of at least one primary and /
Or a coating composition for paper, which comprises an amine compound having a secondary amino group (b) di- or poly-glycidyl ethers . 2. The method according to claim 1, wherein the water-soluble resin (A) is an amine compound (a).
1 mole of amine active hydrogen in epoxy compound (b)
Of the epoxy groups in a ratio of 0.5 to 1.5 mol
The paper coating composition according to claim 1, which is obtained. 3. The coating composition for paper according to claim 1 or 2.
Water resistance and ink resistance of coated paper characterized by using
How to improve acceptance.