JPS60134096A - Production of coated paper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing coated paper.

(Prior art) Conventionally, in the production of coated paper,
-, +l〃-)l→-Ichi Elementary School, 5 no 1 no-shi 1 ee I 4
5 uses natural binders such as casein,
Water-based coating colors consisting of these natural binders, fillers and fluorescent brighteners have been applied to the paper surface, but these natural products have the disadvantage that their availability and quality are not always stable. ing. On the other hand, with the development of synthetic polymer chemistry, synthetic polymer binders that replace these natural binders have begun to be supplied at a lower cost than natural binders, but if only synthetic polymer binders are used without using any natural products as binders, Since the action of the fluorescent brightener used in combination is significantly impaired and the effect is almost no longer exhibited, it is necessary to use 10 to 50 natural binders in the binder. (Objective of the Invention) The present invention The object of the present invention is to provide a method for producing a coach, Dopeno 4-, which uses only a synthetic polymer binder without using a natural binder, and in which the whitening effect of a fluorescent brightener can be sufficiently exhibited.

(Structure and operation of the invention) The inventors have developed a coating color composition that allows the whitening effect of the fluorescent brightener to be fully exhibited even when only a synthetic polymer binder is used as a binder without using a natural binder. As a result of pursuing this, we discovered 4,4'-bis(2-(2,5-disulfophenylamino)-4-7) as a fluorescent brightener.
It is very satisfactory to use enoxy 1,3,5-triazin-6-ylaminocostilbene-2,2'-disulfonic acid (1) or its water-soluble salts and to add polyethylene glycol in the coating color. The present invention was developed based on the discovery that coated paper with white discoloration can be obtained. That is, the present invention is directed to the production of coated paints containing substantially no natural binders, synthetic polymeric binders, fillers, 4.4'
-bis(2-(2,5-disulfophenylamino)-4
-7 Enoxy sheet Coated, characterized in that a coating color containing 3,5-triazin-6-ylaminocostilbene-2,2'-disulfonic acid or a water-soluble salt thereof and polyethylene glycol is applied to the surface of the paper. This is a paper manufacturing method.

4,4'-bis (2-(2,5) used in the present invention
-disulfophenylamino)-4-phenoxy-1,3
・5-triazin-6-ylaminocostilbene-2・
2'-Disulfonic acid is a fluorescent whitening agent mainly used for cellulose fibers, which is disclosed in JP-A-48-18314 and JP-A-49-31983. It is introduced as a substance that does not easily cause concentration quenching even at high concentrations.

In JP-A No. 49-31983, coated paper with excellent white discoloration is produced using this compound as a fluorescent whitening dye and a coating color containing a mixture of casein and a synthetic binder in equal amounts as a binder. The examples produced are described. However, even if this fluorescent whitening agent is used, if only a synthetic binder is used as the binder, its fluorescent whitening effect is significantly reduced and no practical whitening effect is exhibited.

The inventors have discovered that by adding polyethylene glycol to the coating color, various bistriazinylaminostilbene-based fluorescent brighteners can exert their effects even in coated papers using only synthetic binders. Among them, the present invention was carried out by paying attention to the fact that the stilbene derivative of formula (1) used in the present invention exhibits remarkable effects.

Stilbene derivative (■) (hexasodium salt) in the present invention 1. 4,4'-bis(:2-(2,5-disulfophenylamino)-4-jethanolamino-1,3,5-triazin-6-ylaminocostilbene-2, which has a similar structure to that) Hexasodium 2'-disulfonate (IT) and 4,4'-bis(2
-(4-sulfophenylamino)-4--,7ethanolamino-1,3,5-triazin-6-ylaminocostilbene-2,2'-disulfonic acid tetrasodium pe(1) and 4-(2 -(4-sulfophenylamino)-4-
Jetanolamino-1,3,5-triazin-6-ylamino)-4'-(2-(3-sulfophenylamino)-4-jetanolamino-1,3,5-triazin-6-ylaminoco When a coating color is made using four kinds of fluorescent whitening dyes, such as tetrasodium stilbene-2,2'-disulfonate, and only a synthetic binder as an inder, and polyethylene glycol is not used in combination with them. Table 1 shows a comparison of the effects of these coated paints produced by coating gold on fluorescent brighteners observed under full natural light when used in combination with ◎ Table 1 Fluorescence How the brightening effect appears When not using fluorescent whitening agent PE) C-i pEG'i
When used ■ Slight Significantly obvious ■ Slightly obvious ■ Slightly obvious This table shows the results of comparative observation of the coated paper gums produced in Example 1 and Comparative Examples 1 to 3 under natural light. When polyethylene glycol is not used, there are some differences between the fluorescent whitening effects of the four types of fluorescent brighteners, but all of them show only white discoloration that is not worth practical use. When used, any fluorescent whitening agent clearly exhibits its whitening effect, and among them, the stilbene derivative used in the present invention has a particularly remarkable effect.

The polyethylene glycol used in the present invention has an average molecular weight of about 1000 to 100.

Appropriate. And the amount used is expressed by formula (I)
The effect is observed even at about 0.5 parts per 1 part of the stilbene derivative represented by the formula, but the effect is obvious when the same amount is used, and the effect is even more pronounced when used in double the amount. If you use it more than that, you will see a significant effect.

The amount of the stilbene derivative of formula (I) used in the present invention is not particularly different from the case where a natural binder is also used as a binder, and is approximately 0.025 to 2.5% of the filler used in the coating color. There is no particular need for it to be within this range.

Examples of the synthetic polymer binder used in the present invention include, but are not limited to, styrene-butadiene latex, acrylic ester copolymer latex, vinyl acetate latex, and anionic acrylic copolymer aqueous dispersion. It's not a thing. The amount of these synthetic polymer binders used is not particularly different from the amount used when only a natural binder is used as a binder or the total amount used when a natural binder and a synthetic polymer binder are used together. 10-30% (as solids content) of Note that the anionic acrylic copolymer aqueous suspension can be used in combination with other latexes.

The fillers used in the present invention are those commonly used in coated paper/4, such as clay, talc, kaolin, titanium white, and calcium carbonate.

In the present invention, the coating color applied to the paper surface can of course contain, in addition to the various substances mentioned above, a dispersing agent such as sodium birophosphate, a pull-in agent to adjust the color tone of the paper, and the like.

In the present invention, the method of adding polyethylene glycol to the coating color is not particularly limited. For example, it may be added to a mixed solution of a stilbene derivative and polyethylene glycol, a mixed suspension of a total filler and a binder, or a stilbene derivative may be added to a mixed suspension of a binder. , polyethylene glycol may be added to the mixed suspension of filler and binder.

(Example) Next, an example will be described, but the present invention is not limited thereto.

Example 1 13 parts of the stilbene derivative (hexana) of formula (1) (the same applies hereinafter) and 26 parts of PEG 1540 (polyethylene glycol with an average molecular weight of approximately 1300 to 1600) were dissolved in 61 parts of water (solution A). ). In addition, there is clay (clay made by Katsumitsuyama Mining Co., Ltd.) on Mt. Katsumitsu.
00 parts, Dow Latex 1924 (manufactured by Dow Chemical Co., Ltd., styrene-butadiene rubber latex, solid content 50%) 34 parts, pyrophosphoric acid) 0.5 parts of IJum and 102 parts of water were mixed to make a suspension. I made it (liquid B).

Take 2 parts of Part A and mix well with the entire amount of Part B to make a coating color, and apply this coating color to a non-fluorescent high-quality coat using a wire rod boiler.
A coated paper was prepared by drying with hot air at ℃ for 1 minute. This coach, Dopenoya-, showed a beautiful white color under natural light.

Comparative Example 1 PEG 1540 fi in Solution A of Example 1 was not used, but a 13% aqueous solution of the stilbene derivative of formula (1) was prepared, and this was used in place of Solution IA in the same manner as in Example 1. Created coated paper. This coach.

Even when the paper was observed under natural light, the beautiful whiteness caused by the fluorescent brightener was not observed.

In the same manner as in Comparative Example 1, using the stilbene derivatives of formula (H), formula (g) and formula (IV) in place of the stilbene derivative of formula (I) used in comparative example 1, Coch, Depay/Mother was prepared. -f Created. When these coated papers were observed under natural light, almost no whiteness due to the fluorescent brightener was observed in those using all of the stilbene derivatives of formulas (to) and 2〇V). No such whiteness was observed in the product using the stilbene derivative (n).

Comparative Example 3 A coated paper was prepared in the same manner as in Example 1 using stilbene derivatives of formula (II), formula (to), and formula (IV) in place of the stilbene derivative of formula (I) in Example 1. did. These coaches and papers showed a beautiful whiteness under natural light, but the whiteness was very high.
Example 2 PEG 60 was substituted for PEG 1540 in Example 1.
00 (polyethylene glycol with an average molecular weight of 8,000 to 9,000) in the same manner as in Example 1.
<-i? − was created. This coated paper exhibited beautiful whiteness under natural light, similar to the coated paper of Example 1.

Example 3 Stilbene rust conductor 261% aqueous solution of formula (1) and PE
Add 2 parts each of G 6000 to the B solution (total amount) of Example 1, mix well, and apply a coating color. Created. This paper exhibited an extremely beautiful whiteness under natural light.

Example 4 Ball Latex LX-851 (Nippon Zeon Co., Ltd., acrylic ester copolymer latex, solid content 45%) 37.8.9 was used in place of 34 parts of Dow Latex 1924 in Example 1. In addition, coated paper/'- was prepared in the same manner as in Example 1 using Cevian A (manufactured by Daicel Chemical Industries, Ltd., vinyl acetate latex, solid content 56.3%) 30.0.9. . All of these coated papers exhibited beautiful whiteness similar to the coated paper of Example 1 under natural light.

Example 5 100 parts of Katsukoyama clay, 21 parts of Liquid LC-3-2A (manufactured by Kindai Kagaku Kogyo Co., Ltd., aqueous dispersion of ammonium salt of styrene-maleic acid halfester acrylic copolymer, solid content concentration 10%) , Dow Latex 192410
part, and 0.5 part of sodium birophosphate to 84.5 parts of water.
A suspension (B/liquid) is prepared by thoroughly mixing the solution dissolved in 1 part, and 2.0 parts of a 26% aqueous solution of the stilbene derivative of formula (1) and 2.0 parts of PF:G6000 are added to this and stirred well. A coating color was applied to the paper in the same manner as in Example 1, and dried to prepare a coated paper (coated paper A).

In addition, in place of Liquid LC-3-2A in the above B' solution, Acrosol A 30D (manufactured by BASF, aqueous dispersion of anionic acrylic copolymer, solid content concentration 40%)8.
Using 0 parts, one piece of coated paper was prepared in the same manner as above. (Coated Paper B) When coated papers A and B were observed under natural light, they both exhibited extremely beautiful whiteness.

In addition, instead of Liquid LC-3-2A in the above B' solution, 12.5 parts of milk casein, t2.8% ammonia water 62
．． A suspension 9 is prepared using a thickening agent prepared by combining 5 parts, and in this suspension 26 of the stilbene derivative of formula (I) is added.
Add 2.0 parts of gold to the water bath solution to make a coating color, and use this to coat coated paper in the same manner as above.
It was created. When observed under natural light, the whiteness of this coated paper was not as good as that of coated paper/'P-A and B.

Furthermore, in the coach, Dopeno 9-, which was prepared by adding only 2.0 parts of a 26% aqueous solution of the stilbene derivative of formula (I) to solution B, almost no fluorescent whitening effect was observed due to the stilbene derivative.

Claims (1)

[Claims] In the production of coated paper that does not substantially use natural binders, synthetic polymer binders, fillers, 4.4
'-Bis[:2-(,2,5-disulfophenylamino)-4-phenoxy-1,3,5-triazin-6-ylaminocostilbene-2,2'-disulfonic acid or its water-soluble salt A method for producing coated paper, which comprises applying a coating color containing polyethylene glycol to the surface of the paper.