阅读说明：本技术 一种高性能低定量字典纸及其制备方法 (High-performance low-quantitative dictionary paper and preparation method thereof ) 是由 王敏良 戴贤中 赵建华 毛学米 杨昌余 江利 于 2020-04-13 设计创作，主要内容包括：本发明公开了一种高性能低定量字典纸及其制备方法,包括植物纤维层和设置在植物纤维层两侧的涂层,纸张定量22~30g/m<Sup>2</Sup>,制备植物纤维层的浆料包括质量分数为45~65%的漂白本色针叶木浆及35%~55%的漂白阔叶木浆,制备涂层的涂料以重量份记,原料包括：200~300份改性填料,40~60份助留剂,1~2份保水剂,1~3份润滑剂,0.05~0.1份消泡剂,5~10份氢氧化钠以及500~1000份水。本发明在植物纤维层两侧的涂层中使用改性填料,改性填料表面引入的物质可以与纤维发生反应从而使将填料与纤维层牢固连接,提高填料的留着率；并且可以通过吸附油墨中的呈色物质防止透页和脱墨现象发生。(The invention discloses high-performance low-quantitative dictionary paper and a preparation method thereof, wherein the high-performance low-quantitative dictionary paper comprises a plant fiber layer and coatings arranged on two sides of the plant fiber layer, and the paper ration is 22-30 g/m 2 The slurry for preparing the plant fiber layer comprises 45-65% of bleached natural-color softwood pulp and 35-55% of bleached hardwood pulp in mass fraction, the coating for preparing the coating is recorded in parts by weight, and the raw materials comprise: 200-300 parts of modified filler, 40-60 parts of retention aid, 1-2 parts of water-retaining agent, 1-3 parts of lubricant, 0.05-0.1 part of defoaming agent, 5-10 parts of sodium hydroxide and 500-1000 parts of water. According to the invention, the modified filler is used in the coatings on the two sides of the plant fiber layer, and substances introduced into the surface of the modified filler can react with the fiber, so that the filler is firmly connected with the fiber layer, and the retention rate of the filler is improved; and can prevent page through and deinking phenomena by adsorbing color-producing substances in the ink.)

1. The high-performance low-quantitative dictionary paper is characterized by comprising a plant fiber layer and coatings arranged on two sides of the plant fiber layer, and the paper is quantitative by 22-30 g/m²The slurry for preparing the plant fiber layer comprises 45-65% of bleached natural color softwood pulp and 35-55% of bleached hardwood pulp in mass fraction, and the coating for preparing the coating comprises the following raw materials in parts by weight: 200-300 parts of modified filler, 40-60 parts of retention aid, 1-2 parts of water-retaining agent, 1-3 parts of lubricant, 0.05-0.1 part of defoaming agent, 5-10 parts of sodium hydroxide and 500-1000 parts of water.

2. The high-performance low-basis weight dictionary paper as claimed in claim 1, wherein the modified filler in the coating comprises one or two of modified light calcium carbonate and modified titanium dioxide, and the preparation method comprises:

A) dispersing light calcium carbonate or titanium dioxide in xylene, adding gamma-chloropropyltrimethoxysilane, heating at 75-85 ℃ for reaction for 8-10 h, filtering, and extracting the product in toluene for 20-30 h to obtain chloropropylated filler; the mass-volume ratio of the light calcium carbonate or titanium dioxide to the gamma-chloropropyl trimethoxyl silane is 1 g: (1-2 mL);

B) adding chloropropylated filler into a mixed solution of a polyepichlorohydrin-dimethylamine solution and NaOH, stirring and reacting for 3-5 h at the temperature of 85-95 ℃, wherein the mass fraction of the polyepichlorohydrin-dimethylamine in the mixed solution is 10-15%, the mass fraction of the sodium hydroxide is 4-6%, and the mass-volume ratio of the added chloropropylated filler to the mixed solution is 1 g: (20-30 mL);

C) adding polyethyleneimine into the solution reacted in the step B), wherein the mass ratio of the polyethyleneimine to the polyepichlorohydrin-dimethylamine is 1 (1-3), continuously stirring and reacting for 3-5 h at 85-95 ℃, filtering, washing the product with methanol and water, and drying to obtain the modified filler.

3. The high performance low basis weight dictionary paper as claimed in claim 1, wherein said retention aid in the coating is one or more of cationic starch, styrene-butadiene latex and polyvinyl alcohol.

4. A high performance low basis weight dictionary paper as claimed in claim 1 wherein said water retaining agent in the coating is sodium carboxymethyl cellulose or chitosan.

5. A high performance low basis weight dictionary paper as claimed in claim 1 wherein said lubricant in the coating is calcium stearate.

6. The high performance low basis weight dictionary paper as claimed in claim 1, wherein said defoamer in the coating is a polyether defoamer or a silicone defoamer.

7. The high-performance low-basis weight dictionary paper according to claim 1, wherein the pulp size of the plant fiber layer is 65 to 73oSR, the wet weight is 2.0 to 3.0g, the pH is 7.5 to 8.5, and 0.5 to 1.0kg of deaerator, 5 to 8kg of size inner glue and 3 to 10kg of AKD are added to the pulp.

8. A high performance low basis weight dictionary paper according to claim 7 wherein said size is cationic starch and said AKD is alkyl ketene dimer.

9. A method for preparing high-performance low-basis weight dictionary paper according to any one of claims 1 to 8, comprising the steps of:

(1) preparing pulp of the plant fiber layer after grinding, and adding AKD, pulp internal glue and a degassing agent into the pulp;

(2) making paper sheets by screening the pulp;

(3) pressing and pre-drying the paper sheet;

(4) coating the paper on both sides by using the coating, wherein the coating weight of both sides is 3-5 g/m²；

(5) The coated paper sheet enters a non-contact hot air drying box for pre-drying, and then enters a post-drying part for final drying;

(6) and performing calendaring on the dried paper sheet to obtain the high-performance low-basis-weight dictionary paper.

10. The high-performance low-basis weight dictionary paper according to claim 9, wherein the concentration of the on-line paper during the paper making in the step (2) is 0.5 to 0.6%, and the speed of the vehicle is 500 to 600 m/min; the moisture content of the paper sheet after the front drying in the step (3) is 10-15%; and (5) the moisture content of the finally dried paper sheet in the step (5) is 3-5%.

Technical Field

The invention relates to the technical field of papermaking, in particular to high-performance low-quantitative dictionary paper and a preparation method thereof.

Background

The dictionary paper is a high-grade printing paper, and is characterized by high opacity, smoothness and durability, and the paper surface needs to be white, fine, tough and folding-resistant. The opacity, whiteness and ink absorption of the dictionary paper are generally improved by adding calcium carbonate and other fillers in the preparation process of the dictionary paper, for example, in the Chinese patent document, "a production method of coating dictionary paper", publication No. CN102839559B, the dictionary paper is prepared by a double-sided coating method, and the formula of the coating comprises: 80 parts of heavy ultrafine calcium carbonate, 20 parts of rutile titanium dioxide, 10-15 parts of styrene-butadiene latex, 15-20 parts of quaternary amine cationic starch, 0.3-0.5 part of water-retaining agent, 0.01-0.03 part of dispersing agent, 0.5-0.7 part of lubricating agent and 0.01-0.03 part of defoaming agent. This patent improves the smoothness of the paper sheet by coating both sides of the plant fiber layer with coatings having fillers, and increases the opacity of the paper sheet because the coatings on both sides have different refractive indices from the middle layer.

However, in the existing papermaking technology, retention aids such as cationic starch and the like are mainly combined with fibers to form a net through which flocs cannot pass, so that the filler and fine fibers are retained in paper sheets to improve the retention rate of the filler. And the filler has small particle size and is easy to agglomerate, so that the light scattering performance and the paper uniformity are influenced.

Disclosure of Invention

The invention aims to overcome the defects that in the existing dictionary paper preparation process, as the binding force between the filler and the fiber is not available, the filler is easy to separate from flocculate under the action of external force and run off, the retention rate of the filler is not high, and the paper performance is influenced; the filler has small particle size and is easy to agglomerate, the light scattering performance of the filler and the uniformity of paper are influenced, and the high-performance low-quantitative dictionary paper and the preparation method thereof are provided.

In order to achieve the purpose, the invention adopts the following technical scheme:

a high-performance low-quantitative dictionary paper comprises a plant fiber layer and coatings arranged on two sides of the plant fiber layer, wherein the paper is quantitative by 22-30 g/m²The slurry for preparing the plant fiber layer comprises 45-65% of bleached natural-color softwood pulp and 35-55% of bleached hardwood pulp in mass fraction, the coating for preparing the coating is recorded in parts by weight, and the raw materials comprise: 200-300 parts of modified filler, 40-60 parts of retention aid, 1-2 parts of water-retaining agent, 1-3 parts of lubricant, 0.05-0.1 part of defoaming agent, 5-10 parts of sodium hydroxide and 500-1000 parts of water.

Preferably, the modified filler in the coating comprises one or two of modified light calcium carbonate and modified titanium dioxide, and the preparation method comprises the following steps:

A) dispersing light calcium carbonate or titanium dioxide in xylene, adding gamma-chloropropyltrimethoxysilane, heating at 75-85 ℃ for reaction for 8-10 h, filtering, and extracting the product in toluene for 20-30 h to obtain chloropropylated filler; the mass-volume ratio of the light calcium carbonate or titanium dioxide to the gamma-chloropropyl trimethoxyl silane is 1 g: (1-2 mL);

B) adding chloropropylated filler into a mixed solution of a polyepichlorohydrin-dimethylamine solution and NaOH, stirring and reacting for 3-5 h at the temperature of 85-95 ℃, wherein the mass fraction of the polyepichlorohydrin-dimethylamine in the mixed solution is 10-15%, the mass fraction of the sodium hydroxide is 4-6%, and the mass-volume ratio of the added chloropropylated filler to the mixed solution is 1 g: (20-30 mL);

C) adding polyethyleneimine into the solution reacted in the step B), wherein the mass ratio of the polyethyleneimine to the polyepichlorohydrin-dimethylamine is 1 (1-3), continuously stirring and reacting for 3-5 h at 85-95 ℃, filtering, washing the product with methanol and water, and drying to obtain the modified filler.

Detailed Description

The invention is further described with reference to specific embodiments. The raw materials used in the examples of the present invention are commercially available or commonly used in the art, unless otherwise specified.