阅读说明：本技术 一种白面牛卡纸及其制备方法 (White craft paper and preparation method thereof ) 是由 郭彩云 周军锋 刘宽伟 于 2020-06-17 设计创作，主要内容包括：本发明公开一种白面牛卡纸及其制备方法,涉及牛卡纸制造技术领域,以克服现有技术中白面牛卡纸易分层、断裂和爆皮的缺陷,并提升白面牛卡纸的环保性能。白面牛卡纸,包括面纸层、底纸层、面涂层以及位面纸层和底纸层之间的芯纸层,面纸层、芯纸层和底纸层采用三叠网成形技术制作而成。面涂层是以面涂料采用气帘一次涂布的方式形成在所述面纸层远离芯纸层的表面,底纸层采用底纸层浆料抄造而成,芯纸层采用芯纸层浆料抄造而成,面纸层采用面纸层浆料抄造而成；所述底纸层浆料包括OCC浆,芯纸层浆料包括ONP浆和OMG浆,所述面纸层浆料包括MOW浆和竹浆。所述制备方法用于制备上述白面牛卡纸。本发明提供的白面牛卡纸用于白板纸中。(The invention discloses a white craft paper and a preparation method thereof, relates to the technical field of craft paper manufacturing, and aims to overcome the defects that the white craft paper is easy to delaminate, break and crack in the prior art and improve the environmental protection performance of the white craft paper. The white craft paper comprises a surface paper layer, a bottom paper layer, a surface coating layer and a core paper layer arranged between the surface paper layer and the bottom paper layer, wherein the surface paper layer, the core paper layer and the bottom paper layer are manufactured by adopting a three-folded net forming technology. The surface coating is formed on the surface of the surface paper layer far away from the core paper layer by adopting a mode of air curtain one-time coating of the surface coating, the base paper layer is made by adopting base paper layer slurry, the core paper layer is made by adopting core paper layer slurry, and the surface paper layer is made by adopting surface paper layer slurry; the base paper layer slurry comprises OCC slurry, the core paper layer slurry comprises ONP slurry and OMG slurry, and the surface paper layer slurry comprises MOW slurry and bamboo slurry. The preparation method is used for preparing the white top kraft liner board. The white craft paper provided by the invention is used in white board paper.)

1. The white craft paper is characterized by comprising a surface paper layer, a bottom paper layer, a top coating layer and a core paper layer positioned between the surface paper layer and the bottom paper layer, wherein the surface paper layer, the core paper layer and the bottom paper layer are manufactured by adopting a three-folded-net forming technology, the top coating layer is formed on the surface of the surface paper layer far away from the core paper layer in a mode that a surface coating adopts an air curtain to coat for one time, the bottom paper layer is manufactured by adopting bottom paper layer slurry, the core paper layer is manufactured by adopting core paper layer slurry, and the surface paper layer is manufactured by adopting surface paper layer slurry; the base paper layer slurry comprises OCC slurry, the core paper layer slurry comprises ONP slurry and OMG slurry, and the surface paper layer slurry comprises MOW slurry and bamboo slurry.

2. The kraft liner board according to claim 1, wherein the grammage of the liner layer is in the range of 35g/m²~50g/m²The grammage of the core paper layer is in the range of 55g/m²~80 g/m²The gram weight of the base paper layer is in the range of 55g/m²~80g/m²(ii) a The coating weight of the top coating is 7g/m²～10g/m²。

3. The white craft paper according to claim 1, characterized in that the mass ratio of the base paper layer slurry used for the base paper layer, the core paper layer slurry used for the core paper layer and the face paper layer slurry used for the face paper layer is (33-56): (22-45): (22-45).

4. The white top kraft liner board according to claim 1, wherein the base paper layer slurry further comprises a dry strength agent, β -glucosidase and polyethyleneimine, the base paper layer slurry contains 98% to 98.9% by mass of OCC slurry, the base paper layer slurry contains 0.5% to 1.4% by mass of the dry strength agent, the base paper layer slurry contains 0.55% to 0.9% by mass of the β -glucosidase, and the base paper layer slurry contains 0.05% to 0.1% by mass of the polyethyleneimine.

5. The white craft paper according to claim 1, characterized in that the core paper layer slurry further comprises lactic acid modified chitosan, a dry strength agent and polyethyleneimine, the core paper layer slurry contains ONP slurry and OMG slurry with a total mass percentage of 96.5-97.8%, the core paper layer slurry contains lactic acid modified chitosan with a mass percentage of 1.2-2.5%, the core paper layer slurry contains the dry strength agent with a mass percentage of 0.95-2.0%, the core paper layer slurry contains polyethyleneimine with a mass percentage of 0.05-0.1%, and the absolute dry mass ratio of the ONP slurry to the absolute dry mass ratio of the OMG slurry is (15-25): (75-85).

6. The white top kraft liner board according to claim 1, wherein the top paper layer further comprises precipitated calcium carbonate, titanium dioxide, lactic acid modified chitosan, a dry strength agent and polyethyleneimine, the top paper layer comprises 65-75% of MOW pulp and bamboo pulp by mass, the top paper layer comprises 16-28% of precipitated calcium carbonate by mass, the top paper layer comprises 4-8% of titanium dioxide by mass, the top paper layer comprises 2.0-3.0% of lactic acid modified chitosan by mass, the top paper layer comprises 0.95-2.0% of dry strength agent by mass, and the top paper layer comprises 0.05-0.1% of polyethyleneimine by mass; the mass ratio of the oven dry mass of the MOW pulp to the oven dry mass of the bamboo pulp is (85-95): (5-15).

7. The kraft liner board according to any one of claims 4 to 6, wherein the dry strength agent is polyacrylamide with a molecular weight in the range of 25 to 35 ten thousand, and the polyethyleneimine with a molecular weight in the range of 30 to 50 ten thousand.

8. The white craft paper according to claim 1, characterized in that the top coating comprises, by mass, 2-5 parts of nano cellulose, 10-18 parts of styrene-butadiene latex, 1-2 parts of ethylene-vinyl acetate copolymer, 60-70 parts of kaolin, 0.60-0.9 part of CMC, 0.5-3 parts of basalt fiber, 0.5-1 part of defoamer, 0.3-0.6 part of brightener, and 0.4-1.1 part of preservative.

9. A method for preparing the kraft white cardboard according to any one of claims 1 to 8, comprising:

using the base paper layer slurry, the core paper layer slurry and the surface paper layer slurry to manufacture a composite paper layer consisting of the base paper layer, the core paper layer and the surface paper layer, wherein the core paper layer is positioned between the surface paper layer and the base paper layer;

carrying out post-treatment on the composite paper layer to obtain composite base paper;

and coating a surface coating on the surface of the surface paper layer contained in the composite base paper by adopting an air curtain coating process to obtain the white craft paper.

10. The method for preparing a kraft liner board according to claim 9, wherein the step of using the ground paper layer slurry, the core paper layer slurry and the face paper layer slurry to manufacture the composite paper layer consisting of the ground paper layer, the core paper layer and the face paper layer comprises:

manufacturing a bottom paper layer, a core paper layer and a surface paper layer by using three-folded net forming equipment to obtain a wet paper web; the speed of the three-lap net forming equipment is 700-1000 m/min.

Squeezing and dehydrating the wet paper web by adopting a squeezing line to obtain a composite paper layer; the first pressing pressure of the pressing line is 800kN/m, and the second pressing pressure is 1000 kN/m;

the post-treatment of the composite paper layer to obtain the composite base paper comprises the following steps:

performing surface calendering on the composite paper layer by using calendering light to obtain composite base paper; the line pressure range of the calendering line is 65-85 kN/m, and the calendering temperature of the calendering line is 100-130 ℃.

Technical Field

The invention belongs to the technical field of craft paper manufacturing, and particularly relates to a white craft paper and a preparation method thereof.

Background

With the development of modernization of paper packaging industry, the demand of medium-high grade box board is obviously increased, the market demand of raw material kraft paper is greatly increased, and higher requirements are provided for the product quality.

The traditional white craft paper is generally a single-layer structure formed by single-net papermaking. In order to increase the thickness and stiffness thereof to provide better packing properties, white top craft paper is gradually developed into a two-layer or multi-layer structure formed by a double-layer or multi-net papermaking and recombination method. The strength and the stiffness of the white craft paper are improved due to the increase of the thickness of the white craft paper, but the problem that the white craft paper is broken due to the interlayer separation of the white craft paper frequently occurs in the use process due to the lower interlayer bonding strength of the white craft paper in the compounding process. Wherein, for cardboard paper and white board paper, the requirement of paper front bursting of the white craft paper is higher; for liquid packaging paper, the requirement of back surface line bursting/bursting of the white craft paper is higher. Therefore, the folding endurance adjustment is often of a great importance for white top craft paper with different requirements.

Disclosure of Invention

The invention aims to provide a white craft paper and a preparation method thereof, so as to overcome the defects of easy delamination, breakage and skin explosion of the white craft paper in the prior art and improve the environmental protection performance of the white craft paper.

In order to achieve the purpose, the invention provides a white craft paper, which comprises a surface paper layer, a bottom paper layer, a top coating layer and a core paper layer positioned between the surface paper layer and the bottom paper layer, wherein the surface paper layer, the core paper layer and the bottom paper layer are manufactured by adopting a three-folded-net forming technology, the top coating layer is formed on the surface of the surface paper layer far away from the core paper layer in a mode of one-time coating of a top coating by adopting an air curtain, the bottom paper layer is manufactured by adopting bottom paper layer slurry, the core paper layer is manufactured by adopting core paper layer slurry, and the surface paper layer is manufactured by adopting surface paper layer slurry; the base paper layer slurry comprises OCC slurry, the core paper layer slurry comprises ONP slurry and OMG slurry, and the surface paper layer slurry comprises MOW slurry and bamboo slurry.

Compared with the prior art, in the white top craft paper provided by the invention, the surface paper layer, the bottom paper layer and the core paper layer are made of degradable materials through a three-fold net forming technology, so that the white top craft paper has good environmental protection performance, and meanwhile, the surface paper layer, the bottom paper layer and the core paper layer are mutually matched, so that the surface paper layer, the bottom paper layer and the core paper layer have good tightness and integrity and are not easy to delaminate. In addition, the surface coating is formed on the surface of the surface paper layer far away from the core paper layer in an air curtain type one-time coating mode, so that the coating forming the surface coating can be well distributed in the transverse direction and the longitudinal direction of the paper web, and crease formation is avoided. And a smooth surface coating can be obtained through one-time coating operation, so that the white craft paper has good folding strength and printing performance, the production speed is high, and the production cost of the white craft paper is reduced.

Therefore, the white top craft paper provided by the invention not only has good anti-delamination and anti-explosion performance, but also has good environmental protection performance.

The invention also provides a preparation method of the white top kraft liner board, which comprises the following steps:

using the base paper layer slurry, the core paper layer slurry and the surface paper layer slurry to manufacture a composite paper layer consisting of the base paper layer, the core paper layer and the surface paper layer, wherein the core paper layer is positioned between the surface paper layer and the base paper layer;

carrying out post-treatment on the composite paper layer to obtain treated base paper;

and coating a surface coating on the surface of the surface paper layer contained in the treated base paper by adopting an air curtain coating process to obtain the white craft paper.

Compared with the prior art, the preparation method of the white-top kraft liner board provided by the invention has the same beneficial effects as the white-top kraft liner board in the technical scheme, and the details are not repeated herein.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a white craft paper provided in an embodiment of the present invention;

fig. 2 is a flow chart of preparation of the white craft paper provided by the embodiment of the invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.