阅读说明：本技术 一种适用于抗回潮牛皮挂面箱板纸的施胶工艺 (Sizing process suitable for moisture regain resistant kraft liner box board paper ) 是由 李文斌 于 2020-12-22 设计创作，主要内容包括：本发明公开了一种适用于抗回潮牛皮挂面箱板纸的施胶工艺。包括以下步骤：(1)玉米淀粉预处理；(2)施胶剂准备；(3)施胶：对纸幅干燥后进行施胶；(4)施胶后处理。本发明的施胶工艺采用聚乙烯醇、二氧化钛与玉米淀粉进行混合制备新型施胶剂,使施胶剂具有良好的疏水功能,同时,又加入了壳聚糖提高了施胶剂的胶黏性。(The invention discloses a sizing process suitable for moisture regain resistant kraft liner box board paper. The method comprises the following steps: (1) pretreating corn starch; (2) preparing a sizing agent; (3) sizing: drying the paper web and then sizing; (4) and (5) sizing and post-treatment. The sizing process of the invention adopts polyvinyl alcohol, titanium dioxide and corn starch to mix to prepare the novel sizing agent, so that the sizing agent has good hydrophobic function, and simultaneously, chitosan is added to improve the viscosity of the sizing agent.)

1. A sizing process suitable for moisture regain resistant kraft liner box board paper is characterized by comprising the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; obtaining a starch solution for later use;

(2) preparation of sizing agent: mixing polyvinyl alcohol and water, placing the mixture into a reaction kettle, adding the starch solution obtained in the step (1) into the reaction kettle, adding titanium dioxide and chitosan, fully mixing, adding aluminum sulfate, and placing the mixture into a sizing machine;

(3) sizing: drying the paper web and then sizing;

(4) sizing post-treatment: drying is carried out again after sizing is finished.

2. The sizing process of claim 1, wherein in the step (1), the weight part of the water is 70-100 parts and the weight part of the amylase is 0.0005-0.0008 part based on 10 parts of the weight part of the corn starch.

3. The sizing process suitable for the moisture regain resistant kraft liner box board paper as claimed in claim 1 or 2, wherein the starch solution is 50-60 parts by weight, and the rest of the raw materials are 50-60 parts by weight of polyvinyl alcohol, 50-60 parts by weight of water, 10-12 parts by weight of titanium dioxide, 20-30 parts by weight of chitosan and 3-8 parts by weight of aluminum sulfate.

4. The process of claim 1, wherein in step (2), the sizing agent is first placed in the feed tank, passed through the pressure screen, and then placed in the size press.

5. The process of claim 4, wherein an external sizing agent is filtered and placed in the feed tank, and the weight ratio of the external sizing agent to the sizing agent is 1: 5-6.

6. The process of claim 1, wherein the starch solution in step (1) is maintained at a temperature of 85-90 ℃ for use.

7. A process for sizing a moisture regain resistant kraft liner board paper as claimed in claim 1, wherein the web is dried at 60-80 ℃ and then double-side sized.

8. The process of claim 1, wherein the kraft liner board paper is dried at a temperature of 60-80 ℃ after sizing.

Technical Field

The invention relates to a sizing process suitable for moisture regain resistant kraft liner boxboard paper, and belongs to the technical field of papermaking.

Background

The cardboard paper is mainly applied to the packaging industry, most enterprises adopt waste cartons for production due to shortage of paper pulp raw materials, and the paper produced by the waste paper raw materials has low strength and poor quality. In order to meet the requirements of users for paper strength and other properties, general paper-making enterprises apply surface sizing to improve various performance indexes of paper and paperboard, including paper strength such as bursting strength, ring crush strength, tensile strength, folding strength and the like.

Surface sizing is a method of sizing both sides of paper or board with an aqueous dispersion containing one or more surface sizing agents in a specific apparatus. Most surface sizing agents are composed of a hydrophobic group resistant to water and a hydrophilic group having affinity for the pulp. The hydrophobic group is styrene, olefin, vinyl, etc.; examples of the hydrophilic group include maleic acid and acrylic acid containing a carboxyl group (anionic group), and dimethylamino acrylic acid vinegar containing an amino group (cationic group). When they are coated on the surface of paper, a part of surface sizing liquid can be permeated into the paper layer to fill the gaps in the paper layer; another part will remain on the surface of the sheet. During the drying process, the polymer behaves thermoplastically, since its glass transition temperature is lower than ambient temperature. In this way, the polymer particles will spread out on the surface of the fibers. At this time, the anionic group (-COOR) in the surface sizing agent is adsorbed by the cationically activated portion of the aluminum sulfate or cationic polymer in the paper layer to form a continuous film, thereby exhibiting sizing properties. In addition, surface sizing can improve the surface strength, the internal bonding degree, the IGT napping speed, the air permeability, the stiffness and the smoothness of paper, improve the printing performance, and improve the grease resistance and the oil resistance of the paper.

However, the current sizing agents do not provide good moisture regain resistance to the paper web after use and require further strengthening.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a sizing process suitable for moisture regain resistant kraft liner boxboard paper.

The invention is realized by the following technical scheme:

a sizing process suitable for moisture regain resistant kraft liner box board paper comprises the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; obtaining a starch solution for later use;

(2) preparation of sizing agent: mixing polyvinyl alcohol and water, placing the mixture into a reaction kettle, adding the starch solution obtained in the step (1) into the reaction kettle, adding titanium dioxide and chitosan, fully mixing, adding aluminum sulfate, and placing the mixture into a sizing machine;

(3) sizing: drying the paper web and then sizing;

(4) sizing post-treatment: drying is carried out again after sizing is finished.

The sizing process suitable for the moisture regain resistant kraft liner linerboard paper comprises the following steps of (1), by weight, 10 parts of corn starch, 70-100 parts of water and 0.0005-0.0008 part of amylase.

The sizing process suitable for the moisture regain resistant kraft liner box board paper comprises 50-60 parts by weight of starch solution, 50-60 parts by weight of polyvinyl alcohol, 50-60 parts by weight of water, 10-12 parts by weight of titanium dioxide, 20-30 parts by weight of chitosan and 3-8 parts by weight of aluminum sulfate.

In the step (2), the sizing agent is firstly placed in the feeding tank, passes through the pressure screen and then is placed in the sizing machine.

The sizing process suitable for the moisture regain resistant kraft liner box board paper is characterized in that an outsourcing sizing agent is filtered and then placed in a feeding groove, and the weight ratio of the outsourcing sizing agent to the sizing agent is 1: 5-6.

The sizing process suitable for the moisture regain resistant kraft liner box board paper is characterized in that the temperature of the starch solution in the step (1) is kept between 85 and 90 ℃ during standby.

The sizing process is suitable for the moisture regain resistant kraft liner linerboard, and the paper web is dried at 60-80 ℃ and then subjected to two-side sizing.

The sizing process is suitable for the moisture regain resistant kraft liner linerboard, and drying is carried out at the temperature of 60-80 ℃ after sizing.

The invention achieves the following beneficial effects:

the sizing process of the invention adopts polyvinyl alcohol, titanium dioxide and corn starch to mix to prepare the novel sizing agent, so that the sizing agent has good hydrophobic function, and simultaneously, chitosan is added to improve the viscosity of the sizing agent.

The fine dried noodle cardboard paper prepared by the sizing process has the advantages that the interlayer binding force of finished paper reaches 450KN/m, the water absorption degree of the finished paper reaches 40s/50s on the front side and the back side, and the complete penetration of paper sheets is more than 180 s. The energy consumption of the finished paper reaches 195kgce/t, and reaches an advanced value specified in GB 31825-.

Drawings

FIG. 1 is a process flow diagram of the present invention.

Detailed Description

The invention is further described below. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

External sizing agents were purchased from Jiangsu Fu vast science and technology, Inc.

Example 1

The specific flow is shown in fig. 1, and the sizing process suitable for the moisture regain resistant kraft liner box board paper comprises the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; keeping the temperature at 85-90 ℃ to obtain a starch solution for later use;

(2) preparation of sizing agent: mixing polyvinyl alcohol and water, placing the mixture into a reaction kettle, adding the starch solution obtained in the step (1) into the reaction kettle, adding titanium dioxide and chitosan, fully mixing, adding aluminum sulfate, and placing the mixture into a sizing machine;

(3) sizing: drying the paper web at 60-80 ℃ and then performing two-side sizing;

(4) sizing post-treatment: drying at 60-80 deg.C, calendering, and coiling.

In the step (1), the weight part of the corn starch is 10 parts, the weight part of the water is 70 parts, and the weight part of the amylase is 0.0005 part.

The starch solution is 50 parts by weight, and the rest raw materials are 50 parts by weight of polyvinyl alcohol, 50 parts by weight of water, 10 parts by weight of titanium dioxide, 20 parts by weight of chitosan and 3 parts by weight of aluminum sulfate.

In the step (2), the sizing agent is firstly placed in the feeding tank, passes through the pressure screen and then is placed in the sizing machine. And filtering the purchased sizing agent and then placing the filtered purchased sizing agent in a feeding tank, wherein the weight ratio of the purchased sizing agent to the sizing agent is 1: 5.

Example 2

The specific flow is shown in fig. 1, and the sizing process suitable for the moisture regain resistant kraft liner box board paper comprises the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; keeping the temperature at 85-90 ℃ to obtain a starch solution for later use;

(2) preparation of sizing agent: mixing polyvinyl alcohol and water, placing the mixture into a reaction kettle, adding the starch solution obtained in the step (1) into the reaction kettle, adding titanium dioxide and chitosan, fully mixing, adding aluminum sulfate, and placing the mixture into a sizing machine;

(3) sizing: drying the paper web at 60-80 ℃ and then performing two-side sizing;

(4) sizing post-treatment: drying at 60-80 deg.C, calendering, and coiling.

In the step (1), the weight parts of the corn starch are 10, the weight parts of the water are 100, and the weight parts of the amylase are 0.0008.

The starch solution is 60 parts by weight, and the rest raw materials are 60 parts by weight of polyvinyl alcohol, 60 parts by weight of water, 12 parts by weight of titanium dioxide, 30 parts by weight of chitosan and 8 parts by weight of aluminum sulfate.

In the step (2), the sizing agent is firstly placed in the feeding tank, passes through the pressure screen and then is placed in the sizing machine. And filtering the purchased sizing agent and then placing the filtered purchased sizing agent in a feeding tank, wherein the weight ratio of the purchased sizing agent to the sizing agent is 1: 6.

Example 3

The specific flow is shown in fig. 1, and the sizing process suitable for the moisture regain resistant kraft liner box board paper comprises the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; keeping the temperature at 85-90 ℃ to obtain a starch solution for later use;

(2) preparation of sizing agent: mixing polyvinyl alcohol and water, placing the mixture into a reaction kettle, adding the starch solution obtained in the step (1) into the reaction kettle, adding titanium dioxide and chitosan, fully mixing, adding aluminum sulfate, and placing the mixture into a sizing machine;

(3) sizing: drying the paper web at 60-80 ℃ and then performing two-side sizing;

(4) sizing post-treatment: drying at 60-80 deg.C, calendering, and coiling.

In the step (1), the weight part of the corn starch is 10 parts, the weight part of the water is 80 parts, and the weight part of the amylase is 0.0006 part.

55 parts of polyvinyl alcohol, 55 parts of water, 11 parts of titanium dioxide, 25 parts of chitosan and 6 parts of aluminum sulfate.

In the step (2), the sizing agent is firstly placed in the feeding tank, passes through the pressure screen and then is placed in the sizing machine. And filtering the purchased sizing agent and then placing the filtered purchased sizing agent in a feeding tank, wherein the weight ratio of the purchased sizing agent to the sizing agent is 1: 5.

Comparative example 1

A sizing process suitable for moisture regain resistant kraft liner box board paper comprises the following steps:

(1) corn starch pretreatment: mixing corn starch, water and amylase, reacting for 60-90min, heating to 85-90 ℃, reacting for 20-30min, heating to 130-140 ℃, and reacting for 5-10 min; keeping the temperature at 85-90 ℃ to obtain a starch solution for later use;

(2) preparation of sizing agent: filtering an external sizing agent, placing the filtered external sizing agent in a feeding tank, and then placing the filtered external sizing agent in a sizing machine;

(3) sizing: drying the paper web at 60-80 ℃ and then performing two-side sizing;

(4) sizing post-treatment: drying at 60-80 deg.C, calendering, and coiling.

The papers of the examples and comparative examples were examined for their physical properties according to GB/T460-1989. the results are shown in Table 1, wherein the adhesion is measured by peeling the paper in the 180 ℃ direction at a peeling speed of 1m/min using a tensile tester to measure the peel strength, and the peel strength is used as the adhesion.

TABLE 1 paper-related physical index test results of examples and comparative examples

According to the table 1, the sizing agent is added in the embodiments 1, 2 and 3, the obtained fine dried noodle cardboard paper has a good moisture regain resistant effect, and the sizing agent is prepared with the corn starch by utilizing the hydrophobic characteristics of the polyvinyl alcohol and the titanium dioxide, so that the surface of the paper has a sizing coating with a high-strength waterproof function, and the water resistance of the paper is improved.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.