A method for preparing low-weight textured base paper

Abstract

The present application relates to the technical field of papermaking, and in particular to a method for preparing a low-weight textured base paper, comprising the following steps: uniformly mixing 60-70 parts of bleached bamboo pulp after beating, 28-40 parts of bleached conifer pulp after beating, 0.5-1 parts of a humidifying strength agent, 0.5-0.8 parts of a textured agent and 0.2-0.6 parts of a coating agent according to weight proportions, preparing a slurry, wet paper forming and calendering and winding, and the obtained low-weight textured base paper has good strength, elongation, glossiness and processability, performs well in subsequent coating and processing processes, and can be widely used in gift packaging, publishing and printing, environmentally friendly packaging and other fields.

Description

Technical Field

[0001] The present application relates to the technical field of papermaking, and in particular to a method for preparing low-weight textured base paper. Background Art

[0002] Masking paper is a high-tech decorative and spraying paper, which is widely used in interior decoration, spray painting of household appliances and spray painting of high-end luxury cars. The color separation effect of masking paper is clear and distinct, and it also has the effect of arc art, which has brought a new technological revolution to the decoration and spraying industry and brought new vitality to the industry.

[0003] Masking paper is the surface coating layer and protective layer of masking base paper. The performance of masking base paper directly affects the performance of masking paper, especially the elongation and the bonding strength between masking base paper and surface coating.

[0004] Masking base paper requires good uniformity and high strength. The pulp is generally based on bleached coniferous pulp. When the masking base paper is impregnated, the base paper is required to have a certain wet strength; in order to ensure good absorbency of the base paper, the pulp is generally not sizing, or a very small amount of sizing agent is added to adjust the absorption performance of the base paper. The elongation elongation is generally guaranteed to be above 7%. At present, the weight of masking base paper is above 38 grams / square to meet the above performance requirements, but the strength, coating performance during post-processing, elongation and other performance indicators of low-weight masking base paper cannot meet the actual application requirements. Therefore, the development of a low-weight masking base paper has practical application value and market value. Summary of the invention

[0005] The purpose of this application is to provide a method for preparing low-weight masking base paper in response to the shortcomings of current technology. The obtained low-weight masking base paper has good strength, elongation, glossiness and processability, performs well in subsequent coating and processing, and can be widely used in gift packaging, publishing and printing, environmentally friendly packaging and other fields.

[0006] To achieve the above objectives, this application provides the following technical solutions:

[0007] A method for preparing low-weight masking base paper comprises the following steps:

[0008] S1. Prepare pulp: Mix 60-70 parts of bleached bamboo pulp, 28-40 parts of bleached conifer pulp, 0.5-1 part of a moistening agent, 0.5-0.8 part of a grain-forming agent and 0.2-0.6 part of a coating agent according to their mass proportions to prepare pulp.

[0009] S2 Wet paper forming: The slurry prepared in step S1 is fed into a web loom, where it is pressed, wrinkled and dried to dry and solidify the paper.

[0010] S3 calendering and winding: the paper after drying in step S2 is sent to the calender, and after calendering, the paper is sent to the winding device for winding, thereby completing the preparation of the low-weight textured base paper.

[0011] Preferably, in the step S1 of preparing the pulp, the bleached bamboo pulp after pulping is prepared by the following method: sending the bleached bamboo pulp board into a pulper for circulating pulping, sending the pulped pulp into a pre-beating pulp pool for pre-beating treatment, and then sending the pulp after pre-beating treatment into a main line disc grinding equipment for pulping treatment, so that the beating degree of the bleached bamboo pulp after pulping is 28-32°SR, and the mass concentration of the bleached bamboo pulp is 3.0-3.5g / L.

[0012] By adopting the above technical scheme, bleached bamboo pulp and bleached coniferous pulp are used, which have high fiber whiteness, high strength, good physical strength indicators of the finished paper, and moderate beating degree. While ensuring the strong strength performance of the paper sheet, the paper sheet has a moderate void ratio and void size, so that the paper sheet has good absorbency and is conducive to post-processing. The mixed use of bamboo pulp and coniferous pulp achieves multiple benefits such as resource utilization, environmental protection, and energy saving, and has high economic and social benefits.

[0013] Preferably, in the step S1 of preparing the pulp, the bleached coniferous pulp after pulping is prepared by the following method: the bleached coniferous pulp is sent to a pulper for circulating pulping, the pulped pulp is sent to a pre-beating pulp tank for pre-beating treatment, and then the pulp after pre-beating treatment is sent to a main line disc refiner for pulping treatment, so that the bleached coniferous pulp after pulping has a beating degree of 38-42°SR and a mass concentration of 4.0-4.5g / L.

[0014] Preferably, the main line disc refiner is composed of five disc refiners connected in series, and the uniformity and fluidity of the slurry are improved by fine grinding and adjusting the quality of the slurry.

[0015] By adopting the above technical solution, the coniferous pulp and bamboo pulp of this nature are fully fibrillated, the dispersion between plant fibers is good, and the manufacturing strength is greater.

[0016] Preferably, in the step S1 of preparing the slurry, the wetting agent is one or a mixture of several of carbamate, phosphate and polyether.

[0017] By adopting the above technical solution, the use of carbamate, phosphate and polyether can promote the wetting and loosening of pulp, improve the hydrolysis and plasticity of fibers, and increase the strength and flatness of paper.

[0018] Preferably, in the step S1 of preparing the slurry, the texture beautifying agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:1-3. The particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh.

[0019] By adopting the above technical solution, the amount of talcum powder and aluminum oxide and the particle size are accurately selected to improve the smoothness and glossiness of the paper surface, fill the tiny depressions on the paper surface, and improve the texture and feel of the paper.

[0020] Preferably, in the pulping step S1, the coating agent is one or a mixture of polyvinyl acid and polyurethane.

[0021] By adopting the above technical solution, poly(ethylene acid) and polyurethane are used to improve the printing performance and abrasion resistance of paper, as well as the subsequent coating and processing performance.

[0022] Preferably, in step S2 of wet paper forming, the pressing and corrugating is performed to control the corrugation dryness to 38-42%.

[0023] Preferably, in step S2 of wet paper forming, the drying is performed by using a drying cylinder, and the drying cylinder is divided into three sections, the temperature of the first section is 60-70°C, the temperature of the second section is 80-90°C, and the temperature of the third section is 70-80°C.

[0024] Preferably, in the calendering and winding step S3, the calendering is soft calendering, the line pressure is 40-44 kN / m, and the basis weight of the low-weight masking base paper is 29-31 g / ㎡.

[0025] In summary, the beneficial technical effects of this application are:

[0026] 1. The present application provides a method for preparing high-quality textured base paper using bamboo pulp and coniferous pulp. By adopting a specific formula, paper with a basis weight of 29-31 g / m2, high strength and good coating effect during post-processing is prepared. The paper has good substitutability and can replace the 38-41 g textured base paper currently produced from all-coniferous wood pulp.

[0027] 2. The present application adopts a mixture of bamboo pulp and coniferous pulp to reduce costs and improve the environmental performance of paper, thereby achieving multiple benefits such as resource utilization, environmental protection, and energy conservation, and has high economic and social benefits. At the same time, the preparation method provided in the present application has the advantages of simple process, easy operation, and low cost, and is suitable for industrial-scale production.

[0028] 3. The low-weight masking base paper of the present application has good strength, glossiness and processability, performs well in subsequent coating and processing, and can be widely used in gift packaging, publishing and printing, environmentally friendly packaging and other fields. DETAILED DESCRIPTION

[0029] The embodiments of the present application will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. In the examples, if specific conditions are not specified, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0030] Example 1

[0031] A method for preparing low-weight masking base paper comprises the following steps:

[0032] The bleached bamboo pulp board and bleached coniferous pulp are respectively sent to the pulper for cyclic pulping, and the pulp after pulping is sent to the pre-beating pulp pool for pre-beating treatment, and then the pulp after pre-beating treatment is sent to the main line disc refiner equipment composed of five disc refiners in series for pulping treatment. The beating degree of the bleached bamboo pulp after pulping is 28°SR, and the mass concentration of the bleached bamboo pulp is 3.0g / L; the beating degree of the bleached coniferous pulp after pulping is 38°SR, and the mass concentration is 4.0g / L.

[0033] S1. Prepare pulp: 60 kg of bleached bamboo pulp after beating, 28 kg of bleached conifer pulp after beating, 0.5 kg of carbamate, 0.5 kg of texture agent and 0.2 kg of polyvinyl acid coating agent are mixed uniformly according to mass fractions to prepare pulp, wherein the texture agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:1. The particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh.

[0034] S2 wet paper forming: the slurry prepared in step S1 is fed into a web loom, and pressed and wrinkled on the web loom. The pressing and wrinkling is controlled to have a wrinkling dryness of 38%, and then dried. The drying is carried out using a drying cylinder, which is divided into three sections. The temperature of the first section is 60°C, the temperature of the second section is 80°C, and the temperature of the third section is 70°C, so that the paper is dried and solidified.

[0035] S3 calendering and winding: the paper after drying in step S2 is sent to the calender, the calendering is soft calendering, the line pressure is 40kN / m, after calendering, the paper is sent to the winding equipment for winding, and the obtained low-weight textured base paper has a weight of 29g / ㎡.

[0036] Example 2

[0037] A method for preparing low-weight masking base paper comprises the following steps:

[0038] The bleached bamboo pulp board and bleached coniferous pulp are respectively sent to the pulper for cyclic pulping, and the pulp after pulping is sent to the pre-beating pulp pool for pre-beating treatment, and then the pulp after pre-beating treatment is sent to the main line disc refiner equipment composed of five disc refiners in series for pulping treatment. The beating degree of the bleached bamboo pulp after pulping is 32°SR, and the mass concentration of the bleached bamboo pulp is 3.5g / L; the beating degree of the bleached coniferous pulp after pulping is 42°SR, and the mass concentration is 4.5g / L.

[0039] S1. Prepare pulp: 70 kg of bleached bamboo pulp, 40 kg of bleached conifer pulp, 1 kg of phosphate, 0.8 kg of texture agent and 0.6 kg of polyurethane are mixed evenly according to mass fractions to prepare pulp; the texture agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:3. The particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh.

[0040] S2 wet paper forming: the slurry prepared in step S1 is fed into a web loom, and pressed and wrinkled on the web loom. The pressing and wrinkling is controlled to have a wrinkling dryness of 42%, and then dried. The drying is carried out using a drying cylinder. The drying cylinder is divided into three sections. The temperature of the first section is 70°C, the temperature of the second section is 90°C, and the temperature of the third section is 80°C, so that the paper is dried and solidified.

[0041] S3 calendering and winding: the paper after drying in step S2 is sent to the calender, the calendering is soft calendering, the line pressure is 44kN / m, after calendering, the paper is sent to the winding equipment for winding, and the obtained low-weight textured base paper has a weight of 31g / ㎡.

[0042] Example 3

[0043] A method for preparing low-weight masking base paper comprises the following steps:

[0044] The bleached bamboo pulp board and bleached coniferous pulp are respectively sent to the pulper for cyclic pulping, and the pulp after pulping is sent to the pre-beating pulp pool for pre-beating treatment, and then the pulp after pre-beating treatment is sent to the main line disc refiner equipment composed of five disc refiners in series for pulping treatment. The beating degree of the bleached bamboo pulp after pulping is 30°SR, and the mass concentration of the bleached bamboo pulp is 3.2g / L; the beating degree of the bleached coniferous pulp after pulping is 40°SR, and the mass concentration is 4.3g / L.

[0045] S1. Prepare pulp: 65kg of bleached bamboo pulp, 33kg of bleached conifer pulp, 0.8kg of polyether, 0.7kg of texture agent, 0.2kg of polyvinyl acid and 0.2kg of polyurethane are mixed evenly according to the mass fractions to prepare pulp; the texture agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:2. The particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh.

[0046] S2 wet paper forming: the slurry prepared in step S1 is fed into a web loom, and pressed and wrinkled on the web loom, and the pressing and wrinkling is controlled to have a wrinkling dryness of 40%, and then dried. The drying is carried out using a drying cylinder, and the drying cylinder is divided into three sections. The temperature of the first section is 65°C, the temperature of the second section is 85°C, and the temperature of the third section is 75°C, so that the paper is dried and solidified.

[0047] S3 calendering and winding: the paper after drying in step S2 is sent to the calender, the calendering is soft calendering, the line pressure is 42kN / m, after calendering, the paper is sent to the winding equipment for winding, and the obtained low-weight textured base paper has a weight of 30g / ㎡.

[0048] Example 4

[0049] A method for preparing low-weight masking base paper comprises the following steps:

[0050] The bleached bamboo pulp board and bleached coniferous pulp are respectively sent to the pulper for cyclic pulping, and the pulp after pulping is sent to the pre-beating pulp pool for pre-beating treatment, and then the pulp after pre-beating treatment is sent to the main line disc refiner equipment composed of five disc refiners in series for pulping treatment. The beating degree of the bleached bamboo pulp after pulping is 30°SR, and the mass concentration of the bleached bamboo pulp is 3.2g / L; the beating degree of the bleached coniferous pulp after pulping is 40°SR, and the mass concentration is 4.3g / L.

[0051] S1. Prepare pulp: 65kg of bleached bamboo pulp, 33kg of bleached conifer pulp, 0.3kg of carbamate, 0.3kg of phosphate, 0.2kg of polyether, 0.7kg of texture agent, 0.2kg of polyvinyl acid, and 0.2kg of polyurethane are mixed evenly according to the mass fractions to prepare pulp; the texture agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:2. The particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh.

[0052] S2 wet paper forming: the slurry prepared in step S1 is fed into a web loom, and pressed and wrinkled on the web loom, and the pressing and wrinkling is controlled to have a wrinkling dryness of 40%, and then dried. The drying is carried out using a drying cylinder, and the drying cylinder is divided into three sections. The temperature of the first section is 65°C, the temperature of the second section is 85°C, and the temperature of the third section is 75°C, so that the paper is dried and solidified.

[0053] S3 calendering and winding: the paper after drying in step S2 is sent to the calender, and the calendering is soft calendering with a line pressure of 42kN / m. After calendering, the paper is sent to the winding equipment for winding, and the obtained low-weight textured base paper has a weight of 30g / m 2 .

[0054] Comparative Example 1

[0055] 41g / m 2 Imported masking paper is used as a control example.

[0056] Performance Testing

[0057] The grained base papers in Examples 1-4 and Comparative Example 1 were sampled and tested respectively. The test results are shown in Table 1.

[0058] Tensile index test: carried out in accordance with GB / T453-2008.

[0059] Coating test: carried out in accordance with GB / T 2590-2008.

[0060] Quantitative determination shall be carried out in accordance with GB / T 451.2-2008.

[0061] The thickness shall be measured in accordance with GB / T 451.3-2008.

[0062] The tightness test shall be carried out in accordance with GB / T 451.3-2008.

[0063] The moisture content shall be determined in accordance with GB / T 462-2008.

[0064] Gloss measurement is carried out in accordance with GB / T8941-2013.

[0065] The absorbency test is carried out in accordance with GB / T4613-2005.

[0066] Table 1

[0067]

[0068]

[0069] It can be seen from Examples 1-4 in Table 1 that the low-weight base paper of the present application has a lower density and good absorbency, which is beneficial to the subsequent absorption of the dipping solution; the low-weight masking base paper has good strength, glossiness, absorbency and coating surface adhesion, which is very beneficial to subsequent coating and processing, and can be widely used in gift packaging, publishing and printing, environmentally friendly packaging and other fields. The overall performance has reached the performance of 41g masking base paper currently produced from all-coniferous wood pulp, and can replace the current 38-41g masking base paper produced from all-coniferous wood pulp.

[0070] From the comparison between Examples 3 and 4 in Table 1, it can be seen that the wet strength agent using a mixture of carbamate, phosphate and polyether has better indicators such as strength and gloss. Carbamate, phosphate and polyether have coordinated properties, which is beneficial to improving the strength and gloss of low-weight base paper and the coating performance of subsequent processing.

[0071] The above embodiments are only used to explain the technical solutions of the present invention rather than to limit the same. Although the above embodiments specifically describe the present invention, relevant technical personnel should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications and equivalent replacements that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing low-weight textured base paper, characterized in that: The following steps are involved: The bleached bamboo pulp board and the bleached conifer are respectively sent to the pulper for circulating pulping, the pulped pulp is sent to the pre-beating pulp tank for pre-beating treatment, and then the pulp after the pre-beating treatment is sent to the main line disc refiner composed of five disc refiners connected in series for pulping treatment, and the beating degree of the bleached bamboo pulp after beating is 30°SR, and the mass concentration of the bleached bamboo pulp is 3.2g / L; the beating degree of the bleached conifer pulp after beating is 40°SR, and the mass concentration is 4.3g / L; S1. Preparing pulp: 65 kg of bleached bamboo pulp after beating, 33 kg of bleached conifer pulp after beating, 0.3 kg of carbamate, 0.3 kg of phosphate, 0.2 kg of polyether, 0.7 kg of texture agent, 0.2 kg of polyvinyl acid, and 0.2 kg of polyurethane are mixed uniformly according to mass fractions to prepare pulp; the texture agent is a composition of talcum powder and aluminum oxide in a mass ratio of 2:2; the particle size of the talcum powder particles is 625-800 mesh, and the particle size of the aluminum oxide particles is 800-1000 mesh; S2 wet paper forming: the slurry prepared in step S1 is fed into a web loom, and pressed and wrinkled on the web loom, and the wrinkling dryness is controlled to be 40%, and then dried. The drying is carried out by a drying cylinder, and the drying cylinder is divided into three sections. The temperature of the first section is 65°C, the temperature of the second section is 85°C, and the temperature of the third section is 75°C, so that the paper is dried and solidified; S3 calendering and winding: the paper dried in step S2 is sent to the calender, and the calendering is soft calendering with a line pressure of 42kN / m. After calendering, the paper is sent to the winding equipment for winding, and the obtained low-weight textured base paper has a weight of 30g / m 2 .

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