Glossy paper and process for its production

Abstract

This invention relates to the field of papermaking technology, specifically to a glassine paper and its production process. This application aims to solve the problem of how to improve the oil resistance of glassine paper. To this end, the production process of the glassine paper in this application removes gum-like substances from the wood fibers by alkali treatment followed by cooking with the addition of polyether, palm wax, and pentaerythritol stearate. The resulting wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica are then modified with dopamine, further improving the oil resistance of the glassine paper. Furthermore, the glassine paper obtained using the method of this application not only has high density, smoothness, and gloss, but also high strength and good oil resistance, exhibiting excellent performance characteristics.

Description

Technical Field

[0001] This invention relates to the field of papermaking technology, specifically to a glassine paper and its production process. Background Technology

[0002] Glassine paper is an industrial paper produced through processes such as rewetting, supercalendering, and silicone coating. It has a dense, uniform texture, excellent internal strength and transparency, making it a common material for producing barcode labels, self-adhesive labels, tapes, and other sticky industrial products. Glassine paper also possesses certain high-temperature resistance, moisture resistance, and oil resistance, and is generally used in packaging for the food and pharmaceutical industries, such as for release applications like double-sided adhesive tape substrates and laser anti-counterfeiting labels. However, its oil resistance lags significantly behind that of foreign products.

[0003] Accordingly, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0004] To address at least one of the aforementioned problems in the prior art, namely, to solve the problem of how to improve the oil resistance of glassine paper, this application provides a glassine paper manufacturing process, comprising:

[0005] a) Add an alkaline solution with a mass concentration of 2-5% to the wood fiber and cook it at 80-100℃ for 1-2 hours. After cooling to room temperature, add polyether, palm wax and pentaerythritol stearate and cook it at 70-80℃ for 1-2 hours. Then grind and adjust the concentration to obtain wood fiber pulp.

[0006] b) Stir wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica at 30-40℃ for 0.5-1h, then add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 8-9, then add dopamine and react for 5-8h to obtain the mixed pulp.

[0007] c) The mixed pulp is sequentially processed through wire forming, pressing, and drying to obtain glassine base paper;

[0008] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper.

[0009] In the preferred embodiment of the above production process, the production process of the bamboo fiber pulp includes:

[0010] Add a 2-5% alkaline solution to bamboo and cook it at 80-100℃ for 10-20 hours; grind the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 20-25°SR; then grind 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 25-30°SR; then grind 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 30-35°SR.

[0011] The first, second, and third bamboo fiber pulps are mixed to obtain bamboo fiber pulp.

[0012] In the preferred embodiment of the above production process, the mass concentration of the bamboo fiber pulp is 10-15%.

[0013] In the preferred embodiment of the above production process, the silicon dioxide comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of (5-10):(1-2):(0.5-1).

[0014] In the preferred technical solution of the above production process, stirring is carried out during the cooking process, and the stirring speed is 500-1000 r / min.

[0015] In the preferred embodiment of the above production process, the degree of beating of the wood fiber pulp is 35-40°SR; and / or, the mass concentration of the wood fiber pulp is 3-5%.

[0016] In the preferred technical solution of the above production process, the ratio of wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:(0.5-1):(1-2):(2-5):(0.5-1):(1-2):(0.1-0.2).

[0017] In the preferred technical solution of the above production process, the sizing agent used in the sizing process is paraffin emulsion, carboxymethyl cellulose, or styrene-maleic anhydride copolymer.

[0018] In the preferred technical solution of the above production process, the surface adhesive coating amount is 10-30 g / m². 2 .

[0019] This application also discloses a glassine paper, which is produced by the production process described in any of the above preferred technical solutions.

[0020] Those skilled in the art will understand that the glassine paper production process of this application removes gum-like substances from the wood fibers by alkali treatment followed by cooking with polyether, palm wax, and pentaerythritol stearate. The resulting wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica are then modified with dopamine to improve the oil resistance of the glassine paper. Furthermore, the glassine paper obtained using the method of this application not only has high density, smoothness, and gloss, but also high strength and good oil resistance, exhibiting excellent performance characteristics. Detailed Implementation

[0021] This invention provides a process for producing glassine paper, comprising the following:

[0022] a) Add an alkaline solution with a mass concentration of 2-5% to the wood fiber and cook it at 80-100℃ for 1-2 hours. After cooling to room temperature, add polyether, palm wax and pentaerythritol stearate and cook it at 70-80℃ for 1-2 hours. Then grind and adjust the concentration to obtain wood fiber pulp.

[0023] b) Stir wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica at 30-40℃ for 0.5-1h, then add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 8-9, then add dopamine and react for 5-8h to obtain the mixed pulp.

[0024] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0025] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper.

[0026] This application removes gum-like substances from wood fibers by alkali treatment followed by cooking with polyether, palm wax, and pentaerythritol stearate. The resulting wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica are then modified with dopamine to improve the oil resistance of glassine paper. Furthermore, the glassine paper obtained using this method not only has high density, smoothness, and gloss, but also high strength and good oil resistance, exhibiting excellent performance characteristics.

[0027] Regarding step a), in this invention, alkali treatment of the wood fibers disrupts the lignin structure, causing it to separate from the fibers. Subsequent cooking removes the lignin from the wood fibers. The addition of polyether, palm wax, and pentaerythritol stearate further improves fiber dispersibility after cooking, thereby enhancing fiber uniformity and the overall integrity of the paper.

[0028] The method for producing wood fiber is conventional in the field, which includes: processing wood raw materials into small pieces of wood, then steaming the small pieces of wood, followed by hot grinding, drying, and sieving to obtain wood fiber powder, controlling the moisture content of the wood fiber powder to 40-50% (by mass), and finally treating the wood fiber powder with laccase or white rot fungi to obtain wood fiber.

[0029] In an exemplary embodiment, the mass ratio of wood fiber to alkaline solution is 1:(2-5). It should be noted that the alkaline solution in this application can be a sodium hydroxide solution or a potassium hydroxide solution. The mass concentration of the alkaline solution is 2-5%.

[0030] In an exemplary embodiment, the mass ratio of wood fiber to polyether, palm wax, and pentaerythritol stearate is 100:(0.5-1):(0.2-0.4):(0.4-0.7). Furthermore, this application does not limit the polyether, which can be C8-10 alcohol polyoxyethylene ether or propylene glycol polyoxyethylene ether, etc.

[0031] In an exemplary embodiment, the degree of beating of the wood fiber pulp is 35-40°SR, and / or the mass concentration of the wood fiber pulp is 3-5%.

[0032] In an exemplary embodiment, during both cooking processes in step a), stirring is performed at a speed of 500-1000 r / min.

[0033] For step b), in this invention, wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica and silica are modified with dopamine to improve the oil resistance of glassine paper.

[0034] In an exemplary embodiment, the ratio of wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:(0.5-1):(1-2):(2-5):(0.5-1):(1-2):(0.1-0.2).

[0035] In an exemplary embodiment, wood fiber pulp and cellulose can form the skeleton of glassine paper, enabling the glassine paper to have high tensile strength. Adding cellulose to the glassine paper can increase its density. In an exemplary embodiment, this application is not limited to cellulose; it can be microcrystalline cellulose.

[0036] In an exemplary embodiment, chitosan, as a paper reinforcing agent, can improve the tensile strength and tear strength of glassine paper.

[0037] In an exemplary embodiment, the production process of bamboo fiber pulp includes: adding an alkaline solution with a mass concentration of 2-5% to bamboo and cooking it at 80-100°C for 10-20 hours; refining the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 20-25°SR; refining 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 25-30°SR; refining 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 30-35°SR; and mixing the first, second, and third bamboo fiber pulps to obtain the final bamboo fiber pulp. By using first, second, and third fiber pulps with different freenesses, the tensile strength and tear strength of glassine paper can be improved. Furthermore, using bamboo fiber pulp can reduce dependence on wood and increase the sustainability of the paper. It should be noted that the alkaline solution in this application can be a sodium hydroxide solution or a potassium hydroxide solution. The mass concentration of the alkaline solution is 2-5%.

[0038] In an exemplary embodiment, mica fills the gaps in the cellulose, increasing the paper's density and improving its gloss. Silica can improve the paper's strength, durability, and overall quality.

[0039] In an exemplary embodiment, the silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of (5-10):(1-2):(0.5-1). By using different particle sizes for gradation, the roughness of the glassine paper can be improved, thereby increasing the bonding strength between the base paper and the sizing agent during subsequent sizing processes.

[0040] For step c), the papermaking, pressing, and drying are all conventional techniques in this field and will not be described in detail here.

[0041] For step d), the sizing agent used in the sizing process is paraffin emulsion, carboxymethyl cellulose, or styrene-maleic anhydride copolymer. Applying these sizing agents to the base paper improves the oil resistance of glassine paper. Additionally, the surface sizing coating amount is 10-30 g / m². 2 By using the above coating amount, the smoothness of glassine paper can be improved.

[0042] The present invention will be described in conjunction with the following embodiments.

[0043] The polyethers, palm waxes, pentaerythritol stearate, chitosan, cellulose, mica, silica, paraffin emulsions, carboxymethyl cellulose, or styrene-maleic anhydride copolymers used in this application are all commercially available.

[0044] The C8-10 alcohol polyoxyethylene ether and propylene glycol polyoxyethylene ether were both purchased from Haian Petrochemical Plant in Jiangsu Province.

[0045] Palm wax was purchased from Xingtai Yuanwei Chemical Products Sales Co., Ltd.

[0046] Pentaerythritol stearate was purchased from Zhonghe Chemical (Shandong) Co., Ltd., model ZH85116-93-4.

[0047] Chitosan was purchased from Shandong Guante Biotechnology Co., Ltd.

[0048] Microcrystalline cellulose and carboxymethyl cellulose were purchased from Guangzhou Huayu Biotechnology Co., Ltd.

[0049] The mica was purchased from Shijiazhuang Jinli Mining Co., Ltd., with a particle size of 500-1000nm.

[0050] The silica was purchased from Shandong Kason New Materials Co., Ltd.

[0051] In addition, wood fiber is obtained by processing wood into small pieces, then steaming the small pieces, followed by hot grinding, drying, and sieving to obtain wood fiber powder. The moisture content of the wood fiber powder is then controlled to 45%, and finally, white-rot fungi are used to treat the wood fiber powder to obtain wood fiber.

[0052] The paraffin emulsion was purchased from Shanghai Xinnuo Chemical Co., Ltd.

[0053] The styrene-maleic anhydride copolymer was purchased from Dongguan Yushuo New Materials Technology Co., Ltd.

[0054] Dopamine and tris(hydroxymethyl)aminomethane were both purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0055] Example 1

[0056] The production process of glassine paper includes the following steps:

[0057] a) Add a 3% sodium hydroxide solution to wood fibers and cook at 90°C for 1 hour. After cooling to room temperature, add C8 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate and cook at 70°C for 2 hours. Grind the pulp and add water to adjust the concentration of wood fibers to obtain a wood fiber pulp with a mass concentration of 3% and a freeness of 35°SR. The stirring speed for both cooking processes is 500 r / min.

[0058] The mass ratio of wood fiber to alkaline solution, C8 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate is 100:0.5:0.2:0.4.

[0059] b) Stir wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, and silica at 35°C for 0.5 h, add tris(hydroxymethyl)aminomethane to adjust the pH of the entire mixture to 8, then add dopamine and react at 35°C for 7 h to obtain a mixed pulp.

[0060] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:0.5:1:2:1:2:0.2.

[0061] The production process of the fiber pulp includes: adding a 3% sodium hydroxide solution to bamboo and cooking it at 80°C for 20 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 20°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 25°SR; then grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 30°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 10%.

[0062] Silica includes small particles of 0.1-1 μm, 1-5 μm particles, and large particles of 5-20 μm in a mass ratio of 5:1:0.5.

[0063] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0064] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper;

[0065] The sizing agent is a paraffin emulsion with a solid content of 30%, and the surface sizing coating amount is 15g / m². 2 .

[0066] Example 2

[0067] The production process of glassine paper includes the following steps:

[0068] a) Add a 2% sodium hydroxide solution to the wood fiber and cook at 80°C for 2 hours. After cooling to room temperature, add C9 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate and cook at 75°C for 2 hours. Grind the pulp and add water to adjust the concentration of the wood fiber to obtain a wood fiber pulp with a mass concentration of 4% and a freeness of 40°SR. The stirring speed for both cooking processes is 800 r / min.

[0069] The mass ratio of wood fiber to alkaline solution, C9 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate is 100:1:0.3:0.5.

[0070] b) Stir wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, and silica at 30°C for 1 hour, add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 9, then add dopamine and react at 30°C for 8 hours to obtain a mixed pulp.

[0071] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:1:2:5:0.5:1:0.1.

[0072] The production process of the fiber pulp includes: adding a 5% sodium hydroxide solution to bamboo and cooking it at 100°C for 10 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 25°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 30°SR; then grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 35°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 12%.

[0073] Silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of 10:2:0.8.

[0074] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0075] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper;

[0076] The sizing agent is carboxymethyl cellulose with a solid content of 40 wt%, and the surface sizing coating amount is 10 g / m². 2 .

[0077] Example 3

[0078] The production process of glassine paper includes the following steps:

[0079] a) Add a 5% sodium hydroxide solution to wood fibers and cook at 100°C for 1 hour. After cooling to room temperature, add C10 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate and cook at 80°C for 1 hour. Pulp the pulp and add water to adjust the concentration of wood fibers to obtain a wood fiber pulp with a mass concentration of 5% and a freeness of 38°SR. The stirring speed for both cooking processes is 1000 r / min.

[0080] The mass ratio of wood fiber to alkaline solution, C10 alcohol polyoxyethylene ether, palm wax and pentaerythritol stearate is 100:0.7:0.3:0.7;

[0081] b) Stir wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, and silica at 30°C for 1 hour, add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 8.5, then add dopamine and react at 40°C for 5 hours to obtain a mixed pulp.

[0082] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:0.6:1.4:3:0.8:1.5:0.12.

[0083] The production process of the fiber pulp includes: adding a 4% sodium hydroxide solution to bamboo and cooking it at 80°C for 20 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 22°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 28°SR; then grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 32°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 12%.

[0084] Silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of 7:1.2:0.7.

[0085] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0086] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper;

[0087] The sizing agent is a styrene-maleic anhydride copolymer with a solid content of 60 wt%, and the surface coating amount is 20 g / m². 2 .

[0088] Example 4

[0089] The production process of glassine paper includes the following steps:

[0090] a) Add a 4% potassium hydroxide solution to the wood fibers and cook at 85°C for 1.6 hours. After cooling to room temperature, add C9 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate and cook at 75°C for 1.5 hours. Grind the pulp and add water to adjust the concentration of the wood fibers to obtain a wood fiber pulp with a mass concentration of 3.5% and a freeness of 37°SR. The stirring speed during the two cooking processes is 500 r / min.

[0091] The mass ratio of wood fiber to alkaline solution, C9 alcohol polyoxyethylene ether, palm wax and pentaerythritol stearate is 100:0.8:0.25:0.6;

[0092] b) Stir wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, and silica at 35°C for 0.9 h, add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 8.5, then add dopamine and react at 35°C for 7.5 h to obtain a mixed pulp.

[0093] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:0.75:1.5:3.5:0.7:0.75:0.15.

[0094] The production process of the fiber pulp includes: adding a 3% potassium hydroxide solution to bamboo and cooking it at 85°C for 15 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a beating degree of 24°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a beating degree of 28°SR; then grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a beating degree of 33°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 10-15%.

[0095] Silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of 7.5:1.5:0.75.

[0096] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0097] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper;

[0098] The sizing agent is carboxymethyl cellulose with a solid content of 55 wt%, and the surface sizing coating amount is 13 g / m². 2 .

[0099] Example 5

[0100] The production process of glassine paper includes the following steps:

[0101] a) Add a 4.5% potassium hydroxide solution to the wood fibers and cook at 95°C for 1.2 hours. After cooling to room temperature, add propylene glycol polyoxyethylene ether, palm wax, and pentaerythritol stearate and cook at 78°C for 1.5 hours. Grind the pulp and add water to adjust the concentration of the wood fibers to obtain a wood fiber pulp with a mass concentration of 4% and a freeness of 35°SR. The stirring speed during the two cooking processes is 700 r / min.

[0102] The mass ratio of wood fiber to alkaline solution, propylene glycol polyoxyethylene ether, palm wax, and pentaerythritol stearate is 100:0.8:0.3:0.6.

[0103] b) Stir wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, and silica at 35°C for 1 hour, add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 9, then add dopamine and react at 30-40°C for 5 hours to obtain a mixed pulp.

[0104] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:0.7:1.6:4:0.8:1.2:0.15.

[0105] The production process of the fiber pulp includes: adding a 3% potassium hydroxide solution to bamboo and cooking it at 90°C for 15 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 23°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 28°SR; then grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 32°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 12%.

[0106] Silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of 7:1.5:0.7.

[0107] c) The mixed pulp is sequentially processed through wire forming, pressing, and pre-drying to obtain glassine base paper;

[0108] d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper;

[0109] The sizing agent is a paraffin emulsion with a solid content of 40 wt%, and the surface sizing coating amount is 20 g / m². 2 .

[0110] Comparative Example 1

[0111] The only difference from Example 1 is step a):

[0112] Step a) specifically involves:

[0113] A 3% sodium hydroxide solution was added to the wood fibers and cooked at 90°C for 1 hour. After cooling to room temperature, the fibers were cooked at 70°C for 2 hours. The pulp was then ground, and water was added to adjust the concentration of the wood fibers, resulting in a wood fiber pulp with a concentration of 3% and a freeness of 35°SR. The stirring speed during both cooking processes was 500 r / min.

[0114] Comparative Example 2

[0115] The only difference from Example 1 is step a):

[0116] Step a) specifically involves:

[0117] A 3% sodium hydroxide solution was added to the wood fiber and cooked at 90°C for 1 hour. After cooling to room temperature, C8 alcohol polyoxyethylene ether, palm wax, and pentaerythritol stearate were added and cooked at 70°C for 2 hours. The pulp was then ground, and water was added to adjust the concentration of the wood fiber to obtain a wood fiber pulp with a mass concentration of 3% and a freeness of 20°SR. The stirring speed during both cooking processes was 500 r / min.

[0118] Comparative Example 3

[0119] The only difference from Example 2 is step b):

[0120] Step b) specifically refers to:

[0121] Wood fiber pulp, chitosan, bamboo fiber pulp, mica, and silica were stirred at 30°C for 1 hour. Tris(hydroxymethyl)aminomethane was added to adjust the pH of the mixture to 9. Dopamine was then added, and the mixture was reacted at 30°C for 8 hours to obtain a mixed pulp.

[0122] The mass ratio of wood fiber pulp, chitosan, bamboo fiber pulp, mica, silica, and dopamine is 100:1:5:0.5:1:0.1.

[0123] Comparative Example 4

[0124] The only difference from Example 2 is step b):

[0125] Step b) specifically refers to:

[0126] Wood fiber pulp, chitosan, microcrystalline cellulose, mica, and silica were stirred at 30°C for 1 hour. Tris(hydroxymethyl)aminomethane was added to adjust the pH of the mixture to 9. Dopamine was then added, and the mixture was reacted at 30°C for 8 hours to obtain a mixed pulp.

[0127] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, mica, silica, and dopamine is 100:1:2:0.5:1:0.1.

[0128] Comparative Example 5

[0129] The only difference from Example 3 is step b):

[0130] Step b) specifically refers to:

[0131] The production process of the fiber pulp includes: adding a 4% alkaline solution to bamboo and cooking it at 80°C for 20 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 22°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 28°SR; mixing the first and second bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a freeness of 12%.

[0132] Comparative Example 6

[0133] The only difference from Example 3 is step b):

[0134] The production process of the fiber pulp includes: adding a 4% alkaline solution to bamboo and cooking it at 80°C for 20 hours; grinding the cooked bamboo to obtain a second bamboo fiber pulp with a freeness of 28°SR; grinding half of the second bamboo fiber pulp three times to obtain a third bamboo fiber pulp with a freeness of 32°SR; mixing the second and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a freeness of 12%.

[0135] Comparative Example 7

[0136] The only difference from Example 3 is step b):

[0137] The production process of the fiber pulp includes: adding a 4% alkaline solution to bamboo and cooking it at 80°C for 20 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 22°SR; then grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a third bamboo fiber pulp with a freeness of 32°SR; mixing the first and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a freeness of 12% by mass.

[0138] Comparative Example 8

[0139] The only difference from Example 4 is step b):

[0140] Wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, and mica were stirred at 35°C for 0.9 h. Tris(hydroxymethyl)aminomethane was added to adjust the pH of the mixture to 8.5. Dopamine was then added, and the mixture was reacted at 35°C for 7.5 h to obtain a mixed pulp.

[0141] The mass ratio of wood fiber pulp, chitosan, microcrystalline cellulose, bamboo fiber pulp, and mica dopamine is 100:0.75:1.5:3.5:0.7:0.15.

[0142] Comparative Example 9

[0143] The only difference from Example 4 is step b):

[0144] In step b), the silica comprises small particles of 0.1-1 μm and microparticles of 1-5 μm in a mass ratio of 7.5:1.5.

[0145] Comparative Example 10

[0146] The only difference from Example 4 is step b):

[0147] In step b), the silica comprises 1-5 μm particles and 5-20 μm large particles in a mass ratio of 1.5:0.75.

[0148] Comparative Example 11

[0149] The only difference from Example 4 is step b):

[0150] Silica includes small particles of 0.1-1 μm and large particles of 5-20 μm in a mass ratio of 7.5:0.75.

[0151] Comparative Example 12

[0152] The only difference from Example 5 is that step d is omitted.

[0153] Comparative Example 13

[0154] The only difference from Example 5 is step d):

[0155] In step d), the surface adhesive application rate is 5 g / m². 2 .

[0156] Comparative Example 14

[0157] The only difference from Example 5 is step b):

[0158] Step b) specifically involves the production process of the fiber pulp, which includes: adding a 3% potassium hydroxide solution to the bamboo and cooking it at 90°C for 15 hours; grinding the cooked bamboo to obtain a first bamboo fiber pulp with a freeness of 10°SR; grinding 3 / 4 of the first bamboo fiber pulp a second time to obtain a second bamboo fiber pulp with a freeness of 28°SR; grinding 1 / 2 of the second bamboo fiber pulp a third time to obtain a third bamboo fiber pulp with a freeness of 32°SR; mixing the first, second, and third bamboo fiber pulps and adding water to adjust the concentration of the bamboo fiber pulp to obtain a bamboo fiber pulp with a mass concentration of 12%.

[0159] Comparative Example 15

[0160] The only difference from Example 5 is step b):

[0161] Step b) specifically involves silicon dioxide with a small particle size of 0.1-1 μm.

[0162] Comparative Example 16

[0163] The only difference from Example 5 is step b):

[0164] Step b) specifically refers to silicon dioxide with a particle size of 1-5 μm.

[0165] Comparative Example 17

[0166] The only difference from Example 5 is step b):

[0167] Step b) specifically involves silicon dioxide with a large particle size of 5-20 μm.

[0168] The glassine paper prepared in Examples 1-5 and Comparative Examples 1-17 was tested for density, roughness, oleophobicity, tensile strength, tear strength and gloss according to GB / T29282-2024. The results are shown in Table 1.

[0169]

[0170]

[0171] As can be seen from the experimental data in Table 1, the glassine paper prepared in Examples 1-5 is superior to the glassine paper prepared in Comparative Documents 1-17 in terms of density, roughness, oleophobicity, tensile strength, tear strength and gloss.

[0172] Those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the claimed embodiments in the claims of this application can be used in any combination.

[0173] It should be noted that although the detailed steps of the method of this application have been described in detail above, those skilled in the art can combine, split and rearrange the above steps without departing from the basic principles of this application. Such modified technical solutions do not change the basic concept of this application and therefore fall within the protection scope of this application.

[0174] The technical solutions of this application have now been described. However, it will be readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions resulting from these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A glassine paper production process, characterized in that, include: a) Add an alkaline solution with a mass concentration of 2-5% to the wood fiber and cook it at 80-100℃ for 1-2 hours. After cooling to room temperature, add polyether, palm wax and pentaerythritol stearate and cook it at 70-80℃ for 1-2 hours. Then grind and adjust the concentration to obtain wood fiber pulp. b) Stir wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, and silica at 30-40℃ for 0.5-1h, then add tris(hydroxymethyl)aminomethane to adjust the pH of the mixture to 8-9, then add dopamine and react for 5-8h to obtain the mixed pulp. c) The mixed pulp is sequentially processed through wire forming, pressing, and drying to obtain glassine base paper; d) The glassine base paper is sizing the surface, dried, and then calendered to obtain glassine paper; The production process of the bamboo fiber pulp includes: Add an alkaline solution with a mass concentration of 2-5% to the bamboo and steam it at 80-100℃ for 10-20 hours; The steamed bamboo is pulped to obtain a first bamboo fiber pulp with a beat ratio of 20-25°SR; then 3 / 4 of the first bamboo fiber pulp is pulped a second time to obtain a second bamboo fiber pulp with a beat ratio of 25-30°SR; then 1 / 2 of the second bamboo fiber pulp is pulped a third time to obtain a third bamboo fiber pulp with a beat ratio of 30-35°SR. The first, second, and third bamboo fiber pulps are mixed to obtain bamboo fiber pulp; The silica comprises small particles of 0.1-1 μm, microparticles of 1-5 μm, and large particles of 5-20 μm in a mass ratio of (5-10):(1-2):(0.5-1). The degree of beating of the wood fiber pulp is 35-40°SR.

2. The production process according to claim 1, characterized in that, The mass concentration of the bamboo fiber pulp is 10-15%.

3. The production process according to claim 1, characterized in that, Stirring is carried out during the steaming process at a speed of 500-1000 r / min.

4. The production process according to claim 1, characterized in that, The mass concentration of the wood fiber pulp is 3-5%.

5. The production process according to claim 1, characterized in that, The ratio of wood fiber pulp, chitosan, cellulose, bamboo fiber pulp, mica, silica, and dopamine is 100:(0.5-1):(1-2):(2-5):(0.5-1):(1-2):(0.1-0.2).

6. The production process according to claim 1, characterized in that, The sizing agent used in the sizing process is paraffin emulsion, carboxymethyl cellulose, or styrene-maleic anhydride copolymer.

7. The production process according to claim 1, characterized in that, The surface adhesive coating amount is 10-30g / m2.

8. A type of glassine paper, characterized in that, The glassine paper is produced by the production process described in any one of claims 1-7.

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