Manufacturing method of solvent-free silicone oil type antibacterial release paper

Abstract

The invention discloses a manufacturing method of solvent-free silicone oil type antibacterial release paper, and belongs to the technical field of papermaking, and the method comprises the following steps: S1, cutting needlebush and broadleaf wood into wood chips, cooking, dipping the cooked wood chips in a sulfite solution, taking out, and extruding to remove excessive moisture, so as to obtain a semi-finished product of the solvent-free silicone oil type antibacterial release paper; grinding the wood chips through a disc to obtain sulfite paper pulp; s2, adding filler powder, a wet strength agent, fiber dispersion and water into the sulfite paper pulp to obtain papermaking primary pulp, pulping the papermaking primary pulp, and performing papermaking operation to obtain coarse base paper; s3, coating two surfaces of the coarse base paper with isolation slurry and antibacterial slurry respectively, drying, and carrying out calendering treatment to obtain glassine paper; s4, coating the surface of the antibacterial coating of the glassine paper with a solvent-free silicone oil release agent, and drying to obtain antibacterial release paper; the antibacterial release paper has a good antibacterial effect, and the antibacterial coating and the release layer are firmly attached to each other.

Description

Technical Field

[0001] The invention relates to the technical field of papermaking, and in particular to a method for making solvent-free silicone oil type antibacterial release paper. Background Art

[0002] Release paper is usually required in sanitary products such as sanitary napkins and panty liners. In order to prevent the release paper from becoming a breeding ground for bacteria, it is usually required to have good antibacterial properties. The antibacterial properties of the release paper can improve the safety of these sanitary products. In the production process of release paper, adding antibacterial agents to pulp or coating the surface of base paper with antibacterial agents to form an antibacterial coating can make the release paper have good antibacterial properties. However, adding antibacterial agents to pulp will cause a large amount of antibacterial agents to remain in papermaking white water, resulting in waste of resources and increased costs. Coating the surface of base paper with antibacterial agents to form an antibacterial coating can avoid the waste of antibacterial agents. The antibacterial coating can be arranged on the side of the base paper away from the release agent layer or between the base paper and the release agent layer. The former will expose the antibacterial coating to the environment and easily cause chemical migration, and the latter may affect the adhesion of the release agent to the surface of the base paper. The above-mentioned methods of making the release paper have antibacterial properties all have defects.

[0003] Based on the above situation, a Chinese patent with announcement number CN110886127A discloses a method for preparing an antibacterial and antistatic release paper, which uses fast-growing pine wood as pulp raw material, obtains glassine base paper through papermaking and papermaking, and then soaks the glassine base paper in acetic acid solution, performs corona pretreatment after drying, and coats the mixed release agent on the glassine base paper, and then obtains the antibacterial and antistatic release paper by drying; the mixed release agent includes the following ingredients: food-grade methyl silicone oil, palladium calcium carbonate, antioxidant, chitosan, ultraviolet absorber, antistatic agent and palm oil.

[0004] In the release paper disclosed in the above patent, chitosan is added to the mixed release agent to make the release paper have an antibacterial effect. However, the methyl silicone oil in the mixed release agent can effectively prevent the release layer from the penetration of external moisture and gas, which easily leads to the chitosan inside the release layer being difficult to contact with the outside world and difficult to exert the antibacterial effect of chitosan, thereby resulting in unsatisfactory antibacterial effect of the release paper. Therefore, the release paper still has room for improvement. Summary of the invention

[0005] In view of the technical defects existing in the background technology, the present invention proposes a method for preparing a solvent-free silicone oil type antibacterial release paper, which solves the above technical problems and meets the actual needs. The specific technical solution is as follows: A method for preparing solvent-free silicone oil antibacterial release paper comprises the following steps: S1. Debarking and removing leaves from coniferous and hardwood wood, and then cutting the wood chips into wood chips, placing the wood chips in a cooking container and introducing steam to cook the wood chips, soaking the cooked wood chips in a sulfite solution, taking out the soaked wood chips and removing excess water by squeezing, and grinding the squeezed wood chips to obtain sulfite pulp; S2, adding filler powder, wet strength agent, fiber dispersion and water to sulfite pulp to obtain paper pulp, and then spreading the paper pulp on the surface of the mesh curtain through a headbox after pulping, and shaping the paper prototype through a facing roller, and then squeezing the paper prototype to remove excess water and shape it, and then drying it to obtain a coarse base paper; S3, coating the two sides of the coarse base paper with an isolation slurry and an antibacterial slurry, drying and calendering to obtain glassine paper; wherein the isolation slurry forms an isolation film layer on one side of the coarse base paper after drying, and the antibacterial slurry forms an antibacterial coating on the other side of the coarse base paper after drying, and the glassine paper consists of an isolation film layer, coarse base paper and an antibacterial coating; S4. A solvent-free silicone oil release agent is coated on the surface of the antibacterial coating of the glassine paper and then dried to form a release layer. The glassine paper and the release layer together constitute the antibacterial release paper.

[0006] As a further technical solution of the present invention, the antibacterial slurry includes the following components in mass percentage: 63%~75% aqueous polyacrylic acid emulsion, 3%~6% antibacterial agent, 20%~30% bridging particles, and 0.5%~1% dispersant; the solid content of the aqueous polyacrylic acid emulsion is 10%~20%, and the bridging particles are polyethylene particles with a particle size of 10~50μm.

[0007] As a further technical solution of the present invention, the solvent-free silicone oil release agent includes the following composition by mass percentage: 98%~99% solvent-free silicone oil, 1%~2% bridging aid; the bridging aid is selected from one of silane coupling agent, diisopropylbenzene peroxide, and vinyltrimethoxysilane.

[0008] As a further technical solution of the present invention, the antibacterial agent is selected from one or more of polyhexamethylene guanidine hydrochloride, ε-polylysine, quaternary ammonium salt compounds, inorganic silver ion antibacterial agents, and inorganic zinc ion antibacterial agents; in step S3, the coating dry weight of the antibacterial slurry is 1~2gsm.

[0009] As a further technical solution of the present invention, in step S4, the dry coating amount of the solvent-free silicone oil release agent is 0.5-2 gsm.

[0010] As a further technical solution of the present invention, in step S4, the antibacterial release paper is dried at a temperature of 120-180°C.

[0011] As a further technical solution of the present invention, in step S1, the mass ratio of the wood chips to the sulfite solution is 1:(4-6), and the dry weight of sulfite in the sulfite solution is 20%-40% of the dry weight of the wood chips.

[0012] As a further technical solution of the present invention, the concentration of the papermaking pulp is 4%~8%, the beating degree is 45~60°SR, and the papermaking pulp contains 10%~30% filler powder calculated by the dry weight of wood chips, 0.5%~1.5% wet strength agent, and 0.05%~0.2% fiber dispersant.

[0013] As a further technical solution of the present invention, the filler powder is selected from one or more of calcium carbonate powder, calcium silicate powder, talcum powder, and mica powder.

[0014] As a further technical solution of the present invention, the isolation slurry includes the following components in percentage by mass: 4% to 8% oxidized cassava starch, 0.5% to 2% starch enhancer, 0.2% to 0.5% sodium carboxymethyl cellulose, and the balance is water; in step S3, the coating dry weight of the isolation slurry is 1 to 2 gsm.

[0015] The beneficial effects of the present invention are: The present invention uses sulfite pulp to make glassine paper. After calendering treatment, the glassine paper has a smooth surface and a dense interior. An isolation film layer and an antibacterial coating are respectively provided on both sides of the glassine paper, thereby improving the surface water resistance and antibacterial effect of the glassine paper, and making stress more evenly dispersed during the calendering treatment process to avoid curling of the glassine paper. After a solvent-free silicone oil release agent is coated on the surface of the antibacterial coating of the glassine paper, the antibacterial release paper is obtained, so that the antibacterial release paper has an antibacterial effect while avoiding chemical migration caused by exposure of the antibacterial coating to the environment. In addition, during the drying process, the release layer undergoes a cross-linking reaction with bridging particles in the antibacterial coating under the action of a bridging auxiliary agent, thereby improving the strength of mutual adhesion between the antibacterial coating and the release layer. DETAILED DESCRIPTION

[0016] The implementation mode of the present invention is described below in conjunction with relevant embodiments. The implementation mode of the present invention is not limited to the following embodiments, and the present invention relates to relevant necessary components in the technical field, which should be regarded as the known technology in the technical field and can be known and mastered by the technical personnel in the technical field.

[0017] A method for preparing solvent-free silicone oil antibacterial release paper comprises the following steps: S1. Debarking and removing leaves from coniferous and hardwood wood, and then cutting the wood chips into wood chips, placing the wood chips in a cooking container and introducing steam to cook the wood chips, soaking the cooked wood chips in a sulfite solution, taking out the soaked wood chips and removing excess water by squeezing, and grinding the squeezed wood chips to obtain sulfite pulp; S2, adding filler powder, wet strength agent, fiber dispersant and water to sulfite pulp to obtain paper pulp, and then passing the paper pulp through a headbox to spread it on the surface of a mesh curtain after beating, and then passing it through a finishing roller to shape it to obtain a paper prototype, and then squeezing the paper prototype to remove excess water and shape it, and then drying it to obtain a coarse base paper; S3, coating the two sides of the coarse base paper with an isolation slurry and an antibacterial slurry, drying and calendering to obtain glassine paper; wherein the isolation slurry forms an isolation film layer on one side of the coarse base paper after drying, and the antibacterial slurry forms an antibacterial coating on the other side of the coarse base paper after drying, and the glassine paper consists of an isolation film layer, coarse base paper and an antibacterial coating; S4. A solvent-free silicone oil release agent is coated on the surface of the antibacterial coating of the glassine paper and then dried to form a release layer. The glassine paper and the release layer together constitute the antibacterial release paper.

[0018] The present invention mainly processes coniferous wood and hardwood as raw materials into sulfite pulp and then produces glassine paper and release paper. In step S1, the coniferous wood and hardwood need to be cut after removing bark and leaves. This is because the bark and leaves contain more impurities such as resin and are easy to affect the purity of pulp. The fiber structure of pulp can be optimized and the quality of the paper finally obtained can be better. The coniferous wood and hardwood are cut into wood chips with uniform thickness and then steamed. During the steaming process, the fiber structure inside the wood chips will be softened and the connection structure between the fibers will be destroyed, so that the fibers inside the wood chips are flexible and plastic. Steaming can also kill the fine particles in the wood chips. The wood chips are immersed in a sulfite solution, and the pH value of the sulfite solution is controlled within the range of 6 to 9. The wood chips are heated and boiled to effectively remove impurities such as lignin in the wood chips. The wood chips are then taken out and cleaned, and excess water is removed by a screw extruder and then refined by a disc grinder. The disc grinder exerts a strong mechanical action on the wood chips through a high-speed rotating grinding disc, so that the fibers are further refined and dispersed into single fibers or fiber bundles. An appropriate amount of water is added during the disc grinding process to refine the fibers and improve the disc grinding efficiency. The wood chips are then disc ground to obtain sulfite pulp.

[0019] In step S2, the sulfite pulp can be bleached to a suitable whiteness by using a bleaching agent as required, and then filler powder, a wet strength agent, a fiber dispersant, and water are added to the sulfite pulp to obtain a papermaking stock pulp with a concentration of 4% to 8%. The papermaking stock pulp is beaten by a trough beater, and the beater separates and brooms the pulp fibers by mechanical action, thereby increasing the surface area and bonding force of the fibers. The beating degree of the beater is 45 to 60° SR. During the beating process, the papermaking stock pulp adjusts a suitable beating degree according to the required fiber refinement degree and fiber dispersion degree, and the papermaking stock pulp after beating is completed. The internal fibers and the appropriate degree of dispersion and refinement are achieved; the raw paper pulp that has completed the pulping process is evenly distributed on the surface of the mesh curtain through the headbox, thus forming the initial shape of the paper. Then the finishing roller will flatten and shape its surface to obtain a paper prototype. The shaping treatment of the finishing roller can further improve the flatness and smoothness of the paper prototype, and eliminate possible problems such as fiber orientation stripes. Then, the paper prototype is pressed by a pressing felt to remove excess moisture and improve the internal compactness of the paper prototype, and the surface of the rough base paper after drying can be made smoother and flatter.

[0020] Furthermore, the papermaking pulp contains 10% to 30% filler powder, 0.5% to 1.5% wet strength agent, and 0.05% to 0.2% fiber dispersant calculated based on the dry weight of wood chips; the filler powder added to the papermaking pulp can fill between the fibers of the coarse base paper, reduce the pores of the coarse base paper and improve the surface smoothness of the coarse base paper, and the filler powder can also reduce the fiber dosage in the papermaking pulp, thereby reducing the usage of raw materials such as coniferous wood and hardwood; the wet strength agent is preferably polyamide polyepichlorohydrin resin, which can greatly improve the dry and wet strength of paper, and the beating degree The higher the papermaking pulp, the larger the fiber surface area in the papermaking pulp, the greater the adsorption capacity for the wet strength agent, and the final dry and wet strength of the paper are correspondingly improved. In addition, the wet strength agent has a strong adsorption effect on negatively charged fillers, sizing agents and fine fibers, and has obvious retention and filtration effects in the papermaking process; the fiber dispersant is preferably polyethylene oxide, and the fiber dispersant can shorten the pulping time and improve the softness and strength of the paper after papermaking. The fiber dispersant can also form a network and interact with the suspended solids present in the papermaking pulp to improve the retention rate of fillers and fibers.

[0021] In step S3, an isolation film layer is formed after an isolation slurry is coated on one side of the coarse base paper. This operation is similar to the sizing operation in the common papermaking process. The isolation film layer can significantly improve the water resistance, oil resistance, durability, surface smoothness and other properties of the paper, thereby improving the grade and texture of the paper. After the antibacterial slurry is coated on the other side of the coarse base paper, it will partially penetrate into the interior of the coarse base paper and form an antibacterial coating on its surface. The antibacterial coating kills bacteria through an antibacterial agent with a broad-spectrum bactericidal function to prevent the interior of the paper from becoming a breeding ground for bacteria, so that the final antibacterial release paper meets the antibacterial requirements of sanitary products such as sanitary napkins; after the isolation film layer and the antibacterial coating are formed on both sides of the coarse base paper, the surface is smooth and the interior is dense and uniform through multiple calendering to obtain glassine paper, and the isolation film layer and the antibacterial coating on both sides of the glassine paper can make the stress dispersion more uniform during the calendering process, thereby avoiding the phenomenon of curling of the glassine paper after calendering.

[0022] In step S4, a release layer is formed on the surface of the antibacterial coating of the glassine paper, which can avoid chemical migration caused by the antibacterial coating being exposed to the environment. The antibacterial coating inside the antibacterial release paper can better protect the internal fibers from bacteria, thereby improving the antibacterial effect of the antibacterial release paper.

[0023] As one of the preferred embodiments of the present invention, the antibacterial slurry includes the following components in percentage by mass: 63% to 75% aqueous polyacrylic acid emulsion, 3% to 6% antibacterial agent, 20% to 30% bridging particles, and 0.5% to 1% dispersant; the aqueous polyacrylic acid emulsion is used as the main film-forming component of the antibacterial slurry, the solid content of the aqueous polyacrylic acid emulsion is 10% to 20%, the water in the aqueous polyacrylic acid emulsion is used as the carrier or solvent of the antibacterial slurry, the antibacterial agent, the bridging particles, and the dispersant are respectively dissolved or wrapped, so that the antibacterial slurry forms a uniformly dispersed mixed system, the antibacterial agent makes the antibacterial slurry have an antibacterial effect after being cured into an antibacterial coating, the bridging particles are selected from polyethylene particles with a particle size of 10 to 50 μm, and the bridging particles can be better filled into the downward concave position of the surface of the coarse base paper as a filler, and the dispersant is preferably an alkylbenzene sulfonate, and the dispersant forms a negative charge layer by ionizing anions in water and adsorbing them on the surface of the bridging particles, thereby preventing the bridging particles from agglomerating.

[0024] As one of the preferred embodiments of the present invention, the coating dry weight of the solvent-free silicone oil release agent is 0.5~2gsm, and the solvent-free silicone oil release agent includes the following components in mass percentage: 98%~99% solvent-free silicone oil and 1%~2% bridging aid; the solvent-free silicone oil contains silicone polymer, vinyl silicone oil, cross-linking agent, catalyst, etc., and the silicone polymer and vinyl silicone oil together constitute the basic skeleton of the solvent-free silicone oil. The silicone polymer and vinyl silicone oil can undergo addition reaction with the active hydrogen atoms in the cross-linking agent, so that the solvent-free silicone oil release agent is cured into a release layer, and the catalyst can significantly reduce the activation energy of the reaction and accelerate the cross-linking reaction, thereby shortening the curing time and improving production efficiency.

[0025] Furthermore, the bridging aid is selected from one of silane coupling agent, diisopropylbenzene peroxide and vinyl trimethoxysilane; during the drying and forming process of the antibacterial coating of glassine paper, the moisture in the antibacterial slurry will evaporate and form a polyacrylic acid film, the thickness of the film will be lower than the particle size of the bridging particles and the bridging particles will protrude on the surface of the antibacterial coating; during the calendering process of the glassine paper, the bridging particles will be embedded in the coarse base paper at the bottom due to pressure, and the top will be rolled to be flat; after the solvent-free silicone oil release agent is applied, the drying temperature of the antibacterial release paper is 120-180°C, which can heat the bridging particles into molten polyethylene; at this time, the bridging aid in the solvent-free silicone oil release agent can promote the cross-linking reaction between polyethylene and silicone polymer and vinyl silicone oil to achieve mutual bridging, so that the antibacterial coating and the release layer are bridged by the bridging particles and firmly fixed to each other, thereby improving the adhesion of the release layer to the surface of the antibacterial release paper.

[0026] As one of the preferred embodiments of the present invention, the coating dry weight of the antibacterial slurry is 1-2 gsm, and the antibacterial agent is selected from one or more of polyhexamethylene guanidine hydrochloride, ε-polylysine, quaternary ammonium salt compounds, inorganic silver ion antibacterial agents, and inorganic zinc ion antibacterial agents; wherein polyhexamethylene guanidine hydrochloride inhibits bacterial growth by interfering with cell wall synthesis, and destroys the bacterial cell membrane structure to cause bacterial death; ε-polylysine has obvious inhibitory and killing effects on a variety of microorganisms such as yeast, Gram-positive bacteria and Gram-negative bacteria; quaternary ammonium salt compounds can react with ions in bacteria to achieve an antibacterial effect; inorganic silver ion antibacterial agents combine with cell membranes, cell walls and intracellular proteins, enzymes and other biomacromolecules of microorganisms such as bacteria and fungi through anions, interfere with their normal physiological functions, and thus play a bactericidal role; inorganic zinc ion antibacterial agents destroy their electrolyte balance by adsorbing zinc ions on the surface of bacteria, causing bacterial death, and at the same time, zinc ions can also enter the interior of bacteria to react and combine with cell enzymes, inhibiting the activity of cell enzymes and bacterial reproduction and regeneration.

[0027] As one of the preferred embodiments of the present invention, in step S1, the mass ratio of wood chips to sulfite solution is 1:(4-6), and the dry weight of sulfite in the sulfite solution is 20%-40% of the dry weight of wood chips; the sulfite solution is preferably a sodium sulfite solution, and the sulfite solution is an important raw material for making sulfite pulp. The sulfite ions in the sulfite solution react with the lignin in the wood chips to sulfonate and hydrolyze it to generate water-soluble lignin sulfonate. This chemical reaction effectively dissolves and removes lignin, which is beneficial to improving the quality and strength of paper. In addition, the removal of lignin and the purification of cellulose during the cooking process reduce the colored substances in the pulp, which is beneficial to improving the subsequent bleaching effect of the pulp.

[0028] As one of the preferred embodiments of the present invention, the filler powder is selected from one or more of calcium carbonate powder, calcium silicate powder, talcum powder, and mica powder; the above-mentioned powdered materials are all common papermaking fillers, among which calcium carbonate powder can provide a bright background color for paper and improve the fluffiness, durability, wear resistance and softness of paper, calcium silicate powder can make the color of paper more stable and improve the strength and fluffiness of paper, talcum powder is beneficial to make the surface of paper smoother and improve the wear resistance, chemical stability and softness of paper, and mica powder is beneficial to improve the weather resistance, water resistance and chemical stability of paper; therefore, adding filler powder to papermaking pulp is beneficial to improving the various properties of the final antibacterial release paper.

[0029] As one of the preferred embodiments of the present invention, the isolation slurry includes the following components in percentage by mass: 4% to 8% oxidized cassava starch, 0.5% to 2% starch enhancer, 0.2% to 0.5% sodium carboxymethyl cellulose, and the balance is water; in step S3, the coating dry weight of the isolation slurry is 1 to 2 gsm; the oxidized cassava starch has good adhesion and film-forming properties, so that the isolation slurry can evenly form an isolation film layer on the surface of the coarse base paper, improve the tear resistance of the paper and make the paper smoother and flatter, the starch enhancer can enhance the adhesion, film-forming properties and other properties of the oxidized cassava starch, thereby achieving better coating and film-forming effects at a lower dosage, the sodium carboxymethyl cellulose can improve the water resistance of the paper and make the surface of the paper smooth and delicate, and the sodium carboxymethyl cellulose can enhance the inter-fiber bonding force of the paper, thereby improving the mechanical strength of the paper such as tear resistance and folding resistance.

[0030] The preparation method of the isolation slurry is as follows: pour water into a suitable container, then disperse the oxidized cassava starch and the starch enhancer in the water, heat the oxidized cassava starch to a liquid while stirring to gelatinize the oxidized cassava starch, and add sodium carboxymethyl cellulose after the liquid is fully gelatinized and stir evenly to obtain the isolation slurry.

[0031] In summary, the present invention uses sulfite pulp to make glassine paper. After calendering, the glassine paper has a smooth surface and a dense interior. An isolation film layer and an antibacterial coating are provided on both sides of the glassine paper, respectively, to improve the surface waterproofness and antibacterial effect of the glassine paper, and to make the stress dispersion more uniform during the calendering process to avoid the curling of the glassine paper. After a solvent-free silicone oil release agent is coated on the surface of the antibacterial coating of the glassine paper, the antibacterial release paper is obtained, so that the antibacterial release paper has an antibacterial effect while avoiding chemical migration caused by exposure of the antibacterial coating to the environment. In addition, during the drying process, the release layer undergoes a cross-linking reaction with the bridging particles in the antibacterial coating under the action of a bridging auxiliary agent, thereby improving the strength of mutual adhesion between the antibacterial coating and the release layer.

[0032] The present invention is further described below by way of examples and comparative examples.

[0033] Example 1

[0034] S1. Debarking and removing leaves from coniferous and hardwood wood, and then cutting the wood chips into wood chips, placing the wood chips in a cooking container and introducing steam to cook the wood chips, and immersing the cooked wood chips in a 6% sulfite solution, wherein the mass ratio of the wood chips to the sulfite solution is 1:5, taking out the impregnated wood chips and removing excess water by squeezing, and grinding the squeezed wood chips to obtain sulfite pulp; S2, adding 20% ​​calcium carbonate powder calculated by dry weight of wood chips, 1% polyamide polyepichlorohydrin resin, and 0.1% polyethylene oxide to sulfite pulp to obtain papermaking stock pulp, and then beating the papermaking stock pulp and spreading it on the surface of the mesh curtain through a headbox and shaping it through a facing roller to obtain a paper prototype, wherein the concentration of the papermaking stock pulp is 6% and the beating degree is 60°SR, and then the paper prototype is squeezed to remove excess water and shaped, and then dried to obtain a coarse base paper; S3, coating the two sides of the coarse base paper with an isolation slurry and an antibacterial slurry respectively, drying and calendering to obtain glassine paper; wherein, after the isolation slurry is dried, an isolation film layer is formed on one side of the coarse base paper, and after the antibacterial slurry is dried, an antibacterial coating is formed on the other side of the coarse base paper, and the glassine paper is composed of an isolation film layer, coarse base paper and an antibacterial coating; the coating dry weight of the isolation slurry is 1-2gsm, and the isolation slurry includes the following components by mass percentage: 6% oxidized cassava starch, 1% starch enhancer, 0.3% sodium carboxymethyl cellulose, and the balance is water; the coating dry weight of the antibacterial slurry is 1.5gsm, and the antibacterial slurry includes the following components by mass percentage: 69.3% aqueous polyacrylic acid emulsion with a solid content of 15%, 5% quaternary ammonium salt compound, 25% polyethylene particles with a particle size of 10-50μm, and 0.7% dispersant; S4. After coating the antibacterial coating surface of glassine paper with solvent-free silicone oil release agent, the antibacterial coating surface is heated to 160° C. in an oven and dried to form a release layer. The glassine paper and the release layer together constitute the antibacterial release paper. The coating dry weight of the solvent-free silicone oil release agent is 1.8 gsm, and the solvent-free silicone oil release agent includes the following components by mass percentage: solvent-free silicone oil 98%~99%, silane coupling agent 1%~2%.

[0035] Comparative Example 1 The release paper is obtained based on Example 3 in the specification of a Chinese patent for a method for preparing antibacterial and antistatic release paper (Announcement No.: CN110886127A).

[0036] Comparative Example 2 The difference between this comparative example and the above-mentioned Example 1 is that in step S4, the solvent-free silicone oil release agent contains only solvent-free silicone oil, and the operations and component ratios of the remaining steps are the same.

[0037] Based on the standard document GB / T31402-2015 "Test method for antibacterial performance of plastic surfaces", the antibacterial performance of the release papers of Example 1 and Comparative Example 1 was tested, and the antibacterial rate of the release paper was calculated, wherein the antibacterial rate = (the number of bacteria in the blank sample - the number of bacteria in the antibacterial sample) / the number of bacteria in the blank sample × 100%. The antibacterial rate data are shown in Table 1 below.

[0038]

[0039] Table 1 Analyzing the data in Table 1, during the antibacterial performance test of the release paper of Example 1, the culture solution can penetrate into the interior of the paper well and contact with the antibacterial agent in the antibacterial coating, and the antibacterial agent dissolves in the culture solution to achieve a good antibacterial effect; while in the release paper of Comparative Example 1, the culture solution cannot penetrate into the interior of the release layer to dissolve the chitosan, and can only perform antibacterial activities through the chitosan on the surface of the release layer, thereby affecting the antibacterial effect of the chitosan, and therefore the antibacterial rate of the release paper is low.

[0040] The room temperature peeling force, aging peeling force, residual adhesion, and silicon transfer rate of the centrifugal papers of all the above embodiments and comparisons were tested, and the test results are shown in Table 2 below.

[0041]

[0042] Table 2 It can be seen from the data in Table 2 that in the release paper of Example 1, since the release layer and the antibacterial coating are firmly fixed to each other through a cross-linking reaction, during the peeling test, the silicone oil is not easy to adhere to the tape and be taken away. Therefore, the room temperature peeling force, aging peeling force, and silicon transfer rate of the release paper are relatively low, and the residual adhesion rate is relatively high, achieving a good release effect.

[0043] The above is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a solvent-free silicone oil antibacterial release paper, characterized in that: The following steps are involved: S1. Debarking and removing leaves from coniferous and hardwood wood, and then cutting the wood chips into wood chips, placing the wood chips in a cooking container and introducing steam to cook the wood chips, soaking the cooked wood chips in a sulfite solution, taking out the soaked wood chips and removing excess water by squeezing, and grinding the squeezed wood chips to obtain sulfite pulp; S2, adding filler powder, wet strength agent, fiber dispersion and water to sulfite pulp to obtain paper pulp, and then spreading the paper pulp on the surface of the mesh curtain through a headbox after pulping, and shaping the paper prototype through a facing roller, and then squeezing the paper prototype to remove excess water and shape it, and then drying it to obtain a coarse base paper; S3, coating the two sides of the coarse base paper with an isolation slurry and an antibacterial slurry, drying and calendering to obtain glassine paper; wherein the isolation slurry forms an isolation film layer on one side of the coarse base paper after drying, and the antibacterial slurry forms an antibacterial coating on the other side of the coarse base paper after drying, and the glassine paper consists of an isolation film layer, coarse base paper and an antibacterial coating; S4. A solvent-free silicone oil release agent is coated on the surface of the antibacterial coating of the glassine paper and then dried to form a release layer. The glassine paper and the release layer together constitute the antibacterial release paper.

2. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: The antibacterial slurry includes the following components by mass percentage: 63% to 75% aqueous polyacrylic acid emulsion, 3% to 6% antibacterial agent, 20% to 30% bridging particles, and 0.5% to 1% dispersant; the solid content of the aqueous polyacrylic acid emulsion is 10% to 20%, and the bridging particles are polyethylene particles with a particle size of 10 to 50 μm.

3. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: The solvent-free silicone oil release agent comprises the following components by mass percentage: 98% to 99% solvent-free silicone oil and 1% to 2% bridging aid; the bridging aid is selected from one of a silane coupling agent, diisopropylbenzene peroxide, and vinyltrimethoxysilane.

4. The method for making solvent-free silicone oil type antibacterial release paper according to claim 2, characterized in that: The antibacterial agent is selected from one or more of polyhexamethylene guanidine hydrochloride, ε-polylysine, quaternary ammonium salt compounds, inorganic silver ion antibacterial agents, and inorganic zinc ion antibacterial agents; in step S3, the coating dry weight of the antibacterial slurry is 1-2 gsm.

5. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: In step S4, the dry coating weight of the solvent-free silicone oil release agent is 0.5-2 gsm.

6. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: In step S4, the antibacterial release paper is dried at a temperature of 120-180°C.

7. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: In step S1, the mass ratio of the wood chips to the sulfite solution is 1:(4-6), and the dry weight of sulfite in the sulfite solution is 20%-40% of the dry weight of the wood chips.

8. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: The papermaking pulp has a concentration of 4% to 8% and a beating degree of 45 to 60°SR. The papermaking pulp contains 10% to 30% filler powder, 0.5% to 1.5% wet strength agent, and 0.05% to 0.2% fiber dispersant calculated based on the dry weight of wood chips.

9. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: The filler powder is selected from one or more of calcium carbonate powder, calcium silicate powder, talcum powder and mica powder.

10. The method for making solvent-free silicone oil type antibacterial release paper according to claim 1, characterized in that: The isolation slurry comprises the following components by mass percentage: 4% to 8% oxidized cassava starch, 0.5% to 2% starch enhancer, 0.2% to 0.5% sodium carboxymethyl cellulose, and the balance is water; in step S3, the coating dry weight of the isolation slurry is 1 to 2 gsm.

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