阅读说明：本技术 一种防水阻燃型瓦楞纸箱及其生产工艺 (Waterproof flame-retardant corrugated carton and production process thereof ) 是由 吕宏伟 朱木根 于 2020-04-06 设计创作，主要内容包括：本发明公开了一种防水阻燃型瓦楞纸箱,由防水阻燃瓦楞纸制成,该瓦楞纸包括基纸和涂覆于基纸表面的功能涂层,基纸经过浸渍液浸渍改性处理；该瓦楞纸箱的生产工艺如下：第一步、将基纸浸渍于浸渍液中,超声后干燥；第二步、将涂料均匀涂覆于浸渍后的基纸表面,固化、瓦楞辊加工；第三步、钉箱。本发明通过浸渍液浸渍处理基纸,浸渍液中的有效成分与基纸纤维具有较强的结合力,不仅能够充分发挥阻燃性能,而且能够形成交联的网络结构,提高基纸的力学性能；经过功能涂料的涂覆,使瓦楞纸具备良好的防水性能；并且,浸渍液、功能涂料的各个原料均是环保原料,基纸本身是采用普通木材制成的,因此,得到的瓦楞纸具有易降解的特性,符合环保要求。(The invention discloses a waterproof flame-retardant corrugated case which is made of waterproof flame-retardant corrugated paper, wherein the corrugated paper comprises base paper and a functional coating coated on the surface of the base paper, and the base paper is subjected to impregnation modification treatment by an impregnation liquid; the production process of the corrugated case comprises the following steps: firstly, dipping base paper in a dipping solution, and drying after ultrasonic treatment; step two, coating the coating on the surface of the impregnated base paper uniformly, curing and processing by a corrugating roller; and thirdly, nailing the box. According to the invention, the base paper is impregnated by the impregnating solution, so that the effective components in the impregnating solution and the base paper fibers have strong binding force, the flame retardant property can be fully exerted, a cross-linked network structure can be formed, and the mechanical property of the base paper is improved; the corrugated paper has good waterproof performance through coating of the functional coating; moreover, the raw materials of the impregnating solution and the functional coating are environment-friendly raw materials, and the base paper is made of common wood, so that the obtained corrugated paper has the characteristic of easy degradation and meets the requirement of environmental protection.)

1. A waterproof flame-retardant corrugated case is made of waterproof flame-retardant corrugated paper and is characterized in that the waterproof flame-retardant corrugated paper comprises base paper and a functional coating coated on the surface of the base paper, wherein the base paper is subjected to impregnation modification treatment by impregnation liquid;

the corrugated carton is manufactured by the following steps:

step one, pouring the impregnation liquid into a glass dish, heating the impregnation liquid to 50-55 ℃, impregnating the base paper into the impregnation liquid, ultrasonically impregnating for 10-12s, taking out the base paper, and drying in a hot constant-temperature air drying oven at 60 ℃ for 50-60min to obtain the impregnated base paper;

secondly, coating the coating on the surface of the impregnated base paper uniformly, wherein the coating weight is 30-50g/m²Standing at room temperature for 10-15min, curing at 105 deg.C for 60-70min, and processing with corrugating roller to obtain corrugated paper;

and thirdly, nailing the corrugated paper through a box nailing machine to obtain the corrugated paper box.

2. The waterproof and flame-retardant corrugated carton according to claim 1, wherein the impregnation liquid is prepared by the following method:

slowly adding silica sol into NaOH solution at constant temperature of 75 ℃ under the condition of magnetic stirring at a speed of 80-90r/min, magnetically stirring for 50-60min after adding, and then adding methyl cellulose and nano TiO₂And continuously stirring for 30-40min to obtain the impregnation liquid.

3. The waterproof and flame-retardant corrugated carton according to claim 2, wherein the NaOH solution comprises 30% by mass of silica sol, NaOH solution, methylcellulose and nano TiO₂The ratio of the dosage of the components is 10:2:0.5: 0.2.

4. The waterproof and flame retardant corrugated carton according to claim 1, wherein the coating material for the functional coating layer is prepared by the following method:

(1) adding polylactone polyol and succinic anhydride into a three-neck flask, adding a proper amount of organic tin catalyst, reacting for 24 hours at normal temperature, adding N-aminoethyl-3-aminopropyltriethoxysilane, raising the temperature to 75-80 ℃, and reacting for 10 hours to obtain modified polyurethane resin;

wherein the mass ratio of polylactone polyol to succinic anhydride is 1.2: 1; the adding amounts of the N-aminoethyl-3-aminopropyltriethoxysilane and the organotin catalyst are respectively 4 percent and 0.1 percent of the mass of the system;

(2) adding the modified polyurethane resin into an acetic acid aqueous solution with the mass fraction of 5%, adding a small amount of methanol, and magnetically stirring for 3 hours to obtain a modified polyurethane emulsion;

the mass ratio of the modified polyurethane resin to the acetic acid aqueous solution to the methanol is 10:7: 0.1;

(3) adding nano-cellulose and chitosan into the modified polyurethane emulsion, and magnetically stirring for 3 hours to obtain a coating;

the addition amounts of the nano-cellulose and the chitosan are respectively 5 percent and 3 percent of the mass of the modified polyurethane emulsion.

5. The production process of the waterproof flame-retardant corrugated case according to claim 1, characterized by comprising the steps of:

step one, pouring the impregnation liquid into a glass dish, heating the impregnation liquid to 50-55 ℃, impregnating the base paper into the impregnation liquid, ultrasonically impregnating for 10-12s, taking out the base paper, and drying in a hot constant-temperature air drying oven at 60 ℃ for 50-60min to obtain the impregnated base paper;

secondly, coating the coating on the surface of the impregnated base paper uniformly, wherein the coating weight is 30-50g/m²Standing at room temperature for 10-15min, curing at 105 deg.C for 60-70min, and processing with corrugating roller to obtain corrugated paper;

and thirdly, nailing the corrugated paper through a box nailing machine to obtain the corrugated paper box.

Technical Field

The invention belongs to the field of corrugated cartons, and particularly relates to a waterproof flame-retardant corrugated carton and a production process thereof.

Background

Corrugated paper is a plate-shaped object formed by bonding corrugated paper formed by processing corrugated rods and liner paper, has the advantages of low cost, light weight, easy processing, high strength, excellent printing adaptability, convenient storage and transportation and the like, and the corrugated paper box processed by the corrugated paper can be used for packaging food or digital products and is widely used.

The corrugated paper is easy to damp due to the fact that the main components of the corrugated paper are paper fibers with strong water absorption, when the corrugated paper is applied to food materials needing dry storage, the waterproof performance of the corrugated paper affects the quality and the quality guarantee period of materials in a package, the existing corrugated paper box is usually formed by directly coating the waterproof materials on the surface of the corrugated paper, but the waterproof durability of the coated waterproof materials is poor, the situation of water seepage is easy to occur when the corrugated paper is soaked in water for a long time, complete waterproof cannot be achieved, only the surface is slightly waterproof, and when the corrugated paper box is stored in a humid environment or is wetted by rainwater in the transportation process, the internal water seepage is easy to cause, and the quality of the internal materials. In addition, because the main component of the corrugated board is plant cellulose, the corrugated board is dehydrated and oxidized along with the rise of temperature when being heated, and the oxygen index of the corrugated board at normal temperature is only 15 percent, which belongs to inflammable products. In the storage and transportation process of electricity merchant, commodity circulation, express delivery trade, a large amount of corrugated boxes are piled up, have great fire control potential safety hazard.

Disclosure of Invention

The invention aims to provide a waterproof flame-retardant corrugated case and a production process thereof, the corrugated case is made of specially-made waterproof flame-retardant corrugated paper, the corrugated paper comprises base paper and a functional coating, the base paper is impregnated by impregnating solution, active ingredients in the impregnating solution can be distributed in the base paper, and the impregnating solution has stronger binding force with base paper fibers, so that the flame-retardant performance can be fully exerted, a cross-linked network structure can be formed, and the mechanical property of the base paper is improved; by coating the functional coating, not only can a compact surface coating with a hydrophobic function be formed, but also the hydrophobic property of the surface of the base paper body can be improved, so that the corrugated paper has good waterproof property; the flame-retardant corrugated paper with the waterproof function is obtained, and has wide application space in the field of packaging; moreover, the raw materials of the impregnating solution and the functional coating are environment-friendly raw materials, the use of toxic solvents is avoided in the preparation process, and the base paper is made of common wood, so that the obtained corrugated paper has the characteristic of easy degradation and meets the requirement of environmental protection.

The purpose of the invention can be realized by the following technical scheme:

a waterproof flame-retardant corrugated case is made of waterproof flame-retardant corrugated paper, wherein the waterproof flame-retardant corrugated paper comprises base paper and a functional coating coated on the surface of the base paper, and the base paper is subjected to impregnation modification treatment by using an impregnation liquid;

the corrugated carton is manufactured by the following steps:

step one, pouring the impregnation liquid into a glass dish, heating the impregnation liquid to 50-55 ℃, impregnating the base paper into the impregnation liquid, ultrasonically impregnating for 10-12s, taking out the base paper, and drying in a hot constant-temperature air drying oven at 60 ℃ for 50-60min to obtain the impregnated base paper;

secondly, coating the coating on the surface of the dipped base paper uniformly,the coating weight is 30-50g/m²Standing at room temperature for 10-15min, curing at 105 deg.C for 60-70min, and processing with corrugating roller to obtain corrugated paper;

and thirdly, nailing the corrugated paper through a box nailing machine to obtain the corrugated paper box.

Further, the impregnation liquid is prepared by the following method:

slowly adding silica sol into NaOH solution at constant temperature of 75 ℃ under the condition of magnetic stirring at a speed of 80-90r/min, magnetically stirring for 50-60min after adding, and then adding methyl cellulose and nano TiO₂And continuously stirring for 30-40min to obtain the impregnation liquid.

Further, the mass fraction of the NaOH solution is 30%, and the NaOH solution comprises silica sol, NaOH solution, methyl cellulose and nano TiO₂The ratio of the dosage of the components is 10:2:0.5: 0.2.

Further, the coating used for the functional coating is prepared by the following method:

(1) adding polylactone polyol and succinic anhydride into a three-neck flask, adding a proper amount of organic tin catalyst, reacting for 24 hours at normal temperature, adding N-aminoethyl-3-aminopropyltriethoxysilane, raising the temperature to 75-80 ℃, and reacting for 10 hours to obtain modified polyurethane resin;

wherein the mass ratio of polylactone polyol to succinic anhydride is 1.2: 1; the adding amounts of the N-aminoethyl-3-aminopropyltriethoxysilane and the organotin catalyst are respectively 4 percent and 0.1 percent of the mass of the system;

(2) adding the modified polyurethane resin into an acetic acid aqueous solution with the mass fraction of 5%, adding a small amount of methanol, and magnetically stirring for 3 hours to obtain a modified polyurethane emulsion;

the mass ratio of the modified polyurethane resin to the acetic acid aqueous solution to the methanol is 10:7: 0.1;

(3) adding nano-cellulose and chitosan into the modified polyurethane emulsion, and magnetically stirring for 3 hours to obtain a coating;

the addition amounts of the nano-cellulose and the chitosan are respectively 5 percent and 3 percent of the mass of the modified polyurethane emulsion.

A production process of a waterproof flame-retardant corrugated carton comprises the following steps:

step one, pouring the impregnation liquid into a glass dish, heating the impregnation liquid to 50-55 ℃, impregnating the base paper into the impregnation liquid, ultrasonically impregnating for 10-12s, taking out the base paper, and drying in a hot constant-temperature air drying oven at 60 ℃ for 50-60min to obtain the impregnated base paper;

secondly, coating the coating on the surface of the impregnated base paper uniformly, wherein the coating weight is 30-50g/m²Standing at room temperature for 10-15min, curing at 105 deg.C for 60-70min, and processing with corrugating roller to obtain corrugated paper;

and thirdly, nailing the corrugated paper through a box nailing machine to obtain the corrugated paper box.

The invention has the beneficial effects that:

the invention adopts the impregnating solution to perform the impregnation modification treatment on the base paper, and the TiO is used for impregnating the base paper by the impregnating solution₂The surface contains more hydroxyl, and the doped TiO is doped under the action of hydrogen bonds and electrostatic attraction₂Can be adsorbed on the surface of paper fiber; the-Si-O-Si-chain of the silica sol in the impregnating solution can generate homolytic and heterolytic cracking in an alkaline environment to respectively form-Si-, -SiO and-Si⁺，-Si-O^-All the components have strong reaction activity, can generate H & OH with strong photocatalytic activity in aqueous solution, can react with organic matters (paper fibers) containing hydroxyl-OH in a fiber board, and can ensure that the impregnation liquid is firmly combined with the base paper fibers; meanwhile, in an alkaline environment, the formed-Si-OH and-Ti-OH can form a silicon chain network structure with a cross-linking structure under the action of hydrogen bonds, so that the impregnation liquid forms the cross-linking network structure in the base paper, and the silicon component and the nano TiO in the impregnation liquid can be enhanced₂The bonding fastness with the base paper, and the crosslinked network structure can improve the mechanical property of the base paper; TiO 2₂The paper is used as an opacifier, has excellent high-temperature resistance, can continuously generate a shading effect in a system, and further improves the flame retardant property of the base paper; the siliceous component is an intumescent flame retardant and is attached to the surface of the base paper fiber in an intumescent manner in the combustion process, so that the purpose of flame retardance is achieved; and nano TiO₂Can be used as a kind in the combustion processThe cocatalyst can promote siliceous materials to generate more reticular cross-linked structures, so that the flame retardant property is further improved; in addition, after the base paper is subjected to impregnation treatment, suspended particles in the impregnation liquid can fill gaps in the base paper, so that the stiffness of the base paper is improved, and the methyl cellulose has a thickening effect, can also increase the stiffness of the base paper, and has a promoting effect on strength indexes in the aspects of compression resistance and pressure resistance;

according to the invention, the surface of the base paper is coated with a layer of coating to form a functional coating, the coating adopts modified polyurethane emulsion as a film forming matrix, a silane chain grafted on a modified polyurethane resin molecular chain forms Si-OH after hydrolysis in the step (2), and can react with-OH on the surfaces of the nano-cellulose and the chitosan to form Si-O-C bonds, so that the inorganic filler is combined with the film forming matrix in a chemical bond mode, namely, the compatibility between the nano-cellulose, the chitosan and the film forming matrix is increased, the interaction is enhanced, the nano-cellulose and the chitosan are uniformly distributed in the coating, the filler effect is stably exerted, and the compactness and the mechanical property of the coating are improved; in addition, the interaction of the polyurethane molecular chain and the filler can reduce the number of hydrophilic groups-OH on the surfaces of the nano-cellulose and the chitosan, and meanwhile, due to the hydrophobicity of the polymer molecular chain, the coating has excellent hydrophobic property after forming a coating; in addition, the silanol groups are condensed to form a polymer with Si-O-Si bonds on one hand, and generate etherification reaction with-OH on the surfaces of the nano-cellulose and the chitosan to generate Si-O-C bonds on the other hand, so that the coating becomes a more compact three-dimensional network structure, the compactness of the coating is improved, and the barrier property and the mechanical property of the base paper are obviously improved; in addition, the silanol groups can also react with-OH on fibers on the surface of the base paper, so that the adhesive force of the coating is improved, the-OH content on the surface of the base paper is reduced, and the hydrophobic property of the base paper body is improved;

according to the invention, the base paper is impregnated by the impregnating solution, so that the active ingredients in the impregnating solution can be distributed in the base paper, and have strong binding force with base paper fibers, thereby not only fully exerting the flame retardant property, but also forming a cross-linked network structure and improving the mechanical property of the base paper; by coating the functional coating, not only can a compact surface coating with a hydrophobic function be formed, but also the hydrophobic property of the surface of the base paper body can be improved, so that the corrugated paper has good waterproof property; the flame-retardant corrugated paper with the waterproof function is obtained, and has wide application space in the field of packaging; moreover, the raw materials of the impregnating solution and the functional coating are environment-friendly raw materials, the use of toxic solvents is avoided in the preparation process, and the base paper is made of common wood, so that the obtained corrugated paper has the characteristic of easy degradation and meets the requirement of environmental protection.

Detailed Description

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

A waterproof flame-retardant corrugated case is made of waterproof flame-retardant corrugated paper, wherein the corrugated paper comprises base paper and a functional coating coated on the surface of the base paper, and the base paper is subjected to impregnation modification treatment by an impregnation liquid;

the impregnation liquid is prepared by the following method:

slowly adding silica sol into NaOH solution (30 wt%) under the conditions of constant temperature of 75 deg.C and magnetic stirring of 80-90r/min, magnetically stirring for 50-60min, and adding methylcellulose and nano TiO₂Continuously stirring for 30-40min to obtain a steeping fluid;

silica sol, NaOH solution, methyl cellulose and nano TiO₂The dosage ratio of the components is 10:2:0.5: 0.2;

after the base paper is impregnated by the impregnating solution, the base paper is impregnated by TiO₂The surface contains more hydroxyl, and the doped TiO is doped under the action of hydrogen bonds and electrostatic attraction₂Can be adsorbed on the surface of paper fiber; the-Si-O-Si-chain of the silica sol in the impregnating solution can generate homolytic and heterolytic cracking in an alkaline environment to respectively form-Si-, -SiO and-Si⁺，-Si-O^-All have extremely strong reaction activity and can generate strong photocatalysis in aqueous solutionThe active H & OH can react with the organic matter (paper fiber) containing hydroxyl-OH in the fiber board, so that the impregnation liquid can be firmly combined with the base paper fiber; meanwhile, in an alkaline environment, the formed-Si-OH and-Ti-OH can form a silicon chain network structure with a cross-linking structure under the action of hydrogen bonds, so that the impregnation liquid forms the cross-linking network structure in the base paper, and the silicon component and the nano TiO in the impregnation liquid can be enhanced₂The bonding fastness with the base paper, and the crosslinked network structure can improve the mechanical property of the base paper; TiO 2₂The paper is used as an opacifier, has excellent high-temperature resistance, can continuously generate a shading effect in a system, and further improves the flame retardant property of the base paper; the siliceous component is an intumescent flame retardant and is attached to the surface of the base paper fiber in an intumescent manner in the combustion process, so that the purpose of flame retardance is achieved; and nano TiO₂Can be used as a cocatalyst in the combustion process, can promote siliceous materials to generate more reticular cross-linked structures, and further improve the flame retardant property; in addition, after the base paper is subjected to impregnation treatment, suspended particles in the impregnation liquid can fill gaps in the base paper, so that the stiffness of the base paper is improved, and the methyl cellulose has a thickening effect, can also increase the stiffness of the base paper, and has a promoting effect on strength indexes in the aspects of compression resistance and pressure resistance;

the paint used for the functional coating is prepared by the following method:

(1) adding polylactone polyol and succinic anhydride into a three-neck flask, adding a proper amount of organic tin catalyst, reacting for 24 hours at normal temperature, adding N-aminoethyl-3-aminopropyltriethoxysilane, raising the temperature to 75-80 ℃, and reacting for 10 hours to obtain modified polyurethane resin;

wherein the mass ratio of polylactone polyol to succinic anhydride is 1.2: 1; the adding amounts of the N-aminoethyl-3-aminopropyltriethoxysilane and the organotin catalyst are respectively 4 percent and 0.1 percent of the mass of the system;

succinic anhydride and terminal hydroxyl-OH of polylactone polyol are subjected to esterification reaction, so that the succinic anhydride is grafted on a polycaprolactone polyol molecular chain in a ring-opening manner, carboxyl-COOH is introduced on an organic polymer molecular chain, and the introduced-COOH functional group and amino-NH on aminopropyltriethoxysilane₂Take place ofCondensation reaction to form-CO-NH-bond and graft N-aminoethyl-3-aminopropyltriethoxysilane on polymer chain to form modified polyurethane resin;

(2) adding the modified polyurethane resin into an acetic acid aqueous solution with the mass fraction of 5%, adding a small amount of methanol, and magnetically stirring for 3 hours to obtain a modified polyurethane emulsion;

the mass ratio of the modified polyurethane resin to the acetic acid aqueous solution to the methanol is 10:7: 0.1;

(3) adding nano-cellulose and chitosan into the modified polyurethane emulsion, and magnetically stirring for 3 hours to obtain a coating;

the addition amounts of the nano-cellulose and the chitosan are respectively 5 percent and 3 percent of the mass of the modified polyurethane emulsion;

the silane chain grafted on the molecular chain of the modified polyurethane resin forms Si-OH after hydrolysis in the step (2), and can react with-OH on the surfaces of the nano-cellulose and the chitosan to form Si-O-C bonds, so that the inorganic filler is combined with the film-forming matrix in a chemical bond mode, namely, the compatibility and interaction among the nano-cellulose, the chitosan and the film-forming matrix are increased, the nano-cellulose and the chitosan are uniformly distributed in the coating, the filler effect is stably exerted, and the compactness and the mechanical property of the coating are improved; in addition, the interaction of the polyurethane molecular chain and the filler can reduce the number of hydrophilic groups-OH on the surfaces of the nano-cellulose and the chitosan, and meanwhile, due to the hydrophobicity of the polymer molecular chain, the coating has excellent hydrophobic property after forming a coating; in addition, the silanol groups are condensed to form a polymer with Si-O-Si bonds on one hand, and generate etherification reaction with-OH on the surfaces of the nano-cellulose and the chitosan to generate Si-O-C bonds on the other hand, so that the coating becomes a more compact three-dimensional network structure, the compactness of the coating is improved, and the barrier property and the mechanical property of the base paper are obviously improved; in addition, the silanol groups can also react with-OH on fibers on the surface of the base paper, so that the adhesive force of the coating is improved, the-OH content on the surface of the base paper is reduced, and the hydrophobic property of the base paper body is improved;

the production process of the corrugated case comprises the following steps:

step one, pouring the impregnation liquid into a glass dish, heating the impregnation liquid to 50-55 ℃, impregnating the base paper into the impregnation liquid, ultrasonically impregnating for 10-12s, taking out the base paper, and drying in a hot constant-temperature air drying oven at 60 ℃ for 50-60min to obtain the impregnated base paper;

secondly, coating the coating on the surface of the impregnated base paper uniformly, wherein the coating weight is 30-50g/m²Standing at room temperature for 10-15min, curing at 105 deg.C for 60-70min, and processing with corrugating roller to obtain corrugated paper;

and thirdly, nailing the corrugated paper through a box nailing machine to obtain the corrugated paper box.