CN116289328B

CN116289328B - High water resistance food packaging body paper

Info

Publication number: CN116289328B
Application number: CN202310224634.4A
Authority: CN
Inventors: 胡丁根; 杨刚; 梁成; 陈旭; 姚华; 陆佩静
Original assignee: Huabang Gulou New Material Co ltd
Current assignee: Huabang Gulou New Material Co ltd
Priority date: 2023-03-10
Filing date: 2023-03-10
Publication date: 2023-12-08
Anticipated expiration: 2043-03-10
Also published as: CN116289328A

Abstract

The application provides high-water-resistance food packaging base paper which comprises a surface pulp layer and a bottom pulp layer, wherein the surface pulp layer comprises the following raw materials in parts by weight: 40-60 parts of wood pulp; 20-30 parts of tough leather pulp; 3-8 parts of composite water-resistant fiber; 3-5 parts of wet strength agent; 1-3 parts of dispersing agent; 0.5-2 parts of hydrophobic modifier; 0.2 to 0.5 portion of defoaming agent; 2-5 parts of liquid paraffin; 0.01 to 0.02 portion of polysaccharide compound; 0.5 to 1 part of stearic acid; 0.5-2 parts of layered silicate; the high water resistance food packaging base paper has the advantages of good water resistance, simple preparation, environment friendliness, health and environment friendliness.

Description

High water resistance food packaging body paper

Technical Field

The application relates to the field of food packaging paper, in particular to high-water-resistance food packaging base paper.

Background

In the packaging industry, food packaging accounts for almost seventy percent, the selection of packaging materials is very strict, the physical health of consumers and the effective storage of foods are directly related, and common food packaging materials mainly comprise plastics and food packaging papers. Although the plastic packaging material has the advantages of low cost, portability and good barrier property, the plastic packaging material has the defects of difficult degradation and easy migration of chemical components, and the development is limited by a plurality of factors; compared with plastic products, the food packaging paper has the characteristics of environmental protection, multiple functions, safety, reliability, convenient use and the like, and becomes a main material of food packaging such as fast food takeout and the like.

In general, the food packaging paper must meet food sanitation standards, and must have good barrier properties (water and oil resistance) and necessary mechanical strength. At present, the water and oil resistant food packaging paper is mainly used for blocking water and oil by spraying PE or PP plastic films or applying Tu Fangshui oil resistant agents on the surface of paper. However, PE or PP coated products have the problems of non-degradability, non-repulpability, difficult recovery and the like. In addition, although the oil-proofing agent applied to the surface of paper has good oil-proofing effect, the oil-proofing agent such as fluorine-containing oil-proofing agent can form PFOA (ammonium perfluorooctanoate) and PFOS (perfluorooctane sulfonate) by molecular chain breakage under high-temperature environment, and the substances can enter human body along with food chain, so that various diseases such as cancer, thyroid diseases, immune system inhibition and the like are caused, the use of the fluorine-containing water-proofing and oil-proofing agent is forbidden in European and American countries at present, and the use of the fluorine-containing water-proofing and oil-proofing agent is limited in China.

Along with the enhancement of environmental protection consciousness and the upgrading of food consumption concepts, the green, safe and standardized food packaging materials become the focus of attention of management departments and consumers. Therefore, the non-laminated high-performance waterproof and oilproof food packaging paper has wide development prospect from the aspect of meeting the requirements of food safety and environmental protection. For the non-laminated high-performance waterproof and oilproof food packaging paper, the performance of the base paper has a direct influence on the performance of the final product, and currently, in all aspects of the performance of the food packaging base paper, the poor water resistance is one of the main defects of the base paper, so that the application of the base paper in food packaging with higher water content is greatly limited, the substitution of the base paper for laminated food packaging paper becomes very difficult, and the base paper becomes a key core technical problem of the food packaging paper base material industry.

Disclosure of Invention

The application designs a high-water-resistance food packaging base paper to solve the technical problems of poor water resistance and limited application of the existing food packaging base paper.

In order to solve the problems, the application discloses high-water-resistance food packaging base paper, which comprises a surface pulp layer and a bottom pulp layer, wherein the surface pulp layer comprises the following raw materials in parts by weight:

further, the thickness ratio of the primer layer to the topcoat layer is (3-10): 1.

Further, the bottom slurry layer comprises the following raw materials in parts by weight:

further, the wet strength agent is acrylamide grafted copolymer starch.

Further, the antibacterial agent is one or more of quaternary ammonium salt antibacterial agent, biguanide antibacterial agent, alcohol antibacterial agent, phenol antibacterial agent or pyridine antibacterial agent.

Further, the composite water-resistant fiber comprises a main fiber and branch fibers embedded in the main fiber.

Further, the length of the main fiber is 2-10 mm; the length of the branch fiber is 0.1-3 mm; the diameter of the main fiber is 0.2-0.5 mm; the diameter of the branch fiber is 0.1-0.3 mm.

Further, the branch fiber is one or more of artificial chopped fiber, carbon fiber, asbestos fiber or brucite fiber.

Further, the preparation method of the composite water-resistant fiber comprises the following steps:

p1, adding 10 to 20 weight parts of polyvinylidene fluoride, 50 to 80 weight parts of solvent and 3 to 5 weight parts of additive into a stirring kettle respectively, and stirring for 10 to 20 minutes at the temperature of between 60 and 80 ℃ for later use;

p2, adding 13-25% of branch fibers by volume into the mixed solution obtained in the step P1, fully and uniformly stirring, and standing for 24-48 hours for defoaming to obtain spinning solution;

p3, adopting purified water as core liquid, filling the core liquid into a central tube of a tubular hollow fiber spinning spinneret, extruding the spinning liquid obtained in the step P2 into the tubular hollow fiber spinning spinneret, extruding the spinning liquid and the core liquid at the spinning speed of 20-40m/min, performing composite molding, and then placing the obtained product in water at 15-25 ℃ for solidification molding;

and P4, washing and drying the solidified long fiber, and shearing to a set length to obtain the composite water-resistant fiber.

Further, the preparation method of the high-water-resistance food packaging base paper comprises the following steps:

s1, preparing surface sizing agent: sequentially adding the liquid paraffin and stearic acid into a reaction kettle, stirring at 80-100 ℃ for reaction for 15-30 min, adding the layered silicate, dissolving the polysaccharide compound into 100-200 parts by weight of water to prepare an aqueous solution, preheating the aqueous solution to 80-90 ℃, dripping the aqueous solution into the reaction kettle for 20-30 min, adding the sodium borate after dripping, and stirring at 60-90 ℃ for reaction for 10-20 min; adding the rest materials of the flour slurry layer, and uniformly stirring to obtain flour slurry layer slurry;

s2, preparing a bottom slurry layer slurry: mixing the wood pulp and the bamboo pulp to obtain mixed pulp, adding the wet strength agent and the antibacterial agent, and uniformly stirring to obtain bottom pulp layer pulp;

s3, molding: respectively flowing out the slurry of the surface slurry layer and the bottom slurry layer by utilizing a multi-layer slurry box, and forming on a net;

s4, compounding a surface slurry layer and a bottom slurry layer: and compounding the wet paper web of the surface pulp layer and the bottom pulp layer, squeezing and dehydrating the paper by using a vacuum squeezing roller, drying at 100-110 ℃, and coiling to form paper to obtain the food packaging base paper.

The high-water-resistance food packaging body paper has the advantages of good water resistance, simplicity in preparation, environment friendliness, health and environment friendliness.

Detailed Description

In order that the above-recited objects, features and advantages of the present application will become more readily apparent, a more particular description of embodiments of the application will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings.

The high-water-resistance food packaging base paper comprises a surface pulp layer and a bottom pulp layer, wherein the surface pulp layer comprises the following raw materials in parts by weight:

Preferably, the wood pulp used for the surface pulp layer is softwood pulp and/or hardwood pulp, the mass percentage concentration of the wood pulp is 3-5%, and the beating degree is 30-38 DEG SR.

More preferably, the wood pulp used for the top layer is a mixture of softwood pulp and hardwood pulp, wherein the absolute dry mass ratio of the softwood pulp to the hardwood pulp is (1-3): 1, the softwood pulp is long fiber wood pulp, wherein the fiber length is 3-5 mm; the hardwood pulp is short fiber wood pulp, and the fiber length is 0.5-0.8 mm.

Preferably, the mass percentage concentration of the tough leather pulp is 3-6%, and the beating degree is 35-40 DEG SR.

As some embodiments of the present application, the hydrophobic modifier may be one or more of butyl acrylate, methyl methacrylate, hexamethyldisilazane, or dodecyl trimethoxysilane.

Preferably, the wet strength agent is polyamide epichlorohydrin.

Preferably, the dispersant is one or more of SN-50405, polyethylene oxide (PEO), or Polyacrylamide (PAM).

Preferably, the defoamer is silicone oil 200cs or SN-13302.

Preferably, the polysaccharide compound is one or more of starch, pectin or carrageenan.

As some embodiments of the application, the layered silicate is one or more of bentonite, kaolin, montmorillonite, or talc.

preferably, the wood pulp used for the bottom pulp layer is softwood pulp and/or hardwood pulp, the mass percentage concentration of the wood pulp is 6-10%, and the beating degree is 32-40 DEG SR.

More preferably, the wood pulp used for the bottom pulp layer is a mixture of softwood pulp and hardwood pulp, wherein the absolute dry mass ratio of the softwood pulp to the hardwood pulp is (2-5): 1, the softwood pulp is long fiber wood pulp, wherein the fiber length is 3-5 mm; the hardwood pulp is short fiber wood pulp, and the fiber length is 0.5-0.8 mm.

Preferably, the mass percentage concentration of the bamboo pulp is 5-10%, and the beating degree is 30-35 DEG SR.

Preferably, the wet strength agent is acrylamide grafted copolymer starch, and the use of the wet strength agent can increase the adsorptivity of the internal fibers of the paper, and simultaneously form electrostatic interaction with the internal fibers of the paper, so that the strength of the paper is improved.

Preferably, the antibacterial agent is one or more of quaternary ammonium salt antibacterial agent, biguanide antibacterial agent, alcohol antibacterial agent, phenolic antibacterial agent or pyridine antibacterial agent.

More preferably, the antibacterial agent further comprises 20 to 30% of inorganic acid salt of cationic higher fatty amine based on the total weight thereof.

Preferably, the length of the main fiber is 2-10 mm; the length of the branch fiber is 0.1-3 mm.

Preferably, the diameter of the main fiber is 0.2-0.5 mm; the diameter of the branch fiber is 0.1-0.3 mm.

Preferably, the branch fibers may be one or more of brucite fibers, asbestos fibers, carbon fibers or artificial chopped fibers, such as polyvinyl alcohol fibers, polyether ether ketone fibers, aramid fibers and the like.

p1, firstly, respectively adding 10 to 20 weight parts of polyvinylidene fluoride, 50 to 80 weight parts of solvent and 3 to 5 weight parts of additive into a stirring kettle, and stirring for 10 to 20 minutes at the temperature of between 60 and 80 ℃ for later use;

p2, adding 13-25% of branch fibers by volume percent into the mixed solution obtained in the step P1, fully and uniformly stirring, and standing for 24-48 h for defoaming to obtain spinning solution;

and P4, after spinning, washing and drying the solidified long fiber, and shearing to a set length to obtain the composite water-resistant fiber.

Further, in the step P1, the solvent is one of N-methylpyrrolidone, dimethylformamide, dimethylacetamide and dimethylsulfoxide; the additive is one or more of polyethylene glycol, sodium dodecyl sulfate or sodium dodecyl sulfate.

In addition, the application also provides a preparation method of the high-water-resistance food packaging paper, which comprises the following steps:

In the high-water-resistance food packaging body paper, a surface pulp layer and a bottom pulp layer are respectively arranged to form a double-layer main body structure of the food packaging body paper: firstly, a high-toughness and high-strength base stock layer is formed to endow the food packaging base paper with good tensile strength and burst index, so that the whole base paper is tough and is not easy to crack; meanwhile, the surface pulp layer with high water resistance is arranged on the bottom pulp layer to endow the food packaging base paper with good water resistance, so that the obtained food packaging base paper has high strength and good water resistance.

Specifically, in the preparation process of the composite water-resistant fiber, the prefabricated branch fiber with a shorter length is added into the spinning solution, and the branch fiber is embedded into the main fiber through the spinning process, in the composite water-resistant fiber, because the size limitation of the branch fiber and the main fiber are not completely the same as the orientation of the branch fiber and the main fiber, when the composite water-resistant fiber is added into the surface size layer, most of the main fiber can be arranged in the surface size layer in a direction parallel to the paper surface under the action of gravity, and at the moment, part of the branch fiber embedded into the main fiber can be exposed on the outer surface of the composite water-resistant fiber and then exposed on the surface of the surface size layer; on the basis, by virtue of the actions of liquid paraffin, polysaccharide compound, stearic acid, phyllosilicate and sodium borate, the branch fibers can form waxy projections on the surface of the surface sizing layer, and the water resistance of the surface sizing layer is greatly improved by utilizing the hydrophobic and hydrophobic actions of the waxy projections.

The high water resistance food packaging base paper and the preparation method thereof are illustrated by the following specific examples:

example 1

The preparation of the composite water-resistant fiber comprises the following steps: firstly, respectively adding 12 parts by weight of polyvinylidene fluoride, 60 parts by weight of solvent and 4 parts by weight of additive into a stirring kettle, and stirring for 15min at 70 ℃ for later use; adding 20% by volume of branch fibers into the mixed solution obtained in the step P1, fully and uniformly stirring, standing for 48 hours, and defoaming to obtain spinning solution; taking purified water as core liquid, filling the core liquid into a central tube of a tubular hollow fiber spinning jet, extruding the obtained spinning liquid into the tubular hollow fiber spinning jet, extruding the spinning liquid and the core liquid at the spinning speed of 30m/min, performing composite molding, and then placing the obtained spinning liquid and the core liquid into water at 15 ℃ for solidification molding; and after spinning, washing the solidified long fiber with water, drying, and shearing to 3-5 mm to obtain the composite water-resistant fiber.

Example 2

Preparation of high-water-resistance food packaging base paper:

wherein the surface slurry layer comprises the following raw materials in parts by weight:

the bottom slurry layer comprises the following raw materials in parts by weight:

the preparation process of the high water-resistant food packaging base paper comprises the following steps:

s1, preparing surface sizing agent: sequentially adding the liquid paraffin and stearic acid into a reaction kettle, stirring at 80 ℃ for reaction for 30min, adding the layered silicate, dissolving the polysaccharide compound in 100 parts by weight of water to prepare an aqueous solution, preheating the aqueous solution to 80 ℃, dropwise adding the aqueous solution into the reaction kettle for 20min, adding the sodium borate after the dropwise adding is completed, and stirring at 60 ℃ for reaction for 20min; adding the rest materials of the flour slurry layer, and uniformly stirring to obtain flour slurry layer slurry;

s4, compounding a surface slurry layer and a bottom slurry layer: and compounding the wet paper web of the surface pulp layer and the bottom pulp layer, squeezing and dehydrating the paper by using a vacuum squeezing roller, drying at 100 ℃, and coiling to form paper to obtain the food packaging base paper.

Example 3

Preparation of high-water-resistance food packaging base paper:

s1, preparing surface sizing agent: sequentially adding the liquid paraffin and stearic acid into a reaction kettle, stirring at 92 ℃ for reaction for 20min, adding the layered silicate, dissolving the polysaccharide compound in 160 parts by weight of water to prepare an aqueous solution, preheating the aqueous solution to 90 ℃, dropwise adding the aqueous solution into the reaction kettle for 20min, adding the sodium borate after the dropwise adding is completed, and stirring at 80 ℃ for reaction for 15min; adding the rest materials of the flour slurry layer, and uniformly stirring to obtain flour slurry layer slurry;

s4, compounding a surface slurry layer and a bottom slurry layer: and compounding the wet paper web of the surface pulp layer and the bottom pulp layer, squeezing and dehydrating the paper by using a vacuum squeezing roller, drying at 105 ℃, and coiling to form paper to obtain the food packaging base paper.

Example 4

Preparation of high-water-resistance food packaging base paper:

s1, preparing surface sizing agent: sequentially adding the liquid paraffin and stearic acid into a reaction kettle, stirring at 100 ℃ for reaction for 15min, adding the layered silicate, dissolving the polysaccharide compound in 200 parts by weight of water to prepare an aqueous solution, preheating the aqueous solution to 90 ℃, dropwise adding the aqueous solution into the reaction kettle for 20min, adding the sodium borate after the dropwise adding is completed, and stirring at 90 ℃ for reaction for 10min; adding the rest materials of the flour slurry layer, and uniformly stirring to obtain flour slurry layer slurry;

s4, compounding a surface slurry layer and a bottom slurry layer: and compounding the wet paper web of the surface pulp layer and the bottom pulp layer, squeezing and dehydrating the paper by using a vacuum squeezing roller, drying at 108 ℃, and coiling to form paper to obtain the food packaging base paper.

Comparative example 1

Preparation of high-water-resistance food packaging base paper:

the only difference between comparative example 1 and example 3 above is that: the composite water-resistant fiber is not added in the face slurry layer, and the rest is the same, and is not described in detail herein.

Comparative example 2

Preparation of high-water-resistance food packaging base paper:

the only difference between comparative example 2 and example 3 described above is that: liquid paraffin and stearic acid are not added into the surface sizing agent layer, when the surface sizing agent layer sizing agent is prepared, the layered silicate and the water solution of the polysaccharide compound preheated to 90 ℃ are directly mixed, then sodium borate is added, and stirring reaction is carried out for 15min at 80 ℃; and adding the rest materials of the surface slurry layer, and uniformly stirring to obtain the surface slurry layer slurry, wherein the rest materials are the same and are not described in detail.

Comparative example 3

Preparation of high-water-resistance food packaging base paper:

the only difference between comparative example 3 and example 3 described above is that: when the slurry of the surface sizing layer is prepared, directly adding an aqueous solution of a polysaccharide compound preheated to 90 ℃ for mixing after the reaction of liquid paraffin and stearic acid is completed, adding sodium borate, and stirring for reaction for 15min at 80 ℃; and adding the rest materials of the surface slurry layer, and uniformly stirring to obtain the surface slurry layer slurry, wherein the rest materials are the same and are not described in detail.

Comparative example 4

Preparation of high-water-resistance food packaging base paper:

the only difference between comparative example 3 and example 3 described above is that: the polysaccharide compound is not added into the surface sizing agent layer, when the surface sizing agent layer sizing agent is prepared, the layered silicate is added, then the sodium borate is directly added, and the stirring reaction is carried out for 15min at 80 ℃; adding the rest materials of the flour slurry layer, and uniformly stirring to obtain flour slurry layer slurry; the remainder is the same and will not be described in detail herein.

Comparative example 5

Preparation of high-water-resistance food packaging base paper:

the only difference between comparative example 3 and example 3 described above is that: sodium borate is not added into the surface sizing agent layer, when the surface sizing agent layer sizing agent is prepared, after the water solution of the polysaccharide compound is added dropwise, the rest materials of the surface sizing agent layer are directly added, and the surface sizing agent layer sizing agent is obtained after uniform stirring; the remainder is the same and will not be described in detail herein. .

Test example 1

The water resistance of the side of the face stock layer of the base paper for food packaging prepared in examples 2 to 4 and comparative examples 1 to 5 was measured by using a Cobb water absorption tester according to GB/T1540 method for measuring water absorption of paper and paperboard (Wobbe method), and the results are shown in Table 1 below:

TABLE 1 results of Water resistance test of base paper for food packaging

Although the present application is disclosed above, the present application is not limited thereto. In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "exemplary embodiments," "examples," "particular examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the application, and the scope of the application should be assessed accordingly to that of the appended claims.

Claims

1. The high-water-resistance food packaging base paper is characterized by comprising a surface pulp layer and a bottom pulp layer, wherein the surface pulp layer comprises the following raw materials in parts by weight:

40-60 parts of wood pulp;

20-30 parts of tough leather paste;

3-8 parts of composite water-resistant fiber;

3-5 parts of a wet strength agent;

1-3 parts of a dispersing agent;

0.5-2 parts of a hydrophobic modifier;

0.2-0.5 part of defoaming agent;

2-5 parts of liquid paraffin;

0.01-0.02 parts of polysaccharide compound;

0.5-1 parts of stearic acid;

0.5-2 parts of layered silicate;

0.5-1 part of sodium borate;

60-80 parts of wood pulp;

15-25 parts of bamboo pulp;

8-10 parts of a wet strength agent;

0.5-1.5 parts of an antibacterial agent;

wherein the hydrophobic modifier is one or more of butyl acrylate, methyl methacrylate, hexamethyldisilazane or dodecyl trimethoxy silane;

the preparation method of the composite water-resistant fiber comprises the following steps of:

p1, adding 10-20 parts by weight of polyvinylidene fluoride, 50-80 parts by weight of solvent and 3-5 parts by weight of additive into a stirring kettle respectively, and stirring at 60-80 ℃ for 10-20 minutes for later use;

p2, adding 13-25% of branch fibers by volume into the mixed solution obtained in the step P1, fully and uniformly stirring, and standing for 24-48 h for defoaming to obtain a spinning solution;

p3, adopting purified water as core liquid, filling the core liquid into a central tube of a tubular hollow fiber spinning spinneret, extruding the spinning liquid obtained in the step P2 into the tubular hollow fiber spinning spinneret, extruding the spinning liquid and the core liquid at the same time at a spinning speed of 20-40m/min, performing composite molding, and then placing the obtained product in water at 15-25 ℃ for solidification molding;

2. The high water resistant food packaging base paper according to claim 1, wherein the thickness ratio of the base stock layer to the top stock layer is (3-10): 1.

3. The high water resistant food packaging base paper according to claim 1, wherein the wet strength agent is acrylamide graft copolymerized starch.

4. The high water resistance food packaging base paper according to claim 1, wherein the antibacterial agent is one or more of quaternary ammonium salt antibacterial agent, biguanide antibacterial agent, alcohol antibacterial agent, phenolic antibacterial agent or pyridine antibacterial agent.

5. The high water resistance food packaging base paper according to claim 1, wherein the length of the main fiber is 2-10 mm; the length of the branch fiber is 0.1-3 mm; the diameter of the main fiber is 0.2-0.5 mm; the diameter of the branch fiber is 0.1-0.3 mm.

6. The high water resistance food wrap base paper according to claim 1 or 5, wherein the branch fibers are one or more of artificial chopped fibers, carbon fibers, asbestos fibers or brucite fibers.

7. The high water resistant food packaging base paper according to claim 1, wherein the preparation method of the high water resistant food packaging base paper comprises the following steps: