Waterproof and stain-resistant corrugated paperboard and method for manufacturing the same

Abstract

The present application relates to a kind of waterproof and pollution-resistant corrugated paperboard and its preparation method, belong to corrugated paperboard technical field, the corrugated paperboard is sequentially composed of outer board paper layer, corrugated core paper layer and bottom board paper layer from top to bottom, adjacent layer is bonded by adhesive;The outer board paper layer and bottom board paper layer are the same in raw material;The outer board paper layer and bottom board paper layer include the following raw materials: red pine pulp, waste paper pulp, 2-methyl-2-octadecyl acrylate, N-hydroxymethyl acrylamide, 3-aminopropyl triethoxysilane, four acicular zinc oxide whisker, white vine extract, glabrous kanzonol.The corrugated paperboard product prepared by the present application has water resistance and antibacterial property, and due to the antibacterial property, bacteria are difficult to stay on the corrugated paperboard and accumulate dust and other pollutants, and the water resistance effectively prevents contaminated liquids from adhering to the surface of the paper, which improves the pollution resistance of the corrugated paperboard.

Description

Technical Field

[0001] This invention belongs to the field of corrugated cardboard technology, specifically relating to a waterproof and stain-resistant corrugated cardboard and its preparation method. Background Technology

[0002] Corrugated cardboard is a multi-layered laminate, consisting of at least one corrugated core layer and one cardboard layer. It is commonly used for packaging, transporting, and storing goods. Therefore, corrugated cardboard needs to have good water and stain resistance to protect packaged or stored goods from damage in humid or polluted environments, thus ensuring product performance. While some existing corrugated cardboard on the market already possesses water and stain resistance, their overall performance is relatively poor. Therefore, there is an urgent need for a corrugated cardboard with superior water and stain resistance. Summary of the Invention

[0003] The purpose of this invention is to provide a waterproof and stain-resistant corrugated cardboard and its preparation method, which solves the problem of poor waterproof and stain-resistant performance of existing corrugated cardboard.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A waterproof and stain-resistant corrugated cardboard, wherein the corrugated cardboard is composed of an outer cardboard layer, a corrugated core cardboard layer and a bottom cardboard layer from top to bottom, and adjacent layers are bonded together with adhesive;

[0006] The outer paper layer and the bottom paper layer are made of the same raw materials;

[0007] The outer paper layer and the bottom paper layer comprise the following parts by weight of raw materials:

[0008] 60-80 parts by weight of red pine pulp, 50-60 parts by weight of waste paper pulp, 4-5.5 parts by weight of octadecyl 2-methyl-2-acrylate, 2.3-3.2 parts by weight of N-hydroxymethylacrylamide, 0.2-0.3 parts by weight of 3-aminopropyltriethoxysilane, 5.5-6 parts by weight of tetraneedle-shaped zinc oxide whiskers, 3.5-5.5 parts by weight of lecithin, and 3-4.5 parts by weight of glycyrrhizin.

[0009] As a preferred embodiment of the present invention, the raw materials for the outer paper layer and the bottom paper layer further include anhydrous ethanol and cationic polyacrylamide;

[0010] Cationic polyacrylamide can effectively increase the retention rate of fine fibers in red pine pulp and waste paper pulp in paper, while also enabling tetraneedle-shaped zinc oxide whiskers, galangin and glycyrrhizin to be evenly dispersed in the pulp.

[0011] As a preferred embodiment of the present invention, the cationic polyacrylamide is 0.3-0.4 parts by weight.

[0012] As a preferred embodiment of the present invention, the anhydrous ethanol is 120-140 parts by weight.

[0013] As a preferred embodiment of the present invention, the preparation method of the outer paper layer and the bottom paper layer specifically includes the following steps:

[0014] S1. Filter and screen the red pine pulp and waste paper pulp to remove impurities, and beat them in a grinding pan to obtain pulp for later use;

[0015] S2. Mix N-hydroxymethylacrylamide, octadecyl 2-methyl-2-acrylate, 3-aminopropyltriethoxysilane and anhydrous ethanol and stir in a water bath under controlled temperature. After stirring, add slurry, tetraneedle-shaped zinc oxide whiskers, scutellarin, glycyrrhizin and cationic polyacrylamide, stir at controlled speed, and then oscillate under controlled temperature to obtain a mixture.

[0016] S3. The mixture is shaped, dehydrated, and then pressed and dehydrated again. Then it is dried, rolled, rewound, and slit to obtain the finished outer paper layer and the bottom paper layer.

[0017] As a preferred technical solution of the present invention, the pulping in step S1 is pulping to 30-35°SR.

[0018] As a preferred embodiment of the present invention, the temperature of the temperature-controlled water bath stirring in step S2 is 45-50℃ and the time is 5-8 min; the speed of the speed-controlled stirring is 750-800 rpm and the time is 4-6 h; the temperature of the temperature-controlled constant temperature oscillation is 45-50℃ and the time is 20-30 min.

[0019] As a preferred embodiment of the present invention, the forming dehydration in step S3 is dehydration to a dryness of 15-20%; the pressing dehydration is dehydration to a dryness of 45-50%.

[0020] A method for preparing waterproof and stain-resistant corrugated cardboard, the method specifically including the following steps:

[0021] The corrugated core paper layer is placed in a corrugated mold to make corrugated paper. Adhesive is applied to both sides of the corrugated paper. The outer linerboard layer is glued to one side of the corrugated core paper layer, and the bottom linerboard layer is glued to the other side of the corrugated core paper layer. The paper is then dried at a controlled temperature to produce a waterproof and stain-resistant corrugated cardboard product.

[0022] As a preferred embodiment of the present invention, the temperature of the temperature-controlled drying is 110-130℃.

[0023] As a preferred embodiment of the present invention, the corrugated core paper layer is the core paper layer obtained by our company's patent number CN115198568B; the adhesive is a water-based adhesive, model G-305, purchased from Foshan Dezhong Chemical Technology Co., Ltd.

[0024] The beneficial effects of this invention are:

[0025] (1) In this invention, octadecyl 2-methyl-2-acrylate and N-hydroxymethylacrylamide, which have hydrophobic structures, are used as functional monomers and react with each other to form a network structure, which improves the density of the pulp and increases the hydrophobicity of the paperboard, making it difficult for water molecules to penetrate into the paperboard. At the same time, 3-aminopropyltriethoxysilane is used to improve the interfacial compatibility between the pulp surface and the functional monomers, thereby giving the corrugated paperboard excellent waterproof performance.

[0026] (2) The tetraneedle-shaped zinc oxide whiskers selected in this invention have needle-like tips. When added to the system, some of the needle-like tips of the whiskers will embed into the fiber wall of the pulp. When the cardboard comes into contact with bacteria, zinc ions can interfere with the activity of enzymes in the bacteria, inhibiting the growth and reproduction of bacteria. The selected scutellarin can destroy the integrity of the bacterial cell membrane, leading to an imbalance between the intracellular and extracellular matrix. The selected glycyrrhizin can affect the synthesis of bacterial DNA, RNA and protein, reducing the metabolic rate of bacteria. The three complement each other and can effectively cause the death of foreign bacteria and reduce bacterial invasion in multiple dimensions, so that the corrugated cardboard has outstanding antibacterial properties.

[0027] (3) The corrugated cardboard prepared by the present invention has both waterproof and antibacterial properties. Due to this antibacterial property, bacteria have difficulty staying on the corrugated cardboard and accumulating dust and other pollutants. The waterproof property effectively prevents polluting liquids from wetting and adhering to the paper surface. Both of these properties together improve the pollution resistance of the corrugated cardboard. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] A waterproof and stain-resistant corrugated cardboard, wherein the corrugated cardboard is composed of an outer cardboard layer, a corrugated core cardboard layer and a bottom cardboard layer from top to bottom, and adjacent layers are bonded together with adhesive;

[0031] The outer paper layer and the bottom paper layer are made of the same raw materials;

[0032] The outer paper layer and the bottom paper layer comprise the following parts by weight of raw materials:

[0033] 80 parts by weight of red pine pulp, 50 parts by weight of waste paper pulp, 4 parts by weight of octadecyl 2-methyl-2-acrylate, 2.8 parts by weight of N-hydroxymethylacrylamide, 0.3 parts by weight of 3-aminopropyltriethoxysilane, 5.5 parts by weight of tetraneedle-shaped zinc oxide whiskers, 3.5 parts by weight of scutellarin, 4.5 parts by weight of glycyrrhizin, 120 parts by weight of anhydrous ethanol, and 0.35 parts by weight of cationic polyacrylamide.

[0034] The preparation method of the outer paper layer and the bottom paper layer specifically includes the following steps:

[0035] S1. Filter and screen the red pine pulp and waste paper pulp in the above weight proportions to remove impurities, and beat them in a grinding disc to 30°SR to obtain pulp for later use;

[0036] S2. Mix N-hydroxymethylacrylamide, octadecyl 2-methyl-2-acrylate, 3-aminopropyltriethoxysilane and anhydrous ethanol and stir in a water bath at 45°C for 8 minutes. After stirring, add slurry, tetraneedle-shaped zinc oxide whiskers, scutellarin, glycyrrhizin and cationic polyacrylamide, and stir at 750 rpm for 5 hours. After stirring, keep the temperature at 45°C and shake for 20 minutes to obtain the mixture.

[0037] S3. The mixture is shaped and dehydrated to a dryness of 20%, then pressed and dehydrated to a dryness of 45%. After drying, rolling, rewinding and slitting, the outer paper layer and the bottom paper layer are obtained.

[0038] A method for preparing waterproof and stain-resistant corrugated cardboard, the method specifically including the following steps:

[0039] Place the corrugated core paper layer into a corrugated mold to make corrugated paper. Apply adhesive to both sides of the corrugated paper. Attach the outer linerboard layer to one side of the corrugated core paper layer and the bottom linerboard layer to the other side of the corrugated core paper layer. Dry at a controlled temperature of 110℃ to obtain a waterproof and stain-resistant corrugated cardboard product.

[0040] The preparation method of the corrugated core paper layer is the same as the preparation method of the core paper layer described in patent number CN115198568B of our company (i.e., Zhengye Packaging (Zhongshan) Co., Ltd.); the adhesive is a water-based adhesive, model G-305, purchased from Foshan Dezhong Chemical Technology Co., Ltd.

[0041] Example 2

[0042] A waterproof and stain-resistant corrugated cardboard, wherein the corrugated cardboard is composed of an outer cardboard layer, a corrugated core cardboard layer and a bottom cardboard layer from top to bottom, and adjacent layers are bonded together with adhesive;

[0043] The outer paper layer and the bottom paper layer are made of the same raw materials;

[0044] The outer paper layer and the bottom paper layer comprise the following parts by weight of raw materials:

[0045] 60 parts by weight of red pine pulp, 55 parts by weight of waste paper pulp, 4.7 parts by weight of octadecyl 2-methyl-2-acrylate, 2.3 parts by weight of N-hydroxymethylacrylamide, 0.2 parts by weight of 3-aminopropyltriethoxysilane, 6 parts by weight of tetraneedle-shaped zinc oxide whiskers, 4.5 parts by weight of scutellarin, 3.8 parts by weight of glycyrrhizin, 140 parts by weight of anhydrous ethanol, and 0.3 parts by weight of cationic polyacrylamide.

[0046] The preparation method of the outer paper layer and the bottom paper layer specifically includes the following steps:

[0047] S1. Filter and screen the red pine pulp and waste paper pulp in the above weight proportions to remove impurities, and beat them in a grinding disc to 30°SR to obtain pulp for later use;

[0048] S2. Mix N-hydroxymethylacrylamide, octadecyl 2-methyl-2-acrylate, 3-aminopropyltriethoxysilane and anhydrous ethanol and stir in a water bath at 48°C for 5 minutes. After stirring, add slurry, tetraneedle-shaped zinc oxide whiskers, scutellarin, glycyrrhizin and cationic polyacrylamide, and stir at 800 rpm for 4 hours. After stirring, keep the temperature at 50°C and shake for 25 minutes to obtain the mixture.

[0049] S3. The mixture is shaped and dehydrated to a dryness of 15%, then pressed and dehydrated to a dryness of 50%. After drying, rolling, rewinding and slitting, the outer paper layer and the bottom paper layer are obtained.

[0050] A method for preparing waterproof and stain-resistant corrugated cardboard, the method specifically including the following steps:

[0051] Place the corrugated core paper layer into a corrugated mold to make corrugated paper. Apply adhesive to both sides of the corrugated paper. Attach the outer linerboard layer to one side of the corrugated core paper layer and the bottom linerboard layer to the other side of the corrugated core paper layer. Dry at a controlled temperature of 120℃ to obtain a waterproof and stain-resistant corrugated cardboard product.

[0052] The preparation method of the corrugated core paper layer is the same as the preparation method of the core paper layer described in patent number CN115198568B of our company (i.e., Zhengye Packaging (Zhongshan) Co., Ltd.); the adhesive is a water-based adhesive, model G-305, purchased from Foshan Dezhong Chemical Technology Co., Ltd.

[0053] Example 3

[0054] A waterproof and stain-resistant corrugated cardboard, wherein the corrugated cardboard is composed of an outer cardboard layer, a corrugated core cardboard layer and a bottom cardboard layer from top to bottom, and adjacent layers are bonded together with adhesive;

[0055] The outer paper layer and the bottom paper layer are made of the same raw materials;

[0056] The outer paper layer and the bottom paper layer comprise the following parts by weight of raw materials:

[0057] 70 parts by weight of red pine pulp, 60 parts by weight of waste paper pulp, 5.5 parts by weight of octadecyl 2-methyl-2-acrylate, 3.2 parts by weight of N-hydroxymethylacrylamide, 0.25 parts by weight of 3-aminopropyltriethoxysilane, 5.7 parts by weight of tetraneedle-shaped zinc oxide whiskers, 5.5 parts by weight of scutellarin, 3.8 parts by weight of glycyrrhizin, 130 parts by weight of anhydrous ethanol, and 0.4 parts by weight of cationic polyacrylamide.

[0058] The preparation method of the outer paper layer and the bottom paper layer specifically includes the following steps:

[0059] S1. Filter and screen the red pine pulp and waste paper pulp in the above weight proportions to remove impurities, and beat them in a grinding disc to 35°SR to obtain pulp for later use;

[0060] S2. Mix N-hydroxymethylacrylamide, octadecyl 2-methyl-2-acrylate, 3-aminopropyltriethoxysilane and anhydrous ethanol and stir in a water bath at 50°C for 7 minutes. After stirring, add slurry, tetraneedle-shaped zinc oxide whiskers, scutellarin, glycyrrhizin and cationic polyacrylamide, and stir at 775 rpm for 6 hours. After stirring, keep the temperature at 48°C and shake for 30 minutes to obtain the mixture.

[0061] S3. The mixture is shaped and dehydrated to a dryness of 20%, then pressed and dehydrated to a dryness of 45%. After drying, rolling, rewinding and slitting, the outer paper layer and the bottom paper layer are obtained.

[0062] A method for preparing waterproof and stain-resistant corrugated cardboard, the method specifically including the following steps:

[0063] Place the corrugated core paper layer into a corrugated mold to make corrugated paper. Apply adhesive to both sides of the corrugated paper. Attach the outer linerboard layer to one side of the corrugated core paper layer and the bottom linerboard layer to the other side of the corrugated core paper layer. Dry at a controlled temperature of 130℃ to obtain a waterproof and stain-resistant corrugated cardboard product.

[0064] The preparation method of the corrugated core paper layer is the same as the preparation method of the core paper layer described in patent number CN115198568B of our company (i.e., Zhengye Packaging (Zhongshan) Co., Ltd.); the adhesive is a water-based adhesive, model G-305, purchased from Foshan Dezhong Chemical Technology Co., Ltd.

[0065] Comparative Example 1

[0066] Compared with Example 3, the difference is that octadecyl 2-methyl-2-acrylate was not added in Comparative Example 1, while the other operation steps and parameters remained unchanged.

[0067] Comparative Example 2

[0068] Compared with Example 3, the difference is that N-hydroxymethylacrylamide was not added in Comparative Example 2, while the other operation steps and parameters remained unchanged.

[0069] Comparative Example 3

[0070] Compared with Example 3, the difference is that 3-aminopropyltriethoxysilane was not added in Comparative Example 3, while the other operation steps and parameters remained unchanged.

[0071] Comparative Example 4

[0072] Compared with Example 3, the difference is that in Comparative Example 4, the four needle-shaped zinc oxide whiskers are 0 parts by weight, the scutellarin is 8.35 parts by weight, and the glycyrrhizin is 6.65 parts by weight, while the other operating steps and parameters remain unchanged.

[0073] Comparative Example 5

[0074] Compared with Example 3, the difference is that in Comparative Example 5, the four needle-shaped zinc oxide whiskers are 8.45 parts by weight, the scutellarin is 0 parts by weight, and the glycyrrhizin is 6.55 parts by weight, while the other operating steps and parameters remain unchanged.

[0075] Comparative Example 6

[0076] Compared with Example 3, the difference is that in Comparative Example 6, the tetraneedle-shaped zinc oxide whiskers are 7.6 parts by weight, the scutellarin is 7.4 parts by weight, and the glycyrrhizin is 0 parts by weight, while the other operating steps and parameters remain unchanged.

[0077] Test case

[0078] (1) Water absorption test: According to GB / T 461.3-2005, the corrugated cardboard products prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to water absorption test to provide feedback on their waterproof performance. The results are shown in Table 1.

[0079] (2) Antibacterial performance test: The antibacterial performance of the samples was qualitatively tested using the inhibition zone method with Escherichia coli and Staphylococcus aureus as test bacteria. Specifically, the corrugated cardboard products prepared in Examples 1-3 and Comparative Examples 4-6 were cut into 12 mm diameter discs as samples. The suspensions of Escherichia coli and Staphylococcus aureus were inoculated into nutrient agar medium and spread evenly. The cut samples were then placed in the center of the nutrient agar medium and placed in a constant temperature incubator. After incubation at 37°C for 24 h, the diameter of the inhibition zone of each sample was measured. The results are shown in Table 1.

[0080] (3) Stain resistance test: The corrugated cardboard products prepared in Examples 1-3 and Comparative Examples 1-6 were cut into squares with a side length of 50cm as samples. Dust was sprinkled on one side of the sample and left to stand for 1 hour. Then, it was rinsed with a small amount of tap water. The ease with which the dust on the sample surface was washed off was observed by eye. The sample surface was touched by hand to see if it felt sticky. The more difficult it was to wash off the dust and the sticky feeling on the sample surface, the less resistant the sample was to staining. Wastewater was splashed on the other side of the sample surface. After splashing wastewater 5 times, the area of ​​wastewater adhering to the sample surface was observed. The larger the area of ​​adhering area, the less resistant the sample was to staining. The results are shown in Table 2.

[0081] Table 1

[0082]

[0083]

[0084] As can be seen from Table 1, the corrugated cardboard product obtained by the present invention has excellent waterproof and antibacterial properties.

[0085] Table 2

[0086]

[0087] As can be seen from Table 2, the corrugated cardboard product obtained by the present invention has excellent stain resistance.

[0088] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0089] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A waterproof and stain-resistant corrugated cardboard, characterized in that, The corrugated cardboard is composed of an outer paper layer, a corrugated core paper layer and a bottom paper layer from top to bottom, and adjacent layers are bonded together with adhesive. The outer paper layer and the bottom paper layer are made of the same raw materials; The outer paper layer and the bottom paper layer comprise the following parts by weight of raw materials: 60-80 parts by weight of red pine pulp, 50-60 parts by weight of waste paper pulp, 4-5.5 parts by weight of octadecyl 2-methyl-2-acrylate, 2.3-3.2 parts by weight of N-hydroxymethylacrylamide, 0.2-0.3 parts by weight of 3-aminopropyltriethoxysilane, 5.5-6 parts by weight of tetraneedle-shaped zinc oxide whiskers, 3.5-5.5 parts by weight of scutellarin, and 3-4.5 parts by weight of glycyrrhizin. The preparation method of the outer paper layer and the bottom paper layer specifically includes the following steps: S1. Filter and screen the red pine pulp and waste paper pulp to remove impurities, and beat them in a grinding pan to obtain pulp for later use; S2. N-hydroxymethylacrylamide, octadecyl 2-methyl-2-acrylate, 3-aminopropyltriethoxysilane, and anhydrous ethanol are mixed and stirred in a temperature-controlled water bath. After stirring, the slurry, tetraneedle-shaped zinc oxide whiskers, scutellarin, glycyrrhizin, and cationic polyacrylamide are added. The mixture is stirred at a controlled speed, and then oscillated at a controlled temperature to obtain a mixture. The temperature of the temperature-controlled water bath stirring is 45-50℃ for 5-8 minutes; the speed of the controlled stirring is 750-800 rpm for 4-6 hours; and the temperature of the controlled temperature oscillation is 45-50℃ for 20-30 minutes. S3. The mixture is shaped, dehydrated, and then pressed and dehydrated again. Then it is dried, rolled, rewound, and slit to obtain the finished outer paper layer and the bottom paper layer.

2. The waterproof and stain-resistant corrugated cardboard according to claim 1, characterized in that, The cationic polyacrylamide is present in an amount of 0.3-0.4 parts by weight.

3. The waterproof and stain-resistant corrugated cardboard according to claim 1, characterized in that, The anhydrous ethanol is 120-140 parts by weight.

4. The waterproof and stain-resistant corrugated cardboard according to claim 1, characterized in that, The pulping described in step S1 is pulping to 30-35°SR.

5. The waterproof and stain-resistant corrugated cardboard according to claim 1, characterized in that, The forming dehydration in step S3 is to dehydrate to a dryness of 15-20%; the pressing dehydration is to dehydrate to a dryness of 45-50%.

6. A method for preparing a waterproof and stain-resistant corrugated cardboard as described in any one of claims 1-5, characterized in that, The preparation method specifically includes the following steps: The corrugated core paper layer is placed in a corrugated mold to make corrugated paper. Adhesive is applied to both sides of the corrugated paper. The outer linerboard layer is glued to one side of the corrugated core paper layer, and the bottom linerboard layer is glued to the other side of the corrugated core paper layer. The paper is then dried at a controlled temperature to produce a waterproof and stain-resistant corrugated cardboard product.

7. The method for preparing waterproof and stain-resistant corrugated cardboard according to claim 6, characterized in that, The temperature for temperature-controlled drying is 110-130℃.

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