Preparation process and application of waterproof and antiskid paperboard

Abstract

The invention discloses a preparation process of a waterproof and antiskid paperboard. The preparation process comprises the following steps: premixing functional particles and waterproof wax according to a mass ratio of 4: 1; s2, grinding the mixture obtained in the step S1 in a three-roll grinder until the particle size is less than or equal to 15 microns to form a stable suspension; adding anti-skid resin and other auxiliaries into a dispersion tank according to a mass ratio for dispersion, and then adding the suspension obtained in the step S2 for continuous dispersion to obtain the water-based environment-friendly coating. A micro gravure coating machine is used, and paperboard coating is conducted on the water-based environment-friendly coating obtained in the step S3 under the setting of viscosity, wet coating weight and coating speed; the coated paperboard is dried for about 5 minutes in a natural environment, a composite functional layer with the thickness of 10-15 microns is formed, and finally the paperboard with the waterproof and anti-skid functions is obtained. By means of the mode, the waterproof and anti-skid paperboard overcomes the mutual exclusion relation between the waterproof performance and the anti-skid performance, and cooperation of the waterproof function and the anti-skid function of the surface of the paperboard is achieved.

Description

Technical Field

[0001] This invention relates to the field of paperboard development technology, and in particular to a preparation process and application of waterproof and non-slip paperboard. Background Technology

[0002] With the rapid development of the cold chain logistics industry, the market demand for refrigerated and frozen foods is constantly increasing. Currently, the packaging, protection, stacking, and transportation of refrigerated and frozen foods are usually done using two methods: cardboard boxes and plastic boxes. Compared with plastic boxes, cardboard boxes have lower production costs, better environmental performance, and are recyclable. However, cardboard boxes have some limitations in refrigerated and frozen environments, such as poor moisture absorption. Specifically, the low temperature and high humidity environment in cold storage will cause cardboard boxes to absorb moisture, leading to a decrease in their strength and making them prone to deformation or collapse. In addition, cardboard boxes also have poor barrier properties against water vapor and oxygen.

[0003] To address the aforementioned issues, further development of waterproof and anti-slip cardboard is needed. Those skilled in the art should know that packaging for refrigerated and frozen foods typically requires both waterproof and anti-slip properties. Waterproofing is primarily based on the need for packaging materials to prevent the penetration of condensation during storage and transportation of refrigerated foods, in order to keep the food dry and fresh. Anti-slip properties are primarily based on the need for packaging materials to have good anti-slip properties during cold storage and transportation, in order to ensure the safety of handling and storage.

[0004] Regarding the anti-slip performance of cardboard, some existing technologies use inorganic particles such as silica sand and talc powder with a particle size of 50-150µm as anti-slip particles, which are mixed into the cardboard surface with adhesives to enhance the anti-slip performance. While this method is feasible, the wide particle size distribution of the anti-slip particles leads to several problems. Firstly, the surface roughness fluctuates greatly, the particles are prone to detachment, and the anti-slip effect is poor. Secondly, the particles can damage the cardboard's density, hindering its waterproof performance. Furthermore, silica sand dust can diffuse in the production line, failing to meet the requirements of the ISO 14001 environmental management system. Regarding the waterproof performance of cardboard, some existing technologies use solvent-based varnish coatings, but the cured surface is smooth, with a dry COF < 0.4µm, which cannot meet the anti-slip requirements.

[0005] Based on the above research, existing technologies for waterproof and anti-slip cardboard present performance contradictions. Specifically, waterproof coatings require dense film formation, while anti-slip requires a rough surface, making the two incompatible. Furthermore, the large size of the anti-slip particles makes them prone to detachment, causing dust and other environmental pollution problems. In sloping transport scenarios, especially at angles greater than 30°, the wet anti-slip coefficient (COF) of existing cardboard is less than 0.5u, making cartons prone to sliding and falling, resulting in poor adaptability. Therefore, there is an urgent need to develop a new process for preparing waterproof and anti-slip cardboard to overcome the mutually exclusive relationship between waterproof and anti-slip properties, achieving synergistic dual-function on the cardboard surface, while simultaneously simplifying the production process and reducing energy consumption. Summary of the Invention

[0006] The main technical problem solved by this invention is to provide a manufacturing process and application of waterproof and anti-slip cardboard. By developing a water-based environmentally friendly coating formula and combining it with a micron-level resin particle directional embedding process, the anti-slip reliability under slope conditions is significantly improved. At the same time, the coating-curing process is completed in a single step, reducing energy consumption by 40%, which is especially suitable for packaging boxes of refrigerated and frozen products.

[0007] To solve the above-mentioned technical problems, one technical solution adopted by the present invention is to provide a manufacturing process for waterproof and non-slip cardboard, the manufacturing process comprising the following steps: S1. Premix the functional granules and waterproof wax at a mass ratio of 4:1; S2. Grind the mixture from S1 in a three-roll mill until the particle size is ≤15µm to form a stable suspension; S3. Add the anti-slip resin and other additives to the dispersion tank according to the mass ratio for dispersion, and then add the suspension obtained in S2 to continue dispersion to obtain a water-based environmentally friendly coating. S4. Using a micro-gravure coating machine, apply the water-based environmentally friendly coating obtained in S3 to the paperboard under the settings of viscosity, wet coating amount and coating speed; S5. The coated paperboard is naturally dried to form a composite functional layer with a thickness of 10~15um, ultimately obtaining paperboard with waterproof and anti-slip functions.

[0008] Preferably, the functional particles in S1 are a combination of type 1207 acrylic emulsion and type 1209 acrylic emulsion.

[0009] Preferably, the ratio of the 1207 type acrylic emulsion to the 1209 type acrylic emulsion is 2:1.

[0010] Preferably, in step S2, the grinding temperature in the three-roll mill needs to be controlled within a low temperature range of 50~60℃.

[0011] Preferably, the dispersion conditions of the anti-slip resin and other additives in the S3 dispersion tank are controlled at a rotation speed of 800 rpm and a dispersion time of 30 minutes, and the dispersion time continues for at least 15 minutes after the addition of the S2 suspension.

[0012] Preferably, the anti-slip resin in S3 is selected as a water-based epoxy resin with a solid content ≥45% and a particle size controlled at 10~15um.

[0013] Preferably, the other additives are defoamers and leveling agents.

[0014] Preferably, the viscosity of the water-based environmentally friendly coating in step S4 is controlled at 3500±500 cps, and the wet coating amount is 10 g / m³. 2The coating speed is controlled at 60m / min, and the coating is rolled at 60℃.

[0015] Preferably, the mass ratios of the functional particles, waterproof wax, anti-slip resin, and other additives are 60%, 15%, 20%, and 5%, respectively.

[0016] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is: to provide a process for preparing waterproof and non-slip cardboard and its application in the preparation of refrigerated and frozen product packaging boxes.

[0017] The beneficial effects of this invention are: This invention addresses two key issues. First, by designing a hydrophobic layer and combining it with micron-sized resin particles to form a micro-convex structure, it achieves an air-locking effect on the water contact surface, overcoming the physical limitation that "hydrophobicity necessarily means smoothness." Second, by adjusting the ratio of the anti-slip resin and using a high-solids water-based resin formulation, along with controlling the leveling properties with anionic dispersants, it solves the problems of reduced coating thickness and increased resin costs for paperboard, achieving cross-temperature stability. This not only effectively meets the high-slope requirements of food production lines but also adapts to demanding scenarios such as cold chain warehousing and medical transportation. Furthermore, this invention utilizes a low-temperature grinding and embedding process to directionally embed modified particles into the paperboard fibers, avoiding resin carbonization caused by high temperatures, reducing particle migration, enhancing the anti-slip structure, and meeting the requirements of automated high-slope production lines. The entire production process of this invention is simple and easy to mass-produce, completing coating and curing in a single step, reducing energy consumption by 40%. The resulting waterproof and anti-slip paperboard exhibits significantly improved anti-slip reliability in slope scenarios, overcoming the mutual exclusion of waterproof and anti-slip performance, and achieving synergistic dual-function on the paperboard surface. This invention possesses significant technological and market promotion value. Attached Figure Description

[0018] Figure 1 The anti-slip performance test results of the paperboard were obtained through the preparation process of this invention; Figure 2 The waterproof performance test results of the cardboard were obtained through the preparation process of this invention. Detailed Implementation

[0019] The preferred embodiments of the present invention will now be described in detail so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0020] Example: This invention addresses the performance contradiction of waterproofing and anti-slip properties in existing technologies by providing a waterproof and anti-slip cardboard, which is obtained through the following preparation process.

[0021] Step 1, particle premixing: Premix 40% by weight of type 1207 acrylic emulsion, 20% by weight of type 1209 acrylic emulsion, and 15% by weight of waterproof wax. The second step is particle grinding and dispersion: Grind the particles to a particle size ≤15um in a three-roll mill at a low temperature of 55℃ to form a stable suspension. The third step is to continue dispersing: 20% by weight of anti-slip resin, 5% by weight of defoamer and leveling agent were added to a dispersion tank and dispersed at 800 rpm for 30 minutes. Then, the stable suspension obtained in the previous step was added and the dispersion time was continued for at least 15 minutes to obtain a water-based environmentally friendly coating. Considering that if the solid content is less than 45%, the coating saturation will be insufficient and the anti-slip / waterproof performance will decline, the anti-slip resin selected in this embodiment is a water-based epoxy resin with a solid content of ≥45% and a particle size controlled at 10~15um. Step 4, Cardboard coating: Using a microgravure coating machine, the above-obtained water-based environmentally friendly coating was applied at a viscosity controlled at 3500±500 cps (25℃) and a wet coating weight of 10 g / m². 2 The coating speed is controlled at 60m / min, and the paperboard is coated by rolling at a low temperature of 60℃ to oriented and embed the modified particles into the paperboard fibers. Step 5: Allow to cure naturally at room temperature. When the paperboard is coated, it is initially dry and there are no problems with handling and stacking. Through natural drying, it is normally dried for about 5 minutes to form a composite functional layer with a thickness of 10~15um, and finally obtains waterproof and non-slip paperboard.

[0022] The waterproof and anti-slip cardboard products obtained above were tested for their waterproof and anti-slip properties. The specific testing process is as follows: like Figure 1 The diagram shows the anti-slip performance test of the cardboard product in this embodiment. A waterproof and anti-slip cardboard A, prepared using the process of this invention, is clamped onto a test rotating plate. Another waterproof and anti-slip cardboard B, also prepared using the process of this invention, is placed on top of it, with a 300g weight placed on top of B. For ease of observation, the area of ​​the upper cardboard B is smaller than that of the lower cardboard A. The vertical screw on one side is activated, causing the test rotating plate to rotate and rise. Simultaneously, the cardboard A on the upper side gradually rotates and rises. As the plate rises on one side, the angle between the test rotating plate and the horizontal plane increases. The upper cardboard B and the weight remain relatively stationary with respect to the lower cardboard A only through static friction. A level is placed on one side of the test rotating plate to measure the rotation angle. When the rotation angle of the test rotating plate reaches 30.1°... 0At this time, the upper cardboard B and the lower cardboard A begin to slide relative to each other, thus allowing for a direct test that the waterproof and anti-slip cardboard obtained by this invention has excellent anti-slip performance.

[0023] like Figure 2 As shown, this is a test result of the waterproof performance of the cardboard product in this embodiment. Water was splashed onto the surface of the waterproof and non-slip cardboard obtained by the preparation process of this invention, and then the water penetration was observed. It can be seen intuitively that the cardboard is not hydrophilic, but similar to a hydrophobic structure. Water droplets will not penetrate into the inner wall of the cardboard, and this state is maintained even after ten minutes. Water droplets can not penetrate into the interior of the cardboard for a long time. Therefore, it can be intuitively tested that the waterproof and non-slip cardboard obtained by this invention has excellent waterproof performance.

[0024] Therefore, the paperboard prepared by the present invention overcomes the performance contradiction of incompatibility between waterproof and anti-slip in the prior art, and achieves the synergistic effect of waterproof and anti-slip dual functions. It is very suitable for high-slope production lines or high-requirement scenarios such as cold chain warehousing and medical transportation. The applicant has also introduced mass production of this paperboard product, and the market prospects are very good.

[0025] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A manufacturing process for waterproof and non-slip cardboard, characterized in that: The preparation process includes the following steps. S1. Premix the functional granules and waterproof wax at a mass ratio of 4:1; S2. Grind the mixture from S1 in a three-roll mill until the particle size is ≤15µm to form a stable suspension; S3. Add the anti-slip resin and other additives to the dispersion tank according to the mass ratio for dispersion, and then add the suspension obtained in S2 to continue dispersion to obtain a water-based environmentally friendly coating. S4. Using a micro-gravure coating machine, apply the water-based environmentally friendly coating obtained in S3 to the paperboard under the settings of viscosity, wet coating amount and coating speed; S5. The coated paperboard is naturally dried to form a composite functional layer with a thickness of 10~15um, ultimately obtaining paperboard with waterproof and anti-slip functions.

2. The manufacturing process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: The functional particles in S1 are a combination of type 1207 acrylic emulsion and type 1209 acrylic emulsion.

3. The preparation process of a waterproof and non-slip cardboard according to claim 2, characterized in that: The ratio of the 1207 type acrylic emulsion to the 1209 type acrylic emulsion is 2:

1.

4. The preparation process of a waterproof and non-slip cardboard according to claim 1, characterized in that: In step S2, the grinding temperature inside the three-roll mill needs to be controlled within a low-temperature range of 50~60℃.

5. The preparation process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: The dispersion conditions of the anti-slip resin and other additives in the S3 dispersion tank are controlled at a speed of 800 rpm and a dispersion time of 30 minutes. After adding the S2 suspension, the dispersion time continues for at least 15 minutes.

6. The manufacturing process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: The anti-slip resin in S3 is selected as a water-based epoxy resin with a solid content ≥45% and a particle size controlled at 10~15um.

7. The manufacturing process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: Other additives in S3 are selected from defoamers and leveling agents.

8. The preparation process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: The viscosity of the water-based environmentally friendly coating in S4 is controlled at 3500±500 cps, and the wet coating amount is 10 g / m². 2 The coating speed is controlled at 60m / min, and the coating is rolled at 60℃.

9. The manufacturing process of a waterproof and anti-slip cardboard according to claim 1, characterized in that: The functional particles, waterproof wax, anti-slip resin, and other additives are present in mass ratios of 60%, 15%, 20%, and 5%, respectively.

10. The application of a process for preparing waterproof and non-slip cardboard as described in any one of claims 1 to 9 in the preparation of refrigerated and frozen product packaging boxes.

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