High-strength waterproof composite paper tray and production method thereof

Abstract

The invention particularly relates to a high-strength waterproof composite paper tray and a production method thereof, the high-strength waterproof composite paper tray comprises a tray main body, the tray main body is made of a paper cardboard, and the paper cardboard is any one of a corrugated board, a honeycomb paperboard and a sand pipe hardboard. Surface paper adheres to the surface of the paper cardboard through an adhesive, the surface of the surface paper is coated with waterproof paint, and a waterproof coating is formed on the surface of the surface paper after the waterproof paint is subjected to calendering treatment. The paper cardboard is adopted to replace a traditional wood board and plastic, the requirements for high compressive strength and stability of the tray are met, meanwhile, the waterproof coating is arranged on the surface of the paper cardboard, the waterproofness and weather resistance of the paper tray are remarkably improved, and the paper tray can adapt to use under different environment temperature and humidity, is not prone to damage and can be recycled, and the cost is reduced. And the production cost is effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of paper pallet production, and in particular to a high-strength waterproof composite paper pallet and a production method thereof. Background Art

[0002] At present, the commonly used intermodal pallets on the market include wooden pallets, plastic pallets, metal pallets, paper pallets and composite pallets made of other composite materials. Among them, wooden pallets have become the first choice for various industries due to their high comprehensive cost-effectiveness. However, the processing of wooden pallets requires a large amount of wood resources, which directly consumes forest resources. It is difficult to meet the green environmental protection and sustainable development requirements of the dual carbon goals of "carbon neutrality" and "carbon peak" proposed at home and abroad. Therefore, how to reduce the use of wooden pallets has also become one of the key issues considered by various industries. In contrast, most paper pallets are made of recyclable paper materials and do not directly consume forest resources. Choosing to use paper pallets to replace some wooden pallets has become an obvious trend in the industry. However, in the current promotion and use of paper pallets, due to the low strength and easy moisture absorption of paper materials, paper pallets have problems such as low compressive strength and poor waterproofness. For this reason, it is urgent to improve the compressive strength and waterproofness of paper pallets to enhance the applicability of paper pallets in logistics and transportation, and provide guarantees for the wider promotion and application of paper pallets. Summary of the invention

[0003] The purpose of the present invention is to solve the above-mentioned deficiencies in the prior art and to provide a high-strength waterproof composite paper pallet and a production method thereof, aiming to improve the compressive strength and waterproofness of the paper pallet.

[0004] The objective of the present invention is achieved through the following technical scheme: a high-strength waterproof composite paper pallet, comprising a pallet body, the pallet body being made of a paper pallet, the surface of the paper pallet being adhered with a face paper by an adhesive, the surface of the face paper being coated with a waterproof coating, and the waterproof coating being calendered to form a waterproof coating on the surface of the face paper.

[0005] Furthermore, the adhesive comprises the following raw materials in percentage by mass: 12-16% polyvinyl chloride emulsion, 7-9% vinyl acetate, 0.5-1% defoaming agent, 0.1-1% preservative, and the rest is deionized water.

[0006] Furthermore, the waterproof coating comprises the following raw materials in percentage by mass: 58-66% waterborne polyurethane resin, 1-21% waterborne acrylic resin emulsion, 0.7-3% polyethylene wax emulsion, 0.5-2.5% dispersant, 0.3-2% defoaming agent, 0.3-2% neutralizer, 0.3-1% wetting agent, and the rest is deionized water.

[0007] Furthermore, the preparation method of the waterproof coating comprises the following steps: (1) adding a dispersant, a wetting agent and a polyethylene wax emulsion to a container containing deionized water in sequence, stirring and dispersing the mixture to obtain a mixed solution; (2) adding an aqueous polyurethane resin to the mixed solution obtained in step (1), stirring the mixture to obtain a mixed solution, and then adding an aqueous acrylic resin emulsion, stirring the mixture to obtain a mixed solution; (3) adding a neutralizing agent to adjust the pH of the solution to 8-9; and (4) adding a defoaming agent and continuing to stir the mixture until the mixture is free of bubbles, and filtering the mixture to obtain the waterproof coating.

[0008] In the present invention, the waterproof coating uses water-based polyurethane resin as the main film-forming substance, which can ensure that the coating has good water resistance and wear resistance; the addition of water-based acrylic resin emulsion and polyethylene wax helps to improve the adhesion between the waterproof coating and the facial paper, so that it can form a firm protective film on the facial paper, while improving the hardness and wear resistance of the waterproof coating. The dispersant helps to reduce the surface tension of the system, so that each component is evenly dispersed in the slurry system, and ensures the uniformity of the coating. The waterproof coating obtained by the above formula of the present invention has good fluidity and moderate viscosity, can form a high-quality continuous waterproof coating on the surface of the facial paper, and the waterproof coating has high uniformity, good wear resistance and strong waterproofness.

[0009] In the present invention, by spraying a waterproof coating on the surface of the facial paper, the waterproof coating can improve the moisture resistance of the facial paper, ensuring that it is not easily damaged in a humid environment. Then, by calendering treatment, the waterproof slurry is distributed more evenly and tightly on the facial paper, thereby further improving the waterproof ability of the facial paper. And after the calendering treatment, the surface smoothness of the facial paper is significantly improved.

[0010] Furthermore, the paper cardboard is any one of corrugated cardboard, honeycomb cardboard, and sand tube cardboard.

[0011] Furthermore, the bursting strength of the corrugated paperboard is 23-25 ​​kgf / cm 2 , the edge compression strength is 12-15kN / m; or, the compressive strength of the honeycomb paperboard is above 5000kg, and the tensile strength is 5-10MPa; or, the compressive strength of the sand tube cardboard is 550-700N / cm, and the bending strength is 300-450kgf / cm 2 .

[0012] Furthermore, the tray main board includes a panel, a reinforcing plate is arranged on the top of the panel, and the panel is folded upward around the reinforcing plate and arranged around the reinforcing plate to form side blocking parts around the reinforcing plate.

[0013] Furthermore, at least one supporting portion is provided at the bottom of the tray body.

[0014] Furthermore, the reinforcing plate is made of sand tube cardboard. The sand tube cardboard includes two layers of paper and a sand tube paper core arranged between the two layers of paper. Among them, the surface paper is 300g optimized kraft paper, and the sand tube paper core is 500g. The sand tube paper core and the surface paper are bonded with an adhesive, and the adhesive includes the following raw materials in parts by weight: 450 parts of corner powder, 26 parts of nitrate, 18 parts of borax and deionized water, and the deionized water is 22-32% of the total mass of corner powder, nitrate and borax. In the formula of the adhesive, the amount of deionized water is adjusted according to the ambient temperature when the adhesive is used.

[0015] Furthermore, the support part is made of a honeycomb board, which includes a honeycomb core paper and two layers of surface paper, the overlapping parts of the two layers of surface paper are bonded to the bottom of the honeycomb core paper, and the two ends of the surface paper are folded upward and covered on the peripheral surface and top surface of the honeycomb core paper, forming a six-sided cylindrical structure.

[0016] The present invention also provides a method for preparing the above-mentioned high-strength waterproof composite paper pallet, comprising the following steps:

[0017] (1) Spraying waterproof coating on the surface paper through a coating machine, and then calendering through a calendering machine to solidify the waterproof coating on the surface of the surface paper to form a waterproof coating;

[0018] (2) applying adhesive to the surface of the face paper away from the waterproof coating, and adhering the face paper to the surface of the paper cardboard to obtain a waterproof paper cardboard for standby use;

[0019] (3) Cut the waterproof paper pallet according to the size specifications of the pallet body, preset folding lines at corresponding positions, and then fold and bond them according to the folding lines to obtain the high-strength waterproof composite paper pallet.

[0020] Furthermore, in step (1), the calendering treatment is performed by a calendering machine, the calendering pressure is 110-130 kN / m, the temperature is 105-115° C., and the calendering speed is 90-110 m / min.

[0021] The beneficial effects of the present invention are as follows: (1) The present invention can significantly improve the moisture resistance, waterproofness and anti-slip properties of the surface paper by spraying a waterproof coating on the surface of the surface paper and performing a calendering treatment on the surface paper, so that the paper pallet can be suitable for storage and transportation requirements in different environments, thereby solving the problem that the existing paper pallet is easy to absorb moisture.

[0022] (2) The adhesive obtained by the present invention using polyvinyl chloride emulsion and vinyl acetate as main raw materials has the characteristics of strong adhesion and stable storage performance. It is not easy to bubble and debond when used for bonding facial tissue and paper materials, and the production cost is low.

[0023] (3) The present invention uses corrugated paperboard, honeycomb paperboard and sand tube cardboard as paper substrates to make a composite paper pallet, which can significantly improve the compressive strength and overall structural stability of the paper pallet. According to tests, its static load capacity reaches 4000kgf, and the overall mass of the pallet is reduced.

[0024] (4) The paper pallets of the present invention are made of recyclable paper materials, which effectively promotes the recycling of resources and can achieve customized production of pallets while ensuring production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the assembly process of the paper pallet described in Example 2.

[0026] 1. Pallet body; 10. Panel; 100. Face paper; 101. Side stop; 11. Reinforcement plate; 110. Connecting plate; 111. X-shaped support frame; 112. Crossbeam; 13. Support part; 130. Honeycomb core paper. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0028] Example 1

[0029] The present embodiment provides a high-strength waterproof composite paper pallet, including a pallet body, the pallet body is made of a paper pallet, the surface of the paper pallet is adhered with a face paper by an adhesive, the surface of the face paper is coated with a waterproof coating, and the waterproof coating forms a waterproof coating on the surface of the face paper after calendering.

[0030] In this embodiment, the paper cardboard is a corrugated paperboard. Specifically, the corrugated paperboard includes a face paper, a first flute, a middle paper, a second flute and a lining paper arranged in order from top to bottom, and the face paper, the first flute, the middle paper, the second flute and the lining paper are all bonded and pressed together by an adhesive. Among them, the face paper is a 300g optimized kraft cardboard with a bursting strength of 12kgf / cm 2 , ring compression strength is 67kgf / 152mm, surface water absorption is 20g / m 2 The first and second fluted paper are both 140g high-strength core, the ring crush strength is 22kgf / 152mm, and the burst strength is 2.7kgf / cm 2 , water absorption is 22g / m 2 The middle paper is 120g optimized kraft paper, with a ring crush strength of 19kgf / 152mm and a burst strength of 2.5kgf / cm 2 , water absorption is 24g / m 2The inner paper is 230g optimized kraft paper, with a ring crush strength of 53kgf / 152mm and a burst strength of 9kgf / cm 2 , water absorption is 22g / m 2 .

[0031] Furthermore, the adhesive comprises the following raw material compositions in percentage by mass: 13% polyvinyl chloride emulsion, 7% vinyl acetate, 0.5% organosilicon defoamer, 0.2% methylchloroisothiazolinone, and the remainder is deionized water.

[0032] Furthermore, the waterproof coating comprises the following raw materials in percentage by mass: 60% waterborne polyurethane resin, 10% waterborne acrylic resin emulsion, 1% polyethylene wax emulsion, 1% dispersant, 0.8% defoamer, 0.6% neutralizer, 0.5% wetting agent, and the rest is deionized water. The molecular weight of the waterborne polyurethane resin is 5300Da (Kodak P-50), the viscosity of the waterborne acrylic resin emulsion is 300cPs, the dispersant is BYK-180, the defoamer is BYK-025, the neutralizer is triethanolamine, and the wetting agent is surfynol 104H.

[0033] Furthermore, the preparation method of the waterproof coating comprises the following steps: (1) adding a dispersant, a wetting agent and a polyethylene wax emulsion to a container containing deionized water in sequence, and stirring and dispersing the mixture at a rotation speed of 350 rpm to obtain a mixed solution; (2) adding an aqueous polyurethane resin to the mixed solution obtained in step (1), stirring at a rotation speed of 725 rpm for more than 60 minutes to ensure uniform mixing, and then adding an aqueous acrylic resin emulsion, and continuing to stir and disperse the mixture evenly; (3) adding a neutralizing agent to adjust the pH of the solution to 9; (4) adding a defoaming agent and continuing to stir until there is no foam, and filtering to obtain the waterproof coating.

[0034] In this embodiment, the waterproof coating has a solid content of 44%, a pH of 9, and a viscosity of 3000 CPS.

[0035] The method for preparing the high-strength waterproof composite paper pallet described in this embodiment comprises the following steps:

[0036] (1) Spraying waterproof coating on the surface paper through a coating machine, and then calendering through a calendering machine to solidify the waterproof coating on the surface of the surface paper to form a waterproof coating;

[0037] (2) applying adhesive to the surface of the face paper away from the waterproof coating, and adhering the face paper to the surface of the paper cardboard to obtain a waterproof paper cardboard for standby use;

[0038] (3) Cut the waterproof paper pallet according to the size specifications of the pallet body, preset folding lines at corresponding positions, and then fold and bond them according to the folding lines to obtain the high-strength waterproof composite paper pallet.

[0039] Furthermore, in step (1), the spraying humidity of the coating machine is 100 m / min, the coating accuracy is 21 g / m2, and the temperature is 105°C; in the calendering treatment, the calender roller diameter is 1200 mm, the calendering pressure is 120 kN / m, the temperature is 110°C, and the calendering speed is 100 m / min.

[0040] The surface paper obtained by spraying and calendering the waterproof coating in this embodiment has been tested. The thickness of the waterproof coating is 0.3μm, the surface roughness of the surface paper is 3μm, the tensile strength is 12MPa, the temperature range is -5℃~80℃, the water content is 7%, the tightness is 0.89G / cm², the wear test is more than 2500 times, and the water vapor permeability is 3g / (m²·24h). Furthermore, the performance of the corrugated paperboard with waterproof coating surface paper obtained in this embodiment is tested. The thickness of the corrugated paperboard is 6.7mm, and the bursting strength is 24kgf / cm 2 The edge compression strength is 13kN / m, the moisture content is 7%, and the folding endurance is more than 100 times.

[0041] Furthermore, in step (3), the pallet body includes a panel and four support parts respectively arranged at four top corners of the bottom of the panel, and the panel and the support parts are both made of the waterproof paper pallet obtained in step (2) by folding and bonding.

[0042] The following results were obtained by testing the finished product of the paper pallet made in this embodiment: the overall compressive strength of the paper pallet is 1856kg, and when stored in a temperature range of -40℃ to 70℃, there is no debonding or loose bonding between the layers of the paper pallet, indicating that it has a wide operating temperature range and can be used for storage and transportation of items in different environments. In terms of moisture resistance test, the paper pallet was placed in an environment with a relative humidity of 95% and a temperature of 40℃ for 24 hours, and its overall compressive strength was equivalent to 94% of the product before the test.

[0043] Example 2

[0044] like Figure 1 As shown, this embodiment provides a high-strength waterproof composite paper pallet, including a pallet main body 1, the pallet main board 1 includes a panel 10, a reinforcing plate 11 is arranged on the top of the panel 10, and the panel 10 is folded upward around the reinforcing plate 11 and surrounded by the reinforcing plate 11 to form side guards 101 around the reinforcing plate 11.

[0045] Furthermore, the reinforcing plate 11 has four connecting plates 110 connected end to end in sequence, and an X-shaped support frame 111 is provided inside the reinforcing plate 11, and the ends of the X-shaped support frame 111 are respectively clamped at the connection between two adjacent connecting plates 110; the reinforcing plate 11 is also provided with a cross beam 112, and the cross beam 112 runs through the middle of the X-shaped support frame 111, and the two ends are respectively clamped at the two opposite connecting plates 110.

[0046] Furthermore, three support groups are provided at the bottom of the panel 10, and the three support groups are equidistantly distributed along the width direction of the panel, and the support group has three equidistantly distributed support parts 13 along the length direction of the panel. In this embodiment, each support part 13 is respectively fixed to the bottom wall of the panel 10 by adhesive.

[0047] Furthermore, the adhesive comprises the following raw material compositions in percentage by mass: 14% polyvinyl chloride emulsion, 8% vinyl acetate, 0.8% defoaming agent, 0.7% preservative, and the remainder is deionized water.

[0048] Furthermore, the waterproof coating comprises the following raw materials in percentage by mass: 62% waterborne polyurethane resin, 11% waterborne acrylic resin emulsion, 1.5% polyethylene wax emulsion, 1.2% dispersant, 1% defoamer, 1.2% neutralizer, 0.51% wetting agent, and the rest is deionized water. The molecular weight of the waterborne polyurethane resin is 5300Da (Kodak P-50), the viscosity of the waterborne acrylic resin emulsion is 300cPs, the dispersant is BYK-180, the defoamer is BYK-025, the neutralizer is triethanolamine, and the wetting agent is surfynol 104H.

[0049] Furthermore, the preparation method of the waterproof coating comprises the following steps: (1) adding a dispersant, a wetting agent and a polyethylene wax emulsion to a container containing deionized water in sequence, and stirring and dispersing the mixture at a rotation speed of 350 rpm to obtain a mixed solution; (2) adding an aqueous polyurethane resin to the mixed solution obtained in step (1), stirring at a rotation speed of 725 rpm for more than 60 minutes to ensure that the mixture is evenly mixed, and then adding an aqueous acrylic resin emulsion, and continuing to stir and disperse the mixture evenly; (3) adding a neutralizing agent to adjust the pH of the solution to 9; (4) adding a defoaming agent and continuing to stir until there is no foam, and filtering to obtain the waterproof coating.

[0050] In this embodiment, the panel 10 is formed by overlapping two pieces of corrugated paperboard, and the sides of the two pieces of corrugated paperboard close to each other are coated with adhesive. The corrugated paperboard includes face paper, first fluted paper, middle paper, second fluted paper and inner paper arranged in order from top to bottom, and the face paper, first fluted paper, middle paper, second fluted paper and inner paper are all bonded and pressed together by adhesive. The face paper is 300g optimized kraft card with a bursting strength of 12kgf / cm 2 , ring compression strength is 67kgf / 152mm, surface water absorption is 20g / m 2 The first and second fluted paper are both 140g high-strength core, the ring crush strength is 22kgf / 152mm, and the burst strength is 2.7kgf / cm 2 , water absorption is 22g / m 2 The middle paper is 120g optimized kraft paper, with a ring crush strength of 19kgf / 152mm and a burst strength of 2.5kgf / cm 2 , water absorption is 24g / m 2 The inner paper is 230g optimized kraft paper, with a ring crush strength of 53kgf / 152mm and a burst strength of 9kgf / cm 2 , water absorption is 22g / m 2 .

[0051] Furthermore, the reinforcing plate 11 is made of sand tube cardboard. The sand tube cardboard includes two layers of face paper 100 and a sand tube paper core arranged between the two layers of face paper 100. Among them, the face paper 100 is the same as that in Example 1, and the sand tube paper core is 500g. The sand tube paper core and the face paper 100 are bonded with an adhesive, and the adhesive includes the following raw materials in parts by weight: 450 parts of corner powder, 26 parts of nitrate, 18 parts of borax and deionized water, and the deionized water is 22-32% of the total mass of the corner powder, nitrate and borax. In this embodiment, the ambient temperature is 30 degrees, and the amount of deionized water is 30% of the total mass of the corner powder, nitrate and borax. The sand tube cardboard thus obtained was tested, and its compressive strength was 600N / cm (size 200*100*5mm), and the bending strength was 380kgf / cm 2 , flexural modulus is 3000MPa, bulk density is 850kg / m 3 , the bonding strength is 1650N / m.

[0052] Furthermore, the support portion 13 is made of a honeycomb board. The honeycomb board includes a honeycomb core paper 130 and two layers of face paper 100. The overlapping parts of the two layers of face paper 100 are bonded to the bottom of the honeycomb core paper 130, and the two ends of the face paper 100 are respectively folded upward and wrapped around the circumference and top surface of the honeycomb core paper 130 to form a six-sided cylindrical structure. In this embodiment, the size of the support portion 13 is 180*90*50mm. Among them, the face paper 100 is the same as that in Example 1, the honeycomb core paper 130 is a 140g high-strength core, the ring crush strength is 22kgf / 152mm, and the burst strength is 2.7kgf / cm 2 , water absorption is 22g / m 2 The face paper 100 and the honeycomb core paper 130 are bonded and pressed together by an adhesive. The adhesive coating process is completed by a coating device. The adhesive coating amount is 250g / m 2 , production speed is 40m / s, curing temperature of adhesive is 120℃, lamination pressure is 4kg / cm 2 , molding pressure is 2kg / cm 2 The compressive strength of the honeycomb panel in this embodiment is 5000kg, the compressive strength is 7MPa, the flexural strength is 45MPa, and the moisture content is 12%.

[0053] The preparation method of the high-strength waterproof composite paper pallet described in this embodiment includes the following steps: (1) spraying a waterproof coating on the surface paper 100 by a coating machine, and then calendering it by a calendering machine so that the waterproof coating is solidified on the surface of the surface paper 100 to form a waterproof coating; (2) coating an adhesive on the surface of the surface paper 100 away from the waterproof coating, and adhering the surface paper 100 to the surface of the paper pallet to obtain a waterproof paper pallet for standby use; (3) coating the surface of the panel with an adhesive, and then pressing the reinforcing plate and the panel together, and then adhering the panel to the support part on the side away from the reinforcing plate, and folding the part of the panel located around the reinforcing plate in the direction away from the support part and bonding it to obtain the high-strength waterproof composite paper pallet. Furthermore, in step (1), the spraying humidity of the coating machine is 100m / min, and the coating accuracy is 21g / m 2 , the temperature is 105℃; in the calendering treatment, the calender roller diameter is 1200mm, the calendering pressure is 120kN / m, the temperature is 110℃, and the calendering speed is 100m / min.

[0054] The high-strength waterproof composite paper pallet prepared by the above method in this embodiment obtained the following results after finished product testing: its overall compressive strength is greater than 4000kg, and when stored in a temperature range of -40℃~70℃, there is no debonding or loose bonding between the layers of the paper pallet through the adhesive, indicating that it has a wide operating temperature range and can be used for storage and transportation of items in different environments. In terms of moisture resistance test, the paper pallet was placed under a relative humidity of 95% and a temperature of 40℃ for 24 hours, and the overall compressive strength was equivalent to 96% of the product before the test. In terms of waterproof performance test, the support part was placed upward, and the spray test was used to evaluate its waterproof effect. After continuous spraying for 30 minutes, there was no obvious water seepage on the surface of the paper pallet.

[0055] The above specific embodiments are further explanations of the technical solutions and beneficial effects of the present invention, and are not limitations of the implementation methods. For those skilled in the art, any obvious replacements that do not depart from the concept of the present invention are within the protection scope of the present invention.

Claims

1. A high-strength waterproof composite paper pallet, characterized by: The invention comprises a pallet body, which is made of a paper pallet, the surface of which is adhered with a face paper by an adhesive, the surface of which is coated with a waterproof coating, and the waterproof coating forms a waterproof coating on the surface of the face paper after calendering.

2. The high-strength waterproof composite paper pallet according to claim 1, characterized in that: The adhesive comprises the following raw materials in percentage by mass: 12-16% polyvinyl chloride emulsion, 7-9% vinyl acetate, 0.5-1% defoamer, 0.1-1% preservative, and the rest is deionized water.

3. The high-strength waterproof composite paper pallet according to claim 1 is characterized in that: The waterproof coating comprises the following raw materials in percentage by mass: 58-66% of waterborne polyurethane resin, 1-21% of waterborne acrylic resin emulsion, 0.7-3% of polyethylene wax emulsion, 0.5-2.5% of dispersant, 0.3-2% of defoamer, 0.3-2% of neutralizer, 0.3-1% of wetting agent, and the rest is deionized water.

4. The high-strength waterproof composite paper pallet according to claim 3 is characterized in that: The preparation method of the waterproof coating comprises the following steps: (1) adding a dispersant, a wetting agent and a polyethylene wax emulsion into a container containing deionized water in sequence, stirring and dispersing the mixture to obtain a mixed solution; (2) adding an aqueous polyurethane resin into the mixed solution obtained in step (1), stirring the mixture to obtain a mixed solution, and then adding an aqueous acrylic resin emulsion, stirring the mixture to obtain a mixed solution; (3) adding a neutralizing agent to adjust the pH value of the solution to 8-9; and (4) adding a defoaming agent and continuing to stir the mixture until there is no foam, and filtering the mixture to obtain the waterproof coating.

5. The high-strength waterproof composite paper pallet according to claim 1, characterized in that: The paper cardboard is any one of corrugated cardboard, honeycomb cardboard, and sand tube cardboard.

6. The high-strength waterproof composite paper pallet according to claim 5, characterized in that: The bursting strength of the corrugated paperboard is 23-25kgf / cm 2 , the edge compression strength is 12-15kN / m; or, the compressive strength of the honeycomb paperboard is above 5000kg, and the tensile strength is 5-10MPa; or, the compressive strength of the sand tube cardboard is 550-700N / cm, and the bending strength is 300-450kgf / cm 2 .

7. The high-strength waterproof composite paper pallet according to any one of claims 1 to 6, characterized in that: The tray main board comprises a panel, a reinforcing plate is arranged on the top of the panel, and the panel is folded upwards around the reinforcing plate and arranged around the reinforcing plate.

8. The high-strength waterproof composite paper pallet according to any one of claims 1 to 6, characterized in that: At least one supporting portion is disposed at the bottom of the tray body.

9. The method for preparing a high-strength waterproof composite paper pallet according to any one of claims 1 to 6, characterized in that: The steps include: (1) Spraying waterproof coating on the surface paper through a coating machine, and then calendering through a calendering machine to solidify the waterproof coating on the surface of the surface paper to form a waterproof coating; (2) applying adhesive to the surface of the face paper away from the waterproof coating, and adhering the face paper to the surface of the paper cardboard to obtain a waterproof paper cardboard for standby use; (3) Cut the waterproof paper pallet according to the size specifications of the pallet body, preset folding lines at corresponding positions, and then fold and bond them according to the folding lines to obtain the high-strength waterproof composite paper pallet.

10. The high-strength waterproof composite paper pallet according to claim 9, characterized in that: In step (1), the calendering treatment is performed by a calendering machine, the calendering pressure is 110-130 kN / m, the temperature is 105-115° C., and the calendering speed is 90-110 m / min.

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