Paper pulp molded product glue brushing and bonding method and paper pulp molded product

Abstract

The invention relates to a paper pulp molded product glue brushing and bonding method and a paper pulp molded product, and the paper pulp molded product glue brushing and bonding method comprises the following steps: forming: forming a paper pulp supporting plate on which a plurality of paper pulp supports are distributed at intervals; brushing glue: brushing a glue layer for bonding a paper card on a paper pulp support on the paper pulp support plate; edge cutting: cutting edges of the paper pulp supporting plate to form a plurality of paper pulp supports; placing a paper card; and machine bonding: bonding the paper card and the paper pulp support together. According to the glue brushing and bonding method for the paper pulp molded product, due to the fact that the number of glue brushing row modulus of the product is large, glue brushing is conducted after each product is trimmed, taking and placing consume time, and staff operation is not convenient, the glue brushing process and the trimming process are exchanged, glue brushing is conducted before the trimming process, the time for subsequent workers to take and place a single paper pulp support is shortened, and the overall efficiency is improved; the paper card and the paper pulp support can be bonded together simply and quickly, the efficiency of the production process is high, and the packaging cost of paper pulp molded products can be reduced.

Description

Technical Field

[0001] The present application relates to the field of paper-plastic technology, and in particular to a method for gluing pulp molded products and pulp molded products. Background Art

[0003] Pulp molding (paper molding) is a technology that uses waste paper as raw material (including board paper, waste carton paper, waste white edge paper, etc.), adds some moisture-proof agent or waterproof agent, and shapes paper products of a certain shape by special molds on a molding machine. These products can be used as packaging pads for eggs, fruits, precision devices, fragile glass, ceramic products, handicrafts, etc., and have good cushioning and protection properties. In a type of pulp molding products, it usually involves the bonding step of paper card and pulp tray to ensure that the two can be firmly combined to form an integral product structure, thereby forming a suitable accommodation space. The bonding of paper card and pulp tray is a key step, which is directly related to the structural strength, durability and overall quality of the product. However, due to the limitations of some processes, low efficiency and high labor costs, the cost of the entire set of packaging has doubled. In the existing process, when pulp molding products are produced, after the pulp tray is formed by molding, it is necessary to use a trimming process to cut off the excess part of the edge of the product, and then apply glue to bond the paper card. If each product is trimmed and then glued, it will take time to pick up and put away, which is inconvenient for employees to operate and has extremely low operating efficiency. Summary of the invention

[0004] Based on this, it is necessary to provide a method for gluing pulp molded products and pulp molded products with high production efficiency and reduced packaging costs. The present invention mainly relates to a packaging process, which aims to bond paper cards and pulp trays together in a simple and quick way.

[0005] The present application provides a method for gluing a pulp molded product, comprising the following steps:

[0006] Forming: forming a pulp support plate with a plurality of pulp supports spaced apart;

[0007] Glue brushing: brush a glue layer for bonding paper cards on the pulp tray;

[0008] Trimming: trimming the pulp tray to form multiple pulp trays;

[0009] Place the paper card: align the paper card and place it on the glue layer of the pulp tray;

[0010] Machine bonding: Use bonding equipment to heat and apply pressure to melt the glue layer, so that the paper card and the pulp tray are bonded together.

[0011] In one of the embodiments, in the glue-brushing step, a milky white water-based hot melt adhesive is used.

[0012] In one embodiment, the ingredients of the water-based hot melt adhesive include: water-based urethane dispersion: 40%-42%, deionized water: 58%-60%, the pH value of 1% aqueous solution of the water-based hot melt adhesive is 7-9, the initial boiling point of the water-based hot melt adhesive is 100°C, the secondary heating melting point is 120°C, and the dynamic viscosity is: <250mPa.s.

[0013] In one of the embodiments, in the glue-brushing step, the position size of the glue-brushing silk-screen screen is 30 mm larger than the edge of the pulp support plate of the glue-brushing product and smaller than 50 mm.

[0014] In one embodiment, the mesh number of the glue-brushing silk-screen printing screen is selected to be an 80-mode screen, the thickness of the glue-brushing silk-screen printing screen is 0.3 mm, and the thickness of the silk-screen glue position is 0.2 mm.

[0015] In one of the embodiments, the thickness of the adhesive layer formed after the water-based hot melt adhesive is dried is controlled between 0.10-0.15 mm.

[0016] In one of the embodiments, after applying the glue, the glue layer on the pulp support plate is dried by natural drying or heating drying.

[0017] In one embodiment, the heating and drying is performed using a drying line, the heating section of the drying line shall not be less than 5 meters, the drying temperature of the heating section is 80 degrees Celsius, and the drying line speed is 5m / min.

[0018] In one embodiment, during natural drying, the air humidity is 40%-80%, the temperature is 15° C.-30° C., and the drying time is 12-18 hours.

[0019] The present application also provides a pulp molded product, which is formed by bonding a pulp support plate and a paper card using the glue bonding method for pulp molded products as described in any of the above embodiments.

[0020] The above-mentioned method of gluing and bonding pulp molded products takes into account that the number of product gluing rows is relatively large. If each product is glued after trimming, it will be time-consuming to pick up and put down, which is inconvenient for employees to operate. Therefore, the gluing process is swapped with the trimming process, and glue is applied before the trimming process. This reduces the time for subsequent workers to pick up and put down a single pulp tray, improves the overall efficiency, and can simply and quickly glue the paper card and the pulp tray together. The production process is highly efficient and can reduce the packaging cost of pulp molded products. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a step diagram of a method for gluing a pulp molded product according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to facilitate the understanding of the present invention, in order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention, and the preferred embodiments of the present invention are given in the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood. The present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited to the specific embodiments disclosed below. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art of the present invention. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0023] This application provides a method for gluing pulp molded products. Figure 1 The method for gluing pulp molding products comprises the following steps:

[0024] S1: forming: forming a pulp support plate having a plurality of pulp supports spaced apart;

[0025] A pulp tray with multiple pulp trays spaced apart is formed by using a pulp molding process. Each pulp tray is used to form a single pulp molded finished product later. In order to facilitate mass production, in the pulp molding process, a large plate with multiple pulp trays is usually formed in batches, and then cut into individual pulp trays, which in turn improves production efficiency and reduces production costs.

[0026] The molding process usually involves pulp preparation, molding mold making, dehydration and qualitative steps.

[0027] Pulp preparation: Pulp is usually made from waste paper or other plant fibers through processes such as crushing and beating. In this process, it is necessary to control parameters such as pulp concentration, fiber length and dispersion to ensure the quality of the forming.

[0028] Forming mold: The forming mold is the core component in the forming process. Its design determines the shape, size and precision of the pulp tray. The mold usually adopts a porous structure to facilitate the deposition and filtration and dehydration of the fibers in the pulp on the mold.

[0029] Dehydration and shaping: During the shaping process, the water in the pulp is discharged through the pores of the mold, and the fibers form a compact structure on the mold. This process requires controlling the dehydration speed and shaping pressure to ensure the strength and shape stability of the pulp support.

[0030] In the present application, for the specific process of the process of forming a pulp support plate having a plurality of pulp supports spaced apart by pulp molding, please refer to the prior art, and the present application will not elaborate on it.

[0031] S2: Glue brushing: brushing a glue layer for bonding paper cards on the pulp tray;

[0032] In the traditional process, the pulp pallet is usually trimmed to form a single pulp pallet, and then the worker brushes glue on the pulp pallet and sticks the paper card. However, considering that there are many product gluing rows, if each product is trimmed and then glued, it will take a lot of time to pick up and put, which is inconvenient for employees to operate. Therefore, the gluing process is swapped with the trimming process to improve the overall efficiency.

[0033] In the present application, a glue layer for bonding paper cards is brushed on the pulp support on the pulp support plate before trimming, which facilitates batch glue brushing and improves glue brushing efficiency and production efficiency.

[0034] It should be noted that glue application is a key step to evenly apply glue on the pulp tray, which directly affects the bonding effect between the pulp tray and the paper card. During the glue application process, it is necessary to ensure that the glue is evenly distributed on the pulp tray to avoid local glue shortage or glue accumulation. This can be achieved by adjusting the parameters of the glue application equipment, selecting the appropriate glue concentration, and controlling the coating speed.

[0035] In one of the embodiments, in the glue brushing step, a milky white water-based hot melt adhesive is used. For example, the ingredients of the water-based hot melt adhesive include: water-based urethane dispersion: 40%-42%, deionized water: 58%-60%, the pH value of the 1% aqueous solution of the water-based hot melt adhesive is 7-9, the initial boiling point of the water-based hot melt adhesive is 100°C, the secondary heating melting point is 120°C, and the dynamic viscosity is <250mPa.s. For example, in the glue brushing step, the position size of the glue-brushing screen printing screen is 30mm larger than the edge of the pulp pallet of the glue-brushing product and less than 50mm. For example, the mesh number of the glue-brushing screen printing screen is selected from an 80-mold screen, the thickness of the glue-brushing screen printing screen is 0.3mm, and the thickness of the screen printing glue position is 0.2mm. For example, the thickness of the glue layer formed after the water-based hot melt adhesive is completely dried is controlled between 0.10-0.15mm.

[0036] In order to improve the effect of brushing glue and improve product quality, the applicant has studied the brushing glue. For example, the glue is an environmentally friendly water-based hot melt glue that is milky white.

[0037] Ingredients: aqueous urethane dispersion (40%-42%), deionized water (58%-60%).

[0038] pH value: (1% aqueous solution) is 7-9.

[0039] The first boiling point is 100℃, and the second heating melting point is 120℃.

[0040] Dynamic viscosity: <250mPa.s.

[0041] In this way, the use of the above water-based hot melt adhesive can better ensure the bonding strength between the paper card and the pulp tray, and during the glue application process, it can ensure that the glue application process is smooth and it is not easy to leak and contaminate the product.

[0042] In order to further control the quality of glue application, for example, the following process is used to control the amount of glue application. The position size of the screen is 30mm larger than the edge of the glue-applied product and smaller than 50mm. If the edge is too small, the glue reflow time is too short, and the glue will drip onto the product through the mesh, resulting in product defects. If the edge is larger than 50mm, glue is wasted and glue costs are increased.

[0043] After repeated tests and verifications, the thickness of the glue layer formed after the glue is completely dried is controlled between 0.10-0.15mm. The secondary heating of paper and plastic to bond the cardboard will not waste glue, and at the same time, the cardboard can be firmly adhered. The mesh number uses an 80-mode screen, the screen printing screen thickness is 0.3mm, the screen printing glue position thickness is 0.2mm, the glue brushing thickness is just controlled between 0.08-0.15mm, and the thickness of the glue after drying is between 0.05-0.12mm, which meets the glue quantity control requirements.

[0044] In one embodiment, after applying the glue, the glue layer on the pulp pallet is dried, and the drying method is natural drying or heating drying. For example, heating drying uses a drying line, the heating section of the drying line shall not be less than 5 meters, the drying temperature of the heating section is 80 degrees Celsius, and the drying line speed is: 5m / min. For example, in natural drying, the air humidity is 40%-80%, the temperature is 15℃-30℃, and the drying time is 12-18 hours. In this embodiment, an environmentally friendly water-based hot melt adhesive is selected in combination with the glue, so two drying methods can be selected. The first is natural drying, which is suitable for a mode with a relatively sufficient delivery period and a relatively spacious site. The air humidity is 40%-80%, the temperature is 15℃-30℃, and the drying time is 12-18 hours. The second is heating drying, which is suitable for a mode with a short delivery period and a relatively narrow production area. Heating drying requires the use of a drying line. The length of the drying line shall not be less than 9 meters, the intermediate heating section shall not be less than 5 meters, the drying temperature is controlled at 80℃, and the drying line speed is: 5m / min. In this way, since the present application adopts the above-mentioned water-based hot melt adhesive, an appropriate drying method can be selected according to the length of the construction period. Of course, the cost of natural drying is lower than that of heating drying, and the cost of heating drying is shorter than the time of natural drying.

[0045] S3: trimming: trimming the pulp support plate to form a plurality of pulp supports;

[0046] Edge trimming is the step of cutting the pulp pallet into multiple independent pulp pallets, which is crucial to the dimensional accuracy and appearance quality of the product. The specific process of the edge trimming process will not be described in detail in this application, and please refer to the prior art.

[0047] S4: Placing the paper card: aligning the paper card and placing it on the glue layer of the pulp tray;

[0048] By aligning the paper card and placing it on the glue layer of the pulp tray, it is convenient to bond the paper card and the pulp tray later.

[0049] S5: Machine bonding: Adhesive equipment is used to heat and pressurize to melt the glue layer, so that the paper card and the pulp tray are bonded together.

[0050] By using a bonding device to heat and pressurize the pulp tray and the paper card, the glue layer is melted and bonded together, thereby ensuring that the paper card and the pulp tray are bonded together. For example, the pressure applied is 400N, so that the pulp tray and the paper card are bonded together. Specifically, the pulp product is placed in a jig on a high-frequency table, the product is placed, the jig is heated, and a 400N is applied to the paper card, so that the pulp tray and the paper card are bonded together.

[0051] The above-mentioned method of gluing and bonding pulp molded products takes into account that the number of product gluing rows is relatively large. If each product is glued after trimming, it will be time-consuming to pick up and put down, which is inconvenient for employees to operate. Therefore, the gluing process is swapped with the trimming process, and glue is applied before the trimming process. This reduces the time for subsequent workers to pick up and put down a single pulp tray, improves the overall efficiency, and can simply and quickly glue the paper card and the pulp tray together. The production process is highly efficient and can reduce the packaging cost of pulp molded products.

[0052] The paper pulp molded product gluing method of the present application is adopted. Under the lighting conditions of 900~1100Lux, the inspection distance is 30±2cm, the angle is ±30°, and the inspection time is 8~10s. Visually inspect whether the paper support and the paper card are bonded together; if more than 22mm are not bonded together, it is judged as unqualified. If it is not more than 22mm, tear the position of the paper pulp support and the paper card apart. If the paper pulp support is bonded, it is judged as qualified. It was found through inspection that the qualified rate was 100% due to the adoption of the paper pulp molded product gluing method of the present application, and the process efficiency was extremely high.

[0053] It is particularly important to explain that, by using the glue-brushing method for pulp molded products of the present application, glue can be brushed on the pulp tray in advance and dried before trimming. Then, the paper tray can be delivered to the user, and when the user uses it, the paper card and the pulp tray can be directly bonded together with the bonding device, which is extremely convenient for the user and improves the convenience of use.

[0054] Moreover, the glue brushing bonding method for pulp molding products of the present application, combined with the glue brushing method and drying method of the present application, not only improves the convenience of use for users, but also has better bonding strength.

[0055] The present application also provides a pulp molded product, which is formed by bonding a pulp support plate and a paper card using the glue bonding method for pulp molded products as described in any of the above embodiments.

[0056] It should be noted that the present invention mainly relates to a packaging process, which aims to bond paper and pulp tray together in a simple and quick way.

[0057] 1. Design ideas.

[0058] Brush glue on paper-plastic products → dry → package products → place paper cards → machine glue → pack.

[0059] 2. Glue performance.

[0060] The glue is environmentally friendly water-based hot melt adhesive, which is milky white.

[0061] Ingredients: aqueous urethane dispersion (40%-42%), deionized water (58%-60%).

[0062] pH value: (1% aqueous solution) is 7-9.

[0063] The first boiling point is 100℃, and the second heating melting point is 120℃.

[0064] Dynamic viscosity: <250mPa.s.

[0065] 3. Control the amount of glue applied.

[0066] The position size of the screen is 30mm larger than the edge of the glue-brushing product and smaller than 50mm. If the edge is too small, the glue reflow time is too short, and the glue will drip through the mesh onto the product, resulting in product defects. If the edge is larger than 50mm, glue will be wasted and glue costs will increase.

[0067] After repeated tests and verifications, the thickness of the glue after drying is controlled between 0.10-0.15mm. The secondary heating of paper and plastic to bond the cardboard will not waste glue, and at the same time, the cardboard can be firmly bonded. The mesh size is 80, the screen printing screen thickness is 0.3mm, the screen printing glue position thickness is 0.2mm, the glue brushing thickness is just controlled between 0.08-0.15mm, and the glue after drying is between 0.05-0.12mm, which meets the glue quantity control requirements.

[0068] 4. Row module.

[0069] Based on the size of the machine's operating plane, combined with the product size and the overall mold count, we can increase production capacity and reduce costs.

[0070] 5. Adjust the process sequence.

[0071] Considering that there are many product gluing modules, if each product is trimmed before gluing, it will be time-consuming and inconvenient for employees to operate. Therefore, the gluing process and the trimming process are swapped to improve overall efficiency.

[0072] 6. Choose drying method.

[0073] Because the glue we choose is quick-drying glue, there are two drying methods. The first is natural drying, which is suitable for models with ample delivery time and spacious sites. The air humidity is 40%-80%, the temperature is 15℃-30℃, and the drying time is 12-18 hours. The second is heating and drying, which is suitable for models with short delivery time and narrow production areas. Heating and drying requires the use of a drying line. The length of the drying line shall not be less than 9 meters, the middle heating section shall not be less than 5 meters, the drying temperature shall be controlled at 80℃, and the drying line speed is: 5m / min.

[0074] 7. Product packaging method: The pulp product is placed in a jig on a high-frequency table. The product is placed in the jig, the jig is heated up, and a 400N force is applied to the paper card to make the pulp tray and the paper card bonded together.

[0075] 8. Inspection standard: Under the lighting condition of 900~1100Lux, inspection distance is 30±2cm, angle is ±30℃, inspection time is 8~10s, visually inspect whether the paper tray is bonded to the paper card; if there is more than 22mm of non-bonding, it is judged as unqualified; if there is less than 22mm of non-bonding, tear open the paper tray and paper card, if the paper tray is bonded, it is judged as qualified.

[0076] The technical features of the above-described embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. It should be noted that "in one embodiment", "for example", "for example", etc. in this application are intended to illustrate the present application, rather than to limit the present application. The above-described embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as a limitation on the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, several variations and improvements can be made, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A method for gluing pulp molded products, characterized in that: The steps include: Forming: forming a pulp support plate with a plurality of pulp supports spaced apart; Glue brushing: brush a glue layer for bonding paper cards on the pulp tray; Trimming: trimming the pulp tray to form multiple pulp trays; Place the paper card: align the paper card and place it on the glue layer of the pulp tray; Machine bonding: Use bonding equipment to heat and apply pressure to melt the glue layer, so that the paper card and the pulp tray are bonded together.

2. The method for gluing pulp molded products according to claim 1, characterized in that: In the glue-brushing step, a milky white water-based hot melt adhesive is used.

3. The method for gluing pulp molded products according to claim 2, characterized in that: The components of the water-based hot melt adhesive include: water-based urethane dispersion: 40%-42%, deionized water: 58%-60%, the pH value of a 1% aqueous solution of the water-based hot melt adhesive is 7-9, the initial boiling point of the water-based hot melt adhesive is 100°C, the secondary heating melting point is 120°C, and the dynamic viscosity is: <250mPa.s.

4. The method for gluing pulp molded products according to claim 3, characterized in that: In the glue-brushing step, the position size of the glue-brushing silk-screen screen is 30 mm larger than the edge of the pulp support plate of the glue-brushing product and smaller than 50 mm.

5. The method for gluing pulp molded products according to claim 4, characterized in that: The mesh count of the glue-brushed silk-screen printing screen is 80-mode, the thickness of the glue-brushed silk-screen printing screen is 0.3mm, and the thickness of the silk-screen glue position is 0.2mm.

6. The method for gluing pulp molded products according to claim 5, characterized in that: The thickness of the glue layer formed after the water-based hot melt adhesive is dried is controlled between 0.10-0.15mm.

7. The method for gluing pulp molded products according to claim 6, characterized in that: After applying the glue, the glue layer on the pulp pallet is dried by natural drying or heating drying.

8. The method for gluing pulp molded products according to claim 7, characterized in that: The drying process is carried out using a drying line. The heating section of the drying line must not be less than 5 meters. The drying temperature of the heating section is 80 degrees Celsius and the drying line speed is 5m / min.

9. The method for gluing pulp molded products according to claim 7, characterized in that: During natural drying, the air humidity is 40%-80%, the temperature is 15℃-30℃, and the drying time is 12-18 hours.

10. A pulp molded product, characterized in that: The pulp molded product is formed by bonding a pulp pallet and a paper card using the glue bonding method for pulp molded products as described in any one of claims 1 to 9.

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