Tough type washed kraft paper hook and preparation method thereof

Abstract

The invention discloses a tough type washed kraft paper hook and a preparation method thereof. The tough type washed kraft paper hook comprises two hook plates extending out of the top of a packaging box and two connecting plates fixedly attached to the inner wall of the top of the packaging box. The two hook plates are symmetrical to each other and are integrally formed and connected, the two hook plates are arranged in a mutually foldable mode, hook holes are formed in the two hook plates, the two hook plates are bonded and fixed through a first adhesive layer after being folded, the two hook holes are communicated with each other in an opposite mode, and each hook plate comprises a first outer layer and a first inner layer; the two connecting plates are symmetrical to each other and are integrally formed and connected with the outer ends of the two hook plates respectively, and the two connecting plates can be bent relative to the two hook plates respectively. The pothook is manufactured by adopting the water-washed kraft paper according to the formula and adopting the structure and the preparation method, the pothook has very high toughness, the bearing capacity is effectively improved, multiple layers of paper do not need to be mounted, the loss of manufacturing materials is small, the manufacturing efficiency is high, and convenience is brought to production operation.

Description

Technical Field

[0001] The invention relates to the field of packaging box accessories, in particular to a strong and tough washed kraft paper hook and a preparation method thereof. Background Art

[0002] A box hook is a device designed on a box for hanging or fixing items. This hook can be easily integrated into various boxes, such as gift boxes, express boxes, storage boxes, etc., to provide users with additional convenience when carrying, storing or displaying items. Adding hooks to gift boxes makes it convenient for users to hang gifts on door handles, tree branches or other fixed points to increase the display effect of gifts. The hooks on express boxes can be used to hang shopping bags, small items, etc., making it convenient for users to organize and carry. Setting hooks on storage boxes can hang items such as clothing, hats, scarves, etc., saving space and improving storage efficiency. The hooks on display boxes can be used to hang small accessories, key chains and other items to increase the attractiveness and visibility of the product.

[0003] In order to ensure the load-bearing capacity of the hook, the hooks in the past were generally plastic hooks. Based on environmental protection requirements, paper hooks are commonly used to replace plastic hooks in the market. However, the load-bearing capacity of paper hooks is closely related to the thickness of the paper. If you want to have a strong strength, you need to mount multiple layers of paper. This method not only has a large loss, but also has low production efficiency. Therefore, it is necessary to study a solution to solve the above problems. Summary of the invention

[0004] In view of this, the present invention aims at the deficiencies in the prior art, and its main purpose is to provide a strong washed kraft paper hook and a preparation method thereof, which can effectively solve the problems of large loss and low efficiency in the production of existing paper hooks.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A strong and tough washed kraft paper hook, comprising two hook plates extending outward from the top of a packaging box and two connecting plates fixedly attached to the inner wall of the top of the packaging box;

[0007] The two hook plates are symmetrical and integrally connected to each other, and the two hook plates are foldably arranged to each other. Both hook plates are provided with hook holes. After folding, the two hook plates are bonded and fixed by the first adhesive layer, and the two hook holes are directly connected to each other. Each hook plate includes a first outer layer and a first inner layer, the first outer layer is made of washed kraft paper, the first inner layer is inlaid and fixed in the first outer layer, and the first inner layer is made of carbon fiber material;

[0008] The two connecting plates are symmetrical to each other and are integrally connected with the outer ends of the two hook plates respectively. The two connecting plates are bendably arranged relative to the two hook plates respectively. A second adhesive layer is arranged on the surface of each connecting plate. Each connecting plate includes a second outer layer and a second inner layer. The second outer layer is made of washed kraft paper. The second outer layer is integrally connected with the first outer layer. The second inner layer is inlaid and fixed in the second outer layer. The second inner layer is made of carbon fiber. The second inner layer is separated from the first inner layer.

[0009] The washed kraft paper material includes the following raw materials in parts by weight:

[0010] 55-70 parts of long fiber wood pulp; 35-45 parts of short fiber wood pulp; 15-18 parts of synthetic fiber; 20-25 parts of cotton pulp; 4-5 parts of wet strength agent; 2-3 parts of water repellent; 0.8-1.2 parts of dispersant; 25-30 parts of filler.

[0011] As a preferred solution, the long-fiber wood pulp is coniferous wood pulp, the short-fiber wood pulp is broadleaf wood pulp, and the synthetic fiber is aramid fiber or polyvinyl alcohol fiber.

[0012] As a preferred embodiment, the wet strength agent is polyamide polyamine epichlorohydrin.

[0013] As a preferred embodiment, the water repellent is an alkyl ketene dimer.

[0014] As a preferred solution, the dispersant is sodium polyacrylate.

[0015] As a preferred solution, the filler is calcium carbonate.

[0016] As a preferred solution, the inner sides of the two hook plates are coated with a first adhesive layer, and after folding, the two first adhesive layers are bonded and fixed together.

[0017] As a preferred solution, the width of the connecting plate is greater than the width of the hook plate, and the inner middle portion of the connecting plate is integrally connected with the outer end of the hook plate to form a T-shaped structure.

[0018] A method for preparing a strong washed kraft paper hook comprises the following steps:

[0019] (1) beating: long fiber pulp, short fiber pulp and cotton pulp are respectively put into respective beating equipment for beating treatment, the beating degree of long fiber pulp is controlled at 30-40°SR, and the beating degree of short fiber pulp is controlled at 40-50°SR; and the synthetic fiber is separately opened to make it fully dispersed, and then mixed evenly with the beaten long fiber pulp, short fiber pulp and cotton pulp according to a proportion;

[0020] (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in sequence, and continue stirring for 30-60 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension;

[0021] (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, a plurality of uncured carbon fiber cloths that have been cut are placed. Then, the papermaking machine's forming device is used to perform preliminary dehydration and forming to form a wet paper sheet. Then, the wet paper sheet is passed through a pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa.

[0022] (4) Drying: After being pressed, the paper sheet enters the drying section and is dried by steam heating or hot air drying. The drying temperature is controlled at 125-140°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer and the second inner layer.

[0023] (5) Post-treatment: The dried paper is calendered as needed, and the calendering pressure is controlled at 10-20 MPa;

[0024] (6) Cutting: Cutting the paper to form two hook plates and two connecting plates connected in one piece;

[0025] (7) Gluing: applying glue on corresponding positions of the two hook plates and the two connecting plates to form a first glue layer and a second glue layer;

[0026] (8) Folding and forming: fold the two hook plates and fix them together through the first adhesive layer, and make the two connecting plates bend relative to the two hook plates respectively, the two connecting plates extend horizontally, and the two hook plates extend vertically.

[0027] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical solution that:

[0028] By adopting the washed kraft paper material of the formula of the present invention and cooperating with the structure and preparation method of the present invention to produce a hook, the hook has strong toughness and its load-bearing capacity is effectively improved. There is no need to mount multiple layers of paper, the material loss is small, and the production efficiency is high, which brings convenience to production operations.

[0029] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a three-dimensional diagram of a preferred embodiment of the present invention before being folded;

[0031] Figure 2 It is a three-dimensional diagram of another angle of the preferred embodiment of the present invention before being folded;

[0032] Figure 3 It is a three-dimensional diagram of the folding process of the preferred embodiment of the present invention;

[0033] Figure 4 This is a three-dimensional diagram of a preferred embodiment of the present invention after folding;

[0034] Figure 5 It is a cross-sectional view of a preferred embodiment of the present invention after folding.

[0035] Description of the accompanying drawings:

[0036] 10. Hook plate 11. First outer layer

[0037] 12. First inner layer 101, hook hole

[0038] 20. Connecting plate 21. Second outer layer

[0039] 22. Second inner layer 31. First adhesive layer

[0040] 32. Second adhesive layer. DETAILED DESCRIPTION

[0041] Please refer to Figures 1 to 5 As shown, it shows the specific structure of a strong washed kraft paper hook of a preferred embodiment of the present invention, including two hook plates 10 extending outward from the top of the packaging box and two connecting plates 20 fixedly attached to the top inner wall of the packaging box.

[0042] The two hook plates 10 are symmetrical and integrally connected, and the two hook plates 10 are foldable. The two hook plates 10 are provided with hook holes 101, which are isosceles triangles. After folding, the two hook plates 10 are bonded and fixed by the first adhesive layer 31, and the two hook holes 31 are connected to each other. Each hook plate 10 includes a first outer layer 11 and a first inner layer 12. The first outer layer 11 is made of washed kraft paper. The first inner layer 12 is fixed in the first outer layer 11 by inlay molding. The first inner layer 12 is made of carbon fiber. The first inner layer 12 is used to improve the structural strength and play a good supporting role. The inner side surfaces of the two hook plates 10 are coated with the first adhesive layer 31. After folding, the two first adhesive layers 31 are bonded and fixed to each other.

[0043] The two connecting plates 20 are symmetrical to each other and are integrally connected with the outer ends of the two hook plates 10, respectively. The two connecting plates 20 are respectively arranged relative to the two hook plates 10 so as to be bendable to each other. A second adhesive layer 32 is arranged on the surface of each connecting plate 20. Each connecting plate 20 includes a second outer layer 21 and a second inner layer 22. The second outer layer 21 is made of washed kraft paper. The second outer layer 21 is integrally connected with the first outer layer 11. The second inner layer 22 is inlaid and fixed in the second outer layer 21. The second inner layer 22 is made of carbon fiber. The second inner layer 22 is used to improve the structural strength and play a good supporting role. The second inner layer 22 is separated from the first inner layer 12. The width of the connecting plate 20 is greater than the width of the hook plate 10. The inner middle part of the connecting plate 20 is integrally connected with the outer end of the hook plate 10 to form a T-shaped structure.

[0044] The washed kraft paper material includes the following raw materials in parts by weight:

[0045] 55-70 parts of long fiber pulp; 35-45 parts of short fiber pulp; 15-18 parts of synthetic fiber; 20-25 parts of cotton pulp; 4-5 parts of wet strength agent; 2-3 parts of water repellent; 0.8-1.2 parts of dispersant; 25-30 parts of filler. The long fiber pulp is coniferous pulp, which can provide the basic strength and toughness skeleton of the paper. Its fiber length is long and has strong interweaving ability, which can enhance the tensile resistance of the paper; the short fiber pulp is broadleaf pulp, which can fill the gaps between the long fibers, making the paper structure more compact, and at the same time helps to improve the uniformity and smoothness of the paper, and also helps to improve the overall strength of the paper; the synthetic fiber is aramid fiber or polyvinyl alcohol fiber, which has the characteristics of high strength and high modulus, can significantly improve the toughness of washed kraft paper, especially the strength retention in wet state, and enhance the ability of paper to resist external force damage. The cotton pulp can improve the strength of paper. The cotton pulp fibers are relatively long. After interweaving, the tensile strength of the paper can be enhanced, making the kraft paper tougher and less likely to tear. It can better withstand pressure and tension in packaging and other usage scenarios. At the same time, the cotton pulp can improve the smoothness of the paper, making the surface of the paper smoother and more sleek, which is conducive to subsequent printing and other processing. In addition, the cotton pulp helps to improve the durability of the kraft paper, allowing the paper to resist the adverse effects of time and environmental factors and extend its service life. The wet strength agent is polyamide polyamine epichlorohydrin, which can form a covalent bond with the fiber. When the paper encounters water, it can effectively prevent the destruction of hydrogen bonds between the fibers, thereby improving the wet strength of the paper and ensuring that the paper is not easily deformed or damaged during the washing process. The water repellent is an alkyl ketene dimer, which can form a hydrophobic film on the fiber surface, reduce the water absorption of the paper, minimize the absorption of water during the washing process, and maintain the dimensional stability and strength of the paper. The dispersant is sodium polyacrylate, which is used to evenly disperse the fibers and additives, prevent fiber agglomeration, ensure the uniformity of paper quality, and help improve the comprehensive performance of the paper. The filler is calcium carbonate, which can improve the opacity, whiteness and printability of paper, and at the same time improve the stiffness of paper to a certain extent. However, adding too much may affect the strength of the paper and needs to be reasonably controlled.

[0046] The present invention also discloses a method for preparing the aforementioned strong and tough washed kraft paper hook, comprising the following steps:

[0047] (1) Pulping: Long-fiber wood pulp, short-fiber wood pulp and cotton pulp are respectively put into respective pulping equipment for pulping. The beating degree of long-fiber wood pulp is controlled at 30-40°SR, and the beating degree of short-fiber wood pulp is controlled at 40-50°SR, so that the fibers have an appropriate degree of fibrillation and improve the bonding force between the fibers. The synthetic fibers are separately opened to make them fully dispersed, and then mixed evenly with the beaten long-fiber wood pulp, short-fiber wood pulp and cotton pulp according to the proportion.

[0048] (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in turn, and continue stirring for 30-60 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension.

[0049] (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, multiple pieces of uncured carbon fiber cloth that have been cut are placed, and then the forming device of the paper machine is used to perform preliminary dehydration and forming to form wet paper sheets. Then, the wet paper sheets are passed through the pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa, and the pressing time is adjusted according to the paper weight and equipment performance.

[0050] (4) Drying: After being pressed, the paper sheets enter the drying section and are dried by steam heating or hot air drying. The drying temperature is controlled at 125-140°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer 12 and the second inner layer 22. During the drying process, attention should be paid to the uniformity of temperature to avoid deformation or strength loss of the paper due to excessive local drying.

[0051] (5) Post-treatment: The dried paper is calendered as needed, and the calendering pressure is controlled at 10-20 MPa.

[0052] (6) Cutting: Figure 1 As shown, paper is cut to form two hook plates 10 and two connecting plates 20 that are integrally connected.

[0053] (7) Gluing: Glue is applied to corresponding positions on the two hook plates 10 and the two connecting plates 20 to form a first adhesive layer 31 and a second adhesive layer 32 .

[0054] (8) Folding and forming: Fold the two hook plates 10 and fix them together through the first adhesive layer 31 (such as Figure 3 ), and the two connecting plates 20 are bent relative to the two hook plates 10, the two connecting plates 20 extend horizontally, and the two hook plates 10 extend vertically (such as Figure 4 ).

[0055] When in use, the two hook plates 10 are extended outward from the bottom to the top through the slots on the top of the packaging box, and the second adhesive layers 32 on the two connecting plates 20 are bonded and fixed to the inner wall of the top of the packaging box.

[0056] The present invention is further described in detail with multiple embodiments below:

[0057] Embodiment 1:

[0058] A strong and tough washed kraft paper hook comprises two hook plates 10 extending outward from the top of a packaging box and two connecting plates 20 fixedly attached to the inner wall of the top of the packaging box.

[0059] The two hook plates 10 are symmetrical and integrally connected, and the two hook plates 10 are foldable. The two hook plates 10 are provided with hook holes 101, which are isosceles triangles. After folding, the two hook plates 10 are bonded and fixed by the first adhesive layer 31, and the two hook holes 31 are connected to each other. Each hook plate 10 includes a first outer layer 11 and a first inner layer 12. The first outer layer 11 is made of washed kraft paper. The first inner layer 12 is fixed in the first outer layer 11 by inlay molding. The first inner layer 12 is made of carbon fiber. The first inner layer 12 is used to improve the structural strength and play a good supporting role. The inner side surfaces of the two hook plates 10 are coated with the first adhesive layer 31. After folding, the two first adhesive layers 31 are bonded and fixed to each other.

[0060] The two connecting plates 20 are symmetrical to each other and are integrally connected with the outer ends of the two hook plates 10, respectively. The two connecting plates 20 are respectively arranged relative to the two hook plates 10 so as to be bendable to each other. A second adhesive layer 32 is arranged on the surface of each connecting plate 20. Each connecting plate 20 includes a second outer layer 21 and a second inner layer 22. The second outer layer 21 is made of washed kraft paper. The second outer layer 21 is integrally connected with the first outer layer 11. The second inner layer 22 is inlaid and fixed in the second outer layer 21. The second inner layer 22 is made of carbon fiber. The second inner layer 22 is used to improve the structural strength and play a good supporting role. The second inner layer 22 is separated from the first inner layer 12. The width of the connecting plate 20 is greater than the width of the hook plate 10. The inner middle part of the connecting plate 20 is integrally connected with the outer end of the hook plate 10 to form a T-shaped structure.

[0061] The washed kraft paper material includes the following raw materials in parts by weight:

[0062] 55 parts of long fiber pulp; 45 parts of short fiber pulp; 16 parts of synthetic fiber; 23 parts of cotton pulp; 4.5 parts of wet strength agent; 2 parts of water repellent; 0.9 parts of dispersant; 27 parts of filler. The long fiber pulp is coniferous pulp, which can provide the basic strength and toughness skeleton of the paper. Its fiber length is long and has strong interweaving ability, which can enhance the tensile resistance of the paper; the short fiber pulp is broadleaf pulp, which can fill the gaps between the long fibers, making the paper structure more compact, and at the same time helps to improve the uniformity and smoothness of the paper, and also helps to improve the overall strength of the paper; the synthetic fiber is aramid fiber, which has the characteristics of high strength and high modulus, can significantly improve the toughness of washed kraft paper, especially the strength retention in wet state, and enhance the ability of paper to resist external force damage. The cotton pulp can improve the strength of paper. The cotton pulp fibers are relatively long. After interweaving, the tensile strength of the paper can be enhanced, making the kraft paper tougher and less likely to tear. It can better withstand pressure and tension in packaging and other usage scenarios. At the same time, the cotton pulp can improve the smoothness of the paper, making the surface of the paper smoother and more sleek, which is conducive to subsequent printing and other processing. In addition, the cotton pulp helps to improve the durability of the kraft paper, allowing the paper to resist the adverse effects of time and environmental factors and extend its service life. The wet strength agent is polyamide polyamine epichlorohydrin, which can form a covalent bond with the fiber. When the paper encounters water, it can effectively prevent the destruction of hydrogen bonds between the fibers, thereby improving the wet strength of the paper and ensuring that the paper is not easily deformed or damaged during the washing process. The water repellent is an alkyl ketene dimer, which can form a hydrophobic film on the fiber surface, reduce the water absorption of the paper, minimize the absorption of water during the washing process, and maintain the dimensional stability and strength of the paper. The dispersant is sodium polyacrylate, which is used to evenly disperse the fibers and additives, prevent fiber agglomeration, ensure the uniformity of paper quality, and help improve the comprehensive performance of the paper. The filler is calcium carbonate, which can improve the opacity, whiteness and printability of paper, and at the same time improve the stiffness of paper to a certain extent. However, adding too much may affect the strength of the paper and needs to be reasonably controlled.

[0063] This embodiment also discloses a method for preparing the aforementioned strong washed kraft paper hook, comprising the following steps:

[0064] (1) Pulping: Long-fiber wood pulp, short-fiber wood pulp and cotton pulp are respectively put into respective pulping equipment for pulping. The beating degree of long-fiber wood pulp is controlled at 35°SR and that of short-fiber wood pulp is controlled at 45°SR, so that the fibers have an appropriate degree of fibrillation and improve the bonding force between the fibers. The synthetic fibers are separately opened to be fully dispersed, and then evenly mixed with the beaten long-fiber wood pulp, short-fiber wood pulp and cotton pulp according to a certain proportion.

[0065] (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in turn, and continue stirring for 50 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension.

[0066] (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, multiple pieces of uncured carbon fiber cloth that have been cut are placed, and then the forming device of the paper machine is used to perform preliminary dehydration and forming to form wet paper sheets. Then, the wet paper sheets are passed through the pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa, and the pressing time is adjusted according to the paper weight and equipment performance.

[0067] (4) Drying: After being pressed, the paper sheets enter the drying section and are dried by steam heating or hot air drying. The drying temperature is controlled at 130°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer 12 and the second inner layer 22. During the drying process, attention should be paid to the uniformity of temperature to avoid deformation or strength loss of the paper due to excessive local drying.

[0068] (5) Post-processing: The dried paper is calendered as needed, and the calendering pressure is controlled at 15 MPa.

[0069] (6) Cutting: Figure 1 As shown, paper is cut to form two hook plates 10 and two connecting plates 20 that are integrally connected.

[0070] (7) Gluing: Glue is applied to corresponding positions on the two hook plates 10 and the two connecting plates 20 to form a first adhesive layer 31 and a second adhesive layer 32 .

[0071] (8) Folding and forming: Fold the two hook plates 10 and fix them together through the first adhesive layer 31 (such as Figure 3 ), and the two connecting plates 20 are bent relative to the two hook plates 10, the two connecting plates 20 extend horizontally, and the two hook plates 10 extend vertically (such as Figure 4 ).

[0072] When in use, the two hook plates 10 are extended outward from the bottom to the top through the slots on the top of the packaging box, and the second adhesive layers 32 on the two connecting plates 20 are bonded and fixed to the inner wall of the top of the packaging box.

[0073] Through use tests, it was found that the hook in this embodiment, which has the same thickness as ordinary paper, has a tensile strength of 1200 grams of tension per centimeter of width and is not easily torn.

[0074] Embodiment 2:

[0075] A strong and tough washed kraft paper hook comprises two hook plates 10 extending outward from the top of a packaging box and two connecting plates 20 fixedly attached to the inner wall of the top of the packaging box.

[0076] The two hook plates 10 are symmetrical and integrally connected, and the two hook plates 10 are foldable. The two hook plates 10 are provided with hook holes 101, which are isosceles triangles. After folding, the two hook plates 10 are bonded and fixed by the first adhesive layer 31, and the two hook holes 31 are connected to each other. Each hook plate 10 includes a first outer layer 11 and a first inner layer 12. The first outer layer 11 is made of washed kraft paper. The first inner layer 12 is fixed in the first outer layer 11 by inlay molding. The first inner layer 12 is made of carbon fiber. The first inner layer 12 is used to improve the structural strength and play a good supporting role. The inner side surfaces of the two hook plates 10 are coated with the first adhesive layer 31. After folding, the two first adhesive layers 31 are bonded and fixed to each other.

[0077] The two connecting plates 20 are symmetrical to each other and are integrally connected with the outer ends of the two hook plates 10, respectively. The two connecting plates 20 are respectively arranged relative to the two hook plates 10 so as to be bendable to each other. A second adhesive layer 32 is arranged on the surface of each connecting plate 20. Each connecting plate 20 includes a second outer layer 21 and a second inner layer 22. The second outer layer 21 is made of washed kraft paper. The second outer layer 21 is integrally connected with the first outer layer 11. The second inner layer 22 is inlaid and fixed in the second outer layer 21. The second inner layer 22 is made of carbon fiber. The second inner layer 22 is used to improve the structural strength and play a good supporting role. The second inner layer 22 is separated from the first inner layer 12. The width of the connecting plate 20 is greater than the width of the hook plate 10. The inner middle part of the connecting plate 20 is integrally connected with the outer end of the hook plate 10 to form a T-shaped structure.

[0078] The washed kraft paper material includes the following raw materials in parts by weight:

[0079] 70 parts of long fiber pulp; 35 parts of short fiber pulp; 15 parts of synthetic fiber; 25 parts of cotton pulp; 4 parts of wet strength agent; 2.5 parts of water repellent; 0.8 parts of dispersant; 2.5 parts of filler. The long fiber pulp is coniferous pulp, which can provide the basic strength and toughness skeleton of the paper. Its fiber length is long and has strong interweaving ability, which can enhance the tensile resistance of the paper; the short fiber pulp is broadleaf pulp, which can fill the gaps between the long fibers, making the paper structure more compact, and at the same time helps to improve the uniformity and smoothness of the paper, and also helps to improve the overall strength of the paper; the synthetic fiber is polyvinyl alcohol fiber, which has the characteristics of high strength and high modulus, can significantly improve the toughness of washed kraft paper, especially the strength retention in wet state, and enhance the ability of paper to resist external damage. The cotton pulp can improve the strength of paper. The cotton pulp fibers are relatively long. After interweaving, the tensile strength of the paper can be enhanced, making the kraft paper tougher and less likely to tear. It can better withstand pressure and tension in packaging and other usage scenarios. At the same time, the cotton pulp can improve the smoothness of the paper, making the surface of the paper smoother and more sleek, which is conducive to subsequent printing and other processing. In addition, the cotton pulp helps to improve the durability of the kraft paper, allowing the paper to resist the adverse effects of time and environmental factors and extend its service life. The wet strength agent is polyamide polyamine epichlorohydrin, which can form a covalent bond with the fiber. When the paper encounters water, it can effectively prevent the destruction of hydrogen bonds between the fibers, thereby improving the wet strength of the paper and ensuring that the paper is not easily deformed or damaged during the washing process. The water repellent is an alkyl ketene dimer, which can form a hydrophobic film on the fiber surface, reduce the water absorption of the paper, minimize the absorption of water during the washing process, and maintain the dimensional stability and strength of the paper. The dispersant is sodium polyacrylate, which is used to evenly disperse the fibers and additives, prevent fiber agglomeration, ensure the uniformity of paper quality, and help improve the comprehensive performance of the paper. The filler is calcium carbonate, which can improve the opacity, whiteness and printability of paper, and at the same time improve the stiffness of paper to a certain extent. However, adding too much may affect the strength of the paper and needs to be reasonably controlled.

[0080] This embodiment also discloses a method for preparing the aforementioned strong washed kraft paper hook, comprising the following steps:

[0081] (1) Pulping: Long-fiber wood pulp, short-fiber wood pulp and cotton pulp are respectively put into respective pulping equipment for pulping. The beating degree of long-fiber wood pulp is controlled at 30°SR and that of short-fiber wood pulp is controlled at 40°SR, so that the fibers have an appropriate degree of fibrillation and the bonding force between the fibers is improved. The synthetic fibers are separately opened to be fully dispersed, and then evenly mixed with the beaten long-fiber wood pulp, short-fiber wood pulp and cotton pulp according to a certain proportion.

[0082] (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in turn, and continue stirring for 60 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension.

[0083] (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, multiple pieces of uncured carbon fiber cloth that have been cut are placed, and then the forming device of the paper machine is used to perform preliminary dehydration and forming to form wet paper sheets. Then, the wet paper sheets are passed through the pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa, and the pressing time is adjusted according to the paper weight and equipment performance.

[0084] (4) Drying: After being pressed, the paper sheets enter the drying section and are dried by steam heating or hot air drying. The drying temperature is controlled at 125°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer 12 and the second inner layer 22. During the drying process, attention should be paid to the uniformity of temperature to avoid deformation or strength loss of the paper due to excessive local drying.

[0085] (5) Post-treatment: The dried paper is calendered as needed, and the calendering pressure is controlled at 20 MPa.

[0086] (6) Cutting: Figure 1 As shown, paper is cut to form two hook plates 10 and two connecting plates 20 that are integrally connected.

[0087] (7) Gluing: Glue is applied to corresponding positions on the two hook plates 10 and the two connecting plates 20 to form a first adhesive layer 31 and a second adhesive layer 32 .

[0088] (8) Folding and forming: Fold the two hook plates 10 and fix them together through the first adhesive layer 31 (such as Figure 3 ), and the two connecting plates 20 are bent relative to the two hook plates 10, the two connecting plates 20 extend horizontally, and the two hook plates 10 extend vertically (such as Figure 4 ).

[0089] When in use, the two hook plates 10 are extended outward from the bottom to the top through the slots on the top of the packaging box, and the second adhesive layers 32 on the two connecting plates 20 are bonded and fixed to the inner wall of the top of the packaging box.

[0090] Through use tests, it was found that the hook in this embodiment, which has the same thickness as ordinary paper, has a tensile strength of 1250 grams of tension per centimeter width and is not easily torn.

[0091] Embodiment 3:

[0092] A strong and tough washed kraft paper hook comprises two hook plates 10 extending outward from the top of a packaging box and two connecting plates 20 fixedly attached to the inner wall of the top of the packaging box.

[0093] The two hook plates 10 are symmetrical and integrally connected, and the two hook plates 10 are foldable. The two hook plates 10 are provided with hook holes 101, which are isosceles triangles. After folding, the two hook plates 10 are bonded and fixed by the first adhesive layer 31, and the two hook holes 31 are connected to each other. Each hook plate 10 includes a first outer layer 11 and a first inner layer 12. The first outer layer 11 is made of washed kraft paper. The first inner layer 12 is fixed in the first outer layer 11 by inlay molding. The first inner layer 12 is made of carbon fiber. The first inner layer 12 is used to improve the structural strength and play a good supporting role. The inner side surfaces of the two hook plates 10 are coated with the first adhesive layer 31. After folding, the two first adhesive layers 31 are bonded and fixed to each other.

[0094] The two connecting plates 20 are symmetrical to each other and are integrally connected with the outer ends of the two hook plates 10, respectively. The two connecting plates 20 are respectively arranged relative to the two hook plates 10 so as to be bendable to each other. A second adhesive layer 32 is arranged on the surface of each connecting plate 20. Each connecting plate 20 includes a second outer layer 21 and a second inner layer 22. The second outer layer 21 is made of washed kraft paper. The second outer layer 21 is integrally connected with the first outer layer 11. The second inner layer 22 is inlaid and fixed in the second outer layer 21. The second inner layer 22 is made of carbon fiber. The second inner layer 22 is used to improve the structural strength and play a good supporting role. The second inner layer 22 is separated from the first inner layer 12. The width of the connecting plate 20 is greater than the width of the hook plate 10. The inner middle part of the connecting plate 20 is integrally connected with the outer end of the hook plate 10 to form a T-shaped structure.

[0095] The washed kraft paper material includes the following raw materials in parts by weight:

[0096] 65 parts of long fiber pulp; 40 parts of short fiber pulp; 18 parts of synthetic fiber; 20 parts of cotton pulp; 5 parts of wet strength agent; 3 parts of water repellent; 1.2 parts of dispersant; 30 parts of filler. The long fiber pulp is coniferous pulp, which can provide the basic strength and toughness skeleton of the paper. Its fiber length is long and has strong interweaving ability, which can enhance the tensile resistance of the paper; the short fiber pulp is broadleaf pulp, which can fill the gaps between the long fibers, making the paper structure more compact, and at the same time helps to improve the uniformity and smoothness of the paper, and also helps to improve the overall strength of the paper; the synthetic fiber is aramid fiber, which has the characteristics of high strength and high modulus, can significantly improve the toughness of washed kraft paper, especially the strength retention in wet state, and enhance the ability of paper to resist external force damage. The cotton pulp can improve the strength of paper. The cotton pulp fibers are relatively long. After interweaving, the tensile strength of the paper can be enhanced, making the kraft paper tougher and less likely to tear. It can better withstand pressure and tension in packaging and other usage scenarios. At the same time, the cotton pulp can improve the smoothness of the paper, making the surface of the paper smoother and more sleek, which is conducive to subsequent printing and other processing. In addition, the cotton pulp helps to improve the durability of the kraft paper, allowing the paper to resist the adverse effects of time and environmental factors and extend its service life. The wet strength agent is polyamide polyamine epichlorohydrin, which can form a covalent bond with the fiber. When the paper encounters water, it can effectively prevent the destruction of hydrogen bonds between the fibers, thereby improving the wet strength of the paper and ensuring that the paper is not easily deformed or damaged during the washing process. The water repellent is an alkyl ketene dimer, which can form a hydrophobic film on the fiber surface, reduce the water absorption of the paper, minimize the absorption of water during the washing process, and maintain the dimensional stability and strength of the paper. The dispersant is sodium polyacrylate, which is used to evenly disperse the fibers and additives, prevent fiber agglomeration, ensure the uniformity of paper quality, and help improve the comprehensive performance of the paper. The filler is calcium carbonate, which can improve the opacity, whiteness and printability of paper, and at the same time improve the stiffness of paper to a certain extent. However, adding too much may affect the strength of the paper and needs to be reasonably controlled.

[0097] This embodiment also discloses a method for preparing the aforementioned strong washed kraft paper hook, comprising the following steps:

[0098] (1) Pulping: Long-fiber wood pulp, short-fiber wood pulp and cotton pulp are respectively put into respective pulping equipment for pulping. The beating degree of long-fiber wood pulp is controlled at 40°SR and that of short-fiber wood pulp is controlled at 50°SR, so that the fibers have an appropriate degree of fibrillation and the bonding force between the fibers is improved. The synthetic fibers are separately opened to be fully dispersed, and then evenly mixed with the beaten long-fiber wood pulp, short-fiber wood pulp and cotton pulp according to a certain proportion.

[0099] (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in turn, and continue stirring for 30 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension.

[0100] (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, multiple pieces of uncured carbon fiber cloth that have been cut are placed, and then the forming device of the paper machine is used to perform preliminary dehydration and forming to form wet paper sheets. Then, the wet paper sheets are passed through the pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa, and the pressing time is adjusted according to the paper weight and equipment performance.

[0101] (4) Drying: After being pressed, the paper sheet enters the drying section and is dried by steam heating or hot air drying. The drying temperature is controlled at 140°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer 12 and the second inner layer 22. During the drying process, attention should be paid to the uniformity of temperature to avoid deformation or strength loss of the paper due to excessive local drying.

[0102] (5) Post-treatment: The dried paper is calendered as needed, and the calendering pressure is controlled at 10 MPa.

[0103] (6) Cutting: Figure 1 As shown, paper is cut to form two hook plates 10 and two connecting plates 20 that are integrally connected.

[0104] (7) Gluing: Glue is applied to corresponding positions on the two hook plates 10 and the two connecting plates 20 to form a first adhesive layer 31 and a second adhesive layer 32 .

[0105] (8) Folding and forming: Fold the two hook plates 10 and fix them together through the first adhesive layer 31 (such as Figure 3 ), and the two connecting plates 20 are bent relative to the two hook plates 10, the two connecting plates 20 extend horizontally, and the two hook plates 10 extend vertically (such as Figure 4 ).

[0106] When in use, the two hook plates 10 are extended outward from the bottom to the top through the slots on the top of the packaging box, and the second adhesive layers 32 on the two connecting plates 20 are bonded and fixed to the inner wall of the top of the packaging box.

[0107] Through use tests, it was found that the hook in this embodiment, which has the same thickness as ordinary paper, has a tensile strength of 1300 grams of tension per centimeter width and is not easily torn.

[0108] The design focus of the present invention is: by adopting the washed kraft paper material of the formula of the present invention, and cooperating with the structure and preparation method of the present invention to produce the hook, the hook has strong toughness, and the load-bearing capacity is effectively improved. There is no need to mount multiple layers of paper, the material loss is small, and the production efficiency is high, which brings convenience to production operations.

[0109] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A strong and tough washed kraft paper hook, characterized by: It includes two hook plates extending outward from the top of the packaging box and two connecting plates fixedly attached to the inner wall of the top of the packaging box; The two hook plates are symmetrical and integrally connected to each other, and the two hook plates are foldably arranged to each other. Both hook plates are provided with hook holes. After folding, the two hook plates are bonded and fixed by the first adhesive layer, and the two hook holes are directly connected to each other. Each hook plate includes a first outer layer and a first inner layer, the first outer layer is made of washed kraft paper, the first inner layer is inlaid and fixed in the first outer layer, and the first inner layer is made of carbon fiber material; The two connecting plates are symmetrical to each other and are integrally connected with the outer ends of the two hook plates respectively. The two connecting plates are bendably arranged relative to the two hook plates respectively. A second adhesive layer is arranged on the surface of each connecting plate. Each connecting plate includes a second outer layer and a second inner layer. The second outer layer is made of washed kraft paper. The second outer layer is integrally connected with the first outer layer. The second inner layer is inlaid and fixed in the second outer layer. The second inner layer is made of carbon fiber. The second inner layer is separated from the first inner layer. The washed kraft paper material includes the following raw materials in parts by weight: 55-70 parts of long fiber wood pulp; 35-45 parts of short fiber wood pulp; 15-18 parts of synthetic fiber; 20-25 parts of cotton pulp; 4-5 parts of wet strength agent; 2-3 parts of water repellent; 0.8-1.2 parts of dispersant; 25-30 parts of filler.

2. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The long-fiber wood pulp is coniferous wood pulp, the short-fiber wood pulp is broadleaf wood pulp, and the synthetic fiber is aramid fiber or polyvinyl alcohol fiber.

3. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The wet strength agent is polyamide polyamine epichlorohydrin.

4. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The water repellent is an alkyl ketene dimer.

5. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The dispersant is sodium polyacrylate.

6. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The filler is calcium carbonate.

7. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The inner sides of the two hook plates are coated with a first adhesive layer. After folding, the two first adhesive layers are bonded and fixed together.

8. The strong and tough washed kraft paper hook according to claim 1, characterized in that: The width of the connecting plate is greater than that of the hook plate, and the inner middle portion of the connecting plate is integrally connected with the outer end of the hook plate to form a T-shaped structure.

9. A method for preparing a strong and tough washed kraft paper hook according to any one of claims 1 to 8, characterized in that: The following steps are included: (1) beating: long fiber pulp, short fiber pulp and cotton pulp are respectively put into respective beating equipment for beating treatment, the beating degree of long fiber pulp is controlled at 30-40°SR, and the beating degree of short fiber pulp is controlled at 40-50°SR; and the synthetic fiber is separately opened to make it fully dispersed, and then mixed evenly with the beaten long fiber pulp, short fiber pulp and cotton pulp according to a proportion; (2) Slurry preparation: Add an appropriate amount of water to the slurry preparation tank, turn on the stirring device, first dissolve the dispersant in the water to form a uniform dispersion, then add the mixed fiber slurry, wet strength agent, water repellent and filler in sequence, and continue stirring for 30-60 minutes to ensure that all ingredients are fully mixed and evenly formed to form a stable pulp suspension; (3) Papermaking: The prepared pulp suspension is evenly sprayed onto the papermaking mesh through a headbox. During the spraying process, a plurality of uncured carbon fiber cloths that have been cut are placed. Then, the papermaking machine's forming device is used to perform preliminary dehydration and forming to form a wet paper sheet. Then, the wet paper sheet is passed through a pressing section to further remove moisture through mechanical pressure. During the pressing process, the pressure is controlled at 5-10 MPa. (4) Drying: After being pressed, the paper sheet enters the drying section and is dried by steam heating or hot air drying. The drying temperature is controlled at 125-140°C. At the same time, the uncured carbon fiber cloth is cured by heat to form the first inner layer and the second inner layer. (5) Post-treatment: The dried paper is calendered as needed, and the calendering pressure is controlled at 10-20 MPa; (6) Cutting: Cutting the paper to form two hook plates and two connecting plates connected in one piece; (7) Gluing: applying glue on corresponding positions of the two hook plates and the two connecting plates to form a first glue layer and a second glue layer; (8) Folding and forming: fold the two hook plates and fix them together through the first adhesive layer, and make the two connecting plates bend relative to the two hook plates respectively, the two connecting plates extend horizontally, and the two hook plates extend vertically.

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