Bobbin base paper and method for manufacturing bobbin base paper

Abstract

The application provides a bobbin base paper and a bobbin base paper manufacturing method, wherein the bobbin base paper comprises a bottom paper layer, a core paper layer, a lining paper layer and a surface paper layer which are sequentially arranged, each paper layer is made of mixed pulp material composed of pulp residue, wood fiber pulp, starch and waste paper pulp by the circular net forming technology, wherein the proportion of the pulp residue, the wood fiber pulp, the starch and the waste paper pulp in the mixed pulp material is 60%-80%, 10%-30%, 1%-5% and 0-15% respectively. By changing the proportion of the pulp residue, the wood fiber, the waste paper pulp and the starch, using the low-price wood fiber pulp, adding most of the pulp residue and reducing the use of the waste paper pulp, the manufacturing cost of the bobbin base paper is reduced, and the performance-price ratio of the bobbin base paper is improved.

Description

Technical Field

[0001] This invention relates to the field of papermaking technology, and more specifically, to a yarn tube base paper and its manufacturing method. Background Technology

[0002] With the advent of a low-profit era for cardboard boxes, manufacturers are striving to reduce production costs. Low-priced, high-performance base paper is gaining popularity in the market. Low-cost yarn tube base paper is no longer limited to paper tube processing; it's increasingly being used in cardboard box products, such as the interlayer of cardboard boxes and chemical paper drums. These yarn tube base papers require high physical strength, thus demanding high-precision papermaking. Traditional yarn tube base paper production uses all or most of waste pulp residue plus a small amount of waste paper. Increasing the proportion of waste paper to improve the strength of the yarn tube base paper would increase production costs, leading to reduced or even no profit margin. Summary of the Invention

[0003] The purpose of this invention is to provide a low-cost yarn tube base paper and a method for manufacturing yarn tube base paper.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] In a first aspect, the present invention provides a yarn tube base paper, comprising a base paper layer, a core paper layer, a liner paper layer and a face paper layer stacked sequentially, each paper layer being made from a mixed pulp composed of pulp residue, wood fiber pulp, starch and waste paper pulp by a rotary screen forming technology, wherein the proportions of pulp residue, wood fiber pulp, starch and waste paper pulp in the mixed pulp are 60%-80%, 10%-30%, 1%-5%, and 0-15%, respectively.

[0006] In one embodiment, the bottom paper layer is formed by two circular wire mesh cages, the core paper layer is formed by two circular wire mesh cages, the liner paper layer is formed by two circular wire mesh cages, and the face paper layer is formed by one circular wire mesh cage.

[0007] In one embodiment, the thickness of the base paper of the yarn tube is 0.4-0.75 mm, and the moisture content is 5%-10%; the basis weight of the bottom paper layer is 80-145 g / m², the basis weight of the core paper layer is 80-145 g / m², the basis weight of the liner paper layer is 80-145 g / m², and the basis weight of the face paper layer is 40-70 g / m².

[0008] In a second aspect, the present invention also provides a method for manufacturing yarn tube base paper, for producing the aforementioned yarn tube base paper, comprising the following steps:

[0009] S1. Preparation of the main pulp for yarn tube base paper: Prepare the main pulp composed of pulp residue, wood fiber pulp and waste paper pulp, and store it in the pulping tower after it is broken down by a high-consistency refiner.

[0010] S2. Sizing: The main slurry in the sizing tower is added to the sizing tanks corresponding to each of the bottom paper layer, core paper layer, liner paper layer and face paper layer, and a starch solution with a concentration of 2%-5% is added to each sizing tank.

[0011] S3. Dilution: The slurry from the slurry tank is diluted to 0.5%-1% and sent to the slurry pump, which is set up one-to-one with the slurry tank;

[0012] S4. Stabilization: Each of the base paper layer, core paper layer, liner paper layer and face paper layer is equipped with a high-level box, which stabilizes the pulp from the pulp pump through the high-level box;

[0013] S4. Dewatering and forming: Each of the base paper layer, core paper layer, liner paper layer and face paper layer is equipped with a cylindrical wire cage. The pulp from the high-level box is dewatered through the cylindrical wire cage, and the pulp concentration is increased from 0.5%-1% to 20%-25%.

[0014] S6. Pressing and drying: First, the raw materials of the face paper layer, liner paper layer, core paper layer and bottom paper layer formed by the cylinder wire are pressed to increase the concentration from 20%-25% to 46%-55%. Then, the raw materials are dried to increase the concentration from 46%-55% to 90%-95%.

[0015] S7. Calendering and winding: The dried yarn tube raw material is calendered and wound to obtain the finished yarn tube base paper.

[0016] In one embodiment, step S1 specifically includes the following steps:

[0017] S11. Pulping: Wood fiber pulp and waste paper are added into the pulper at a ratio of 70-100:0-30 to produce high-consistency pulp. The high-consistency pulp enters the discharge pulp tank and then the mixing tank.

[0018] S12. Mixing: Add pulp residue from other paper machines to the mixing tank. Mix the pulp residue with the high-consistency pulp from S11 at a ratio of 50-80:20-50 to prepare a mixed pulp.

[0019] S13, High-Concentration Sand Removal: The high-concentration slurry in S12 is fed into the high-concentration sand remover to remove heavy impurities inside and obtain a low-concentration slurry.

[0020] S14. Coarse screening: The low-concentration slurry obtained in S13 is fed into a pressure screen for screening to separate larger impurities and obtain coarse slurry.

[0021] S15, Low-Concentration Sand Removal: The coarse slurry obtained in S14 is fed into a low-concentration slag remover to remove fine sand particles and other heavy impurities, thus obtaining sand-removing slurry.

[0022] S16. Fine screening: The sand-removing slurry obtained in S15 is put into a fine screening pressure screen for screening to remove small impurities in the slurry and obtain clean slurry.

[0023] S17. Multi-disc thickener: The clean slurry obtained in S16 is fed into a multi-disc thickener for thickening to obtain concentrated slurry;

[0024] S18. High-consistency pulping: The concentrated pulp obtained in S17 is fed into a high-consistency pulping mill for thickening and pulping to obtain the main pulp.

[0025] S19. Storage: The main slurry obtained in S18 is stored in the slurry forming tower.

[0026] In one embodiment, in step S3, the slurry pump inlet is provided with a mixing pipe, which is connected to two slurry inlet pipes, one of which is connected to the slurry tank and the other is connected to the white water tank.

[0027] In one embodiment, in step S4, rosin gum and aluminum sulfate are further added to the slurry in the high-level tank.

[0028] In one embodiment, seven high-level boxes and seven circular wire mesh cages are provided, with each circular wire mesh cage corresponding to one of the high-level boxes; wherein,

[0029] The corresponding bottom paper layer is provided with two high-level boxes and two circular wire cages;

[0030] The corresponding core paper layer is provided with two high-level boxes and two circular wire cages;

[0031] Two high-level boxes and two circular wire mesh cages are provided for the corresponding liner layer;

[0032] A high-level box and a circular wire mesh cage are provided for the corresponding face paper layer.

[0033] In one embodiment, in step S5, a starch solution with a concentration of 2%-5% is sprayed onto the surface of each formed paper layer.

[0034] The beneficial effects of the technical solution provided by this invention are:

[0035] 1. The yarn tube base paper of the present invention reduces the manufacturing cost of the yarn tube base paper and improves its cost-effectiveness by changing the ratio of pulp residue, wood fiber, waste paper pulp and starch, using low-cost wood fiber pulp, and reducing the use of waste paper pulp by using mostly pulp residue.

[0036] 2. The manufacturing method of yarn tube base paper utilizes a high-consistency refiner, which fully disperses and filaments, improves fiber hydrogen bonding, and enhances sheet strength, bursting strength, and interlayer bonding strength. The refining of wood fiber pulp is particularly effective, significantly increasing its bonding strength and thus meeting the strength requirements of yarn tube base paper.

[0037] 3. Use in-pulp starch and sprayed starch to improve the ring crush strength, bursting strength and interlayer bonding strength of the paper.

[0038] 4. The use of 7 circular wire mesh cages improves the uniformity and density of the paper sheets, enhancing the paper's applicability. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below.

[0040] Figure 1 This is a flowchart of the yarn tube base paper manufacturing process provided in one embodiment of the present invention. Detailed Implementation

[0041] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the invention. It should be understood that the accompanying drawings and embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the invention.

[0042] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0043] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "connection" can refer to a direct connection or an indirect connection via intermediate components (elements). The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the following description.

[0044] See Figure 1 , Figure 1 This is a process flow diagram for manufacturing yarn tube base paper according to one embodiment of the present invention, which is used to make yarn tube base paper, improve paper performance, and reduce the production cost of yarn tube base paper.

[0045] This invention provides a yarn tube base paper, comprising a base paper layer, a core paper layer, a liner paper layer, and a face paper layer stacked sequentially. Each paper layer is made from a mixed pulp composed of pulp residue, wood fiber pulp, starch, and waste paper pulp through a rotary screen forming technology. In the mixed pulp, the proportions of pulp residue, wood fiber pulp, starch, and waste paper pulp are 60%-80%, 10%-30%, 1%-5%, and 0-15%, respectively.

[0046] By altering the proportions of pulp residue, wood fiber, waste paper pulp, and starch, and using inexpensive wood fiber pulp while minimizing the use of waste paper pulp, the manufacturing cost of yarn tube base paper is reduced, thus improving its cost-effectiveness. Furthermore, the use of in-pulp starch and sprayed starch enhances the paper's ring crush strength, bursting strength, and interlayer bonding strength.

[0047] In one embodiment, the base paper layer is formed using two circular wire mesh cages, the core paper layer is formed using two circular wire mesh cages, the liner paper layer is formed using two circular wire mesh cages, and the face paper layer is formed using one circular wire mesh cage. By forming multiple circular wire mesh cages, the uniformity and density of the yarn tube base paper are improved, thereby enhancing the applicability of the paper.

[0048] In one embodiment, the basis weight of the yarn tube base paper is 300-500 g / m², wherein the basis weight of the bottom paper layer is 80-145 g / m², the basis weight of the core paper layer is 80-145 g / m², the basis weight of the liner paper layer is 80-145 g / m², and the basis weight of the face paper layer is 40-70 g / m².

[0049] The physical properties of the base paper for the yarn tube are as follows: 1. Thickness: 0.4-0.75 mm; 2. Moisture content: 5-10%; 3. Ring crush index (longitudinal): ≥15 N.m / g; 4. Interlaminar bond strength: ≥350 J / m²; 5. Water absorption (COBB value): 150-400 g / m²; 6. Bursting strength index: ≥2.2 kPa.m² / g; 7. Broadband basis weight difference: ≤5.0%.

[0050] In a second aspect, the present invention also provides a method for manufacturing yarn tube base paper, for producing the aforementioned yarn tube base paper, comprising the following steps:

[0051] S1. Preparation of the main pulp for yarn tube base paper: Prepare the main pulp composed of pulp residue, wood fiber pulp and waste paper pulp, and store it in the pulping tower after it is broken down into fibers by a high-consistency refiner.

[0052] In step S1, a high-consistency refiner is used to fully break down the fibers, improve fiber hydrogen bonding, and enhance the ring crush strength, bursting strength, and interlaminar bonding strength of the paper sheet. The effect is particularly significant for the refining of wood fiber pulp, greatly improving its bonding strength.

[0053] This allows for an increase in the proportion of wood fiber pulp and pulp residue while reducing the proportion of waste paper pulp, based on meeting the strength requirements of the yarn tube base paper. Lower-priced wood fiber pulp and pulp residue can be used to replace higher-priced waste paper pulp, thus reducing the cost of the yarn tube base paper.

[0054] S2. Sizing: The main pulp in the pulping tower is added to the sizing tanks corresponding to each paper layer, namely the bottom paper layer, core paper layer, liner paper layer and face paper layer. A starch solution with a concentration of 2%-5% is added to each sizing tank. By adding starch solution to the pulp, the ring crush strength, bursting strength and interlayer bonding strength of the formed paper sheets are improved.

[0055] S3. Dilution: The slurry from the slurry tank is diluted to 0.5%-1% and sent to the slurry pump, which is set up one-to-one with the slurry tank.

[0056] S4. Stabilization: Each of the base paper layer, core paper layer, liner paper layer and face paper layer is equipped with a high-level box, which stabilizes the slurry from the slurry pump.

[0057] S4. Dewatering and forming: Each of the base paper layer, core paper layer, liner paper layer and face paper layer is equipped with a cylindrical wire cage. The pulp from the high-level box is dewatered through the cylindrical wire cage, and the pulp concentration is increased from 0.5%-1% to 20%-25%.

[0058] S6. Pressing and Drying: First, the raw materials of the face paper layer, liner paper layer, core paper layer and bottom paper layer formed by the cylinder wire are pressed to increase the concentration from 20%-25% to 46%-55%. Then, the raw materials are dried to increase the concentration from 46%-55% to 90%-95%.

[0059] S7. Calendering and winding: The dried yarn tube raw material is calendered and wound to obtain the finished yarn tube base paper.

[0060] In one embodiment, step S1 specifically includes the following steps:

[0061] S11. Pulping: Wood fiber pulp and waste paper are added to the pulper at a ratio of 70-100:0-30 to produce high-consistency pulp. The high-consistency pulp enters the discharge pulp tank and then the mixing tank.

[0062] S12. Mixing: Add pulp residue from other paper machines to the mixing tank. Mix the pulp residue with the high-consistency pulp from S11 at a ratio of 50-80:20-50 to prepare a mixed pulp.

[0063] S13, High-Concentration Sand Removal: The high-concentration slurry in S12 is fed into the high-concentration sand remover to remove heavy impurities and obtain a low-concentration slurry.

[0064] S14. Coarse screening: The low-concentration slurry obtained in S13 is fed into a pressure screen for screening to separate larger impurities and obtain coarse slurry.

[0065] S15, Low-Concentration Sand Removal: The coarse slurry obtained in S14 is fed into a low-concentration slag remover to remove fine sand particles and other heavy impurities, thus obtaining a sand-removed slurry.

[0066] S16. Fine screening: The sand-removing slurry obtained in S15 is put into a fine screening pressure screen for screening to remove small impurities in the slurry and obtain clean slurry.

[0067] S17. Multi-disc thickener: The clean slurry obtained in S16 is fed into a multi-disc thickener for thickening to obtain concentrated slurry.

[0068] S18. High-consistency pulping: The concentrated pulp obtained in S17 is fed into a high-consistency refiner for thickening and pulping to obtain the main pulp.

[0069] S19. Storage: The main slurry obtained in S18 is stored in the slurry forming tower.

[0070] In one embodiment, in step S3, the slurry pump inlet is provided with a mixing pipe, which is connected to two slurry inlet pipes, one of which is connected to the slurry tank and the other is connected to the white water tank.

[0071] In one embodiment, in step S4, rosin and aluminum sulfate are further added to the slurry in the high-level tank to control the water absorption index of the formed paper sheet.

[0072] In one embodiment, seven high-level boxes and seven circular wire mesh cages are provided, with each circular wire mesh cage corresponding to one of the high-level boxes. Specifically, two high-level boxes and two circular wire mesh cages are provided for each bottom paper layer; two high-level boxes and two circular wire mesh cages are provided for each core paper layer; two high-level boxes and two circular wire mesh cages are provided for each liner paper layer; and one high-level box and one circular wire mesh cage are provided for each face paper layer. Dewatering and forming using multiple circular wire mesh cages improves the uniformity and density of the paper sheet, thus enhancing its usability.

[0073] In one embodiment, in step S5, a starch solution with a concentration of 2%-5% is sprayed onto the surface of each formed paper layer to further improve the ring crush strength, bursting strength and interlayer bonding strength of the paper.

[0074] The performance test results of the yarn tube base paper of this invention are shown in the table below:

[0075]

[0076] Metallographic analysis shows that the yarn tube base paper of this invention has a significant product bonding mechanism. The paper passes tests for thickness, ring crush, burst strength and water absorption, and meets the customer's usage requirements.

[0077] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention is not limited to the specific combination of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions as those in the present invention.

[0078] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A bobbin base paper manufacturing method, wherein the bobbin base paper comprises a bottom paper layer, a core paper layer, a backing paper layer and a face paper layer arranged in sequence, each paper layer is made of mixed pulp composed of pulp residue, wood fiber pulp, starch and waste paper pulp by the cylinder molding technology, and the proportion of each of the pulp residue, wood fiber pulp, starch and waste paper pulp in the mixed pulp is 60%-80%, 10%-30%, 1%-5% and 0-15% in sequence, characterized in that, A yarn tube base paper for papermaking, comprising the following steps: S1, preparing a main pulp of the yarn tube base paper: preparing a main pulp composed of pulp residue, wood fiber pulp and waste paper pulp, and after being defibrated by a high consistency refiner, the main pulp is stored in a pulp tower; S2, sizing: the main pulp in the pulp tower is added to the corresponding sizing pool of each paper layer of the bottom paper layer, the core paper layer, the lining paper layer and the surface paper layer, and a starch solution with a concentration of 2%-5% is added to each sizing pool; S3, dilution: the pulp from the sizing pool is diluted to 0.5%-1% and sent to a blow pump, which is arranged one-to-one with the sizing pool; S4, stabilization: a high tank is arranged corresponding to the bottom paper layer, the core paper layer, the lining paper layer and the surface paper layer, and the pulp from the blow pump is stabilized through the high tank; S4, dewatering and forming: a cylinder screen cage is arranged corresponding to the bottom paper layer, the core paper layer, the lining paper layer and the surface paper layer, and the pulp from the high tank is dewatered through the cylinder screen cage, and the pulp concentration is increased from 0.5%-1% to 20%-25%; S6, pressing and drying: the raw materials of the surface paper layer, the lining paper layer, the core paper layer and the bottom paper layer formed by the cylinder are pressed first, and the concentration is increased from 20%-25% to 46%-55%, and then the raw materials are dried, and the concentration is increased from 46%-55% to 90%-95%; S7, calendering and winding: the dried yarn tube raw material is calendered and wound to obtain the finished yarn tube base paper.

2. The bobbin base paper manufacturing method according to claim 1, characterized by, Step S1 specifically comprises the following steps: S11, pulping: wood fiber pulp and waste paper are added to a pulper at a ratio of 70-100:0-30 for pulping to obtain a high consistency pulp, which is then discharged into a discharge pulp tank and then into a mixing tank; S12, mixing: pulp residue from other paper machines is added to the mixing tank, and the pulp residue and the high consistency pulp of S11 are mixed at a ratio of 50-80:20-50 to prepare a mixed pulp; S13, high consistency sand removal: the high consistency pulp in S12 is put into a high consistency sand remover to remove internal heavy impurities and obtain a low consistency pulp; S14, coarse screening: the low consistency pulp obtained in S13 is put into a pressure screen for screening to separate large-sized impurities and obtain a coarse screened pulp; S15, low consistency sand removal: the coarse screened pulp obtained in S14 is put into a low consistency sand remover to remove fine sand and other heavy impurities and obtain a sand-removed pulp; S16, fine screening: the sand-removed pulp obtained in S15 is put into a fine screening pressure screen for screening to remove small-sized impurities in the pulp and obtain a clean pulp; S17, multi-disc thickening: the clean pulp obtained in S16 is put into a multi-disc thickener for thickening to obtain a thickened pulp; S18, high consistency beating: the thickened pulp obtained in S17 is sent to a high consistency refiner for beating to obtain the main pulp; S19, storage: the main pulp obtained in S18 is stored in a pulp tower.

3. The bobbin base paper manufacturing method according to claim 1, characterized by, In step S3, the inlet of the blow pump is provided with a mixing pipe, and two pulp inlet pipes are connected to the mixing pipe, one of which is connected to the sizing pool, and the other is connected to the white water tank.

4. The bobbin base paper manufacturing method according to claim 1, characterized by, In step S4, rosin size and aluminum sulfate are further added to the pulp in the high tank.

5. The bobbin base paper manufacturing method according to claim 1, characterized by, The high-position boxes and the cylinder mould cages are each provided with seven, and the cylinder mould cage and the high-position box are one-to-one corresponding arrangement; wherein, Two high-position boxes and two cylinder mould cages are arranged corresponding to the bottom paper layer; Two high-position boxes and two cylinder mould cages are arranged corresponding to the core paper layer; Two high-position boxes and two cylinder mould cages are arranged corresponding to the lining paper layer; One high-position box and one cylinder mould cage are arranged corresponding to the surface paper layer.

6. The bobbin base paper manufacturing method according to claim 1, characterized by, In step S5, the surface of the paper sheet of each paper layer is sprayed with a starch solution with a concentration of 2%-5%.

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