Raw tissue paper and production method thereof

Abstract

The invention relates to raw paper of facial tissue and a production method of the raw paper. Different from the prior art, high-concentration pulping and glyoxal polyacrylamide dry strength agent technologies are matched to reduce the use amount of the long fiber pulp, the tensile strength of finished paper can be improved by increasing the specific energy consumption of the high-concentration pulping, and meanwhile, more hydroxyl sites are provided on fibers to be combined with the glyoxal polyacrylamide dry strength agent, so that the tensile strength of the finished paper is improved. The strength of finished paper is further improved. The glyoxal polyacrylamide dry strength agent can also reduce fine fibers in the system and improve the retention rate. The technology is simple in process, the strength of finished paper can be improved, the usage amount of long fibers is reduced, the cost of raw materials is saved, and the method is suitable for large-scale popularization.

Description

Technical Field

[0001] The invention relates to the field of daily paper manufacturing, and in particular to a facial tissue base paper and a production method thereof. Background Art

[0002] The raw materials used for facial tissue are mainly wood pulp fibers, which are divided into hardwood and coniferous wood. Hardwood, also known as hardwood, has shorter fibers, usually 0.8-1.1mm, and the paper strength is relatively low, but the growth cycle is short, usually 3-5 years. Coniferous wood, also known as softwood, has longer fibers, usually 2-3.5mm, and the paper strength is relatively high, but the growth cycle is longer, usually 15-25 years, so the price of coniferous wood is higher than that of hardwood. Under the same conditions, the greater the proportion of coniferous wood pulp used in production, the higher the cost.

[0003] In order to maintain the strength index of facial tissue base paper, especially high tensile strength, the proportion of coniferous wood pulp is generally 18-20%, and the production cost is relatively high; but to reduce the proportion of coniferous wood pulp, a large amount of chemical additives are generally added, which will make the base paper harder and affect the feel. Summary of the invention

[0004] In view of the above problems, the present application provides a low-cost, low-chemical additive, environmentally friendly facial tissue base paper and a production method thereof.

[0005] The first aspect of the present application provides a method for producing facial tissue base paper, comprising the following steps:

[0006] Slurry preparation:

[0007] Long-fiber softwood pulp: bleached softwood pulp is pulped at low consistency and refined using a double disc refiner;

[0008] Short-fiber hardwood pulp: Bleached commercial hardwood pulp is refined to high consistency.

[0009] Mixing slurry:

[0010] 15-18% long-fiber softwood pulp, 82-85% short-fiber hardwood pulp;

[0011] Copied:

[0012] A crescent-shaped paper machine is used to place pulp on the screen, press and dehydrate to obtain a wet paper web;

[0013] Drying wrinkles:

[0014] The paper is dried by a drying cylinder and corrugated with a corrugating alloy knife to obtain facial tissue base paper.

[0015] Different from the prior art, the present application adopts the technology of high-concentration pulping and glyoxal polyacrylamide dry strength agent to reduce the proportion of long fiber pulp. The increase in high-concentration pulping specific energy consumption can improve the tensile strength of the finished paper, and at the same time, more hydroxyl sites are provided on the fiber to combine with the glyoxal polyacrylamide dry strength agent to further improve the strength of the finished paper. The glyoxal polyacrylamide dry strength agent can also reduce fine fibers in the system and improve the retention rate. The technology of the present application has a simple process, can increase the strength of the finished paper, reduce the use of long fibers, save raw material costs, and is suitable for large-scale promotion.

[0016] Furthermore, the double-disc refining concentration is controlled at 3.0-5.0%, preferably 4.5%, the disc refining specific energy consumption is 120-140 kwh / t, the pulp throughput is 900-1000 L / min, the reflux rate is 300 L / min, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

[0017] Furthermore, the pulp concentration at the inlet of the high-concentration mill pressing screw is 5%, the pulp throughput is 3200-3800L / min, the beating degree before refining is 15-16°SR, the pulp dryness entering the high-concentration mill zone is 25-28%, and the beating degree after refining is 19-22°SR.

[0018] Furthermore, in the pulp preparation step, a wet strength agent is added to the pulp, with the addition amount of 8-10 kg / t pulp;

[0019] Furthermore, in the pulp preparation step, glyoxal polyacrylamide dry strength agent is also added to the pulp, and the added amount is 0.5-1 kg / t pulp.

[0020] Furthermore, the inlet for adding the glyoxal polyacrylamide is the inlet of a slurry pump.

[0021] Furthermore, in the high-concentration pulping, the equipment used is an Andritz high-concentration pulping machine, model CDI3pL, and the pulping specific energy consumption is controlled at 25 to 55 kwh / t pulp.

[0022] Furthermore, the speed of the crescent paper machine is 700-1900 m / min.

[0023] The second aspect of the present application provides a facial tissue base paper, which is produced using the production method described in the first aspect of the present application.

[0024] Furthermore, the width of the facial tissue base paper is 5650 mm and the gram weight is 12-30 g / m 2 .

[0025] The above-mentioned records related to the invention content are only an overview of the technical solution of the present application. In order to enable ordinary technicians in the field to more clearly understand the technical solution of the present application, and then implement it according to the written contents of the specification, and to make the above-mentioned purpose and other purposes, features and advantages of the present application easier to understand, the specific implementation mode and drawings of the present application are explained below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings are only used to illustrate the principles, implementation methods, applications, characteristics and effects of the specific embodiments of the present application and other related contents, and shall not be considered as limitations of the present application.

[0027] In the drawings of the specification:

[0028] Figure 1 This is the relationship diagram of specific energy consumption-beating degree / wet weight.

[0029] Figure 2 It is the relationship diagram between specific energy consumption and tensile index / bulk thickness;

[0030] Figure 3 It is the relationship diagram between specific energy consumption and average fiber length / average fiber width;

[0031] Figure 4 This is a relationship diagram between specific energy consumption and average morphology factor / fine fiber ratio. DETAILED DESCRIPTION

[0032] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0033] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0034] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0035] In the description of this application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that three relationships may exist, for example, A and / or B, which means: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this article generally indicates that the objects before and after are in an "or" logical relationship.

[0036] In the present application, terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship of quantity, priority or sequence between these entities or operations.

[0037] Without further limitations, in this application, the words "include", "comprises", "has" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0038] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than", "less than", "exceed" and the like are understood to exclude the number itself; expressions such as "above", "below", "within" and the like are understood to include the number itself. In addition, in the description of the embodiments of this application, "multiple" means more than two (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups", "multiple times", etc., unless otherwise clearly and specifically limited.

[0039] The first aspect of the present application provides a method for producing facial tissue base paper, comprising the following steps:

[0040] Slurry preparation:

[0041] Long-fiber softwood pulp: bleached softwood pulp is beaten at low concentration and refined using a double-disc refiner. The fibers are separated and cut appropriately at the same time.

[0042] Short-fiber hardwood pulp: Bleached commercial hardwood pulp is refined at high concentration. The use of high-concentration refined hardwood pulp can fully separate the fibers and retain the fiber length well, solving the problem of easy cutting caused by low-concentration beating and heavy beating, thereby greatly improving the utilization rate of short-fiber raw materials and reducing the amount of long fibers. Compared with low-concentration beating, it can better maintain the bulk.

[0043] Mixing slurry:

[0044] 15-18% long-fiber softwood pulp, 82-85% short-fiber hardwood pulp;

[0045] Copied:

[0046] A crescent-shaped paper machine is used to place pulp on the screen, press and dehydrate to obtain a wet paper web;

[0047] Drying wrinkles:

[0048] The paper is dried by a drying cylinder and corrugated with a corrugating alloy knife to obtain facial tissue base paper.

[0049] Different from the prior art, the present application adopts the technology of high-concentration pulping and glyoxal polyacrylamide dry strength agent to reduce the proportion of long fiber pulp used. The increase in high-concentration pulping specific energy consumption can improve the tensile strength of the finished paper, and at the same time, more hydroxyl sites are provided on the fiber to combine with the glyoxal polyacrylamide dry strength agent to further improve the strength of the finished paper. The glyoxal polyacrylamide dry strength agent can also reduce fine fibers in the system and improve the retention rate. The technology of the present application has a simple process, can increase the strength of the finished paper, reduce the proportion of long fibers used, save raw material costs, and is suitable for large-scale promotion.

[0050] There has long been a contradiction in the traditional pulping process: heavy pulping of low-concentration broadleaf pulp will result in severe cutting, high power consumption, and large thickness loss, while light pulping will result in a high proportion of long fibers and increased costs. The innovative use of high-concentration pulping to treat broadleaf pulp in this technical solution can fully separate the fibers into filaments while retaining the fiber length, solving the problem that heavy pulping with low-concentration pulping easily causes cutting, thereby greatly improving the utilization rate of short fiber raw materials, reducing the proportion of long fibers, and better maintaining bulk relative to low-concentration pulping. Due to the high concentration of the pulp and the large gap between the grinding discs in high-concentration pulping, the effect of pulping does not rely on the direct action of the grinding disc on the fibers, but relies on the mutual friction, extrusion, kneading, and twisting of the high-concentration pulp between the grinding discs, so that the fibers are beaten and a large amount of friction heat is generated, which softens the fibers and is conducive to the separation of the pulp. In high-concentration pulping, the beating degree increases slowly and the slurry has good water filtration performance. There are also significant differences between high-consistency pulping and low-consistency pulping in terms of fiber morphology. The fibers of high-consistency pulping have obvious brooming and longitudinal splitting. The fibers are soft and swellable. Most of the fibers are twisted and have good shrinkage properties, which can greatly improve the strength and tear resistance of paper.

[0051] Furthermore, the double-disc refining concentration is controlled at 3.0-5.0%, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

[0052] Preferably, the double-disc refining concentration is controlled at 4.5%.

[0053] Furthermore, the disc grinding specific energy consumption is 120-140 kwh / t, the slurry throughput is 900-1000 L / min, and the reflux volume is 300 L / min.

[0054] Furthermore, the high-concentration pulping concentration is 5%, the pulp throughput is 3200-3800 L / min, the beating degree before pulping is 15-16°SR, and the beating degree after pulping is 19-22°SR.

[0055] Furthermore, in the pulp preparation step, a wet strength agent is added to the pulp in an amount of 8-10 kg / t pulp.

[0056] Furthermore, in the pulp preparation step, glyoxal polyacrylamide dry strength agent is also added to the pulp, and the added amount is 0.5-1 kg / t pulp.

[0057] During the research and development, it was found that the low molecular weight glyoxal polyacrylamide dry strength agent combined with traditional low-concentration pulping has no obvious effect in the production of low-weight base paper, while the high molecular weight glyoxal polyacrylamide dry strength agent will make the base paper harder and affect the feel.

[0058] Furthermore, the addition port of the glyoxal polyacrylamide is the inlet of the slurry pump. The most ideal addition point of the glyoxal polyacrylamide dry strength agent (GPAM) is at the inlet of the slurry pump to ensure that the dry strength agent can be put on the net for forming as soon as possible after mixing with the slurry. Adding the online produced GPAM at the inlet of the slurry pump can ensure that it is fully mixed with the slurry on the net.

[0059] Furthermore, in the high-concentration pulping, the equipment used is an Andritz high-concentration pulping machine, model CDI3pL, and the pulping specific energy consumption is controlled at 25 to 55 kwh / t pulp.

[0060] Furthermore, the speed of the crescent paper machine is 700-1900 m / min.

[0061] Further, the wrinkling rate is 23-33%.

[0062] The second aspect of the present application provides a facial tissue base paper, which is produced using the production method described in the first aspect of the present application.

[0063] Furthermore, the width of the facial tissue base paper is 5650 mm and the gram weight is 12-30 g / m 2 .

[0064] The glyoxal polyacrylamide dry strength agent (GPAM) described in this embodiment is produced by cross-linking reaction of polyacrylamide and glyoxal. The glyoxal polyacrylamide dry strength agent can generate bonds and forces to improve the dry strength of paper and paperboard by reacting an aldehyde group on its molecular formula with a hydroxyl group on the fiber to form a covalent bond, thereby improving the temporary wet strength of paper.

[0065] In this embodiment, the wet strength agent is an environmentally friendly polyamide epoxy resin PAE, which meets the national requirements for food contact paper products.

[0066] In this embodiment, the pulping method is divided into two types: low-concentration pulping and high-concentration pulping. In low-concentration pulping, the fibers directly interact with the blades, and the fibers are subjected to strong impact, shearing and crushing, and a large number of fine fibers are generated, which leads to dehydration of the paper machine and unstable factors in the dryer coating; while in high-concentration pulping, the fibers rub and knead each other, the shearing effect is small, and the silk-splitting effect is good.

[0067] The beating degree mentioned in this application is the beating degree. After the reaction pulp passes through the refiner, the fibers are cut, split, swollen, and hydrated, which are the effects of the refinement. Beating is to use the mechanical action of the grinding disc teeth to treat the fibers in the pulp, so that they are loosened, appropriately cut, and separated; more importantly, the fibers absorb water and swell during beating, so that they have higher elasticity and plasticity, meet the requirements of paper machine production, so that the produced paper can reach the expected quality indicators. The beating degree indicates the water filtration performance of the pulp. Take 2 grams of absolute dry pulp, dilute to 1000 ml, and pass through an 80-mesh screen at 20°C. The amount of water discharged from the side tube of the Shaw beating degree meter is the result of the measurement. The beating degree is an indicator of the properties of paper stock. According to the beating degree of paper stock, it is possible to grasp the water filtration speed of the paper stock on the copper screen of the paper machine in the future, and it is also possible to summarize and predict the mechanical strength, tightness and manageability of the paper produced in the future. Therefore, mastering the beating degree of paper stock is an important technical control method in production.

[0068] Example 1: Effect of high-consistency refining specific energy consumption on paper sample performance

[0069] The bleached commercial hardwood pulp was refined at high concentration. The specific energy consumption was adjusted to 25kwh / t, 40kwh / t, and 55kwh / t under the condition that other process parameters remained unchanged. The high concentration mill outlet was sampled at the corresponding specific energy consumption, the pulp beating degree was tested, the fiber analysis was performed, and the paper sample bulk and tensile index were tested after papermaking. The results are as follows: Figure 1-Figure 4 shown.

[0070] Depend on Figure 1 It can be seen that with the increase of specific energy consumption, the beating degree increases, and there is no obvious regularity in wet weight. Figure 2 It can be seen that: with the increase of specific energy consumption, the tensile index increases, showing a positive correlation trend; the bulk decreases, showing a negative correlation trend. Figure 3 It can be seen that: with the increase of specific energy consumption, the average fiber length changes irregularly; the average fiber width does not change significantly. Figure 4 It can be seen that: with the increase of specific energy consumption, the average morphology factor increases accordingly, showing a positive correlation trend; the fine fiber ratio decreases accordingly, showing a positive correlation trend.

[0071] In short, with the increase of high-concentration grinding specific energy consumption, the beating degree, tensile index, average morphological factor (degree of fiber deformation) and fine fiber ratio increase, showing a positive correlation trend; the bulk decreases with the increase of high-concentration grinding specific energy consumption, showing a negative correlation trend. Compared with the blank sample without refining, the tensile index of the copy sheet increased by 31% when the specific energy consumption was 25kwh / t, the tensile index of the copy sheet increased by 39% when the specific energy consumption was 40kwh / t, and the tensile index of the copy sheet increased by 44% when the specific energy consumption was 55kwh / t.

[0072] Therefore, increasing the refining power can be used to increase the tensile strength of the finished paper, but the bulk will decrease. In this embodiment, the specific energy consumption is set to 25-55 kwh / t.

[0073] Example 2

[0074] The paper machine is a crescent paper machine with a width of 5650mm. It produces base paper for daily use. The paper weight is 20g / m 2 , vehicle speed is 1500m / min, and the pulp source is coniferous pulp board and broadleaf pulp board.

[0075] Slurry preparation:

[0076] Long fiber coniferous pulp: The bleached coniferous pulp is beaten at low concentration and refined using a double disc refiner; the double disc refiner concentration is controlled at 4.5%, the disc refiner specific energy consumption is 120-140 kwh / t, the pulp throughput is 900-1000 L / min, the reflux rate is 300 L / min, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

[0077] Short-fiber hardwood pulp: Andritz high-consistency pulper, model CDI3pL, is used to refine bleached commercial hardwood pulp at high consistency. The pulp concentration at the inlet of the high-consistency mill press screw is 5%, the pulp throughput is 3200-3800L / min, the beating degree before refining is 15-16°SR, the pulp dryness entering the high-consistency mill is 26%, and the beating degree after refining is 19-22°SR. The specific energy consumption of pulping is controlled at 25-55kwh / t pulp.

[0078] Mixing slurry:

[0079] 18% long-fiber softwood pulp, 82% short-fiber hardwood pulp;

[0080] A wet strength agent is also added to the pulp, with the addition amount of 10kg / t pulp;

[0081] Glyoxal polyacrylamide dry strength agent was added in an amount of 1kg / t pulp, and the addition port of glyoxal polyacrylamide was the inlet of the pulp pump.

[0082] Copied:

[0083] A crescent-shaped paper machine is used to place pulp on the screen, press and dehydrate to obtain a wet paper web;

[0084] Drying wrinkles:

[0085] The paper is dried by a drying cylinder and corrugated with a corrugating alloy knife to obtain facial tissue base paper.

[0086] Example 3

[0087] The paper machine is a crescent paper machine with a width of 5650mm. It produces base paper for daily use. The paper weight is 12g / m 2 , vehicle speed is 1000m / min, and the pulp source is coniferous pulp board and broadleaf pulp board.

[0088] Slurry preparation:

[0089] Long fiber coniferous pulp: The bleached coniferous pulp is beaten at low concentration and refined using a double disc refiner; the double disc refiner concentration is controlled at 4.5%, the disc refiner specific energy consumption is 120-140 kwh / t, the pulp throughput is 900-1000 L / min, the reflux rate is 300 L / min, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

[0090] Short-fiber hardwood pulp: Andritz high-consistency pulper, model CDI3pL, high-consistency pulping of bleached commercial hardwood pulp, the high-consistency pulping concentration is 5%, the pulp throughput is 3200-3800L / min, the beating degree before refining is 15-16°SR, and the beating degree after refining is 19-22°SR. The specific energy consumption of pulping is controlled at 25-55kwh / t pulp.

[0091] Mixing slurry:

[0092] 15% long-fiber softwood pulp, 85% short-fiber hardwood pulp;

[0093] A wet strength agent is also added to the pulp, with an addition amount of 8kg / t pulp;

[0094] Glyoxal polyacrylamide dry strength agent was added, the addition amount was 0.5kg / t pulp, and the addition port of glyoxal polyacrylamide was the inlet of the pulp pump.

[0095] Copied:

[0096] A crescent-shaped paper machine is used to apply pulp to the screen, press and dehydrate to obtain a wet paper web;

[0097] Drying wrinkles:

[0098] The paper is dried by a drying cylinder and corrugated with a corrugating alloy knife to obtain facial tissue base paper.

[0099] Example 4

[0100] The paper machine is a crescent paper machine with a width of 5650mm. It produces base paper for daily use. The paper weight is 20g / m 2 , vehicle speed is 1200m / min, and the pulp source is coniferous pulp board and broadleaf pulp board.

[0101] Slurry preparation:

[0102] Long-fiber coniferous pulp: The bleached coniferous pulp is beaten at a low concentration and refined using a double-disc refiner; the double-disc refiner concentration is controlled at 3.0-3.5%, the refiner specific energy consumption is 120-140 kwh / t, the pulp throughput is 900-1000 L / min, the reflux rate is 300 L / min, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

[0103] Short-fiber hardwood pulp: Andritz high-consistency pulper, model CDI3pL, high-consistency pulping of bleached commercial hardwood pulp, the high-consistency pulping concentration is 5%, the pulp throughput is 3200-3800L / min, the beating degree before refining is 15-16°SR, and the beating degree after refining is 19-22°SR. The specific energy consumption of pulping is controlled at 25-55kwh / t pulp.

[0104] Mixing slurry:

[0105] 16% long-fiber softwood pulp, 84% short-fiber hardwood pulp;

[0106] A wet strength agent is also added to the pulp, with the addition amount of 9kg / t pulp;

[0107] Glyoxal polyacrylamide dry strength agent was added, the addition amount was 0.8kg / t pulp, and the addition port of glyoxal polyacrylamide was the inlet of the pulp pump.

[0108] Copied:

[0109] A crescent-shaped paper machine is used to place pulp on the screen, press and dehydrate to obtain a wet paper web;

[0110] Drying wrinkles:

[0111] The paper is dried by a drying cylinder and corrugated with a corrugating alloy knife to obtain facial tissue base paper.

[0112] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of this application, this does not limit the scope of patent protection of this application. All technical solutions generated by replacing or modifying equivalent structures or equivalent processes based on the essential concept of this application using the contents recorded in the specification and drawings of this application, as well as directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are included in the scope of patent protection of this application.

Claims

1. A method for producing facial tissue base paper, characterized in that: The following steps are involved: Slurry preparation: Long-fiber softwood pulp: bleached softwood pulp is pulped at low consistency and refined using a double disc refiner; Short-fiber hardwood pulp: Bleached commercial hardwood pulp is refined to high consistency. Mixing slurry: 15-18% long-fiber softwood pulp, 82-85% short-fiber hardwood pulp; Copy: A crescent-shaped paper machine is used to apply pulp to the screen, press and dehydrate to obtain a wet paper web; Drying wrinkles: The paper is dried by a drying cylinder and creped with a creping blade to obtain facial tissue base paper.

2. The production method according to claim 1, characterized in that The double-disc refining concentration is controlled at 3.0-5.0%, the beating degree before refining is 12-13°SR, and the beating degree after refining is 30-38°SR.

3. The production method according to claim 1, characterized in that The pulp concentration at the high-concentration mill press screw inlet is 5%, the pulp throughput is 3200-3800L / min, the beating degree before refining is 15-16°SR, the pulp dryness entering the high-concentration mill zone is 25-28%, and the beating degree after refining is 19-22°SR.

4. The production method according to claim 1, characterized in that In the pulp preparation step, a wet strength agent is also added to the pulp, with an addition amount of 8-10 kg / t pulp.

5. The production method according to claim 1, characterized in that: In the pulp preparation step, a glyoxal polyacrylamide dry strength agent is also added to the pulp, and the added amount is 0.5-1 kg / t pulp.

6. The production method according to claim 5, characterized in that The inlet for adding glyoxal polyacrylamide is the inlet of the slurry pump.

7. The production method according to claim 1, characterized in that: In the high-concentration pulping, the equipment used is an Andritz high-concentration pulping machine, model CDI3pL, and the pulping specific energy consumption is controlled at 25 to 55 kwh / t pulp.

8. The production method according to claim 1, characterized in that: The speed of the crescent paper machine is 700-1900 m / min.

9. A facial tissue base paper, characterized in that: The facial tissue base paper is produced by the production method described in any one of claims 1-8.

10. The facial tissue base paper according to claim 9, characterized in that: The width of the facial tissue base paper is 5650 mm, and the gram weight is 12-30 g / m 2 .

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