Preparation process of ultrathin absorbent paper

Abstract

The invention belongs to the technical field of hygienic product materials, and particularly relates to a preparation process of ultrathin absorbent paper.The ultrathin absorbent paper is prepared from, by weight, 15-35 parts of base paper raw pulp, 3-5.5 parts of SAP, 0.2-0.4 part of wet strength agent, 0.8-1.2 parts of passivating agent and 20 parts of wet paper pulp, the wet paper pulp is prepared based on fluff pulp and softwood pulp through defibering treatment, and the wet strength agent and the passivating agent are added into the wet paper pulp. After being compounded with a passivating agent, an oily physical barrier can be formed by virtue of rich hydrophobic groups in a molecular chain, so that the direct contact capacity of the SAP and water molecules is reduced, the water grabbing phenomenon of the SAP is improved, meanwhile, the technological process is improved, and the blanking uniformity and the production efficiency of the SAP are improved; a safer, more efficient and more stable technical scheme is provided for industrial production of the absorbent paper.

Description

Technical Field

[0001] The invention belongs to the technical field of sanitary product materials, and particularly relates to a preparation process of ultra-thin absorbent paper. Background Art

[0002] As a special kind of household paper, absorbent paper is widely used in the field of sanitary materials, especially in the absorbent core, where it plays a key role in absorbing and storing water molecules. Its main absorption component is a high molecular absorbent resin (SAP), which is compounded with fiber materials to achieve the functions of water absorption, diversion and distribution. However, the absorbent paper on the market still has significant defects in the preparation process. In the traditional dry compounding process, SAP and fluff pulp are mainly combined by mechanical means, and the two are physically dispersed. This combination method not only makes SAP easy to separate from the fiber material, affecting the overall performance of the absorbent paper, but also may cause allergic reactions to some sensitive people due to direct contact with the skin by SAP particles. Although the wet compounding process can improve the combination of SAP and fiber to a certain extent, there is a phenomenon of "water grabbing" by the absorbent resin during the production process, which leads to a significant attenuation of its water absorption performance. In addition, the wet process is also prone to production instability problems, such as uneven distribution of SAP polymers, particle drift and clogging of equipment, etc., which affects product quality and production efficiency.

[0003] Therefore, it is particularly important to solve problems such as unstable material bonding, attenuation of water absorption performance and potential skin safety during the production and use of absorbent paper by improving existing technologies and processes. Summary of the invention

[0004] In view of the above situation, the present invention provides a preparation process of ultra-thin absorbent paper, uses a passivator to introduce oily hydrophobic groups on the SAP material, combines passivation technology and optimized composite papermaking process, and develops a new type of absorbent paper. Relying on strong chemical bonding, the "water grabbing" phenomenon of SAP is greatly improved, the comprehensive performance of the absorbent paper is improved, the defects of traditional processes are overcome, and the continuity and stability of production are improved.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows: The invention provides a preparation process of ultra-thin absorbent paper, which is used for preparing the ultra-thin absorbent paper. The ultra-thin absorbent paper comprises the following raw materials in parts by weight: 15-35 parts of base paper pulp, 3-5.5 parts of SAP, 0.2-0.4 parts of wet strength agent, 0.8-1.2 parts of passivator and 20 parts of wet paper pulp.

[0006] Furthermore, the passivator is composed of the following raw materials in weight percentage: 50% SDBS (sodium dodecylbenzene sulfonate), 25% TX-10 (alkylphenol polyoxyethylene ether) and 25% OP-10 (octylphenol polyoxyethylene ether).

[0007] Furthermore, the wet strength agent is selected from any one of PEI (polyethyleneimine resin), UF (urea-formaldehyde resin) and PAE (polyamide polyamine epichlorohydrin resin).

[0008] Furthermore, the base paper pulp comprises the following raw materials in weight percentage: 40% fluff pulp and 60% coniferous wood pulp, and the base paper pulp is prepared by crushing 40% fluff pulp and 60% coniferous wood pulp.

[0009] Further, the wet pulp comprises the following raw materials in weight percentage: 40% fluff pulp and 60% coniferous wood pulp, and the preparation process of the wet pulp comprises the following steps: S1: Weigh fluff pulp and coniferous wood pulp in a mass ratio of 2:3 and place them in a pulper for 10 min to obtain wet paper stock; S2: The wet paper stock obtained in step S1 is transferred to a deflaker and deflaked at a power of 30 kWh / t to obtain wet paper pulp, with the beating degree controlled to be 13-15°SR and the wet weight to be 23-24 g.

[0010] The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: Weigh 15-35 parts of base paper pulp and beat it in a pulper at a power of 40 kWh / t to obtain base paper for copying, and control the beating degree to be 15-18°SR and the wet weight to be 19-21 g; Step 2: Weigh 0.2-0.4 parts of wet strength agent, and use a papermaking machine to paper the base paper obtained in step 1. During the papermaking process, the weighed wet strength agent is continuously added to obtain the base paper. The base paper weight is controlled to be 15-35 g / m 2 , longitudinal dry strength 5-7 N / m, longitudinal wet tensile strength 0.3-0.5 N / m, base paper density 175-177 kg / m 3 ; Step 3: After the base paper obtained in step 2 is unwound through an unwinding frame, an unwound base paper is obtained, 20 parts of wet pulp and 0.8-1.2 parts of a passivating agent are weighed and mixed, and then papermaking is performed in a vacuum rotary screen copying machine to obtain wet paper. The vacuum rotary screen copying machine includes a feeder, a guide roller 1, a guide roller 2, a guide roller 3, a traction roller, an upper pressure roller, a lower pressure roller, a support roller, a felt and a drying cylinder; Step 4: Weigh 3-5.5 portions of SAP and place them in the feeder. Control the SAP feed rate to 10-60 g / m 2 After starting the feeding, SAP will be dispersed on the surface of the wet paper. At the same time, the unwinding base paper is introduced into the upper and lower pressing rollers by the traction rollers, and is compounded and squeezed with the wet paper with SAP dispersed on the surface. Then, it is pressed, dried, wrinkled and rolled up by the rollers and drying cylinders to obtain ultra-thin absorbent paper.

[0011] Furthermore, the blanking machine is located above the blanket.

[0012] Furthermore, the angle between the unwinding base paper and the felt between the traction roller and the upper pressure roller is 45°.

[0013] Furthermore, the feeder is heated and insulated by oil pipes.

[0014] The beneficial effects achieved by the present invention are as follows: The ultra-thin absorbent paper prepared by the present invention uses fluff pulp and coniferous wood pulp as the main pulp base paper. By adding a passivator in the wet papermaking process, the absorbent paper absorption performance attenuation defect caused by SAP "grabbing water" can be effectively solved. The abundant hydrophobic alkyl chains, aromatic structures, sulfonic acid groups and other surface active groups and weak polar groups such as polyoxyethylene chains in the passivator can physically shield the hydrophilic groups such as carboxyl groups and hydroxyl groups of SAP, reduce the direct contact ability of SAP with water molecules, and form a layer of molecular oil on the surface of SAP. barrier; in addition, the present invention optimizes the preparation process of absorbent paper, combines a vacuum rotary screen copying machine, a polymer passivation technology and an unwinding frame, provides an improved preparation method, greatly improves production efficiency, and adds a traction roller, so that the angle between the base paper and the blanket is adjusted to 45°, avoiding the SAP powdery fine particles flying out of the wet paper and then swelling and adsorbing on water and clogging the blanket, thereby ensuring continuous and stable production. The oil pipe heating and heat preservation design adopted by the feeding machine can effectively prevent SAP from gelling in a water vapor environment and causing uneven feeding.

[0015] The present invention improves the performance of absorbent paper and the reliability of the production process by improving the passivation technology and optimizing the composite process, reduces the amount of SAP used, and provides a safer, more efficient and more stable technical solution for the industrial production of absorbent paper. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a process flow chart of preparing ultra-thin absorbent paper; Figure 2 Schematic diagram of the production line of Examples 1-4 and Comparative Example 1 in a vacuum rotary screen copying machine; Figure 3 The results of the back-seepage test of Examples 1-4 and Comparative Example 1 are shown. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0019] In the following embodiments, the preparation process of the ultra-thin absorbent paper is as follows Figure 1 As shown, the working process of the vacuum rotary screen copying machine is as follows Figure 2 As shown, unless otherwise specified, all methods are conventional; the materials used in the following embodiments, unless otherwise specified, are new materials purchased from the market.

[0020] Example 1: This example provides a process for preparing ultrathin absorbent paper, which is used to prepare ultrathin absorbent paper. The ultrathin absorbent paper comprises the following raw materials in parts by weight: 25 parts of base paper pulp, 4.5 parts of SAP, 0.3 parts of PEI, 1 part of passivator and 20 parts of wet pulp.

[0021] The wet pulp comprises the following raw materials in parts by weight: 12 parts of fluff pulp and 18 parts of coniferous wood pulp. The specific preparation process comprises the following steps: S1: Weigh 12 parts of fluff pulp and 18 parts of softwood pulp and place them in a pulper for 10 minutes to obtain wet paper stock; S2: The wet paper stock obtained in step S1 is transferred to a deflaker and deflaked at 30 kWh / t to obtain wet paper pulp. The beating degree and wet weight of the wet paper pulp are monitored and controlled in real time using a beating degree meter and a pulp fiber wet weight measuring instrument. The beating degree is controlled to be 13°SR and the wet weight to be 24 g.

[0022] The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: Weigh 25 parts of base paper pulp and beat it in a pulper at a power of 40 kWh / t to obtain base paper for copying, and control the beating degree to be 16°SR and the wet weight to be 20 g; Step 2: Weigh 0.3 parts of PEI, and use a papermaking machine to paper the base paper obtained in step 1. During the papermaking process, the weighed wet strength agent is continuously added to obtain the base paper. The base paper weight is controlled to be 20 g / m 2 , longitudinal dry strength 6 N / m, longitudinal wet tensile strength 0.4 N / m, base paper density 177 kg / m 3 ; Step 3: After the base paper obtained in step 2 is unwound through an unwinding frame, an unwound base paper is obtained, 20 parts of wet paper pulp and 1 part of a passivating agent are weighed and mixed, and then papermaking is performed in a vacuum rotary screen copying machine to obtain wet paper. The vacuum rotary screen copying machine includes a feeder, a guide roller 1, a guide roller 2, a guide roller 3, a traction roller, an upper pressure roller, a lower pressure roller, a support roller, a felt and a drying cylinder; Step 4: Weigh 4.5 portions of SAP and place them in the feeder. Control the SAP feed rate to 30 g / m 2 After starting the feeding, SAP will be dispersed on the surface of the wet paper. At the same time, the unwinding base paper is introduced into the upper and lower pressing rollers by the traction rollers, and is compounded and squeezed with the wet paper with SAP dispersed on the surface. Then, it is pressed, dried, wrinkled and rolled up by the rollers and drying cylinders to obtain ultra-thin absorbent paper.

[0023] Example 2: This example provides a process for preparing ultrathin absorbent paper, which is used to prepare ultrathin absorbent paper. The ultrathin absorbent paper comprises the following raw materials in parts by weight: 15 parts of base paper pulp, 9 parts of coniferous wood pulp, 3 parts of SAP, 0.2 parts of UF, 0.8 parts of passivator and 20 parts of wet pulp.

[0024] The wet pulp comprises the following raw materials in parts by weight: 12 parts of fluff pulp and 18 parts of coniferous wood pulp. The specific preparation process comprises the following steps: S1: Weigh 12 parts of fluff pulp and 18 parts of softwood pulp and place them in a pulper for 10 minutes to obtain wet paper stock; S2: The wet paper stock obtained in step S1 is transferred to a deflaker and deflaked at 30 kWh / t to obtain wet paper pulp. The beating degree and wet weight of the wet paper pulp are monitored and controlled in real time using a beating degree meter and a pulp fiber wet weight measuring instrument. The beating degree is controlled to be 15°SR and the wet weight to be 23 g.

[0025] The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: Weigh 15 parts of base paper pulp and beat it in a pulper at a power of 40 kWh / t to obtain base paper for copying, and control the beating degree to be 18°SR and the wet weight to be 19 g; Step 2: Weigh 0.2 parts of UF, and use a papermaking machine to paper the base paper obtained in step 1. During the papermaking process, the weighed wet strength agent is continuously added to obtain the base paper. The base paper weight is controlled to be 25 g / m 2 , longitudinal dry strength 7 N / m, longitudinal wet tensile strength 0.3 N / m, base paper density 175 kg / m 3 ; Step 3: After the base paper obtained in step 2 is unwound through an unwinding frame, an unwound base paper is obtained, 20 parts of wet paper pulp and 0.8 parts of a passivating agent are weighed and mixed, and then papermaking is performed in a vacuum rotary screen copying machine to obtain wet paper. The vacuum rotary screen copying machine includes a feeder, a guide roller 1, a guide roller 2, a guide roller 3, a traction roller, an upper pressure roller, a lower pressure roller, a support roller, a felt and a drying cylinder; Step 4: Weigh 3 portions of SAP and place them in the feeder. Control the SAP feed rate to 10 g / m 2After starting the feeding, SAP will be dispersed on the surface of the wet paper. At the same time, the unwinding base paper is introduced into the upper and lower pressing rollers by the traction rollers, and is compounded and squeezed with the wet paper with SAP dispersed on the surface. Then, it is pressed, dried, wrinkled and rolled up by the rollers and drying cylinders to obtain ultra-thin absorbent paper.

[0026] Example 3: This example provides a process for preparing ultrathin absorbent paper, which is used to prepare ultrathin absorbent paper. The ultrathin absorbent paper comprises the following raw materials in parts by weight: 35 parts of base paper pulp, 5.5 parts of SAP, 0.4 parts of PAE, 1.2 parts of passivator and 20 parts of wet pulp.

[0027] The wet pulp comprises the following raw materials in parts by weight: 12 parts of fluff pulp and 18 parts of coniferous wood pulp. The specific preparation process comprises the following steps: S1: Weigh 12 parts of fluff pulp and 18 parts of softwood pulp and place them in a pulper for 10 minutes to obtain wet paper stock; S2: The wet paper stock obtained in step S1 is transferred to a deflaker and deflaked at 30 kWh / t to obtain wet paper pulp. The beating degree and wet weight of the wet paper pulp are monitored and controlled in real time using a beating degree meter and a pulp fiber wet weight measuring instrument. The beating degree is controlled to be 14°SR and the wet weight to be 23 g.

[0028] The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: Weigh 35 parts of base paper pulp and beat it in a pulper at a power of 40 kWh / t to obtain base paper for copying, and control the beating degree to be 17°SR and the wet weight to be 21 g; Step 2: Weigh 0.2 parts of PAE, and use a papermaking machine to paper the base paper obtained in step 1. During the papermaking process, the weighed wet strength agent is continuously added to obtain the base paper. The base paper weight is controlled to be 35 g / m 2 , longitudinal dry strength 5 N / m, longitudinal wet tensile strength 0.5 N / m, base paper density 176 kg / m 3 ; Step 3: After the base paper obtained in step 2 is unwound through an unwinding frame, an unwound base paper is obtained, 20 parts of wet paper pulp and 1.2 parts of a passivating agent are weighed and mixed, and then papermaking is performed in a vacuum rotary screen copying machine to obtain wet paper. The vacuum rotary screen copying machine includes a feeder, a guide roller 1, a guide roller 2, a guide roller 3, a traction roller, an upper pressure roller, a lower pressure roller, a support roller, a felt and a drying cylinder; Step 4: Weigh 5.5 portions of SAP and place them in the feeder. Control the SAP feed rate to 60 g / m 2 After starting the feeding, SAP will be dispersed on the surface of the wet paper. At the same time, the unwinding base paper is introduced into the upper and lower pressing rollers by the traction rollers, and is compounded and squeezed with the wet paper with SAP dispersed on the surface. Then, it is pressed, dried, wrinkled and rolled up by the rollers and drying cylinders to obtain ultra-thin absorbent paper.

[0029] Example 4: This example provides a process for preparing ultrathin absorbent paper, which is used to prepare ultrathin absorbent paper. The ultrathin absorbent paper comprises the following raw materials in parts by weight: 20 parts of base paper pulp, 12 parts of coniferous wood pulp, 3 parts of SAP, 0.4 parts of PAE, 1 part of passivator and 20 parts of wet pulp.

[0030] The wet pulp comprises the following raw materials in parts by weight: 12 parts of fluff pulp and 18 parts of coniferous wood pulp. The specific preparation process comprises the following steps: S1: Weigh 12 parts of fluff pulp and 18 parts of softwood pulp and place them in a pulper for 10 minutes to obtain wet paper stock; S2: The wet paper stock obtained in step S1 is transferred to a deflaker and deflaked at 30 kWh / t to obtain wet paper pulp. The beating degree and wet weight of the wet paper pulp are monitored and controlled in real time using a beating degree meter and a pulp fiber wet weight measuring instrument. The beating degree is controlled to be 13°SR and the wet weight to be 23 g.

[0031] The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: Weigh 20 parts of base paper pulp and beat it in a pulper at a power of 40 kWh / t to obtain base paper for copying, and control the beating degree to be 15°SR and the wet weight to be 20 g; Step 2: Weigh 0.4 parts of PAE, and use a papermaking machine to paper the base paper obtained in step 1. During the papermaking process, the weighed wet strength agent is continuously added to obtain the base paper. The base paper weight is controlled to be 15 g / m 2 , longitudinal dry strength 6 N / m, longitudinal wet tensile strength 0.5 N / m, base paper density 175 kg / m 3 ; Step 3: After the base paper obtained in step 2 is unwound through an unwinding frame, an unwound base paper is obtained, 20 parts of wet paper pulp and 1 part of a passivating agent are weighed and mixed, and then papermaking is performed in a vacuum rotary screen copying machine to obtain wet paper. The vacuum rotary screen copying machine includes a feeder, a guide roller 1, a guide roller 2, a guide roller 3, a traction roller, an upper pressure roller, a lower pressure roller, a support roller, a felt and a drying cylinder; Step 4: Weigh 3 portions of SAP and place them in the feeder. Control the SAP feed rate to 20 g / m 2 After starting the feeding, SAP will be dispersed on the surface of the wet paper. At the same time, the unwinding base paper is introduced into the upper and lower pressing rollers by the traction rollers, and is compounded and squeezed with the wet paper with SAP dispersed on the surface. Then, it is pressed, dried, wrinkled and rolled up by the rollers and drying cylinders to obtain ultra-thin absorbent paper.

[0032] The difference between Comparative Example 1 and Example 4 is that no passivating agent is added, and the rest is the same as Example 4.

[0033] Water absorption performance test 10.0 g (W0) of the ultrathin absorbent paper prepared in Examples 1-4 and Comparative Example 1 were respectively weighed, and the thickness of the ultrathin absorbent paper was measured using a vernier caliper, and then it was spread flat on the bottom of a 200-mesh sieve, and then completely immersed in 0.9% saline at 37°C. After 5 minutes, it was taken out and hung for 2 minutes, and the weight (W) of the ultrathin absorbent paper was weighed. According to the formula: water absorption rate = (W-W0) / W0, the water absorption rate of the ultrathin absorbent paper prepared in Examples 1-4 and Comparative Example 1 was calculated. The results are shown in Table 1.

[0034] Investigation of back infiltration Weigh 10.0 g of the ultrathin absorbent paper prepared in Examples 1-4 and Comparative Example 1 respectively, place them on a comprehensive liquid penetration tester, measure 40 mL of 0.9% saline and quickly pour it into the funnel. After 5 minutes of draining, place a sufficient amount of filter paper on the surface of the ultrathin absorbent paper, press a standard pressing block with a diameter of 100 mm and a mass of (1.2±0.002) kg, and start timing. After 1 minute, read the result to the nearest 0.01 g. Repeat the above operation 5 times, and take the average result. Figure 3 .

[0035] Table 1 Water absorption properties of ultra-thin absorbent paper

[0036] The results in Table 1 show that the ultra-thin absorbent paper prepared in Examples 1-4 has a water absorption rate of up to about 40 times when the thickness is less than 1 mm, which has a significant water absorption advantage compared with the water absorption rate of Comparative Example 1, indicating that the addition of the passivating agent can greatly improve the SAP "water grabbing" phenomenon.

[0037] Figure 2 The following is a simplified diagram of the production line based on the vacuum rotary screen copying machine in Examples 1-4 and Comparative Example 1. The unwinding base paper passes through guide rollers 1, 2 and traction rollers to reach the upper and lower pressure rollers. The wet paper is compounded with SAP on the felt through guide rollers 3, and then compounded and squeezed with the unwinding base paper through the upper and lower pressure rollers. It is pressed again at the drying cylinder and the support rollers, dried, wrinkled and rolled, and the ultra-thin absorbent paper is produced in one step.

[0038] Figure 3 The results of the back-infiltration amount show that when the amount of liquid added is below 80 mL, the back-infiltration amount of Examples 1-4 is relatively small. As the amount of liquid added increases, the back-infiltration amount increases. This is because when the physiological saline enters the ultra-thin absorbent paper, the good fiber state of the fluff pulp and coniferous pulp and a large number of hydrophilic groups easily produce capillary phenomena, allowing the physiological saline to diffuse better in the absorbent paper and be quickly absorbed by SAP. At the same time, the passivator reduces the "water-grabbing" ability of SAP, making it easier to lock in moisture.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0040] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A process for preparing ultra-thin absorbent paper, for preparing ultra-thin absorbent paper, characterized in that: The ultra-thin absorbent paper comprises the following raw materials in parts by weight: 15-35 parts of base paper pulp, 3-5.5 parts of SAP, 0.2-0.4 parts of wet strength agent, 0.8-1.2 parts of passivating agent and 20 parts of wet paper pulp; The preparation process of the ultra-thin absorbent paper specifically comprises the following steps: Step 1: weighing the base paper pulp and beating it to obtain the base paper for copying; Step 2: papermaking the base paper obtained in step 1, and adding a wet strength agent thereto to obtain base paper; Step 3: After the base paper obtained in step 2 is unwound, the unwound base paper is obtained, and wet paper pulp and a passivating agent are weighed, mixed, and paper-made to obtain wet paper; Step 4: Weigh the SAP blank, compound the unrolled base paper, SAP and wet paper, dry and roll them up to obtain ultra-thin absorbent paper.

2. The process for preparing ultrathin absorbent paper according to claim 1, characterized in that: In step 1, the base paper for copying has a beating degree of 15-18°SR and a wet weight of 19-21 g; In step 2, the papermaking process is carried out in a papermaking machine, and the base paper parameters are 15-35 g / m 2 , longitudinal dry strength 5-7 N / m, longitudinal wet tensile strength 0.3-0.5 N / m, density 175-177 kg / m 3 .

3. The process for preparing ultra-thin absorbent paper according to claim 1, characterized in that: The passivator is composed of the following raw materials in weight percentage: 50% SDBS, 25% TX-10 and 25% OP-10.

4. The process for preparing ultra-thin absorbent paper according to claim 1, characterized in that: The wet strength agent is selected from any one of PEI, UF ​​and PAE.

5. The process for preparing ultra-thin absorbent paper according to claim 1, characterized in that: The base paper pulp comprises the following raw materials in weight percentage: 40% fluff pulp and 60% coniferous wood pulp. The base paper pulp is prepared by crushing 40% fluff pulp and 60% coniferous wood pulp.

6. The process for preparing ultra-thin absorbent paper according to claim 1, characterized in that: The wet pulp comprises the following raw materials in weight percentage: 40% fluff pulp and 60% coniferous wood pulp. The preparation process of the wet pulp comprises the following steps: S1: Weigh fluff pulp and coniferous wood pulp and crush them to obtain wet paper pulp; S2: The wet paper stock obtained in step S1 is deflocculent to obtain wet paper pulp.

7. The process for preparing ultrathin absorbent paper according to claim 6, characterized in that: In step S2, the wet pulp has a beating degree of 13-15°SR and a wet weight of 23-24 g.

Images