JP2023182132A - Production method of cellulose fiber - Google Patents

Abstract

To provide a production method of cellulose fiber capable of reducing heating time.SOLUTION: A production method of cellulose fiber includes a web formation step of mixing fibrillated cellulose fiber and starch to form a web, a degassed water imparting step of imparting degassed water with a reduced content of dissolved air to the web, and a heating and compressing step of heating the web with the degassed water imparted in a compressed state in a mold by microwaves.SELECTED DRAWING: Figure 4

Description

The present invention relates to a method for manufacturing cellulose fibers.

BACKGROUND ART Conventionally, as shown in Patent Document 1, there has been known a sheet manufacturing apparatus that manufactures a sheet by mixing fibers and a binder. In this sheet manufacturing apparatus, a petroleum-derived resin is used as a binder.

JP 2019-131912 Publication

In recent years, it has been desired to use less petroleum as a binder in order to reduce the environmental impact.
In addition, for example, in a configuration in which a mixture containing fibers and a binder is heated while being pressed between upper and lower molds, there is a problem in that when the mixture becomes thick, it is necessary to heat the mixture sufficiently to the inside, which increases the heating time. .

The method for producing cellulose fibers includes a web forming step of mixing defibrated cellulose fibers and starch to form a web, and a degassing step of adding deaerated water with a reduced amount of dissolved air to the web. The method includes a step of applying air and water, and a heating/pressing step of heating the web with microwaves while putting the web to which the deaerated water has been applied into a mold and applying pressure to the web.

FIG. 1 is a schematic diagram showing the configuration of a cellulose fiber manufacturing apparatus according to a first embodiment. FIG. 2 is a schematic diagram showing the configuration of a heating/pressing section according to the first embodiment. FIG. 2 is a schematic diagram showing the configuration of a heating/pressing section according to the first embodiment. FIG. 1 is a schematic diagram showing the configuration of a cellulose fiber body according to the first embodiment. 1 is a flowchart showing a method for manufacturing a cellulose fiber body according to a first embodiment. FIG. 2 is a schematic diagram showing the configuration of a cellulose fiber manufacturing apparatus according to a second embodiment. 7 is a flowchart showing a method for manufacturing a cellulose fiber body according to a second embodiment.

1. First Embodiment First, the configuration of the cellulose fiber manufacturing apparatus 1 will be described. The cellulose fiber manufacturing apparatus 1 is an apparatus for manufacturing cellulose fibers S. The cellulose fiber body S of this embodiment is suitable for, for example, a mushroom culture medium.
As shown in FIG. 1, the cellulose fiber manufacturing apparatus 1 includes, for example, a coarse crushing section 10, a dry defibration section 20, a sorting section 30, a sorted material conveying section 40, a starch supply section 50, and a mixing/defibrating section 10. It includes a deposition section 60, a deaerated water application section 90, a cutting section 100, and a heating/pressure section 110. Furthermore, the cellulose fiber manufacturing apparatus 1 includes a control section (processor) that controls each of these sections.

The crushing section 10 shreds the supplied raw material in air such as the atmosphere to produce crushed materials. The shape and size of the crushed material are, for example, pieces of several cm square. The coarse crushing section 10 has a coarse crushing blade 14, and the coarse crushing blade 14 shreds the input raw material. As the coarse crushing section 10, for example, a shredder can be used. The crushed material shredded by the crushing section 10 is received by a hopper 16 and then transferred to a dry defibration section 20 via a pipe 17.
Here, the raw materials used in this embodiment include paper, cardboard, pulp, pulp sheet, sawdust, sawdust, wood, and the like.

The dry defibration section 20 dryly defibrates the crushed material (raw material) to produce cellulose fibers (also simply referred to as fibers). Here, processing such as defibration in air such as the atmosphere rather than in a liquid is referred to as a dry process. What has been defibrated in the dry defibrator 20 is also referred to as a defibrated product. As the dry defibration section 20, for example, an impeller mill is used. The dry defibration section 20 has a function of generating an airflow that sucks the raw material and discharges the defibrated material. Thereby, the dry defibration section 20 can suck the raw material from the inlet 22 along with the airflow using the airflow generated by itself, perform the defibration process, and transport the defibrated material to the discharge port 24 . The defibrated material that has passed through the dry defibration section 20 is transferred to the sorting section 30 via the pipe 28. Note that the airflow for conveying the defibrated material from the dry defibration unit 20 to the sorting unit 30 may be generated by using the airflow generated by the dry defibration unit 20, or by providing an airflow generating device such as a blower. Air currents may also be used.

The sorting section 30 introduces the defibrated material defibrated by the dry defibrating section 20 through an inlet 32 and sorts it according to the length of the fibers. The sorting section 30 includes a separation drum 31 and a housing section 33 that accommodates the separation drum 31. The separation drum 31 is for sorting fibers by fiber length, and uses, for example, a sieve. The separation drum 31 is a net and has a plurality of openings. Then, fibers or particles smaller than the opening size of the mesh, that is, the first sorting material passes through the mesh, and fibers or particles larger than the opening size of the mesh, undisintegrated pieces and lumps, that is, the second sorting material that does not pass through the mesh. You can separate things. The first sorted object is transferred to the sorted object transport section 40. The second sorted material is returned to the hopper 16 from the discharge port 34 via the pipe 36, and is again introduced into the dry defibration section 20. The separation drum 31 is a cylindrical sieve that is rotationally driven by a motor. As the mesh for the separation drum 31, for example, a wire mesh, expanded metal made by stretching a metal plate with cuts, or punched metal made by forming holes in a metal plate using a press or the like is used.

The sorted material transport section 40 deposits the first sorted material sorted by the sorting section 30 and transports it downstream. The sorted material conveying section 40 includes a mesh belt 46, a tension roller 47, and a suction mechanism 48.

The suction mechanism 48 can suck the first sorted material dispersed in the air by the separation drum 31 onto the mesh belt 46 . The first sort is deposited on the moving mesh belt 46.

The mesh belt 46 is stretched by a tension roller 47, and has a configuration that allows air to pass through it but not easily through the first sorted material. The mesh belt 46 moves as the tension roller 47 rotates. While the mesh belt 46 is continuously moving, the first sorted materials that have passed through the sorting section 30 are continuously piled up.

The suction mechanism 48 is provided below the mesh belt 46. The suction mechanism 48 can generate a downward airflow. The first sorted material dispersed in the air by the sorting section 30 can be sucked onto the mesh belt 46 by the suction mechanism 48 . Thereby, the discharge speed of the first sorted material discharged from the sorting section 30 can be increased.

The first sorted material deposited on the mesh belt 46 is conveyed downstream. The first sorted material is put into a hopper 55 arranged near the tension roller 47a located downstream in the conveyance path of the first sorted material of the mesh belt 46. The first sorted material placed in the hopper 55 is transferred to the mixing/depositing section 60 via the pipe 56.

A starch supply section 50 that supplies starch is arranged between the sorting section 30 and the mixing/deposition section 60. The starch supply unit 50 stores granular starch, and the starch is fed into the hopper 55 through the supply port 52 . As a result, the first sorted material and starch are transferred to the mixing/depositing section 60 via the pipe 56. Note that the first sorted material and starch may be transferred using a blower or the like.

Starch is a binder that binds cellulose fibers together. Starch gelatinizes when exposed to moisture and heat. The gelatinized starch binds the cellulose fibers together. Since starch is a natural binder, it can reduce environmental impact.

The mixing/deposition unit 60 introduces the first sorted material and starch from the inlet 72 and mixes the first sorted material (cellulose fibers) and starch to produce a mixture. The cellulose fibers contained in the mixture are then loosened and dispersed in the air as it falls. The mixing/deposition unit 60 deposits a mixture of the first sorted material and starch with good uniformity to form a web W.

The mixing/deposition section 60 has a deposition drum 71 and a housing section 73 that accommodates the deposition drum 71. The deposition drum 71 is a cylindrical sieve that is rotationally driven by a motor. As the deposition drum 71 rotates, the first sorted material and starch are mixed to produce a mixture. The deposition drum 71 is a net and has a plurality of openings. The deposition drum 71 allows fibers and starch with smaller mesh openings to pass through, and deposits the mixture.

Further, the mixing/depositing section 60 includes a mesh belt 82, a roller 84, and a suction mechanism 86. Mesh belt 82 is arranged below deposition drum 71 . The suction mechanism 86 can generate a downward airflow. The mixture dispersed in the air by the deposition drum 71 can be sucked onto the mesh belt 82 by the suction mechanism 86 . Thereby, the discharge speed of the mixture discharged from the deposition drum 71 can be increased. Furthermore, the suction mechanism 86 can form a downflow in the falling path of the mixture, and can prevent the fibers from becoming entangled with each other during falling. The mixture that has passed through the deposition drum 71 is deposited on the mesh belt 82 to form the web W.

The mesh belt 82 is an endless belt, and is stretched around a plurality of rollers 84. Due to the rotation of the rollers 84, the mesh belt 82 moves continuously, and the web W is conveyed downstream. The mesh belt 82 is made of, for example, metal, resin, cloth, nonwoven fabric, or the like. The surface of the mesh belt 82 is composed of a net lined with openings of a predetermined size. Among the cellulose fibers and particles falling from the stacking drum 71, fine particles with a size that can pass through the mesh fall below the mesh belt 82, and cellulose fibers and starch with a size that cannot pass through the mesh are on the mesh belt 82. The web W is formed by deposition. The web W is conveyed in the downstream direction as the mesh belt 82 moves.

A deaerated water applying section 90 is arranged downstream of the mesh belt 82 in the conveyance direction of the web W. The degassed water applying section 90 applies degassed water to the web W conveyed by the mesh belt 82. The degassed water applying unit 90 of this embodiment is arranged above the web W and applies degassed water to one side of the web W. The degassed water application unit 90 sprays degassed water as a mist, for example. Degassed water is water that has a reduced amount of dissolved air. For example, deaerated water is generated by removing air contained in water using a pump or the like. The amount of dissolved air in the degassed water is, for example, 6 mg/L or less. By applying deaerated water to the web W, it permeates while dissolving the air contained inside the web W. Thereby, the deaerated water can easily penetrate into the inside of the web W, and the entire web W can be uniformly moistened with water.

A cutting section 100 is arranged downstream of the degassed water applying section 90. The cutting unit 100 cuts the web W to which deaerated water has been applied. As a result, a cut web Wa is formed.

A heating/pressing section 110 is arranged downstream of the cutting section 100. The heating/pressing unit 110 heats the web Wa while applying pressure to form a cellulose fiber body S.
As shown in FIGS. 2A and 2B, the heating/pressing section 110 includes a mold 111, a microwave generator 115, and a frame 118 that accommodates the mold 111 and the microwave generator 115.

The mold 111 is made of resin. The mold 111 is made of polyolefin, for example. More specifically, it is formed from polymethylpentene. Note that the mold 111 may be made of fluororesin or silicone resin. Since these resins have a relatively large contact angle with respect to gelatinized starch, they can improve the releasability of the web Wa containing starch.

The mold 111 includes a first press mold 121 and a second press mold 122. The first press die 121 and the second press die 122 are configured to be able to press the web Wa. The first press mold 121 is arranged above the second press mold 122. The second press mold 122 is fixedly arranged. The first press die 121 is configured to be movable up and down relative to the second press die 122 by a driving force such as a motor. In the forming die 111, the first press die 121 is driven and controlled so as to apply a predetermined pressure to the web Wa.

In this embodiment, the press surface 121a of the first press die 121 that comes into contact with the web Wa has a flat surface. A press surface 122a of the second press die 122 that comes into contact with the web Wa has a flat surface. Furthermore, a plurality of drain holes 123 are formed in the second press die 122, penetrating from the press surface 122a in the thickness direction. The drain hole 123 is a hole through which water contained in the web Wa escapes. Specifically, when the web Wa is pressurized by the mold 111, water contained in the web Wa oozes out. The seeped moisture is discharged to the outside through the drain hole 123. Thereby, unnecessary moisture is removed and the web Wa can be heated efficiently.

The microwave generator 115 irradiates (oscillates) microwaves (for example, 1 GHz to 100 GHz) to heat the web Wa. Specifically, water molecules contained in the web Wa are vibrated by microwaves, and the web Wa is heated by the vibrations. In this embodiment, as shown in FIG. 2B, the web Wa to which deaerated water has been applied is placed in the mold 111, and while the web Wa is pressurized, the web Wa is heated with microwaves. For example, the web Wa is heated at about 80° C. to 100° C. for about 5 minutes.

The mold 111 and the microwave generator 115 are covered by a frame 118. The inside of the frame 118 is made of a metal member such as stainless steel. Thereby, the irradiated microwaves are reflected within the frame 118, so that the web Wa can be efficiently heated. Furthermore, leakage of microwaves to the outside of the frame 118 can be prevented.

Further, in the heating/pressing section 110 of the present embodiment, the web Wa can be heated with microwaves even when the web Wa is not pressurized. Specifically, the first press mold 121 is raised and microwaves are irradiated with the first press mold 121 not in contact with the web Wa, thereby heating the web Wa (for example, to about 100° C.). In this embodiment, the web Wa is dried by heating under pressure and then heating without applying pressure. Thereby, the web Wa is solidified and the cellulose fiber body S is formed. The cellulose fiber body S is in a state in which water is adsorbed to starch molecules (non-aging state). Starch also functions as a fertilizer and water retention agent. Such a cellulose fiber body S is suitable as a mushroom culture medium or the like.
The formed cellulose fiber body S is discharged into the receiving part 150. Since the mold 111 is made of resin, the cellulose fiber body S can be easily removed from the mold 111 and transported downstream.

Here, when the heating/pressing unit 110 heats the web Wa under a predetermined pressure, for example, a pressure to the extent that water in the web Wa oozes out, the surface of the web Wa becomes starch-free. It is heated while covered with melted water. Therefore, the starch component covering the surface of the web Wa solidifies. Then, as shown in FIG. 3, a coating (skin layer) Sa is formed on the surface of the molded cellulose fiber body S. The coating Sa has luster and can be distinguished from the appearance compared to a case without the coating Sa. By forming the coating Sa, generation of fine powder from inside the cellulose fiber body S can be suppressed. Thereby, adhesion of fine powder to products etc. around the cellulose fiber body S can be prevented.
In addition, since the starch is diluted by applying deaerated water by the deaerated water applicator 90, even if the amount of starch added is small, the surface of the web Wa can be easily covered with moisture containing starch, and a coating film can be formed. Sa can be easily formed.

In addition, when the cellulose fiber body S is used as a mushroom culture medium, the position and surface where mushrooms grow may be in a form without the coating Sa.
In this embodiment, since the drain hole 123 is formed in the second press die 122, the second press die 122 side is heated with more moisture than the first press die 121 side. Therefore, the coating Sa is easily formed on the web Wa surface (one surface of the cellulose fiber body S) that is in contact with the second press die 122. That is, by defining the arrangement position of the drain hole 123, the coating Sa can be formed at a desired position on the cellulose fiber body S.

Further, depending on the form of the mold 111, the coating Sa can be formed at a desired position. For example, the press surface 121a of the first press mold 121 is formed into a plurality of uneven shapes (microlens shape), and the press surface 122a of the second press mold 122 is formed into a flat surface. Thereby, the surface area of the press surface 121a becomes larger than the surface area of the press surface 122a, and the pressure applied to the web Wa of the first press mold 121 becomes smaller. On the other hand, since the pressure applied to the web Wa of the second press die 122 becomes larger, moisture tends to seep out to the second press die 122 side, making it easier to form a film Sa on the portion of the web Wa that is in contact with the press surface 122a. .
Further, by controlling the output of microwaves, it is possible to define the formation location of the coating Sa. For example, in the thickness direction of the web Wa, the output of the microwave is made larger for the side on which the coating Sa is desired to be formed. Thereby, the coating Sa can be formed in the portion where the microwave output is higher. Further, in addition to the first press die 121 side, the microwave generator 115 may be arranged on the second press die 122 side, and each microwave generator 115 may be controlled.
Further, in the cellulose fiber body S on which the coating Sa is formed, unnecessary portions of the coating Sa may be cut off with a cutter or the like.

In addition, in the cellulose fiber manufacturing apparatus 1 of this embodiment, the heating/pressing section 110 has an in-line configuration, but the invention is not limited to this. For example, the heating/pressing section 110 may be arranged separately to heat/press the cut web Wa.

Next, a method for manufacturing the cellulose fiber body S will be explained.
In addition, in this embodiment, the manufacturing method of the cellulose fiber body S by the cellulose fiber body manufacturing apparatus 1 is demonstrated.
As shown in FIG. 4, first, in a web forming step (step S11), defibrated cellulose fibers and starch are mixed to form a web W. Specifically, the raw material is defibrated in the dry defibration section 20 to generate cellulose fibers. Further, starch is supplied from the starch supply section 50 to the hopper 55. Then, in the mixing/deposition section 60, the cellulose fibers and starch are mixed and the mixed mixture is deposited on the mesh belt 82 to form the web W.

Next, in the deaerated water application step (step S12), deaerated water with a reduced amount of dissolved air is applied to the web W. Specifically, degassed water is sprayed onto the web W from the degassed water application section 90. The applied deaerated water easily penetrates into the web W while dissolving the air contained within the web W.

Next, in the room temperature pressing step (step S13), the web W is pressed at room temperature (for example, about 20° C. to 30° C.). Specifically, the cut web Wa cut by the cutting section 100 is put into a forming die 111 in the heating/pressing section 110, and the web Wa is subjected to multiple presses by the first press die 121 and the second press die 122. Press. Specifically, the first press mold 121 is moved up and down relative to the web Wa, and the pressurizing operation is repeated against the web Wa. At this time, the microwave generator 115 is not driven. By pressurizing the web Wa, the penetration of degassed water into the interior of the web Wa is promoted, and the degassed water penetrates the entire web Wa.

Next, in the heating and pressurizing step (step S14), the web Wa to which deaerated water has been applied is placed in the mold 111, and the web Wa is heated with microwaves while being pressurized. Specifically, the web Wa is pressurized by the first press mold 121 and the second press mold 122 of the heating/pressing section 110, and microwaves are irradiated.
Further, in the heating/pressurizing step, pressurization and non-pressurization are performed multiple times. Specifically, the first press die 121 is repeatedly moved up and down relative to the second press die 122 while being irradiated with microwaves. As a result, the pressing operation and non-pressing operation on the web Wa are repeatedly performed. By repeating the pressurizing operation and the non-pressurizing operation, the deaerated water is encouraged to penetrate into the web Wa, and the moisture contained in the web Wa is also encouraged to seep out.
Since the web Wa is heated in a state in which water has oozed out onto the surface thereof, the starch component contained in the water is solidified, and a film Sa is formed on the surface of the web Wa.
Moreover, since the first press mold 121 and the second press mold 122 are made of resin, they have high mold releasability with respect to the web Wa containing starch. Therefore, even during heating, a pressurizing operation and a non-pressurizing operation can be easily performed.

Next, in the drying step (step S15), the web Wa is heated again using microwaves to dry the web Wa. Specifically, after the heating and pressurizing step (step S14), the first press die 121 is raised, thereby separating the first press die 121 from the web Wa. Then, the web Wa is dried by irradiating microwaves. As a result, cellulose fibers S in a state in which water is adsorbed to starch molecules (non-aging state) are formed.

As described above, according to the present embodiment, since the web Wa is heated with microwaves, even if the web Wa becomes thick, the inside of the web Wa can be quickly heated, and the heating time can be shortened. For example, conventionally, in a configuration in which the web Wa is heated and pressurized using upper and lower molds, the molding time takes about 60 to 90 minutes. On the other hand, in this embodiment, it takes about 5 minutes to mold the same thickness.

2. Second Embodiment Next, a second embodiment will be described. Note that the same configurations as in the first embodiment are given the same reference numerals and redundant explanations will be omitted.
The cellulose fiber manufacturing apparatus 1A of this embodiment is, for example, an apparatus for manufacturing cellulose fiber S suitable for cushioning materials and packaging materials.

As shown in FIG. 5, the cellulose fiber manufacturing apparatus 1A of the present embodiment includes, for example, a coarse crushing section 10, a dry defibration section 20, a sorting section 30, a sorted material conveying section 40, and a starch supply section 50. , a mixing/depositing section 60 , a deaerated water applying section 90 , a cutting section 100 , a heating/pressurizing section 110 , and a cooling section 140 . Furthermore, the cellulose fiber manufacturing apparatus 1A includes a control section (processor) that controls each of these sections.
Note that the configuration of the cellulose fiber manufacturing apparatus 1A other than the cooling unit 140 is the same as that of the first embodiment, so a description thereof will be omitted.

The cooling section 140 is arranged downstream of the heating/pressurizing section 110. The cooling unit 140 cools the web Wa processed by the heating/pressing unit 110. The cooling unit 140 is configured to be able to cool the web Wa at 25° C. or lower. Cooling unit 140 is, for example, a refrigerator. The cooling unit 140 removes water contained in the web Wa and bonds (aging) starch molecules. Thereby, a cellulose fiber body S is formed. Note that the cooling unit 140 may not have an in-line configuration but may have a separately arranged configuration.

Next, a method for manufacturing the cellulose fiber body S will be explained.
In addition, in this embodiment, the manufacturing method of the cellulose fiber body S by 1 A of cellulose fiber body manufacturing apparatuses is demonstrated.
As shown in FIG. 6, the method for manufacturing cellulose fibers S includes a web forming step (step S21), a deaerated water application step (step S22), a room temperature pressing step (step S23), and a heating/pressing step (step S24). ), and the cooling step (step S25) are executed in this order.
Note that the web forming process (step S21) to the heating/pressing process (step S24) are the same as the web forming process (step S11) to the heating/pressing process (step S14) in the first embodiment, so a description thereof will be omitted. .

The cooling process (step S25) cools the web Wa after the heating and pressurizing process (step S24). Specifically, the web Wa is cooled by the cooling unit 140 in an environment of 25° C. or lower. For example, the web Wa is cooled by the cooling unit 140 in an environment of 5° C. for 72 hours. This removes the water contained in starch, causing starch molecules to bond with each other and become stale. Through the above steps, the cellulose fiber body S is formed.

As described above, according to the present embodiment, the web Wa is cooled after being heated and pressurized. As a result, the starch in the web Wa ages and cellulose fibers S are formed. The cellulose fiber body S thus formed has moisture absorption resistance. Therefore, the cellulose fiber body S can be used as a cushioning material, a packaging material, etc., for example. Moreover, since the coating Sa is formed on the surface of the cellulose fiber body S, generation of fine powder can be suppressed. Thereby, when used as a cushioning material or packaging material, adhesion of fine powder to products etc. can be suppressed.

In addition, in the cellulose fiber body manufacturing apparatus 1A, the cellulose fiber body S can be molded into any shape. In this case, for example, the shapes of the first press mold 121 and the second press mold 122 of the mold 111 in the heating/pressing section 110 are set as appropriate. Thereby, a cellulose fiber body S having portions with different thickness dimensions or a cellulose fiber body S having an uneven shape can be formed. Thereby, the cellulose fiber body S can be formed to correspond to the shape of the product to be packed.

3. Example Next, an example will be described.

3-1. Example 1
1) Using the dry defibration section 20, 150 g of defibrated cellulose fibers were produced.
2) Cellulose fibers and 50 g of starch (SK200, manufactured by Nippon Cornstarch Co., Ltd.) were mixed using the mixing/depositing section 60 to form a web W.
3) Degassed water (dissolved air amount: 6 mg/L, 8 g) was sprayed onto the web W using the degassed water application unit 90.
4) Using the heating/pressing unit 110, the web Wa was heated by irradiating microwaves while the web Wa was being pressurized by the mold 111. The material of the mold 111 was polymethylpentene. Further, a plurality of drain holes 123 were formed in the second press die 122. The heating conditions in the microwave generator 115 are 200W, 85° C., and 5 Min. Met.
5) Using the cooling unit 140, the web Wa was cooled to form a cellulose fiber body S. The cooling conditions were 5°C and 72 hours. Met.

3-2. Example 2
1) Using the dry defibration section 20, 150 g of defibrated cellulose fibers were produced.
2) The cellulose fibers and 50 g of starch (SK200 manufactured by Nippon Cornstarch Co., Ltd.) were mixed using the mixing/depositing section 60 to form a web W.
3) Degassed water (dissolved air amount: 6 mg/L, 8 g) was sprayed onto the web W using the degassed water application unit 90.
4) Using the heating/pressing unit 110, the web Wa was heated by irradiating microwaves while the web Wa was being pressurized by the mold 111. The material of the mold 111 was polymethylpentene. Further, a plurality of drain holes 123 were formed in the second press die 122. The heating conditions in the microwave generator 115 are 200W, 85° C., and 5 Min. Met.
5) Thereafter, the first press die 121 was raised, and microwaves were irradiated with the first press die 121 separated from the web Wa to dry the web Wa and form the cellulose fiber body S. The drying conditions in the microwave generator 115 are 500W, 100°C, and 5Min. Met.

3-3. Example 3
1) The same steps as in Example 2 were carried out to form two cellulose fiber bodies.
2) Using the deaerated water application unit 90, deaerated water (dissolved air amount: 6 mg/L, 8 g) was sprayed onto one side of each cellulose fiber body in 1).
3) 2) The two cellulose fiber bodies were put into the mold 111 in a stacked state with the surfaces of each cellulose fiber body sprayed with deaerated water in contact with each other. Then, the two cellulose fiber bodies were irradiated with microwaves and heated while being pressed with the mold 111. The material of the mold 111 was polymethylpentene. Further, a plurality of drain holes 123 were formed in the second press die 122. The heating conditions in the microwave generator 115 are 200W, 85° C., and 5 Min. Met.
4) Using the cooling unit 140, the cellulose fiber body was cooled to form one cellulose fiber body S. The cooling conditions were 5°C and 72 hours. Met.

3-4. Example 4
1) In Example 2, two cellulose fibers were formed.
2) Degassed water (dissolved air amount: 6 mg/L, 8 g) was sprayed onto one side of each cellulose fiber body S in 1) using the degassed water application unit 90.
3) 2) The two cellulose fiber bodies were put into the mold 111 in a stacked state with the surfaces of each cellulose fiber body sprayed with deaerated water in contact with each other. Then, the two cellulose fiber bodies were irradiated with microwaves and heated while being pressed with the mold 111. The material of the mold 111 was polymethylpentene. Further, a plurality of drain holes 123 were formed in the second press die 122. The heating conditions in the microwave generator 115 are 200W, 85° C., and 5 Min. Met.
4) Thereafter, the first press mold 121 was raised, and microwaves were irradiated with the first press mold 121 separated from the cellulose fiber body to dry the cellulose fiber body and form one cellulose fiber body S. The drying conditions in the microwave generator 115 are 500W, 100°C, and 5Min. Met.

3-5. Example 5
1) In each of Examples 1 to 4 above, before heating and pressurizing, the heating and pressurizing section 110 is used to perform two pressurizing operations on the web Wa or the cellulose fiber body at room temperature (25° C.). Repeated times.

3-6. Example 6
1) In each of Examples 1 to 4 above, cellulose fibers S having portions with different thickness dimensions were formed. Specifically, three types of molds 111 with different shapes were prepared. Heating and pressurization were performed using each mold 111 to form three types of cellulose fiber bodies S in each example. The differences between the thinnest dimension and the thickest dimension of the cellulose fiber body S were 3 mm, 10 mm, and 30 mm.

3-7. Evaluation method 1) Moisture absorption resistance was evaluated using the following procedure.
2) The cellulose fiber bodies S formed in each example were dried, and the weight of each cellulose fiber body S was measured.
3) Thereafter, each cellulose fiber body S was left in a constant temperature and humidity bath. Moisture absorption conditions were 60°C, 90% RH, 72 hours. Met.
4) The weight of each cellulose fiber body S after moisture absorption was measured.
5) The difference in weight before and after moisture absorption was measured.
6) Evaluation item: presence or absence of weight change before and after moisture absorption. Presence or absence of deformation of the shape of the cellulose fiber body S.

3-8. Evaluation results 1) In the examples in which the cooling process was performed in Examples 1, 3, and 5, and in the example in which the cooling process was performed in Example 6, there was no change in weight before and after moisture absorption. Further, there was no deformation of the cellulose fiber body S.
2) In Examples other than the above, the weight increased by about 20% after moisture absorption, but the cellulose fiber body S did not deform.

3-9. Summary 1) Each cellulose fiber body S formed in the example in which the cooling process was performed in Example 1, Example 3, and Example 5, and the example in which the cooling process was performed in Example 6, has a weight before and after moisture absorption. It was found that there was no change in the properties of the material, and that it could be used as a cushioning material or packaging material.
Furthermore, even if the thickness of the cellulose fiber S formed by performing the cooling process in Example 6 is not uniform, there is no change in weight before and after absorbing moisture, and it can be used as a packaging material that matches the shape of the item to be packed. It turns out it's possible.
2) It was found that the cellulose fibers S formed in Examples other than the above can be applied as, for example, a mushroom culture medium, since the cellulose fibers S are formed to be able to absorb moisture while maintaining their shape.

DESCRIPTION OF SYMBOLS 1,1A...Cellulose fiber manufacturing apparatus, 10...Crushing part, 14...Crushing blade, 16...Hopper, 17...Pipe, 20...Dry defibration part, 22...Inlet, 24...Outlet, 28...Pipe , 30... Sorting section, 31... Separation drum, 32... Inlet, 33... Housing section, 34... Discharge port, 36... Pipe, 40... Sorted material conveying section, 46... Mesh belt, 47... Tension roller, 47a... Tension roller, 48... Suction mechanism, 50... Starch supply section, 52... Supply port, 55... Hopper, 56... Pipe, 60... Mixing/deposition section, 71... Deposition drum, 72... Inlet, 73... Housing section, 82... Mesh belt, 84... Roller, 86... Suction mechanism, 90... Deaerated water application section, 100... Cutting section, 110... Heating/pressing section, 111... Molding mold, 115... Microwave generating section, 118... Frame body, 121...first press mold, 121a...press surface, 122...second press mold, 122a...press surface, 123...drain hole, 140...cooling section, 150...receiving section, S...cellulose fiber body, Sa... Coating, W, Wa...web.

Claims (5)

A method for producing a cellulose fibrous body, the method comprising:
a web forming step of mixing defibrated cellulose fibers and starch to form a web;
a deaerated water applying step of applying deaerated water with a reduced amount of dissolved air to the web;
A method for producing a cellulose fiber body, comprising a heating and pressurizing step of heating the web with microwaves in a state in which the web to which the deaerated water has been applied is placed in a mold and the web is pressurized. A method for producing a cellulose fiber body according to claim 1, comprising:
The method for producing a cellulose fiber body, wherein the mold in the heating and pressurizing step is made of resin. A method for producing a cellulose fiber body according to claim 2, comprising:
The mold in the heating and pressurizing step includes a first press mold and a second press mold that presses the web together with the first press mold,
Among the first press mold and the second press mold, one of the press molds has a flat press surface, and the other press mold has drain holes for releasing moisture contained in the web, a cellulose fiber body. manufacturing method. A method for producing a cellulose fiber body according to claim 1, comprising:
A method for producing a cellulose fiber body, which comprises a drying step of heating the web again with microwaves to dry the web after the heating and pressurizing step. A method for producing a cellulose fiber body according to claim 1, comprising:
A method for producing a cellulose fiber body, comprising a cooling step of cooling the web after the heating and pressurizing step.

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