Fiber body manufacturing method

Abstract

To suppress sticking of a web to a compression roller, etc.SOLUTION: A fiber body manufacturing method includes a deposition step of forming a web by depositing material, which contains fibers, starch or dextrin, on a first conveyor belt in a dry process, a conveyance step of peeling off a first face of the web from the first conveyor belt and then bringing a second face of the web, which is an opposite face of the first face peeled off from the first conveyor belt, into contact with a second conveyor belt to convey the web, a moisture application step of applying moisture to the web in contact with the first conveyor belt or the second conveyor belt, and a heating step of bringing the web peeled off from the second conveyor belt into contact with a heating section to heat the web and then binding the fibers with the starch or the dextrin to form a fiber body. The web peeled off from the second conveyor belt is directly supplied to the heating section.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for producing a fibrous body. [Background technology]

[0002] Conventionally, as shown in Patent Document 1, there is known a sheet manufacturing apparatus that includes a first conveying section having a first conveying belt that conveys a fiber-containing web, a second conveying section having a second conveying belt that conveys the web while sucking the web in a direction away from the first conveying belt, a pressure roller that is arranged downstream of the second conveying section in the web conveying direction and pressurizes the web, and a heating roller that is arranged downstream of the pressure section in the web conveying direction and heats the web. Furthermore, Patent Document 1 discloses spraying water to which starch or PVA (polyvinyl alcohol) has been added onto a web. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-168904 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned device, when water to which starch or PVA (polyvinyl alcohol) has been added is sprayed onto a web, there is a problem in that the web sticks to the pressure roller or the like due to the adhesive force of the starch or the like. If the web sticks to the pressure roller or the like, this can cause problems with the web being conveyed and damage to the web. [Means for solving the problem]

[0005] The fibrous body manufacturing method is a fibrous body manufacturing apparatus including a deposition section that forms a web on a first conveyor belt, a conveyor section having a second conveyor belt that conveys the web, a moisture imparting section that imparts moisture to the web, and a heating section that heats the web to which moisture has been imparted, and includes a deposition step of dry-depositing a material containing fibers and starch or dextrin on the first conveyor belt to form the web, a conveying step of peeling a first surface of the web from the first conveyor belt and contacting a second surface of the web, which is the surface opposite to the first surface peeled from the first conveyor belt, with the second conveyor belt to convey the web, a moisture imparting step of imparting the moisture to the web in contact with the first conveyor belt or the second conveyor belt, and a heating step of bringing the heating section into contact with the web peeled from the second conveyor belt to heat the web and bond the fibers together with the starch or the dextrin to form a fibrous body, and the web peeled from the second conveyor belt is directly supplied to the heating section. [Brief description of the drawings]

[0006] [Figure 1] FIG. 2 is a schematic diagram showing the configuration of a fibrous body manufacturing apparatus. [Diagram 2] FIG. 2 is a partially enlarged view showing the configuration of a fibrous body manufacturing apparatus. [Diagram 3] 4 is a flowchart showing a method for producing a fibrous body. [Figure 4] 10 is a flowchart showing another method for producing a fibrous body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] 1. First embodiment First, the configuration of the fibrous material manufacturing apparatus 100 will be described, and then the fibrous material manufacturing method will be described.

[0008] The fibrous body manufacturing apparatus 100 is an apparatus for manufacturing a sheet-like fibrous body S. As shown in Fig. 1, the fibrous body manufacturing apparatus 100 includes, for example, a supply section 10, a crushing section 12, a defibrating section 20, a sorting section 40, a first web forming section 45, a rotating body 49, a mixing section 50, a depositing section 60, a second web forming section 70, a conveying section 78, a moisture providing section 79, a heating section 80, and a cutting section 90.

[0009] The supply unit 10 supplies raw material to the crushing unit 12. The supply unit 10 is, for example, an automatic input unit for continuously inputting raw material to the crushing unit 12. The raw material supplied by the supply unit 10 is a material containing various fibers.

[0010] The fibers are not particularly limited, and a wide variety of fiber materials can be used. Examples of the fibers include natural fibers (animal fibers, plant fibers), chemical fibers (organic fibers, inorganic fibers, organic-inorganic composite fibers), and the like. More specifically, the fibers include fibers made of cellulose, silk, wool, cotton, hemp, kenaf, flax, ramie, jute, Manila hemp, sisal, coniferous trees, broadleaf trees, and the like, and these may be used alone or in appropriate mixtures, or may be used as regenerated fibers that have been purified, etc.

[0011] Examples of the raw material of the fiber include pulp, waste paper, and old cloth. The fiber may be subjected to various surface treatments. The material of the fiber may be a pure substance, or may be a material containing multiple components such as impurities and other components. The fiber may be a defibrated material obtained by dry defibration of waste paper, pulp sheets, and the like.

[0012] The length of the fiber is not particularly limited, but the length of a single independent fiber along the longitudinal direction is 1 μm or more and 5 mm or less, preferably 2 μm or more and 3 mm or less, and more preferably 3 μm or more and 2 mm or less.

[0013] In the fibrous body manufacturing apparatus 100, moisture is added in the moisture adding section 79, so if a fiber capable of forming hydrogen bonds is used, the mechanical strength of the formed fibrous body S can be increased. An example of such a fiber is cellulose.

[0014] The fiber content in the fibrous material S is, for example, 50% by mass or more and 99.9% by mass or less, preferably 60% by mass or more and 99% by mass or less, and more preferably 70% by mass or more and 99% by mass or less. Such a content can be achieved by blending when forming the mixture.

[0015] The crushing unit 12 cuts the raw material supplied by the supply unit 10 into small pieces in air, such as the atmosphere. The small pieces have a shape and size of, for example, several centimeters square. In the example shown in the figure, the crushing unit 12 has crushing blades 14, which can cut the input raw material. For example, a shredder is used as the crushing unit 12. The raw material cut by the crushing unit 12 is received in a hopper 1 and then transferred to the defibrating unit 20 via a pipe 2.

[0016] The defibrating unit 20 defibrates the raw material cut by the coarse crushing unit 12. Here, "defibrating" refers to unraveling the raw material, which is made up of multiple fibers bound together, into individual fibers. The defibrating unit 20 also has the function of separating substances such as resin particles, ink, toner, and anti-bleeding agents attached to the raw material from the fibers.

[0017] The material that has passed through the defibration unit 20 is called the "defibrated material." In addition to the defibrated material fibers, the "defibrated material" may also contain additives such as resin particles that have separated from the fibers when the fibers are defibrated, coloring agents such as ink and toner, and anti-bleeding agents and paper strength enhancers. The defibrated material has a string-like shape. The defibrated material may exist in a state where it is not entangled with other defibrated fibers, i.e., in an independent state, or it may exist in a state where it is entangled with other defibrated material and forms a lump, i.e., in a state where it forms lumps.

[0018] The defibrator unit 20 performs defibration in a dry manner. Here, the term "dry manner" refers to performing defibration and other processes in air, such as in the atmosphere, rather than in a liquid. For example, an impeller mill is used as the defibrator unit 20. The defibrator unit 20 has a function of generating an airflow that sucks in the raw material and discharges the defibrated material. This allows the defibrator unit 20 to suck in the raw material together with the airflow from the inlet 22 using the airflow it generates, defibrate the raw material, and transport the defibrated material to the outlet 24. The defibrated material that has passed through the defibrator unit 20 is transferred to the sorting unit 40 via the pipe 3. The airflow for transporting the defibrated material from the defibrator unit 20 to the sorting unit 40 may be the airflow generated by the defibrator unit 20, or an airflow generating device such as a blower may be provided and the airflow may be used.

[0019] The sorting unit 40 introduces the defibrated material defibrated by the defibration unit 20 from an inlet 42 and sorts it according to the length of the fibers. The sorting unit 40 has, for example, a drum unit 41 and a housing unit 43 that houses the drum unit 41. For example, a sieve is used as the drum unit 41. The drum unit 41 has a net and can separate fibers or particles smaller than the size of the mesh of the net, i.e., a first sorted material that passes through the net, from fibers, undefibrated pieces, and lumps larger than the size of the mesh of the net, i.e., a second sorted material that does not pass through the net. For example, the first sorted material is transferred to the deposition unit 60 via a pipe 7. The second sorted material is returned to the defibration unit 20 from the discharge port 44 via a pipe 8. Specifically, the drum unit 41 is a cylindrical sieve that is rotated by a motor. The mesh of the drum portion 41 may be, for example, a wire mesh, an expanded metal made by stretching a metal plate with slits, or a punched metal made by forming holes in a metal plate using a press or the like.

[0020] The first web forming unit 45 conveys the first sorted material that has passed through the sorting unit 40 to the pipe 7. The first web forming unit 45 has, for example, a mesh belt 46, a tension roller 47, and a suction mechanism 48.

[0021] The suction mechanism 48 can suck the first sorted material, which has passed through the openings of the sorting unit 40 and been dispersed in the air, onto the mesh belt 46. The first sorted material is deposited on the moving mesh belt 46 and forms a web V.

[0022] Materials that have passed through the openings of the sorting section 40 are accumulated on the mesh belt 46. The mesh belt 46 is stretched by tension rollers 47 and is configured to prevent materials from passing through but allow air to pass through. The mesh belt 46 moves as the tension rollers 47 rotate. Materials that have passed through the sorting section 40 continuously fall and accumulate on the mesh belt 46 as the mesh belt 46 moves continuously, forming a web V on the mesh belt 46.

[0023] The suction mechanism 48 is provided below the mesh belt 46. The suction mechanism 48 can generate a downward airflow. The suction mechanism 48 can suck the passing materials dispersed in the air by the sorting section 40 onto the mesh belt 46. This can increase the discharge speed from the sorting section 40.

[0024] The web V is formed into a soft and puffy state containing a lot of air by passing through the screening unit 40 and the first web forming unit 45. The web V accumulated on the mesh belt 46 is input into the pipe 7 and transported to the accumulation unit 60.

[0025] The rotating body 49 can cut the web V. In the illustrated example, the rotating body 49 has a base 49a and protrusions 49b protruding from the base 49a. The protrusions 49b have, for example, a plate-like shape. In the illustrated example, four protrusions 49b are provided, and the four protrusions 49b are provided at equal intervals. By rotating the base 49a in the direction R, the protrusions 49b can rotate around the base 49a as an axis. By cutting the web V with the rotating body 49, for example, it is possible to reduce the fluctuation in the amount of defibrated material supplied per unit time to the deposition section 60.

[0026] The rotating body 49 is provided in the vicinity of the first web forming section 45. In the illustrated example, the rotating body 49 is provided in the vicinity of the tension roller 47a located downstream in the path of the web V. The rotating body 49 is provided at a position where the protrusions 49b can contact the web V but do not contact the mesh belt 46 on which the web V is deposited. This makes it possible to prevent the mesh belt 46 from being worn by the protrusions 49b. The shortest distance between the protrusions 49b and the mesh belt 46 is, for example, 0.05 mm or more and 0.5 mm or less. This is the distance at which the web V can be cut without damaging the mesh belt 46.

[0027] The mixing section 50 mixes, for example, the first sorted material that has passed through the sorting section 40 with a binder. The mixing section 50 has, for example, a binder supplying section 52 that supplies the binder, a pipe 54 that transports the first sorted material and the binder, and a blower 56. In the example shown in the figure, the binder is supplied from the binder supplying section 52 to the pipe 54 via a hopper 9. The pipe 54 is continuous with the pipe 7.

[0028] In the mixing section 50, an air flow is generated by a blower 56, and the first sorted material and the binder can be transported while being mixed in the pipe 54. The mechanism for mixing the first sorted material and the binder is not particularly limited, and may be one that mixes with blades that rotate at high speed, or one that utilizes the rotation of a container such as a V-type mixer.

[0029] The binder supplying section 52 may be a screw feeder, a disk feeder, or the like.

[0030] The binder supplied from the binder supply unit 52 is starch or dextrin. Starch is a polymer in which multiple α-glucose molecules are polymerized through glycosidic bonds. Starch may be linear or may contain branches.

[0031] Starch derived from various plants can be used. Examples of starch sources include cereals such as corn, wheat, and rice, beans such as broad beans, mung beans, and red beans, tubers such as potato, sweet potato, and tapioca, wild plants such as dogtooth violets, bracken, and kudzu, and palms such as sago palm.

[0032] In addition, processed starch or modified starch may be used as the starch. Examples of the processed starch include acetylated adipic acid cross-linked starch, acetylated starch, oxidized starch, sodium octenyl succinate starch, hydroxypropyl starch, hydroxypropylated phosphate cross-linked starch, phosphorylated starch, phosphate esterified phosphate cross-linked starch, urea phosphate esterified starch, sodium starch glycolate, and high amylose corn starch. In addition, dextrin obtained by processing or modifying starch can be suitably used as the modified starch.

[0033] In the fibrous body manufacturing apparatus 100, by using starch or dextrin, the addition of moisture and then pressurizing and heating causes at least one of gelatinization and hydrogen bonding between the fibers, thereby giving the fibrous body S sufficient strength.

[0034] The starch or dextrin content in the fibrous material S is, for example, 0.1% by mass or more and 50% by mass or less, preferably 1% by mass or more and 40% by mass or less, and more preferably 1% by mass or more and 30% by mass or less. Such a content can be achieved by blending when forming the mixture.

[0035] In addition to the binder, the binder supplying section 52 may contain, depending on the type of fibrous body S to be manufactured, a coloring agent for coloring the fibers, an aggregation inhibitor for inhibiting aggregation of the fibers and the binder, and a flame retardant for making the fibers, etc., less flammable. The mixture that has passed through the mixing section 50 is transferred to the deposition section 60 via a pipe 54.

[0036] The depositing unit 60 introduces the mixture that has passed through the mixing unit 50 from an inlet 62, loosens the tangled defibrated material, and drops it while dispersing it in the air. This allows the depositing unit 60 to deposit the mixture (a material containing fibers and a binder) in the second web forming unit 70 with good uniformity.

[0037] The deposition section 60 has, for example, a drum section 61 and a housing section 63 that houses the drum section 61. A rotating cylindrical sieve is used as the drum section 61. The drum section 61 has a mesh and causes fibers or particles smaller than the mesh size contained in the mixture that has passed through the mixing section 50 to fall. The configuration of the drum section 61 is the same as that of the drum section 41, for example.

[0038] The "sieve" of the drum unit 61 does not have to have the function of separating out a specific object. In other words, the "sieve" used as the drum unit 61 means one equipped with a net, and the drum unit 61 may allow all of the mixture introduced into the drum unit 61 to fall.

[0039] The second web forming section 70 accumulates the material that has passed through the accumulation section 60 to form a web W. The second web forming section 70 has, for example, a first mesh belt 72 as a first conveyor belt, a tension roller 74, and a suction mechanism 76.

[0040] Materials passing through the openings of the deposition section 60 are deposited on the first mesh belt 72. The first mesh belt 72 is stretched by tension rollers 74 and is configured to prevent materials from passing through but allow air to pass through. The first mesh belt 72 moves as the tension rollers 74 rotate. Materials passing through the deposition section 60 are continuously deposited on the first mesh belt 72 as the first mesh belt 72 moves continuously, forming a web W on the first mesh belt 72.

[0041] The suction mechanism 76 is provided below the first mesh belt 72. The suction mechanism 76 can generate a downward airflow. The suction mechanism 76 can suck the mixture dispersed in the air by the deposition unit 60 onto the first mesh belt 72. This can increase the discharge speed from the deposition unit 60. Furthermore, the suction mechanism 76 can form a downflow in the falling path of the mixture, preventing the defibrated material and the binder from becoming entangled during the fall.

[0042] As described above, by passing through the deposition unit 60 and the second web forming unit 70, the web W is formed in a soft and puffy state containing a lot of air.

[0043] A conveying section 78 is disposed downstream in the conveying direction of the web W on the first mesh belt 72. The conveying section 78 peels off the web W on the first mesh belt 72 from the first mesh belt 72 and conveys it toward the heating section 80. As shown in FIG. 2, the conveying section 78 has a second mesh belt 78a as a second conveying belt, a roller 78b, and a suction mechanism 78c. The second mesh belt 78a is stretched by the roller 78b and configured to pass air. The second mesh belt 78a is configured to be movable by the rotation of the roller 78b. The suction mechanism 78c is disposed at a position facing the web W across the second mesh belt 78a. The suction mechanism 78c has a blower and generates an upward airflow on the second mesh belt 78a by the suction force of the blower. The web W is sucked by this airflow.

[0044] As a result, the first surface Wa of the web W is peeled off from the first mesh belt 72, and the second surface Wb, which is the surface opposite to the first surface Wa peeled off from the first mesh belt 72, can be adsorbed onto the second mesh belt 78a. The web W adsorbed onto the second mesh belt 78a is transported in a state of contact with the second mesh belt 78a.

[0045] A moisture applying section 79 is disposed downstream of the accumulation section 60. The moisture applying section 79 applies moisture to the web W in contact with the first mesh belt 72 or the second mesh belt 78a. The moisture applicator 79 of this embodiment is disposed below the conveyor 78, and applies moisture to the web W in contact with the second mesh belt 78a. In detail, the moisture applicator 79 applies moisture toward the first surface Wa of the web W in contact with the second mesh belt 78a. That is, in this embodiment, moisture is applied from below the web W toward the first surface Wa. The moisture applicator 79 applies moisture to the web W in the form of, for example, water vapor or mist. This allows moisture to be applied uniformly to the web W.

[0046] The moisture applying unit 79 of this embodiment includes a container 79a capable of storing water, and a piezoelectric vibrator 79b disposed at the bottom of the container 79a. The top of the container 79a is open, and the container 79a is disposed so that the opening faces the first surface Wa of the web W. By driving the piezoelectric vibrator 79b, ultrasonic waves are generated in the water, and mist is generated in the container 79a. The generated mist is supplied to the web W through the opening of the container 79a. By applying moisture from below the web W, water droplets do not fall onto the web W even if condensation occurs on or near the moisture applying unit 79.

[0047] Further, the suction mechanism 78c of the conveying section 78 is disposed at a position facing the moisture providing section 79 across the second mesh belt 78a. This allows the moisture-containing airflow generated in the moisture providing section 79 by the suction mechanism 78c to pass through the inside of the web W, and moisture can be provided to the inside of the web W. That is, the suction mechanism 78c is disposed facing a part of the first mesh belt 72 of the second web forming section 70 and the container 79a of the moisture providing section 79. This allows the common suction mechanism 78c to perform both the function of peeling the web W from the first mesh belt 72 and adsorbing it to the second mesh belt 78a, and the function of providing moisture to the inside of the web W. This allows the configuration of the fibrous body manufacturing apparatus 100 to be simplified.

[0048] In this embodiment, moisture is applied from the first surface Wa side of the web W, which is opposite to the second surface Wb of the web W in contact with the second mesh belt 78a, so that the second surface Wb side can be transported with weaker adhesive strength than the first surface Wa side. This makes it possible to prevent the moisture-applied web W from sticking to the second mesh belt 78a.

[0049] Furthermore, the moisture applied from the moisture application unit 79 does not contain starch or dextrin. Therefore, the web W can be transported in a state in which the binding strength of starch or the like is not fully exerted, and the web W can be prevented from sticking to members such as the second mesh belt 78a. The moisture content of the web W to which moisture has been added in the moisture adding section 79 is 12% by mass or more and 40% by mass or less. The specified web moisture content allows hydrogen bonds to be effectively formed between the fibers, and the strength of the fibrous body S to be increased. In addition, the specified web moisture content allows the web W to be prevented from sticking to the second mesh belt 78a. Furthermore, by specifying the moisture content of the web W to be 40% by mass or less, the amount of water used can be reduced. Furthermore, even if the web W contains a binder (starch or dextrin), the web W is prevented from sticking to the second mesh belt 78a, and the bonding strength between the fibers is increased, thereby increasing the strength of the fibrous body S.

[0050] A heating section 80 is disposed downstream of the conveying section 78 and the moisture imparting section 79. The web W to which moisture has been imparted is conveyed to the heating section 80.

[0051] The heating section 80 heats the web W to which moisture has been added and which has been peeled off from the second mesh belt 78a. The heating section 80 of this embodiment heats the web W to which moisture has been added and pressurizes it at the same time. As a result, the moisture contained in the web W rises in temperature and then evaporates, and the thickness of the web W becomes thinner and the fiber density is increased. The temperature of the moisture and the binder (starch or dextrin) rises due to heat, and the fiber density increases due to pressure, causing the binder to gelatinize, and then the moisture evaporates, causing a plurality of fibers to bond together via the gelatinized binder. Furthermore, the moisture evaporates due to heat, and the fiber density increases due to pressure, causing a plurality of fibers to bond together through hydrogen bonds. This makes it possible to form a sheet-like fibrous body S with better mechanical strength. In addition, the fibrous body S formed by evaporating the moisture has a weaker adhesive force than the web W before heating, so that the fibrous body S can be prevented from sticking to the heating section 80.

[0052] The heating section 80 of the present embodiment has a pressurizing and heating section 84 that pressurizes and heats the web W. The pressurizing and heating section 84 can be configured using, for example, a heating roller and a heat press molding machine. In the illustrated example, the pressurizing and heating section 84 is a pair of heating rollers 86. The number of heating rollers 86 is not particularly limited. The pressurizing and heating section 84 can simultaneously pressurize and heat the web W. In addition, the configuration of the fibrous body manufacturing apparatus 100 can be simplified.

[0053] 1, the cutting unit 90 cuts the fibrous body S formed by the heating unit 80. In the illustrated example, the cutting unit 90 has a first cutting unit 92 that cuts the fibrous body S in a direction intersecting the conveyance direction of the fibrous body S, and a second cutting unit 94 that cuts the fibrous body S in a direction parallel to the conveyance direction. The second cutting unit 94 cuts the fibrous body S that has passed through the first cutting unit 92, for example. In this manner, a single sheet of fibrous material S having a predetermined size is formed. The cut single sheet of fibrous material S is discharged to a discharge receiving portion 96.

[0054] Next, a method for producing a fibrous body will be described. In this embodiment, a method for producing a fibrous material S in a fibrous material producing apparatus 100 will be described.

[0055] As shown in FIG. 3, in the depositing step (step S11), a material containing fibers and starch or dextrin is dry-deposited on a first mesh belt 72 serving as a first conveyor belt to form a web W. In detail, a mixture containing defibrated fibers and a binder (starch or dextrin) is dry-deposited to form the web W. The fibers are defibrated material defibrated by the defibrator unit 20, the binder is supplied from the binder supply unit 52, and the mixture is formed by the mixing unit 50. Then, the mixture is dry-deposited by the depositing unit 60 and the second web forming unit 70 to form the web W.

[0056] Next, in the conveying process (step S12), the first side Wa of the web W is peeled off from the first mesh belt 72, and the second side Wb of the web W, which is the side opposite to the first side Wa peeled off from the first mesh belt 72, is brought into contact with the second mesh belt 78a serving as a second conveying belt to convey the web W. In detail, an upward airflow is generated on the second mesh belt 78a by the suction mechanism 78c of the conveying section 78, and the web W is sucked in. As a result, the first surface Wa of the web W is peeled off from the first mesh belt 72, and the web W is conveyed with the second surface Wb in contact with the second mesh belt 78a.

[0057] In the moisture imparting step (step S13), moisture is imparted to the web W in contact with the second mesh belt 78a toward the first surface Wa. That is, in this embodiment, moisture is imparted to the web W while the web W is being transported in the transport step. In detail, moisture is supplied from the moisture imparting section 79. In this process, water vapor or mist is imparted to the web W as moisture. In this way, moisture can be imparted more uniformly to the web W, and the fibrous body S can be manufactured with a simpler device configuration. The moisture imparted to the web W does not contain starch or dextrin. The amount of water imparted in the moisture imparting process can be controlled, for example, by the moisture content of the web W. The moisture content of the web W to which moisture has been imparted in the moisture imparting process is preferably 12% by mass or more and 40% by mass or less. When the amount of moisture imparted is about this level, a fibrous body S having superior strength can be manufactured while suppressing the amount of energy, such as electricity, required to heat and dry the web W. In addition, by applying moisture to the first surface Wa of the web W, the second surface Wb side can be transported with weaker adhesive strength than the first surface Wa side, which makes it possible to prevent the moistened web W from sticking to the second mesh belt 78a. Furthermore, by adding moisture to the web W formed by depositing a material containing starch or dextrin, the web W can be transported in a state in which the binding strength of starch or the like is not fully expressed, as compared with the case in which moisture containing starch or dextrin is added to the web, and the web W can be prevented from sticking to members such as the first mesh belt 72 and the second mesh belt 78a. This effect is particularly remarkable when moisture is added so that the moisture content of the web W is 12% by mass or more.

[0058] Furthermore, by applying moisture to the first surface Wa side of the web W in contact with the second mesh belt 78a, the second surface Wb side has weaker adhesive strength than the first surface Wa side, so that the web W to which moisture has been applied can be prevented from sticking to the second mesh belt 78a. In the present embodiment, moisture is applied to the web W in contact with the second mesh belt 78a. On the other hand, for example, if moisture is applied to the web W in a state where it is not in contact with the second mesh belt 78a, etc., there is a risk that the web W will tear as the amount of moisture contained in the web W increases. However, in the present embodiment, moisture is applied to the web W in a state where it is supported by the second mesh belt 78a, so that tearing of the web W due to an increase in the amount of moisture contained in the web W can be suppressed.

[0059] Next, in the heating step (step S14), the web W peeled off from the second mesh belt 78a is brought into contact with the heating unit 80 (heating roller 86) to heat the web W, and the fibers are bonded together by starch or dextrin to form the fibrous body S. In the heating step, the web W is heated and pressurized at the same time. This makes it possible to reduce the number of manufacturing steps. In detail, a pair of heating rollers 86 of the heating section 80 apply pressure to the web W to thin the web and increase the fiber density in the web W. The pressure applied to the web W is preferably 0.1 MPa to 15 MPa, more preferably 0.2 MPa to 10 MPa, and even more preferably 0.4 MPa to 8 MPa. If the pressure applied to the web W in the heating step is within this range, fiber deterioration can be suppressed, and a fibrous body S with good strength can be manufactured again by using the defibrated material obtained by defibrating the manufactured fibrous body S as a raw material.

[0060] In the heating step, heat is applied to the web W to evaporate the moisture contained in the web W. In the heating step, the web W is heated to a temperature of 60°C or higher and 100°C or lower. This allows the binding strength of the starch or dextrin to be fully exerted. Furthermore, the time required for the heating step can be reduced, and the fibrous material S can be produced with less energy.

[0061] Here, in the fibrous body manufacturing method of this embodiment, the web W peeled off from the second mesh belt 78a is directly supplied to the heating section 80 (heating roller 86). "Directly supplied" means that the web W peeled off from the second mesh belt 78a is supplied without contacting other members. That is, in the fibrous body manufacturing method of this embodiment, the web W peeled off from the second mesh belt 78a is not brought into contact with members other than the heating section 80 (heating roller 86) before the heating step. In other words, the web W peeled off from the second mesh belt 78a is fed into the heating roller 86 without contacting members such as a transport roller or a guide. Therefore, the web W becomes more sticky when moisture is added, but by inserting the web W peeled off from the second mesh belt 78a into the heating section 80 (heating roller 86) without touching it, the web W before heating can be prevented from sticking to components such as the conveying member.

[0062] Furthermore, since the web W peeled off from the second mesh belt 78a is heated, the web W can be prevented from sticking to the second mesh belt 78a during heating.

[0063] In addition, since a relatively low pressure is applied to the web W in the heating process, a small manufacturing device can be used, and damage to the fibers is relatively small, so that the fibrous body S can be defibrated again to easily manufacture a new fibrous body S.

[0064] In addition, in the heating step, the web W is heated to a relatively low temperature, which facilitates the formation of hydrogen bonds between the fibers and ensures the strength of the fibrous body S. In addition, the binder can be gelatinized, which allows the fibers to bond with each other via the binder, thereby ensuring the strength of the fibrous body S.

[0065] 2. Second embodiment Next, a second embodiment will be described. The same components as those in the first embodiment are denoted by the same reference numerals, and duplicated explanations will be omitted. In the moisture imparting step in the first embodiment, moisture is imparted to the web W in contact with the second mesh belt 78a, but the present invention is not limited to this. In the moisture imparting step in this embodiment, moisture is imparted to the web W in contact with the first mesh belt 72.

[0066] In this case, for example, a moisture applicator 79 is disposed below the web W supported (piled up) on the first mesh belt 72. Then, moisture is applied from below the web W toward the first surface Wa. This makes it possible to apply moisture to the web W in contact with the first mesh belt 72.

[0067] 4, in this embodiment, after the web W is formed on the first mesh belt 72 in the deposition step (step S21), moisture is imparted to the web W in contact with the first mesh belt 72 in a moisture imparting step (step S22). Thereafter, in a conveying step (step S23), the web W to which moisture has been imparted is peeled off from the first mesh belt 72, and the web W peeled off from the first mesh belt 72 is conveyed. Thereafter, in a heating step (step S24), the web W peeled off from the second mesh belt 78a is brought into contact with a heating unit 80 to heat the web W, thereby forming a fibrous body S. The web W peeled off from the second mesh belt 78a is directly fed into the heating unit 80.

[0068] Even in this manner, the web W can be transported before the binding strength of starch and the like is fully expressed, and by feeding the web W peeled off from the second mesh belt 78a into the heating section 80 (heating roller 86) without touching it, the web W before heating can be prevented from sticking to components such as the transport member.

[0069] 3. Third embodiment Next, a third embodiment will be described. The same components as those in the first embodiment are denoted by the same reference numerals, and duplicated explanations will be omitted. In the first and second embodiments, moisture is applied from below the web W in contact with the first mesh belt 72 or the second mesh belt 78a, but the present invention is not limited to this. For example, moisture may be applied from above the web W in contact with the first mesh belt 72 and the second mesh belt 78a. In this case, for example, the opening of the container 79a of the moisture applicator 79 faces the second surface Wb of the web W. This makes it possible to apply water vapor or mist toward the second surface Wb of the web W. Even in this manner, the web W can be transported before the binding strength of starch and the like is fully expressed, and by feeding the web W peeled off from the second mesh belt 78a into the heating section 80 (heating roller 86) without touching it, the web W before heating can be prevented from sticking to components such as the transport member. [Explanation of symbols]

[0070] Reference Signs List 10...supply section, 12...coarse crushing section, 20...defibration section, 40...sorting section, 50...mixing section, 52...binder supply section, 56...blower, 60...accumulation section, 61...drum section, 62...inlet, 63...housing section, 70...second web forming section, 72...first mesh belt, 74...tension roller, 76...suction mechanism, 78...conveyor section, 78a...second mesh belt, 78b...roller, 78c...suction mechanism, 79...moisture imparting section, 79a...container, 79b...piezoelectric vibrator, 80...heating section, 84...pressurizing and heating section, 86...heating roller, 90...cutting section, 96...discharge receiving section, 100...fibrous body manufacturing apparatus, W...web, Wa...first surface, Wb...second surface.

Claims

1. A fibrous body manufacturing method in a fibrous body manufacturing apparatus including a depositing section that forms a web on a first conveyor belt, a conveying section having a second conveyor belt that conveys the web, a moisture imparting section that imparts moisture to the web, and a heating section that heats the web to which the moisture has been imparted, comprising: a depositing step of dry depositing a material comprising fibers and starch or dextrin onto the first transport belt to form the web; a conveying step of peeling a first surface of the web from the first conveyor belt, and conveying the web by bringing a second surface of the web, which is the surface opposite to the first surface peeled from the first conveyor belt, into contact with the second conveyor belt; a moisture imparting step of imparting moisture to the web in contact with the first conveyor belt or the second conveyor belt; a heating step of bringing the heating section into contact with the web peeled off from the second conveyor belt to heat the web and bond the fibers together with the starch or dextrin to form a fibrous body, The web peeled off from the second conveyor belt is directly supplied to the heating section.

2. The method for producing a fiber body according to claim 1, In the moisture imparting step, The method for producing a fibrous body, wherein the moisture is water vapor or mist applied to the web.

3. The method for producing a fibrous body according to claim 1 or 2, In the moisture imparting step, The moisture is applied to the web in contact with the second transport belt toward the first surface.

4. A method for producing a fibrous body according to any one of claims 1 to 3, The moisture content of the web to which moisture has been added in the moisture adding step is 12% by mass or more and 40% by mass or less.

5. A method for producing a fibrous body according to any one of claims 1 to 4, comprising the steps of: The method for producing a fibrous body, wherein the web is heated to 60° C. or higher in the heating step.

6. A method for producing a fibrous body according to any one of claims 1 to 5, The method for producing a fibrous body, wherein in the heating step, the web is heated and pressurized at the same time.

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