JP2019023318A - Complex - Google Patents

Abstract

To provide a sheet production device using a thermally fusible resin that prevents inter-fiber desorption.SOLUTION: A sheet production device has a mixture part that mixes a fiber and a complex in the air, and a molding part that deposits a mixture mixed by the mixture part and heats it to mold a sheet. The complex comprises resin particles having surfaces at least partially coated with inorganic fine particles, and the complex has an average charge amount of 40 μC/g or more in terms of an absolute value.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sheet manufacturing apparatus and a sheet manufacturing method.

  It has been practiced for a long time to deposit a fibrous substance and obtain a sheet-like or film-like molded body by applying a binding force between the deposited fibers. A typical example is the production of paper by paper making using water (paper making). Even now, the papermaking method is widely used as one of the methods for producing paper. In general, paper produced by a papermaking method is entangled with cellulose fibers derived from, for example, wood, and partially bound to each other by a binder (paper strength enhancer (starch glue, water-soluble resin, etc.)). Many have a structure.

  According to the paper making method, fibers can be deposited with good uniformity, and when a paper strength enhancer is used for bonding between the fibers, the paper strength enhancer is also uniform within the paper surface. It can be dispersed (distributed) in a good state. However, since the paper making method is wet, it is necessary to use a large amount of water, and after the paper is formed, there is a need for dehydration, drying, and the like. Moreover, the used water needs to be appropriately treated as waste water. Therefore, it has become difficult to meet the recent demands for energy saving and environmental protection. In addition, the equipment used for the papermaking method often requires large utilities such as water, electric power, and drainage facilities, and it is difficult to reduce the size. From these viewpoints, as a paper manufacturing method replacing the papermaking method, a method called a dry method that uses no or little water is expected.

  For example, the technique described in Patent Document 1 discloses an attempt to bond fibers with a heat-fusible synthetic resin in an airlaid nonwoven fabric containing a highly water-absorbent resin.

JP 2011-099172 A

  However, in the technique described in Patent Document 1, the heat-fusible resin is in the form of powder, and there is a risk of detachment from the fibers during airlaid. Paragraph 0013 of the same document states that if the heat-fusible powder is too small, it passes through the mesh conveyor (mesh belt) and it is difficult to fix between the fibers. Therefore, this document states that it is preferable to use a heat-fusible resin powder having a relatively large particle size (20 mesh pass, 300 mesh on).

  However, if the particle size of the resin is large, the uniformity of the resin distribution in the product sheet may be impaired. Therefore, in order to uniformly disperse the resin between the fibers, it is desirable that the particle diameter of the resin is smaller.

  Further, when forming a web by air laid, suction is generally performed from below the mesh belt. Then, if the resin particle diameter is made smaller than the size of the opening of the mesh belt, it is considered that the resin is easily detached from the fibers during web formation. For this reason, even if the particle diameter of the resin is reduced, it is necessary to devise a technique that makes it difficult to detach from between the fibers.

  One of the objects according to some embodiments of the present invention is to provide a sheet manufacturing apparatus and a sheet manufacturing method using a heat-fusible resin that is not easily detached from between fibers.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

One aspect of the sheet manufacturing apparatus according to the present invention is:
A mixing section for mixing the fiber and the composite in the atmosphere;
Depositing the mixture mixed in the mixing unit and heating to form a sheet; and
With
The composite is a resin particle in which at least a part of the surface is coated with inorganic fine particles,
The absolute value of the average charge amount of the composite is 40 μC / g or more.

  According to the sheet manufacturing apparatus according to this application example, the composite, which is resin particles in which at least a part of the surface is coated with inorganic fine particles, is mixed with the fiber in the air. When the web is formed, it is difficult for the composite to be detached from the fiber. And since a composite_body | complex and a fiber are bound (heat-fusion) in the state, a sheet | seat with favorable intensity | strength can be manufactured.

In the sheet manufacturing apparatus according to the present invention,
The resin particles may have a volume-based average particle size of 25 μm or less.

  According to the sheet manufacturing apparatus, since the composite is as small as 25 μm or less, it is easy to mix and disperse between fibers. Further, since the composite particles are small and light in weight, they are not easily affected by gravity and are not easily detached from the web or sheet.

In the sheet manufacturing apparatus according to the present invention,
The average particle diameter based on volume of the inorganic fine particles may be 40 nm or less.

  When the inorganic fine particles have an average particle diameter of 40 nm or less, the charge amount of the composite can be further increased.

In the sheet manufacturing apparatus according to the present invention,
The composite may not be separated into the resin and the inorganic fine particles during mixing in the mixing unit.

  According to such a sheet manufacturing apparatus, not only the inorganic fine particles are adhered to the resin in the state of the composite, but the composite is integrated to such an extent that the resin and the inorganic fine particles are not separated during mixing. In addition, the inorganic fine particles are less likely to fall off during mixing.

In the sheet manufacturing apparatus according to the present invention,
The molding unit may include a discharge unit that discharges the mixture, a mesh belt that deposits the mixture, and a suction unit that sucks a gas containing the mixture discharged through the mesh belt.

  By sucking through the mesh belt, there is an increased possibility that the composite will be detached from the fiber. However, according to the sheet manufacturing apparatus of this application example, the composite is detached from the fiber even if there is a suction part. This can be suppressed.

In the sheet manufacturing apparatus according to the present invention,
The content of the inorganic fine particles in the composite may be 0.1% by mass or more and less than 4% by mass.

  According to such a sheet manufacturing apparatus, the charging effect can be sufficiently obtained even when the content of the inorganic fine particles in the composite is as small as 0.1% by mass or more and less than 4% by mass. Therefore, the amount of inorganic fine particles used can be reduced.

In the sheet manufacturing apparatus according to the present invention,
The mixing unit may include a plurality of rotating units having rotating blades, and the fibers and the composite may be mixed by passing through the rotating unit.

  According to such a sheet manufacturing apparatus, the composite is more easily charged by being passed through a rotating unit having blades that rotate the fiber and the composite, and is further less likely to be detached from the fiber.

One aspect of the sheet manufacturing method according to the present invention is:
Mixing a fiber, a composite of resin and inorganic fine particles, and mixing in air;
Depositing a mixture of the fibers and the composite, and heating and molding the mixture;
including.

  According to such a sheet manufacturing method, the composite, which is resin particles coated with inorganic fine particles, is mixed in the air together with the fibers. When formed, the composite is less likely to be detached from the fiber, and a sheet having good uniformity such as strength can be produced.

The figure which shows typically the sheet manufacturing apparatus which concerns on this embodiment. The schematic diagram which shows some examples of the cross section of the composite_body | complex which concerns on embodiment. Schematic which shows an example of the suction device which concerns on an experiment example.

  Several embodiments of the present invention will be described below. The embodiments described below illustrate examples of the present invention. The present invention is not limited to the following embodiments, and includes various modified embodiments that are implemented within a range that does not change the gist of the present invention. Note that not all of the configurations described below are essential configurations of the present invention.

1. Sheet manufacturing apparatus The sheet manufacturing apparatus of the present embodiment includes a mixing unit that mixes fibers and a composite in the atmosphere, a molding unit that deposits the mixture mixed in the mixing unit, and heats to form a sheet. The composite is a resin particle in which at least a part of the surface is coated with inorganic fine particles, and the absolute value of the average charge amount of the composite is 40 μC / g or more.

1.1. Configuration First, an example of a sheet manufacturing apparatus according to the present embodiment will be described with reference to the drawings. FIG. 1 is a diagram schematically illustrating a sheet manufacturing apparatus 100 according to the present embodiment.

As shown in FIG. 1, the sheet manufacturing apparatus 100 includes a supply unit 10, a manufacturing unit 102, and a control unit 140. The manufacturing unit 102 manufactures a sheet. The manufacturing unit 102 includes a crushing unit 12, a defibrating unit 20, a classifying unit 30, a sorting unit 40, a first web forming unit 45, and a mixing unit 50.
And a stacking unit 60, a second web forming unit 70, a sheet forming unit 80, and a cutting unit 90.

  The supply unit 10 supplies raw materials to the crushing unit 12. The supply unit 10 is, for example, an automatic input unit for continuously supplying raw materials to the crushing unit 12. The raw material supplied by the supply part 10 contains fibers, such as a used paper and a pulp sheet, for example.

  The crushing unit 12 cuts the raw material supplied by the supply unit 10 into air into pieces. The shape and size of the strip is, for example, a strip of several cm square. In the illustrated example, the crushing unit 12 has a crushing blade 14, and the charged raw material can be cut by the crushing blade 14. As the crushing part 12, a shredder is used, for example. The raw material cut by the crushing unit 12 is received by the hopper 1 and then transferred (conveyed) to the defibrating unit 20 through the pipe 2.

  The defibrating unit 20 defibrates the raw material cut by the crushing unit 12. Here, “defibration” means unraveling a raw material (a material to be defibrated) formed by binding a plurality of fibers into individual fibers. The defibrating unit 20 also has a function of separating substances such as resin particles, ink, toner, and a bleeding inhibitor adhering to the raw material from the fibers.

  What has passed through the defibrating unit 20 is referred to as “defibrated material”. In addition to the defibrated fibers that have been unraveled, the “defibrated material” includes resin particles (resins that bind multiple fibers together), ink, toner, etc. In some cases, additives such as colorants, anti-bleeding materials, and paper strength enhancing agents are included. The shape of the defibrated material that has been unraveled is a string shape or a ribbon shape. The unraveled defibrated material may exist in an unentangled state (independent state) with other undisentangled fibers, or entangled with other undisentangled defibrated material to form a lump. It may exist in a state (a state forming a so-called “dama”).

  The defibrating unit 20 defibrates in a dry manner in the atmosphere (in the air). Specifically, an impeller mill is used as the defibrating unit 20. The defibrating unit 20 has a function of generating an air flow that sucks the raw material and discharges the defibrated material. Thereby, the defibrating unit 20 can suck the raw material together with the airflow from the introduction port 22 by the airflow generated by itself, defibrate it, and transport it to the discharge port 24. The defibrated material that has passed through the defibrating unit 20 is transferred to the classifying unit 30 via the tube 3.

  The classifying unit 30 classifies the defibrated material that has passed through the defibrating unit 20. Specifically, the classifying unit 30 separates and removes relatively small ones or low density ones (resin particles, colorants, additives, etc.) among the defibrated materials. Thereby, the ratio for which the fiber which is a comparatively large or high density thing among defibrated materials can be raised.

  As the classification unit 30, an airflow classifier is used. The airflow classifier generates a swirling airflow and separates it according to the difference in centrifugal force depending on the size and density of what is classified, and the classification point can be adjusted by adjusting the speed and centrifugal force of the airflow. it can. Specifically, a cyclone, an elbow jet, an eddy classifier, or the like is used as the classification unit 30. In particular, a cyclone as shown in the figure can be suitably used as the classifying unit 30 because of its simple structure.

  The classification unit 30 includes, for example, an inlet 31, a cylindrical part 32 to which the inlet 31 is connected, an inverted conical part 33 that is located below the cylindrical part 32 and continues to the cylindrical part 32, and an inverted conical part 33. The lower discharge port 34 provided in the lower center of the upper portion and the upper discharge port 35 provided in the upper center of the cylindrical portion 32 are provided.

  In the classification unit 30, the airflow on which the defibrated material introduced from the introduction port 31 is changed into a circumferential motion in the cylindrical unit 32. As a result, centrifugal force is applied to the introduced defibrated material, and the classification unit 30 includes fibers (first classified material) larger than the resin particles and ink particles in the defibrated material, and the defibrated material. Among them, it can be separated into resin particles, colorants, additives, etc. (second classified product) that are smaller than the fibers and have a low density. The first classified product is discharged from the lower discharge port 34 and is introduced into the sorting unit 40 through the pipe 4. On the other hand, the second classified product is discharged from the upper discharge port 35 to the receiving portion 36 through the pipe 5.

  The sorting unit 40 introduces the first classified product (defibrated material defibrated by the defibrating unit 20) that has passed through the classifying unit 30 from the introduction port 42, and sorts the first classified product according to the length of the fiber. As the selection unit 40, for example, a sieve is used. The sorting unit 40 has a net (filter, screen), and includes fibers or particles (those that pass through the net, the first sort) that are smaller than the mesh size included in the first classification, Fibers that are larger than the size of the mesh, undefibrated pieces, and lumps (those that do not pass through the net, second selection) can be separated. For example, the first selection is received by the hopper 6 and then transferred to the mixing unit 50 via the pipe 7. The second selected item is returned to the defibrating unit 20 from the discharge port 44 through the pipe 8. Specifically, the sorting unit 40 is a cylindrical sieve that can be rotated by a motor. For the net of the selection unit 40, for example, a metal net, an expanded metal obtained by extending a cut metal plate, or a punching metal in which a hole is formed in the metal plate by a press machine or the like is used.

  The first web forming unit 45 conveys the first sorted product that has passed through the sorting unit 40 to the mixing unit 50. The first web forming unit 45 includes a mesh belt 46, a stretching roller 47, and a suction unit (suction mechanism) 48.

  The suction unit 48 can suck the first sorted matter dispersed in the air through the opening (opening of the mesh) of the sorting unit 40 onto the mesh belt 46. The first selection is deposited on the moving mesh belt 46 to form the web V. The basic configurations of the mesh belt 46, the stretching roller 47, and the suction unit 48 are the same as the mesh belt 72, the stretching roller 74, and the suction mechanism 76 of the second web forming unit 70 described later.

  The web V is formed in a soft and swelled state containing a lot of air by passing through the sorting unit 40 and the first web forming unit 45. The web V deposited on the mesh belt 46 is put into the tube 7 and conveyed to the mixing unit 50.

  The mixing unit 50 mixes the first sorted product that has passed through the sorting unit 40 (the first sorted product conveyed by the first web forming unit 45) and the additive containing resin. The mixing unit 50 includes an additive supply unit 52 that supplies the additive, a pipe 54 that conveys the selected product and the additive, and a blower 56. In the illustrated example, the additive is supplied from the additive supply unit 52 to the pipe 54 via the hopper 9. The tube 54 is continuous with the tube 7.

  In the mixing unit 50, an air flow is generated by the blower 56, and the first selection product and the additive can be mixed and conveyed in the pipe 54. In addition, the mechanism which mixes a 1st selection material and an additive is not specifically limited, It may stir with the blade | wing which rotates at high speed, and uses rotation of a container like a V-type mixer. There may be.

  As the additive supply unit 52, a screw feeder as shown in FIG. 1 or a disk feeder (not shown) is used. The additive supplied from the additive supply unit 52 includes a resin for binding a plurality of fibers. At the time when the resin is supplied, the plurality of fibers are not bound. The resin melts when passing through the sheet forming portion 80 and binds a plurality of fibers.

  The resin supplied from the additive supply unit 52 is a thermoplastic resin or a thermosetting resin. For example, AS resin, ABS resin, polypropylene, polyethylene, polyvinyl chloride, polystyrene, acrylic resin, polyester resin, polyethylene terephthalate, Polyphenylene ether, polybutylene terephthalate, nylon, polyamide, polycarbonate, polyacetal, polyphenylene sulfide, polyether ether ketone, and the like. These resins may be used alone or in combination. The additive supplied from the additive supply unit 52 may be fibrous or powdery.

  In addition to the resin that binds the fibers, the additive supplied from the additive supply unit 52 prevents coloring of the fibers and the aggregation of the fibers depending on the type of sheet to be produced. A coagulation inhibitor, a flame retardant for making fibers difficult to burn, and the like may be included. The mixture (mixture of the first classified product and the additive) that has passed through the mixing unit 50 is transferred to the deposition unit 60 via the pipe 54.

  The depositing unit 60 introduces the mixture that has passed through the mixing unit 50 from the introduction port 62, loosens the entangled defibrated material (fibers), and lowers it while dispersing it in the air. Furthermore, when the additive resin supplied from the additive supply unit 52 is fibrous, the deposition unit 60 loosens the entangled resin. Thereby, the deposition unit 60 can deposit the mixture on the second web forming unit 70 with good uniformity.

  As the deposition unit 60, a rotating cylindrical sieve is used. The deposition unit 60 has a net, and drops fibers or particles (those that pass through the net) included in the mixture that has passed through the mixing unit 50 that are smaller than the mesh opening size. The configuration of the deposition unit 60 is the same as the configuration of the sorting unit 40, for example.

  It should be noted that the “sieving” of the depositing unit 60 may not have a function of selecting a specific object. That is, the “sieving” used as the depositing unit 60 means that the net is provided, and the depositing unit 60 may drop all of the mixture introduced into the depositing unit 60.

  The second web forming unit 70 deposits the passing material that has passed through the deposition unit 60 to form the web W. The second web forming unit 70 includes, for example, a mesh belt 72, a tension roller 74, and a suction mechanism 76.

  While moving, the mesh belt 72 accumulates the passing material that has passed through the opening of the accumulation unit 60 (the opening of the mesh). The mesh belt 72 is stretched by a stretching roller 74, and is configured to allow air to pass therethrough. The mesh belt 72 moves as the stretching roller 74 rotates. While the mesh belt 72 continuously moves, the passing material that has passed through the accumulation portion 60 is continuously piled up, whereby the web W is formed on the mesh belt 72. The mesh belt 72 is made of, for example, metal, resin, cloth, or non-woven fabric.

  The suction mechanism 76 is provided below the mesh belt 72 (on the side opposite to the accumulation unit 60 side). The suction mechanism 76 can generate an air flow directed downward (air flow directed from the accumulation unit 60 toward the mesh belt 72). By the suction mechanism 76, the mixture dispersed in the air by the deposition unit 60 can be sucked onto the mesh belt 72. Thereby, the discharge speed from the deposition part 60 can be increased. Furthermore, the suction mechanism 76 can form a downflow in the dropping path of the mixture, and can prevent the defibrated material and additives from being entangled during the dropping.

  As described above, the web W in a state where it contains a lot of air and is softly swollen is formed by passing through the deposition unit 60 and the second web forming unit 70 (web forming step). The web W deposited on the mesh belt 72 is conveyed to the sheet forming unit 80.

  In the illustrated example, a humidity control unit 78 that adjusts the humidity of the web W is provided. The humidity control unit 78 can adjust the amount ratio of the web W and water by adding water or water vapor to the web W.

  The sheet forming unit 80 forms the sheet S by pressurizing and heating the web W deposited on the mesh belt 72. In the sheet forming unit 80, by heating the mixture of the defibrated material and the additive mixed in the web W, the plurality of fibers in the mixture are bound to each other via the additive (resin). Can do.

  As the sheet forming unit 80, for example, a heating roller (heater roller), a hot press molding machine, a hot plate, a hot air blower, an infrared heater, or a flash fixing device is used. In the illustrated example, the sheet forming unit 80 includes a first binding unit 82 and a second binding unit 84, and the binding units 82 and 84 each include a pair of heating rollers 86. Since the binding portions 82 and 84 are configured as the heating roller 86, the web W is continuously conveyed as compared with the case where the binding portions 82 and 84 are configured as a plate-like press device (flat plate press device). Sheet S can be formed. The number of heating rollers 86 is not particularly limited.

  The cutting unit 90 cuts the sheet S formed by the sheet forming unit 80. In the illustrated example, the cutting unit 90 includes a first cutting unit 92 that cuts the sheet S in a direction that intersects the conveyance direction of the sheet S, and a second cutting unit 94 that cuts the sheet S in a direction parallel to the conveyance direction. ,have. The second cutting unit 94 cuts the sheet S that has passed through the first cutting unit 92, for example.

  Thus, a single-sheet sheet S having a predetermined size is formed. The cut sheet S is discharged to the discharge unit 96.

1.2. Fiber In the sheet manufacturing apparatus 100 of the present embodiment, the raw material is not particularly limited, and a wide range of fiber materials can be used. Examples of fibers include natural fibers (animal fibers, plant fibers), chemical fibers (organic fibers, inorganic fibers, organic-inorganic composite fibers), and more specifically, cellulose, silk, wool, cotton, cannabis, kenaf, flax. , Fiber made of ramie, burlap, manila hemp, sisal hemp, conifer, hardwood, etc., rayon, lyocell, cupra, vinylon, acrylic, nylon, aramid, polyester, polyethylene, polypropylene, polyurethane, polyimide, carbon, glass, metal These fibers may be used, and these may be used singly, mixed as appropriate, or used as regenerated fiber after purification. Examples of the raw material include waste paper and waste cloth, and it is sufficient that at least one of these fibers is included. Moreover, the fiber may be dried, and liquids, such as water and an organic solvent, may be contained or impregnated. Various surface treatments may be performed. The material of the fiber may be a pure substance or a material including a plurality of components such as impurities, additives, and other components.

  Thus, although the sheet manufacturing apparatus 100 of this embodiment can use various kinds of raw materials, among these, waste paper and pulp sheets containing cellulose fibers are relatively hydrophilic and difficult to be charged. The effect of improving the adhesion between the composite and the fiber due to the composite described later is more remarkable than in the case of other fibers.

When the fiber used in this embodiment is an independent single fiber, its average diameter (if the cross section is not a circle, the largest one among the lengths in the direction perpendicular to the longitudinal direction, Alternatively, when a circle having an area equal to the cross-sectional area is assumed, the diameter of the circle (equivalent circle diameter) is 1 μm or more and 1000 μm or less on average, preferably 2 μm or more and 500 μm or less, more preferably 3 μm or more and 200 μm It is as follows.

  The length of the fiber used in the sheet manufacturing apparatus 100 of the present embodiment is not particularly limited, but the length along the longitudinal direction of the single fiber is 1 μm or more and 5 mm or less, preferably They are 2 micrometers or more and 3 mm or less, More preferably, they are 3 micrometers or more and 2 mm or less. When the length of the fiber is short, it is difficult to bind to the composite, and the strength of the sheet may be insufficient. However, a sheet having sufficient strength can be obtained within the above range.

  The average length of the fibers is 20 μm or more and 3600 μm or less, preferably 200 μm or more and 2700 μm or less, more preferably 300 μm or more and 2300 μm or less, as a length-length weighted average fiber length. Further, the fiber length may have a variation (distribution). When a normal distribution is assumed in a distribution obtained by an n number of 100 or more for the length of an independent fiber, σ May be 1 μm or more and 1100 μm or less, preferably 1 μm or more and 900 μm or less, more preferably 1 μm or more and 600 μm or less.

  The thickness and length of the fiber can be measured with various optical microscopes, scanning electron microscopes (SEM), transmission electron microscopes, fiber testers, and the like. In the case of microscopic observation, pretreatment of the observation sample is appropriately performed as necessary, so that cross-sectional observation and observation in a state where both ends of an independent single fiber are pulled so as not to break as necessary. Is possible.

  In the sheet manufacturing apparatus 100 of the present embodiment, the fiber raw material is defibrated by the defibrating unit 20 and conveyed to the mixing unit 50 through the classification unit 30 and the sorting unit 40 as the first selected product. When the mesh belt 46 and the suction unit (suction mechanism) 48 of the sorting unit 40 can perform the function of the classification unit 30 (removal of resin particles and ink particles from the defibrated material) on the web V, the classification is performed. The unit 30 may be omitted. In that case, the defibrated material defibrated by the defibrating unit 20 is introduced into the sorting unit 40.

1.3. The additive supplied from the composite additive supply unit 52 includes a resin for binding a plurality of fibers. At the time when the resin is supplied, the plurality of fibers are not bound. The resin melts when passing through the sheet forming portion 80 and binds a plurality of fibers.

  In the present embodiment, the additive supplied from the additive supply unit 52 is a composite (particle) in which at least a part of the surface of the resin particle is covered with inorganic fine particles. The complex may be used alone or appropriately mixed with other substances.

  The composite of the present embodiment is supplied from the additive supply unit 52 and receives a frictional charging action when passing through the mixing unit 50 and the deposition unit 60. The charged composite adheres to the fibers and is also deposited on the mesh belt 72 together with the fibers and adheres (electrostatically attracts) to the fibers even in the state of the web W.

  The absolute value of the average charge amount of the composite according to this embodiment is 40 μC / g or more. The higher the absolute value of the average charge amount of the composite, the stronger or more the composite can be attached to the fiber. Therefore, it is preferably 60 μC / g or more, more preferably 70 μC / g or more, and even more preferably 80 μC / g. g or more, particularly preferably 85 μC / g or more.

The amount of charge of such a composite can be measured by friction charging the composites. The charge amount can be measured, for example, by stirring (mixing) a powder called a standard carrier and a composite in the air and measuring the charge amount of the powder. As a standard carrier, for example, a spherical carrier with a ferrite core surface-treated, which can be purchased from the Japan Imaging Society (standard carrier for positively charged or negatively charged polarity toner, available as “P-01 or N-01”). Standard carriers for positively charged polarity toners or negatively charged polarity toners, ferrite carriers available from Powdertech Co., Ltd., etc. can be used.

  More specifically, the absolute value of the average charge amount of the composite can be determined as follows, for example. The mixed powder of 80% by mass of the carrier and 20% by mass of the composite is put into an acrylic container, and the container is placed on a ball mill frame at 100 rpm for 60 seconds, and the container is rotated. ). The absolute value [| μC / g |] of the average charge amount is obtained by measuring the mixed composite and carrier mixture with a suction type small charge amount measuring device (for example, Modl210HS-2 manufactured by Trek). be able to.

  When the absolute value of the average charge amount of the composite is 40 μC / g or more, the charged composite adheres to the fiber and is deposited on the mesh belt 72 together with the fiber to form the web W. Can adhere (electrostatically attract). Such a composite according to this embodiment is realized by the structure, material, and the like described in the following section.

  The particle diameter (volume-based average particle diameter) of the composite particles is preferably 50 μm or less, more preferably 30 μm or less, still more preferably 25 μm or less, and particularly preferably 20 μm or less. When the average particle size is small, the gravity acting on the composite becomes small, so that desorption from the fibers due to its own weight can be suppressed, and since the air resistance becomes small, the air flow generated by the suction mechanism 76 or the like (wind ) Can be suppressed from detaching from between the fibers and due to mechanical vibration. In addition, when the composite is in the above particle size range, the average charge amount of 40 μC / g or more can sufficiently prevent the fiber from being detached from the fiber.

  The mesh belt 72 can be set as appropriate. However, since the composite is attached to the fiber, the particle diameter of the composite is larger than the mesh belt 72 (the size of the hole through which the object passes). Even if it is small, passing through the mesh belt 72 is suppressed. That is, the composite of the present embodiment can obtain a more remarkable effect when the particle diameter of the composite is smaller than the mesh belt 72 openings.

  In addition, the minimum of the average particle diameter of the particle | grains of a composite_body | complex is not specifically limited, For example, it is 10 micrometers, and is arbitrary in the range which can be pulverized by methods, such as a grinding | pulverization. In addition, the average particle diameter of the composite particles may have a distribution, and as long as the resin and the inorganic fine particles are integrated, the above-described effect of suppressing detachment from the fibers can be obtained.

  The volume average particle diameter of the composite particles can be measured, for example, by a particle size distribution measuring apparatus using a laser diffraction scattering method as a measurement principle. Examples of the particle size distribution measuring apparatus include a particle size distribution meter (for example, “Microtrack UPA” manufactured by Nikkiso Co., Ltd.) having a dynamic light scattering method as a measurement principle.

  The complex may contain other components. Examples of other components include organic solvents, surfactants, antifungal agents / preservatives, antioxidants / ultraviolet absorbers, oxygen absorbers, and the like.

1.3.1. Structure of Composite The composite is in a state in which at least a part of the surface of the resin particles is covered with inorganic fine particles, and the resin particles or the inorganic fine particles from the composite are contained in the sheet manufacturing apparatus 100 and / or the web W. In the middle or the sheet S, it is difficult to be separated (difficult to separate). That is, the state in which at least a part of the surface of the resin particle is covered with the inorganic fine particles is a state in which the resin and the inorganic fine particle are kneaded, a state in which the inorganic fine particles are adhered or adhered to the surface of the resin particle, and the surface of the resin particle In a state where the inorganic fine particles are structurally (mechanically) fixed, and a state where the resin particles and the inorganic fine particles are aggregated by electrostatic force, van der Waals force, or the like. . The state in which the inorganic fine particles cover at least a part of the surface of the resin particles may be a state where the inorganic fine particles are encapsulated in the resin particles or a state where the inorganic fine particles are attached to the resin. Furthermore, the state in which those states exist simultaneously may be sufficient. In the present specification, the state in which the inorganic fine particles cover at least a part of the surface of the resin particles is sometimes referred to as a state in which the resin and the inorganic fine particles are integrally provided.

  FIG. 2 schematically shows several aspects of the cross section of the composite integrally including the resin and the inorganic fine particles. As an example of a specific aspect of the composite body integrally including the resin and the wax, for example, as illustrated in FIG. 2A, the resin re is in a state where the inorganic fine particles in are kneaded and dispersed, and at least Examples include a composite co in which some inorganic fine particles in are exposed on the surface of the composite co.

  Further, as shown in FIG. 2B, the inorganic fine particles in may be arranged so as to cover the surface of the resin re. That is, as an example of a specific aspect of the composite body integrally including the resin and the wax, as shown in FIG. 2B, the inorganic fine particles in are embedded in the surface of the resin re, adhered, and / or adhered. A complex co. The adhesion and / or adhesion of both components in this example may be based on electrostatic force, van der Waals force, or the like.

  In the structure of the composite co shown in FIG. 2, the inorganic fine particles in cover a part of the surface of the resin re particles, but may cover the entire surface of the resin re particles or the resin re particles. Multiple surfaces may be covered. Further, a structure in which the structure shown in FIG. 2A and the structure shown in FIG. 2B are combined may be used.

  In the example of FIG. 2, the outer shape of the composite and the outer shape of the inorganic fine particles are both substantially spherical, but the outer shape of the composite and the inorganic fine particles is not particularly limited. The shape may be a shape such as a shape, needle shape, or irregular shape. However, the shape of the composite is more preferably as close to a sphere as possible because it is easily arranged between the fibers in the mixing unit 50.

  In addition, the composite of any structure shown in FIG. 2 is difficult to separate into resin and inorganic fine particles during mixing in the mixing unit 50. In the present application, when the composite is not divided into resin and inorganic fine particles, it is desirable not to separate all of the composite particles with respect to the number of composite particles in the entire powder, but in fact, not all are separated. It is difficult to put it in a state. Therefore, the state where it is not separated means that the average number of composite particles of 70% or more with respect to the number of composite particles in the entire powder is not divided into resin and inorganic fine particles.

The structure of the complex co as shown in FIGS. 2A and 2B can be confirmed by various analysis means such as a structure analysis method such as an electron microscope. Further, whether or not the resin particles are coated with inorganic fine particles can be evaluated, for example, by measuring the angle of repose. The angle of repose can be measured, for example, according to the method of “Alumina powder? Part 2: Physical property measurement method-2: angle of repose” of JIS R 9301-2-2: 1999. This can be confirmed from the fact that the angle of repose is small in the composite coated with inorganic fine particles compared to the resin particles not coated with inorganic fine particles.

1.3.2. The function of the composite has exemplified several aspects of the composite integrally including the resin and the inorganic fine particles. However, in any aspect, when receiving various treatments in the sheet manufacturing apparatus 100, the web W, When formed into the sheet S, the resin and the inorganic fine particles are difficult to separate, and the composite adsorbed on the fiber is not easily detached from the fiber.

  When the inorganic fine particles are arranged on the surface of the resin particles, the inorganic fine particles have a function of improving the charge amount of the resin particles (composite) compared to the case where there are no inorganic fine particles. Various kinds of inorganic fine particles can be used, but in the sheet manufacturing apparatus 100 of the present embodiment, water is not used or hardly used, so that it is disposed on the surface of the composite (may be a coating (coating) or the like). Are preferably used.

  The inorganic fine particles generate an adsorbing force (adhesive force) between the composite and the fiber by increasing the chargeability of the composite. Therefore, when the web W is deposited on the mesh belt 72 of the second web forming unit 70 of the sheet manufacturing apparatus 100, it is possible to make it difficult for the composite to be detached from the fibers. Thereby, the mechanical strength of the sheet S manufactured by the sheet manufacturing apparatus 100 can be easily made predetermined. That is, when the composite of this embodiment is disposed between fibers, it has a sufficient adhesive force (electrostatic bonding force) to the fibers, and thus is not easily detached from the fibers. The reason why such an effect is obtained is that the inorganic fine particles are arranged on the surface of the resin particles, so that it is easier to be frictionally charged, and in the mixing unit 50, the composite is mixed with the fibers in the atmosphere. This is presumably because static electricity is generated by friction, and the composite (resin) adheres to the fibers.

1.3.3. The material of the composite The type of resin (component of resin particles) that is a component of the composite has already been described, and is a thermoplastic resin or a thermosetting resin, for example, AS resin, ABS resin, polypropylene, polyethylene, Polyvinyl chloride, polystyrene, acrylic resin, polyester resin, polyethylene terephthalate, polyphenylene ether, polybutylene terephthalate, nylon, polyamide, polycarbonate, polyacetal, polyphenylene sulfide, polyether ether ketone, and the like. These resins may be used alone or in combination.

  More specifically, the type of resin (component of resin particles) that is a component of the composite may be either a natural resin or a synthetic resin, and may be either a thermoplastic resin or a thermosetting resin. In the sheet manufacturing apparatus 100 of the present embodiment, the resin constituting the composite is preferably solid at room temperature, and a thermoplastic resin is more preferable in view of binding fibers by heat in the sheet forming unit 80. .

  Examples of natural resins include rosin, dammar, mastic, copal, phlegm, shellac, phlebotomy, sandalac, colophonium, etc., and those that are used alone or as appropriate mixed, and these are appropriately modified. Also good.

  Among the synthetic resins, examples of the thermosetting resin include thermosetting resins such as phenol resin, epoxy resin, melamine resin, urea resin, unsaturated polyester resin, alkyd resin, polyurethane, and thermosetting polyimide resin.

  Among the synthetic resins, thermoplastic resins include AS resin, ABS resin, polypropylene, polyethylene, polyvinyl chloride, polystyrene, acrylic resin, polyester resin, polyethylene terephthalate, polyphenylene ether, polybutylene terephthalate, nylon, polyamide, polycarbonate, Examples include polyacetal, polyphenylene sulfide, polyether ether ketone, and the like.

  In addition, copolymerization and modification may be performed, and such resin systems include styrene resins, acrylic resins, styrene-acrylic copolymer resins, olefin resins, vinyl chloride resins, and polyester resins. Examples thereof include resins, polyamide resins, polyurethane resins, polyvinyl alcohol resins, vinyl ether resins, N-vinyl resins, styrene-butadiene resins, and the like.

  On the other hand, examples of the inorganic fine particles include fine particles made of an inorganic substance. By disposing the fine particles on the surface of the resin particles (composite), a very excellent charging effect can be obtained.

  Specific examples of the material of the inorganic fine particles include silica (silicon oxide), titanium oxide, aluminum oxide, zinc oxide, cerium oxide, magnesium oxide, zirconium oxide, strontium titanate, barium titanate, and calcium carbonate. Further, the inorganic fine particles arranged on the surface of the resin particles may be one kind or plural kinds.

  The volume-based average (primary) particle diameter (volume average particle diameter) of the inorganic fine particles is not particularly limited, but is 1 nm to 100 nm, preferably 2 nm to 80 nm, more preferably 5 nm to 50 nm, and still more preferably 10 nm or more. 40 nm or less. Inorganic fine particles are close to the category of so-called nanoparticles and have a small particle diameter, so they are generally primary particles. However, even if a plurality of primary particles are combined to form higher-order particles. Good. The inorganic fine particles of the present embodiment have a small particle size, a large surface area ratio per weight, and a large surface when frictionally charged. Therefore, if the particle diameter of the inorganic fine particles is within the above range, a good charging effect can be obtained. In addition, when the particle diameter of the inorganic fine particles is within the above range, the surface of the composite can be satisfactorily coated, and also in this respect, a sufficient charging effect can be stably provided.

  The average (primary) particle diameter of the inorganic fine particles can be measured according to a conventional method from the relationship between the specific surface area and the density determined by, for example, the BET method.

  If the content of the inorganic fine particles in the composite is 0.01% by mass or more and 10% by mass or less with respect to 100% by mass of the composite, the above effect can be obtained, and the effect is further enhanced, and / or From the viewpoint of effectively using inorganic fine particles (when the amount of inorganic fine particles is too large, the amount of charge is difficult to increase even if the amount added is increased), preferably 0.05 mass relative to 100 mass% of the composite. % To 5% by mass, more preferably 0.1% to 4% by mass, and still more preferably 0.1% to 3% by mass.

  The method for arranging (coating) the inorganic fine particles on the surface of the composite is not particularly limited, and the inorganic fine particles may be blended together with the resin when forming the composite by the above-described melt-kneading. However, in this case, since most of the inorganic fine particles are arranged inside the composite, the charging effect with respect to the added amount of the inorganic fine particles is reduced. It is more preferable that the inorganic fine particles are disposed on the surface of the composite as much as possible in view of the charging generation mechanism. Examples of the arrangement of the inorganic fine particles on the surface of the composite include coating and covering, but it is not always necessary to cover the entire surface of the composite. In addition, the coverage may exceed 100%, but if it is approximately 300% or more, the action of binding the composite and the fiber may be impaired, so an appropriate coverage is selected according to the situation. To do.

Various methods can be considered as a method for disposing the inorganic fine particles on the surface of the composite, but it is possible to achieve the effect by simply mixing the two and adhering them to the surface by electrostatic force or van der Waals force. Concerns remain. Therefore, a method in which the composite and inorganic fine particles are put into a mixer that rotates at high speed and uniformly mixed is preferable. As such an apparatus, a known apparatus can be used, and an FM mixer, a Henschel mixer, a super mixer, or the like can be used. By such a method, inorganic fine particles can be arranged on the surface of the composite. The inorganic fine particles arranged by such a method may be arranged in a state where at least a part of the fine particles bites into the surface of the composite or is indented, and the inorganic fine particles can be more difficult to drop off from the composite, A charging effect can be achieved stably. Further, when such a method is used, the above arrangement can be easily realized in a system containing little or no moisture. Moreover, even if there are inorganic fine particles that do not penetrate into the composite, such an effect can be sufficiently obtained. It should be noted that the state in which the inorganic fine particles dig into the surface of the composite or the state in which it is sunk can be confirmed by various electron microscopes.

  A sufficient charging effect can be obtained if the ratio of the inorganic fine particles to be coated on the surface of the composite (area ratio: this may be referred to as a coverage in this specification) is 20% or more and 100% or less. . The coverage can be adjusted by charging into an apparatus such as an FM mixer. Further, if the specific surface area of the inorganic fine particles and the composite is known, it can be adjusted by the mass (weight) of each component at the time of preparation. Moreover, a coverage can also be measured with various electron microscopes. In addition, when the inorganic fine particles are arranged in such a manner that the inorganic fine particles are not easily detached from the composite, it can be said that the inorganic fine particles are integrally provided in the composite.

  The inorganic fine particles may be surface-modified. Specifically, the surface of inorganic fine particles may be chemically treated with a silane compound to modify the surface and used. Examples of such silane compounds include alkylsilanes such as trimethylsilane, dimethylsilane, triethylsilane, triisopropylsilane, and triisobutylsilane, and silane coupling agents such as vinyltrimethoxysilane and vinyltriethoxysilane. it can.

  Since the composite has inorganic fine particles, the composite easily adheres to the fibers electrostatically, and can be prevented from falling off the fibers and from the web and the sheet. Further, the composite and the fiber can be mixed very well by air flow or stirring by a mixer. The reason is that when the inorganic fine particles are arranged on the surface of the composite, the composite tends to be easily charged with static electricity, and the composite easily adheres to the fiber due to the static electricity. In addition, the composite adhered to the fiber due to the static electricity is not easily detached from the fiber even when a mechanical impact or the like occurs. Therefore, even if it does not use special means other than mixing of a fiber and a composite, it mixes rapidly and drop-off is fully suppressed. Moreover, after the mixture is formed, the adhesion of the composite to the fiber is stable, and the phenomenon of detachment of the composite is not observed.

  It is considered that the composite particles are more strongly attached to the fibers by electrostatic force than when the particles are resin alone. Further, it has been found that the effect of the inorganic fine particles is not impaired even when the resin particles contain a pigment. Furthermore, in general, static electricity is difficult to accumulate when the humidity is high. For example, when the fiber is cellulose, even if some moisture is contained, the adhesion of the composite to the fiber is improved by the presence of inorganic fine particles.

1.3.5. Other components Although it has been stated that the composite may contain a colorant for coloring the fiber and a flame retardant for making the fiber difficult to burn, when it contains at least one of these Can be obtained more easily by blending these into a resin by melt kneading. The inorganic fine particles can be blended by forming such a resin powder and then mixing the resin powder and the inorganic fine particle powder with a high-speed mixer or the like.

In the mixing unit 50, the above-described fibers and the composite are mixed, and the mixing ratio thereof can be appropriately adjusted depending on the strength, use, and the like of the sheet S to be manufactured. If the manufactured sheet S is for office use such as copy paper, the ratio of the composite to the fiber is 5% by mass or more and 70% by mass or less. From the viewpoint of making the composite more difficult to desorb due to gravity when molded into a shape, it is preferably 5% by mass or more and 50% by mass or less.

1.4. Mixing unit The mixing unit 50 provided in the sheet manufacturing apparatus 100 of the present embodiment has a function of mixing fibers and composites. In the mixing unit 50, at least the fibers and the composite are mixed. In the mixing part 50, components other than a fiber and a composite_body | complex may be mixed. In this specification, “mixing a fiber and a composite” is defined as positioning the composite between fibers in a space (system) having a constant volume.

  The mixing process in the mixing unit 50 according to the present embodiment is a method (dry method) in which fibers and composites are introduced into an air stream and diffused in the air stream, and is a hydrodynamic mixing process. “Dry” in mixing refers to a state of mixing in air rather than in water. That is, the mixing unit 50 may function in a dry state, or may function in a state where a liquid that exists as an impurity or a liquid that is intentionally added exists. In the case where the liquid is intentionally added, it is preferable to add the liquid in an amount that does not increase the energy and time for removing the liquid by heating or the like in the subsequent step. In the case of such a method, the air flow in the pipe 54 or the like is more preferably turbulent because the mixing efficiency may be improved.

  The processing capacity of the mixing unit 50 is not particularly limited as long as the fiber (fiber material) and the composite can be mixed, and can be appropriately designed and adjusted according to the manufacturing capacity (throughput) of the sheet manufacturing apparatus 100. . The processing capacity of the mixing unit 50 can be adjusted by changing the flow rate of gas for transferring the fibers and composites in the tube 54, the amount of material introduced, the amount of transfer, and the like.

  The mixture mixed by the mixing unit 50 may be further mixed by another configuration such as a sheet forming unit. In the example of FIG. 1, the mixing unit 50 includes the blower 56 provided in the pipe 54, but may further include a blower (not shown).

  The blower is a mechanism for mixing the fiber and the composite, and has a rotating portion having rotating blades. As the blades rotate, the fibers and / or the composite are rubbed by the blades or collide with the blades. Further, when the blades rotate, the airflow formed by the blades causes the fibers and the fibers, the fibers and the composite, and / or the composite and the composite to collide with each other or be rubbed against each other.

  It is considered that such a collision or friction causes at least the composite to be charged (charged with static electricity) and generate an adhesive force (electrostatic force) for the composite to adhere to the fiber. The strength of such adhesive force also depends on the properties of the fibers and the composite and the blower structure (the shape of the rotating blades, etc.). As shown in FIG. 1, even when one blower 56 is provided, sufficient adhesion can be obtained. However, by providing another blower on the downstream side of the additive supply unit 52, stronger adhesion can be obtained. You may be able to get The number of blowers to be added is not particularly limited. Moreover, when providing a some blower, you may make it share the main functions for every blower, such as providing a blower with big good ventilation power and a blower with larger stirring power (capability to charge). If it does in this way, the adhesive force of the composite_body | complex to a fiber may be able to be heightened more, and when the web W is shape | molded, detachment | desorption of the composite_body | complex from between fibers can be further suppressed.

1.5. Operational Effect In the sheet manufacturing apparatus 100 of the present embodiment, the composite mixed with the fibers in the mixing unit 50 is such that at least a part of the surface of the resin particles is covered with inorganic fine particles. The composite is not easily detached from between the fibers. And since a composite and a fiber are bound in the sheet | seat formation part 80, the dispersibility of resin is favorable and a sheet | seat with favorable uniformity, such as an intensity | strength, can be manufactured.

  The composite used in the sheet manufacturing apparatus 100 of the present embodiment has very good adhesion to fibers. Addition of inorganic fine particles to the resin makes the composite particles easy to be charged due to the property of the inorganic fine particles that are easily charged with static electricity. As a result, the amount of charge of the composite increases and the adhesion to the fibers Will improve.

  Further, the sheet manufacturing apparatus of the present embodiment includes a mesh belt 72 and a suction mechanism 76 that form the web W in the second web forming unit 70, and the suction mechanism 76 is interposed via the mesh belt 72. It can be referred to as a suction unit that sucks the mixture discharged by the deposition unit 60. Such a suction part sucks the deposit through the mesh belt, so that the possibility that the composite is detached from the fiber is increased. However, according to the sheet manufacturing apparatus of the present embodiment, the suction part is provided. Despite being present, it is possible to sufficiently prevent the composite from being detached from the fiber.

2. Sheet manufacturing method The sheet manufacturing method of the present embodiment is a mixture of a fiber, a composite in which a resin and inorganic fine particles are integrated, and a mixture of the fiber and the composite. Depositing and heating to form. Since the fiber, the resin, the inorganic fine particles, and the composite are the same as those described in the above section of the sheet manufacturing apparatus, detailed description thereof is omitted.

  The sheet manufacturing method of the present embodiment includes a step of cutting a pulp sheet or waste paper as a raw material in the air, a defibrating step of unraveling the raw material into a fiber form in the air, and impurities (toner and toner) from the defibrated defibrated material. Paper strength enhancer) and classification process in which fibers shortened by defibration (short fibers) are classified in the air, long fibers (long fibers) from defibrated material and undefibrated pieces that have not been sufficiently defibrated Sorting process for sorting in, dispersion process for dispersing the mixture while dispersing in the air, molding process for depositing the falling mixture in the air and forming it into a web shape, etc., drying process for drying the sheet if necessary And a winding step for winding the formed sheet into a roll, a cutting step for cutting the formed sheet, and at least one step selected from the group consisting of a packaging step for packaging the manufactured sheet. . Since the details of these steps are the same as those described in the section of the sheet manufacturing apparatus, detailed description thereof is omitted.

3. Sheet The sheet S manufactured by the sheet manufacturing apparatus 100 or the sheet manufacturing method of the present embodiment mainly refers to a sheet that is made from at least the above-described fibers. However, it is not limited to a sheet shape, and may be a board shape, a web shape, or a shape having irregularities. The sheet in this specification can be classified into paper and non-woven fabric. The paper includes, for example, a mode in which pulp or waste paper is used as a raw material and is formed into a sheet shape, and includes recording paper for writing and printing, wallpaper, wrapping paper, colored paper, drawing paper, Kent paper, and the like. The non-woven fabric is thicker than paper or has a low strength, and includes general non-woven fabric, fiber board, tissue paper, kitchen paper, cleaner, filter, liquid absorbent material, sound absorber, cushioning material, mat, and the like.

  In addition, in the case of a nonwoven fabric, the space | interval between a fiber is wide (the density of a sheet | seat is small). In contrast, paper has a narrow spacing between fibers (the sheet density is high). Therefore, when the sheet S manufactured by the sheet manufacturing apparatus 100 or the sheet manufacturing method of the present embodiment is paper, the effect of suppressing the detachment of the composite from the fiber and the uniformity of the strength when the sheet is used. The function can be expressed more remarkably.

4). Storage Container The storage container of the present embodiment is used by mixing with fibers, and stores the above-described composite body in which a resin and inorganic fine particles are integrated.

  The composite of this embodiment is supplied to the mixing unit 50 by opening and closing a feeder or a valve. The composite of the present embodiment is supplied in a powder state as an appearance. Therefore, for example, after the composite is manufactured, the apparatus can be configured to be directly supplied to the mixing unit 50 through a pipe or the like. However, depending on the installation location of the apparatus, it is conceivable that the composite is put on a distribution channel as a product, and may be transferred or stored after the composite is manufactured.

  The storage container of the present embodiment has a storage chamber that stores the composite, and the composite can be stored in the storage chamber. That is, the storage container of this embodiment can be referred to as a composite cartridge, and the composite can be easily transported and stored.

  The shape of the container is not particularly limited, and can be a cartridge shape that is compatible with the sheet manufacturing apparatus 100. The container can be formed of, for example, a general polymer material. Further, the storage container may be a box-like robust form or a film (bag) -like flexible form. The material constituting the container is preferably composed of a material having a higher glass transition temperature and melting point than the material of the composite to be accommodated.

  The accommodation chamber for accommodating the complex is not particularly limited as long as the complex can be accommodated and held. The storage chamber can be formed of a film, a molded body, or the like. When the storage chamber is formed of a film, the storage container may be formed including a molded body (housing) that stores the film forming the storage chamber. Further, the storage chamber may be formed of a relatively robust molded body.

  The film or molded body forming the storage chamber is made of a polymer, a metal deposition film, or the like, and may have a multilayer structure. When the storage container is formed of a plurality of members such as a film or a molded body, a welded part or an adhesive part may be formed. Further, when the composite (powder) to be accommodated is affected by alteration or the like due to contact with the atmosphere, the film or the molded body is preferably formed of a material having a low gas permeability. Of the materials of the film and molded body forming the storage chamber, the material of the portion in contact with the composite to be stored is preferably stable with respect to the composite.

  The shape and volume of the storage chamber are not particularly limited. Although the composite is stored in the storage chamber, a solid or gas inert to the composite may be stored together with the composite. The volume of the composite housed in the housing chamber is not particularly limited.

  The storage chamber may have a distribution port through which the inside of the storage chamber communicates with the outside of the storage container and the composite can be taken out of the storage container. The accommodation chamber may be formed with a flow passage other than the circulation port. Such another flow passage may be constituted by, for example, an open valve. In the case where an opening valve is provided in the storage chamber, the position of the opening valve is not particularly limited, but it is disposed on the opposite side to the direction in which gravity acts in a normal posture during transfer, transportation, and use. In some cases, when pressure or the like is generated in the storage chamber, it is difficult to discharge the complex when the pressure is released to the atmosphere.

5. Other Matters The sheet manufacturing apparatus and sheet manufacturing method of the present embodiment, as described above, use water at all or only slightly. It is also possible to produce sheets by adding water.

  As water in such a case, it is preferable to use pure water or ultrapure water such as ion exchange water, ultrafiltration water, reverse osmosis water, and distilled water. In particular, water obtained by sterilizing these waters by ultraviolet irradiation or addition of hydrogen peroxide is preferable because generation of mold and bacteria can be suppressed over a long period of time.

  In this specification, the term “homogeneous” means, in the case of uniform dispersion or mixing, in an object that can define two or more components or two or more components, the presence of one component relative to other components The positions refer to being uniform throughout the system or identical or substantially equal to each other in each part of the system. Further, the uniformity of coloration and the uniformity of color tone indicate that there is no color shading when the sheet is viewed in plan, and the density is uniform.

  In the present specification, terms such as “uniform”, “same”, “equally spaced”, etc. mean that the density, distance, dimensions, etc. are equal. Although it is desirable that these are equal, it is difficult to make them completely equal. Therefore, it is assumed that the values do not become equal due to accumulation of errors and variations.

6). Experimental Examples The experimental examples are shown below to further explain the present invention, but the present invention is not limited to the following examples.

6.1. Preparation of composite (1) Styrene maleic acid resin (Tg: 74 ° C., molecular weight 6600): 1.5 kg
(2) Polyester resin (Tg: 56 ° C., molecular weight 10,000): 8.0 kg
(3) Copper phthalocyanine pigment (Pigment Green 36): 0.5 kg
The above materials were mixed in a hopper, then charged into a twin-screw kneading extruder and melt kneaded at 90 ° C to 135 ° C. Extruded with a die to form a strand and cut into a length of about 5 mm to obtain a pellet.

  The pellets obtained above were treated in a high speed mill for 30 seconds to roughly pulverize the pellets into granules, and then charged into a jet mill to obtain a powder having a particle size range of 1 μm to 40 μm.

  The powder obtained by the jet mill was obtained by a classifier to obtain powdered resin particles (A1) composed of particles having a volume standard average particle size of 12 μm and a particle size range of 5 μm to 23 μm.

6.2. Experimental example 1
(1) Resin particles (A1): 100 g
(2) Inorganic fine particles (M1): 1.5 g
The above material was put into a table-top blender and stirred for 80 seconds at a blade tip speed of 30 m / s to coat the surface of the resin particles (A1) with inorganic fine particles (M1). The presence or absence of coating was confirmed by observing the particle surface with SEM. Furthermore, the confirmation was also made by changing the angle of repose. This was judged from the decrease in the angle of repose when a coating (coating with inorganic fine particles) was formed. As the inorganic fine particles (M1), titanium dioxide having a volume primary particle size of 14 nm whose surface was hydrophobized with alkylsilane was used.

6.3. Experimental example 2
Fine particles of silicon dioxide having a volume-based primary particle size of 12 nm whose surface is modified with trimethylsilane are referred to as inorganic fine particles (M2). The same procedure as in Experimental Example 1 was performed except that the inorganic fine particles (M2) were used instead of the inorganic fine particles (M1) used in Experimental Example 1.

6.4. Experimental example 3
The fine particles of silicon dioxide having a volume-based primary particle size of 20 nm whose surface is modified with trimethylsilane are referred to as inorganic fine particles (M3). It was the same as Experimental Example 1 except that the inorganic fine particles (M3) were used instead of the inorganic fine particles (M1) used in Experimental Example 1.

6.5. Experimental Example 4
The fine particles of silicon dioxide having a volume-based primary particle size of 20 nm whose surface is modified with trimethylsilane are referred to as inorganic fine particles (M4). It was the same as Experimental Example 1 except that the inorganic fine particles (M4) were used instead of the inorganic fine particles (M1) used in Experimental Example 1.

6.6. Experimental Example 5
Resin particles (A1) having nothing coated on the surface were used.

6.7. Measurement of charge amount (1) Standard carrier N-01 (obtained from the Imaging Society of Japan): 4.85 g
(2) Powder of each experimental example (composite or resin particle): 0.15 g
The above was weighed and placed in an acrylic container, and the container was placed on a ball mill mount at 100 rpm for 180 seconds to rotate the container, and the carrier and particles (powder) were mixed. The absolute value [| μC / g |] of the average charge amount was determined for the mixture of the powder and the carrier after mixing with a suction type small charge amount measuring device (Model 210HS-2, manufactured by Trek) and listed in Table 1.

6.8. Evaluation of retention rate of particles to fiber (1) Conifer bleached kraft pulp (NBKP): 16 g
(2) Composite particles (Experimental Examples 1 to 4) or resin particles (Experimental Example 5): 4 g
(3) Particle content: 4 g / (16 g + 4 g) = 20 mass%
The above-mentioned mass is weighed and placed in a transparent polyethylene bag of 520 mm × 600 mm × 0.030 mm, air is blown with an air gun, and the pulp and composite or resin particles are stirred with an air flow to obtain pulp and composite or pulp and resin. A mixture of particles (powder of each experimental example) was mixed.

  5.0 g of each experimental example mixture was taken out and spread evenly with tweezers gently onto a 140 mesh standard sieve. Then, the same sieve was put on the upper side of the sieve and set in the suction device. FIG. 3 shows a schematic diagram of the suction device 200. The suction device 200 used is self-made, and has a configuration as shown in FIG. 3 and includes a funnel-type funnel portion 220 on which a sieve 210 is set, an exhaust device 230, and an exhaust filter 240. In this apparatus, when the sieve 210 on which nothing is placed is installed, the exhaust speed of the exhaust apparatus 230 is adjusted so that the wind speed of the mesh surface of the sieve 210 is 25 ± 1 m / s. As long as this wind speed condition is satisfied, the configuration of the apparatus is not necessarily as shown in FIG. After the sieve 210 is set in the suction device 200 in a state where each mixture is sandwiched by the sieve 210 and suction is performed for 30 seconds, the value when the mass of each remaining mixture is measured is defined as X (g). .

Here, the particle retention rate RV (%) is
RV = (5 × 0.2− (5-X)) / (5 × 0.2) × 100 = (X−4) × 100
It is calculated according to the following formula. The higher the particle retention, the more the mixture is retained between the fibers of the pulp. If RV = 100%, the particles of the mixture do not pass through the sieve 210 by suction. I can say that. The particle retention of each experimental example is shown in Table 1.

  In each experimental example, the weight of the mixture sandwiched between the sieves 210 is 5.0 g, but this mass may be adjusted as appropriate from the test efficiency. However, in each sieve 210 used in the measurement, a volume mixture capable of covering the entire sieve surface is sandwiched. When the mass of the mixture that satisfies this condition is selected, the value of RV obtained tends to be independent of the mass of the mixture.

6.9. Evaluation Results Table 1 summarizes sample properties and particle retention rates for each experimental example.

  As shown in Table 1, it has been found that the charge amount of the obtained powder can be controlled by changing the coating state of the resin particles with the inorganic fine particles. It was also found that the particle retention rate for pulp fibers can be controlled by controlling the charge amount. The larger the charge amount of the particles (composite), the higher the particle retention rate. The higher the particle retention rate, the more easily the resin particles of the complex adhere to the pulp fibers (cellulose) easily. It is thought that it is in a state where it is not detached.

  Further, from Table 1, it was found that when the absolute value of the average charge amount is 40 μC / g or more, the particle retention rate is about 80% or more, so that there is no problem in actual sheet production. . Further, it was found that when the absolute value of the average charge amount was 80 μC / g or more, the particle retention was 95% or more, and the resin particles (composite) were released from the fibers very much, which was further improved. .

  When the sheet has a charge amount in a range as in Experimental Examples 1 to 4, when the sheet is produced in a dry process, the resin component is less likely to be detached from the fiber, and as a result, a tough sheet as designed is produced. It turns out that it is possible.

The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the present invention includes configurations that are substantially the same as the configurations described in the embodiments (configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that exhibits the same operational effects as the configuration described in the embodiment or a configuration that can achieve the same object. In addition, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

DESCRIPTION OF SYMBOLS 1 ... Hopper, 2, 3, 4, 5 ... Pipe, 6 ... Hopper, 7, 8 ... Pipe, 9 ... Hopper, 10 ... Supply part, 12 ... Crushing part, 14 ... Crushing blade, 20 ... Defibration part , 22 ... introduction port, 24 ... discharge port, 30 ... classification part, 31 ... introduction port, 32 ... cylindrical part, 33 ... inverted conical part, 34 ... lower discharge port, 35 ... upper discharge port, 36 ... receiving part, 40 DESCRIPTION OF SYMBOLS ... Sorting part, 42 ... Introduction port, 44 ... Discharge port, 45 ... 1st web formation part, 46 ... Mesh belt, 47 ... Stretching roller, 48 ... Suction part, 50 ... Mixing part, 52 ... Additive supply part, 54 ... Pipe, 56 ... Blower, 60 ... Deposition unit, 62 ... Inlet, 70 ... Second web forming unit, 72 ... Mesh belt, 74 ... Stretching roller, 76 ... Suction mechanism, 78 ... Humidity control unit, 80 ... Sheet forming part, 82 ... first binding part, 84 ... second binding part, 86 ... heating roller, 87a, 87 DESCRIPTION OF SYMBOLS ... Cooling roller, 90 ... Cutting part, 92 ... 1st cutting part, 94 ... 2nd cutting part, 96 ... Discharge part, 100 ... Sheet manufacturing apparatus, 102 ... Manufacturing part, 140 ... Control part, S ... Sheet, V ... Web, W ... web, re ... resin, in ... inorganic fine particles, co ... composite, 200 ... suction device, 210 ... sieve, 220 ... funnel, 230 ... exhaust device, 240 ... exhaust filter

Claims (8)

A mixing section for mixing the fiber and the composite in the atmosphere;
Depositing the mixture mixed in the mixing unit and heating to form a sheet; and
With
The composite is a resin particle in which at least a part of the surface is coated with inorganic fine particles,
The sheet manufacturing apparatus according to claim 1, wherein an absolute value of an average charge amount of the composite is 40 μC / g or more.   The sheet manufacturing apparatus according to claim 1, wherein an average particle diameter of the resin particles based on volume is 25 μm or less.   The sheet manufacturing apparatus according to claim 1 or 2, wherein an average particle diameter of the inorganic fine particles based on a volume is 40 nm or less.   4. The sheet manufacturing apparatus according to claim 1, wherein the composite is not divided into the resin and the inorganic fine particles during mixing in the mixing unit. 5.   The molding unit includes a discharge unit that discharges the mixture, a mesh belt that deposits the mixture, and a suction unit that sucks the gas containing the mixture discharged through the mesh belt. The sheet manufacturing apparatus according to any one of claims 1 to 4.   The sheet manufacturing apparatus according to any one of claims 1 to 5, wherein the content of the inorganic fine particles in the composite is 0.1 mass% or more and less than 4 mass%.   7. The mixing unit according to claim 1, wherein the mixing unit includes a plurality of rotating units having rotating blades, and the fibers and the composite are mixed by passing through the rotating unit. The sheet manufacturing apparatus according to one item. Mixing a fiber, a composite of resin and inorganic fine particles, and mixing in air;
Depositing a mixture of the fibers and the composite, and heating and molding the mixture;
A sheet manufacturing method.

Images