JP2015183319A - Sheet production apparatus and sheet production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet production apparatus which can produce a sheet having a function different from that of a raw material when recycling is performed a plurality of times and a sheet production method.SOLUTION: A sheet production apparatus 120 has: a fibrillation unit 20 configured to fibrillate a raw material 1 comprising at least fibers; an addition unit 32 configured to add an additive to a fibrillated material that is fibrillated by the fibrillation unit 20; and a sheet formation unit 40 configured to form a sheet S by binding a plurality of fibers with each other through the additive. The sheet production apparatus 120 can produce a sheet S having a lower density in a case where the number of times the raw material 1 is recycled is more than that in a case where the number of times the raw material 1 is recycled is less.

Description

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

  2. Description of the Related Art Conventionally, in a sheet manufacturing apparatus, a so-called wet method is often employed in which a raw material containing fibers is introduced into water, disaggregated mainly by mechanical action, and re-made. A sheet manufactured by such a wet type sheet manufacturing apparatus has a structure in which, for example, cellulose fibers derived from wood or the like are entangled with each other and partially bound by a binding force such as hydrogen bonding.

  Further, as a method for producing a fiberboard using waste paper and paper waste such as pulp waste, screen waste, and cleaner waste generated when dissociating waste paper, as a raw material (pulp raw material), for example, Patent Document 1 discloses waste paper Dry defibrating material (fiber material) based on at least one of paper and papermaking waste such as plastic, 2-20% by weight of plastic on a dry basis, and dry paper or woody material on a dry basis There has been proposed a method in which a blended raw material blended so as to be contained at a ratio of 10 to 30% by weight is heated and pressurized to be molded into a predetermined shape.

  According to this method, when the fiberboard raw material contains plastic at a ratio such that the plastic content in the blended raw material exceeds the predetermined range, a part of the plastic in the fiberboard raw material is removed. When the fiberboard raw material contains plastic at a ratio such that the plastic content in the mixed raw material falls within the predetermined range, and the plastic content in the mixed raw material falls below the predetermined range, It is disclosed that a plastic is separately added so that a predetermined content ratio of the plastic in the blended raw material is within the range.

JP-A-10-121400

  However, it has not been proposed so far to produce a desired sheet by recycling waste paper a plurality of times.

  And it has not been proposed so far to manufacture sheets having different functions depending on the number of recycling.

  One of the objects according to some aspects of the present invention is to provide a sheet manufacturing apparatus and a sheet manufacturing method capable of manufacturing a sheet having a function different from that of a raw material when recycled a plurality of times.

  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.

(1) One aspect of the sheet manufacturing apparatus according to the present invention is:
A defibrating unit for defibrating at least raw materials containing fibers;
An additive part for adding an additive to the defibrated material defibrated in the defibrating part,
A sheet forming unit that forms a sheet by binding a plurality of fibers through the additive;
A sheet manufacturing apparatus comprising:
It is characterized in that a sheet having a lower density is produced when the number of times the raw material is recycled in the past is larger than when the number of times the material is recycled is smaller.

  According to such a sheet manufacturing apparatus, when recycling a plurality of times, a sheet having a function different from that of the raw material can be manufactured. When the raw material is recycled multiple times, deterioration of the fiber in the defibrated material is inevitable. However, even if the fiber is deteriorated by recycling a plurality of times as described above, according to such a sheet manufacturing apparatus, it is possible to further recycle into a low-density sheet having a function different from that of the raw material sheet.

(2) In the sheet manufacturing apparatus according to the present invention,
When the number of times of recycling is larger, a core-sheath resin may be added as the additive.

  According to such a sheet manufacturing apparatus, even if the number of times of recycling is larger and the number of fibers having a short fiber length is increased in the defibrated material, short fibers can be obtained by making the additive a resin of a core-sheath structure. Can be bound. Further, according to the resin having the core-sheath structure, the core part serves as a fiber, so that a short fiber can be supplemented.

(3) In the sheet manufacturing apparatus according to the present invention,
A pressurizing unit that pressurizes when forming the sheet;
The pressing force when the number of times of recycling is smaller may be larger than the pressing force when the number of times of recycling is large.

  According to such a sheet manufacturing apparatus, a sheet having a low density can be manufactured because the pressing force is smaller when the number of times of recycling is large.

(4) In the sheet manufacturing apparatus according to the present invention,
A marking part that performs marking indicating the number of times the raw material is recycled when manufacturing a sheet;
An acquisition unit for reading the marking and acquiring the number of times of recycling;
A control unit for controlling whether to manufacture a sheet having a high density or a sheet having a low density according to the acquired number of times of recycling; and
May further be included.

  According to such a sheet manufacturing apparatus, the number of times of recycling can be grasped by using the marking. Moreover, according to such a sheet manufacturing apparatus, it is possible to control the manufacture of sheets having different densities according to the acquired number of recycling times.

(5) One aspect of the sheet manufacturing method according to the present invention is:
Defibrating raw materials containing at least fibers,
Add additives to the defibrated defibrated material,
A method for producing a sheet by binding a plurality of fibers through the additive,
A sheet having a lower density is produced when the number of times the raw material is recycled is larger than when the number of times the material is recycled is smaller.

According to such a sheet manufacturing method, a sheet having a function different from that of the raw material can be manufactured when the sheet is recycled a plurality of times. When the sheet is recycled a plurality of times, deterioration of the fiber in the defibrated material is inevitable. However, even if the fiber is deteriorated by recycling a plurality of times as described above, according to such a sheet manufacturing method, it is possible to further recycle into a low-density sheet having a function different from that of the raw material sheet.

The figure which shows typically the sheet manufacturing apparatus which concerns on this embodiment. The functional block diagram which shows the sheet manufacturing apparatus which concerns on this embodiment. The table | surface which showed the additive etc. in each Example, and reproduction | regeneration.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are essential constituent requirements of the present invention.

  The sheet manufacturing apparatus according to the present embodiment includes a defibrating unit for defibrating at least a raw material containing fibers, an addition unit for adding an additive to the defibrated material defibrated by the defibrating unit, A sheet forming unit that forms a sheet by binding fibers together via the additive, and the number of times when the raw material is recycled more is more It is characterized in that a sheet having a smaller density than that in the case where the amount is small is manufactured.

  In this specification, in the sheet manufacturing apparatus, “upstream” with respect to the flow (including the conceptual flow) of the material (raw material 1, defibrated material, web W, sheet S, etc.) of the sheet to be manufactured. , “Downstream” and the like are used. The expression “upstream side (downstream side)” is used to relatively specify the position of the configuration. For example, when “A is on the upstream side (downstream side) of B”, A Is located upstream (downstream) with respect to the position B in the direction of material flow of the sheet S.

  Moreover, in this specification, dry means not in liquid but in the atmosphere (in the air). The dry category includes a dry state and a state where a liquid (such as water) present as an impurity or a liquid (water or the like) intentionally added, water vapor, mist, or the like is present. In addition, it should be noted that the amount of water used for the entire apparatus or the amount of paper produced is completely different between the dry mode and the wet mode performed by papermaking. That is, in the dry mode, the amount of water when water is present in the system is much smaller than that of wet type.

1. Sheet Manufacturing Apparatus The sheet manufacturing apparatus 120 according to the present embodiment adds an additive to the defibrating unit 20 that defibrates the raw material 1 including at least fibers and the defibrated material defibrated by the defibrating unit 20. And a sheet forming unit 40 that forms a sheet S by binding a plurality of fibers with additives. The sheet manufacturing apparatus 120 manufactures a sheet having a lower density when the number of times of recycling the sheet as the raw material 1 is larger than when the number of times of recycling is smaller. FIG. 1 is a schematic diagram schematically showing a sheet manufacturing apparatus 120 according to the present embodiment. Hereinafter, the sheet manufacturing apparatus 120 of the present embodiment will be described focusing on the defibrating unit 20 and the adding unit 32.

1.1. The defibrating unit The defibrating unit 20 defibrates the raw material 1 containing at least fibers. The defibrating unit 20 defibrates the raw material 1 to generate a defibrated material that has been unraveled into a fibrous form. The defibrating unit 20 also has a function of separating substances such as resin particles, ink, toner, and anti-bleeding agent adhering to the raw material 1 from the fibers when the raw material 1 is printed waste paper or the like.

Here, “defibration” means unraveling the raw material 1 formed by binding a plurality of fibers into one fiber. What has passed through the defibrating unit 20 is referred to as “defibrated material”. In the “defibrated material”, in addition to the unraveled fibers, resin particles separated from the fibers when the fibers are unraveled (resins for binding a plurality of fibers), and colorants such as ink and toner In some cases, additives such as an anti-bleeding material 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 is provided on the upstream side of the mixing unit 30 described later. Another configuration may be provided between the defibrating unit 20 and the mixing unit 30. Further, another configuration may be provided on the upstream side of the defibrating unit 20.

  The defibrating unit 20 is optional as long as it has a function of defibrating the raw material 1. The defibrating unit 20 defibrates in a dry manner in the atmosphere (in the air). In the illustrated example, the raw material 1 introduced from the introduction port 21 is defibrated by the defibrating unit 20 to become a defibrated material (fiber) and discharged from the discharge port 22.

  The configuration of the defibrating unit 20 is not particularly limited. For example, the defibrating unit 20 includes a rotating unit (rotor) and a fixing unit that covers the rotating unit, and a gap (gap) is formed between the rotating unit and the fixing unit. be able to. When the defibrating unit 20 is configured in this way, the defibrating process is performed by introducing the raw material 1 into the gap while the rotating unit is rotated. In this case, the number of rotations, the shape of the rotating part, the shape of the fixed part, and the like can be appropriately designed according to the requirements of the properties of the sheet S to be manufactured and the overall apparatus configuration. In this case, the rotation speed of the rotating part (number of rotations per minute (rpm)) is the throughput of the defibrating process, the residence time of the raw material, the degree of defibrating, the size of the gap, the rotating part, the fixed part, Other conditions such as the shape and size of each member can be set as appropriate.

  It is more preferable that the defibrating unit 20 has a function of generating an air flow that sucks the raw material 1 and / or discharges the defibrated material. In this case, the defibrating unit 20 can suck the raw material 1 together with the airflow from the introduction port 21 by the airflow generated by itself, defibrate, and transport the raw material 1 to the discharge port 22. The defibrated material discharged from the discharge port 22 is transferred to the pipe 82 in the example shown in FIG. In addition, when using the defibrating part 20 which does not have an airflow generation mechanism, the mechanism which generate | occur | produces the airflow which draws the defibrated material from the airflow which guide | induces the raw material 1 to the inlet 21 and the discharge port 22 is attached externally It can be provided.

  In the present embodiment, the defibrated material discharged from the discharge port 22 is supplied by the switching valve 25 to the mixing unit 30 through the pipe 82 and the classification unit 63 and the selection unit 35. And the second path that is directly supplied to the mixing unit 30 through the pipe 85. In the present embodiment, in particular, the sheet S can be manufactured using the second path.

  When the second path is selected by the switching valve 25, (1) since the defibrated material is sent directly from the defibrating unit 20 to the mixing unit 30, the length of the fibers is made uniform as a function of the sheet S. There are cases where a low-demand sheet S is manufactured, and (2) a sheet S that does not affect the function even if resin particles or ink particles generated by defibrating are mixed with the sheet S. In these cases, a sheet S having a function different from that of the raw material 1 may be produced from the raw material 1, for example, a liquid absorption such as a nonwoven fabric in which the raw material 1 is paper and the sheet S is smaller in density than paper. It may be a material or a sound absorbing material.

When the first route is selected, the classifying unit 63 and the sorting unit 35 transfer only a sheet having a predetermined size or less to the sheet forming unit 40 in accordance with the use and function of the sheet S intended for defibrated material. This is the case. Here, an example in which the second path is selected using the switching valve 25 will be described, but the switching valve 25 is not used even when the sheet 1 having a function different from that of the raw material 1 is manufactured. The first route may always be passed.

1.1.1. Raw material In this specification, the raw material 1 refers to an article containing the raw material of the sheet manufacturing apparatus 120, for example, pulp sheet, paper, waste paper, tissue paper, kitchen paper, cleaner, filter, liquid absorber, sound absorber , A cushioning material, mat, cardboard, or the like, in which fibers are intertwined or bound. Raw material 1 includes rayon, lyocell, cupra, vinylon, acrylic, nylon, aramid, polyester, polyethylene, polypropylene, polyurethane, polyimide, carbon, glass, fibers made of metal, etc. (organic fiber, inorganic fiber, organic-inorganic composite) Fiber). Here, what was recycled several times can be used as the raw material 1, and especially waste paper can be used effectively.

  The raw material 1 may have a history. The history of the raw material 1 is information on the properties of the raw material 1, and specifically, the content of the additive in the raw material 1, the type of the additive in the raw material 1, the fiber length in the raw material 1, the material of the fiber in the raw material 1, etc. Can be mentioned. Information for easily obtaining information on the properties of the raw material 1 corresponds to the number of times the sheet is recycled to another sheet S as the raw material 1 (hereinafter simply referred to as “the number of times of recycling”). Information, information corresponding to the type of the sheet S (paper, pulp sheet, waste paper, etc.), information on the sheet manufacturing apparatus used for recycling, and the like can be mentioned. These pieces of information are grasped by the marking given to the sheet S. The sheet manufacturing apparatus 120 includes a marking unit 100 that applies a marking to the sheet S on the downstream side of the sheet forming unit 40 or the sheet forming unit 40. In addition, the sheet manufacturing apparatus 120 includes an acquisition unit 8 that acquires the history of the raw material 1 by reading the marking given to the raw material 1. The marking unit 100 and the acquisition unit 8 will be described later.

  The number of times of recycling is the number of times the raw material 1 is recycled to the sheet S in the sheet manufacturing apparatus 120. Hereinafter, it may be simply indicated by “the number of times of recycling”. Since the paper manufactured by the wet method is not recycled by the sheet manufacturing apparatus 120, the number of times of recycling is zero. When the sheet S is manufactured using the paper manufactured by the wet method as the raw material 1, the number of times of recycling is one. In addition, when the sheet S having the recycle count of 1 is used as the raw material 1 and the sheet S is manufactured in the sheet manufacturing apparatus 120, the recycle count is 2 times. Even if the sheet is not manufactured by the sheet manufacturing apparatus 120, it is included in the number of recycling if the sheet manufacturing apparatus 120 can grasp the number of recycling. Whether or not the sheet manufacturing apparatus 120 can grasp the number of times of recycling depends on whether or not the history of the raw material can be acquired by the acquisition unit 8. For example, even if the paper manufactured by recycling wet paper using raw paper as raw material is raw material 1, if there is no marking or if it cannot be grasped by the sheet manufacturing apparatus 120, the property of raw material 1 cannot be grasped. Is not considered one time. In such a case, the number of times of recycling is grasped as 0 and included in the information corresponding to the number of times of recycling as the number of times of recycling. The raw material 1 that has not yet been recycled by the sheet manufacturing apparatus 120 has been recycled 0 times.

  The marking to be given to the sheet S is not only characters indicating the type of the sheet S, the number of times of recycling and the type itself, but also marks such as marks and symbols having other forms as long as the number of times of recycling and type are known. May be. For example, if the marking is “◯”, the density may be reduced. The information corresponding to the number of times of recycling may be not only the number of times of recycling but also information indicating whether or not to manufacture by changing the conditions next.

  The sheet manufacturing apparatus 120 can vary the amount, type, and the like of the additive to be added to the raw material 1 by the addition unit 32 based on the history of the raw material 1.

1.1.2. Defibrated material In the sheet manufacturing apparatus 120 of the present embodiment, the defibrated material used as part of the material of the sheet to be produced is not particularly limited, and a wide range of defibrated material can be used as long as the sheet can be formed. Can do. The defibrated material includes fibers obtained by defibrating the above-described raw material 1, and as such fibers, natural fibers (animal fibers, plant fibers), chemical fibers (organic fibers, inorganic fibers, organic-inorganic composite fibers), etc. Is mentioned. More specifically, the fibers contained in the defibrated material include cellulose fibers made of cotton, cannabis, kenaf, flax, ramie, jute, manila hemp, sisal hemp, conifers, hardwood, etc., and animal fibers such as silk and wool. These may be used singly, or may be used by appropriately mixing them, or may be used as regenerated fibers that have been subjected to purification or the like. The defibrated material becomes the material of the sheet S to be manufactured, but it is sufficient that it contains at least one of these fibers. In addition, the defibrated material (fiber) may be dried, or may be contained or impregnated with a liquid such as water or an organic solvent. Furthermore, the defibrated material (fiber) may be subjected to various surface treatments.

  The defibrated material has various properties according to the history of the raw material 1. As the properties of the defibrated material, for example, (1) when the raw material 1 is not recycled yet, the defibrated material contains no resin as an additive, and (2) the raw material 1 is recycled one or more times. In the case of the sheet S that has been subjected to the process, a resin adheres to the defibrated material, and (3) in the case of the sheet S in which the raw material 1 has been recycled two or more times, the defibrated material is more defibrated. For example, a fiber having a short length is included.

  In the defibrated material used in the present embodiment, more additives adhere to the defibrated material when the raw material 1 is recycled more frequently than when the raw material 1 is recycled fewer times. ing. In addition, when the number of times of recycling is larger in this way, the fibers of the defibrated material are more short fibers.

  When the fibers contained in the defibrated material used in the present embodiment are independent fibers, the average diameter (if the cross section is not a circle, the length in the direction perpendicular to the longitudinal direction) Among these, the diameter of the circle when assuming the largest one or a circle having an area equal to the area of the cross section (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, it is 3 μm or more and 200 μm or less.

  The length of the fiber contained in the defibrated material used in the present embodiment is not particularly limited, but as an independent single fiber, the length along the longitudinal direction of the fiber (the defibrated material that has been unraveled) The length of the (fiber) in the longitudinal direction (hereinafter also referred to as “fiber length”) is, for example, 1 μm to 10 mm, preferably 1 μm to 5 mm, and more preferably 3 μm to 2 mm. When the fiber length is short, the strength of the sheet may be insufficient, but a sheet having sufficient strength can be obtained within the above range. The length along the longitudinal direction of the fiber refers to the distance between the two ends of an independent single fiber when it is pulled without breaking as necessary and placed in a substantially linear state (the fiber length). Length). 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. Furthermore, the length of the fiber may have variation (distribution).

  In this specification, when referring to a fiber, it may refer to a single fiber and may refer to an aggregate of a plurality of fibers (for example, a state like cotton), and when referred to as a defibrated material, It refers to a material containing a plurality of fibers, and includes the meaning of a collection of fibers and the meaning of a material (powder or cotton-like object) that is a raw material of a sheet.

1.2. Mixing Unit Since the adding unit 32 provided in the sheet manufacturing apparatus 120 of the present embodiment is provided in the mixing unit 30, the mixing unit 30 will be described first. The adding unit 32 may be independent from the mixing unit 30 or may be disposed upstream of the mixing unit 30. The mixing unit 30 has a function of mixing (mixing) the defibrated material and the additive in the air.

  In the present specification, “mixing the defibrated material and the additive” means that the additive is positioned between the fibers contained in the defibrated material within a space (system) having a constant volume. To do.

  As long as the mixing part 30 can mix a defibrated material (fiber) and an additive, the structure, structure, mechanism, etc. will not be specifically limited. Further, the mode of the mixing process in the mixing unit 30 may be batch processing (batch processing), sequential processing, or continuous processing. The mixing unit 30 may be operated manually or automatically. Furthermore, although the mixing part 30 mixes at least a defibrated material and an additive, the aspect which can mix another component may be sufficient.

  The mixing unit 30 is provided on the downstream side of the defibrating unit 20 described above. The mixing unit 30 is provided on the upstream side of a sheet forming unit 40 described later. Between the defibrating unit 20 and the mixing unit 30, configurations such as a classification unit 63 and a sorting unit 35 may be included.

  Examples of the mixing process in the mixing unit 30 include mechanical mixing and hydrodynamic mixing. For mechanical mixing, the fiber (defibrated material) and additives are introduced into, for example, a Henschel mixer and stirred, or the bag (fiber defibrated material) and additives are enclosed in a bag. The method of shaking is mentioned. In addition, as a hydrodynamic mixing process, a method of introducing fibers (defibrated material) and additives into an air stream such as the atmosphere and diffusing each other in the air stream can be used. In the method of introducing fibers (defibrated material) and additives into the airflow such as the atmosphere, the additives may be introduced into a pipe or the like in which the fibers of the defibrated material are flowing (transferred) by the airflow, Fibers (defibrated material) may be introduced into a tube or the like in which additive particles are flowed (transferred) by an air flow. In the case of such a method, it is more preferable that the airflow in the pipe or the like is turbulent because mixing efficiency may be improved.

  As shown in FIG. 1, when the pipe 86 is used as the mixing unit 30 for transferring the defibrated material, the additive is added by the adding unit 32 in a state where the defibrated material is flowed by an air flow such as the atmosphere. The method of introduction can be taken. Examples of the airflow generating means in the case where the pipe 86 is employed in the mixing unit 30 include a blower (not shown), and any appropriate airflow generating means can be used as long as the above functions are obtained.

  In the sheet manufacturing apparatus 120 of the present embodiment, the mixing unit 30 is a dry type. Here, “dry” in mixing refers to a state of mixing in the atmosphere (in the air), not in the liquid. In the mixing unit 30, when the liquid is intentionally added to such an extent that the action of mixing is not hindered, the energy and time for removing the liquid by heating or the like in a later step are not increased so much. It is preferable to do.

The processing capacity of the mixing unit 30 is not particularly limited as long as the defibrated material and the additive can be mixed, and can be appropriately designed and adjusted according to the manufacturing capacity (throughput) of the sheet manufacturing apparatus 120. Adjustment of the processing capacity of the mixing unit 30 can be performed by changing the size of the processing container, the charged amount, etc., as long as it is a batch processing mode. When the part 32 is adopted, it can be performed by changing the flow rate of gas for transferring the defibrated material and additives in the tube 86, the amount of material introduced, the amount transferred, and the like. In addition, also when employ | adopting the pipe 86 and the addition part 32 like illustration as a mixing part 30, a defibrated material and an additive can fully be mixed.

1.2.1 Additive Part The mixing part 30 is referred to as an additive other than additives and additives (hereinafter referred to as “additives”) that bind fibers to the defibrated material defibrated by the defibrating part 20. ) Is added. The addition unit 32 may be charged so that the amount and type of additives and the like differ from the raw material 1 depending on the history of the raw material 1 supplied to the defibrating unit 20. The addition unit 32 may include a feeder that introduces an additive or the like into the flow path of the defibrated material.

  The introduction of an additive or the like (including the case of a composite) when the pipe 86 is employed in the mixing unit 30 can be performed by opening / closing the valve or by the operator's hand. 1 and a disk feeder (not shown). Use of these feeders is more preferable because fluctuations in the amount of additive added in the airflow direction can be reduced. The same applies to the case where additives and the like are transferred by an air stream and the defibrated material is introduced into the air stream. In the illustrated example, additives and the like are supplied to the pipe 86 through the supply ports 31 provided in the pipe 86 from a plurality of screw feeders (first and second additive input sections 32a and 32b) of the addition section 32. The Therefore, in the illustrated example, the mixing unit 30 is configured by a part of the pipe 86, the addition unit 32, and the supply port 31.

  Here, components other than the additive that can be supplied from the adding unit 32 may be, for example, a material that can impart the performance required for the sheet S to the defibrated material. Examples of components other than additives include fibers, aggregation inhibitors, colorants, flame retardants, organic solvents, surfactants, antifungal agents / preservatives, antioxidants, ultraviolet absorbers, oxygen absorbers, and the like. be able to.

  By using a plurality of screw feeders, the additive and other components can be supplied to the mixing unit 30 in accordance with the history of the raw material 1 or in order to satisfy the required performance of the sheet S. .

  Hereinafter, an example in which an additive is introduced into the pipe 86 from the first additive introduction part 32a and a flame retardant is introduced from the second additive introduction part 32b will be described.

1.2.1.1. Additive The additive supplied from the addition unit 32 binds a plurality of fibers included in the defibrated material. As the additive, a resin, starch (especially in the case of a wet type), and a water-soluble binder can be used. Moreover, the additive may contain the component of the component to bind.

  An appropriate amount of the additive can be supplied from the addition unit 32 to the defibrated material. The amount of additive added to the raw material 1 by the addition unit 32 varies depending on the history of the raw material 1. For example, when the sheet S is recycled twice, the amount of the additive contained in the defibrated material is different every time it is recycled, but by changing the amount of the additive according to the history of the raw material 1, Additives can be in desired amounts.

  The amount of additive to be added can be reduced in the case of the raw material 1 that has been recycled more frequently than in the case of the raw material 1 that has been recycled fewer times. By doing in this way, even if it uses as the raw material 1 with many frequency | counts of recycling, it can suppress that an additive becomes excessive.

Also, just because the sheet S has already been recycled, simply reducing the amount of additive evenly reduces the amount of additive in the sheet S that has been recycled multiple times. You may change the addition amount of an additive according to the frequency | count.

1.2.1.1.1. The additive that binds the resin fibers may contain a resin. The type of resin may be either a natural resin or a synthetic resin. In the sheet manufacturing apparatus 120 of the present embodiment, the resin is preferably solid at room temperature, and is a synthetic resin whose melting point and the like are adjusted to a predetermined range in order to obtain stable performance of the manufactured sheet S. It is preferable that a thermoplastic resin is more preferable when used for binding the fibers by heat in the heating unit 50.

  The resin includes a resin for binding a plurality of fibers. When the additive is supplied to the pipe 86, the plurality of fibers included in the defibrated material are not intentionally bound to each other unless the defibrating is insufficient. The resin contained in the additive melts or softens when passing through the heating unit 50 described later, and then binds the plurality of fibers by curing.

  Moreover, when the raw material 1 is the recycled sheet | seat S, resin for binding a some fiber remains in a defibrated material, and a part has adhered to the fiber. In such a case, an appropriate amount of resin is added from the addition section 32 in addition to the resin adhering to the fibers so that the sheet S having the desired amount of resin in the sheet S can be produced. Can do.

  Therefore, the amount of resin in the sheet S is appropriately set according to the history of the raw material 1 and the type of the sheet S to be manufactured. The ratio of the resin in the sheet S is, for example, 5% by mass or more and 70% by mass or less. In view of obtaining a good mixture in the mixing unit 30, the additive falls due to gravity when the mixture is formed into a web shape. From the viewpoint of making it difficult, it is preferably 5% by mass or more and 50% by mass or less. In the example shown in the figure, the supplied additive is mixed with the defibrated material in the pipe 86 constituting the mixing unit 30.

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

  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, Polyacetal, polyphenylene sulfide, polyether ether ketone and the like can be mentioned.

  These resins may be used alone or in combination. 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.

The additive may be in the form of a fiber or powder. When the additive is fibrous, the fiber length of the additive is preferably equal to or less than the fiber length of the defibrated material, but may be longer than the fiber length of the defibrated material as long as it can be mixed with the defibrated material. Good. Specifically, the fiber length of the additive is 5 mm or less. If the fiber length of the additive is greater than 5 mm, it may be difficult to stably supply the additive in the addition part 32 or to mix with the defibrated material with good uniformity. When the additive is in powder form, the particle size (diameter) of the additive is 1 μm to 100 μm, more preferably 2 μm to 80 μm. When the particle size of the additive is smaller than 1 μm, the binding force that binds the fibers in the defibrated material may decrease. If the particle size of the additive is larger than 80 μm, it may be difficult to mix with the defibrated material with good uniformity, and the adhesion to the defibrated material will be reduced and will be detached from the defibrated material. In some cases, unevenness or the like may occur in the applied sheet.

  When the number of times of recycling is larger, the additive may be a resin having a core-sheath structure. When the number of times of recycling is larger, the fiber length of the defibrated material tends to be short, and short fibers can be bound more reliably by adding a resin having a core-sheath structure. The resin with the core-sheath structure is effective as a structural material in the sheet S because the long core portion comes into contact with and binds to many fibers of the defibrated material. Further, according to the resin having the core-sheath structure, the core part serves as a fiber, so that a short fiber can be supplemented.

  The resin of the core-sheath structure has a fibrous form in which the outer surface of the elongated core part formed of resin is covered with the sheath part formed of another resin. The melting point of the resin in the core part is higher than the melting point of the resin in the sheath part, and when heated by the sheet forming part 40 described later, only the sheath part melts and binds the fibers of the defibrated material. And a core part exists in the sheet | seat S, keeping the form of a fiber, and can play the role which supplements the short fiber in the sheet | seat S. FIG. Examples of the core / sheath resin combination include polypropylene / polyethylene, polyester / polyethylene, high-melting polypropylene / low-melting polypropylene, polyester / polypropylene, and polyamide / polyethylene.

  In addition, in order to supplement short fibers without using a core-sheath structure resin, for example, another defibrated material having a sufficiently long fiber length may be introduced from the addition portion 32.

1.2.1.2. Flame retardant A flame retardant may be charged from the second additive charging portion 32b. A flame retardant is for making a fiber etc. hard to burn.

  Any known flame retardant material can be used as the flame retardant. Various flame retardants such as halogen-based, phosphorus-based and nitrogen-based flame retardants can be used.

  Examples of phosphorus-based materials include phosphate esters and melamine phosphate. Phosphate esters include phosphates, phosphonates, trimethyl phosphates of phosphinates, triethyl phosphate, tributyl phosphate, trioctyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, octyl diphenyl phosphate, tricresyl phosphate, Cresyl diphenyl phosphate, triphenyl phosphate, trixylenyl phosphate, tris-isopropylphenyl phosphate, diethyl-N, N-bis (2-hydroxyethyl) aminomethylphosphonate, bis (1,3-phenylenediphenyl) Phosphate, aromatic condensed phosphate ester 1,3- [bis (2,6-dimethylphenoxy) phosphenyloxy] benzene, 1,4- [bis 2,6-dimethyl-phenoxy) phosphite phenyl oxy] benzene.

  Examples of phosphorus inorganic phosphorus compounds include red phosphorus compounds and ammonium polyphosphate. Examples of red phosphorus compounds include red phosphorus coated with a resin, and composite compounds with aluminum.

  Nitrogen includes compounds having a triazine group and / or derivatives thereof, and specific examples include melamine, melamine cyanurate, melamine phosphate, melamine polyphosphate, guanidine sulfamate and the like.

Phosphazene, antimony trioxide, antimony tetroxide, antimony pentoxide, sodium pyroantimonate, tin dioxide, zinc metaborate, aluminum hydroxide, magnesium hydroxide, zirconium oxide, molybdenum oxide, red phosphorus compound, ammonium polyphosphate Examples thereof include salts, melamine cyanurate, and tetrafluoroethylene.

  It should be noted that the flame retardant is effective for applications where the ambient temperature is high, for example, a liquid absorber or a sound absorber used in an ink jet printer, but may not be added in other cases. .

1.2.1.3. Aggregation inhibitor The additive may include an aggregation inhibitor for suppressing aggregation of fibers in the defibrated material and aggregation of resins in the additive, in addition to the resin that binds the defibrated material. Moreover, when an aggregation inhibitor is included in the additive, it is preferable to integrate the resin and the aggregation inhibitor. That is, when the aggregation inhibitor is included in the additive, the additive is preferably a composite body integrally including the resin and the aggregation inhibitor.

  Specific examples of the material for the aggregation inhibitor include silica, titanium oxide, aluminum oxide, zinc oxide, cerium oxide, magnesium oxide, zirconium oxide, strontium titanate, barium titanate, and calcium carbonate. A part of the material of the exemplified aggregation inhibitor (for example, titanium oxide) is the same as the material of the colorant, but the particle diameter of the aggregation inhibitor is different in that it is smaller than the particle diameter of the colorant. Therefore, the aggregation inhibitor does not greatly affect the color tone of the produced sheet and can be distinguished from the colorant. However, when adjusting the color tone of the sheet, even if the particle size of the aggregation inhibitor is small, some effects such as light scattering may occur, so it is more preferable to consider such effects.

1.2.1.4. The colorant additive may contain a colorant in addition to the resin that binds the fibers of the defibrated material. Moreover, when a colorant is included in the additive, the resin and the colorant are preferably integrated. That is, the additive is preferably a composite that integrally includes a resin and a colorant. Further, even when the composite includes the above-described aggregation inhibitor, it can be a composite that integrally includes the resin, the colorant, and the aggregation inhibitor. That is, the additive may include a composite that integrally includes a resin, an aggregation inhibitor, and a colorant.

  The coloring material has a function of setting a predetermined color of the sheet manufactured by the sheet manufacturing apparatus 120 of the present embodiment. As the colorant, a dye or a pigment can be used, and it is preferable to use a pigment from the viewpoint of obtaining better hiding power and color developability when the composite is integrated with a resin.

  The color and type of the pigment are not particularly limited, and various colors used in general inks (white, blue, red, yellow, cyan, magenta, yellow, black, special colors (pearl, metallic luster) Etc.) can be used. The pigment may be an inorganic pigment or an organic pigment. As the pigment, known pigments described in JP 2012-87309 A and JP 2004-250559 A can be used. In addition, white pigments such as zinc white, titanium oxide, antimony white, zinc sulfide, clay, silica, white carbon, talc, and alumina white may be used. These pigments may be used singly or may be used in combination as appropriate. In the case of using a white pigment, among those exemplified above, it is possible to use a pigment made of powder containing particles mainly composed of titanium oxide (pigment particles). From the viewpoint of easily increasing the whiteness of the sheet to be produced with a small blending amount, it is more preferable.

1.2.1.5. Water-soluble binder In the case of the wet method, a water-soluble binder can be used as an additive. Examples of the water-soluble binder include polyacrylamide, polyamide epichlorohydrin, polyvinyl alcohol, starch, and alkyl ketene dimer. The water-soluble binder is sometimes called a paper strength enhancer.

1.2.1.6. Components other than the additive supplied from the fiber addition unit 32 may include fibers. As a kind of fiber, a fiber required in order to obtain the desired sheet | seat S from the fiber mentioned above in "1.1.1. Raw material" can be selected suitably. The fiber may be the same type of fiber as the fiber contained in the raw material 1 or may be a different type of fiber. Further, the fiber may have a higher fiber strength or a longer length than the fiber contained in the raw material 1. Alternatively, it may be a fiber obtained by defibrating the raw material 1 that is recycled zero times. By selecting such fibers, the strength of the sheet S can be reinforced.

1.3. Sheet Forming Unit The sheet forming unit 40 forms a sheet S by binding a plurality of fibers with additives.

  In the mixture in which the additive is mixed with the defibrated material in the mixing unit 30, the fibers are bound to each other via the additive in the sheet forming unit 40 to form the sheet S.

  In this specification, the sheet S refers to a structure in which a plurality of fibers are two-dimensionally or three-dimensionally bound to each other via a resin or by hydrogen bonding.

  The sheet S in the present specification is not limited to a sheet shape, and may be a film shape, a board shape, a web shape, or an uneven shape. The sheet S 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 the raw material 1 and is formed into a sheet, 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.

  The sheet S has a lower density when it is recycled more than when it is recycled less. Therefore, when the waste paper recycled a plurality of times is used as the raw material 1, the sheet S obtained by the sheet forming unit 40 is a non-woven fabric or a liquid absorbent material having a density lower than that.

  The sheet forming unit 40 can include, for example, a deposition unit 75, a pressurizing unit 60, a heating unit 50, and a cutting unit 90. These will be described later.

1.4. Effects According to the sheet manufacturing apparatus 120 of the present embodiment, a sheet S having a function different from that of the raw material 1 can be manufactured when being recycled a plurality of times.

  When the number of times of recycling increases, the fibers constituting the raw material 1 deteriorate and become shorter, and it becomes gradually difficult to regenerate into a sheet having the same function as the sheet S used as the raw material 1. For example, although the strength of the sheet S can be maintained by increasing the amount of the additive that binds the fibers even when the fiber is shortened, if the additive is excessive, the texture as paper becomes difficult to obtain.

  By manufacturing the sheet S having a low density as in the present embodiment, even if the fibers constituting the raw material 1 are shortened, they can be further regenerated.

1.5. Other Configurations Other configurations of the sheet manufacturing apparatus 120 will be described with reference to FIGS. 1 and 2. FIG. 2 is a functional block diagram showing the sheet manufacturing apparatus 120 according to the present embodiment.

  In addition to the above-described defibrating unit 20, mixing unit 30, and sheet forming unit 40, the sheet manufacturing apparatus 120 of the present embodiment includes an acquisition unit 8, a supply unit 9, a crushing unit 10, a classification unit 63, a sorting unit 35, Various configurations such as the marking unit 100 and the control unit 110 can be included. The mixing unit 30 can include a loosening unit 70 in addition to the addition unit 32 described above. Further, the sheet forming unit 40 can include various configurations such as a deposition unit 75, a pressure unit 60, a heating unit 50, and a cutting unit 90. Each of these configurations will be described below. The acquisition unit 8, the supply unit 9, the crushing unit 10, the defibrating unit 20, the classification unit 63, the sorting unit 35, the mixing unit 30, the loosening unit 70, the sheet forming unit 40, the deposition unit 75, the pressurizing unit 60, A plurality of configurations of the heating unit 50, the cutting unit 90, the marking unit 100, and the like may be provided as necessary.

1.5.1. Acquisition Unit The sheet manufacturing apparatus 120 of the present embodiment may include the acquisition unit 8. The acquisition unit 8 acquires the history of the raw material 1. The acquisition unit 8 acquires various histories that can be read from the raw material 1. Regarding the history, there are various types of information described in “1.1.1. Raw Material”, but the acquisition unit 8 has means for reading these various types of information. For example, the acquisition unit 8 may acquire the history of the raw material 1 by reading the marking applied to the sheet S in the marking unit 100 described later. The acquisition unit 8 is an optical sensor, for example, and emits light to the marking and receives the reflected light to read the marking.

  In the sheet manufacturing apparatus 120 illustrated in FIG. 1, the sheet manufacturing apparatus 120 is disposed upstream of the defibrating unit 20 and at a position where the raw material 1 is supplied to the sheet manufacturing apparatus 120. The history of the raw material 1 acquired by the acquisition unit 8 is output to the control unit 110.

1.5.2. Supply Unit The sheet manufacturing apparatus 120 of the present embodiment may include the supply unit 9. In the sheet manufacturing apparatus 120 shown in FIG. 1, it arrange | positions in the upstream of the defibrating part 20, and supplies the raw material 1 to the downstream. The supply unit 9 may supply the raw material 1 to the crushing unit 10.

  The supply unit 9 may be an automatic input device for continuously supplying the raw material 1 to the crushing unit 10.

  Based on the history of the raw material 1 acquired by the acquisition unit 8, the supply unit 9 sorts the raw material 1 into a plurality of types having the same level of history according to a command from the control unit 110, and stores them for each type. You may supply to the crushing part 10. FIG. When a plurality of raw materials 1 are continuously supplied from the supply unit 9, the same kind of additives and the like are supplied in the same amount by continuously supplying the raw materials 1 having the same history to the downstream. The sheet S having the same performance can be manufactured continuously. Further, when the raw material 1 is supplied from the supply unit 9 one by one, the amount and type of additives and the like can be made different for each raw material 1, and a desired sheet S can be manufactured.

1.5.3. Crushing Unit The sheet manufacturing apparatus 120 of the present embodiment may include the crushing unit 10. In the sheet manufacturing apparatus 120 illustrated in FIG. 1, the crushing unit 10 is disposed on the upstream side of the defibrating unit 20. The crushing unit 10 cuts the raw material 1 such as a pulp sheet or a charged sheet (for example, A4-sized waste paper) in the air to make a material to be defibrated. Although the shape and size of the material to be defibrated are not particularly limited, for example, it is cut to several cm square. In the illustrated example, the crushing unit 10 has a crushing blade 11, and the charged raw material 1 can be cut by the crushing blade 11.

  A specific example of the crushing unit 10 is a shredder. In the illustrated example, the defibrated material cut by the crushing unit 10 is received by the hopper 15 and then conveyed to the defibrating unit 20 via the pipe 81. The tube 81 communicates with the introduction port 21 of the defibrating unit 20.

1.5.4. Classification Unit In the sheet manufacturing apparatus 120 shown in FIG. 1, a classification unit 63 is disposed on the upstream side of the mixing unit 30 and on the downstream side of the defibrating unit 20. When the first path is selected by the switching valve 25, the defibrated material is introduced into the classifying unit 63. Switching of the switching valve 25 can be performed by a command from the control unit 110 according to the history of the raw material 1 acquired by the acquisition unit 8. When the sheet S having a density lower than that of the raw material 1 is formed and the second path is selected by the switching valve 25, the defibrated material does not pass through the classification unit 63 and the selection unit 35. The classifying unit 63 separates and removes relatively small items, low-density additives, resin particles, ink particles, and the like contained in the raw material 1 from the defibrated material. Thereby, the ratio for which the fiber which is a comparatively large thing or a thing with a high density in a defibrated material can be raised.

  As the classification unit 63, it is preferable to use an airflow classifier. The airflow classifier generates a swirling airflow and separates it by the difference between the centrifugal force and the centrifugal force received depending on the size and density of what is classified, and adjusts the classification point by adjusting the velocity and centrifugal force of the airflow be able to. Specifically, a cyclone, elbow jet, eddy classifier, or the like is used as the classifying unit 63. In particular, since the structure of the cyclone is simple, it can be suitably used as the classification unit 63. Below, the case where a cyclone is used as the classification part 63 is demonstrated.

  The classifying unit 63 includes an introduction port 64, a cylindrical unit 65 to which the introduction port 64 is connected, an inverted conical unit 66 located below the cylindrical unit 65 and continuing to the cylindrical unit 65, and a lower part of the inverted cone unit 66. A lower discharge port 67 provided in the center and an upper discharge port 68 provided in the upper center of the cylindrical portion 65 are provided.

  In the classifying unit 63, the airflow on which the defibrated material introduced from the introduction port 64 is placed is changed into a circumferential motion by the cylindrical unit 65. As a result, the introduced defibrated material is subjected to centrifugal force, and the defibrated material is larger in density than the resin particles and ink particles, and the defibrated material is smaller in density than the fibers. It can be separated into low resin particles and ink particles. The component having a large amount of fiber is discharged from the lower discharge port 67 and introduced into the sorting unit 35 through the pipe 83. On the other hand, resin particles and ink particles are discharged from the upper discharge port 68 through the tube 84 to the outside of the classification unit 63. In the illustrated example, the tube 84 is connected to the receiving portion 69, and fine powder is collected in the receiving portion 69.

  In addition, although described that it isolate | separates into a fiber and a fine powder by the classification part 63, it cannot isolate | separate completely. For example, relatively small or low density fibers may be discharged to the outside together with fine powder. Further, fine powder having a relatively high density or entangled with the fiber may be introduced into the sorting unit 35 together with the fiber.

  Further, when the raw material is not waste paper but a pulp sheet, since the fine powder such as resin particles and ink particles is not included, the sheet manufacturing apparatus 120 may not include the classification unit 63. Conversely, when the raw material is used paper, the sheet manufacturing apparatus 120 is preferably configured to include the classification unit 63 in order to improve the color tone of the manufactured sheet S. In addition, since paper is often required to have better whiteness than non-woven fabric, it is better to have a classifying unit 63 when manufacturing paper, and when manufacturing non-woven fabric, classifying unit 63 is There may be no need.

1.5.5. Sorting Unit The sheet manufacturing apparatus 120 according to the present embodiment may include a sorting unit 35. The sorting unit 35 can sort the defibrated material that has been defibrated in the defibrating unit 20 according to the length of the fiber. In addition, although the above-mentioned classification | category part 63 described that fine resin powder etc. were removed, the selection part 35 may have such a function. Accordingly, the sorting unit 35 is provided downstream of the defibrating unit 20 and upstream of the loosening unit 70.

  As the selection unit 35, a sieve can be used. Here, the sorting unit 35 has a net (filter, screen), and sorts out a size that can pass through the net and a size that cannot pass through the net. The sorting unit 35 has an introduction port 36 and a discharge port 37. Although the selection part 35 can be comprised similarly to the unwinding part 70 mentioned later, it has the function to remove one part component rather than letting all the introduced materials pass like the unraveling part 70. FIG. An example of the sorting unit 35 is a cylindrical sieve that can be rotated by a motor. As the net of the sorting unit 35, 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 can be used.

  By providing the sorting unit 35, fibers or particles smaller than the size of the mesh openings included in the defibrated material or mixture, and fibers, undefibrated pieces, and lumps larger than the size of the mesh openings are separated. Can do. The selected substance can be selected and used according to the sheet S to be manufactured. The defibrated material that has passed through the sieve of the sorting unit 35 is received by the hopper 38 and then conveyed to the introduction port 71 of the loosening unit 70 via the pipe 86 of the mixing unit 30. In addition, the substance removed by the sorting unit 35 may be returned to the crushing unit 10 from the discharge port 37.

1.5.6. Loosening part The sheet manufacturing apparatus 120 may have the loosening part 70. In the sheet manufacturing apparatus 120 illustrated in FIG. 1, a loosening unit 70 and a deposition unit 75 are disposed downstream of the addition unit 32. In FIG. 2, the loosening unit 70 is included in the mixing unit 30 together with the adding unit 32.

  The loosening unit 70 introduces the mixture that has passed through the pipe 86 of the mixing unit 30 from the introduction port 71 and lowers the mixture while dispersing it in the air. Further, in this example, the sheet manufacturing apparatus 120 includes a stacking unit 75, and in the stacking unit 75, the mixture falling from the loosening unit 70 is deposited in the air and formed into the shape of the web W. It has become.

  The loosening part 70 loosens the entangled defibrated material (fiber). Further, the loosening unit 70 loosens the entangled resin when the additive resin supplied from the addition unit 32 is fibrous. Moreover, the loosening part 70 has the effect | action which deposits a mixture uniformly on the deposition part 75 mentioned later. In other words, the term “unwind” includes the action of breaking up intertwined things and the action of depositing them uniformly. The loosening portion 70 has an effect of being uniformly deposited if there is no entanglement.

  As the loosening portion 70, a sieve is used. An example of the loosening unit 70 is a rotary sieve that can be rotated by a motor. Here, the “sieving” of the loosening unit 70 may not have a function of selecting a specific object. That is, the “sieving” used as the loosening part 70 means a thing provided with a net (filter, screen), and the loosening part 70 is all of the defibrated material and additives introduced into the loosening part 70. May be dropped.

1.5.7. Deposition Unit The sheet manufacturing apparatus 120 may include a deposition unit 75. The defibrated material and the additive that have passed through the loosening portion 70 are deposited on the deposition portion 75. As illustrated in FIG. 1, the accumulation unit 75 includes a mesh belt 76, a stretching roller 77, and a suction mechanism 78. The deposition unit 75 may include a tension roller (not shown).

  The depositing part 75 forms a web W in which the mixture falling from the loosening part 70 is deposited in the air (corresponding to the loosening part 70 and corresponding to the web forming step). The depositing unit 75 has a mechanism for depositing the mixture uniformly dispersed in the air by the loosening unit 70 on the mesh belt 76. In addition, you may have a humidity control part in the downstream of the deposition part 75 so that the moisture content of the mixture descend | falling from the loosening part 70 may be adjusted.

  Below the loosening portion 70, an endless mesh belt 76 in which a mesh stretched by a stretch roller 77 (four stretch rollers 77 in the present embodiment) is formed is disposed. The mesh belt 76 moves in one direction by rotating at least one of the stretching rollers 77.

  Further, a suction mechanism 78 as a suction unit that generates an airflow directed vertically downward is provided below the loosening unit 70 via a mesh belt 76. By the suction mechanism 78, the mixture dispersed in the air by the loosening unit 70 can be sucked onto the mesh belt 76. Thereby, the mixture disperse | distributed in the air can be attracted | sucked and the discharge speed from the loosening part 70 can be enlarged. As a result, the productivity of the sheet manufacturing apparatus 120 can be increased. Further, the suction mechanism 78 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.

  Then, by moving the mesh belt 76 and dropping the mixture from the loosening portion 70, it is possible to form a long web W in which the mixture is uniformly deposited. Here, “uniformly deposited” refers to a state where the deposited deposits are deposited with substantially the same thickness and substantially the same density. However, since not all the deposits are manufactured as a sheet, it is sufficient that the portion to be a sheet is uniform. “Non-uniform deposition” refers to a state in which deposition is not uniform.

  The mesh belt 76 may be made of metal, resin, cloth, or non-woven fabric, and may be anything as long as the mixture can be deposited and an air stream can pass through. The hole diameter (diameter) of the mesh belt 76 is, for example, 60 μm or more and 250 μm or less. If the hole diameter of the mesh belt 76 is smaller than 60 μm, it may be difficult to form a stable airflow by the suction mechanism 78. When the hole diameter of the mesh belt 76 is larger than 250 μm, for example, fibers of the mixture may enter between the meshes, and the unevenness of the surface of the manufactured sheet may increase. Further, the suction mechanism 78 can be configured by forming a sealed box having a window of a desired size under the mesh belt 76 and sucking air from other than the window to make the inside of the box have a negative pressure from the outside air.

  As described above, by passing through the loosening part 70 and the depositing part 75 (web forming step), the web W in a soft and swelled state containing a large amount of air is formed. Next, as shown in FIG. 1, the web W formed on the mesh belt 76 is conveyed by the rotational movement of the mesh belt 76. And the web W formed on the mesh belt 76 is conveyed to the pressurization part 60, the heating part 50, the cutting part 90, and the marking part 100 in this example.

1.5.8. Pressurizing unit The sheet manufacturing apparatus 120 of the present embodiment may include a pressing unit 60. In the sheet manufacturing apparatus 120 illustrated in FIG. 1, the pressurizing unit 60 is disposed on the downstream side of the mixing unit 30 and on the upstream side of the heating unit 50. The pressurizing unit 60 is formed into a sheet shape through the loosening unit 70 and the depositing unit 75, and pressurizes the web W without heating. Therefore, the pressurizing unit 60 does not have a heating means such as a heater. That is, the pressurizing unit 60 is configured to perform so-called calendar processing.

  In the pressurizing unit 60, by pressing (compressing) the web W, the distance (distance) between the fibers in the web W is reduced, and the density of the web W is increased. As shown in FIG. 1, the pressurizing unit 60 is configured to sandwich and pressurize the web W with a roller, and includes a pair of pressurizing rollers 61. The pair of pressure rollers 61 have parallel central axes. In addition, the pressurizing unit 60 of the sheet manufacturing apparatus 120 according to the present embodiment includes a first pressurizing unit 60a disposed on the upstream side in the conveyance direction of the web W and a second pressurizing unit 60b disposed on the downstream side thereof. The first pressure unit 60a and the second pressure unit 60b each include a pair of pressure rollers 61. Further, a guide G for assisting the conveyance of the web W is disposed between the first pressure unit 60a and the second pressure unit 60b.

  In the pressurizing unit 60, only the pressurization is performed without being heated, so that the resin in the additive does not melt. Moreover, since only the pressurization is performed in the pressurizing unit 60 without being heated, even if the humidity control unit is provided on the upstream side, the moisture in the mixture is hardly removed here.

  In the sheet manufacturing apparatus 120 of the present embodiment, a pressurizing unit 60 (first pressurizing unit 60a, second pressurizing unit 60b) and a heating unit 50 (first heating unit 50a, second heating unit 50b) are provided. ing. In this example, the heating unit 50 pressurizes the web W, but the pressing force of the pressing unit 60 is preferably set to be larger than the pressing force by the heating unit 50. For example, the pressing force of the pressurizing unit 60 is preferably set to 1 to 3000 kgf, and the pressing force of the heating unit 50 is preferably set to 1 to 200 kgf. Thus, by making the applied pressure of the pressurizing unit 60 larger than that of the heating unit 50, the distance between the fibers contained in the web W can be sufficiently shortened by the pressurizing unit 60, and heating and pressurization is performed in that state. Thus, a thin, high density and high strength sheet can be formed. When reducing the density of the sheet S, the pressing force of the pressing unit 60 can be set to a pressing force smaller than the pressing force when the sheet S using the raw material 1 is manufactured.

  Moreover, in the sheet manufacturing apparatus 120 of this embodiment, as shown in FIG. 1, the diameter of the pressure roller 61 is set to be larger than the diameter of the heating roller 51. Since the pressure roller 61 has a large diameter, it is possible to efficiently convey the web W in a state where it has not been compressed yet. On the other hand, since the web W that has passed through the pressure roller 61 is in a compressed state and is easy to convey, the diameter of the heating roller 51 disposed on the downstream side of the pressure roller 61 may be small. The diameters of the heating roller 51 and the pressure roller 61 are appropriately set according to the thickness and properties of the web W to be manufactured.

  The illustrated pressure unit 60 is an example in which there are two pairs of pressure rollers 61. However, when the pressure unit 60 is used and the pressure roller 61 is used as the pressure unit 60, the pressure unit 60 is pressurized. The number and arrangement of the rollers 61 are not limited, and can be arbitrarily configured as long as the above action can be achieved.

  Furthermore, the member which can contact the web W between the pressure roller 61 of the pressure unit 60 and the heating roller 51 of the heating unit 50 is only the guide G as a web receiving member capable of supporting the web W from below. It is. Therefore, the distance between the pressure roller 61 and the heating roller 51 can be shortened. In addition, since the pressurized web W is quickly heated and pressed, the spring back of the web W is suppressed and a high-strength sheet can be formed.

  By providing the pressure unit 60 (pressure roller 61) and the heating unit 50 (heating roller 51) with the above-described configuration, the sheet is thin, dense and high-strength from a thin and low-density material such as a nonwoven fabric. Can be manufactured.

1.5.9. Heating Unit The sheet manufacturing apparatus 120 of this embodiment includes a heating unit 50. The heating unit 50 is provided on the downstream side of the pressurizing unit 60 described above.

  The heating unit 50 heats the mixture mixed in the mixing unit 30 to bind the plurality of fibers to each other through the additive. Moreover, when moisture is added to the mixture, a state in which hydrogen bonds are formed between the fibers may be formed. The conditioned mixture may be, for example, formed into a web shape. Moreover, the heating unit 50 may have a function of forming the mixture into a predetermined shape.

  In the present specification, “to bind a plurality of fibers through an additive” means that the fiber in the defibrated material is difficult to separate from the additive, and the resin of the additive between the fiber and the fiber. Is arranged, and the fiber and the fiber are in a state in which it is difficult to separate through the additive. The binding is a concept including adhesion, and includes a state in which two or more kinds of objects are difficult to come into contact with each other. Further, when the fibers and the fibers are bound via the composite, the fibers and the fibers may be parallel or intersect, or a plurality of fibers may be bound to one fiber. Further, “fibers are hydrogen bonded” means that a plurality of fibers are bonded (bonded) partially or entirely by hydrogen bonds to each other.

  If the resin that is one of the constituents of the additive is a thermoplastic resin, the resin softens or melts when heated to a temperature above its glass transition temperature (softening point) or melting point, and then Solidify when the temperature drops. The resin softens and comes into contact with the fiber so that the fiber is solidified, and the fiber and the additive can be bound to each other. Further, when other fibers are bound when solidifying, the fibers are bound to each other. The glass transition temperature, melting point, softening point, etc. of the resin are preferably lower than the decomposition temperature and carbonization temperature of the fiber, and it is preferable to select both types in combination so as to have such a relationship.

  On the other hand, when the humidity is adjusted downstream of the deposition unit 75, the heating unit 50 evaporates part or all of the water contained in the mixture. Thereby, the water molecule intervening between the fibers is reduced (removed), whereby hydrogen bonds between the fibers can be formed. Therefore, the heating unit 50 is preferably set to a temperature equal to or higher than the boiling point of water, but may be heated to a temperature equal to or lower than the boiling point of water as long as hydrogen bonding can be performed.

  In addition, in the heating unit 50, pressure may be applied in addition to applying heat to the mixture. In that case, the heating unit 50 converts the mixture into a predetermined shape according to the form of the target sheet S. It will have the function of forming. Although the magnitude | size of the applied pressure is suitably adjusted with the kind of sheet | seat S shape | molded, it can be 3 kPa or more and 1 MPa or less. If the applied pressure is small, a sheet with a high porosity is obtained, and if it is large, a sheet with a low porosity (high density) is obtained.

  Specific examples of the configuration of the heating unit 50 include a heating roller (heater roller), a hot press molding machine, a hot plate, a hot air blower, an infrared heater, and a flash fixing device. In the sheet manufacturing apparatus 120 of the present embodiment illustrated in FIG. 1, the heating unit 50 is configured by a heating roller 51. In the illustrated example, the heating unit 50 heats the web W pressed by a pressing unit 60 (described later). Further, the heating unit 50 may have a function of pressurizing the web W. And by heating the web W, the fibers contained in the web W can be bound together via an additive and a hydrogen bond.

In the illustrated example, the heating unit 50 is configured to sandwich and heat the web W with a roller, and includes a pair of heating rollers 51. As for a pair of heating roller 51, each central axis is parallel. Moreover, the heating part 50 can be comprised not only with a roller etc. but with a flat press part. Although detailed description is omitted here, when a flat press part is used as the heating part 50, it is suitable for a relatively thick sheet, for example, a low density nonwoven fabric. This is suitable for a sheet having a large thickness and taking a long time to transmit heat to the entire web because the flat press portion can take a longer contact time with the web W than using a heating roller. . Note that the pressurizing unit 60 may not be provided on the upstream side of the flat plate-shaped press unit. In this case, since it is not compressed to a high density by the pressurizing unit 60, it is suitable for a relatively low density sheet. The use of a flat press section is more suitable for non-woven fabric than for paper.

  The heating unit 50 includes a first heating unit 50a disposed on the upstream side in the conveyance direction of the web W and a second heating unit 50b disposed on the downstream side thereof, and the first heating unit 50a and the second heating unit 50b. Each part 50b includes a pair of heating rollers 51. Further, a guide G for assisting the conveyance of the web W is disposed between the first heating unit 50a and the second heating unit 50b.

  In addition, a heating material (not shown) such as a halogen heater is provided as a heating means at the center of the cored bar. Each temperature of the heating roller 51 and the heating material is acquired by a temperature detection unit (not shown), and the heating roller 51 and the heating material are controlled based on the acquired temperature by ON-OFF control or electric power control of the heating material. Thereby, the surface temperature of the heating roller 51 can be maintained at a predetermined temperature. Then, by passing the web W between the heating rollers 51, the web W being conveyed can be heated and pressurized. The heating means is not limited to a halogen heater or the like, and for example, a heating means using a non-contact heater or a heating means using hot air may be used.

  In addition, although the heating part 50 shown in figure is an example with two pairs of heating rollers 51, the number and arrangement | positioning of the heating rollers 51 are not limited, It can comprise arbitrarily in the range which can achieve the said effect | action. When the low-density sheet S is formed, the pair of heating rollers 51 can be made into three sets in order to increase the heating time. Further, the configuration of the heating roller 51 of each heating unit 50 (the thickness and material of the release layer, the elastic layer, the core metal, the outer diameter of the roller) and the load that presses the heating roller 51 are different depending on each heating unit 50. Also good.

  As described above, through the heating unit 50 (heating step), the resin contained in the additive is melted and easily entangled with the fibers in the defibrated material, and the fibers are bound. Further, the fibers may be bonded by hydrogen bonding. The mixture of the defibrated material and the additive becomes the sheet S through the heating unit 50.

1.5.10. Cutting unit In the sheet manufacturing apparatus 120 of the present embodiment, the sheet S is arranged on the downstream side of the heating unit 50 in a direction crossing the conveyance direction of the web W (the web W that has passed through the heating unit 50 is the sheet S). The 1st cutting part 90a and the 2nd cutting part 90b as the cutting part 90 which cut | disconnects are arrange | positioned. The cutting part 90 can be provided as needed.

  The first cutting unit 90a includes a cutter, and cuts the continuous sheet S into sheets according to a cutting position set to a predetermined length. Further, a second cutting unit 90b that cuts the sheet S along the conveyance direction of the sheet S is disposed downstream of the first cutting unit 90a in the conveyance direction of the sheet S. The second cutting unit 90b includes a cutter, and cuts (cuts) according to a predetermined cutting position in the conveyance direction of the sheet S. Thereby, a sheet S having a desired size is formed. The cut sheets S are marked one by one in the marking unit 100 and then stacked on the stacker 95 or the like.

1.5.11. Marking Unit In the sheet manufacturing apparatus 120 according to the present embodiment, the marking unit 100 is disposed on the downstream side of the sheet forming unit 40. The marking unit 100 can perform marking on the sheet S to determine the history of the sheet S. When manufacturing the sheet S, the marking unit 100 may perform marking having information corresponding to the number of times the sheet S is recycled to the raw material 1. The marking may be the same number of marks as the number of times of recycling.

  The marking unit 100 can mark the sheets S cut by the cutting unit 90 one by one. The position where marking on the sheet S is performed can be appropriately selected within a range that can be recognized by the acquisition unit 8.

  As long as the marking form on the sheet S can be detected by the acquisition unit 8, a known marking form can be adopted as appropriate. When the acquisition unit 8 is an optical reading device, the marking unit 100 (1) makes fine holes in the sheet S, (2) prints with ink that cannot be read by human eyes, (3 It is possible to employ a method such as embossing that gives a slight unevenness to the sheet S, or bar code printing that can incorporate a large amount of information.

  Further, as described above, the history information of the raw material 1 included in the marking can include the number of times of recycling, the amount of additive, the amount of additional fiber, and the like.

  When the sheet S thus marked is recycled as the raw material 1, the acquisition unit 8 reads the marking to acquire the history, and the control unit 110 adds the additive in the addition unit 32 according to the acquired history. You may control the injection amount. Thus, the history of the raw material 1 such as the number of times of recycling can be grasped by using the marking.

1.5.12. Control Unit The control unit 110 changes the condition of each unit of the sheet manufacturing apparatus 120 based on the history information of the raw material 1 output from the acquisition unit 8. Specifically, when the number of times of recycling by the history information of the raw material 1 is greater than a predetermined number, the control unit 110 switches the switching valve 25 from the first path to the second path, and the first additive An appropriate amount of core-sheath structure resin is charged from the equal charging portion 321, an appropriate amount of flame retardant is charged from the second additive charging portion 32 b, the pressurizing force of the pressurizing portion 60 is reduced, and the conditions of the marking portion 100 are changed. A command can be output to Note that, based on the history information of the raw material 1, the control unit 110 does not immediately switch the switching valve 25, change the additive charging condition, or reduce the pressure applied by the pressurizing unit 60. The raw material 1 that has acquired the history is changed after the time for which the raw material 1 is processed and conveyed until it is changed.

  Further, the control unit 110 may select the type of the raw material 1 to be supplied from the supply unit 9 based on the history information of the raw material 1 acquired from the acquisition unit 8. Specifically, when a plurality of types of raw materials 1 are stored in the supply unit 9, a raw material 1 in a range that can be manufactured with the same or similar amount of additive added is selected and supplied to the crushing unit 10. can do.

  Further, when the control unit 110 changes the condition of the marking unit 100, for example, if the history information of the raw material 1 acquired from the acquisition unit 8 is the number of times of recycling, it corresponds to the number of times obtained by adding 1 to the number of times of recycling. A command can be issued to the marking unit 100 to perform marking.

The control unit 110 includes, for example, a main control unit, a motor drive unit, an operation panel (operation unit), a processing unit, and the like. The display unit displays each condition (for example, the pressure of the pressurizing unit 60) selected by the user. The operation unit is for inputting user operations and the like as data. The operation unit is realized by hardware such as a keyboard and a touch panel, for example. The processing unit performs each process based on operation data, a program, and the like from the operation unit. The processing unit is realized by, for example, hardware such as various processors (CPU, DSP, etc.), ASIC (gate array, etc.), application programs, and OS (eg, general-purpose OS).

1.5.13. Others Although not shown, a cooling unit that cools the sheet S heated by the heating unit 50 may be provided downstream of the heating unit 50. The cooling unit can be configured by a cooling roller or the like, for example. By providing the cooling unit, the resin can be quickly cooled, and the structure of the sheet S can be fixed early. Thereby, for example, it is possible to contribute to an improvement in the throughput and downsizing of the apparatus.

  The sheet manufacturing apparatus 120 of the present embodiment can also have a configuration other than the configuration exemplified above, and can appropriately have a plurality of configurations according to the purpose including the configuration exemplified above. The number and order of the components are not particularly limited, and can be appropriately designed according to the purpose.

  In addition, the sheet manufacturing apparatus 120 of the present embodiment is an apparatus that manufactures the sheet S by a dry method, but is not limited thereto, and may be used in a wet method manufacturing apparatus.

2. Sheet manufacturing method In the sheet manufacturing method of the present embodiment, the raw material 1 containing at least fibers is defibrated, an additive is added to the defibrated material, and a plurality of fibers are bound together via the additive. Thus, the sheet S is manufactured by producing a sheet having a lower density when the raw material is recycled more frequently than when the raw material is recycled less.

  The sheet manufacturing method of this embodiment can be performed using the sheet manufacturing apparatus 120 described above. Since the raw material, defibration, defibrated material, fiber, mixture, additive, resin, fiber, sheet formation and the like are the same as those described in the section of the sheet manufacturing apparatus described above, detailed description is omitted.

  According to such a sheet manufacturing method, a sheet having a function different from that of the raw material can be manufactured when the sheet is recycled a plurality of times. When the sheet is recycled a plurality of times, deterioration of the fiber in the defibrated material is inevitable. However, even if the fiber is deteriorated by recycling a plurality of times as described above, according to such a sheet manufacturing method, it is possible to further recycle into a low-density sheet having a function different from that of the raw material sheet.

3. Other Matters In this specification, the term “homogeneous” means that, in the case of uniform dispersion or mixing, in an object that can define two or more components or two or more components, one component is relative to another component. This means that the existing positions are uniform throughout the system, or the same 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. However, even if it is said that it is uniform, it includes the case where the distances of all the resins are not the same and the concentrations are not completely the same.

  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.

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. For example, although the web W is a single layer in the above embodiment, it may be a multiple layer, or a non-woven fabric or paper created separately may be laminated.

4). Examples Hereinafter, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited at all by the following examples.

  In Example 1 below, a waste ink absorber used for an inkjet printer as a sheet was manufactured using the sheet manufacturing apparatus 120 according to the present invention. FIG. 3 is a table showing additives and the like in the examples.

4.1. Production of first raw material First, the first raw material used in the examples was produced. Here, as shown in FIG. 1 and FIG. 3, used printing paper (printed used paper) of office copy paper manufactured by a wet method as the first raw material was supplied from the supply unit 9. Since used printing paper does not have a history of raw materials, the number of times it is recycled as raw materials is zero. A shredder was used as the crushing unit 10, and the raw material (printed waste paper) supplied from the supply unit 9 was cut into strips of about 6 mm × 14 mm.

  Using a defibrating machine as the defibrating unit 20, the raw material cut in the crushing unit 10 was defibrated. The rotational speed of the defibrating unit 20 (the rotational speed of the rotating unit of the defibrating unit 20) was set to 5000 rpm.

  A cyclone was used as the classification unit 63, and the defibrated material that passed through the defibrating unit 20 was classified.

  A rotary sieve was used as the sorting unit 35, and the classified product that passed through the classifying unit 63 was sorted by the length of the fiber. As the screen of the sorting unit 35, a screen having an opening of 970 μm was used.

  In the mixing unit 30, 15 parts by weight of the resin powder supplied from the first additive input unit 32 a of the addition unit 32 with respect to 100 parts by weight of the defibrated material (fiber) that has passed through the selection unit 35. Mixed. In the mixing unit 30, the defibrated material and the resin were mixed in the air using a turbo fan blower. A screw feeder was used as the first additive input portion 32a. As the resin powder, one having an average particle diameter D50 = 10 μm obtained by integrating titanium oxide with polyester resin was used.

  A rotary sieve was used as the sieving part 70, and the mixture mixed in the mixing part 30 was loosened. As the screen of the sieve unit 70, a screen having an opening of 970 μm was used.

  The suction mechanism 78 of the accumulation unit 75 was operated to move the mesh belt 76, and the defibrated material that passed through the sieve unit 70 was accumulated on the mesh belt 76. Thereafter, the web W deposited on the mesh belt 76 was transferred to the pressure unit 60.

  The web W was pressed with an appropriate pressing force by the pressing roller 61 in the pressing unit 60, and heated to a temperature higher than the temperature at which the additive resin melted by the two heating rollers 51 in the heating unit 50.

  Furthermore, the web W was cut into a size of A4 size at the cutting unit 90. The marking unit 100 marks the information corresponding to one recycling.

  Through the above steps, office copy paper (first raw material), which is a recycled material, was manufactured as the first raw material.

4.2. Production of Second Raw Material As shown in FIG. 3, the same office copy paper (second raw material) was produced using the office copy paper (first raw material) produced in 4.1 above as the raw material. . In this case, the raw material is recycled once. Then, the amount of resin powder added to the defibrated material in the first additive input portion 32a is 10 parts by weight with respect to 100 parts by weight of the defibrated material (fiber), and the number of recycling is equivalent to 2 times. Except that information was marked by the marking unit 100, the manufacturing process of 4.1 was performed.

  In the fiber of the defibrated material classified by the classifying unit 63, a part of the resin added in 4.1 was not completely removed by the defibrating unit 20 and the classifying unit 63, but adhered to the fiber. In No. 1, the amount of the resin powder was 10 parts by weight, which was 5 parts by weight less than 4.1, so that office copy paper having the same function as that produced in 4.1 could be manufactured. .

4.3. 3. Production of Third Raw Material As shown in FIG. 3, office copy paper (third raw material) was also produced using the office copy paper (second raw material) produced in 4.2 above as the raw material. . In this case, the raw material is recycled twice. Then, the amount of the resin powder added to the defibrated material in the first additive loading unit 32a is 10 parts by weight with respect to 95 parts by weight of the defibrated material (fiber), and the second additive charging unit Except for adding 5 parts by weight of fiber from 32b and marking the information corresponding to 3 times of recycling by the marking unit 100, the manufacturing process of 4.1 was performed.

  The same defibrated material as the defibrated material that passed through the sorting unit 35 in 4.1 described above was used as the fiber fed from the second additive etc. charging unit 32b. By adding 5 parts by weight of the fiber from the fiber input part 32b to 95 parts by weight of the defibrated material (fiber), a total of 100 parts by weight of fiber is obtained.

4.4. Example (Manufacture of waste ink absorber)
As shown in FIG. 3, a waste ink absorbing material was manufactured using the office copy paper (third raw material) manufactured in 4.3 above as a raw material.

  First, office copy paper (third raw material) recycled three times as the first raw material was supplied from the supply unit 9. A shredder was used as the crushing unit 10, and the raw material (printed waste paper) supplied from the supply unit 9 was cut into strips of about 6 mm × 14 mm.

  Using a defibrating machine as the defibrating unit 20, the raw material cut in the crushing unit 10 was defibrated. The rotational speed of the defibrating unit 20 (the rotational speed of the rotating unit of the defibrating unit 20) was set to 5000 rpm.

  The switching valve 25 was switched to the second path, and the defibrated material was introduced into the mixing unit 30 without passing through the classification unit 63 and the selection unit 35.

  In the mixing unit 30, 10 parts by weight of the core-sheath structure resin supplied from the first additive input unit 32 a of the addition unit 32 with respect to 100 parts by weight of the defibrated material (fiber) that has passed through the selection unit 35, 5 parts by weight of a flame retardant was mixed from the second additive charging portion 32b. In the mixing unit 30, a defibrated material, a resin, and a flame retardant were mixed in the air using a turbofan blower. As the core-sheath resin, a core resin is a polyester resin and a sheath part is polyethylene, and a 1.7 dtex fibrous resin (Tetron Co., Ltd. Tetron. The sheath part melts at a temperature of 100 ° C. or more). . As the flame retardant, aluminum hydroxide (B53 manufactured by Nippon Light Metal Co., Ltd.) was used.

A rotary sieve was used as the sieving part 70, and the mixture mixed in the mixing part 30 was loosened. As the screen 70, a screen having a mesh size of 3000 μm was used.

  The suction mechanism 78 of the accumulation unit 75 was operated to move the mesh belt 76, and the defibrated material that passed through the sieve unit 70 was accumulated on the mesh belt 76. Thereafter, the web W deposited on the mesh belt 76 was transferred to the pressure unit 60.

  The web W is pressed by the pressing unit 60 with a pressing force smaller than that during the production of the first to third raw materials by the pressing roller 61, and the heating unit 50 uses the three heating rollers 51 at 220 ° C. to add the additives. The resin was heated to a temperature higher than the melting temperature. The waste ink absorbing material is recycled four times as a sheet. However, since the waste ink absorbing material absorbs a large amount of waste ink and is difficult to recycle thereafter, it cannot be read even if marking is performed.

  Further, the web W was cut at the cutting unit 90 to obtain a waste ink absorbing material.

  According to the embodiment, it is possible to manufacture a waste ink absorbing material having a density lower than that of the office copy paper used as the raw material of the above 4.1 to 4.3 only by changing the conditions and additives of the apparatus. I was able to.

  Since a part of the resin added in the steps 4.1 to 4.3 was attached to the fiber of the defibrated material of the raw material 1 of the example, even if the amount of the resin is reduced in the example, A waste ink absorber having sufficient strength could be produced.

DESCRIPTION OF SYMBOLS 1 ... Raw material, 8 ... Acquisition part, 9 ... Supply part, 10 ... Crushing part, 11 ... Crushing blade, 15 ... Hopper, 20 ... Defibration part, 21 ... Inlet port, 22 ... Discharge port, 25 ... Switching valve, 30 ... Mixing unit, 31 ... Supply port, 32 ... Adding unit, 32a ... First addition Material input unit, 32b ... Second additive input unit, 35 ... Selection unit, 36 ... Introduction port, 37 ... Discharge port, 38 ... Hopper, 40 ... Sheet Formation part, 50 ... heating part, 50a ... first heating part, 50b ... second heating part, 51 ... heating roller, 60 ... pressurizing part, 60a ... first addition Pressure part, 60b ... 2nd pressurization part, 61 ... Pressure roller, 63 ... Classification part, 64 ... Introduction port, 65 ... Cylindrical part, 66 ... Reverse cone part, 67 ... Lower discharge 68 ... Upper discharge port, 69 ... Receiving part, 70 ... Relief part, 71 ... Introduction port, 75 ... Deposition part, 76 ... Mesh belt, 77 ... Stretching Roller, 78 ... Suction mechanism, 81, 82, 83, 84, 85, 86 ... Pipe, 90 ... Cutting part, 90a ... First cutting part, 90b ... Second cutting part, 95 ... Stacker, 100 ... Marking unit, 110 ... Control unit, 120 ... Sheet manufacturing device, G ... Guide, W ... Web, S ... Sheet

Claims (5)

A defibrating unit for defibrating at least raw materials containing fibers;
An additive part for adding an additive to the defibrated material defibrated in the defibrating part,
A sheet forming unit that forms a sheet by binding a plurality of the fibers together via the additive,
A sheet manufacturing apparatus that manufactures a sheet having a lower density when the raw material is recycled more frequently than when the raw material is recycled less.   2. The sheet manufacturing apparatus according to claim 1, wherein a resin having a core-sheath structure is added as the additive when the number of times of recycling is larger. A pressurizing unit that pressurizes when forming the sheet;
3. The sheet manufacturing apparatus according to claim 1, wherein a pressing force when the number of times of recycling is smaller is larger than a pressing force when the number of times of recycling is large. A marking part that performs marking indicating the number of times the raw material is recycled when manufacturing a sheet;
An acquisition unit for reading the marking and acquiring the number of times of recycling;
A control unit for controlling whether to manufacture a sheet having a high density or a sheet having a low density according to the acquired number of times of recycling; and
The sheet manufacturing apparatus according to claim 1, further comprising: Defibrating raw materials containing at least fibers,
Add additives to the defibrated defibrated material,
A method for producing a sheet by binding a plurality of fibers through the additive,
A sheet manufacturing method characterized in that a sheet having a lower density is manufactured when the raw material is recycled more frequently than when the raw material is recycled less.

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