Narrowing device

Abstract

To provide a narrowing device capable of narrowing the width of a sheet.SOLUTION: A narrowing device has at least one conveying section and at least one narrowing section, which narrows the width of a sheet while unwinding the sheet, wherein the sheet contains cellulose-based fibers and resin components, at least one of the conveying sections is a pair of nip rolls, and the pair of nip rolls are arranged so that the angle between the direction of the width of the sheet introduced into the pair of nip rolls and the direction of the axis of rotation of the pair of nip rolls is 10° or more.SELECTED DRAWING: Figure 16

Description

Technical Field

[0001] The present invention relates to a narrowing device.

Background Art

[0002] A method of manufacturing a sheet-like material using a belt dryer, a drum dryer, or the like is known. The manufactured sheet may be further subjected to subsequent processes such as crushing.

[0003] Patent Document 1 discloses an apparatus in which a cutting device for cutting a strand group is provided downstream of a narrowing device that narrows the width of the strand group while guiding the strand group. Further, Patent Document 2 discloses a waste film processing apparatus that divides a wide plastic film with a cutting blade, narrows the width of each divided film, and feeds it into a crusher to obtain a waste film.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] If the inlet of a crusher or the like used in the process after manufacturing the sheet is smaller than the sheet width, the sheet may stay at the inlet. In order to prevent the sheet from staying, it is necessary to use a device in which the inlet is sufficiently larger than the sheet width, resulting in an increase in manufacturing cost. The inventor has considered changing the sheet width to an appropriate size according to the inlet and the like, and has reached the present invention. That is, an object of the present invention is to provide a narrowing device capable of narrowing the width of a sheet.

Means for Solving the Problems

[0006] As a result of intensive studies by the present inventors, it has been found that the above problems can be solved by a narrowing device having a conveying unit and a narrowing unit. That is, the present invention includes the following.

[0007] [1] A narrowing device that has at least one conveying unit and at least one narrowing unit and narrows the width of a sheet while feeding out the sheet, wherein the sheet contains a cellulose-based fiber and a resin component, at least one of the conveying units is a pair of nip rolls, and the pair of nip rolls is arranged such that the angle formed by the width direction of the sheet introduced into the pair of nip rolls and the rotation axis direction of the pair of nip rolls is 10° or more. [2] The narrowing device according to [1], wherein the sheet contains a cellulose-based fiber and a rubber component. [3] The narrowing device according to [1] or [2], wherein at least one of the conveying units is provided on the downstream side in the feeding direction with respect to the narrowing unit. [4] The narrowing device according to any one of [1] to [3], wherein at least one of the narrowing units has an inlet and an outlet for the sheet, and the width of the outlet is smaller than the width of the sheet. [5] The narrowing device according to [4], wherein the inlet and the outlet are connected by a wall portion. [6] The narrowing device according to any one of [1] to [5], wherein at least one of the narrowing units is at least a pair of driving or non-driving rolls, and the rolls forming a pair are arranged to be separated from each other with a predetermined distance in the width direction of the sheet. [7] The narrowing device according to any one of [1] to [6], wherein at least one of the narrowing units is a pair of belt conveyors, and the distance between the pair of belt conveyors is arranged to decrease toward the downstream in the feeding direction. [8] The narrowing device according to any one of [1] to [7], wherein at least one of the narrowing portions is an annular wire, a multi-stage roll arranged in a spiral shape, or an air gripper. [9] The narrowing device according to any one of [1] to [8], wherein a narrowing assist portion is provided in the narrowing portion.

[10] The narrowing assist portion is an air discharge portion, wherein at least one of the narrowing portions has an inlet and an outlet of the sheet, The narrowing device according to [9], wherein the inlet and the outlet of the narrowing portion are connected by a wall portion.

[11] The narrowing device according to [9], wherein at least one of the narrowing portions has an inlet and an outlet of the sheet, and the narrowing assist portion is a driving or non-driving roll or a belt conveyor provided between the inlet and the outlet.

[12] The narrowing device according to any one of [1] to

[11] , further comprising an introduction portion provided upstream in the feeding direction with respect to the narrowing portion, for introducing the sheet to the downstream side.

[13] The narrowing device according to

[12] , wherein the introduction portion is a belt conveyor, a belt dryer, a drum dryer, or an unwinder.

[14] A method for manufacturing a sheet, comprising a narrowing step of narrowing a sheet containing a cellulose-based fiber and a resin component, using the narrowing device according to any one of [1] to

[13] . [Advantages of the Invention]

[0008] According to the present invention, it is possible to provide a narrowing device capable of narrowing the width of a sheet. Thereby, the device used in the subsequent process can be miniaturized, and the manufacturing cost can be reduced. [Brief Description of the Drawings]

[0009]

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Figure 17

Mode for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described in detail. However, the description of the constituent elements described below is an example (representative example) of an embodiment of the present invention, and the present invention is not limited to these contents, and can be variously modified and implemented within the scope of the gist. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as the lower limit value and the upper limit value.

[0011] One embodiment of the present invention is a narrowing device that has at least one conveying unit and at least one width narrowing unit, and narrows the width of the sheet while feeding out the sheet. According to the narrowing device of the present embodiment, the width of the sheet discharged from the downstream in the feeding direction can be made smaller than that before being introduced from the upstream in the feeding direction. In this specification, the width of the sheet discharged from the downstream in the feeding direction refers to the length in the major axis direction of a cross-section perpendicular to the feeding direction. Also, the thickness of the sheet discharged from the downstream in the feeding direction refers to the length in the minor axis direction of a cross-section perpendicular to the feeding direction. Also, according to the degree of narrowing of the sheet, the thickness of the sheet increases. Thereby, when the subsequent process is a crushing process, a cutting process, etc., compared with the case where it is not narrowed, crushing, cutting, etc. of the sheet become easier.

[0012] The feeding direction of the sheet is not particularly limited, but it is preferable that the main feeding direction is 0° or more and less than 90° from vertically downward. The main feeding direction can be, for example, the direction from the location where the sheet is introduced into the narrowing device to the location where the sheet is discharged from the narrowing device. By setting such an angle, it can be conveyed according to gravity. On the other hand, in a part of the narrowing device according to the present embodiment, it does not prevent the feeding direction from being 90° or more from vertically downward.

[0013] The width direction of the sheet is not particularly limited, but it is preferable that it is horizontal from the time it is introduced into the narrowing device until it is discharged. By setting the width direction of the sheet to be horizontal, unintended deformation of the sheet can be suppressed. On the other hand, in a part of the narrowing device according to the present embodiment, the width direction of the sheet does not have to be horizontal.

[0014] The material of the sheet introduced into the narrowing device of the present embodiment is not particularly limited, but it is preferably contained cellulose-based fibers and a resin component. The sheet containing cellulose-based fibers and a resin component may have strong tackiness and is likely to stay in the narrowing portion or the like. However, according to the narrowing device of the present embodiment, the width of the sheet can be narrowed without staying.

[0015] Cellulose-based fibers refer to fibrous cellulose or its modified products, as well as those obtained by defibrating and beating these. Examples of fibrous cellulose include microfibrillated cellulose. The microfibrillated cellulose is not particularly limited, and known ones can be used. The maximum value of the fiber width of the microfibrillated cellulose is preferably 1000 nm or less, more preferably 100 nm or less, further preferably 50 nm or less, still more preferably 20 nm or less, and particularly preferably 10 nm or less.

[0016] The number average fiber width of the microfibrillated cellulose is, for example, 1000 nm or less. The number average fiber width of the microfibrillated cellulose is preferably, for example, 2 nm or more and 1000 nm or less, more preferably 2 nm or more and 100 nm or less, further preferably 2 nm or more and 50 nm or less, and particularly preferably 2 nm or more and 10 nm or less. Incidentally, the microfibrillated cellulose is, for example, single-fiber cellulose.

[0017] The fiber width of microfibrillar cellulose is measured as follows using, for example, an electron microscope. First, an aqueous suspension of microfibrillar cellulose with a concentration of 0.05% by mass or more and 0.1% by mass or less is prepared, and this suspension is cast onto a carbon film-coated grid that has been hydrophilized to obtain a sample for TEM observation. When fibers with a wide width are included, the SEM image of the surface cast on glass may be observed. Next, observation is performed on the electron microscope image at any one of magnifications of 1000 times, 5000 times, 10000 times, or 50000 times according to the width of the fiber to be observed. However, the sample, observation conditions, and magnification are adjusted so as to satisfy the following conditions.

[0018] (1) Draw a straight line X at an arbitrary position within the observation image, and more than 20 fibers intersect the straight line X. (2) Draw a straight line Y that intersects the straight line perpendicularly within the same image, and more than 20 fibers intersect the straight line Y.

[0019] For the observation image that satisfies the above conditions, visually read the widths of the fibers that intersect the straight line X and the straight line Y. In this way, obtain three or more sets of observation images of surface portions that do not overlap with each other at least. Next, for each image, read the widths of the fibers that intersect the straight line X and the straight line Y. As a result, at least 20 × 2 × 3 = 120 fiber widths are read. The largest of these fiber widths is taken as the maximum value of the fiber width. And the average value of the read fiber widths is taken as the number-average fiber width of the microfibrillar cellulose.

[0020] The fiber length of the microfibrillar cellulose is not particularly limited, but is preferably, for example, 0.1 μm or more and 1000 μm or less, more preferably 0.1 μm or more and 800 μm or less, and even more preferably 0.1 μm or more and 600 μm or less. By setting the fiber length within the above range, destruction of the crystalline regions of the microfibrillar cellulose can be suppressed. Incidentally, the fiber length of the microfibrillar cellulose can be determined, for example, by image analysis using TEM, SEM, or AFM.

[0021] The microfibrillar cellulose preferably has a type I crystal structure. Here, the fact that the microfibrillar cellulose has a type I crystal structure can be identified from the diffraction profile obtained from a wide-angle X-ray diffraction photograph using monochromatized CuKα (λ = 1.5418 Å) with graphite. Specifically, it can be identified because it has typical peaks at two positions near 2θ = 14° or more and 17° or less and near 2θ = 22° or more and 23° or less. The proportion of the type I crystal structure in the microfibrillar cellulose is preferably, for example, 30% or more, more preferably 40% or more, and even more preferably 50% or more. Regarding the crystallinity, the X-ray diffraction profile is measured and determined by a conventional method from the pattern (Seagal et al., Textile Research Journal, Vol. 29, p. 786, 1959).

[0022] The axial ratio (fiber length / fiber width) of the microfibrillar cellulose is not particularly limited, but is preferably, for example, 50 or more and 10,000 or less, and more preferably 100 or more and 1,000 or less. By setting the axial ratio to the above lower limit or more, it becomes easier to form a composite material containing the microfibrillar cellulose. By setting the axial ratio to the above upper limit or less, it is preferable in terms of facilitating handling such as dilution when, for example, treating the microfibrillar cellulose as a dispersion liquid.

[0023] The microfibrillar cellulose in the present embodiment has, for example, both a crystalline region and an amorphous region.

[0024] Examples of modification include oxidation, etherification, esterification, silane coupling, fluorination, cationization, etc. Esterification refers to a condensation reaction between an oxo acid of an organic acid or an inorganic acid and the hydroxy group of cellulose . Specifically, it is a reaction that produces carboxylic acid esters, thioesters, phosphate esters, sulfate esters, nitrate esters, carbonate esters, etc.

[0025] For fibrillation or beating, for example, a wet atomizer, a high-speed fibrillator, a grinder (mortar mill), a high-pressure homogenizer or an ultra-high-pressure homogenizer, a high-pressure impact crusher, a ball mill, a bead mill, a disk refiner, a conical refiner, a twin-screw kneader, a vibration mill, a homomixer under high-speed rotation, an ultrasonic disperser, or a beater can be used.

[0026] Examples of the resin component include a rubber component, a thermoplastic resin, and a thermosetting resin. Examples of the rubber component include natural rubber, modified natural rubber, deproteinized natural rubber, and synthetic rubber. Examples of the modified natural rubber include epoxidized natural rubber, hydrogenated natural rubber, chlorinated natural rubber, chlorosulfonated natural rubber, and grafted natural rubber of methyl methacrylate or styrene monomer.

[0027] Examples of the synthetic rubber include, for example, styrene-butadiene rubber (SBR), nitrile rubber (NBR), chloroprene rubber (CR), ethylene-propylene rubber (EPDM), butyl rubber (IIR), chlorobutyl rubber (CIIR), acrylic rubber (ACM), silicone rubber (Q), fluororubber (FKM), butadiene rubber (BR), epoxidized butadiene rubber (EBR), epichlorohydrin rubber (CO, CEO), urethane rubber (U), polysulfide rubber (T), etc. Examples of the nitrile rubber include modified nitrile rubbers such as hydrogenated nitrile rubber (H-NBR), carboxyl group-modified nitrile rubber, silicone-modified nitrile rubber, maleic acid-modified nitrile rubber, hydroxyl group-modified nitrile rubber, etc., or those obtained by hydrogenating these, and acrylonitrile-butadiene-isoprene copolymers in which a part of butadiene is replaced by isoprene. Hydrogenated nitrile rubber may be called hydrogenated nitrile rubber or hydrogenated acrylonitrile-butadiene rubber, etc. Hydrogenated nitrile rubber can be obtained by hydrogenating the double bonds contained in nitrile rubber. These rubber components may be used alone or in combination of two or more. Further, these rubber components may be raw materials before crosslinking having no crosslinked structure or those having a crosslinked structure.

[0028] Examples of the thermoplastic resin include polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, ethylene-vinyl acetate copolymer, poly(alkyl (meth)acrylate) polymer, copolymer of alkyl (meth)acrylate, polyester, polycarbonate, polyamide, polyacetal, polyphenylene oxide, and the like.

[0029] Examples of the thermosetting resin include polyurethane, epoxy resin, oxetane resin, phenol resin, urea resin, melamine resin, unsaturated polyester resin, silicone resin, and diallyl phthalate resin.

[0030] Among the above resin components, a rubber component is preferable, and natural rubber, modified natural rubber, deproteinized natural rubber, and diene-based synthetic rubber are preferable, and natural rubber is more preferable.

[0031] The adhesion of the sheet introduced into the narrowing device is not particularly limited, and examples thereof include 1 gf or more, 5 gf or more, 10 gf or more, or 20 gf or more. The upper limit of the adhesion is not limited, and examples thereof include 1000 gf or less, 500 gf or less, 300 gf or less, 100 gf or less, and 30 gf or less. According to the narrowing device of the present embodiment, it is possible to narrow the sheet having such adhesion. The adhesion can be measured, for example, using a probe tack tester TAC1000 (manufactured by Resca Co., Ltd.). Specifically, the temperature of the probe and the stage is set to 25° C., and measurement can be performed using a probe having a diameter of 5 mm. The sheet to be measured can be cut into a size of 50 mm × 50 mm and then measured.

[0032] The thickness of the sheet introduced into the narrowing device is not particularly limited, but is usually 0.001 mm to 0.5 mm, preferably 0.005 mm to 0.1 mm, and more preferably 0.01 mm to 0.05 mm. When the thickness of the sheet is within the above range, there are great advantages that the crushing, cutting, etc. of the sheet are facilitated when using the narrowing device of the present embodiment.

[0033] The thickness of the sheet discharged from the narrowing device is not particularly limited, but is usually 0.002 mm to 4 mm, preferably 0.01 mm to 0.8 mm, and more preferably 0.02 mm to 0.4 mm.

[0034] The width of the sheet introduced into the narrowing device is not particularly limited, but is usually 0.1 m to 5 m, preferably 0.3 m to 4 m, and more preferably 0.5 m to 3 m.

[0035] The width of the sheet discharged from the narrowing device is not particularly limited, but is usually 0.013 m to 2. 5 m, preferably 0.038 m to 2 m, and more preferably 0.063 m to 1.5 m.

[0036] The manufacturing method of the sheet is not particularly limited, and known methods can be used. For example, it can be manufactured by adding a resin component to a dispersion of cellulose-based fibers, mixing them, and then heating and drying. In the heating and drying process of the mixed solution, known heating and drying devices can be used. For example, hot air drying devices, stirring drying devices, rotary drying devices, disk drying devices, roll-type heating devices, plate-type heating devices, fluidized bed drying devices, band-type drying devices (also called belt dryers), filtration drying devices, vibration fluidized drying devices, airflow drying devices, vacuum drying devices, infrared heating devices, far-infrared heating devices, microwave heating devices, high-frequency drying devices, drum dryers, etc. can be used. When the narrowing device of the present embodiment has an introduction part described later, the heating and drying process may be performed in the introduction part.

[0037] When adding a resin component to a dispersion of cellulose fibers, the lower limit of the solid content of the cellulose fibers with respect to 100 parts by mass of the resin component solid content is preferably 1 part by mass or more, more preferably 5 parts by mass or more. Also, the upper limit of the solid content of the cellulose fibers with respect to 100 parts by mass of the resin component solid content is preferably 500 parts by mass or less, more preferably 50 parts by mass or less. That is, the solid content of the cellulose fibers with respect to 100 parts by mass of the resin component solid content may be, for example, 5 to 500 parts by mass, may be 10 to 50 parts by mass, or may be 15 to 25 parts by mass.

[0038] The solid content concentration can be calculated by the following formula from the mass of the obtained dried product and the mass of the liquid subjected to drying, after drying a measurement target such as a predetermined amount of dispersion liquid in a dryer at 105 °C until it reaches a constant weight. Solid content concentration of the liquid subjected to drying [%] = mass of dried product [g] / mass of liquid subjected to drying [g] × 100

[0039] The sheet produced at the mixing ratio within the above range may have high tackiness, but if the narrowing device of the present embodiment is used, the width of the sheet can be narrowed without staying.

[0040] [Conveying section] The narrowing device of the present embodiment has at least one conveying section. The conveying section is for continuously feeding out the sheet introduced into the narrowing device. It is preferable that at least one of the conveying sections is a pair of rolls, a single-side roll, a suction section, an air discharge section, or a pair of conveyors. When the narrowing device of the present embodiment has two or more conveying sections, one of these types may be included in plurality, or a plurality of these types may be included. The pair of rolls is preferably a pair of nip rolls. When a pair of nip rolls is used, the adhesiveness of the sheet is reduced by being pressurized by the nip rolls, and it is possible to suppress the sheet from staying at the inlet or inside of the device used in the subsequent process such as the crushing process.

[0041] An example of a pair of nip rolls is shown in FIG. 1. The sheet 1 is fed in the direction of the arrow while being sandwiched between a pair of nip rolls 2.

[0042] The distance between the pair of nip rolls at the position where the sheet contacts the pair of nip rolls is preferably 1.5 or less, more preferably 1 or less, and particularly preferably 0.8 or less with respect to the thickness of the sheet.

[0043] When at least one of the conveying units is a pair of nip rolls, the pair of nip rolls is preferably arranged such that the angle formed by the width direction of the sheet introduced into the pair of nip rolls and the rotation axis direction of the pair of nip rolls is 10° or more. The angle formed by the width direction of the sheet and the rotation axis direction of the pair of nip rolls is more preferably 30° or more. The upper limit of the angle formed by the width direction of the sheet and the rotation axis direction of the pair of nip rolls is not particularly limited, but can be 90° (that is, perpendicular) or less. When the sheet contains a cellulosic fiber and a resin component, the sheet tends to have high tackiness. By introducing such a highly tacky sheet obliquely to the pair of nip rolls, pressure is also applied in the width direction of the sheet, and the sheet is narrowed while being conveyed. In the present specification, the width direction of the sheet introduced into the conveying unit refers to the major axis direction of the cross-section perpendicular to the feeding direction of the sheet.

[0044] The single-sided roll is composed of a driving roll and a wall, and the sheet passes between the roll and the wall as the roll is driven. An example of a single-sided roll is shown in FIG. 2. The sheet 1 is fed in the direction of the arrow while being sandwiched between the driving roll 3 and the wall 31.

[0045] As another example of the single-sided roll, there is one composed of a non-driving roll and a belt conveyor. The sheet is fed in the conveying direction while being sandwiched between the non-driving roll and the belt conveyor.

[0046] The length of the rotating shaft of the driving roll or the non-driving roll used for the single-side roll is preferably greater than the width direction of the sheet. On the other hand, the length of the rotating shaft of the driving roll or the non-driving roll may be smaller than the width direction of the sheet. When the length of the rotating shaft of the driving roll or the non-driving roll is smaller than the width direction of the sheet, a plurality of driving rolls or non-driving rolls may be arranged in the rotating shaft direction.

[0047] When a pair of rolls or a single-side roll is used as the conveying unit, the thickness of the sheet passing through the conveying unit can be made sufficiently small. Here, the thickness of the sheet passing through the conveying unit refers to the length in the minor axis direction of the cross-section perpendicular to the feeding direction.

[0048] When the conveying unit is a pair of rolls or a single-side roll, it is preferable that their rotating shafts are arranged parallel or perpendicular to the width direction of the sheet introduced into the conveying unit.

[0049] The suction unit sucks the sheet from the downstream side in the feeding direction of the sheet and has at least a suction port and a discharge port. The suction unit can adopt a known configuration. The shapes of the suction port and the discharge port are not particularly limited and may be polygonal, elliptical, circular, etc. Examples of the polygon include a triangle, a quadrilateral, a pentagon, a hexagon, an octagon, a dodecagon, etc. The width of the suction port and the discharge port refers to the maximum width of the region through which the sheet passes. The maximum width of the discharge port is preferably smaller than the width of the sheet introduced into the conveying unit.

[0050] An example of the suction unit is shown in FIG. 3. The sheet 1 is sucked from the suction port 41 of the suction unit 4 and discharged from the discharge port 42.

[0051] The air discharge unit blows air to the downstream side in the feeding direction of the sheet to send out the sheet. The air discharge unit can adopt a known configuration. In a preferred embodiment, the air discharge part has a plurality of air discharge ports. From the viewpoint of uniformly applying air to the sheet, it is preferable that the plurality of air discharge parts are arranged in the width direction of the sheet.

[0052] An example of the air discharge part is shown in FIG. 4. The air discharge part 5 shown in FIG. 4 has a plurality of air discharge ports 51 arranged in the width direction of the sheet. In FIG. 4, the air blowing direction is represented by a dotted arrow. The sheet 1 is fed out by the air discharged from the air discharge port 51.

[0053] As an example, the pair of conveyors are arranged to face each other with a predetermined distance therebetween. Each conveyor is driven toward the downstream side in the feeding direction. The conveyor may be a roller conveyor or a belt conveyor. The belt conveyor has a head pulley, a tail pulley, and a conveyor belt, and can convey the sheet in contact with the conveyor belt from the head pulley toward the tail pulley. The distance between the pair of conveyors is not particularly limited, but examples of the distance at the closest part can include 0.5 mm to 1000 mm. An example in the case where the pair of conveyors are belt conveyors arranged to face each other with a predetermined distance therebetween is shown in FIG. 5. The sheet 1 is fed out between the pair of belt conveyors 6 in the direction of the arrow.

[0054] As another example, the pair of conveyors are a first and a second belt conveyor. The first and second belt conveyors each convey the sheet, and the tail pulley of the first belt conveyor is close to or in contact with the conveyor belt of the second belt conveyor via the conveyor belt. At the proximity or contact location, the sheet is sandwiched and conveyed. With this configuration, the conveying direction can be changed without causing the sheet to stay. Also, it is preferable to arrange the second belt conveyor to convey the sheet in a substantially vertical direction. When the inlet of the machine used in subsequent processes such as the crushing process and the cutting process is provided on the upper surface, arranging it in this way makes it easier to guide the sheet to the inlet. An example where the pair of conveyors are the first and second belt conveyors is shown in FIG. 6.

[0055] [Narrowing section] The narrowing device of the present embodiment has at least one narrowing section. The narrowing section guides the sheet downstream in the feeding direction while narrowing the width of the sheet. The narrowing section may be capable of continuously feeding out the sheet introduced into the narrowing device. In this case, the narrowing section also functions as a conveying section, and the narrowing device of the present embodiment may or may not have a conveying section other than the narrowing section.

[0056] Examples of the narrowing section include those having an inlet of the sheet and an outlet, and the width of the outlet is smaller than the width of the sheet. The width of the inlet is not particularly limited, but is preferably larger than the width of the sheet. It is preferable that the inlet and the outlet are connected by a wall portion. On the other hand, the inlet and the outlet may be constituted by different members. The shapes of the inlet and the outlet are not particularly limited, and may be polygonal, elliptical, circular, or the like. Examples of the polygon include a triangle, a quadrilateral, a pentagon, a hexagon, an octagon, a dodecagon, and the like. The widths of the inlet and the outlet refer to the maximum width of the region through which the sheet passes. As an example of the narrowing section, FIG. 7 shows a trapezoidal box 7 having an inlet 71, an outlet 72, and a wall portion 73. In FIG. 7, the inlet 71 and the outlet 72 are square. The width of the inlet 71 is larger than the width of the sheet 1, and the width of the outlet 72 is smaller than the width of the sheet 1. FIG. 8 shows an example in which the trapezoidal boxes 7 are arranged in series. As an example of the narrowing section, FIG. 9 shows a hopper 7' having an inlet 71', an outlet 72', and a wall portion 73'. In FIG. 9, the inlet 71' and the outlet 72' are circular. The width of the inlet 71' is larger than the width of the sheet 1, and the width of the outlet 72' is smaller than the width of the sheet 1.

[0057] As another example of the narrowing portion, there is at least a pair of driving or non-driving rolls, and the paired rolls are arranged to be separated from each other with a predetermined distance in the width direction of the sheet. As the predetermined distance, 1.5 or less is preferable with respect to the width of the sheet, 1.0 or less is more preferable, and 0.8 or less is particularly preferable. When using a pair of driving or non-driving rolls, there is little possibility that the sheet stays due to the friction between the narrowing portion and the sheet. There may be a plurality of the above rolls, and it is preferable that the distance between at least a pair of rolls is 1.5 or less with respect to the width of the sheet, more preferably 1.0 or less, and particularly preferably 0.8 or less. Fig. 10 shows an example of a narrowing portion having a plurality of pairs of rolls 8. In Fig. 10, the distance between the pair of rolls at the lowermost stage on the drawing surface is smaller than the width of the sheet, but the narrowing portion that the narrowing device of the present embodiment can have is not limited to this, and the distance between the pair of rolls at the lowermost stage is larger than the width of the sheet, and the aspect where the distance between the other pair of rolls is smaller than the width of the sheet is also included. Each roll may be a driving roll or a non-driving roll.

[0058] As another example of the narrowing portion, there is at least a pair of belt conveyors, and the distance between the pair of belt conveyors is arranged to become smaller as it goes downstream in the feeding direction. The pair of belt conveyors drives the sheet to be fed downstream in the feeding direction. When using a belt conveyor, there is little possibility that the sheet stays due to the friction between the narrowing portion and the sheet. Fig. 11 shows a pair of belt conveyors 9 as an example.

[0059] As another example of the narrowing portion, there are an annular wire, a multi-stage roll arranged in a spiral shape, or an air gripper.

[0060] The shape of the annular wire is not particularly limited as long as it is annular, but a polygon, an ellipse, or a circle is preferred. Examples of the polygon include a triangle, a quadrilateral, a pentagon, a hexagon, an octagon, a dodecagon, etc. The width of the annular wire is preferably narrower than the width of the sheet. Here, the width of the annular wire refers to the maximum width of the region through which the sheet passes. When using an annular wire, since the contact area between the narrowed portion and the sheet is small, there is little risk of the sheet staying due to the friction between the narrowed portion and the sheet. As an example, FIG. 12 shows a plurality of annular wires 10 arranged. In FIG. 12, the widths of the plurality of annular wires 10 decrease from the upstream to the downstream in the feeding direction. The annular wire 10 may each be regarded as one narrowed portion, but if the most upstream annular wire 10 is regarded as the inlet and the most downstream annular wire 10 is regarded as the outlet, the entire plurality of annular wires 10 can also be regarded as one narrowed portion having an inlet and an outlet for the sheet, and the width of the outlet is smaller than the width of the sheet.

[0061] The spiral multi-stage roll is composed of at least two pairs of driving or non-driving rolls, and preferably composed of at least two pairs of driving rolls. The rotation axes of each pair are arranged in parallel. Also, the rolls forming a pair are preferably arranged at a distance of 1 to 10 times the thickness of the sheet. The rotation axes of each pair are arranged in a plane substantially parallel to the plane including the rotation axes of the adjacent pair and are arranged at a predetermined angle with the rotation axes of the adjacent pair. That is, they are arranged in a so-called twisted position. The above-mentioned predetermined angle is not particularly limited, is more than 0° and less than 180°, preferably 10° or more and 170° or less, and more preferably 30° or more and 150° or less. When using a spiral multi-stage roll as the narrowed portion, the width of the sheet can be narrowed each time it passes through a pair of rolls. Specifically, when the sheet contains cellulose-based fibers and a resin component, the sheet tends to have high tackiness. By introducing such a highly tacky sheet obliquely to a pair of rolls, pressure is also applied in the width direction of the sheet, and the sheet is narrowed. As an example, FIG. 13 shows a spiral multi-stage roll 11 arranged.

[0062] An air gripper refers to a mechanism that sends air into the grip part to increase the volume of the grip part, thereby holding the object clamped by the grip part with an appropriate force. In this embodiment, a cylindrical air gripper is preferred. When air is sent into the grip part, the inner diameter of the grip part becomes smaller, so the width of the sheet introduced into the air gripper can be reduced. As an example, the air gripper 12 is shown in FIG. 14.

[0063] When the narrowing device of this embodiment has two or more narrowing parts, one or more of these types may be included, or a plurality of these types may be included.

[0064] The order of the conveying part and the narrowing part is not particularly limited, and it may be an aspect in which at least one of the conveying parts is provided on the downstream side in the feeding direction with respect to the narrowing part. Also, it may be an aspect in which at least one of the conveying parts is provided on the upstream side in the feeding direction with respect to the narrowing part. That is, when the narrowing device of this embodiment has a plurality of conveying parts, conveying parts may be provided before and after the narrowing part. Also, a plurality of conveying parts may be provided continuously. Similarly, when the narrowing device of this embodiment has a plurality of narrowing parts, narrowing parts may be provided before and after the conveying part. Also, a plurality of narrowing parts may be provided continuously.

[0065] Also, the conveying part and the narrowing part may be provided integrally. For example, an aspect in which a pair of rolls as the conveying part are provided inside a trapezoidal box as the narrowing part can be mentioned.

[0066] [Narrowing Auxiliary Part] In the narrowing device of this embodiment, a narrowing auxiliary part may be provided on the narrowing part. By having the narrowing auxiliary part, it is possible to prevent the sheet from staying in the narrowing part.

[0067] As an example of the narrowing assistance part, an air discharge part can be mentioned. The air discharge part as the narrowing assistance part only needs to be able to prevent the sheet from staying in the narrowing part, and it is not necessary to be able to send the sheet to the downstream side in the feeding direction. That is, the air discharge part as the narrowing assistance part can blow air to the downstream side in the feeding direction of the sheet to send out the sheet, can blow air in a direction perpendicular to the feeding direction of the sheet, or can blow air to the upstream side in the feeding direction of the sheet. It may be one that blows out air, may be one that blows out air in a direction perpendicular to the feeding direction of the sheet, or may be one that blows out air to the upstream side in the feeding direction of the sheet. As a preferred embodiment, at least one of the narrowing parts has an inlet and an outlet of the sheet, and a mode in which the inlet and the outlet are connected by a wall part can be mentioned. In this case, it is preferable that the air discharge part blows out the air between the wall part and the sheet. With this air, the adhesion between the wall part and the sheet can be prevented, and the conveyance can be assisted. As an example in FIG. 15, an air discharge part 13 provided in a trapezoidal box 7 is shown. In FIG. 15, the air discharge part 13 is provided at the upper part of the trapezoidal box 7, but it is not limited to this, and the air discharge part 13 may be provided between the inlet and the outlet of the trapezoidal box 7.

[0068] As another example of the narrowing assistance part, a mode of a driving or non-driving roll or a belt conveyor provided between the inlet and the outlet of the narrowing part can be mentioned.

[0069] [Introduction part] The narrowing device of the present embodiment may further have an introduction part provided on the upstream side in the feeding direction with respect to the narrowing part to introduce the sheet to the downstream side. Specifically, as the introduction part, a belt conveyor, a belt dryer, a drum dryer, or an unwinder can be mentioned.

[0070] The belt dryer forms the sheet by dehydrating and drying the raw material slurry of the sheet, and continuously introduces the formed sheet, and a known one can be used. The drum dryer rotates the drum on the heated drum surface while supplying the raw material slurry of the sheet, evaporates the raw material slurry and adheres it to the thin film on the drum surface, and continuously discharges the formed thin film by peeling it from the drum surface. A known one can be used. The unwinder is a device for unwinding the sheet wound around the roll.

[0071] Hereinafter, a preferred example of the narrowing device of the present embodiment will be described with reference to the drawings. Note that the configuration of the following embodiment is an example, and the present invention is not limited to the configuration of the following embodiment.

[0072] The narrowing device shown in FIG. 16 includes an introduction part, a narrowing part, and a conveying part in this order. The introduction part is a belt dryer 14, the narrowing part is a trapezoidal box 7 having an inlet 71, an outlet 72, and a wall part 73 of the sheet 1, and the conveying part is a nip roll 2. The width of the outlet is smaller than the width of the sheet 1, and the width of the sheet 1 is narrowed by this configuration. The direction in the width direction of the sheet 1 introduced from the belt dryer 14 and the direction of the rotation axis of the nip roll 2 may be parallel, but the rotation axis of the nip roll 2 may form a predetermined angle with the width direction of the sheet 1 and may be perpendicular.

[0073] The narrowing device shown in FIG. 17 includes an introduction part, a plurality of narrowing parts, and a conveying part in this order. The introduction part is a drum dryer 15, the narrowing part is an annular wire 10, and the conveying part is a single-sided roll. After the width of the sheet 1 is narrowed by the annular wire 10, it passes between the drive roll 3 and the wall 31 and is discharged.

Example

[0074] Using a narrowing device having a combination of the introduction part, the narrowing part, the conveying part, and, if applicable, the narrowing auxiliary part described in the table, the narrowing of a sheet having a weight ratio of microfiber cellulose / rubber component of 20 / 100 was performed. Note that the narrowing devices of Examples 1, 3, and 5 are shown in FIG. 16 It is the same as the narrowing device. Also, the two-stage hopper used in Examples 10-12 is obtained by replacing the trapezoidal box 7 arranged in series shown in Fig. 8 with the hopper 7'. Further, the first and second belt conveyors in Example 28 are those described in Fig. 6. As the rubber component, hydrogenated nitrile rubber (HNBR) was used in Examples 1-6 and Comparative Examples 2 and 3, nitrile rubber (NBR) was used in Examples 7-12, and natural rubber (NR) was used in Examples 13-29 and Comparative Example 1.

[0075] As the subsequent process of the narrowing device, a crushing process was performed using a film / sheet crusher (HW series, manufactured by Daitatsu Seiko Factory). The results of the comprehensive evaluation based on the following criteria are shown in Tables 1-6. In the tables, "arranged perpendicular to the width direction of the sheet" means that a pair of nip rolls are arranged such that the angle formed by the width direction of the sheet introduced into the pair of nip rolls and the rotation axis direction of the pair of nip rolls is 90°. 1: Impossible to crush 2: Can be crushed, but a large crusher is required 3: Can be crushed, and a small crusher can be used

[0076]

Table 1

Table 2

Table 3

Table 4

Table 5

Table 6

Table 7

[0077] As shown in Tables 1 to 7, by using the narrowing device according to the present invention, it is possible to narrow the width of the sheet. As a result, the size of the device used in the subsequent process can be reduced, and the manufacturing cost can be reduced. Examples 1, 2, 26, and 27 are examples in which the direction in which the nip rolls of the conveying unit are arranged is different. From these examples, it can be seen that arranging the sheet width direction and the rotation axis direction of the pair of nip rolls at a predetermined angle rather than parallel to each other results in a smaller ratio of the sheet width after discharge to the sheet width before introduction, and a smaller crusher can be used. Furthermore, it can be seen that the larger the angle formed, the smaller the ratio of the sheet width after discharge to the sheet width before introduction.

Explanation of Signs

[0078] 1 Sheet 2 Pair of nip rolls 3 Driving roll 31 Wall 4 Suction part 41 Suction port 42 Discharge port 5 Air discharge part 51 Air discharge port 6 Pair of belt conveyors 7 Trapezoidal box 71 Inlet 72 Discharge port 73 Wall part 7’ Hopper 71’ Inlet 72’ Discharge port 73’ Wall part 8 Pair of rolls 9 Pair of belt conveyors 10 Annular wire 11 Spirally arranged multi-stage rolls 12 Air gripper 13 Air discharge part 14 Belt dryer 15 Drum dryer

Claims

1. A narrowing device that has at least one conveying unit and at least one width-narrowing unit, and narrows the width of the sheet while feeding out the sheet, wherein the sheet contains cellulose fibers and a resin component, at least one of the conveying units is a pair of nip rolls, and the pair of nip rolls is arranged such that the angle formed between the width direction of the sheet introduced into the pair of nip rolls and the rotation axis direction of the pair of nip rolls is 10° or more. The narrowing device.

2. The narrowing device according to claim 1, wherein the sheet contains cellulose fibers and a rubber component.

3. The narrowing device according to claim 1 or 2, wherein at least one of the conveying units is provided on the downstream side in the feeding direction with respect to the width-narrowing unit.

4. The narrowing device according to claim 1 or 2, wherein at least one of the width-narrowing units has an inlet for the sheet and an outlet, and the width of the outlet is smaller than the width of the sheet.

5. The narrowing device according to claim 4, wherein the inlet and the outlet are connected by a wall portion.

6. The narrowing device according to claim 1 or 2, wherein at least one of the width-narrowing units is at least a pair of driving or non-driving rolls, and the rolls forming a pair are spaced apart with a predetermined distance in the width direction of the sheet.

7. The narrowing device according to claim 1 or 2, wherein at least one of the width-narrowing units is a pair of belt conveyors, and the distance between the pair of belt conveyors is arranged to become smaller as it goes downstream in the feeding direction.

8. The narrowing device according to claim 1 or 2, wherein at least one of the width-narrowing units is an annular wire, a multi-stage roll arranged in a spiral shape, or an air gripper.

9. The narrowing device according to claim 1 or 2, wherein a width-narrowing assisting unit is provided in the width-narrowing unit.

10. The width-narrowing assisting unit is an air discharge unit, at least one of the width-narrowing units has an inlet for the sheet and an outlet, and the inlet and the outlet of the width-narrowing unit are connected by a wall portion. The narrowing device according to claim 9.

11. At least one of the width-narrowing units has an inlet for the sheet and an outlet, and the width-narrowing assisting unit is a driving or non-driving roll or a belt conveyor provided between the inlet and the outlet. The narrowing device according to claim 9.

12. The narrowing device according to claim 1 or 2, further comprising an introduction part provided upstream in the feeding direction with respect to the narrowing part, for introducing the sheet to the downstream side.

13. The narrowing device according to claim 12, wherein the introduction part is a belt conveyor, a belt dryer, a drum dryer, or an unwinder.

14. A method for manufacturing a sheet, comprising a narrowing step of narrowing a sheet containing a cellulosic fiber and a resin component, using the narrowing device according to claim 1 or 2.

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