JP2005254695A - Manufacturing method of fiberboard and its manufacturing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of effectively mass-producing a thick fiberboard having a gradient function as a replacement material of timber. <P>SOLUTION: The manufacturing method of the fiberboard for manufacturing the fiberboard as the replacement material of the timber by mixing recovered fiber and a thermoplastic resin melted at a temperature lower than a melting point or a thermal deterioration temperature of the recovered fiber to form a mat and heat-pressing it comprises a preliminarily heating process (a step S110) of heating each of a plurality of the mats to melt the thermoplastic resin, a lamination process (a step S120) of stacking the mats each containing the molten resin while transferring the mats to produce a laminated mat, and a pressing process (a step S130) of continuously pressing the laminated mats. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a technology of a fiberboard manufacturing method using recovered fibers as a raw material, and more particularly to a manufacturing method for efficiently mass-producing a fiberboard having a large thickness and a tilt function.

  Conventionally, there is a technology that uses fiber-based materials as raw materials and composites them with plastics (thermoplastic resin / thermosetting resin) or rubber to make sheet-like or plate-like functional materials with a certain rigidity and elasticity. It is publicly known. In such a manufacturing technique, it is common to melt a mixed thermoplastic resin to adhere a fibrous material and solidify it into a sheet or the like by a pressure press.

  On the other hand, in recent years, from the viewpoint of protecting environmental resources, recycling and reuse of waste, including plastic recycling, has attracted attention. Technology that produces wood substitute materials from waste such as waste fibers (textile products such as used clothes, curtains and sheets (boro), and cutting waste, woven fabric, yarn waste, cotton waste, etc.) is drawing attention is there.

  In particular, waste fibers are mainly used as waste, used clothing for export overseas, used clothing for domestic sale, or recycled as recovered fiber (recycled cotton) or special spinning. The range of applications for reuse is narrow, and many are incinerated or industrially disposed. For this reason, research and improvement of new technologies relating to the reuse of these late fibers are awaited.

  So far, for example, techniques described in Patent Documents 1 to 3 have been proposed from the viewpoint of manufacturing and reusing a wood substitute material from wood and waste fibers.

Specifically, in Patent Document 1, a belt-like mat obtained by mixing natural fibers containing wood flour with a thermoplastic resin is inclined and overlapped, and then hot-pressed in the thickness direction to obtain a fiber board as an artificial wood. A manufacturing technique is disclosed (see Patent Document 1).
Further, in Patent Document 2, a knitted fabric is prepared from two types of fiber scraps having different melting points, and a high melting point knitted fabric is laminated in advance so as to be sandwiched between low melting point knitted fabrics, and this is heated with a mold. Thus, a technique for manufacturing an integral fiber laminate has been proposed (see Patent Document 2).
Furthermore, in patent document 3, the technique which manufactures a fiber mixed resin is proposed by heating and extruding so that the low melting-point resin in a piece-like or web-like carpet cutting waste may be melted (patent). Reference 3).

JP 2000-190311 A JP 2000-334873 A Japanese Patent Laid-Open No. 10-286886

  Certainly, according to the technologies disclosed in Patent Document 1 to Patent Document 3 described above, it becomes possible to manufacture fiberboards and fiber mixed resins using natural fibers, fiber scraps, and the like as raw materials. It can be said that it was useful as a means to increase the utility value of the late fibers, etc.

  However, considering the utility value as a wood substitute material on an industrial basis, the manufactured fiberboard can be easily mass-produced with the same quality, and has a wide range of functions such as having a tilt function. It should be applicable to various needs. Therefore, the conventional fiberboard manufacturing method has the following problems.

  Specifically, in the production of conventional fiberboards and fiber-mixed resins, press molding mainly by mold pressing or extrusion molding has been performed. Therefore, it is difficult to increase the size of the manufacturing apparatus, and the size of the fiberboard to be manufactured is limited. Moreover, the process of stopping the transfer by a conveyor or the like and taking out the pressed fiberboard is required, resulting in poor production efficiency. For example, according to the die press, it is possible to manufacture a fiberboard or the like having a gradient function having different functions between layers (see Patent Document), but there are problems as described above.

  Furthermore, according to the manufacturing method in which the thermoplastic resin is melted by hot pressing in the thickness direction, the melting rate of the thermoplastic resin differs between the surface portion and the inside, and it takes time to completely melt the thermoplastic resin. It was. For this reason, it has been difficult to quickly produce a fiberboard of constant quality in which the thermoplastic resin is uniformly melted or a fiberboard that is large in the thickness direction.

  Therefore, the present invention relates to a fiberboard manufacturing method and a manufacturing apparatus therefor, which solves the above-mentioned conventional problems, enables the rapid and mass production of the same quality fiberboard, has a large thickness and has an inclination function. The purpose is to efficiently mass-produce fiberboard.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, as a fiberboard manufacturing method, fibers for manufacturing a fiberboard as a wood substitute material by hot pressing a mat mixed with recovered fibers and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fibers A method for manufacturing a plate, comprising: a preheating step of heating a plurality of mats to melt a thermoplastic resin; and a laminating step of superimposing a laminated mat while transferring a mat in a state where the thermoplastic resin is melted. And a press molding step of continuously pressing the laminated mat under pressure.

  Further, a fiberboard manufacturing method for manufacturing a fiberboard as a wood substitute material by heating and pressing a mat mixed with a recovered fiber and a thermoplastic resin that melts at a temperature lower than a melting point or a heat deterioration temperature of the recovered fiber, It consists of a preheating process in which a laminated mat in which a plurality of mats are laminated in advance is heated to melt the thermoplastic resin, and a press molding process in which the laminated mat in a state where the thermoplastic resin is melted is continuously pressed. Is.

  In the preliminary heating step, it is preferable that hot air is blown from the upper side or the lower side of the mat and sucked from the lower side or the upper side to melt the thermoplastic resin in the mat. In the laminated mat, the mixing ratio of the thermoplastic resin in at least one mat may be different from the mixing ratio of the thermoplastic resin in the other mats. The anti-bristles of the included fabric can be used. Furthermore, the thickness of the fiberboard manufactured by the above manufacturing method is in the range of 1 mm to 90 mm.

  On the other hand, as a fiberboard manufacturing device, a mat mixed with recovered fibers and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fibers is heated and pressed to manufacture a fiberboard as an alternative material for wood. An apparatus for manufacturing a fiberboard, comprising: a heating machine that heats a mat by a plurality of conveyors arranged in multiple stages; and a mat that is connected to the heating machine and in which a thermoplastic resin is melted. A laminating conveyor that is superposed while being transferred to form a laminating mat and a pressure roll that continuously presses the laminating mat are provided.

  Also, a fiberboard manufacturing apparatus for manufacturing a fiberboard as a wood substitute material by hot pressing a mat mixed with recovered fibers and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fibers. A heating machine that heats a laminated mat in which a plurality of mats are laminated in advance while being conveyed by a conveyor, and a pressure roll that continuously presses and presses the laminated mat in a state where a thermoplastic resin is melted. It is.

  The heater preferably includes at least a pair of hot air blowing ports and suction ports capable of simultaneously heating a plurality of mats on the upper side or the lower side of the mat.

  As effects of the present invention, the following effects can be obtained.

  That is, it is divided into a plurality of mats and the thermoplastic resin of each mat is uniformly melted in a short time, and as a result, a thick fiberboard can be efficiently produced in a short time. In addition, since the heating conditions can be changed for each mat, mats having different types of recovered fibers and thermoplastic resins, mixing ratios, and the like can be used. As described above, it is possible to quickly and in large quantities produce a fiberboard having a large thickness and a fiberboard having an inclination function, which has been difficult in the past, with the same quality. This reduces the manufacturing cost of the fiberboard, and the fiberboard can be manufactured as an industrial base as a wood substitute material.

  In addition, since the laminated mat in which a plurality of mats are laminated in advance is heated and pressed continuously, the pressing can be performed immediately after the thermoplastic resin in the laminated mat is melted. The manufacturing process can be simplified.

  In addition, since the hot air is passed through the mat in the preheating step, the thermoplastic resin can be melted uniformly and in a short time, and a fiberboard having a constant quality can be rapidly produced. And a continuous and automatic manufacture of a fiber board is attained by carrying out a lamination process and a press molding process continuously, and it can mass-produce.

  Moreover, the fiber board which changed surface property and internal property can be obtained. That is, in the fiberboard, a mat with a small amount of thermoplastic resin (or a small basis weight) is sandwiched between mats with a larger amount of thermoplastic resin (or a larger basis weight), and cushioning on the surface. It is possible to impart a tilting function such as imparting.

  In addition, the bristles obtained by loosening the rags are soiled compared to the original fibers, and the fiber length is shortened by cutting, so that the recovered fibers are used. This is consistent with the point of view of new recycling and reuse of waste fibers, etc.

  Furthermore, for example, if a fiberboard (pseudo-tree) as a wood substitute material such as a packing material can be manufactured, the conventional packing material made of coniferous trees requires fumigation disinfection such as measures against pine worms. This eliminates the need for packing materials and simplifies the process. Furthermore, it is excellent in terms of reducing the deforestation and protecting the global environment.

Next, a fiberboard manufacturing method and a manufacturing apparatus thereof according to the present invention will be described with reference to the embodiment shown in FIGS.
FIG. 1 is a flowchart showing a fiberboard manufacturing method according to an embodiment of the present invention, FIG. 2 is a flowchart showing a fiberboard manufacturing method according to another embodiment of the present invention, and FIG. 3 is a diagram of a fiberboard according to the present invention. It is the side view which showed the whole structure of the manufacturing apparatus.

[About recovered fibers]
The recovered fiber as a raw material is a fiber secondary processed product of waste fibers, that is, fabrics such as woven fabrics, knitted fabrics, and nonwoven fabrics that constitute used clothing, furoshiki, towels, sheets, curtains, etc. This refers to fiber that has been collected by loosening collected products (so-called rags), and fiber waste such as cutting waste, woven fabric, yarn waste, and cotton waste discharged from spinning and weaving factories. In particular, the bristles obtained by loosening the rags are dirty as compared to the original fibers, and have the characteristics of fibers except that the fiber length is shortened by cutting. Therefore, from the viewpoint of recycling and reuse of the fiber waste, it is preferable to reuse the fabric bristles contained in the general waste.

  The type of fiber as the recovered fiber is not particularly limited, and plant fibers such as cotton and hemp, animal fibers such as wool, regenerated fibers such as rayon, synthetic fibers such as polyester and acrylic, and semisynthetic fibers such as acetate are used. be able to. These may be used alone or in combination of two or more.

[About thermoplastic resin]
Examples of thermoplastic resins include olefin resins such as polyethylene and polypropylene, acrylic resins such as polyamide and polyacrylonitrile, and polyester resins such as polyethylene terephthalate. These thermoplastic resins may be used alone or in combination of two or more.

  Since the thermoplastic resin is used as a binder for the recovered fiber, it is preferable to melt the thermoplastic resin at a temperature lower than the melting point or the heat deterioration temperature of the recovered fiber. Here, the temperature at which the recovered fiber does not deteriorate refers to a temperature at which the recovered fiber does not melt when the recovered fiber is a synthetic fiber, and a temperature at which the recovered fiber does not become scorched or shabby when the recovered fiber is a natural fiber. Specifically, it is about 250 ° C. for cotton fibers, about 260 ° C. for polyester fibers, about 210 ° C. for wool, and about 220 ° C. for acrylic fibers. As described above, although the degradation temperature of the recovered fiber depends on the composition, it is usually higher than 200 ° C., and therefore, it is preferable to use a thermoplastic resin having a melting point of 200 ° C. or less. Examples of such thermoplastic resins include polyethylene, polypropylene, low-melting point polyester, low-melting point polyamide, etc. Among them, polypropylene is preferably used from the viewpoint of high rigidity and a large amount of recovery in a long fiber state. .

  The shape of the thermoplastic resin is not particularly limited. For example, in addition to a fiber shape, a particle shape such as powder, pellets, and flakes can be used. Among them, a preferable shape as the binder is a fiber shape having an average fiber length of 20 mm or more, more preferably 30 mm or more. This is because the fibrous thermoplastic resin is usually easily available as fiber waste generated from a fiber processing factory. On the other hand, if the fiber length is 20 mm or less, it is short and it is difficult to sufficiently entangle the fibers with the recovered fiber by mixing. However, if too long ones are used, the thermoplastic resin is less likely to be homogeneously dispersed throughout the mat due to the mixing ratio with the recovered fibers. As a result, the fiberboard produced is rich in thermoplastic resin. The physical properties such as the cutting property of the part are deteriorated as compared with other parts.

  In particular, when a fiber-shaped thermoplastic resin is used, if it is mixed with recovered fibers, the recovered fibers can be sufficiently entangled and uniformly dispersed, and the recovered fibers melt the recovered fibers. It is possible to partially join with the binder. Therefore, by forming a macro porous structure in which the entanglement between the recovered fibers is partially fixed, the fiberboard to be manufactured achieves high strength while maintaining light weight comparable to natural wood. Can do. In this regard, when a liquid binder is used, it is generally difficult to form a porous structure because it is immersed uniformly.

  In these thermoplastic resins, additives such as heat stabilizers, plasticizers, lubricants, antioxidants, UV absorbers, pigments, inorganic fillers, reinforcing short fibers, fillers, processing aids, etc. A modifier or the like may be added.

[About mat]
The mixing ratio of the recovered fiber and the thermoplastic resin in the belt-like mat in which the recovered fiber and the thermoplastic resin are mixed can be freely set. Preferably, the thermoplastic resin is 30 to 50 weights with respect to 100 parts by weight of the recovered fibers. Use parts. When the recovered fiber and the fibrous thermoplastic resin are mixed and sufficiently entangled with each other to form a web or a felt-like mat, if the amount is less than 30 parts by weight, the bonding area between the recovered fibers is reduced and the molded product is obtained. This is because the holding power of the nail driven into the fiberboard is insufficient, and the bending strength is inferior to that of ordinary wood. On the other hand, when the amount is 50 parts by weight or more, the ratio of the plastic portion of the fiberboard is increased, so that the interval between the recovered fibers becomes too small, and it is difficult to warp the nail. As the mixing mat, a mixing mat in which a thermoplastic resin is integrated in a film form, a sheet form, a powder form or any other form can be used as necessary.

Since a plurality of mats are laminated, the thickness and density can be appropriately set according to the target thickness of the fiberboard and the number of mats to be laminated. For example, when manufacturing a fiberboard having a thickness of 15 mm and a density of about 0.6 g / cm ³ , six mats having a basis weight of 1.2 kg / m ² and a thickness of about 15 mm are stacked, What is necessary is just to heat-compress to 1/6. Moreover, in order to manufacture a fiberboard having a thickness of about 60 mm, 24 sheets of the same mat may be stacked and heated and compressed to 1/6.

[About fiberboard]
The fiberboard manufactured according to the present embodiment has a density range of 0.2 to 1.0 g / cm ³ and a thickness of 1.0 mm to 150 mm. In particular, one example used as packing wood has standards such as fiberboard thicknesses of 12 mm, 25 mm, 45 mm, and 90 mm. However, according to the manufacturing method of the present embodiment, a fiberboard having an arbitrary thickness (pseudowood) ) Can be molded. Among them, the use as packing timber substitute material is preferably a density range is 0.5g / cm3~0.7g / cm ^3, a thickness of 1Mm～90mm. More preferably, the thickness is 10 mm to 70 mm. If the density is less than 0.5 g / cm ³ , a problem arises in strength, and if it is greater than 0.7 g / cm ³ , it becomes heavier and a weight problem arises. By using such a fiberboard (pseudo-tree), the conventional packing materials made from coniferous trees do not require fumigation and sterilization measures such as pine worms, reducing the cost of packaging materials and simplifying the process. Can be achieved. Furthermore, it is excellent in terms of reducing deforestation and protecting the global environment.

[Fiberboard manufacturing method]
The fiberboard manufacturing method according to the present embodiment is performed in the steps shown in FIGS.
FIG. 1 is a flowchart showing a manufacturing method for manufacturing a fiberboard by melting a thermoplastic resin in a mat, laminating a plurality of mats, and heating and pressing the mats.

[About collection and sorting of rags and fiber waste]
The collection and sorting of rags and fiber scraps are not limited in their means, but the characteristics of the obtained fiberboard also depend on the type of recovered fiber used as a raw material, so certain fibers such as cellulose -It is preferable to preliminarily select those made of wool, polyester, acrylic, etc., because a fiberboard for each type can be manufactured and its characteristics can be more reflected. In addition, when using rags such as clothes and furoshiki from general households as raw materials for recovered fibers, it is difficult to open at once if there is a large amount of these. It is preferable to cut them into pieces, and it is more preferable to disassemble them into yarn pieces in advance.

[Matte forming step (step S100)]
The recovered fiber and the thermoplastic resin are mixed to form a (mixed) mat (step S100). The mat forming method of the recovered fiber and the thermoplastic resin is arbitrary. For example, a fiber product such as clothing is cut to an appropriate length as the recovered fiber, and a fibrous thermoplastic resin as a binder is opened while opening the fiber. After mixing, both fibers are sufficiently entangled and formed into a web-like or felt-like mat. In this case, the method for intertwining both fibers is not particularly limited, and examples thereof include a needle punch method and a carding method. In particular, when reclaimed fibers are used as the recovered fibers and cotton-like fiber scraps are used as the thermoplastic resin, a felt-like mixed mat in which both fibers are intertwined almost uniformly is easily formed by needle punching. be able to.

[Preliminary heating step (step S110)]
The mat molded by the mat molding process (step S100) is heat-treated, and the thermoplastic resin in the mat is melted (step S110). The heating condition is appropriately set depending on the type of the recovered fiber and the thermoplastic resin, and is performed at a temperature equal to or higher than the melting point of the thermoplastic resin used as the binder, preferably 20 ° C. to 30 ° C. higher than the melting point of the thermoplastic resin. This is because the temperature at which the thermoplastic resin is melted is sufficient, but the recovered fiber is deteriorated or melted at a temperature higher than necessary.

  As a heating method, any method can be adopted. For example, the mat may be heated in an oven set to the temperature, or radiation heating by an infrared heater or a far infrared heater may be used. In particular, in the present embodiment, it is preferable to use suction-type hot air heating. That is, hot air is blown from the upper side or the lower side of the mat, and further hot air is sucked from the lower side or the upper side to melt the thermoplastic resin in the mat.

  As a general heating method, for example, there is a method of simultaneously melting a thermoplastic resin and press-molding a mat. However, with such a method, the melting rate and degree of the thermoplastic resin differ between the vicinity of the surface and the inside, so it is difficult to melt the thermoplastic resin uniformly and produce a fiberboard of constant quality in a short time. is there. Moreover, in normal hot air heating, hot air is blown onto the mat to heat it, but when the mat is particularly thick or bulky, it is uniformly heat-treated to melt the thermoplastic resin. Takes time.

  On the other hand, according to the suction-type heating method in which hot air is simultaneously blown and sucked on the upper and lower sides of the mat, since the hot air is passed through the mat, the thermoplastic resin can be melted uniformly and in a short time. Quality fiberboard can be manufactured quickly. In addition, unlike the heating press device, there is no need to repeatedly stop and start the mat transfer as the pressure plate slides up and down, and the thermoplastic resin is melted sequentially while simultaneously transferring the mat to the heating device. It becomes possible to make it. Therefore, the fiberboard can be continuously and automatically manufactured by mass production by continuing the lamination process (step S120) and the press molding process (step S130) described later.

  In this embodiment, since the pressure pressing is performed in a state where the thermoplastic resin is melted (step S131), the press molding process (step S130) is performed immediately after the main heat treatment so that the thermoplastic resin serving as the binder can be thermally deformed. ) Is preferable.

  In the preheating step (step S110), the plurality of mats can be simultaneously heat treated to melt the thermoplastic resin in each mat. For example, when manufacturing a fiberboard having a large thickness, if a single mat is used as a raw material, a very thick mat is required. For this reason, it is necessary to increase the suction pressure, the apparatus becomes large, and it takes time to uniformly melt the thermoplastic resin in the mat. If each of the mats is divided into a plurality of mats and the thermoplastic resin of each mat is uniformly melted in a short time and then laminated, the resulting thick fiberboard can be efficiently produced in a short time. In addition, since the heating conditions can be changed for each mat, mats having different kinds and mixing ratios of the collected fibers and the thermoplastic resin can be used. Details of the mat type will be described later.

[Lamination process (step S120)]
Each mat is laminated in the thickness direction in a state where the thermoplastic resin in each mat is melted by the preheating process (step S110) (step S120). Although this lamination method is not particularly limited, for example, the conveyors are arranged in multiple stages in the vertical direction, and the mats are suspended on one end of each conveyor while being transported by placing the mats on the conveyor. Laminate each. In order to quickly move the mat to the press molding process (step S130), the lamination process (step S120) is interposed between the preheating process (step S110) and the press molding process (step S130). It is done continuously. In order to maintain the molten state of the thermoplastic resin, it is preferably performed in the heating space.

  Here, in the stacking step (step S120), the same type of mats may be stacked, or different types of mats may be stacked. Here, the same type means a mat having the same mixing ratio of the recovered fiber and the thermoplastic resin, the type of fiber, the basis weight, etc., and the different type means a mixing ratio of the recovered fiber and the thermoplastic resin, This means that at least one of type, basis weight, etc. is different. When laminating the same type of mat, it is possible to produce a fiberboard with a large thickness, which was difficult in the past, and when laminating different types of mats, the surface properties and internal properties were changed. A fiberboard can be obtained. Furthermore, a mat with less thermoplastic resin (or a smaller basis weight) is sandwiched between mats with more thermoplastic resin (or a larger basis weight) to give cushioning to the surface, etc. The tilt function can be imparted.

[Press forming process (step S130)]
The press molding step (step S130) is divided into a step of pressing the laminated mat (step S131) and a step of cooling and solidifying (step S132).
First, the laminated mat is pressed to a predetermined thickness by a pressure pressing step (step S131). The method of pressurizing is not particularly limited, but a pressurizing roll is preferable in that the thickness of the fiberboard can be adjusted and the mat can be sequentially transferred to enable continuous production of the fiberboard.

  Moreover, when using a pressure roll, it is preferable to heat a pressure roll at the time of a press, and to set the temperature of the pressure roll to the temperature below melting | fusing point of a thermoplastic resin. This is because the laminated mat is transported in a state where the thermoplastic resin in the mat is melted, so that the mat (thermoplastic resin) can be prevented from being cooled and solidified when pressurized. At that time, the higher the pressure roll temperature, the better the expansibility. However, when the pressure roll temperature is equal to or higher than the melting point of the thermoplastic resin, the mat is likely to adhere to the roll surface. A metal roll may be used as the pressure roll, but in order to prevent the mat from adhering, it is preferable to use a roll whose surface is coated with a mat and a surface material having releasability. Furthermore, by providing unevenness parallel or intersecting with the surface of the pressure roller, it is possible to add an anti-slip function to the fiberboard surface.

  In the cooling / solidifying step (step S132), the cooling / solidifying method is not particularly limited. For example, a method such as air cooling / mist spraying or contact cooling using a roll or a belt can be used. In particular, a contact cooling method using a roll or a belt is preferable because the thickness of the obtained fiberboard can be easily adjusted. When a roller or a belt is used, the surface of the roller or the like may be coated with a surface material having a mat and releasability, and a coolant such as cooling water may be circulated inside. The laminated mat is cooled by such a cooling method until the thermoplastic resin in the mat is completely solidified. In addition, similarly to the pressurization press (step S131) described above, an anti-slip function can be added to the fiberboard surface by providing irregularities that are parallel to or intersecting the surface of a roller or the like.

  The fiberboard manufactured in this way starts from collection and sorting of rags and fiber waste, and through a mat forming process (step S100), in particular, a preheating process (step S110) for heat-treating the mat, and a laminating process (step S100). Step S120) and the press molding step (Step S130) can be performed continuously, and a fiberboard having a large thickness or a tilting function can be manufactured. Moreover, a long and large fiberboard in the longitudinal direction with respect to the mat width can be produced, and the fiberboard is useful as a wood substitute material having a wide application range by cutting with an appropriate length according to the purpose of use.

FIG. 2 is a flowchart showing a manufacturing method through a lamination process (step S220) in which the mats are laminated in the thickness direction before the preheating process (step S210) is started.
First, mats obtained by mixing the collected fibers and the thermoplastic resin formed by the mat forming step (step S200) are laminated in the thickness direction to be integrated into a laminated mat. In this case, it goes without saying that the same kind of mats may be laminated on the laminated mat, and different kinds of mats may be laminated together. Then, in the preheating process (step S210), for example, the thermoplastic resin in each mat of the laminated mat is melted by suction-type hot air heating, and then the pressurizing / pressing process (step S230) is performed. This is a method for producing a fiberboard by cooling.

  According to such a manufacturing method, since the mats are laminated in advance, the transfer time between the preheating process (step S210) and the press molding process (step S230) can be shortened, and the laminated mat is subjected to heat treatment. Immediately after the thermoplastic resin in each mat is melted, a pressure press can be performed. Further, in the stacking step (step S220), it is not necessary to stack mats in the heating space, and the apparatus configuration can be simplified.

[About fiberboard manufacturing equipment]
FIG. 3 shows an example of a fiberboard manufacturing apparatus 1 according to the present embodiment.
The manufacturing apparatus 1 includes a mat molding machine 10 that mixes recovered fibers and a thermoplastic resin to mold the mat 2, and a heater 20 that heat-treats the plurality of mats 2 to melt the thermoplastic resin in each mat 2. , Press forming having a laminating machine 30 having a laminating conveyor 32 provided continuously to the heater 20 and laminating in the thickness direction, and a pressurizing roller 43 being continuously provided to the laminating conveyor 32 to pressurize and cool the laminated mat 3 The machine 40 is comprised.

  The mat molding machine 10 can adopt any configuration. For example, the recovered fiber and the thermoplastic resin are cut to an appropriate length, mixed while opening, and laminated on the conveyor 11 with air or the like. A web-like mat 2 is formed. In order to change the web shape into a felt shape, the fibers in the web-like mat 2 are needling with a special needle so as to be entangled with each other. In the mat molding machine 10, the molding may be performed such that the mixing ratio of the thermoplastic resin in the mat 2 is different from the mixing ratio of the thermoplastic resin in the other mat 2, and the density of the mat 2 is changed. May be molded.

  In the manufacturing apparatus 1, the mat forming machine 10 is not an essential component, and the mat 2 formed by another apparatus may be transferred to the heating machine 20 of the manufacturing apparatus 1. When the mat molding machine 10 is connected to the heating machine 20, a fiberboard can be continuously produced simply by introducing the recovered fibers and the thermoplastic resin as raw materials into the mat molding machine 10, and therefore, it is preferably used.

  The heater 20 heats the mat 2 molded by the mat molding machine 10 to melt the thermoplastic resin in the mat 2. In the present embodiment, the heater 20 is provided with multi-stage mesh conveyors 22, 22... In parallel, so as to perform suction-type hot air heating on the mat 2 on each mesh conveyor 22. It is configured.

  The casing 21 formed of a heat insulating material so as to block heat exchange between the inside and the outside is partitioned in multiple stages in the vertical direction of the heater 20 (left and right direction in FIG. 3) (this embodiment) 3 stages). Mesh conveyors 22, 22, 22 are provided in the respective casings 21 a, 21 a, 21 a. Thus, by partitioning the inside of the casing 21 for each mesh conveyor 22, the heat treatment of the mat 2 can be performed efficiently. And by arrange | positioning the mesh conveyor 22 in multiple stages, the several mat | matte 2 can be heat-processed simultaneously by one manufacture, and an apparatus can be reduced in size.

  The mesh conveyor 22 may be only one stage. In such a case, for example, a plurality of mats 2 can be laminated in advance to form a laminated mat 3, and the laminated mat 3 can be transferred to the heater 20 to melt the thermoplastic resin in the laminated mat 3.

  The mesh conveyor 22 is continuous with the conveyor 11, and transfers the mat 2 formed by the mat forming machine 10 from the conveyor 11 to the housing 21 via the mesh conveyor 22. In the mesh conveyor 22, vertical and horizontal frames are entangled in a substantially mesh shape so that hot air can pass in the vertical direction inside the mat 2 in a state where the mat 2 is placed.

  A hot air blowing port 23 and a suction port 24 are opened at substantially symmetrical positions in the vertical direction of the mesh conveyor 22 on the inner wall of each housing 21a. Hot air heated by a heat source disposed on the outside of the casing 21 is blown into the casings 21a from the blowing port 23 via a duct or the like. Such hot air is adjusted to a temperature at which the thermoplastic resin in the mat 2 is melted and lower than the melting point or the heat deterioration temperature of the recovered fiber. When hot air is sucked from below the mesh conveyor 22 through the suction port 24, suction pressure is generated, and the hot air passes through the mat 2 while melting the thermoplastic resin in the mat 2. By setting it as such a structure, the thermoplastic resin in the mat | matte 2 can be fuse | melted quickly and uniformly, and the efficiency of heat processing improves.

  The blowing port 23 and the suction port 24 are not only opened on the inner wall of the housing 21 a, but, for example, a duct or the like protrudes from the inner wall of the housing 21, and the openings are the front and back surfaces of the mesh conveyor 22. You may make it open toward. Moreover, the number of the blowing inlet 23 and the suction opening 24 can be set arbitrarily, and is not restricted to the location (three locations) shown in FIG. For example, at least one pair of the air inlet 23 and the suction port 24 may be provided in the housing 21 without partitioning the housing 21.

  The laminating machine 30 includes a laminating conveyor 32 that is provided between the heating machine 20 and the press molding machine 40 and superimposes the mat 2 in a state where the thermoplastic resin is melted. In the present embodiment, the housing 21 (each housing 21 a) and the internal space of the housing 31 are continuous, and the heated air in the housing 21 circulates also in the housing 31. ing. A lamination conveyor 32 is connected to one end of each mesh conveyor 22, and the mat 2 transferred by the mesh conveyor 22 is quickly laminated by the lamination conveyor 32.

  By adopting such a configuration, the transfer distance between the heater 20 and the press molding machine 40 is shortened, and since the transfer is performed in heated air, the press molding is performed while the thermosetting resin is maintained in a molten state. Can be transferred to the machine 40. In addition, in the housing | casing 31, you may provide the discharge port (not shown) of a hot air separately through the duct from the heat source connected to a housing | casing, for example.

  Each mesh conveyor 22 is driven so as to transfer the mat 2 in the direction of the laminating machine 30 (rightward in FIG. 3, this direction is hereinafter referred to as X direction). A laminated conveyor 32 is connected to one end of the mesh conveyor 22, and the laminated conveyor 32 is also driven in the X direction. The lowermost conveyor layer 32 is disposed substantially horizontally, and the upper conveyor layer 32 is disposed such that the rear part in the transport direction is inclined toward the lowermost conveyor.

  The mat 2 transferred from the mesh conveyor 22 onto the stacking conveyor 32 has the right end portion 32a of the stacking conveyor 32 extending obliquely downward, and the guide of the mat 2 ends at the right end portion 32a and is suspended by its own weight. . That is, the right end portion 32a serves both as a conveyance and a guide. And when each conveyor 22 * 32 is driven, it will laminate | stack in order on the mat 2 on the lamination | stacking conveyor 32 of the lowest position. By adopting such a configuration, the laminated mat 3 can be formed immediately without an accompanying configuration, the multiple lamination process can be simplified, the production efficiency can be increased, and the manufacturing cost can be reduced.

  The press molding machine 40 is connected to the laminating machine 30 and connected to the laminating conveyor 32, and at least a pair of pressure rollers 43 and 43 arranged to face the upper and lower sides of the conveyor 42. , And a cooling mechanism 44 including a blower cooling device, a mist spray cooling device, and the like. It is preferable that the vertical distance between each pair of pressure rollers 43, 43... Is gradually reduced, and the mat 2 is not laterally extended when pressed. Has a guide (not shown).

  When the laminated mat 3 is transferred to the pressure roller 43 via the conveyor 42, the mat is conveyed while being pressed by the pressure roller 43 so that the laminated mat 3 has a predetermined thickness. The fiberboard is continuously manufactured by cooling and solidifying. Concavities and convexities that are parallel or intersect with the surface of the pressure roller 43 may be provided. The configuration of the cooling mechanism 44 is not particularly limited. For example, the endless belt 45 cooled by a blower cooling device, a mist spray type cooling device, or the like is driven by a rotating roller and pressed onto the laminated mat 3 pressed. The laminated mat 3 is cooled and solidified so as to abut.

The recovered fiber used was a batter of clothing discarded from ordinary households that was made into a bristles. Such recovered fiber contains 45% by weight of polypropylene as a thermoplastic resin. Each of the compositions in the recovered fiber was entangled uniformly by the needle punch method, and the weight per unit area was adjusted to 1.2 kg / m ² and the thickness was adjusted to 15 mm to form a felt-like mat. Other compositions in the mat are 30% cotton, 10% rayon and 15% polyester. In addition, the fiber length of polypropylene includes 70 mm to 15 mm, and the fiber thickness is 9D to 25D. Table 1 shows a summary of fiber lengths and fiber thicknesses of other compositions such as cotton and rayon.

  In Example 1, the mat is cut into an appropriate length, and six mats are preliminarily stacked to form a laminated mat, which is slightly lower than the melting temperature of the thermoplastic resin by a suction-type hot air heating machine. Heat treatment at a high temperature (about 195 ° C.). The heater transfers the laminated mat with a mesh conveyor and includes hot air blowing ports and suction ports on the upper and lower sides of the mat, respectively. Thereafter, the laminated mat was press-pressed with a pressure roller and cooled and solidified by a press molding machine.

  In Example 2 and Example 3, the mat was cut into an appropriate length, and four mats (Example 2) and eight mats (Example 3) were overlaid. Heating was possible, and heat treatment was performed at a temperature slightly higher than the melting temperature of the thermoplastic resin (about 195 ° C.) by a heater equipped with three stages of mesh conveyors. The heater transfers the laminated mat by each mesh conveyor in three stages, and includes a hot air blowing port and a suction port on the upper side and the lower side of the mat, respectively. After that, the mats were superposed while being transferred by a laminate conveyor to form a laminate mat, which was press-pressed with a pressure roller and cooled and solidified by a press molding machine.

Table 2 shows the thickness and compression rate of the manufactured fiberboard.
In Example 1, a fiberboard having a thickness of 12 mm could be produced. In Example 2, a fiber board having a thickness of 30 mm could be produced, and in Example 3, a fiber board having a thickness of 60 mm could be produced. Therefore, according to the present invention, it has become possible to continue and mass-produce a thick fiberboard using the recovered fiber as a raw material. Moreover, in Example 2 and Example 3, since this was made into three steps in the suction-type hot air heating, each mat was laminated and then heated and pressed as a laminated mat, so that a thick fiberboard was easily and quickly manufactured. did it. Further, any of the fiberboards of Examples 1 to 3 had excellent physical characteristics and could be sufficiently applied as a packaging wood substitute.

The flowchart which shows the manufacturing method of the fiber board which concerns on one Example of this invention. The flowchart which shows the manufacturing method of the fiber board which concerns on another Example of this invention. The side view which showed the whole structure of the manufacturing apparatus of the fiber board which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 10 Mat molding machine 20 Heating machine 30 Laminating machine 40 Press molding machine S100 Mat molding process S110 Preheating process S120 Lamination process S130 Press molding process S131 Pressure press S132 Cooling and solidification

Claims (9)

A method of manufacturing a fiberboard, in which a mat mixed with a recovered fiber and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fiber is heated to produce a fiberboard as a wood substitute material,
A preheating step of heating the plurality of mats to melt the thermoplastic resin,
A laminating step in which the mat in a state where the thermoplastic resin is melted is superposed while being transferred to form a laminated mat;
A press molding process in which the laminated mat is continuously pressed and pressed;
A method for producing a fiberboard comprising the steps of: A fiberboard manufacturing method for manufacturing a fiberboard as a wood substitute material by heating and pressing a mat mixed with a recovered fiber and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fiber,
A preheating step of heating a laminated mat obtained by laminating a plurality of mats in advance to melt the thermoplastic resin;
A press molding step of continuously pressing the laminated mat in a state where the thermoplastic resin is melted;
A method for producing a fiberboard comprising the steps of:   The said preheating process blows in hot air from the upper side or the lower side of the mat and sucks it from the lower side or the upper side to melt the thermoplastic resin in the mat. Of manufacturing fiberboard.   The method for producing a fiberboard according to claim 1 or 2, wherein the laminated mat has a mixing ratio of thermoplastic resins in at least one mat different from a mixing ratio of thermoplastic resins in other mats. .   The method for producing a fiberboard according to claim 1 or 2, wherein the recovered fiber is a fabric bristles contained in general waste.   A fiberboard manufacturing method, wherein the fiberboard manufactured by the fiberboard manufacturing method according to any one of claims 1 to 5 has a thickness of 1 mm to 90 mm. A fiberboard manufacturing apparatus for manufacturing a fiberboard as a wood substitute material by heat-pressing a mat mixed with recovered fibers and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fibers,
A heater that heats the mats by transferring them by a plurality of conveyors arranged in multiple stages;
A laminated conveyor that is connected to the heater and is superposed on the laminated mat while transferring the mat in a state where the thermoplastic resin is melted;
A pressure roll for continuously pressing and pressing the laminated mat;
An apparatus for producing a fiberboard, comprising: A fiberboard manufacturing apparatus for manufacturing a fiberboard as a wood substitute material by heat-pressing a mat mixed with recovered fibers and a thermoplastic resin that melts at a temperature lower than the melting point or heat deterioration temperature of the recovered fibers,
A heating machine that heats while transferring a laminated mat in which a plurality of mats are laminated in advance by a conveyor;
A pressure roll that continuously press-presses the laminated mat in a state where the thermoplastic resin is melted;
An apparatus for producing a fiberboard, comprising:   9. The fiberboard manufacturing apparatus according to claim 7, wherein the heater includes a hot air blowing port and a suction port capable of simultaneously heating a plurality of mats on an upper side or a lower side of the mat, respectively. .

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