Fiberboard and laminates

Abstract

To provide fiberboard and laminates using the same that have practical strength and good cushioning properties while reducing environmental impact. [Solution] The resin fiber 1 comprises an inner layer 11 and an outer layer 12, and includes either recycled fibers or discharged yarn, or both. The outer layer 12 of the resin fiber 1 melts and solidifies, while the inner layer 11 and the recycled fibers or discharged yarn 2 intertwine without melting, so that the whole becomes one. As a result, the inner layer 11 of the resin fiber 1 and the recycled recycled fibers or discharged yarn 2 intertwine, giving it practical strength and good cushioning properties.

Description

Technical Field

[0001] The present invention relates to a fiberboard using fibers as a main raw material and a laminate using the same.

Background Art

[0002] Conventionally, flat fiberboards formed by accumulating natural fibers or chemical fibers have been used as heat insulating materials, curing materials, soundproof materials, and the like. These fiberboards are manufactured by forming a fibrous sheet called a web through production methods such as a dry method, a wet method, and a spunbond method, and then cutting the web into a predetermined length. In the forming of a web, the strength is improved by bonding fibers to each other. Bonding methods between fibers include a chemical bonding method using an adhesive, a thermal bonding method that thermally fuses fibers together, as well as a needle punching method and a spunlace method that bond fibers by entangling them with each other.

[0003] As fiberboards for industrial materials, chemical fibers are often used from the viewpoint of strength. On the other hand, in addition to chemical fibers as virgin materials, regenerated fibers that have been restored to a cotton-like fiber raw material state for the purpose of recycling fiber products are also used as fiber raw materials. By reducing the proportion of virgin petroleum-derived chemical fibers, the product becomes environmentally friendly.

[0004] For example, Patent Document 1 discloses a technology for a method of manufacturing fiberboard using recovered fibers. In the technology of Patent Document 1, a thermoplastic resin that melts at a temperature lower than the melting point of the recovered fibers is used as a binder material, and the recovered fibers are bonded to each other by hot pressing. Specifically, it includes the steps of heating a plurality of mats to serve as fiberboard respectively to melt the thermoplastic resin, stacking them while transporting to form a laminated mat, and then pressing the laminated mat under pressure. It is stated that this enables the manufacture of fiberboard as a substitute material for wood.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2005-254695 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In the technology described in Patent Document 1, the thermoplastic resin, which acts as a binder, melts, and the molten binder penetrates between the recovered fibers and solidifies. Compared to a sheet material made only of thermoplastic resin, the recovered fibers are thought to play a role as fillers. However, using only recycled fibers as filler presented a problem: the overall elasticity of the board material was inferior.

[0007] This invention has been made in view of the above-mentioned problems, and its objective is to provide a fiberboard and a laminate using the same that have practical strength and good cushioning properties while reducing environmental impact. [Means for solving the problem]

[0008] The means employed by the inventors to solve the above problems are described below. The fiberboard of the present invention comprises resin fibers having an inner layer and an outer layer, and either or both of reclaimed fibers and loosened yarns. The outer layer of the resin fibers melts and solidifies, while the inner layer, reclaimed fibers, and loosened yarns intertwine without melting, forming a unified structure. Reclaimed fibers refer to fibers obtained by unraveling textile products such as clothing using a needle-like tool, returning them to their original fiber raw material state. Loosened yarns refer to fiber waste generated during fiber processing.

[0009] In fiberboard, the amount of virgin fiber material used can be reduced by including either or both recycled fibers and released yarn in addition to the virgin fiber material. Furthermore, in resin fibers comprising an inner layer and an outer layer, while only the outer layer melts, the inner layer remains as resin fibers and is integrated with the reclaimed fibers and release threads. Compared to a case where all the resin fibers melt and solidify, the inner layer remains as resin fibers, and the elastic force of the resin fibers provides good cushioning.

[0010] In order to solve the aforementioned problems, the present invention employs, in addition to the above-mentioned means, the combined weight ratio of the recycled fibers and the released yarn can be set to 50% or more and 90% or less of the total weight. By making the proportion of recycled fibers and released yarn equal to or greater than the proportion of resin fibers in virgin material, the proportion of recycled raw materials in fiberboard can be increased. Furthermore, by not using only recycled fibers and released yarn as raw materials, but combining them with virgin material, a decrease in the strength of the fiberboard can be prevented.

[0011] Another means employed by the present invention to solve the aforementioned problems is to provide a plate-shaped laminate comprising a base layer made of the above-mentioned fiberboard and a surface layer containing a nonwoven fabric laminated on the base layer. By laminating another nonwoven fabric as a surface layer onto a fiberboard containing either or both of the reclaimed fibers and the release yarn, in which the outer layer of the resin fibers melts and solidifies, and the inner layer, reclaimed fibers, and release yarn intertwine and become one without melting, the functionality of the surface nonwoven fabric can be imparted.

[0012] Reclaimed fibers and discarded yarns have irregular fiber arrangements and possess different textures and surface characteristics compared to virgin materials. Therefore, instead of using fiberboard containing these materials alone, laminating them with other nonwoven fabrics allows for the addition of various functionalities while retaining the environmentally friendly properties of fiberboard. For example, a nonwoven fabric with high anti-slip properties can be laminated to the surface as a non-slip surface layer.

[0013] In order to solve the aforementioned problems, another means adopted by the present invention is, in addition to the above configuration, that the basic layer may be made of a polyethylene terephthalate-based resin and the surface layer of a nonwoven fabric made of a polyethylene terephthalate-based resin. Polyethylene terephthalate is a polyester-based thermoplastic paper resin, and its recycling methods and distribution channels are well-established in the market.

[0014] Since both the fiberboard and the surface layer are composed of polyethylene terephthalate-based resin, there is no need to separate the materials during recycling. Therefore, the processing when recycling the laminate itself is simplified, and costs can be reduced.

[0015] Another means employed by the present invention to solve the aforementioned problems is that a laminate layer may be provided at the contact surface between the surface layer and the basic layer. By having a laminate layer between the base layer, which is made of fiberboard, and the surface layer, which is made of nonwoven fabric, it is possible to prevent moisture from penetrating the base layer while maintaining the functionality of the surface layer. [Effects of the Invention]

[0016] As described above, the fiberboard and laminate of the present invention contain either or both recycled fibers and discharged yarns, and have a fiberboard in which the outer layer of resin fibers is melted and solidified, while the inner layer, recycled fibers, and discharged yarns are intertwined and integrated without melting. As a result, the inner layer of resin fibers and recycled fibers intertwine, providing practical strength and good cushioning properties. Furthermore, because only the outer layer is melted, the inner layer, recycled fibers, and discharged yarns can be easily separated and recycled, thus reducing the environmental impact. [Brief explanation of the drawing]

[0017] [Figure 1] This is a cross-sectional view showing the fiberboard of the present invention. [Figure 2] This is an explanatory diagram illustrating the method for manufacturing fiberboard according to the present invention. [Figure 3]It is a cross-sectional view illustrating the laminate of the present invention. [Figure 4] It is an explanatory view illustrating the method for producing the laminate of the present invention. [Figure 5] It is a cross-sectional view illustrating the laminate in Modification 1 of the present invention. MODE FOR CARRYING OUT THE INVENTION

[0018] A mode for carrying out the present invention will be described below based on FIG. 1. Each drawing is schematically illustrated for explanation, and dimensions and shapes are partially emphasized or simplified.

[0019] As shown in FIG. 1, the fiberboard 100 of the present invention is a flat plate material, and is constituted by various long and short fibers intricately intertwined with each other. The fiberboard 100 can be used, for example, as a curing material when carrying equipment into a house, and can also be used as an industrial material such as a heat insulating material or a soundproofing material. These fibers include resin fibers 1 and reclaimed wool or discharged yarn 2.

[0020] As shown in FIG. 1, the resin fiber 1 includes an inner layer 11 and an outer layer 12. Various materials can be used as the material of the resin fiber 1, and chemical fibers can be used from the viewpoints of resistance to deterioration, strength and durability. Examples include polyester resins such as polyethylene terephthalate (PET), polypropylene resin (PP), polyethylene resin (PE), polyamide resin (PA), etc., and PET can be preferably used because of its ease of recycling. Here, a material that melts at a higher temperature for the inner layer 11 than the outer layer 12 is selected. For example, PET that melts at 170°C is used for the outer layer 12, and CO-PET (a mixture of PET and a copolymer) that melts at 220°C is used for the inner layer 11. Thereby, only the outer layer 12 is melted, and the inner layer 11 is not melted and can remain as resin fibers.

[0021] The reclaimed wool or discharged yarn 2 is configured to include either or both of reclaimed wool and discharged yarn. Reclaimed fiber refers to textile products such as clothing that have been separated and cut, and then loosened by scratching them with a needle-like roller, returning them to their raw fiber state. By separating the types of materials during the sorting stage, it is possible to produce reclaimed fiber from a single material, but it is also possible to mix different types of reclaimed fiber. Furthermore, the maximum fiber length of the reclaimed fiber can be shortened or lengthened depending on the size of the cut pieces.

[0022] "Released yarn" refers to fiber waste generated during the processing of textiles, such as in textile raw material manufacturing plants and textile product factories. For example, in a spinning mill, it would be the accumulation of dust-like fibers that leak from the equipment during the yarn manufacturing process. In a knitting or weaving factory, it would be the accumulation of yarn scraps and other waste that have come loose from leftover materials. Even in released yarn, the type and length of fibers vary depending on the source. While it is possible to produce single-material released yarn by sorting, it is also possible to mix in other types of released yarn. Furthermore, fibers with short or long maximum fiber lengths can be mixed or unified.

[0023] These recycled fibers or release threads 2 may be used individually or mixed together. Here, the recycled fibers or release threads 2 are configured to intertwine with the resin fibers 1, 1, ... Specifically, the material is formed using a manufacturing method that does not employ chemical bonding methods, which involve chemical melting and fixing, or thermal bonding methods, which involve melting and fixing by heat. For example, as shown in Figure 2, after forming a web W from the fiber raw material by web molding, the fibers are physically intertwined using a needle punching machine N, and then heated so that only the outer layer 12 melts and becomes one. The material is then wound into a roll using a roll R. When used as a fiberboard 100, this wound roll is cut to a predetermined width.

[0024] If the resin fibers 1, 1… are completely melted and fixed, the fiberboard 100 itself becomes a single resin board, losing its cushioning and heat insulating properties. Therefore, in order to maintain the shape of the fibers by melting and fixing them, it is necessary to mix in another thermoplastic resin having a melting temperature lower than that of the resin fibers 1, 1… and then heat-mold it. However, if other thermoplastic resins with different melting temperatures are mixed together, it becomes difficult to separate the materials when the fiberboard 100 is to be recycled, making recycling impossible.

[0025] Therefore, a needle punching machine N equipped with special needles is used to entangle the resin fibers 1·1…, causing the outer layer 12·12… to melt, while the inner layer 11·11… and the reclaimed fibers and discharged threads are entangled and integrated without melting. This allows the outer layer 12 to be melted again to separate the materials. In particular, if both the inner layer 11 and the outer layer 12 are made of PET, the fiberboard 100 will be made from a single raw material resin fiber 1·1…. In that case, there is no need for sorting, and it becomes easier to recycle.

[0026] Here, since the recycled fibers or released yarn 2 often differ in length and how they are intertwined, when they are mixed together, they intertwine more intricately, increasing strength and increasing volume through a bulking effect. In particular, the combined weight ratio of recycled fibers and released yarn is preferably 50% to 90% of the total weight of the fiberboard 100, more preferably 60% to 80%, and even more preferably 65% ​​to 75%. Specifically, the proportion of recycled fibers can be greater than the proportion of released yarn; for example, the ratio can be 30% virgin material, 40% recycled fibers, and 30% released yarn.

[0027] The resulting fiberboard 100 has practical strength because only the outer layer 12 is melted, and the inner layer 11 and the reclaimed fibers or filamented yarn 2 are not melted or fixed together. Furthermore, the inner layer 11 provides cushioning, shock absorption, heat insulation, and sound insulation. Moreover, the inner layer 11 and the reclaimed fibers or filamented yarn 2 can be separated and recycled. In addition, if it is composed of a single raw material, it can be melted and recycled as is, thereby reducing the environmental burden.

[0028] The fiberboard 100 described above can be made more functional by laminating it with other materials to form a laminate. The laminate 200 shown in Figure 3 is formed by laminating a nonwoven fabric 3 as the surface layer onto a base layer using the laminate 100 shown in Figure 1. The nonwoven fabric 3 is sufficiently thin compared to the resin board 100 and can be composed solely of virgin material, without containing reclaimed fibers or discharged yarns 2. Similar to the fiber board 100, the material for the nonwoven fabric 3 can be polyester resins such as polyethylene terephthalate (PET), polypropylene resin (PP), polyethylene resin (PE), polyamide resin (PA), etc., but PET is preferably used due to its ease of recycling. However, the nonwoven fabric 3 may also contain reclaimed fibers or discharged yarns 2.

[0029] The nonwoven fabric 3, which forms the surface layer, can have a variety of surface properties. For example, by making the surface glossy, it becomes easier to wipe away dirt and easier to remove dust and debris with a vacuum cleaner. In addition, by applying a non-slip treatment, anti-slip properties can be provided. Because the base layer uses recycled fibers and loose yarns, the surface is prone to pilling, making it difficult to remove dirt and debris, and the texture may be inferior. Therefore, by providing a surface layer made of a separate nonwoven fabric 3, as in the laminate 200 of the present invention, various functionalities can be imparted.

[0030] Even in this case, since the nonwoven fabric 3 is laminated to the base layer, it is easy to separate and recycle. Furthermore, if it is made of the same material as the laminated board 100 which is the base layer, it can be recycled as is without separation.

[0031] The laminate 200 can be manufactured by the method shown in Figure 4. The nonwoven fabric 3, which forms the surface layer, can be manufactured by the needle punch method, similar to the fiberboard 100, which forms the base layer. In the nonwoven fabric 3, the fibers are not melted or fixed together, but rather entangled and integrated, making it easier to recycle. In addition to the needle punch method, the spunlace method and other methods can also be used to manufacture the nonwoven fabric 3.

[0032] The fiberboard 100 and the nonwoven fabric 3 are pressed together using a press machine P, and then placed in a drying oven H. The temperature of the drying oven H is set to a temperature that does not cause the fibers to melt. Heating in the drying oven H allows the surface layer and the base layer to blend together, improving adhesion.

[0033] "Variations" Next, Figure 5 shows a modified example of the present invention. The laminate 201 in the modified example of the present invention differs from the laminate 200 in Figure 3 in that it has a laminate layer 4 between the surface layer and the base layer. The laminate layer 4 is a layer made of a very thin resin film, and like the fiberboard 100, the material used for it can be polyester resins such as polyethylene terephthalate (PET), polypropylene resin (PP), polyethylene resin (PE), polyamide resin (PA), etc.

[0034] Since the nonwoven fabric 3 of the surface layer and the resin plate 100 of the base layer have voids between the fibers because the fibers are not fused together. Therefore, if a large amount of moisture adheres to them, it will permeate through the gaps between the fibers and seep in. Therefore, by providing a film-like laminate layer 4 between the surface layer and the base layer, a waterproof function can be provided that prevents moisture from penetrating from the nonwoven fabric 3 of the surface layer to the resin plate 100 of the base layer. At this time, a small amount of moisture will seep into the surface layer, but since the surface layer is a very thin layer, moisture and dirt can be easily wiped away.

[0035] The present invention is not limited to the embodiments described above, and can be modified as appropriate within the scope of the claims of the present invention. For example, instead of providing the laminate layer between the surface layer and the base layer, it may be provided on the surface of the resin plate without providing a surface layer. Furthermore, it is possible to laminate two or more resin plates containing reclaimed fibers or release yarn 2 and resin plates that do not contain reclaimed fibers or release yarn 2, or to laminate multiple resin plates with different mixing ratios.

[0036] As described above, the fiberboard and laminate of the present invention include resin fibers having an inner layer and an outer layer, and either or both recycled fibers and discharged yarns, wherein the outer layer of the resin fibers melts and solidifies, while the inner layer, recycled fibers, and discharged yarns do not melt and become intertwined, resulting in a fiberboard that is integrated as a whole. As a result, the inner layer of the resin fibers and the recycled fibers become intertwined, providing practical strength and good cushioning properties. Furthermore, since only the outer layer melts and the inner layer and recycled fibers do not melt, the fiberboard and laminate themselves are easy to recycle, thereby reducing the environmental burden. [Explanation of Symbols]

[0037] 100 resin plates 200,201 laminate 1. Resin fiber 11 Inner Layer 12 Outer layer 2. Recycled yarn or released yarn 3 Nonwoven fabric 4. Laminating layer

Claims

1. A fiberboard comprising resin fibers having an inner layer and an outer layer, and either or both of reclaimed fibers and release threads, wherein the outer layer of the resin fibers melts and solidifies, while the inner layer, reclaimed fibers, and release threads intertwine without melting, and the whole is integrated.

2. The fiberboard according to claim 1, characterized in that the combined weight ratio of recycled fibers and released yarn is 50% or more and 90% or less of the total weight.

3. A plate-shaped laminate, A basic layer consisting of a fiberboard as described in claim 1 or claim 2, A surface layer including a nonwoven fabric laminated on the aforementioned base layer, A laminate comprising the following features.

4. The aforementioned basic layer is a polyethylene terephthalate-based resin. The laminate according to claim 3, characterized in that the surface layer is composed of a nonwoven fabric which is a polyethylene terephthalate resin.

5. The laminate according to claim 3, characterized in that the contact surface between the surface layer and the base layer is provided with a laminate layer.

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