JP2010208306A - Cushioning material containing parenchyma cell, and method for manufacturing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cushioning material that exhibits desired cushioning performance while reducing the usage of high-cost adhesive. <P>SOLUTION: The cushioning material 11 is obtained by mixing and molding fragments 2 of a cushioning material, an adhesive 4, and an alternative material of the adhesive. As the alternative material of the adhesive, bamboo parenchyma cells (especially, parenchyma cells adhering to the short fibers of bamboo) 3 are used. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cushion material and a manufacturing method thereof. Specifically, cushion materials (recycled products) that are applied to various cushion materials such as cushion materials for interior materials such as armrests of automobiles by using pieces of cushion materials (including recycled pieces of recycled cushion materials) And a manufacturing method thereof.

  For sheets with a large curvature, etc., this cushion material is cut into smaller pieces than normal cushion materials (for example, a single piece of polyurethane foam), and the pieces of this cushion material are compressed with an adhesive. Combined cushion materials (molded products) are suitable.

  Conventionally, as a method of manufacturing a cushion material using pieces of cushion material, a large amount of pieces of cushion material are put into a mold, and this is compressed and joined to a new block foam cushion material (mainly rebonding). Is known.

  In these conventional methods, a reactive curable adhesive (simply referred to as an adhesive) is used as a binder for compression bonding, and the pieces of cushion material are bonded together by reacting and curing the adhesive by steam or heating. Combined to obtain a cushioning material (mainly rebonding foam).

  For example, in the method for manufacturing a rebonding foam described in Patent Document 1, an adhesive is applied to chip-like scraps (cushion material of polyurethane foam) of polyurethane foam, and compression molding is performed to manufacture the rebonding foam (cushion material). A method has been proposed. Specifically, a urethane prepolymer containing 1 to 10% of unreacted isocyanate groups at the molecular end is used as an adhesive, and a piece of cushion material and the adhesive are mixed together and compression molded (compressed, steamed) And a method of heat-curing with the use of (a).

Japanese Patent Publication No.54-40590

  However, in the method described in Patent Document 1, since it is necessary to apply approximately 20 to 40 wt% of an adhesive in order to compress and compress the fragments of the cushion material, the molded cushion material is heavy. There was a problem of becoming. Moreover, since the adhesive is expensive, the cost of the cushioning material is increased.

  Accordingly, an object of the present invention is to provide a cushioning material that can exhibit desired cushioning performance while reducing the amount of expensive existing adhesive used, and a method for manufacturing the same.

  The cushion material of the present invention and the method for producing the same are obtained by mixing soft cells (powder) that have been discarded as waste material in the process of obtaining bamboo fiber from bamboo into the cushion material, and molding the cushion material. It will be. That is, it is characterized in that bamboo parenchyma cells, which are waste material, are used as an alternative material for the adhesive.

  According to the cushion material of the present invention and the method for producing the same, bamboo soft cells contain a large amount of starch that is gelatinized by moisture + heating, and they are gelatinized by steam heating at the time of compression molding and have an adhesive action as a binder component. It contributes to. The bamboo soft cells have a very small bulk density (specific gravity) as compared with existing urethane adhesives, and when the bamboo soft cells are mixed, the amount of existing adhesive used can be reduced and the weight can be reduced. At this time, the weight of the cushion material as a whole can be reduced. Furthermore, the bamboo soft cells, which have been wastes so far, can be used as an alternative to the adhesive, thereby making it possible to manufacture cushion materials and reduce product costs.

It is the schematic which shows the manufacturing process of a cushion material. It is the schematic which shows the parenchyma tissue of bamboo. It is a graph which shows the relationship between the mixing rate of a bamboo parenchyma cell, and the adhesive strength of the cushioning material when the compression magnification is 1.5. It is a graph which shows the relationship between the mixing rate of the bamboo parenchyma cell, and the adhesive strength of the cushioning material when the compression ratio is 3.0. It is the schematic which shows the bamboo fibrillator for collect | recovering the soft cells (powder form) which were thrown away as a waste material in the bamboo fiberization process for fiberizing bamboo and obtaining a bamboo fiber. It is a graph which shows the relationship between the rotation speed of the pin roll of a bamboo defibrating machine, and the collection | recovery amount of the soft cell which can be substituted as an adhesive of a cushioning material in the bamboo fiberization process for obtaining bamboo fiber by making bamboo into fiber. .

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may be different from the actual ratios.

  The method for manufacturing a cushion material according to this embodiment includes a step of mixing an adhesive and an alternative material for the adhesive into a piece of the cushion material (mixing step), and putting the mixture obtained in the step into a mold, and steam And a step of compression molding while heating (compression molding step). In this embodiment, plant-based natural material parenchymal cells (attached to bamboo short fibers), which are accompanying materials (conventionally discarded as waste materials) that emerge in the process of fiberizing bamboo as an alternative material for adhesives (Including effective parenchyma cells).

  Referring to FIG. 1, the manufacturing method of the cushion material according to the present embodiment will be outlined. In the mixing step, the openable lid 1a of the mixer 1 is opened and the cushion material fragments 2 and bamboo powder are opened. 3 are introduced into the mixer 1 (including parenchymal cells attached to bamboo short fibers). While mixing the materials 2 and 3 by rotating the mixer 1 (rotating drum), the adhesive (liquid) 4 is introduced from the mixer upper inlet 1b and mixed. By this mixing operation, it is possible to obtain a mixture 5 formed by adhering and applying powdery parenchyma 3 and adhesive 4 to the surface of each piece 2 of the cushion material.

  Here, the mixer 1 is not particularly limited, and any conventionally known mixer / stirrer suitable for the present embodiment can be appropriately used. Depending on the case, you may use what was previously equipped with the temperature control apparatus (means) which can be heated or cooled to such an extent that reaction hardening and gelatinization do not advance. Moreover, you may use what was equipped with the apparatus (means) which can spray water and an adhesive agent moderately during mixing inside apparatus. Further, there is no particular limitation such that an apparatus capable of continuously performing the mixing step may be used so as to be suitable for mass production. Further, the rotational speed of the mixer is not particularly limited as long as it can be uniformly and efficiently mixed.

  Moreover, when using the parenchyma cell attached to the bamboo short fiber, the blending ratio (weight ratio) of the above-mentioned cushion material fragments, short fiber and parenchyma is set to 6-8: 2 to 1: 2-1. Is desirable. By setting the amount within this range, it is possible to reduce the amount of existing adhesive used and reduce the weight, and at this time, it is possible to effectively express the operational effects of the present embodiment, such as the weight reduction of the entire cushioning material. . About the compounding quantity of an adhesive agent, it is desirable from a viewpoint of weight reduction to reduce to about 10-20 wt% of the whole.

  Next, in the compression molding process, the mixture 5 obtained in the above process is put into a mold 8 using a mold bottom 7 having a hole 6 into which steam (water vapor) can be inserted. Thereafter, a steam (heated steam) 10 is inserted from the hole 6 of the mold bottom 7 and is steam-heated. After the compression molding, a desired cushioning material (molded product) 11 can be obtained by removing the press machine 9 and taking out the molded product 11 from the mold 8.

  Here, the hole 6 of the mold bottom 7 is not particularly limited as long as the mixture 5 has a size that does not allow the mixture 5 to spill out and can uniformly insert steam (heated steam) into the mold. In the embodiment shown in FIG. 1, holes having a size of about 1 mm are formed in a lattice pattern at the bottom of the mold at intervals of about 5 cm. However, it is not limited to these. In the present embodiment, an example in which the hole 6 is provided only in the mold bottom 7 is shown, but a similar hole may be provided in the side surface of the mold 8. Further, the size, shape, interval, and arrangement of the holes are not limited to a lattice shape. For example, taking the hole arrangement as an example, in addition to the lattice arrangement, a rhombus arrangement, an arrangement arranged concentrically with the center of the mold bottom 7 as a base point, and the like are optimal depending on the size and shape of the mold. What is necessary is just to select the arrangement | sequence of a hole suitably. The size, shape, and interval of the holes are not limited to those exemplified above as in the case of the arrangement, and those having appropriate sizes, shapes, and intervals can be appropriately used. Furthermore, when a large mold is used, a temperature gradient due to steam heating is formed between the central portion and the peripheral portion. It is desirable to adopt a shape, spacing, and arrangement. These may be obtained by performing a preliminary experiment or the like, and may be obtained using an appropriate calculation model, or may be combined.

  Further, the compression condition varies depending on the cushion performance (elastic modulus, durability, repulsive force, etc.) required depending on the intended use of the molded product (cushion material), and may be appropriately adjusted according to the cushion performance.

  For example, when used for interior materials that require automotive cushioning performance such as seats of seats installed on vehicles and armrests of armrests, the compression ratio is desirably 1.5 to 3 times. Here, the compression ratio means a value obtained by dividing the height of the material (mixture) in the mold before compression by the height after molding (molded product), and the larger the specific gravity of the molded product (cushion material). . When the compression ratio is less than 1.5 times, since the compression of the molded product (cushion material) is small and the molded product has a large expansion / contraction rate, the user may feel uncomfortable. The contact portion between the pieces 2 of the cushion material is small, and the bonding site (region) through the adhesive or parenchyma is also small. For this reason, when the cushion material repeatedly expands and contracts, the load on the binding site is increased, and the durability may be insufficient. On the other hand, if the compression ratio exceeds 3.0, compression of the molded product (cushion material) is large and the molded product becomes a hard molded product with a small expansion / contraction rate. Then you may feel pain. The contact portion between the pieces 2 of the cushion material is large, and the bonding site (region) through the adhesive and parenchyma is also large. Therefore, it is necessary to use a large amount of an adhesive and parenchyma, and there is a possibility that weight reduction becomes difficult.

  When used in interior materials that require automotive cushioning performance such as seats and armrests of seats installed in vehicles, the temperature during compression may be around 100 ° C. This temperature condition is a temperature that can be achieved by steam (heated steam), and is excellent in that no other heating means is required. However, the lower limit of the temperature at the time of compression is different depending on the adhesive used, and is not particularly limited as long as it is higher than the heat curing temperature of the adhesive and higher than the gelatinization temperature of the soft cell. . The upper limit of the temperature at the time of compression varies depending on the adhesive used, and is not particularly limited as long as it is lower than the temperature at which the adhesive is heat-deteriorated and lower than the temperature at which the soft cells are heat-degraded. .

  When used for interior materials that require automotive cushion performance such as seats and armrests of seats installed in vehicles, a compression time of about 2 to 5 minutes is sufficient. What is necessary is just to adjust this compression temperature suitably according to the said temperature conditions and compression magnification. When the compression time is less than 2 minutes, there is a possibility that compression to a sufficient compression ratio has not been achieved, the heat curing reaction of the adhesive has not been completed, or the gelatinization of the soft cells has not been completed. When the compression time exceeds 5 minutes, it is sufficiently molded, and the effect of applying further compression cannot be expected, which is uneconomical. In addition, after compressing to a predetermined compression ratio and finishing compression at the stage where the heat curing reaction of the adhesive and gelatinization of the parenchyma cells are completed, until the gelatinized parenchyma cells are cooled and solidified (the desired adhesive strength is It is desirable that the molded product is not placed in a deformed state until an external load is applied. In addition, dry air is inserted from the hole at the bottom of the mold after compression molding to remove (evaporate) the moisture inside the molded product (cushion material) (those liquefied from the inserted steam vapor) and dry. In order not to impair the performance of the molded product, drying or slow cooling may be appropriately performed.

  The cushion material of the present embodiment is a cushion material formed by mixing and molding a piece of cushion material, an adhesive, and an alternative material for the adhesive, and bamboo soft cells are used as the alternative material for the adhesive. It is characterized by being. In other words, the cushion material of the present embodiment is composed of cushion material fragments, an adhesive, and bamboo soft cells.

  Referring to FIG. 1, the cushion material according to the present embodiment is generally a cushion formed by mixing and molding a cushion material fragment 2, an adhesive 4, and bamboo soft cells 3 as an alternative material of the adhesive. It is a material (molded product) 11. In this cushioning material 11, the adhesive 4 and bamboo soft cells 3 on the surface of the cushion material fragments 2 are compression-molded in a state where the cushioning material fragments 2 are bonded together by reaction hardening and gelatinization by steam heating. It is what has been. In other words, the cushion material 11 of the present embodiment is composed of the cushion material fragments 2, the adhesive 4 that is reactively cured by steam heating during compression molding, and the bamboo soft cells 3 that are gelatinized by steam heating. . And it can be said that it forms by the state with which the fragments 2 of the cushion material were couple | bonded by the adhesive agent 4 which the reaction hardening hardened, and the gelatinized bamboo soft cell 3. FIG.

  The cushion material (molded product) of this embodiment is widely used for various cushion materials including interior materials that require automotive cushion performance such as seats of seats installed on vehicles and armrests of armrests. It can be used. The cushion material 11 includes a cushion material (recycled product) such as a rebonding foam in addition to a new cushion material. From the viewpoint of reusing effective resources and reducing costs, it is preferable to use cushion materials (recycled products) such as rebonding foam as cushion materials (molded products).

  Hereinafter, each constituent requirement of this embodiment will be described in detail.

[Debris of cushion material]
The pieces 2 of the cushion material that can be used in the present embodiment are not particularly limited, and conventionally known pieces of various cushion materials can be applied. In particular, for a sheet having a large curvature, the mass of cushion material is cut into smaller pieces than a normal cushion material (for example, a mass of polyurethane foam). A cushion material (molded article) 11 in which is compressed and bonded with an adhesive is suitable. Such a piece 2 of the cushion material is preferably a piece of urethane (for example, polyurethane foam), and more preferably a chip-like scrap of urethane. There is no restriction | limiting in particular as the urethane debris 2 used for the cushion material 11, For example, the fragment of a polyurethane foam etc. can be used. Polyurethane foams are broadly classified into soft foams and rigid foams. They are classified into ether type or ester type depending on the type of polyol. The There is no difference in performance between the two types of rigid foam. Since the soft (flexible) ether type is excellent in elasticity and has a variety of raw materials, urethane fragments 2 having a wide range of physical properties can be selectively produced at a relatively low cost. On the other hand, the soft (flexible) ester type has excellent mechanical properties such as compression / elongation, high strength, low wear, heat / oil resistance / weather resistance, high coloration, and variation in cell size. There is a feature that works. However, the piece 2 of the cushion material is not limited to the piece of urethane (for example, polyurethane foam), and a piece of cushion material made from an optimal raw material may be used as appropriate according to the intended use. it can. In addition to the new cushion material fragments 2 manufactured from the above-mentioned raw materials, the cushion material fragments 2 may be recycled recycled cushion materials or cushion materials such as cut ends after the product is die cut during the manufacturing process. It shall include the piece 2 of the cushion material manufactured using. From the viewpoint of reuse of effective resources and cost reduction, the pieces of cushion material 2 may be recycled cushion materials such as reclaimed cushion materials or cut-off portions after products are die cut during the manufacturing process. Good.

  Further, regarding the size of the pieces 2 of the cushion material, for example, a mass of cushion material (polyurethane foam, etc.) that has been appropriately cut and crushed according to the intended use may be used. Is not to be done. Further, the shape of the piece 2 of the cushion material is not particularly limited. For example, it can be obtained by appropriately cutting a lump cushion material (polyurethane foam, etc.) into an optimal size according to the application. It is desirable to use the chip-shaped fragments as they are. This is because the entire mass of cushion material can be used as a piece of cushion material without adding an extra step.

  As a blending amount of the fragment 2 of the cushion material in the cushion material 11, it can be blended up to about 80 to 90 wt% of the entire cushion material. Thereby, compared with the existing cushion material which does not use the alternative material of an adhesive agent, the weight reduction of about 5-10 wt% can be achieved also as the cushion material whole. Moreover, since the compounding ratio of the fragment 2 of the cushion material can be increased as compared with the conventional case, in other words, the amount of the adhesive having no cushioning property can be reduced, the cushion performance can be improved as compared with the conventional case. However, the amount of the cushion material fragments 2 in the cushion material 11 is not limited to the range specified above. That is, even if the amount of the cushioning material is about 60 to 80 wt%, which is about the same as the conventional amount, the effect of the present invention can be fully expressed by blending an appropriate amount of the substitute material for the adhesive. It is.

[adhesive]
The adhesive 4 that can be used in the present embodiment is not particularly limited, and various adhesives used for the existing cushion material 11 can be appropriately used. That is, also in this embodiment, since the steam heating (including high-pressure steam) (around 100 ° C.) is performed in the compression molding process as described above, the adhesive can be reactively cured (heat-cured) under the thermal conditions. If it is. For example, when the piece 2 of the cushion material uses a piece of urethane, preferably, polyurethane such as urethane prepolymer containing 1 to 10% unreacted isocyanate group at the molecular end as described in Patent Document 1. Although it is a system adhesive, it is not restrict | limited to these at all.

  The form of the adhesive 4 is not particularly limited. Preferably, a liquid adhesive is desirable at the time of mixing so that it can be applied to the surface of the debris 2 of the cushion material (including soft cells 3 attached to the surface of the debris 2 of the cushion material) in the mixing step. However, it may be powdery as long as it can adhere to the surface of the debris 2 of the cushion material together with the powdery parenchyma 3 during mixing. Even in the case of a powdery adhesive at the time of mixing, it is necessary to carry out reaction curing (heat curing) by steam heating (around 100 ° C.) in the compression molding process.

  As the blending amount of the adhesive 4 occupying the cushion material 11, the amount of existing adhesive used can be reduced by about 15 to 30 wt%, and the weight can be reduced. Here, the amount of existing adhesive used is about 20 to 40 wt% of the entire cushion material. Therefore, the blending amount of the adhesive 4 in the cushion material 11 in the present embodiment is about 14 to 34 wt% of the entire cushion material. Thereby, compared with the existing cushion material which does not use the alternative material of the adhesive agent 4, the weight reduction of about 5-10 wt% as a whole cushion material can be achieved. Moreover, since the amount of adhesive having no cushioning can be reduced as compared with the conventional case, the cushioning performance can be improved as compared with the conventional case. However, the amount of the adhesive 4 in the cushion material 11 is not limited to the range specified above. That is, even if it reduces to about 10-20 wt% of the whole cushioning material, the effect of this invention can fully be expressed by mix | blending an appropriate amount of the substitute material of the adhesive agent 4. FIG.

[Bamboo soft cells, which are alternative materials for adhesives]
As an alternative material for the adhesive 4 that can be used in the present embodiment, bamboo soft cells 3 may be used, and the production history is not particularly limited. The use of powdered parenchyma cells (including parenchyma cells attached to bamboo short fibers) that are usually discarded as waste material in the process of making bamboo into fibers reduces the production of cushion materials and product costs. Is desirable in that it can be achieved.

  As shown in FIG. 2, the bamboo parenchyma cells 3 contain a large amount of starch that is gelatinized by moisture and heating, and when they are steam-heated in the compression molding process, they can be gelatinized and contribute to the adhesive action. It can be done.

  The form of the bamboo parenchyma 3 is not particularly limited. It is desirable to use powdered parenchyma at the time of mixing so that it can adhere to the surface of the debris 2 of the cushion material (including parenchy cells 3 adhering to the surface of the debris 2 of the cushion material) in the mixing step. However, when the powdered parenchyma 3 is very light during mixing and is difficult to mix evenly when mixed into the pieces 2 of the cushioning material, it is used after the parenchyma 3 is previously sprayed with water and moistened. May be.

  From the viewpoint of workability at the time of mixing, it is preferable to use parenchyma cells 3 attached to bamboo short fibers as an alternative material for adhesive 4. By making the soft cells (powder) 3 attached to the short fibers (cotton), it becomes close to the specific gravity of the pieces 2 of the cushion material, and when mixed into the pieces 2 of the cushion material, it becomes easy to mix evenly. . Furthermore, because the bamboo short fibers are cotton-like, they can be used as a partial replacement for the pieces 2 of the cushion material, and the exhaustible resources can be reduced. The parenchyma cells 3 attached to the bamboo short fibers are in a state where the short fibers and the parenchyma cells are integrated, and in the mixing process of the manufacturing method described below, the parenchyma cells 3 are mixed with the fragments of the cushion material. It can also be said that the parenchyma cells are attached to such a degree that they do not peel from the short fibers.

  As shown in FIGS. 3 and 4, the blending amount of bamboo soft cells (excluding bamboo short fibers) in the cushion material 11 varies depending on the compression ratio in the compression molding process. For example, referring to FIG. 3, when the compression ratio is 1.5 times, if the mixing ratio (blending amount) of parenchymal cells exceeds about 0 wt% to about 10 wt%, the existing adhesive alone is used. Adhesive strength comparable to that can be expressed. When the parenchymal cells 3 having weaker adhesive strength than the existing adhesive are contained in excess of about 10 wt%, the ratio of the existing adhesive is relatively lowered. Therefore, when the compression ratio is as low as 1.5, it can be said that the contact portion between the pieces of the cushion material is small and close to point contact, and it is difficult to obtain sufficient adhesive strength. On the other hand, referring to FIG. 4, when the compression ratio is 3.0 times, if the mixing ratio (blending amount) of parenchyma exceeds about 0 wt% to about 20 wt%, the existing adhesive alone is used. Adhesive strength comparable to that can be expressed. When the compression ratio is as high as 3 times, the contact portion between the pieces of the cushion material is large and in a surface contact state, and sufficient adhesive strength can be secured until the ratio of the existing adhesive exceeds about 20 wt%. I understand. On the other hand, from the viewpoint of reducing the amount of existing adhesive used and reducing the weight, it can be said that the greater the amount of parenchyma cells, the better. From the above, the blend amount of bamboo soft cells (excluding bamboo short fibers) in the cushion material 11 varies depending on the compression ratio in the compression molding process, but is preferably about 5 to 20 wt% or less of the entire cushion material. Is preferably about 10 to 20 wt%. When the soft cells 3 attached to the bamboo short fibers are used, the amount of each of the bamboo soft cells and the short fibers in the cushion material 11 varies depending on the compression ratio in the compression molding process. A range of about 5 to 20 wt% or less, preferably about 10 to 20 wt% of the entire material is desirable. Thereby, compared with the existing cushion material which does not use the substitute material of the adhesive agent 4, the weight reduction of about 3-10 wt% as a whole cushion material can be achieved, Preferably it is about 5-10 wt%. Moreover, since the amount of adhesive having no cushioning can be reduced as compared with the conventional case, the cushioning performance can be improved as compared with the conventional case. However, the blending amount of the soft cells and the short fibers in the cushion material 11 is not limited to the range specified above, and is as long as it is a range in which the effects of the present invention can be sufficiently expressed. It may be out of range.

  In the present embodiment, parenchymal cells (including parenchymal cells attached to bamboo short fibers) are defibrated in a bamboo fiberization process in which bamboo fibers are obtained by pulverizing bamboo using a defibrating machine. By doing so, the thing separated and collect | recovered from a bamboo fiber can be used. This is because the soft cells (powder) can be taken out (created) in a state of being attached to short fibers (cotton) having a small bulk specific gravity without adding a process after the bamboo fiberizing process.

  When using the parenchymal cells 3 attached to the bamboo short fibers, the mixture ratio of the parenchymal cells and the short fibers is about 1: 1 to 1.3, preferably 1: 1 to 1.2 by weight. It is a range. This is because the above-described effects can be effectively expressed when the soft cells 3 attached to the bamboo short fibers are used. When the ratio of the parenchyma cells 22 having adhesiveness in the mixture of the parenchyma cells 22 + short fibers 21S is smaller than the range specified above, the blending ratio of the existing adhesive must be relatively increased, There is a possibility that it is not suitable as a substitute material for the adhesive 4 of the cushion material 11. On the other hand, recovering the ratio of the parenchyma cells 22 having adhesiveness in the mixture of parenchyma cells 22 + short fibers 21S to be larger than the range specified above means that the parenchyma cells 22 are attached to the short fibers 21S. Since these are collected, in order to separate them, it is necessary to add a process for separating both after the bamboo fiberizing process, which may lead to an increase in cost.

  Referring to FIG. 5, in the bamboo fiberizing process for recovering parenchymal cells (including parenchymal cells attached to bamboo short fibers), a defibrating machine 111 for fiberizing bamboo 20 is arranged. The defibrator 111 has a conveyor 112 for supplying bamboo 20, a feed roll 113, a pin roll 114 provided with a large number of teeth, and a dust collector 115. Bamboo 20 that has been softened through cutting, delignification treatment, and pressing is sent to the right in the figure by conveyor 112 and feed roll 113. The pin roll 114 rotates faster than the feed roll 113 and is defibrated by scratching the bamboo 20 with a number of teeth softened. When the bamboo 20 is defibrated, bamboo fibers 21 and parenchyma cells 22 are obtained. The obtained bamboo fibers 21 are long fibers 21L (for example, the average fiber length is 50 mm or more) and short fibers 21S (for example, the average fiber length). Is less than 50 mm). The soft cells 22 are cotton-like or powdery, and the short fibers 21S are cotton-like. The parenchyma 22 and the short fibers 21S have a lower specific gravity than the long fibers 21L. For this reason, most of the parenchyma cells 22 and the short fibers 21S can be collected by the dust collector 115. The long fibers 21L are blown off with the hooking operation of the pin roll 114. As described above, the parenchyma cells 22 and the short fibers 21S can be sorted into the first container 116 and the long fibers 21L can be sorted and collected into the second container 117 depending on the difference in specific gravity. The ratio of the soft cells 22 and the short fibers 21S is about 10 to 20% per unit weight after defibration.

  By changing the number of rotations of the pin roll 114, the size of the teeth, and the installation density, the ratio of the short fibers 21S and the long fibers 21L, the diameter of the bamboo fibers 21, the average fiber length, and the like can be changed. Fiber 21 can be obtained. For example, when the rotational speed of the pin roll 114 is sufficiently high with respect to the feed roll 113, a part of the softened bamboo 20 pressed by the feed roll 113 is defibrated so that the pin roll 114 is torn off. Thereby, the ratio of the short fibers 21S can be relatively increased.

  From this point of view, it is desirable that the pin roll 114 of the defibrator 111 is separated and collected from the long fibers 21L by defibration in the range of the rotational speed of 400 to 1000 rpm. In the bamboo fiberizing process, when the pin roll 114 is defibrated within the range of 400 to 1000 rpm, the soft cells (powder) 22 are attached to the cotton-like short fibers 21S having a small bulk specific gravity and a fiber length of less than 50 mm. This is because it can be separated from the long fibers 21L and collected in the first container 116 by the dust collector 115. Furthermore, the parenchymal cells 22 attached to the short fibers 21S obtained by defibration in the range of the rotation speed of the pin roll 114 within the range of 400 to 1000 rpm, as shown in FIG. 6, are a mixing ratio of the parenchymal cells 22 and the short fibers 21S. Is excellent in that it can be recovered within the range specified above. On the other hand, when the pin roll 114 has a rotation speed of less than 400 rpm, the parenchyma 22 is not sufficiently separated from the long fibers 21L because the speed is low. When the pin roll 114 has a rotation speed exceeding 1000 rpm, the long fibers 21L are torn to form short fibers 21S, and many short fibers 21S are produced. As a result, the ratio of the soft cells 22 having adhesiveness in the mixture of the soft cells 22 and the short fibers 21S becomes small, and the mixing ratio of the existing adhesive must be relatively increased. This is because it may not be suitable for the alternative material.

As described above, according to the cushion material 11 of the present embodiment, when soft cells 3 having a very small bulk density (specific gravity) as compared with an existing urethane adhesive or the like are mixed as an alternative material to the adhesive 4. The amount of existing adhesive can be reduced and the weight can be reduced. At this time, the weight of the cushion material as a whole can be reduced. Specifically, as described above, soft cells 3 are mixed in an amount of about 5 to 20 wt%, preferably about 10 to 20 wt% of the entire cushioning material, so that the amount of existing adhesive used is about 8 to 30 wt%, preferably The weight can be reduced by about 15-30 wt%. At this time, the weight of the cushion material as a whole can be reduced by about 3 to 10 wt%, preferably about 5 to 10 wt%, while maintaining the same adhesive strength as that of the existing adhesive alone. Furthermore, the bamboo soft cells, which have been wastes so far, can be used as an alternative to the adhesive, thereby making it possible to manufacture cushion materials and reduce product costs. In addition, parenchyma cells are an accessory that comes out in the process of fiberizing bamboo, and those that have been discarded as waste can be used effectively. Further, since the parenchymal cells are plant-based natural materials, when the used cushioning material 11 is discarded and incinerated, the amount of CO ₂ emitted by the parenchymal cells as biomass is counted as zero. Therefore, it can be an extremely excellent product for the global environment. In addition, the cushion material of the present invention has a soft texture, does not feel coarse, has a small compression hysteresis loss, and is very elastic, and has the same or better cushion performance as existing cushion materials. It is done.

  In addition, by using soft cells attached to bamboo short fibers as the substitute material for the adhesive, it becomes close to the specific gravity of the fragment 2 of the cushion material and is mixed into the fragment 2 of the cushion material. It becomes easy to mix evenly. Moreover, since the short fiber 21S is cotton-like, it becomes a partial replacement for the fragment 2 of the cushion material, and the depletion resource can be reduced. In addition, the specific gravity of the fragment 2 of the cushion material is usually about 0.04 to 0.1, and the specific gravity (apparent density) of the existing adhesive is about 1 (about the same as water). Moreover, if the compression ratio is 1.5 to 3 times, the specific gravity of the molded product is about 1 to 2 times, and the bulk specific gravity is small, and it can be said that weight reduction can be achieved.

  Furthermore, the parenchyma cell 22 is separated and collected from the bamboo fiber 21 by defibration of the bamboo 20 using the defibrator 111, so that the parenchyma cell is not added after the fiberizing step. It is possible to create a state in which 22 is attached to the short fiber 21S having a small bulk specific gravity. As a result, it becomes close to the specific gravity of the pieces 2 of the cushion material, and when mixed into the pieces 2 of the cushion material, it becomes easy to mix evenly, and a uniform molded product (cushion material) 11 can be obtained.

  Furthermore, the parenchyma cell 22 is separated and collected from the bamboo fiber 21 by defibration in the range of 400 to 1000 rpm of the rotation speed of the pin roll 114 of the defibrator 111, so that the parenchyma cell 22 has a bulk specific gravity. It can be efficiently separated and recovered from the long fibers 21L in a state of adhering to the cotton-like short fibers 21S having a small fiber length of 50 mm or less.

  According to the manufacturing method of the cushion material 11 of the present embodiment, by using the bamboo soft cells 3 as an alternative material of the adhesive 4, using the existing cushion material manufacturing apparatus and process shown in FIG. The amount of existing adhesive can be reduced and the weight can be reduced. At this time, the weight of the cushion material as a whole can be reduced. Furthermore, the bamboo soft cells, which have been wastes so far, can be used as an alternative to the adhesive, thereby making it possible to manufacture cushion materials and reduce product costs. Further, since the long fibers 21L separated and collected from the bamboo fibers 21 are used for various purposes as in the prior art, there is no waste.

1 mixer,
1a lid,
1b Adhesive inlet,
2 Debris of cushion material,
3 parenchyma cells (including parenchyma cells attached to bamboo short fibers),
4 Adhesive,
5 mixture,
6 holes,
7 mold bottom,
8 formwork,
9 Embossing machine,
10 Steam (water vapor),
11 Cushion material (molded product),
20 bamboo,
21 bamboo fiber,
21L long fiber,
21S short fiber,
22 soft cells,
111 defibrator,
112 conveyor,
113 feed roll,
114 pin roll,
115 dust collector,
116 first container,
117 Second container.

Claims (8)

A cushion material formed by mixing and molding a piece of cushion material, an adhesive, and an alternative material for the adhesive,
A cushion material, wherein bamboo soft cells are used as an alternative to the adhesive.   The cushion material according to claim 1, wherein the soft cell attached to bamboo short fibers is used as an alternative material for the adhesive.   The cushion material according to claim 2, wherein the soft cells are separated and recovered from bamboo fibers by defibrating bamboo using a defibrating machine.   The cushion material according to claim 3, wherein the soft cells are separated and collected from bamboo fibers by defibration in a range of rotation speed of a pin roll of the defibrator of 400 to 1000 rpm.   The cushion material according to claim 1, wherein the pieces of the cushion material are urethane pieces.   6. The cushion material according to claim 1, wherein the pieces of the cushion material are urethane chip-shaped scraps. Mixing an adhesive and a substitute material for the adhesive into a piece of cushion material;
In the method for producing a cushioning material, the mixture obtained in the step is put into a mold and compression-molded with steam heating.
A method for producing a cushioning material, wherein bamboo soft cells are used as an alternative to the adhesive.   The cushion material according to claim 7, wherein the soft cells are separated and collected from the bamboo fibers in a state of being attached to the short fibers of the bamboo by defibrating the bamboo using a defibrating machine. Manufacturing method.