JP2016050365A - Fiber compact with cushioning property and product made of fiber compact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber compact that is highly resistant to repeated compression and has high flexibility and cushioning property.SOLUTION: A fiber layer 3 is made by opening a continuous fiber bundle that has crimps and extends in one direction. A fiber compact 1 has a structure in which the continuous fiber is folded in the extending direction of the continuous fiber so that the rib 2 repeatedly appears on the surface of the fiber layer 3. The fiber compact has either of two forms in which the rib 2 is compressed to be flat in a thickness direction 4 of the fiber compact 1 on the surface of the fiber compact 1, or a continuous curve surface is formed from the fiber layer 3, which forms the rib 2 and extends from both sides of the rib 2 in the thickness direction 4 of the fiber compact 1. The fiber layers 3 of the ribs, which extend in the thickness direction 4 of the fiber compact 1 and lie next to each other, firmly stick to each other in the thickness direction 4 of the fiber compact 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fiber molded body having cushioning properties and a product using the same.

The fiber molded body used for the cushion material is usually a needle punched nonwoven fabric obtained by laminating a card web with a cross layer or the like and obtained by a needle punch method. The needle punched non-woven fabric is a nonwoven fabric obtained by squeezing while entwining fibers in a web with a plurality of needles. Needle punched nonwoven fabrics obtained by this method generally have a low degree of freedom of fibers in the nonwoven fabric, less voids, and tend to have a lower thickness, which inevitably decreases cushioning, heat retention, and sound insulation. .
Examples of the fiber molded body obtained by other production methods include a non-woven fabric obtained by folding a short fiber into a web by a card method (see, for example, Patent Document 1). Here, “folding” means that the web is folded in the MD direction of the web by pleating or the like. However, although the nonwoven fabric obtained by this method is excellent in cushioning properties, it is composed of short fibers, so that when it is repeatedly compressed, fuzz and lint are generated, and the durability of repeated compression is inferior. is there.

JP 2007-308831 A

  Then, the subject of this invention is providing the fiber molded object which is excellent in durability of repeated compression, and is excellent in a softness | flexibility, cushioning property, and its durability (durable cushioning property).

  The inventors of the present invention have made extensive studies in order to solve the above problems. As a result, by using a fiber layer formed by opening a bundle of continuous fibers having crimps and extending in one direction, it is excellent in durability of repeated compression by forming a fiber molded body of a specific structure, Furthermore, it discovered that the fiber molding excellent in cushioning property and a softness | flexibility was obtained, and came to complete this invention based on this knowledge.

The present invention has the following configuration.
[1] The fiber layer 3 formed by opening a bundle of continuous fibers having crimps and extending in one direction is in a direction in which the continuous fibers extend so that the wrinkles 2 repeatedly appear on the surface of the fiber layer 3. A fiber molded body 1 having a folded structure, and the fiber molded body forms, on the surface of the fiber molded body 1, a ridge 2 having a shape compressed and flattened in the thickness direction 4 of the fiber molded body 1. Or the fiber molded body forms a ridge 2 and forms a continuous curved surface with a fiber layer 3 extending from both sides of the ridge 2 in the thickness direction 4 of the fiber molded body 1, and forms a ridge to form a fiber. The fiber molded body 1 in which the adjacent fiber layers 3 extending in the thickness direction 4 of the molded body 1 are in close contact with each other in the thickness direction 4 of the fiber molded body 1.
[2] The continuous fiber is a heat-fusible continuous fiber, and the adjacent fiber layers are joined by heat-sealing of the heat-fusible continuous fiber of the fiber layer 3. The fiber molded body 1 according to [1], which is in close contact with each other in the thickness direction 4.
[3] At least a part of the heat-fusible continuous fibers constituting the fiber layer 3 in close contact with each other is entangled in at least one of the fiber layers of the cocoon, and the inside of the fiber layer of the cocoon The fiber molded body 1 according to the above [2], wherein the heat-fusible continuous fiber constituting the fiber layer 3 and the entangled heat-fusible continuous fiber are joined by heat-sealing. .
[4] A fiber molded body 1 in which a stamp pattern is further formed on the surface side of the fiber molded body 1 according to any one of [1] to [3] having the ridge 2.
[5] The fiber molded body 1 according to any one of [1] to [4], wherein the continuous fiber is a sheath-core type composite continuous fiber having polyester as a core and polyethylene as a sheath.
[6] A product obtained using the fiber molded body 1 according to any one of [1] to [5].

  The fiber molded body of the present invention is excellent in flexibility and cushioning properties. In addition, even when repeated compression is performed, the amount of lint generated is small and the fuzz resistance is good (the fuzz is less likely to occur). Moreover, since the fiber molded body of the present invention has a folded structure, it has high vertical resilience and good texture. Moreover, since there are many voids in the fiber molded body, it is excellent in heat retention and sound insulation.

The schematic diagram which looked at the fiber molded object of this invention from the cross section The perspective view of the fiber molded object of this invention

<Fabric molding>
The fiber molded body of the present invention has a fiber layer formed by opening a bundle of continuous fibers having crimps and extending in one direction, and the continuous fibers extend so that wrinkles repeatedly appear on the surface of the fiber layer. It has a structure folded in a certain direction.
The fiber molded body forms a ridge having a shape that is compressed and flattened in the thickness direction of the fiber molded body on the surface of the fiber molded body, or the fiber molded body forms a ridge and fiber molded from both sides of the ridge. A continuous curved surface is formed by fiber layers extending in the thickness direction of the body, and adjacent fiber layers of wrinkles that form wrinkles and extend in the thickness direction of the fiber molded body are in close contact with each other in the thickness direction of the fiber molded body. ing.
The term “発 明” as used in the present invention refers to a crop that can be seen in a field or the like when viewed from a direction perpendicular to the thickness direction of the fiber molded body and from the direction in which the adhesion state and curved surface of the fiber layer can be observed. A structure in which a certain state of height is continued in the horizontal direction, like a cocoon for cultivating rice.

<Fiber layer>
The fiber layer used in the present invention is formed by opening a bundle of continuous fibers having crimps and extending in one direction. By using a bundle of continuous fibers and having a structure that is folded in the direction in which the continuous fibers extend so that wrinkles appear repeatedly on the surface of the fiber layer, the resulting fiber molded body is repeatedly used for compression. Even in such a case, it can be preferably used as a cushioning material because it is excellent in durability of repeated compression such that fuzz and lint hardly occur.

  The fiber layer formed by opening a bundle of continuous fibers having crimps and extending in one direction is not particularly limited, but is manufactured by adjusting the continuous fibers to be aligned in one direction by a spunbond method. A fiber layer obtained by a known method, such as a fiber layer or a fiber layer produced by opening a continuous fiber, in particular, a tow extending in one direction, by a tow opening method can be used. . In view of cushioning properties and bulkiness, it is preferable to use a fiber layer obtained by a toe opening method.

<Continuous fiber>
Although the continuous fiber used for this invention is not specifically limited, From the point of durability of repeated compression, it is preferable to have heat-sealability, and it is especially preferable that it is a heat-sealable composite continuous fiber.

<Heat-fusion composite continuous fiber>
The heat-fusible composite continuous fiber is preferably a composite continuous fiber composed of a low melting point component and a high melting point component. Examples of the combination of low melting point component / high melting point component include, but are not limited to, polyethylene / polypropylene, polypropylene copolymer / polypropylene homopolymer, polyethylene / polyethylene terephthalate and the like. The polyethylene used in the present invention is a polyethylene homopolymer, a copolymer of ethylene and propylene or another olefin, a copolymer of ethylene and another copolymer component, or the like. The polypropylene used in the present invention is a polypropylene homopolymer, a copolymer of propylene and ethylene or another olefin, a copolymer of propylene and other components, or the like. Examples of the polyester used in the present invention include polyethylene terephthalate, polybutylene terephthalate, and copolymers thereof. In particular, a heat-sealable composite continuous fiber composed of a combination of polyethylene / polyethylene terephthalate is preferable because it takes advantage of the rigidity that is the resin characteristic of polyethylene terephthalate and the final molded product has excellent cushioning properties.

  Examples of the composite form of the heat-fusible composite continuous fiber include a sheath core type and a parallel type. In the case of a sheath-core type composite continuous fiber, it is generally preferable that a low melting point component is arranged in the sheath component in order to exhibit thermal adhesiveness. Examples of the sheath-core type composite continuous fiber include a concentric sheath-core type composite continuous fiber and an eccentric sheath-core type composite continuous fiber. In the present invention, from the viewpoint of cushioning properties, an eccentric sheath-core type composite continuous fiber that easily causes three-dimensional crimps is preferable.

  When the continuous fiber is a heat-fusible composite continuous fiber, the ratio of the low melting point component and the high melting point component is preferably in the range of 30/70 to 70/30 on a volume basis, and is 40/60 to 60/40. A range is further preferred. If the ratio of the low melting point component is 30% by volume or more, when forming a fiber molded body such as a mat, the resulting mat has good adhesion, so that even if it is compressed, the heat-bonding part is present. It has good cushioning properties without breaking. When the ratio of the high melting point component is 30% by volume or more, the low melting point component contributing to adhesion is small, so that the degree of freedom of the fiber is not relatively lowered even after heat bonding. It is preferable because it is excellent in softness (soft) and maintains cushioning properties.

A bundle of continuous fibers is opened (also referred to as “widening”) by a tow opening method to form a fiber layer. Opening is an operation in which continuous fibers are separated from each other in a bundle of continuous fibers (a bundle formed by converging continuous fibers), and the continuous fibers exist individually. Thereby, the bundle of continuous fibers is broken into individual fibers, and the width of the bundle increases to form a fiber layer.
In the opening of a bundle of continuous fibers, the fiber opening effect by the wins roll, the speed ratio between the rolls, and the tension and relaxation by the Z bar (swinging tension bar) are appropriately given to the fiber bundle. , Can be widened uniformly. When giving a tension state to a fiber bundle, it is important not to give an excessive tension to the extent that the crimp of the widened fiber bundle can be extended.

  As the crimp of the bundle of continuous fibers, an actual crimp, a latent crimp, or a combination of an actual crimp and a latent crimp can be used. As the actual crimp, two-dimensional crimps such as a so-called zigzag type of mountain / valley shape, and three-dimensional crimps such as a coil type and a spiral type can be used. It is preferable to be a contraction. The number of crimps of the continuous fibers in the fiber molded body is preferably in the range of 5-25 peaks / 2.54 cm, and more preferably 10-20 peaks / 2. It is preferably 54 cm.

  The bundle of continuous fibers preferably has an actual crimp, and the number of crimps is preferably 8 to 70/25 mm, more preferably 9 to 65/25 mm, and 10 to 50 More preferably, it is / 25 mm. If the number of crimps is 8 peaks / 25 mm or more, the convergence of the tow is good, and when the tow is pulled up, the fiber bundle does not cause excessive vertical cracking, and high-speed fiber opening becomes easy. Moreover, if it is 70 ridges / 25 mm or less, excessive entanglement and densification between continuous fibers hardly occur, and high-speed fiber opening is also easy.

  When the bundle of continuous fibers used for the production of the fiber molded body has a latent crimp due to an eccentric sheath core type composite structure, etc. along with the actual crimp, by the tension applied in the fiber opening process, Due to the difference in stress strain received between the composite structure and each composite component, latent crimps appear (appear). By heating the fiber layer obtained by opening the fiber bundle in a subsequent process, the latent shrinkage is further reduced by utilizing the difference in heat shrinkability between the composite structure of the fiber and each composite component. It may be expressed (emerged).

  When the continuous fiber in the fiber molded body has latent crimps, it is possible to express a crimped shape such as a spiral type that is a three-dimensional crimp by manifesting it, so that cushioning properties and bulkiness Is preferable. At this time, two-dimensional crimps such as a zigzag type may remain at a rate lower than the majority of continuous fibers.

  The single yarn fineness of the continuous fiber is preferably 0.5 to 100 dtex. If the single yarn fineness is 0.5 dtex or more, it is difficult to break single yarn or fluff at the time of opening, and it is possible to open at high speed. Moreover, if it is 100 dtex or less, the convergence property of tow | toe is good and opening workability | operativity becomes favorable, Therefore High-speed opening is possible and the expansion | deployment to various uses is attained.

  The total fineness (total fineness) of the fiber bundle is preferably 10,000 to 500,000 dtex, and more preferably 30,000 to 200,000 dtex. If it is 10,000 dtex or more, the cushioning property by fiber density can be maintained, and if it is 500,000 dtex or less, the widening property is good.

The basis weight of the fiber layer obtained by widening the fiber bundle is preferably 10 to 150 g / cm ² , more preferably 20 to 100 g / cm ² . In particular, in the case of a low basis weight, the folding distance in the folded structure is shortened, the ridges having a low height are present at a high density, and the wall surfaces of adjacent ridges are strongly compressed and closely adhered to each other. On the other hand, when a fiber layer having a high basis weight is used, the folded distance in the folding structure becomes long and the width of the folds widens. In the case of having the former structure, the fiber molded body is hard and strong. In the latter case, voids remain in the fiber layer, so that the fiber molded body is soft, and the structure is expected to be excellent in heat retention and sound insulation. By changing the basis weight within the above range, a cushioning material suitable for the application can be obtained.

The fiber layer obtained by opening (broadening) a bundle of continuous fibers having crimps and extending in one direction used in the present invention has the continuous fibers constituting the fiber layer joined together. Preferably not. For example, it is preferable that a plurality of fusion wires in a direction orthogonal to the length direction of the continuous fibers are not partially joined and integrated (nonwoven fabric).
A fiber layer in which continuous fibers extending in one direction are not joined to each other is folded in a direction in which continuous fibers extend so that wrinkles repeatedly appear on the surface of the fiber layer, and a fiber layer constituting adjacent wrinkles If it is configured to be in close contact with each other, continuous fibers are not joined to each other, and therefore, a state is formed in which a part of the fibers of the fiber layer forming the adjacent wrinkle is entangled (biting) into the fiber layer forming the wrinkle. easy. When heated in this state, the thermal adhesion between the fiber layers constituting both sides becomes stronger than the case where the thermal adhesion is performed only at the contact points of the fiber axes only at the contact interface between the two fiber layers. . Thereby, durability of repeated compression can be enhanced.

<Method for producing fiber molded body>
As a method for producing a fiber molded body having a structure in which a fold is repeatedly formed using a fiber layer in which a bundle of continuous fibers extending in one direction is opened (widened), Examples thereof include a method of pushing a fiber layer into a fin box to form a folded structure, and a method of forming a folded structure using pleating.

The following method can be exemplified as a method of pushing the fiber layer into the staffin box to form a folded structure.
1) The fiber layer is pushed into a box having a structure in which the opening area decreases from the inlet toward the outlet so that the fiber layer is hardly discharged on the outlet side. The fiber layer accumulates in the box and becomes folded.
2) Further, by continuing to push the fiber layer into the box from the inlet side, the folded fiber layer is discharged from the outlet side. A folded structure is given to the discharged fiber layer.
3) Next, in order to make the fiber layer into a fiber molded body, the fiber layers in close contact with each other are joined. For example, in the case where a heat-fusible continuous fiber is used as the continuous fiber, the bonding method uses, for example, a hot-air circulating suction dryer, and heat-bonding the heat-fusible continuous fiber with hot air to adhere to each other. What is necessary is just to join the fiber layers which are carrying out. As the heat-fusible continuous fiber, a heat-fusible composite continuous fiber can be preferably used, and it is bonded by hot air in a temperature range above the melting point of the low-melting component and below the melting point of the high-melting component. Molded.
What is necessary is just to adjust the height of the folded fiber layer with the volume in the box to be used. For example, the volume in the box can be changed by fixing the inlet side of the upper surface of the box and lowering the outlet side. At this time, when the volume is reduced, the folding structure can be reduced, and conversely, when the volume is increased, the folding structure can be enlarged. By this manufacturing method, it is possible to efficiently obtain a fiber molded body in which the adjacent fiber layers of the ridges extending in the thickness direction of the fiber molded body are in close contact with each other in the thickness direction of the fiber molded body. Therefore, it is preferable.
Examples of other methods for producing a fiber molded body include pleating. The manufacturing method of a fiber molded object is not limited to these.

By the above method, generally, a fiber molded body in which the ridge forms a continuous curved surface with fiber layers extending in the thickness direction of the fiber molded body from both sides of the ridge can be suitably obtained. In addition, even if the fiber molded body thus obtained is pressed with a flat plate or the like toward both sides in the thickness direction, the ridges are processed so as to have a shape compressed and flattened in the thickness direction of the fiber molded body. Good.
Moreover, you may shape various stamp patterns on the surface side which has the wrinkles of the fiber molded object obtained in this way. The stamp pattern can be obtained by a method in which a mold or the like on which such a pattern is stamped is pressed against the surface side having the ridges of the molded body while being heated as necessary.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, the scope of the present invention is not limited to these.

  The performance of the fiber molded body of the present invention was performed by the following method.

<Cushioning evaluation method>
The cushioning properties were evaluated by 10 panelists according to the following evaluation criteria.
A: The number of people who felt resilience was 8 or more.
○: The number of people who felt repulsiveness is 5 or more and 7 or less.
X: The number of persons who felt that there was resilience is 4 or less.
In this evaluation method, it was evaluated that the molded product that was evaluated as ○ or ◎ had excellent cushioning properties.

<Flexibility evaluation method>
Ten panelists evaluated the flexibility according to the following evaluation criteria.
A: The number of people who felt flexible was 8 or more.
○: The number of people who felt flexible was 5 or more and 7 or less.
X: The number of people who felt flexible was 4 or less.
In this evaluation method, it was evaluated that the fiber molded body evaluated as ○ or ◎ had excellent flexibility.

<Method for evaluating durability of repeated compression>
Based on the following evaluation criteria, the fiber molded body was cut into 100 mm × 100 mm, and was compressed repeatedly 10 times at a pressure of 3 kgf / cm ² (29.4 Pa) using a compressor. Evaluation was performed. For the evaluation, ten panelists who evaluated the flexibility were appointed.
(Double-circle): The number of people evaluated that there is little or no amount of fluff and lint is 8 or more.
○: The number of fluff and lint evaluated that there is little or less is 5 or more and 7 or less.
X: The number of persons evaluated that there is no or little amount of fluff and lint is 4 or less.
In this evaluation method, the fiber molded body evaluated as “◯” or “◎” was evaluated as having good fuzzing, small lint amount, and good repeated compression durability.

<(Example 1) Sample A>
The low melting point component is HDPE (high density polyethylene; melting point 130 ° C., MI16), and the high melting point component is PET (polyethylene terephthalate; melting point 250 ° C., IV 0.68). A bundle of continuous fibers with a concentric sheath-core type composite fiber having a zigzag crimp of 2.54 cm (sheath core ratio is 50/50, 3.3 dtex on a volume basis) is extended in one direction by the toe opening method. It was opened evenly by tension and relaxation. The obtained fiber layer having a basis weight of 20 g / m ² , a thickness of about 1 mm, and a width of about 500 mm is pushed into a box whose opening area decreases from the inlet toward the outlet, and the outlet opening is 10 mm long and 500 mm wide. Thus, a fiber layer in which a folded structure was formed in the box was obtained.
The fiber layer having the folded structure is subjected to a heat treatment using a hot air circulating heat treatment machine under conditions of a circulating air speed of 1.5 m / s, a hot air temperature of 130 ° C., and a conveyor speed of 8.5 m / min. Got.
The obtained fiber molded body forms a ridge and forms a continuous curved surface with fiber layers extending from both sides of the ridge in the thickness direction of the fiber molded body, and forms a ridge and extends in the thickness direction of the fiber molded body. Adjacent fiber layers were bonded and adhered to each other in the thickness direction of the fiber molded body by heat fusion using a low melting point component of the fiber. When trying to peel the adjacent fiber layers of the ridges, a part of the fibers of one fiber layer bite into the inside of the other adjacent fiber layer (entangled) and thermally bonded to improve the peel strength. A contributing situation was observed.

<(Example 2) Sample B>
Eccentric sheath-core composite with latent crimping properties, wherein the low melting point component is HDPE (high density polyethylene; melting point 130 ° C., MI16) and the high melting point component is PP (polypropylene homopolymer; melting point 160 ° C., MFR16). Tows of fibers (sheath core ratio 50/50, 3.3 dtex on a volume basis) were spread evenly by applying tension and relaxation by the tow opening method. A fiber molded body was obtained according to the production method of Sample A, except that a fiber bundle layer having a basis weight of 25 g / m ² , a thickness of about 2.5 mm, and a width of about 500 mm was obtained. In the fibers constituting the fiber molded body, 10-15 peaks / 2.54 cm of spiral crimps were expressed.
The obtained fiber molded body forms a ridge and forms a continuous curved surface with fiber layers extending from both sides of the ridge in the thickness direction of the fiber molded body, and forms a ridge and extends in the thickness direction of the fiber molded body. Adjacent fiber layers were bonded and adhered to each other in the thickness direction of the fiber molded body by heat fusion using a low melting point component of the fiber. When trying to peel the adjacent heel fiber layers, a part of the fibers of one fiber layer bite into the other adjacent fiber layer (entangled) and thermally bonded, improving the peel strength. It is estimated that

<(Comparative Example 1) Sample C>
The low melting point component is HDPE (high density polyethylene; melting point 130 ° C., MI16), and the high melting point component is PET (polyethylene terephthalate; melting point 250 ° C., IV 0.68). Concentric sheath-core type composite short fiber with a zigzag crimp of 2.54 cm (sheath core ratio is 50/50, 3.3 dtex × 51 mm on a volume basis) by a card processing method, a basis weight of 20 g / m ² , thickness After forming a fiber layer having a width of about 1.5 mm and a width of about 500 mm, a fiber molded body having a folded structure was obtained according to the method of Sample A.

<(Comparative Example 2) Sample D>
The low melting point component is HDPE (high density polyethylene; melting point 130 ° C., MI16), and the high melting point component is PET (polyethylene terephthalate; melting point 250 ° C., IV 0.68). 50/50) on the basis of the capacity is accumulated on the conveyor by the spunbond method to obtain a fiber layer (fleece: 2.2 dtex) having a basis weight of 20 g / m ² , a thickness of about 0.3 mm, and a width of about 500 mm. According to the method, a fiber molded body having a folded structure was obtained.

  Table 1 shows the evaluation results of Examples and Comparative Examples.

  The fiber molded body having a cushioning property of the present invention is excellent in flexibility, and even when it is repeatedly compressed, it has good fuzzing properties and a small amount of lint. It can be suitably used in the construction field. Further, since the fiber molded body of the present invention has a folded structure, it has high vertical resilience and good texture, and therefore can be suitably used for a cushion material or the like. Moreover, since the fiber molded body of the present invention has many voids in the fiber molded body and is excellent in heat retaining properties and sound insulating properties, it can be suitably used for heat insulating materials, sound insulating materials and the like.

DESCRIPTION OF SYMBOLS 1 Fiber molded object 2 ３ 3 Fiber layer 4 Thickness direction of fiber molded object

Claims (6)

A fiber layer formed by opening a bundle of continuous fibers that have crimps and extend in one direction has a structure that is folded in the direction in which the continuous fibers extend so that wrinkles repeatedly appear on the surface of the fiber layer. A fiber molded body comprising:
The fiber molded body forms, on the surface of the fiber molded body, wrinkles having a shape compressed and flattened in the thickness direction of the fiber molded body, or
The fiber molded body forms a wrinkle and forms a continuous curved surface with fiber layers extending in the thickness direction of the fiber molded body from both sides of the wrinkle,
A fiber molded body in which adjacent fiber layers of ridges that form ridges and extend in the thickness direction of the fiber molded body are in close contact with each other in the thickness direction of the fiber molded body.   The continuous fibers are heat-fusible continuous fibers, and the adjacent fiber layers are bonded to each other in the thickness direction of the fiber molded body by bonding the heat-bonding continuous fibers of the fiber layer. The fiber molded body according to claim 1.   At least part of the heat-fusible continuous fibers constituting the fiber layers that are in close contact with each other in the thickness direction of the fiber molded body are entangled in the adjacent fiber layers, The fiber molded body according to claim 2, wherein the heat-fusible continuous fibers constituting the fiber layer and the entangled heat-fusible continuous fibers are joined by heat-sealing.   A fiber molded body obtained by further imprinting a stamp pattern on the surface side of the fiber molded body according to any one of claims 1 to 3 which has wrinkles.   The fiber molded body according to any one of claims 1 to 4, wherein the continuous fiber is a sheath-core type composite continuous fiber having polyester as a core and polyethylene as a sheath.   The product obtained using the fiber molded object of any one of Claims 1-5.