JP2003286642A - Three-dimensional sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional sheet which has an excellent feeling, excellent thermo compression bonding properties to other materials, and the like, and forms a desired unevenness when produced. <P>SOLUTION: This three-dimensional sheet 10 has a constitution that a second fiber layer 2 which consists essentially of a heat-nonshrinkable fiber and comprises a heat-fusible fiber is laminated to one side of a first fiber layer 1 comprising a heat-shrunk heat-shrinkable fiber, and a third fiber layer 3 comprising a heat-fusible fiber is laminated to the other side of the first fiber layer 1. The first to the third fiber layers form heat fusion parts 4 of a prescribed pattern in the three-dimensional sheet. The heat fusion parts 4 is extended from the second fiber layer 2 to the third fiber layer 3 and the second fiber layer 2 forms projected shapes except the heat fusion parts 4. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional sheet having a desired structure and a bulky structure.

[0002]

Prior Art and Problems to be Solved by the Invention Patent 3
131557 discloses a non-heat-shrinkable fiber on one side of a first fiber layer containing heat-shrinkable fibers and heat-bonding fibers made of a resin having a melting point lower than the heat-shrinking start temperature of the heat-shrinkable fibers. A wrinkle-free nonwoven fabric formed by laminating a second fiber layer is described. Both fiber layers are integrated in the thickness direction by linear heat fusion, the heat fusion portion is a concave portion, and the space between the heat fusion portions is a convex portion, and a large number of streaks are formed on the second fiber layer. Wrinkles are formed. This multi-wrinkled nonwoven fabric is obtained by superimposing the first fiber layer and the second fiber layer, and after integrating both fiber layers by heat fusion at a temperature lower than the heat shrinkage initiation temperature of the heat shrinkable fiber. It can be obtained by blowing hot air having a temperature not lower than the heat shrinking temperature to heat shrink the heat shrinkable fiber. However, in this nonwoven fabric, the heat fusion between the first fiber layer and the second fiber layer depends on the heat fusion fibers contained in the first fiber layer in an amount of 30 to 50% by weight or more. There is a limit to the bonding power. Therefore, during heat shrinkage of the first fiber layer, during post-processing of the nonwoven fabric, and during use, the heat-sealed portion is likely to peel off, and as a result, the uneven pattern may become unclear or the desired uneven shape may not be obtained. In addition, since the shrinking temperature of the heat-shrinkable fiber is higher than the melting point of the heat-sealing fiber, the heat-sealing fiber melts during shrinkage to deteriorate the texture, which is unsuitable for a sheet that comes into direct contact with the skin. In order to increase the bonding strength of both fiber layers, it is possible to increase the ratio of the heat-fusible fibers contained in the first fiber layer or increase the temperature and pressure during the heat-sealing process, but in the former, There is a possibility that the ratio of the heat-shrinkable fibers is reduced and the shrinkability of the first fiber layer becomes insufficient, so that the desired uneven shape cannot be obtained. On the other hand, in the latter case, as a result of the heat-sealed portion becoming harder, the flexibility of the entire sheet decreases and the texture deteriorates. When the above-mentioned wrinkle-resistant nonwoven fabric is used by being fixed to another material or the like,
The surface on the first fiber layer side will be fixed toward another material, etc., but a large amount of heat-sealing fibers cannot be used for the first fiber layer in order to secure contraction force, and Since thermocompression bonding such as hot embossing is performed at a temperature not higher than the shrinkage temperature of the heat shrinkable fiber, the heat shrinkable fiber cannot be melted, and even if it is fixed by thermocompression bonding such as hot embossing, sufficient bonding strength cannot be obtained.

Therefore, an object of the present invention is to have a good texture,
It is an object of the present invention to provide a three-dimensional sheet which is excellent in thermocompression bonding property with respect to other materials and which can be formed with desired unevenness during manufacturing. Another object of the present invention is to provide a method for fixing a three-dimensional sheet, which can firmly bond a three-dimensional sheet using heat-shrinkable fibers to an object to be fixed made of a fiber material.

[0004]

DISCLOSURE OF THE INVENTION The present invention is directed to a second fiber layer containing a non-heat-shrinkable fiber as a main component and a heat-fusible fiber on one surface of a first fiber layer containing a heat-shrinkable heat-shrinkable fiber. A three-dimensional sheet in which a third fiber layer containing a heat-fusible fiber is laminated on the other surface of the first fiber layer, wherein the first to third fiber layers have a predetermined pattern on the three-dimensional sheet. A heat-sealing portion is formed, the heat-sealing portion extends from the second fiber layer to the third fiber layer, and the second fiber layer has a convex shape in a portion other than the heat-sealing portion. The above-mentioned object is achieved by providing a three-dimensional sheet (hereinafter, referred to as the first invention means this invention).

According to the present invention, a first fiber layer containing heat-shrinkable fibers is laminated on one side with a second fiber layer mainly containing non-heat-shrinkable fibers and containing heat-fusible fibers. A method of fixing a three-dimensional sheet in which a second fiber layer forms a three-dimensional sheet having a predetermined pattern of joints on an object to be fixed made of a fiber material, with the second fiber layer side being the object side. hand,
A third fiber layer containing a heat-fusible fiber is interposed between the three-dimensional sheet and the object to be fixed, and by heat embossing,
The above object is achieved by providing a method for fixing a three-dimensional sheet that integrates these (hereinafter, referred to as the second
When we say an invention, we mean this invention).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described based on its preferred embodiments with reference to the drawings. In Figure 1,
Three-dimensional sheet 1 as one embodiment of the present invention (first invention)
A cross-sectional view of 0 is schematically shown. Three-dimensional sheet 10
Has a three-layer structure in which the second fiber layer 2 is laminated on one surface of the first fiber layer 1 containing heat-shrinkable fibers, and the third fiber layer 3 is laminated on the other surface of the first fiber layer 1. is doing. First fiber layer 1
Is composed of a collection of fibers. On the other hand, each of the second fiber layer 2 and the third fiber layer 3 is composed of an aggregate of fibers having a different type and / or composition from the fibers forming the first fiber layer 1. The second fiber layer 2 and the third fiber layer 3 are composed of an aggregate of fibers of the same type and combination, or an aggregate of fibers of different types and / or combinations.

When the three-dimensional sheet 10 is viewed in a plan view, the three-dimensional sheet 10 is provided with the heat-sealed portions 4 having a diamond-shaped lattice pattern shown in FIG. The heat fusion portion 4 is formed by partially thermocompressing the first to third fiber layers in the laminated state. The heat-sealing part 4 extends from the second fiber layer 2 to the third fiber layer 3. The joint between the second fiber layer and the first fiber layer and the joint between the first fiber layer and the third fiber layer completely overlap each other when the three-dimensional sheet 10 is viewed in plan. The heat fusion portion 4 is formed by melting and solidifying the heat fusion resin. As will be described later, the heat fusion resin is
Preferably, it is contained in the second fiber layer 2 and the third fiber layer 3 in the form of a heat-bonding fiber containing the same, and the heat-bonding resin of both of these fiber layers is completely different from the resin of the first fiber layer. Even if they are not melted, they melt and permeate and bond to each other, enabling three layers of bonding. Further, it is preferably contained in the first fiber layer, if desired. It is preferable that the heat-sealing portion 4 extends from the second fiber layer to the third fiber layer in all of the individual heat-sealing portions of the three-dimensional sheet 10, and the individual heat-sealing portions are the portions. It is preferable to cover the entire area of the three-dimensional sheet in the thickness direction. Although the individual heat-sealing portions in the present embodiment are circular, the shape of each heat-sealing portion may be elliptical, triangular, rectangular, or a combination thereof. Further, the joint portion may be formed in a continuous shape, for example, a linear shape such as a straight line or a curved line. The formation pattern of the heat-sealed portion 4 is, for example, FIG. 2B and FIG.
It is also possible to have a pattern as shown in.

The heat-sealed portion 4 with respect to the area of the three-dimensional sheet 10
The area ratio (area of the heat-sealing portion 4 per unit area of the three-dimensional sheet 10) depends on the specific application of the three-dimensional sheet 10, but the bonding strength of the first to third fiber layers is sufficiently high. The heat-sealing part 4 is formed from the point that the heat-sealing part 4 is formed, and the convex three-dimensional shape is sufficiently formed by the deformation of the second fiber layer to develop the bulkiness.
3 to 5 after formation of the first fiber layer 1 and before heat shrinkage of the first fiber layer 1.
0%, especially 5 to 35%, and 6 to 6 after heat shrinkage.
It is preferably 90%, particularly preferably 10 to 70%.

The three-dimensional sheet 10 has the first laminated state.
-The third fiber layer is manufactured by partially thermocompressing and integrating the third fiber layer and then heat-treating at a temperature equal to or higher than the shrinkage start temperature of the heat-shrinkable fiber contained in the first fiber layer 1. Due to the heat shrinkage of the layer, the portion of the second fiber layer 2 other than the heat-sealed portion 4 has a convex shape. In the present embodiment, as shown in FIG. 2A, the three-dimensional sheet 10 has a large number of closed regions surrounded by the heat-sealed portions 4 having a diamond-shaped lattice pattern, and the closed regions are closed. In each region, the second fiber layer 2 is transformed into a dome-shaped convex shape. On the other hand, the heat-sealing portion 4 is relatively recessed as compared with the convex portion of the second fiber layer 2 (also referred to as the convex portion 5), whereby the second fiber layer side of the three-dimensional sheet 10 is provided. The surface is formed with an uneven shape composed of a large number of convex portions and concave portions. In this embodiment, due to the contraction of the first fiber layer 1, a similar uneven shape is formed on the third fiber layer 3 side.

The first fiber layer 1 contains heat-shrinkable fibers. This heat-shrinkable fiber, in the three-dimensional sheet 10,
It is in a heat-shrinked state. As heat shrinkable fiber,
Known materials can be used without particular limitation. When latently crimpable fibers are used as the heat shrinkable fibers, the first fiber layer 1
Is imparted with an elastomeric property, and the three-dimensional sheet 10 as a whole exhibits an elastomeric property, which is preferable. When the three-dimensional sheet 10 has an elastomeric property, when the three-dimensional sheet 10 is used as a constituent member of a disposable absorbent article, which will be described later, the three-dimensional sheet 10 has good followability with respect to the motion of the wearer and the fit of the absorbent article. Is improved and liquid leakage is effectively prevented, which is preferable.

The latently crimpable fibers are, for example, eccentric core-sheath type composite fibers or side-by-side type composite fibers containing two kinds of thermoplastic polymer materials having different shrinkage rates as components. Examples thereof include those described in Japanese Patent Application Laid-Open No. 9-296325 and Japanese Patent No. 2759331. Examples of the two types of thermoplastic polymer materials having different shrinkages include, for example, a combination of ethylene-propylene random copolymer (EP) and polypropylene (PP),
Examples include a combination of polyethylene terephthalate (PET) and a copolymer of polyethylene terephthalate and polyethylene isophthalate (CoPET). The heat shrinkable fibers may be staple staple fibers or filament filaments. Its thickness is 1-7 dt
Ex is preferable. The heat shrinkage initiation temperature of the heat shrinkable fiber may be 90 to 110 ° C., for example. The heat shrinkage start temperature means an actually measured temperature when the fiber is placed in a furnace capable of heating and is heated at a constant rate and the fiber substantially starts shrinking.

The first fiber layer 1 may be composed of 100% heat-shrinkable fibers or may contain other fibers. Examples of other fibers contained in the first fiber layer 1 include heat fusion fibers described later, for example, heat fusion fibers contained in the second and / or third fiber layers. Even when the first fiber layer 1 contains other fibers, when the three-dimensional sheet is manufactured,
From the viewpoint that the shrinkage of the heat-shrinkable fiber is not hindered, the amount of the heat-shrinkable fiber is preferably 70% by weight or more, and particularly preferably 90 to 100% by weight, based on the weight of the first fiber layer 1.

Examples of the form of the first fiber layer 1 before heat shrinking include a web in which the constituent fibers are unbonded, or a nonwoven fabric. Examples of the first fiber layer 1 in the form of a web include a web containing heat-shrinkable fibers and formed by the card method. Examples of the first fiber layer 1 in the form of a non-woven fabric include non-woven fabrics containing heat-shrinkable fibers and manufactured by various non-woven fabric manufacturing methods. Examples of the non-woven fabric manufacturing method include a heat fusion method, a hydroentangling method, a needle punch method, a solvent bonding method, a spun bond method, and a melt blown method.

The second fiber layer 2 is mainly composed of non-heat-shrinkable fibers. The term "non-heat-shrinkable fiber" as used herein refers to a fiber that does not exhibit heat-shrinkability, and a material that exhibits heat-shrinkability, but does not substantially heat at a heat-shrinking initiation temperature of the heat-shrinkable fiber contained in the first fiber layer or lower. Includes both non-shrinkable fibers. Second
The amount of non-heat-shrinkable fibers in the fiber layer 2 is at least 70% by weight or more, preferably 90% by weight or more, and particularly 100% by weight, based on the weight of the second fiber layer 1.
It is preferable because the first fiber layer becomes more three-dimensional. From the viewpoint of adjusting the three-dimensionality and shrinkability, the second fiber layer may contain about 10 to 30% by weight of the same heat-shrinkable fiber as the heat-shrinkable fiber in the first fiber layer. preferable.

The second fiber layer 2 and the third fiber layer 3 each contain a heat-fusible fiber. The heat-fusible fiber contains a heat-fusible resin, and the fibers can be fused by melting and solidifying the resin. The heat-fusible fibers contained in the second fiber layer 2 and the third fiber layer 3 may each contain a heat-fusion resin having a lower melting point than the melting point of the heat-shrinkable fibers contained in the first fiber layer 1. It is preferable from the viewpoint of further improving the bonding strength of the heat-sealed portion. When the heat-shrinkable fiber in the first fiber layer is a core-sheath (eccentric or concentric) composite fiber or a side-by-side composite fiber, it is included in the second and third fiber layers. The heat-fusible fiber preferably contains a resin having a melting point lower than the melting points of the heat-sealing components of both the sheath component of the core-sheath type conjugate fiber or the side-by-side type conjugate fiber. Here, the melting point of the heat-shrinkable fiber means a peak value when the heat of fusion is measured by DSC (differential scanning calorimeter).

The melting point of the heat-fusible resin in the heat-fusible fibers contained in the second fiber layer 2 and the third fiber layer 3 is 10 ° C. or higher than the melting point of the heat-shrinkable fibers of the first fiber layer, especially 20. It is preferable that the temperature is not lower than 0 ° C. because the heat-fusible fiber contained in the second fiber layer can be melted and adhered without shrinking the first fiber layer which touches the skin. When the heat-fusible fiber is a multicomponent composite fiber, it is preferable that the heat-melting resin having the lowest melting point therein is lower than the melting point of the heat-shrinkable fiber of the first fiber layer. The melting point of the heat-fusible resin in the heat-fusible fibers contained in the second fiber layer 2 and the third fiber layer 3 is 30 ° C. or higher than the heat-shrink temperature of the heat-shrinkable fibers of the first fiber layer, It is particularly preferable that the temperature is 40 ° C. or higher, because the heat-fusible fibers contained in the second fiber layer can be melted without shrinking the first fiber layer to achieve sufficient adhesive strength.

Further, the melting point of the heat-sealing resin contained in the heat-sealing fibers contained in the second fiber layer 2 and the melting point of the heat-sealing resin contained in the heat-sealing fibers contained in the third fiber layer 3 are the same. Or the difference between the melting points of these two heat-sealing resins is within 20 ° C., especially 1
Within 0 ° C, the bonding strength of the first to third fiber layers can be further improved, and the temperature condition of heat treatment for integrating these can be performed at a relatively low temperature. It is preferable because the texture of the sheet can be further improved.

From the viewpoint of improving the bonding strength between the fiber layers in the heat-sealing part 4 and improving the texture of the three-dimensional sheet, the amount of the heat-sealing fibers contained in the second fiber layer is the same as that of the second fiber layer 2. 70 to 100% by weight, especially 90 to
It is preferably 100% by weight. The amount of the heat-sealing fibers contained in the third fiber layer is such that the bonding strength between the fiber layers in the heat-sealing portion 4 is improved and the texture of the three-dimensional sheet is improved, and other materials, particularly the fiber material. 7 to the weight of the third fiber layer 2 from the viewpoint of improving the thermocompression bonding property to
It is preferably from 0 to 100% by weight, particularly preferably from 90 to 100% by weight.

Examples of the heat-sealing fibers contained in the second fiber layer 2 and the third fiber layer 3 include polyethylene (PE), polypropylene (PP), polyethylene-propylene copolymer, polyethylene terephthalate (PET), and poly. Polyesters such as butylene terephthalate, polyethylene terephthalate-ethylene isophthalate copolymer, polyamide ethylene acrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, Examples of the fiber include ethylene-ethyl methacrylate copolymer and ethylene-methyl acrylate-acrylic terpolymer. Further, a core-sheath type composite fiber or a side-by-side type composite fiber made of a combination of these thermoplastic polymer materials can also be used. These fibers may be staple staple fibers or filament filaments. The thickness is preferably about 1 to 7 dtex. First
When the fiber layer 1 contains a heat-sealing fiber, the heat-sealing fiber is
The same thing as these can be used.

Examples of the form of the second and third fiber layers 2 before the first fiber layer 1 is heat-shrinked include a web or a nonwoven fabric in which the constituent fibers are unbonded. Second before heat shrink
The configurations of the fiber layer and the third fiber layer 2 may be the same or different. If the form of the second fiber layer is particularly a web form, it becomes easy to change the area or shape of the second fiber layer 2 due to shrinkage, and the second fiber layer 2 can be raised in a convex shape in the thickness direction. It is preferable because it becomes easy. Moreover, since the raised convex portions are filled with fibers, a sheet having a rich cushioning property and a soft texture can be obtained, which is preferable. Second fiber layer 2 and / or third fiber layer 3
Is in the form of a web, the web can be formed, for example, by the card method. On the three-dimensional sheet 10 in which the second fibrous layer 2 is formed from such a web, convex portions 5 that are bulky and filled with the fibers constituting the web are formed, and the fibers are arranged along the convex portions 5. Orient. In particular, when the second fiber layer 2 is in the form of a web formed by the card method, the second fiber layer 2 has an extremely sparse structure, and the three-dimensional sheet 10 of the present invention allows the high-viscosity liquid to permeate and retain. Is possible. Further, the compressive deformability when the three-dimensional sheet 10 is compressed in the thickness direction also becomes high. Examples of the highly viscous liquid include loose stools or menstrual blood, detergents or moisturizers for humans, or detergents for objectives. On the other hand, when the form of the second fiber layer is a non-woven fabric before joining and shrinking, there are advantages that the transportability is good and the strength is large. Further, since it is not necessary to fuse the constituent fibers of the second fiber layer after the bonding with the first fiber layer, there is an advantage that the selection range of the shrinkage temperature is wide.

The three-dimensional sheet 10 of this embodiment is, for example,
Each of the first to third fiber layers is manufactured using a known method, and the first fiber layer 1 is provided between the second fiber layer 2 and the third fiber layer 3.
After sandwiching them, by a hot embossing roll device consisting of concavo-convex rolls or a concavo-convex roll and a smooth roll, the laminated first to third fiber layers are partially thermocompression-bonded in a predetermined pattern, Then, the heat-shrinkable fiber contained in the first fiber layer 1 is obtained by shrinking the heat-shrinkable fiber by heat treatment at a heat shrinkage starting temperature or higher. As the heat treatment method, in addition to a method of passing hot air through or blowing hot air to the laminated and integrated first to third fiber layers, a method of contacting with microwave, steam, infrared ray, heat roll, or the like can be used.

According to the three-dimensional sheet 10 of this embodiment, the heat-sealing portion 4 having a predetermined pattern is formed so as to extend from the second fiber layer to the third fiber layer when the three-dimensional sheet 10 is viewed in a plan view. Therefore, the bonding strength from the second fiber layer to the third fiber layer in the heat fusion portion 4 can be improved. Therefore, for example, thermocompression bonding during manufacturing can be performed under relatively low temperature conditions while sufficiently maintaining sufficient shrinkability of the first fiber layer and the bonding strength from the second fiber layer to the third fiber layer. . Therefore, it is possible to obtain a three-dimensional sheet which is soft and has a good texture.

Further, the third fiber layer side is subjected to thermocompression bonding (heat embossing or the like) toward the other material or the like (also referred to as the fixed object 6) to which the three-dimensional sheet 10 is to be fixed, whereby the three-dimensional sheet is obtained. 10 can be firmly thermocompression-bonded to the other material or the like, and peeling does not easily occur between the three-dimensional sheet 10 and the fixed object.

FIG. 3 shows the three-dimensional sheet 10 having the above-mentioned structure.
The third fiber layer side was fixed to the absorbent body 61 and the leak-proof sheet 62 of the sanitary napkin (absorbent article) as the fixed object 6 made of a fibrous material by hot embossing with the third fiber layer side being the fixed object side. The status is shown. That is, the three-dimensional sheet 10
Is thermocompression bonded to the surface of the absorbent body 61 on the skin contact surface side by heat embossing with a heat sealing device in the central region of the sanitary napkin. An annular central leak-proof groove is formed on the contact surface. In addition, the three-dimensional sheet 10 is thermo-compressed onto the leak-proof sheet arranged on the absorbent body 61 by heat embossing by a heat sealing device at both sides in the longitudinal direction of the sanitary napkin. Crimping part 72
Thus, a pair of side leakproof grooves are formed on both sides of the central leakproof groove on the skin contact surface of the sanitary napkin. The surface of the absorber in the thermocompression bonding portion 71 is formed by a mount made of a cellulosic fiber material, and the leak preventive sheet 62 in the thermocompression bonding portion 72 is formed by laminating polyethylene on the cellulosic fiber material. It is configured. Since the leak-proof sheet 62 has better adhesiveness, it was used with the laminate (polyethylene) side facing the surface sheet side (the same applies to Examples and Comparative Examples described later).

In both thermocompression bonding parts 71, 72, the heat-sealing resin in the third fiber layer is melted and solidified in a state in which the heat-melting resin in the third fiber layer bites between the constituent fibers of the object 6 to be fixed. The separation between the three-dimensional sheet 10 and these fixed objects 6 is unlikely to occur. As the heat-sealing device, a heat-sealing device for forming a groove or a heat-sealing device for forming an end-sealing portion, which has been conventionally used in sanitary napkins, disposable diapers and the like, can be used. Incidentally, in FIG. 3, the three-dimensional sheet 1
Illustrations of irregularities and the like formed on the surface of 0 are omitted. In the sanitary napkin shown in FIG. 3, the three-dimensional sheet 10 is used.
Is used as a liquid-permeable surface material (top sheet), and a liquid-retaining absorber 61 is interposed between the three-dimensional sheet 10 and the liquid-impermeable back material (back sheet) 8. There is. The three-dimensional sheet 10 is fixed to the leak preventive sheet 62 and the back surface material 8 with the hot melt adhesive 91 in the vicinity of both sides of the absorber 61, and the leak preventive sheet 62 is fixed to the back surface material 8 with the hot melt adhesive 92. It is fixed.

FIG. 4 is a view showing a preferred embodiment of the method for fixing a three-dimensional sheet of the present invention (second invention). The three-dimensional sheet 10 'shown in FIG. 4 is a first fiber layer 1 containing heat-shrinkable fibers.
The second fiber layer 2 mainly composed of non-heat-shrinkable fibers and containing heat-fusible fibers is laminated on one side of the first and second fiber layers 1 and 2, and the heat-fusion-bonded part having a predetermined pattern is formed. It is a three-dimensional sheet 10 ′ forming (joint portion) 4. Three-dimensional sheet 1
0'has the same configuration as the above-described three-dimensional sheet 10 except that the third fiber layer is not laminated on the other surface of the first fiber layer 1. In the three-dimensional sheet 10 ', the first fiber layer 1 and the second fiber layer 2 are heat-sealed in the same pattern as that of the three-dimensional sheet 10, so that the heat-sealed portion 4 having the predetermined pattern is formed. . First fiber layer 1 and second fiber layer 2
The respective preferable configurations and the like are the same as those of the first and second fiber layers in the three-dimensional sheet 10.

In the method for fixing a three-dimensional sheet according to this embodiment, the three-dimensional sheet 10 'is used as an absorbent body 6 of a sanitary napkin (absorbent article) as an object 6 to be fixed made of a fiber material.
1, when fixing by heat embossing, between the second fiber layer 2 of the three-dimensional sheet 10 ′ and the object 6 to be fixed, the first sheet containing the heat-fusible fiber produced separately from the three-dimensional sheet 10 ′. Heat embossing is performed from the side of the three-dimensional sheet 10 ′ with three fiber layers interposed. According to the fixing method of the present embodiment, in the portion subjected to the heat embossing process by the heat seal device, the heat of the heat fusion fibers in the first fiber layer and the third fiber layer is the same as in the three-dimensional sheet 10 described above. Due to the solidification of the fusion resin, the second fiber layer 2 to the third fiber layer 3 are extremely strongly joined and integrated, and at the time of hot embossing,
Since the heat-fusible resin in the fiber layer is melted and solidified in a state where it is entangled between the constituent fibers of the object to be fixed, sufficient bonding strength can be obtained between the three-dimensional sheet and these objects to be fixed.

The present invention is not limited to the above embodiment. The three-dimensional sheet of the present invention is preferably used as a constituent member of a disposable article that is discarded after being used once or several times. Further, it can also be used as a female material (loop material) or a pap material for hook-and-loop fasteners. In particular, it is suitable as a constituent member of disposable absorbent articles such as sanitary napkins and disposable diapers, and disposable wipers such as cleaning wipers and personal wipers. When used as a constituent member of a disposable absorbent article, for example, an absorbent article having a liquid-permeable front surface material, a liquid-impermeable back surface material, and an absorber interposed between both sheets, the constituent member thereof Part of, for example surface material,
It can be used as part of either the backing material or the side solid guard.

When the three-dimensional sheet of the present invention is used by being fixed to another material or the like (object to be fixed) by hot embossing, and in the fixing method of the three-dimensional sheet, the object to be fixed is a base of a disposable wiper. A material sheet etc. are mentioned. However, especially in the case of fixed objects made of fiber material,
In particular, the effect of the present invention is particularly remarkably exhibited in the case of a flexible fixed object that is deformed by compression, such as an absorbent body of a disposable absorbent article such as the sanitary napkin or disposable diaper described above.

The present invention will be described in more detail with reference to the following examples. However, the scope of the invention is not limited to such embodiments.

[Examples] (1) Production of first fiber layer As a heat-shrinkable fiber, a latent crimpable core-sheath type composite fiber (trade name CPP, core; polypropylene (melting point 165 to 170 ° C) manufactured by Daiwabo Polytech Co., Ltd. ), Sheath: ethylene / propylene copolymer (melting point: 145 to 147 ° C.), core / sheath weight ratio = 5/5, fineness: 2.2 dtex, fiber length: 51 mm, heat shrinkage start temperature: 90 ° C.). Using this fiber as a raw material, a web is formed with a roller card, and then an embossing roll (embossing rate 28%, temperature condition: pattern 1)
The heat roll nonwoven fabric of the first fiber layer having a basis weight of 20 g / m ² was formed by passing through a cooling roll at 45 ° C. and a speed of 80 m / min).

(2) Production of the second fiber layer As the heat-sealing fiber, core-sheath type composite fiber (trade name SHW6, core; polyethylene terephthalate (melting point 250 to 255 ° C.), manufactured by Daiwabo Polytech Co., Ltd., sheath; polyethylene (melting point 128) ˜130 ° C.), core / sheath weight ratio = 5/5, fineness 2.2 dtex, fiber length 51 mm). Using this fiber as a raw material, a web is formed with a roller card, and then an air through heat treatment machine (temperature 138 m / min,
Through air velocity of 1 m / sec, processing time of about 10 seconds), basis weight 12
An air-through non-woven fabric with a second fiber layer of g / m ² was formed.

(3) Production of Third Fiber Layer The air-through nonwoven fabric obtained in the same manner as in the production of the second fiber layer was used as the third fiber layer.

(4) Manufacture of three-dimensional sheet The above-mentioned first to third fiber layers are stacked and embossed rolls (pattern roll 145 ° C., flat roll 135 ° C., embossed pattern C dot diameter of FIG. 2 1.5 mm, area ratio 7. 4%) and pasted together. Then, immediately, heat shrink treatment with a pin tenter (up and down wind speed about 4.2 m, temperature 110 ℃ ~ 116
C., the processing time was about 14 seconds), and it was shrunk to 70% of the length before processing and 70% of the width before processing by machine setting. The basis weight of the obtained non-woven fabric was about 84 g / m ² .

[Comparative Example] A three-dimensional sheet was obtained in the same manner as in the Example, except that the three-dimensional sheet was produced in the example and then the three-dimensional sheet was laminated without using the third fiber layer and then contracted.

[Performance Evaluation] Using each of the obtained three-dimensional sheets as a surface material for absorbent articles, 100 or more sanitary napkins having a cross-sectional structure shown in FIG. 3 were continuously produced for each sheet. Each three-dimensional sheet is heat-sealed (heat-embossed) at a temperature of 190 ° C. so that the absorber 61 (basis weight: about 25
Is fixed on the surface consisting of the mount (basis weight of about 16g / m ²⁾ at 0 g / m ^2), paper (laminated basis weight was laminated to a polyethylene sheet of water-repellent by heat sealing temperature 200 ° C. (hot embossing) About 7 g / m ² , paper basis weight 16
It was fixed on a leak-proof sheet 62 made of g / m ² ). For each of the manufactured sanitary napkins, the sealing property in the thermocompression bonding portion 71 fixed on the absorber 61 and the thermocompression bonding portion 72 fixed on the leak-proof sheet 62 is visually observed for the presence or absence of floating of the pattern portion, The number of napkins judged to have no problem in the appearance of the thermocompression bonded part (good appearance) according to the following evaluation criteria is shown in Table 1 (N = 100).

<Evaluation Criteria> Appearance is good; the seal block is adhered to the base material clearly according to the mold, and there is no floating. Poor appearance; Even if a part of the seal block mold is unclear, or part or all There is a float

[0038]

[Table 1]

As is clear from the results shown in Table 1, the three-dimensional sheets of the examples (invention products) are excellent in thermocompression bonding to the absorbent body and the leak-proof sheet, and other materials such as fiber materials are preferable. It can be seen that the thermocompression bonding property with respect to the fixed object is excellent. On the other hand, in the three-dimensional sheet of the comparative example, there are some sheets in which the mold of the seal block is slightly unclear or partially or entirely floated, which causes a problem in product performance.

[0040]

The three-dimensional sheet of the present invention has a good texture,
It is excellent in thermocompression bonding to other materials and can form desired unevenness during manufacturing. According to the method for fixing a three-dimensional sheet of the present invention, a three-dimensional sheet using heat-shrinkable fibers can be firmly bonded to an object to be fixed made of a fiber material.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a three-dimensional sheet as one embodiment of a three-dimensional sheet of the present invention (first invention) together with an object to be fixed when the three-dimensional sheet is fixed and used.

FIG. 2 is a plan view showing an example of a formation pattern of a heat-sealing portion formed on a three-dimensional sheet.

FIG. 3 is a schematic cross-sectional view showing a cross section in the width direction of a sanitary napkin (absorbent article) manufactured using a three-dimensional sheet.

FIG. 4 is a schematic cross-sectional view showing an embodiment of a method for fixing a three-dimensional sheet of the present invention (second invention).

[Explanation of symbols]

10,10 'three-dimensional sheet 1 First fiber layer 2 Second fiber layer 3rd fiber layer 4 Thermal fusion part 5 convex

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) A61F 13/511 A61F 13/18 340 13/514 360 13/539 A41B 13/02 F B32B 5/26 F term (reference) 3B029 BC02 BC07 4C003 BA02 BA03 BA08 DA01 EA02 GA03 4C098 AA09 CC08 DD10 DD25 DD26 4F100 AK04 AK07 AK42 AK64 BA03 BA07 BA10A BA10B BA10C BA14 DD01 DD04B DG01A DG01B DG01C DG06 DG15 DG20 EH012 EJ402 EJ422 GB72 JA03A JA04B JA04C JL12 JL12B JL12C YY00B YY00C 4L047 BA05 BA08 BA23 CA05 CC04 CC05

Claims (7)

[Claims] 1. A first fiber layer comprising a first fiber layer containing heat-shrinkable fibers that has been heat-shrinked, and a second fiber layer mainly containing non-heat-shrinkable fibers and containing heat-fusible fibers, which is laminated on one surface of the first fiber layer. On the other side of
A three-dimensional sheet in which a third fiber layer containing heat-fusible fibers is laminated, wherein the first to third fiber layers form a heat-fusion portion of a predetermined pattern on the three-dimensional sheet. The dress is
A three-dimensional sheet that extends from the second fiber layer to the third fiber layer, and the second fiber layer has a convex portion other than the heat-sealing portion. 2. The three-dimensional sheet according to claim 1, wherein the heat fusible fibers contained in the second and third fiber layers contain a heat fusible resin having a melting point lower than that of the heat shrinkable fibers. 3. The melting point of the heat-sealing resin contained in the heat-sealing fiber contained in the second fiber layer and the melting point of the heat-sealing resin contained in the heat-sealing fiber contained in the third fiber layer are the same. The three-dimensional sheet according to claim 1 or 2, wherein the difference between the melting points of these two heat-sealing resins is within 20 ° C. 4. The three-dimensional sheet according to claim 1, which is fixed to an object to be fixed made of a fibrous material by hot embossing with the third fiber layer side being the object to be fixed side. 5. The three-dimensional sheet according to claim 4, wherein the fixed object is an absorbent body of an absorbent article such as a sanitary napkin and a disposable diaper. 6. A first fiber layer containing heat-shrinkable fibers, and a second fiber layer mainly containing non-heat-shrinkable fibers and containing heat-fusible fibers is laminated on one surface of the first fiber layer. The fiber layer
A method for fixing a three-dimensional sheet, which forms a joint portion having a predetermined pattern, to an object to be fixed made of a fibrous material, with the second fiber layer side being the side of the object to be fixed, By interposing a third fiber layer containing a heat-fusible fiber between the object to be fixed and heat embossing,
A method of fixing a three-dimensional sheet that integrates these. 7. The method for fixing a three-dimensional sheet according to claim 6, wherein the object to be fixed is an absorbent body of an absorbent article such as a sanitary napkin or a disposable diaper.