Laminate sheet

Abstract

To propose a novel laminate sheet in which a nonwoven fabric is used instead of a polyurethane foam sheet without impairing a good appearance exhibited by a conventional laminate sheet.SOLUTION: There is provided a laminate sheet comprising a skin (10) and a nonwoven fabric (20). The nonwoven fabric (20) includes first fibers (21f) made of a first resin (21) and second fibers (22f) made of a second resin (22) having a melting point lower than that of the first resin (21). The skin (10) and the nonwoven fabric (20) are bonded and laminated at an adhesive portion (30) containing a third resin (31). The melting point of the second resin (22) is 100°C or higher and 120°C or lower and the melting points of the first resin (21), the second resin (22) and the third resin (31) have a relation represented by the following formula (1). The formula (1): melting point of second resin<melting point of third resin<melting point of first resin.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminate sheet, and more particularly to a laminate sheet suitable for use as a core material or a skin material for various articles. [Background technology]

[0002] To improve the surface appearance of various core materials or articles (hereinafter also referred to as core materials, etc.), such as automobile interior materials such as vehicle ceilings, instrument panels, and door trims, railroad car and aircraft interior materials such as ceilings and trims, fabrics, architectural interior materials, storage cases for precision instruments, bags, etc., skin materials are attached to them. Note that the skin material referred to here refers to a member that is attached to the surface of a core material, etc., the appearance of which is visually observed during use, and can be applied not only to the outside of an article such as a storage case or bag, but also to the inside (the wall surface facing the storage space).

[0003] The above-mentioned skin material is required to have not only a beautiful appearance but also a good feel and flexibility. For this reason, conventionally, a two-layer laminated sheet in which a polyurethane foam sheet is used as the base material for the skin material and a skin of fabric, leather, synthetic leather, or the like is laminated on the polyurethane foam sheet, or a three-layer laminated sheet in which a fibrous backing material is laminated on one side of a polyurethane foam sheet and the above-mentioned skin is laminated on the other side, has been widely used.

[0004] For example, Patent Document 1 proposes an invention for a laminated sheet material in which the surface slipperiness of a polyurethane foam sheet is improved and a fiber sheet or leather sheet is laminated on at least one side of the polyurethane foam sheet. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2004-10792 A Summary of the Invention [Problem to be solved by the invention]

[0006] Polyurethane foam sheets are generally produced by slicing a block of polyurethane foam, and therefore have excellent surface smoothness. Therefore, the conventional laminated sheets using polyurethane foam sheets have the advantage that when they are pressed and bonded to the surfaces of various core materials, etc., the pockmarks derived from the polyurethane foam sheet are unlikely to appear on the surface of the skin. Therefore, when the conventional laminated sheets are laminated to the core materials, etc., by press processing such as heat press processing, they can provide processed products with good appearance. However, there has been a demand for the use of members other than polyurethane foam sheets or resins other than polyurethane for the laminated sheets.

[0007] The present invention proposes a novel laminate sheet using a nonwoven fabric instead of the polyurethane foam sheet, without impairing the excellent appearance exhibited by conventional laminate sheets. [Means for solving the problem]

[0008] The laminate sheet of the present invention includes a surface layer and a nonwoven fabric, the nonwoven fabric including first fibers made of a first resin and second fibers made of a second resin having a melting point lower than that of the first resin, The skin and the nonwoven fabric are laminated by being bonded together at an adhesive portion containing a third resin, the melting point of the second resin is 100°C or higher and 120°C or lower, and the melting points of the first resin, the second resin, and the third resin satisfy the relationship represented by the following formula (1). [Formula 1] Melting point of second resin < melting point of third resin < melting point of first resin... (1) Effect of the Invention

[0009] The laminate sheet of the present invention having the above-mentioned configuration, when used as a skin material for a core material or the like and laminated by heat and pressure to the surface of the core material or the like, has excellent appearance and can be imparted with the good feel and flexibility of a nonwoven fabric. The configuration of the laminate sheet of the present invention and the effects exerted thereby are described in detail in the description of the embodiment of the invention. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view of a laminate sheet according to a first embodiment of the present invention. [Diagram 2] FIG. 4 is a cross-sectional view of a laminate sheet which is a modified example of the first embodiment of the present invention. [Diagram 3] FIG. 2 is an explanatory diagram illustrating a method for producing a laminate sheet of the present invention. [Figure 4] FIG. 4A is an explanatory diagram illustrating components constituting an example of a pre-sheet used in manufacturing the laminate sheet of the first embodiment of the present invention, and FIG. 4B is a cross-sectional view of the example of the pre-sheet. [Diagram 5] FIG. 5A is an explanatory diagram illustrating the components constituting another example of a pre-sheet used in manufacturing the laminated sheet of the first embodiment of the present invention, and FIG. 5B is a cross-sectional view of the other example of the pre-sheet. [Figure 6] 1 is a cross-sectional view of a processed body comprising a core material having a laminate sheet of the present invention pressure-bonded to its surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention and an example of a manufacturing method thereof will be described with reference to the drawings. In all the drawings, the same components are given the same reference numerals, and duplicated descriptions will be omitted as appropriate. The various components of the present invention do not need to exist independently, and it is acceptable for multiple components to be formed as one member, for one component to be formed from multiple members, for one component to be a part of another component, for a part of one component to overlap with a part of another component, etc. In the illustrated embodiments of the present invention, for ease of understanding, certain components may be illustrated relatively large or small in the whole, but neither of these is intended to limit the dimensional ratios of each component of the present invention.

[0012] [First embodiment] A laminate sheet 100 according to a first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view of a laminated sheet 100 according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of a laminated sheet 100 according to a modified example of the first embodiment of the present invention. FIG. 3 is an explanatory diagram illustrating a method for producing the laminated sheet 100. FIG. 4A is an explanatory diagram illustrating members constituting an example (pre-sheet 110A) of a pre-sheet 110 used in the production of the laminated sheet 100, and FIG. 4B is a cross-sectional view of the pre-sheet 110A. FIG. 5A is an explanatory diagram illustrating members constituting another example (pre-sheet 110B) of a pre-sheet 110 used in the production of the laminated sheet 100, and FIG. 5B is a cross-sectional view of the pre-sheet 110B. FIG. 6 is a cross-sectional view of a processed body 200 including a core material 210 having a surface to which the laminated sheet 100 is heat-pressed.

[0013] As shown in FIG. 1, the laminated sheet 100 includes a surface layer 10 and a nonwoven fabric 20. The nonwoven fabric 20 includes a first fiber 21f made of a first resin 21 and a second fiber 22f made of a second resin 22 having a melting point lower than that of the first resin 21. The surface layer 10 and the nonwoven fabric 20 are laminated by bonding at an adhesive portion 30 containing a third resin 31, thereby forming the laminated sheet 100. In the present invention, the melting point of the second resin 22 is 100° C. or more and 120° C. or less, and the melting points of the first resin 21, the second resin 22, and the third resin 31 are related by the following formula (1). In the following description, the second resin 22 having a melting point of 100° C. or more and 120° C. or less and a lower melting point than the first resin 21 and the third resin 31 may be referred to as a "low-melting-point second resin." [Formula 2] Melting point of second resin 22 < melting point of third resin 31 < melting point of first resin 21 (1)

[0014] The laminated sheet 100 having the above-mentioned configuration has the nonwoven fabric 20 on the back surface of the epidermis 10, and is endowed with the feel and flexibility of the nonwoven fabric 20. When the laminated sheet 100 is shaped and bonded to the surface of a core material or the like by a hot press process, the second fibers 22f made of the second resin 22 having a low melting point melt and can partially bond the first fibers 21f contained in the nonwoven fabric 20 together. This allows the entire nonwoven fabric 20 to be moderately tightened, so that when the nonwoven fabric 20 and the epidermis 10 are heat-pressed to the core material or the like, the appearance of pockmarks originating from the nonwoven fabric 20 on the surface of the epidermis 10 is suppressed. As described above, the present invention can provide a laminated sheet 100 that has an excellent appearance and can be imparted with the good feel and flexibility of the nonwoven fabric 20, even though the nonwoven fabric 20 is used as the base material instead of a polyurethane foam sheet. Therefore, by bonding the laminated sheet 100 to the surface of a core material or the like by heat pressing, a processed product with a good appearance and feel can be provided.

[0015] Although the use of the laminate sheet 100 is not particularly limited, because of the above-mentioned action and effect, the laminate sheet 100 including the second fibers 22f is suitably used as a laminate sheet for heat press processing that is laminated by heat press processing onto the surface of a core material, etc. More specifically, the laminate sheet for heat press processing in the present invention is suitably used as a skin material for automobile interior members such as vehicle ceilings, instrument panels, and door trims, and railway car and aircraft interior members such as ceilings and trims. The laminated sheet 100 will be described in further detail below.

[0016] <Eidermis> The skin 10 constitutes the front side of the laminated sheet 100. There are no particular limitations on the sheet material used as the skin 10, and examples thereof include woven fabric, knitted fabric, nonwoven fabric, and synthetic leather.

[0017] The basis weight or thickness of the skin 10 is not particularly limited. When a woven fabric, knitted fabric, or nonwoven fabric is used as the skin 10, the basis weight is, for example, 100 g / m 2 More than 1000g / m 2 From the viewpoint of reducing the weight of the laminated sheet 100, the basis weight is 100 g / m or less. 2 More than 500g / m 2 It is preferable that the thickness is less than 100 g / m 2 More than 400g / m 2 It is more preferable that the surface layer 10 is equal to or less than the above range. The surface layer 10 may be a single layer made of either a woven fabric, a knitted fabric, or a nonwoven fabric, or may be a multi-layered layer made of two or more layers of the same or different sheets. When the surface layer 10 is a multi-layered layer, it is preferable that the total basis weight of the multi-layered surface layer 10 is within the above range.

[0018] When synthetic leather is used as the skin 10, the average thickness of the synthetic leather is preferably, for example, 0.5 mm or more and 2.0 mm or less, and more preferably 0.5 mm or more and 1.3 mm or less.

[0019] From the viewpoint of weight reduction, it is preferable that the skin 10 is thin. Specifically, from the viewpoint of weight reduction, the skin 10 is preferably thin with a basis weight of 100 g / m 2 More than 400g / m 2 It is preferable to use the following woven fabric, knitted fabric, nonwoven fabric, etc., or synthetic leather with an average thickness of 0.5 mm to 1.3 mm. However, when a laminated sheet is formed by layering a thin epidermis and a general nonwoven fabric, the unevenness of the surface of the nonwoven fabric is likely to affect the surface of the epidermis, and when such a laminated sheet is bonded to a core material or the like by heat processing and pressing, there is a risk that pockmarks caused by the nonwoven fabric will be clearly visible on the surface of the epidermis. However, as described above, in the laminate sheet 100, the second fibers 22f contained in the nonwoven fabric 20 can be melted by the heat during the hot press processing. As a result, the first fibers 21f around the melted second fibers 22f are bound by the second resin 22, and the nonwoven fabric 20 is tightened and exhibits good surface smoothness. Therefore, according to the present invention, it is possible to provide a laminate sheet that is lightweight by using a thin skin 10 and has a good surface appearance.

[0020] <Nonwoven fabric> The nonwoven fabric 20, which is the base material of the laminated sheet 100, contains first fibers 21f made of a first resin 21 and second fibers 22f made of a second resin 22 having a melting point lower than that of the first resin 21. The nonwoven fabric 20 in this embodiment is composed of the first fibers 21f and the second fibers 22f, but may contain any other fibers or members without departing from the spirit of the present invention.

[0021] The basis weight of the nonwoven fabric 20 is not particularly limited, but is, for example, 50 g / m 2 More than 400g / m 2 The nonwoven fabric 20 may have the following basis weight. From the viewpoint of reducing the weight of the laminated sheet 100, the basis weight of the nonwoven fabric 20 is 50 g / m 2 More than 200g / m 2 It is preferable that the thickness is less than 50 g / m 2 More than 100g / m 2From the viewpoint of providing the laminated sheet 100 with a better feel and flexibility, the basis weight of the nonwoven fabric 20 is preferably less than 100 g / m 2 More than 400g / m 2 It is preferable that:

[0022] The thickness of the nonwoven fabric 20 is not particularly limited, but for example, a nonwoven fabric 20 having an average thickness of 0.5 mm or more and 3.0 mm or less can be used. From the viewpoint of reducing the weight of the laminated sheet 100, the thickness of the nonwoven fabric 20 is preferably 0.5 mm or more and less than 1.5 mm, and more preferably 0.5 mm or more and less than 1.0 mm. Furthermore, from the viewpoint of providing the laminated sheet 100 with better feel and flexibility, the thickness of the nonwoven fabric 20 is preferably 1.5 mm or more and 3.0 mm or less.

[0023] The method for producing nonwoven fabric 20 is not particularly limited, but from the viewpoint of easily obtaining nonwoven fabric 20 with a large basis weight, it is preferable to produce nonwoven fabric 20 by the needle punch method, and from the viewpoint of being able to produce nonwoven fabric with a high production speed and good smoothness, it is preferable to produce nonwoven fabric 20 by the spunlace method.

[0024] First fiber, first resin: The first fibers 21f are composed of a first resin 21. In the laminate sheet 100, the first resin 21 is selected from resins having a melting point higher than the melting points of the second resin 22 and the third resin 31. As a result, when the adhesive portion 30 described below is formed by melting the third resin 31, and when the second resin 22 is melted during thermal processing press, the first resin 21 does not melt at all or hardly melts at all, and the nonwoven fabric 20 composed of fibers can be maintained. The first fibers 21f are produced by using the first resin 21 by a known spinning method.

[0025] The first resin 21 may be any resin that satisfies the above-mentioned melting point condition, and may be composed of one type of resin or a mixed resin containing two or more types of resin. When the first resin 21 is composed of a mixed resin, the melting point of the mixed resin may be higher than the melting points of the second resin 22 and the third resin 31.

[0026] In addition, within a range satisfying the relationship of the above-mentioned formula (1), the first fibers 21f contained in the nonwoven fabric 20 may form a single fiber group made of one type of fiber, or may form a mixed fiber group that is a mixture of a fiber group made of one type of fiber and a fiber group made of another type of fiber. In other words, the multiple first fibers 21f contained in the nonwoven fabric 20 may be the same fiber, or may be multiple types of fibers.

[0027] Specific examples of the first resin 21 include thermoplastic resins such as polyolefin resins, polyester resins, and polyurethane resins. Examples of the polyolefin resin include polypropylene resin and polyethylene resin. Examples of the polyester resin include polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate. The first resin 21 may be one type of resin selected from the resins exemplified above, or may be a mixed resin in which two or more types are combined.

[0028] The melting point of the first resin 21 is higher than the melting point of the second resin 22 and the melting point of the third resin 31. From the viewpoint of effectively avoiding melting of the first resin 21 when the third resin 31 is melted to form the adhesive part 30, the melting point of the first resin 21 is preferably higher than the melting point of the second resin 22 by 20° C. or more, more preferably by 30° C. or more, and even more preferably by 40° C. or more. For example, first resin 21 preferably has a melting point of 190°C or more and 230°C or less, and more preferably is a polyester-based resin having a melting point of 190°C or more and 230°C or less.

[0029] Second fiber, second resin: The second fibers 22f are composed of the second resin 22. In the laminated sheet 100, the second resin 22 is a resin having a melting point lower than that of the first resin 21 and the third resin, specifically selected from resins having a melting point of 100°C or more and 120°C or less. This makes it possible to melt only the second fibers 22f without melting the first fibers 21f and the adhesive portion 30 due to the heating temperature during the heat press processing when the laminated sheet 100 is bonded to a core material or the like by heat press processing to create a processed body. By melting the second fibers 22f while maintaining the first fibers 21f in a fibrous state in the nonwoven fabric 20, the first fibers 21f are bonded to each other by the second resin 22, and the nonwoven fabric 20 is tightened to exhibit good smoothness.

[0030] The second resin 22 may be any resin that satisfies the above-mentioned melting point condition, and may be composed of one type of resin or a mixed resin containing two or more types of resin. When the second resin 22 is composed of a mixed resin, the melting point of the mixed material may be lower than the melting points of the first resin 21 and the third resin 31, and may be 100°C or higher and 120°C or lower.

[0031] In addition, within the range satisfying the relationship of formula (1) and the melting point range of the second resin, the second fibers 22f contained in the nonwoven fabric 20 may form a single fiber group made of one type of fiber, or may form a mixed fiber group that is a mixture of a fiber group made of one type of fiber and a fiber group made of another type of fiber. In other words, the multiple second fibers 22f contained in the nonwoven fabric 20 may be the same fiber, or may be multiple types of fibers.

[0032] Specific examples of the second resin 22 include polyolefin-based resins, polyester-based resins, and polyurethane-based resins. Examples of the polyolefin resin include polypropylene resin and polyethylene resin. Examples of the polyester resin include polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate. The second resin 22 may be one type of resin selected from the resins exemplified above, or may be a mixed resin in which two or more types are combined.

[0033] The second resin 22 may be a resin different from the first resin 21, or may be the same type of resin. In the present invention, the term "same type of resin" means that the base resin contained in the resin at more than 50% by mass is the same resin component. For example, one polyethylene terephthalate resin and another polyethylene terephthalate resin are the same type of resin when, in 100% by mass of each resin, more than 50% by mass of a polyethylene terephthalate component and another resin are contained, and the content of the polyethylene terephthalate component is different and / or the type of resin contained other than polyethylene terephthalate is different. Alternatively, when one polyethylene terephthalate resin is polyethylene terephthalate and the other resin contains more than 50% by mass of a polyethylene terephthalate component and another resin in 100% by mass of the resin, these resins are also determined to be the same type of resin.

[0034] From the viewpoint of recyclability, it is preferable that second resin 22 is the same type of resin as first resin 21, and it is more preferable that first resin 21 and second resin 22 are both polyester-based resins. If first resin 21 and second resin 22 are both polyester-based resins, they will blend well with skin 10, and nonwoven fabric 20 will have good smoothness during hot press processing, which will be described later.

[0035] The content of the first fibers 21f and the second fibers 22f in the nonwoven fabric 20 is not particularly limited, but from the viewpoint of ensuring sufficient gaps between the first fibers 21f while bonding the first fibers 21f together with the molten second fibers 22f when hot pressing is performed using the laminated sheet 100 to maintain a good feel and flexibility of the nonwoven fabric, the content by mass of the second fibers 22f in 100% by mass of the resin fibers constituting the nonwoven fabric 20 is preferably less than 50% by mass, more preferably 40% by mass or less, and even more preferably 30% by mass or less. In particular, in the laminate sheet 100 used as a skin material for automobile interior parts, and railway car and aircraft interior parts, which have strict regulations for flame retardancy, the content of the second fibers 22f in 100 mass% of the resin fibers constituting the nonwoven fabric 20 is preferably in the range of 2 mass% or more and 30 mass% or less, more preferably 3 mass% or more and 15 mass% or less, and even more preferably 3 mass% or more and 7 mass% or less. The above-described preferable range of the content of the second fibers 22f in the nonwoven fabric 20 is also applicable to an embodiment in which the resin fibers constituting the nonwoven fabric 20 are made of the first fibers 21f and the second fibers 22f.

[0036] <Adhesive part> The adhesive portion 30 contains a third resin 31, and adheres and laminates the skin 10 and the nonwoven fabric 20. When the cross section of the laminated sheet 100 is observed with a stereomicroscope at a magnification of 50 times, the adhesive portion 30 may be formed in a scattered manner at the interface between the skin 10 and the nonwoven fabric 20 as shown in FIG. 1, or may be formed in a completely continuous single layer or a substantially continuous layer at the interface between the skin 10 and the nonwoven fabric 20 as shown in FIG. 2. From the viewpoint of exhibiting better flexibility in the laminated sheet 100, the adhesive portion 30 is preferably formed in a scattered manner at the interface between the skin 10 and the nonwoven fabric 20. On the other hand, from the viewpoint of better adhesion between the skin 10 and the nonwoven fabric 20 and from the viewpoint of smoothness in the laminated sheet 100, the adhesive portion 30 is preferably formed in a layer at the interface between the skin 10 and the nonwoven fabric 20. The third resin 31 may be any resin that satisfies the condition of the above-mentioned formula (1), and may be composed of one type of resin or two or more types of resins. From the viewpoint of increasing the stiffness of the laminate sheet 100, the third resin 31 is preferably a polypropylene-based resin.

[0037] The melting point of the third resin 31 satisfies the condition of the above formula (1) and is preferably 120° C. or more and 200° C. or less. In particular, it is preferable that the melting point of the first resin 21 is 190° C. or more and 230° C. or less, the melting point of the second resin is 100° C. or more and 120° C. or less, and the melting point of the third resin 31 is 120° C. or more and 200° C. or less, while satisfying the condition of the above formula (1).

[0038] When the environment in which the processed body having the laminated sheet 100 as a skin material is used is expected to be high temperature, the melting point of the third resin 31 is preferably 125° C. or higher, more preferably 135° C. or higher, and even more preferably 150° C. or higher. For example, when the processed body is expected to be used for a vehicle ceiling or the like, the skin 10 of the processed body faces downward, so it is preferable to take care that the third resin 31 does not melt and droop even if the vehicle body temperature becomes high. Therefore, as described above, the melting point of the third resin 31 is preferably 125° C. or higher. Furthermore, although the melting point of the second resin 21 is lower than the melting point of the third resin 31, by making the content of the second resin 21 in the nonwoven fabric 20 between 3% by mass and 7% by mass, it is possible to suppress sagging at high temperatures while improving the bonding between the first fibers 21f and thereby effectively tighten the nonwoven fabric 20.

[0039] Furthermore, when manufacturing the laminated sheet 100 by frame lamination, which will be described later, if the melting point of the third resin 31 is too high, it may be difficult to melt it with a flame, or there is a risk that the first fibers 21f and / or the second fibers 22f may melt along with the melting of the third resin 31. From the viewpoint of selectively and satisfactorily melting the third resin 31 in carrying out the frame lamination, the melting point of the third resin 31 is preferably 190° C. or lower, and more preferably 180° C. or lower.

[0040] Although the laminated sheet 100 including the surface skin 10, the nonwoven fabric 20, and the adhesive part 30 that bonds and laminates them has been described above, the laminated sheet of the present invention is not limited to such description and may include any laminated layer other than the surface skin 10 and the nonwoven fabric 20. For example, a backing layer or the like may be further provided on the surface of the nonwoven fabric 20 opposite the surface skin 10.

[0041] The above-mentioned specific examples of the first resin 21 are appropriately referred to as the third resin 31. The third resin 31 may be a resin different from the first resin 21 or may be the same type of resin as the first resin 21. Similarly, the third resin 31 may be a resin different from the second resin 22 or may be the same type of resin as the second resin 22.

[0042] <Recyclability> Unlike conventional laminate sheets that use a polyurethane foam sheet as a substrate, the laminate sheet 100 uses a nonwoven fabric 20 as a substrate. Therefore, it is possible to select a resin other than a polyurethane-based resin as the resin constituting the nonwoven fabric 20. Although recycling of polyurethane resins at the manufacturing and processing stages has been put into practical use, material recycling from used products has not yet been put into practical use. Material recycling here refers to separating and processing specific materials from waste and reusing them as raw materials for new products. In view of these circumstances, according to an embodiment of the present invention in which the nonwoven fabric 20 is made of a resin other than a polyurethane-based resin, it is possible to separate the nonwoven fabric 20 from the used laminated sheet 100, thereby facilitating material recycling.

[0043] From the viewpoint of promoting material recycling more effectively, it is preferable that the first resin 21 and the second resin 22 are the same type of resin in the laminate sheet 100. With the laminate sheet 100 of this embodiment, it is possible to peel off and separate the skin 10 and the nonwoven fabric 20, and promote material recycling of the nonwoven fabric 20. In particular, from the viewpoint of recycling technology being industrially established and promoting material recycling effectively, it is preferable that the first resin 21 and the second resin 22 are both polyester-based resins, and it is more preferable that the first resin 21 and the second resin 22 are both polyethylene terephthalate-based resins.

[0044] From the viewpoint of being able to provide recycled materials with higher purity by material recycling, it is preferable that the first resin 21, the second resin 22, and the third resin 31 are all the same type of resin. This makes it possible to provide recycled resin materials with high purity even if part or all of the adhesive portion 30 (third resin 31) remains on the nonwoven fabric 20 when the skin 10 and the nonwoven fabric 20 are peeled away from each other. Among these, it is more preferable that the first resin 21, the second resin 22, and the third resin 31 are all polyester-based resins, and it is even more preferable that the first resin 21, the second resin 22, and the third resin 31 are all polyethylene terephthalate-based resins. From the viewpoint of being able to provide recycled resin with higher purity, it is particularly preferable that the nonwoven fabric 20 peeled off from the skin 10 does not contain any resin other than the first resin 21, the second resin 22 and the third resin 31, which are all of the same type.

[0045] Furthermore, by unifying all the resins constituting the laminate sheet 100 with the same type of resin, it is possible to make the laminate sheet 100 a mono-material. The mono-material laminate sheet 100 does not require a sorting process for separating the surface layer 10 and the nonwoven fabric 20, and can be provided to a recycling process. Among these, it is more preferable that the skin 10, the nonwoven fabric 20 and the adhesive portion 30 are all made of a polyester-based resin, and it is even more preferable that the skin 10, the nonwoven fabric 20 and the adhesive portion 30 are all made of a polyethylene terephthalate-based resin.

[0046] <Frame laminated sheet> One of the features of the laminated sheet 100 is that the second fibers 22f having a lower melting point than the third resin 31 maintain their fibrous form while the third resin 31 melts to form the adhesive portion 30. That is, in the laminated sheet 100 alone before being used for hot press processing or the like, the unmelted fibrous second fibers 22f and the adhesive portion 30 formed by melting the third resin 31 having a higher melting point than the second resin 22 coexist. The present invention encompasses an embodiment in which the molten second resin 22 and the fibrous second resin 22 (i.e., second fibers 22f) coexist in the nonwoven fabric 20 of the laminate sheet 100. However, from the viewpoint of favorably shaping the laminate sheet 100 on the surface of the core material or the like while favorably tightening and smoothing the laminate sheet 100 when the laminate sheet 100 is used as a skin material of the core material or the like and performing heat press processing, the fibrous second resin 22 (second fibers 22f) is preferably 70 mass% or more, more preferably 80 mass% or more, and even more preferably 90 mass% or more of the total amount (100 mass%) of the second resin 22 in the nonwoven fabric 20.

[0047] The method for manufacturing the laminate sheet 100 having such characteristics is not particularly limited, but for example, in a thermal lamination process or a hot melt lamination process that is commonly used as a method for manufacturing a laminate sheet, the entire laminate sheet is heated during heating, and when the third resin 31 melts to form the adhesive portion 30, the second fibers 22f made of the second resin 22, which has a relatively low melting point, are likely to melt as well, making it difficult to adjust the temperature. Therefore, a laminate sheet manufactured by the above-mentioned commonly used lamination process is likely to contain a large amount of non-fibrous second resin 22 formed by melting the second fibers 22f. In this specification, the terms "thermal lamination" and "hot melt lamination" refer to a processing method in which a laminate having an adhesive resin disposed between a first layer and a second layer is heated as a whole while being appropriately pressed in the thickness direction to melt the adhesive resin and bond the first layer and the second layer together.

[0048] According to the inventors' research, after considering a means for melting the third resin 31 to form the adhesive portion 30 while leaving the second fibers 22f in the nonwoven fabric 20, they arrived at the application of frame lamination processing, which is conventionally known as a lamination method for laminated sheets using polyurethane foam sheets, as one of the means for manufacturing the laminated sheet 100.

[0049] Frame lamination is generally known as a method of melting the surface of a polyurethane foam sheet by heating with a flame, and laminating any other sheet in that state to laminate and bond them together. In contrast, the present invention provides a laminated sheet 100 in which, as shown in FIG. 3, a pre-sheet 110 described below is used instead of a polyurethane foam sheet, and the surface on which the third resin 31 is arranged is heated with a flame 440 while the pre-sheet 110 is conveyed to melt it, and in that state, the pre-sheet 110 is laminated with the skin 10, and the nonwoven fabric 20 and the skin 10 are laminated and bonded together via the adhesive part 30 made of the molten third resin 31. Since such frame lamination can selectively heat only a specific surface with a flame, rather than the entire pre-sheet 110, it is possible to melt the third resin 31 without melting the second fiber 22f in the nonwoven fabric 20 by adjusting the temperature of the flame, the distance between the flame and the surface (i.e., the surface on which the third resin 31 is arranged), and the conveying speed of the pre-sheet 110, etc. In other words, the present invention encompasses an embodiment of a laminated sheet 100 in which a pre-sheet 110 (see Figures 4 and 5) having a layer containing nonwoven fabric 20 and a third resin 31 laminated on one side of the nonwoven fabric 20 and a skin 10 are bonded and laminated by frame lamination processing.

[0050] As the pre-sheet 110 used in the frame lamination process described above, for example, as shown in FIG. 4A, a pre-sheet 110A (see FIG. 4B) which is a nonwoven fabric in which a fiber layer 114 including the first fiber 21f and the second fiber 22f and a fiber layer 112 including the third fiber 31f made of the third resin 31 are stacked and integrated by needle punching can be used. The fiber layer 114 in the pre-sheet 110A corresponds to the nonwoven fabric 20, and the fiber layer 112 integrated on the fiber layer 114 is a layer including the third resin. The pre-sheet 110A is a sheet of nonwoven fabric created by entangling the fibers of the fiber layer 112 and the fiber layer 114 with each other by needle punching. Therefore, the fibers of the fiber layer 112 and the fiber layer 114 in the pre-sheet 110A may be in a state where they are intertwined with each other at the interface between them.

[0051] The pre-sheet 110A produced by needle punching has an advantage that the basis weight can be easily adjusted. In addition, the pre-sheet 110A has good handleability because the nonwoven fabric 20 and the third fiber 31f made of the third resin 31 are integrated into a single sheet.

[0052] As another embodiment of the pre-sheet 110 used in the frame lamination process described above, for example, as shown in Fig. 5A, a pre-sheet 110B (see Fig. 5B) which is a multi-layer sheet in which a nonwoven fabric 20 including a first fiber 21f and a second fiber 22f and a sheet 122 including a third resin 31 are stacked on each other can be used. In this case, in order to facilitate handling during the frame lamination process, the nonwoven fabric 20 and the sheet 122 may be stacked in advance by any method to such an extent that their relative positions do not shift, and their relative positions may be fixed. Examples of the fixing method include, but are not limited to, temporary fixing using an adhesive member and temporary fixing by needle punching.

[0053] In the pre-sheet 110B, the third resin 31 (sheet 122) which has been previously formed into a sheet is laminated on the nonwoven fabric 20, so that the third resin 31 can be easily arranged evenly on one surface of the nonwoven fabric 20. The nonwoven fabric 20 in the pre-sheet 110B may be manufactured by a method appropriately selected from known nonwoven fabric manufacturing methods, such as a needle punch method or a spun lace method. By selecting the needle punch method as the manufacturing method for the nonwoven fabric 20, it is easy to greatly adjust the basis weight of the nonwoven fabric 20. Furthermore, by selecting the spun lace method as the manufacturing method for the nonwoven fabric 20, it is possible to increase the production speed compared to the needle punch method, and it is also possible to manufacture a nonwoven fabric 20 with good smoothness. The sheet 122 in the pre-sheet 110B may be a continuous resin sheet, or may be a nonwoven fabric sheet containing the third fibers 31f.

[0054] [Laminated sheet manufacturing method] The method for producing a laminated sheet of the present invention using frame lamination will be described in more detail below, although the method for producing a laminated sheet of the present invention is not limited to the method for producing a laminated sheet of the present invention.

[0055] The laminated sheet manufacturing method of the present invention uses a nonwoven fabric 20 including a first fiber 21f made of a first resin 21 and a second fiber 22f made of a second resin 22 having a melting point lower than that of the first resin 21, and a pre-sheet 110 having a layer including a third resin 31 laminated on one side of the nonwoven fabric 20, and laminates and bonds the nonwoven fabric 20 and the skin 10 by frame lamination. More specifically, as shown in FIG. 3, the pre-sheet 110 is set on a roll 410 and transported at an appropriate speed, and the skin 10 is set on a roll 420 and transported at an appropriate speed. A melting step is performed upstream of where the pre-sheet 110 and the skin 10 are laminated, in which the third resin 31 is melted by a flame 440. A plurality of fire holes from which the flame 440 is ejected may be arranged at appropriate intervals in the width direction of the pre-sheet 110 (into the paper surface of FIG. 3). Then, a lamination step is performed in which the skin 10 is laminated on the nonwoven fabric 20 via the third resin 31 melted in the melting step, and an adhesive part forming step is performed in which an adhesive part 30 containing the third resin 31 is formed between the nonwoven fabric 20 and the skin 10, thereby producing a laminated sheet 100. Note that the lamination step and the adhesive part forming step described above may be performed in part or in whole overlapping with each other.

[0056] In this manufacturing method, by adjusting one or more conditions such as the conveying speed of the pre-sheet 110 and the skin 10, the number and spacing of the nozzles of the flame 440, the distance between the flame 440 and the pre-sheet 110, the blending ratio of the third fiber in the pre-sheet 110, and the composition of the third resin that constitutes the third fiber, it is possible to produce a dotted adhesive portion 30 as shown in FIG. 1 or a layered adhesive portion 30 as shown in FIG. 2. The conveying speed of the pre-sheet 110 and the skin 10 in this manufacturing method is not particularly limited, but from the viewpoint of melting the third resin 31 well without melting the second fibers 22f, it is preferable to adjust it in the range of 15 m / min to 35 m / min. The temperature of the flame 440 is not particularly limited, but it is preferable to adjust it in the range of about 600° C. to 800° C. The distance between the surface of the pre-sheet 110 on the bonding portion 30 side and the flame 440 is preferable to adjust appropriately taking into consideration the type and melting point of the resin constituting the pre-sheet 110.

[0057] According to the manufacturing method of the laminated sheet 100 by the above-mentioned frame lamination process, the third resin 31 can be selectively heated by the flame 440, so that it is possible to form the adhesive portion 30 without melting the second fibers 22f in the nonwoven fabric 20.

[0058] (Pre-sheet 110A) The pre-sheet 110 used in the above-described manufacturing method may be, for example, a pre-sheet 110A shown in Fig. 4B. The pre-sheet 110A is a nonwoven fabric sheet (see Fig. 4B) obtained by laminating and integrating a fiber layer 114 including the first fibers 21f and the second fibers 22f and a fiber layer 112 including the third fibers 31f shown in Fig. 4A in an overlapping state by needle punching. The pre-sheet 110A has good handleability because the nonwoven fabric 20 and the third fibers 31f are laminated and integrated by the needle punch method, and the basis weight can be easily adjusted. By using the pre-sheet 110A having a large basis weight, the basis weight of the obtained laminated sheet 100 can be made large, and it is easy to provide a flexible laminated sheet 100.

[0059] (Pre-sheet 110B) As another example of the pre-sheet 110 used in the above-described manufacturing method, for example, a pre-sheet 110B shown in FIG. 5B can be used. The pre-sheet 110B is a multi-layer sheet obtained by preparing and overlapping a nonwoven fabric 20 including the first fibers 21f and the second fibers 22f shown in FIG. 5A and a sheet 122 including the third resin 31. In the pre-sheet 110B, the nonwoven fabric 20 and the sheet 112 may simply be overlapped, but in order to facilitate handling during frame lamination processing, the nonwoven fabric 20 and the sheet 122 may be laminated in advance by any method to such an extent that their relative positions do not shift, and their relative positions may be fixed. Examples of the fixing method include, but are not limited to, temporary fixing using an adhesive member and temporary fixing by needle punching.

[0060] <Average fiber length and average fiber diameter of fibers used in the composition of nonwoven fabric> The average fiber diameter and the average fiber length of each of the first fibers 21f, the second fibers 22f, and the third fibers 31f used to manufacture the laminate sheet 100 are not particularly limited. In addition, in the drawings, an embodiment in which the fiber length of the second fibers 22f is shorter than the fiber length of the first fibers 21f is illustrated, but this is merely an example and does not limit the present invention. In addition, when the third fibers 31f are used to form the adhesive portion 30, the smaller the average fiber length and average fiber diameter of the third fibers 31f, the easier it is to melt the third fibers 31f in a short time during frame lamination processing, and to easily prevent the second fibers 22f from melting due to the heat of melting.

[0061] The laminate sheet of the present invention described above may be configured by appropriately combining the respective configurations described as the first embodiment without departing from the spirit of the present invention. For example, as a more specific example of the laminate sheet of the present invention, a fiber layer 114 is prepared by mixing first fibers 21f (95% by mass) made of polyethylene terephthalate resin having a melting point of 210°C, having an average fiber length of 50 mm, and an average fiber diameter of 4 denier, and second resin 22f (5% by mass) made of polyethylene terephthalate resin having a melting point of 110°C, having an average fiber length of 50 mm, and an average fiber diameter of 4 denier. A pre-sheet 110A (basis weight 150 g / m) is a nonwoven fabric that is laminated and integrated by needle punching in a state in which a third fiber 31f made of a polyethylene terephthalate resin having a melting point of 150° C. and an average fiber length of 50 mm and an average fiber diameter of 4 denier is layered on the fiber layer 114. 2 ) to prepare. The skin 10 is a knitted fabric (100 g / m2) made of PET fibers spun using a polyethylene terephthalate resin. 2 )do. Then, by frame lamination, while conveying the pre-sheet 110A, the third fibers 31f side is heated by a flame 440 to selectively melt the third fibers 31f, and the skin 10 is quickly laminated and bonded, thereby obtaining the laminated sheet 100. By heat-pressing the laminated sheet 100 against the surface of any core layer, a processed body with good appearance can be provided.

[0062] Different specific examples of the laminate sheet of the present invention are as follows. A nonwoven fabric 20 (basis weight 150 g / m) manufactured by a needle punch method using a first fiber 21f (95% by mass) having an average fiber length of 50 mm and an average fiber diameter of 4 denier made of a polyethylene terephthalate resin having a melting point of 210° C. and a second fiber 22f (5% by mass) having an average fiber length of 50 mm and an average fiber diameter of 4 denier made of a polyethylene terephthalate resin having a melting point of 110° C. 2 ) to prepare. A sheet 122 (basis weight 20 g / m) made of nonwoven fabric by a spunlace method using third fibers 31f having an average fiber length of 50 mm and an average fiber diameter of 4 denier, which are made of a polypropylene-based resin having a melting point of 120°C. 2 Then, the sheet 122 is superimposed on the nonwoven fabric 20 described above, and the pre-sheet 110B is prepared by laminating the sheets by needle punching to such an extent that the relative positions of the sheets do not shift. The skin 10 is a knitted fabric (100 g / m2) made of PET fibers spun using a polyethylene terephthalate resin. 2 )do. Then, by frame lamination, while conveying the pre-sheet 110B, the sheet 122 side is heated by a flame 440 to selectively melt the third fibers 31f, and the skin 10 is quickly laminated and bonded, thereby obtaining the laminated sheet 100. By heat-pressing the laminated sheet 100 against the surface of any core layer, a processed body with good appearance can be provided. In addition, in both the laminated sheet using the pre-sheet 110A specifically described above and the laminated sheet using the pre-sheet 110B, a woven fabric, a nonwoven fabric, a synthetic leather, or the like can be used instead of the knitted fabric skin 10. For example, when synthetic leather is used instead of the knitted fabric skin 10, synthetic leather having a resin layer such as a vinyl chloride resin layer formed on one side of a base fabric can also be used as the skin 10. In this case, the base fabric and the nonwoven fabric 20 are laminated and bonded to each other with the orientation facing each other.

[0063] [Heat-pressed body] The laminated sheet 100 described above is preferably used as a skin material for a core material or the like. For example, as shown in FIG. 6, a processed body 200 can be provided by pressing the laminated sheet 100 against one side of a core material 210 of a desired shape by heat pressing. In the laminated sheet 100 in the processed body 200, the second fibers 22f blended in the nonwoven fabric 20 constituting the laminated sheet 100 are melted by the heat during heat pressing, and the surrounding first fibers 21f are bonded. As a result, the smoothness of the nonwoven fabric 20 is improved, and as a result, the appearance of pockmarks caused by the nonwoven fabric 20 on the surface of the epidermis 10 is prevented. Therefore, when visually observed from the laminated sheet 100 side, the processed body 200 is provided with no unevenness and an excellent appearance. In addition, the laminated sheet 100 side of the processed body 200 has an excellent appearance and can be given the good feel and flexibility of the nonwoven fabric 20.

[0064] The present invention described above encompasses the following technical ideas. (1) the epidermis; A nonwoven fabric, The nonwoven fabric includes first fibers made of a first resin and second fibers made of a second resin having a melting point lower than that of the first resin, the skin and the nonwoven fabric are laminated by being bonded together at an adhesive portion containing a third resin, The melting point of the second resin is 100° C. or more and 120° C. or less, and The melting points of the first resin, the second resin, and the third resin are related by the following formula (1): [Formula 3] Melting point of second resin < melting point of third resin < melting point of first resin... (1) A laminated sheet characterized by: (2) The laminate sheet according to (1) above, wherein the second resin is contained in an amount of 2% by mass or more and 30% by mass or less, relative to 100% by mass of the nonwoven fabric. (3) The laminate sheet according to (1) or (2) above, which is a laminate sheet for hot press processing that is laminated onto the surface of a core material by hot press processing. (4) A laminate sheet according to any one of (1) to (3) above, in which a pre-sheet having a layer containing the nonwoven fabric and the third resin laminated on one side of the nonwoven fabric and the skin are bonded and laminated by frame lamination. (5) The laminate sheet according to the above (4), wherein the pre-sheet is a nonwoven fabric sheet in which a fiber layer containing the first fibers and the second fibers and a fiber layer containing third fibers made of the third resin are laminated together by needle punching in an overlapping state. (6) The laminate sheet according to (4) above, wherein the pre-sheet is a multi-layer sheet in which a nonwoven fabric containing the first fibers and the second fibers and a sheet containing the third resin are laminated. (7) The laminate sheet according to any one of (1) to (6) above, wherein the first resin and the second resin are polyester-based resins. (8) The laminate sheet according to (7) above, wherein the third resin is a polyester-based resin. (9) The laminate sheet according to any one of (1) to (8) above, wherein the skin, the nonwoven fabric and the adhesive portion are all made of a polyester-based resin. (10) A pre-sheet is used in which a nonwoven fabric includes first fibers made of a first resin and second fibers made of a second resin having a melting point lower than that of the first resin, and a layer containing a third resin is laminated on one side of the nonwoven fabric, Frame lamination processing, a melting step of melting the third resin; a lamination step of laminating a surface layer onto the nonwoven fabric including the first fibers and the second fibers via the third resin melted in the melting step; an adhesive portion forming step of forming an adhesive portion containing the third resin between the nonwoven fabric and the skin; A method for producing a laminate sheet, comprising carrying out the steps of: (11) The laminate sheet according to the above (10), wherein the pre-sheet is a nonwoven fabric sheet in which a fiber layer containing the first fibers and the second fibers and a fiber layer containing the third fibers are laminated together by needle punching in an overlapping state. (12) The laminate sheet according to (10) above, wherein the pre-sheet is a multilayer sheet in which a nonwoven fabric containing the first fibers and the second fibers and a sheet containing the third resin are laminated. [Explanation of symbols]

[0065] 10...epidermis 20...Nonwoven fabric 21...Daiichi Resin 21f: First Fiber 22...Second resin 22f...Second fiber 30...Adhesive part 31...Third resin 31f...Third fiber 100···Laminated sheet 110···Pre-sheet 110A···First pre-sheet 110B...Second pre-sheet 112...Fiber layer 114...Fiber layer 122... sheets 200...processed body 210 Core material 410...First roll 420...Second roll 430...Third roll 440...Flame

Claims

1. The epidermis and A nonwoven fabric, The nonwoven fabric includes first fibers made of a first resin and second fibers made of a second resin having a melting point lower than that of the first resin, the skin and the nonwoven fabric are laminated by being bonded together at an adhesive portion containing a third resin, The melting point of the second resin is 100° C. or more and 120° C. or less, and The melting points of the first resin, the second resin, and the third resin are related by the following formula (1): [Formula 1] Melting point of second resin < melting point of third resin < melting point of first resin ... (1) A laminated sheet characterized by:

2. 2. The laminate sheet according to claim 1, which is a laminate sheet for hot press processing that is laminated onto the surface of a core material by hot press processing.

3. 3. The laminate sheet according to claim 1, wherein the first resin and the second resin are polyester resins.

4. 3. The laminate sheet according to claim 1, wherein a pre-sheet having the nonwoven fabric and a layer containing the third resin laminated on one side of the nonwoven fabric and the skin are bonded and laminated by frame lamination.

5. 5. The laminate sheet according to claim 4, wherein the pre-sheet is a nonwoven fabric sheet in which a fiber layer containing the first fibers and the second fibers and a fiber layer containing third fibers made of the third resin are laminated together by needle punching in an overlapping state.

6. The laminate sheet according to claim 4 , wherein the pre-sheet is a multi-layer sheet in which a nonwoven fabric containing the first fibers and the second fibers and a sheet containing the third resin are laminated.

Images