JP6691913B2 - Embossing composites and embossed products - Google Patents

Description

  Embodiments of the present invention relate to embossing composites and embossed articles.

  BACKGROUND ART Today, as a vehicle interior material or a surface material for a chair, a composite material in which a soft polyurethane foam sheet and a surface material such as knitted cloth, woven cloth, non-woven cloth, synthetic leather or artificial leather are laminated is used. In order to improve the designability of such a composite material, an uneven design may be formed on the surface. For example, the surface of a composite material has been embossed in order to impart an uneven design. However, the flexible polyurethane foam sheets that make up the composite are elastic. Therefore, even if heating and pressing are performed by embossing, if the design is a fine uneven shape, due to the compression recovery force due to the elasticity of the flexible polyurethane foam sheet, there is a problem that sufficient shaping effect can not be obtained. is there.

  For example, Patent Document 1 discloses a method of processing a skin material, in which a thick flexible polyurethane foam is laminated to form a deep uneven pattern, with an embossing device having a heat roll. However, it cannot be said that the depth of the uneven pattern and the cushioning property are compatible with each other.

Japanese Patent Laid-Open No. 2007-276285

  An embodiment of the present invention solves the above-mentioned problems and provides an embossed product in which a deep uneven design is formed and which is also excellent in uneven design shapeability and cushioning property.

  An embodiment of the present invention is an embossing composite material in which a first flexible polyurethane foam sheet and a second flexible polyurethane foam sheet are laminated in this order on the back surface of a skin material, and the first flexible polyurethane foam sheet is The embossing composite material has a softening point higher than that of the second flexible polyurethane foam sheet.

  Also, an embodiment of the present invention is an embossed product in which the surface of the skin material of the composite material for embossing is embossed.

  According to the embodiment of the present invention, it is possible to provide an embossed product in which a deep concave-convex design is formed and which has excellent concave-convex design shapeability and cushioning properties.

It is sectional drawing of the composite material for embossing which shows one Example of this invention. It is sectional drawing of the composite material for embossing which shows another Example of this invention. It is sectional drawing of the embossing product which concerns on one Example.

  Hereinafter, embodiments of the present invention will be described in detail.

  One embodiment of the present invention is an embossing composite material in which a first flexible polyurethane foam sheet and a second flexible polyurethane foam sheet are sequentially laminated on a back surface of a skin material, and the first flexible polyurethane foam sheet is , A composite material for embossing having a higher softening point than the second flexible polyurethane foam sheet. When embossing is performed using the embossing composite material having such a configuration, a deep embossed design is formed, and an embossed product having excellent embossing designability and cushioning properties can be obtained. Here, the back (back) surface of the skin material is a surface opposite to the front (front) surface to which embossing is applied, and is also referred to as a lower surface.

  The cross-sectional view of the composite material 5 for embossing shown in FIG. 1 is an example of a laminated state of the skin material 1, the first flexible polyurethane foam sheet 2, and the second flexible polyurethane foam sheet 3. In this example, the back cloth 4 is laminated on the back surface of the second flexible polyurethane foam sheet 3.

  The skin material used in this embodiment is not particularly limited, and examples thereof include woven fabric, knitted fabric, nonwoven fabric, and leather. A complex composed of two or more of these may be used. Examples of the leather include synthetic leather, artificial leather, and natural leather.

  As the skin material, a material containing fibers as its constituent elements is preferably used. The fiber material forming the skin material is not particularly limited, and thermoplastic fibers are preferable from the viewpoint of the moldability and durability of the uneven design. Examples of the thermoplastic fibers include synthetic fibers such as polyester, polypropylene and nylon, and semi-synthetic fibers such as acetate and triacetate. These may be used alone or in combination of two or more. Of these, synthetic fibers are more preferable, polyester fibers are more preferable, and polyethylene terephthalate fibers are particularly preferable, because they are excellent in physical properties, particularly strength, abrasion resistance, and heat resistance. The fiber material is preferably composed mainly of thermoplastic fibers, but within a range that does not affect the physical properties, fibers other than thermoplastic fibers, for example, fibers such as natural fibers and recycled fibers are mixed and mixed. It may be a combination of methods such as fiber, mixed twist, mixed weave, and mixed knitting.

  The single fiber fineness of the fibers constituting the surface material is preferably mainly 1.5 dtex or less. When the monofilament fineness is 1.5 dtex or less, the imprintability of fine unevenness due to embossing is further improved. Further, the single fiber fineness is preferably 0.03 dtex or more in terms of abrasion resistance.

  The form of the yarn may be either a short fiber yarn such as a spun yarn or a long fiber yarn such as a multifilament yarn or a monofilament yarn, and further, a long-short composite spun yarn in which long fibers and short fibers are combined. Good. The multifilament yarn may be twisted as necessary, or may be subjected to processing such as false twisting processing or liquid disturbance processing.

  Such a skin material is used for the composite material of the present embodiment after undergoing a pretreatment such as presetting and scouring or a coloring step, if necessary.

  The thickness of the skin material is preferably in the range of 0.5 to 3.0 mm in terms of the imprintability of a concavo-convex design, wear resistance and the like.

  The flexible polyurethane foam sheet used in the present embodiment is a sheet of soft foamed synthetic rubber in which foamed bubbles are communicated with a polyol and a polyisocyanate as main components and a foaming agent or the like is mixed to form a resin. As the flexible polyurethane foam sheet, for example, a continuous sheet produced by soft slab foaming and sliced in the longitudinal direction to form a long sheet can be used.

  At least two types of flexible polyurethane foam sheets are used, and the first flexible polyurethane foam sheet and the second flexible polyurethane foam sheet are laminated. The first flexible polyurethane foam sheet has a higher softening point than the second flexible polyurethane foam sheet. The softening point is a temperature at which a rapid displacement due to softening of the sample starts when a temperature is applied by applying a load to the sample using a thermomechanical analysis (TMA) device and a probe for expansion measurement with a flat tip. And

  In this embodiment, at least two types of flexible polyurethane foams having different characteristics are used as the flexible polyurethane foam sheets to be laminated. As shown in FIG. 1, a first flexible polyurethane foam sheet 2 is installed in a lower layer located on the back surface side of a skin material 1 which is an embossed side, and a second flexible polyurethane foam sheet is provided in a layer below the first flexible polyurethane foam sheet 2. Install 3. With such a configuration, the second flexible polyurethane foam sheet 3 having a low softening point is largely shaped at the time of embossing and is easily fused by the heat at the time of embossing, so that an uneven design can be efficiently formed. Is possible. Furthermore, since the first soft polyurethane foam sheet 2 having a high softening point has little influence on the peripheral portion of the embossed portion due to heat during embossing, the thickness can be maintained and the cushioning property which is a characteristic of the flexible polyurethane foam can be maintained. ..

  The softening point of the first flexible polyurethane foam sheet 2 is preferably 150 ° C to 200 ° C. The softening point of the second flexible polyurethane foam sheet 3 is preferably 90 ° C to 110 ° C.

  Further, the first flexible polyurethane foam sheet 2 and the second flexible polyurethane foam sheet 3 preferably have a compressibility of 40% to 60% at a temperature 30 ° C. higher than their respective softening points. As a result, the flexible polyurethane foam sheet is easily shaped during embossing, so that a deep uneven design can be formed.

Here, the compressibility at a temperature 30 ° C. higher than each softening point is calculated as follows by measuring the thickness of the flexible polyurethane foam at each temperature when measuring the softening point by the above-mentioned TMA measurement.
Compressibility (%) = thickness at a temperature 30 ° C. higher than the softening point of the flexible polyurethane foam sheet (mm) ÷ thickness of the flexible polyurethane foam sheet before heating (mm) × 100

  The total thickness of the laminated first flexible polyurethane foam sheet 2 and second flexible polyurethane foam sheet 3 is preferably 3.0 mm to 15 mm. Within this range, the embossed portion is heat-sealed and closely adhered during embossing, and the thickness of the soft urethane foam sheet is maintained in the non-embossed portion, so that a deeper uneven design can be formed. .. The "total thickness" here is the total thickness of a plurality of flexible polyurethane foam sheets laminated on the back surface of the skin material.

  The thickness of the first flexible polyurethane foam sheet is preferably 2.0 to 7.0 mm, more preferably 3.0 to 5.0 mm. When the thickness is 2.0 mm or more, the cushioning property can be maintained. When the thickness is 7.0 mm or less, the shapeability of the uneven design by embossing can be maintained.

  The thickness of the second flexible polyurethane foam sheet is preferably 1.0 to 8.0 mm, more preferably 3.0 to 5.0 mm. When the thickness is 1.0 mm or more, the unevenness due to embossing can be retained. When the thickness is 8.0 mm or less, the cushioning property and the durability of the uneven design can be maintained.

The density of the flexible polyurethane foam sheet (JIS K7222 apparent density) is preferably a second flexible polyurethane foam sheet is 18~60kg / m ^3, the first flexible polyurethane foam sheet is 18~60kg / m ³ Preferably. When the respective densities are equal to or more than the lower limit values, the cushioning property and the durability of the uneven design can be maintained. Further, when the respective densities are not more than the upper limit value, the cushioning property and the moldability can be maintained.

  The hardness (JIS K6400-2D method) of the flexible polyurethane foam sheet is preferably 36 to 360 N for the second flexible polyurethane foam sheet, and 72 to 360 N for the first flexible polyurethane foam sheet. .. When each hardness is equal to or higher than the lower limit value, cushioning properties and durability of the uneven design can be maintained. Further, when the hardness of each is less than or equal to the upper limit value, cushioning properties and moldability can be maintained.

  The rebound resilience (JIS K6400-3) of the flexible polyurethane foam sheet is preferably 20% or more for the second flexible polyurethane foam sheet and 20% or more for the first flexible polyurethane foam sheet. When each impact resilience is equal to or more than the lower limit value, the cushioning property can be maintained.

  The compression residual strain (JIS K6400-4 A method 50% compression) of the flexible polyurethane foam sheet is preferably 30% or less for the second flexible polyurethane foam sheet, and 10% or less for the first flexible polyurethane foam sheet. Is preferred. When the respective compressive residual strains are not more than the upper limit value, the cushioning property can be maintained. The compression residual strain of the second flexible polyurethane foam sheet is preferably 10% or more, and more preferably 15% or more in order to improve the shapeability of the embossed design by embossing.

  The compressive residual strain (JIS K6400-4 A method 50% compression) of the flexible polyurethane foam sheet laminate including the first flexible polyurethane foam sheet and the second flexible polyurethane foam sheet (ie, the laminated flexible polyurethane foam sheet) is It is preferably from 2 to 10%. When the residual compressive strain is equal to or more than the lower limit value, it is possible to improve the imprintability of the uneven design by embossing. Further, when the residual compression strain is not more than the upper limit value, cushioning properties can be maintained.

  Regarding the repeated compression residual strain (JIS K6400-4 B method, constant displacement method, 50% compression at room temperature of 80,000 times) of the flexible polyurethane foam sheet, the second flexible polyurethane foam sheet is preferably 5% or less, It is preferable that the flexible polyurethane foam sheet of 1 is 5% or less. When the respective cyclic compression residual strains are not more than the upper limit value, the cushioning property can be maintained.

  As described above, the flexible polyurethane foam sheet is formed by stacking at least one layer of the second flexible polyurethane foam sheet and at least one layer of the first flexible polyurethane foam sheet. Three layers in which the second flexible polyurethane foam sheet is sandwiched between the two first flexible polyurethane foam sheets, that is, as shown in FIG. 2, the first flexible polyurethane foam sheet 2 is replaced by the second flexible polyurethane foam sheet 3. It is preferable to stack and use not only the upper surface (that is, the front surface) but also the lower surface (that is, the back surface) from the viewpoint of the shapeability and cushioning property of the uneven design and the durability of the uneven design.

  The method for laminating and integrating the skin material and each flexible polyurethane foam sheet is not particularly limited, and examples thereof include a method using an adhesive and a method using a frame laminate. Among them, the method using frame lamination is preferable from the viewpoint of process load and weight reduction.

  On the surface of the soft polyurethane foam sheet opposite to the surface material side, further, it is possible to prevent stains on the embossing roll during embossing, to allow the composite material to slide smoothly during sewing work, and to prevent damage to the urethane foam. From the viewpoint of prevention, the back cloth may be laminated. Examples of the back cloth include cloth made of synthetic fiber such as polyester.

  The method for laminating and integrating the backing cloth may be the same as the method for integrating the skin material and the flexible polyurethane foam sheet. Among them, the method using frame lamination is preferable from the viewpoint of process load and weight reduction.

  Thus, the embossing composite material of this embodiment is obtained.

  The resulting composite material is embossed. That is, a heated embossing die (for example, an embossing roll or a flat plate-like embossing die) is pressed against the surface of the skin material of the composite material to form an uneven design. As a result, an embossed product that is an uneven design forming composite material is obtained. FIG. 3 is a diagram schematically showing a cross section of the obtained embossed product 10, in which a recess 11 is formed by embossing on the surface.

  The embossed design can typically include a texture pattern, but is not limited thereto. For example, it may be a fabric pattern such as a woven fabric or a denim fabric, or a geometric pattern in which random points, lines, circles, triangles, quadrangles, etc. are used alone or in combination of two or more.

  The surface temperature of an embossing die such as an embossing roll or a flat plate-like embossing die (that corresponds to the heat treatment temperature at the time of heating and pressing) may be appropriately set according to the material of the skin material or the flexible polyurethane foam sheet. For example, when the material of the skin material is polyethylene terephthalate (melting point: 260 ° C), the surface temperature is preferably 60 to 210 ° C, more preferably 80 to 180 ° C. When the temperature is 60 ° C. or higher, it is possible to maintain the durability of the formed uneven design, particularly the heat resistance. When the temperature is 210 ° C. or less, it is possible to suppress the gloss of the surface of the skin material from becoming strong and the texture of the embossed product from becoming coarse and hard.

  The time for pressing the heated embossing roll against the skin material varies depending on the shape of the uneven design, but the pressing time is preferably 0.01 to 5 seconds, more preferably 0.1 to 2 seconds. Further, in the case of an embossing device having a flat plate embossing die, the pressing time is preferably 30 to 120 seconds, more preferably 50 to 90 seconds. When the pressing time is equal to or longer than the lower limit value, a clear uneven design can be formed, and the durability of the uneven design can be maintained. When the pressing time is less than or equal to the upper limit value, it is possible to prevent the texture from becoming coarse and hard, discoloring, and productivity being deteriorated.

  The processing speed in the case of processing using an embossing device equipped with an embossing roll is usually 0.1 to 10 m / min, preferably 0.3 to 5 m / min. The processing speed in the case of processing using an embossing device equipped with a flat plate embossing die is usually 0.5 to 6 m / min, preferably 0.6 to 3 m / min.

  The pressure at the time of pressing is preferably 1 to 10 MPa, more preferably 2 to 5 MPa. When the pressure is 1 MPa or more, a clear uneven design can be formed. When the pressure is 10 MPa or less, it is possible to prevent the texture from becoming coarse and hard.

  Thus, the uneven design is formed on the surface of the skin material. As described above, the thickness of each layer changes before and after the embossing process, especially in the concave and convex design, particularly in the concave portion formed by pressing the embossed convex portion. The thickness T0 (see FIG. 3) of the composite material in the recess 11 after embossing is 1.5 to 5.0 mm, preferably 1.5 to 3.0 mm. When the thickness T0 is 1.5 mm or more, it is possible to suppress the gloss of the concave portion due to the surface being crushed by the heat of embossing, and to suppress the deterioration of the designability. When the thickness T0 is 5.0 mm or less, the concavo-convex design becomes clear, and the durability and kneading resistance of the concavo-convex design can be maintained.

  The thickness T1 (see FIG. 3) of the first flexible polyurethane foam sheet 2 in the recess 11 after embossing is preferably 1.0 to 3.0 mm, more preferably 1.0 to 2.0 mm. is there. When the thickness T1 is 1.0 mm or more, the cushioning property can be maintained. When the thickness T1 is 3.0 mm or less, the concavo-convex design can be made clear.

  The thickness T2 of the second flexible polyurethane foam sheet 3 in the recess 11 after embossing is preferably 0.1 to 0.5 mm, more preferably 0.2 to 0.3 mm. When the thickness T2 is 0.1 mm or more, it is possible to suppress a decrease in the volume feeling of the uneven design. When the thickness T2 is 0.5 mm or less, the uneven design can be made clear.

  The depth D (see FIG. 3) of the concave portion 11 is preferably 3.0 mm or more, so that the uneven design can be made clear. The upper limit of the depth D is not particularly limited, but may be 8.0 mm or less, for example.

  In the concave portion formed by embossing, the ratio of the thickness after embossing to the thickness before embossing, that is, the compression rate before and after embossing, is determined by the first flexible polyurethane foam sheet when imprinting an uneven design. 14 to 100% is preferable from the viewpoint of the cushioning property and the cushioning property, and 1.3 to 10% is preferable from the viewpoint of the moldability of the uneven design and the cushioning property in the second flexible polyurethane foam sheet.

  Further, it is preferable to preheat the composite material before the concavo-convex design is formed (before embossing) with near infrared rays, because the pressing time can be shortened and the processing efficiency is improved.

  Thus, the embossed product of this embodiment can be obtained.

  Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples. Further, the evaluation of the composite material having the concavo-convex design was performed according to the following method.

(1) Concavo-convex design moldability The concavo-convex design forming composite material subjected to embossing was evaluated according to the following evaluation criteria.
(Evaluation criteria)
A: The depth of the recess is 3.0 mm or more, and the uneven design is clearly formed.
B: When the depth of the recess is more than 2.0 mm and less than 3.0 mm, the uneven design is slightly unclear.
C: The concave / convex design is unclear when the depth of the concave portion is 2.0 mm or less.

(2) Cushioning property The uneven design forming composite material was evaluated according to the following evaluation criteria.
(Evaluation criteria)
A: It is almost equivalent to the cushioning property of the soft urethane foam before embossing.
B: The soft urethane foam before embossing is slightly inferior in cushioning property.
C: The soft urethane foam before embossing is inferior in cushioning property.

(3) Concavo-convex design durability The concavo-convex design forming composite material of each of the examples and comparative examples used in the durability test is one in which a clear concavo-convex design is formed and is adopted. An automobile seat was made using the material as a skin, and a durability tester (manufactured by TMETEC Co., Ltd.) was used to carry out a durability test 8000 times (23 ° C., 50% RH environment). The test piece after the durability test was observed and evaluated according to the following criteria.
(Evaluation criteria)
A: The uneven shape clearly remains.
B: There is a part where the uneven shape is slightly unclear.
C: The uneven shape is slightly unclear.
D: The uneven shape is unclear

[Example 1]
The first flexible polyurethane foam sheet 2 having a thickness of 3.0 mm is laminated on both sides of the second flexible polyurethane foam sheet 3 having a thickness of 5.0 mm, and the fabric A (warp: 180 dtex / 156 f PET is used as the skin material 1). Multifilament yarn, weft yarn: PET multifilament processed yarn of 167 dtex / 48f, mass 300 g / m ² , thickness 0.9 mm, satin weave), knitted fabric B (polyester half tricot knitted fabric, thickness 0.3 mm) as backing fabric 4 Were integrated by frame lamination to prepare a composite material having a layered structure as shown in FIG. Table 1 shows the physical property values of the flexible polyurethane foam sheet used. The thickness of each layer such as the flexible polyurethane foam sheet after frame lamination has the value shown in Table 2.

  In addition, the softening point uses a thermomechanical analyzer (EXSTAR TMA-SS6100 / DSC6200 manufactured by Hitachi High-Tech Science Co., Ltd.) as a tester, and an expansion measurement probe having a flat tip as an indenter (probe tip diameter: 3.5 mm). Was measured using. A force of 100 mN was applied to the indenter, which was gently placed in the center of the sample (circular with a diameter of 10 mm, thickness of 10 mm) and continuously displaced in the vertical direction of the applied indenter when heated at a heating rate of 10 ° C./min. The softening point was defined as the temperature at which abrupt displacement due to softening of the sample started.

  Then, using an embossing machine with an outer diameter of the embossing roll of 250 mm and an outer diameter of the backup roll of 350 mm, the embossing roll surface temperature is 180 ° C., the backup roll surface temperature is 230 ° C., the roll pressure is 2 MPa, and the embossing speed is 2 m / min. did. The embossing roll has a concavo-convex design in which straight lines having a width of 1 mm and a length of 20 mm to 50 mm are obliquely combined, and a groove depth of 12 mm is prepared. The surface of the composite skin material was placed on the embossing roll side for embossing. Table 2 shows the thickness of each layer of the recess after embossing, the depth of the recess, and the evaluation results.

[Example 2]
In the same manner as in Example 1 except that the flexible polyurethane foam sheet was changed as shown in Table 2, they were laminated and integrated by frame lamination, and a composite material having a layer structure as shown in FIG. 1 was prepared and then embossed. .. Table 2 shows the thickness of each layer of the recess after embossing, the depth of the recess, and the evaluation results.

[Comparative Examples 1 and 2]
In the same manner as in Example 1 except that the flexible polyurethane foam sheet was changed as shown in Table 2, the sheets were laminated and integrated by frame lamination and embossed. Table 2 shows the thickness of each layer of the recess after embossing, the depth of the recess, and the evaluation results.

  The products obtained in the examples had deep rugged designs, and were excellent in all of the ruggedness design moldability, cushioning property, and ruggedness design durability. On the other hand, the product obtained in Comparative Example 1 had shallow unevenness and was inferior in the evaluation of the irregularity design formability, and the product obtained in Comparative Example 2 was inferior in the evaluation of the cushioning property and the irregularity design durability. ..

  The embossed product according to the embodiment of the present invention can be used, for example, as an interior material for various vehicles such as automobiles and railway vehicles, and as a surface material for chairs such as vehicles and interiors.

  Although some embodiments have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention.

1 Skin Material 2 1st Flexible Polyurethane Foam Sheet 3 2nd Flexible Polyurethane Foam Sheet 4 Backing Material 5 Embossing Composite Material 10 Embossing Product 11 Recess

Claims (10)

  A composite material for embossing, in which a first flexible polyurethane foam sheet and a second flexible polyurethane foam sheet are sequentially laminated on the back surface of a skin material, wherein the softening point of the first flexible polyurethane foam sheet is Composite material for embossing, which has a higher softening point than that of the soft polyurethane foam sheet of 2.   The embossing composite material according to claim 1, wherein the first flexible polyurethane foam sheet is also laminated on the back surface of the second flexible polyurethane foam sheet.   The embossing composite material according to claim 1 or 2, wherein the skin material is at least one selected from the group consisting of woven fabric, knitted fabric, non-woven fabric, and leather.   The softening point of the said 1st flexible polyurethane foam sheet is 150 degreeC-200 degreeC, and the softening point of the said 2nd flexible polyurethane foam sheet is 90 degreeC-110 degreeC, Any one of Claims 1-3. The composite material for embossing according to.   5. The thickness of the first flexible polyurethane foam sheet is 2.0 to 7.0 mm, and the thickness of the second flexible polyurethane foam sheet is 1.0 to 8.0 mm. The composite material for embossing according to any one of items.   The compression residual strain of the said 1st flexible polyurethane foam sheet is 10% or less, and the compression residual strain of the said 2nd flexible polyurethane foam sheet is 10 to 30%, In any one of Claims 1-5. The composite material for embossing described.   The compression set of the flexible polyurethane foam sheet laminate including the first flexible polyurethane foam sheet and the second flexible polyurethane foam sheet is 2 to 10%, and the compression set according to any one of claims 1 to 6. Composite material for embossing.   An embossed product comprising the composite material for embossing according to any one of claims 1 to 7, wherein the surface of a skin material of the composite material for embossing is embossed.   In the recess formed by the embossing, the thickness of the first flexible polyurethane foam sheet is 1.0 to 3.0 mm and the thickness of the second flexible polyurethane foam sheet is 0.1 to 0.5 mm, The embossed product according to claim 8, wherein the recess has a depth of 3.0 mm or more.   In the recesses formed by the embossing, the ratio of the thickness after embossing to the thickness before embossing of the first flexible polyurethane foam sheet is 14 to 100%, and the second flexible polyurethane foam sheet. The embossed product according to claim 8 or 9, wherein the ratio of the thickness after embossing to the thickness before embossing is 1.3 to 10%.

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