JP2009203418A - Method for molding real-leather skin material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for molding a real-leather skin material which has a three-dimensional shape, with preventing the rugged pattern formed on the surface of the skin material from disappearing. <P>SOLUTION: The invention relates to a method for molding a real-leather skin material 1 whose skin material 2 has an emboss pattern formed on the surface. The method comprises: a coating process of coating a liquid-state acrylic resin 40 on the back surface of the skin material 2; a skin material-moisture removal process of removing a moisture content which is contained in the skin material 2, from the skin material 2 coated with the acrylic resin 40; a hot-pressing process of laying the skin material 2, which is coated with the acrylic resin 40, on a pressing machine 70 heated at a temperature not lower than a softening point of the acrylic resin 40 and of shaping the skin material 2 into a three-dimensional shape by the hot pressing; and after the hot pressing, a molding removal process of cooling the skin material 2 with keeping the shaped state by means of the pressing machine 70 and of removing the skin material 2 from the pressing machine 70. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for forming a leather skin material.

A seat cushion or the like of a vehicle seat has a configuration in which a cushion material is covered with a skin material, and the skin material has a three-dimensional shape. A genuine leather skin material using genuine leather as a material of the skin material is known as described in Patent Document 1 below. The genuine leather skin material described in Patent Document 1 is formed into a bag shape by sewing together pieces of leather cut into a predetermined shape and sewing them into a three-dimensional shape that matches the surface shape of the cushion material. This genuine leather skin material has a structure in which leather pieces are joined together by sewing.
JP 2006-204326 A

  However, in the said structure, a sewing line appears in an external appearance and the external appearance design of a genuine leather skin material is restrict | limited. Therefore, it is conceivable to form a genuine leather skin material into a three-dimensional shape by molding in order to avoid being restricted by the appearance design. However, since the leather contains moisture, the moisture evaporates during the hot press to generate water vapor, and the press machine acts as an iron to serve as a steam iron. An uneven pattern such as a texture pattern formed on the surface may become flat and disappear.

  The present invention has been completed based on the above circumstances, and formed a leather cover material having a three-dimensional shape by molding while preventing the disappearance of the uneven pattern formed on the surface of the cover material. The purpose is to do.

  The present invention relates to a method for forming a genuine leather skin material having a concavo-convex pattern formed on the surface of the skin material, wherein an application step of applying a liquid thermoplastic resin to the back surface of the skin material, and a thermoplastic resin is applied. The skin material moisture removal process for removing moisture contained in the skin material from the skin material, and the skin material coated with the thermoplastic resin are placed on a press machine heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin. , A hot press process for shaping the skin material into a three-dimensional shape by hot pressing, and after hot pressing, the skin material is cooled while maintaining the shaping state by the press machine, and the skin material is removed from the press machine. It is characterized in that it comprises a mold process.

  According to such a method for forming a leather skin material, since the skin material moisture removing step is provided, moisture contained in the skin material can be removed, and the generation of water vapor during hot pressing can be prevented. it can. Therefore, even if the skin material is shaped into a three-dimensional shape by a press machine, there is no water vapor, so the press machine does not function as a steam iron and can be molded while maintaining the uneven pattern of the skin material. . In addition, by making it possible to form a genuine leather skin material having a three-dimensional shape by molding, cutting and sewing processes can be reduced.

As an embodiment of the present invention, the following is preferable.
In the skin material moisture removing step, moisture may be removed by heating the skin material coated with the thermoplastic resin.
When moisture is removed by heating the skin material in this manner, the skin material shrinks due to heating, so that even when the skin material is subsequently stretched by hot pressing, the amount of elongation from the initial state can be kept low.

The thermoplastic resin may be an acrylic resin.
Thus, when an acrylic resin is used as the thermoplastic resin, it can be easily molded without impairing the characteristics (flexibility, etc.) of the genuine leather.

  ADVANTAGE OF THE INVENTION According to this invention, the genuine leather skin material which has a three-dimensional shape can be formed by shaping | molding, preventing disappearance of the uneven | corrugated pattern currently formed in the surface of the skin material.

<Embodiment>
An embodiment of the present invention will be described with reference to the drawings of FIGS. The genuine leather skin material 1 in the present embodiment is a seat skin material used for a seat cushion or a seat back of a vehicle seat (not shown). This skin material for a sheet is configured to include and cover a cushion material or the like, and is formed into a large arc shape or bag shape (an example of the “three-dimensional shape” of the present invention). FIG. 1 shows a cross-sectional structure of a genuine leather skin material 1. 1 is the front side of the leather skin material 1, and the upper side is the back side of the leather skin material 1.

  The genuine leather skin material 1 includes a coating layer 10, a silver surface layer 20, and a fiber layer 30 in that order from the surface side. On the surface of the leather skin material 1, a texture pattern (an example of the “concave / convex pattern” of the present invention) unique to genuine leather is formed. The silver surface layer 20 constitutes a surface layer of genuine leather, and the leather is composed of the silver surface layer 20 and the fiber layer 30. Genuine leather is finer as it goes from the back side to the front side of the leather skin material 1, and moisture is contained inside the genuine leather. The coating layer 10 is a protective film coated for the purpose of protecting the silver surface layer 20 of genuine leather.

  The fiber layer 30 is configured by interlacing a plurality of fibers, and a gap is formed between these fibers. On the back surface of the fiber layer 30 (the surface opposite to the silver surface layer 20), the acrylic resin 40 is impregnated in the gaps of the fibers and cured. Thereby, the genuine leather skin material 1 has flexibility and is held in a certain form.

  Next, a method for manufacturing the genuine leather skin material 1 in the present embodiment will be described with reference to the drawings of FIGS. In the following description, the genuine leather skin material 1 before completion is referred to as a skin material 2. A skin material 2 that is a base material of the genuine leather skin material 1 includes a coating layer 10, a silver surface layer 20, and a fiber layer 30 that is not impregnated with an acrylic resin 40.

First, as a method of applying a liquid thermoplastic resin, in this embodiment, a roll coater type coating machine 60 is used, and a genuine leather whose gravure (intaglio) type is rotated in the same direction as the feed direction of the leather skin material 1. Acrylic resin 40, which is a thermoplastic resin, is supplied to the application roll 61 on the back surface (fiber layer 30) side of the skin material 1, and the genuine leather skin material 1 is sandwiched between the application roll 61 and the feed roll 62 facing the application roll 61. The acrylic resin 40 is applied to the back surface of the leather cover material 1 while being fed. The acrylic resin 40 can be impregnated into the fiber layer 30 by the pressing force of the application roll 61 by making the gap between the application roll 61 and the feed roll 62 narrower than the thickness of the leather cover material 1 (application process). In addition, the application amount of the acrylic resin 40 applied to the fiber layer 30 is set to be 1 g / dm ² .

  As shown in FIG. 3, the skin material 2 to which the acrylic resin 40 is applied in the application process is heated from the back side by a drying device 50 such as an infrared heater. The drying device 50 includes a base 51 and an infrared radiation unit 52 that radiates and heats infrared rays 53 from above to the skin material 2 placed on the base 51. The surface side of the skin material 2 is placed on the base 51, and the back surface side of the skin material 2 is disposed opposite to the infrared radiation portion 52. The infrared radiation part 52 is set so that the temperature of the skin material 2 placed on the base 51 becomes a temperature at which moisture can be evaporated (100 ° C. to 120 ° C.). Thereby, as for the skin material 2, the water | moisture content contained in the inside of the fiber layer 30 is removed when the back surface side of the fiber layer 30 is heated preferentially. The moisture content of the skin material 2 is preferably 10% or less, more preferably 5% or less (skin material moisture removal step).

  Moreover, the skin material 2 contracts from the initial state before heating by the heating by the drying device 50. However, as will be described later, the skin material 2 may be stretched by hot pressing. In this case, the amount of elongation from the initial state can be reduced. In addition, although the acrylic resin 40 is apply | coated to the back surface of the fiber layer 30, the gap | interval of a fiber is not completely obstruct | occluded and it is possible to dry it. If the acrylic resin 40 is applied after the skin material 2 is dried, the skin material 2 absorbs moisture at the time of application. Therefore, it is preferable to dry the skin material 2 to which the acrylic resin 40 is applied.

  As a method of drying the skin material 2, in addition to the method of applying the infrared ray 53 to the skin material 2 and drying, the method of applying warm air to the skin material 2 and drying the skin material 2 at normal temperature Alternatively, a method of drying and a method of vacuum drying the skin material 2 may be employed. Alternatively, the skin material 2 may be placed and dried in a drying chamber in which a desiccant such as calcium chloride or silica gel is installed, or the skin material 2 is placed on a belt conveyor and conveyed through a heating furnace. It may be dried.

  Thus, the skin material moisture removing step is intended to remove moisture contained in the fiber layer 30, and if the purpose is simply to remove moisture, the hot pressing step described below is performed by hot pressing. It may be necessary to heat the skin material 2, and it seems that there is no need to provide a skin material moisture removing step. However, when the skin material 2 is heated by hot pressing, the texture pattern formed on the surface of the skin material 2 due to the steam iron effect disappears. For this reason, in this embodiment, the skin material moisture removal process is intentionally provided separately from the hot press process.

  The skin material 2 from which moisture has been removed in the skin material moisture removal step is set in the press machine 70. The press machine 70 includes a pair of upper and lower forming dies 71 and 72 that can approach and separate in the vertical direction. The upper mold 71 of the press machine 70 includes a main body 73 and a slide core 74 that can move relative to the main body 73. On the other hand, the lower mold 72 has a recess 75, and a plurality of suction holes 76 are opened on the bottom surface of the recess 75. The suction hole 76 communicates with a vacuum pump 77 and can be evacuated by driving the vacuum pump 77.

  The upper and lower molds 71 and 72 of the press machine 70 are heated to a temperature equal to or higher than the softening temperature of the acrylic resin 40 (80 ° C. to 120 ° C.). It is placed on the outer peripheral portion 75A of the recess 75 in the lower mold 72 toward the mold 72 side. Next, by moving only the main body 73 of the upper die 71 toward the lower die 72, the skin material 2 is sandwiched between the main body 73 and the outer peripheral portion 75A of the recess 75 as shown in FIG. At this time, the interval between the main body 73 and the outer peripheral portion 75 </ b> A of the recess 75 is set to be slightly larger than the plate thickness of the skin material 2. Therefore, the skin material 2 is movable between the main body portion 73 and the outer peripheral portion 75A of the recess 75.

  After that, when the vacuum pump 77 is operated to evacuate the recess 75 through the suction hole 76 and the skin material 2 is drawn into the bottom surface of the recess 75, the skin material 2 is pulled by the suction hole 76 as shown in FIG. It will be in the state attracted | sucked by the bottom face of the recessed part 75. FIG. In this state, the skin material 2 is shaped in a form along the inner surface of the recess 75. And when the slide core part 74 of the upper mold | type 71 is moved toward the lower mold | type 72, keeping the shaping state by the suction hole 76, as shown in FIG. A three-dimensional shape is formed by being sandwiched between the outer surface of the slide core portion 74 and hot pressing (hot pressing step).

  After the heat pressing, the skin material 2 is cooled while the shaping state by the press machine 70 is maintained. Since the genuine leather has a property of maintaining a shaping state for a while after the hot pressing, the skin material 2 does not return to its original shape even if the acrylic resin 40 is softened. For this reason, when both the upper and lower molds 71 and 72 are opened, the acrylic resin 40 is solidified and the skin material 2 is held in a three-dimensional shape. Thereafter, by removing the skin material 2 from the press machine 70, a genuine leather skin material 1 having a three-dimensional shape is obtained as shown in FIG. 8 (demolding step).

  As described above, in the present embodiment, the skin material moisture removing step is provided before the hot pressing step, and the skin material 2 is hot-pressed in a dried state, so that generation of water vapor during hot pressing is prevented. Can do. Therefore, it can prevent that the press machine 70 plays the role of a steam iron and a wrinkle pattern disappears. As a result, the genuine leather skin material 1 can be formed into a three-dimensional shape, and the cutting and sewing steps that have been conventionally required can be eliminated.

  In addition, when the skin material 2 is contracted by heating due to the removal of moisture by heating the skin material 2, when the skin material 2 is subsequently stretched by hot pressing, the amount of elongation from the initial state is kept low. Can do. Furthermore, since the acrylic resin 40 is used as the thermoplastic resin, it can be easily molded without impairing the properties (flexibility, etc.) of the genuine leather.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) Although the acrylic resin 40 is used as the thermoplastic resin in the present embodiment, according to the present invention, the thermoplastic resin is not limited to the acrylic resin 40, and other thermoplastic resins may be used.

  (2) Although the acrylic resin 40 is applied to the fiber layer 30 using the roll coater type coating machine 60 in this embodiment, according to the present invention, the fiber layer 30 using the spray nozzle 63 as shown in FIG. Alternatively, the acrylic resin 40 may be sprayed on the surface.

  (3) Although the embossed pattern is illustrated as an uneven pattern in the present embodiment, according to the present invention, it may be a satin texture, a wood grain, a texture, or the like.

A figure showing the cross-sectional structure of a genuine leather skin material The figure which showed a mode that the acrylic resin was apply | coated to a skin material using the coating machine of a roll coater system in an application | coating process. The figure which showed the skin material moisture removal process which dries the skin material The figure which showed the state which placed the skin material on the lower mold in the hot press process The figure which showed the state which moved the main-body part of the upper model to the lower model The figure which showed the state which evacuated the skin material with the adsorption hole The figure which showed the state which moved the slide core part of the upper model to the lower model Figure showing the demolding process of opening the upper and lower molds and demolding the leather skin material The figure which showed a mode that an acrylic resin was sprayed and applied to a skin material using an injection nozzle in an application process

Explanation of symbols

1 ... Genuine leather skin material 2 ... Skin material 40 ... Acrylic resin (thermoplastic resin)
50 ... Drying device 70 ... Press machine

Claims (3)

A method for forming a leather skin material in which an uneven pattern is formed on the surface of the skin material,
An application step of applying a liquid thermoplastic resin to the back surface of the skin material;
A skin material moisture removing step for removing moisture contained in the skin material from the skin material coated with the thermoplastic resin;
A hot pressing step of placing the skin material coated with the thermoplastic resin on a press machine heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin, and shaping the skin material into a three-dimensional shape by hot pressing. When,
After the heat pressing, the leather material is characterized by comprising a demolding step of cooling the skin material while maintaining the shaping state by the press machine and demolding the skin material from the press machine Molding method. The method for molding a genuine leather skin material according to claim 1, wherein in the skin material moisture removing step, the moisture is removed by heating the skin material to which the thermoplastic resin is applied. The method for molding a leather skin material according to claim 1 or 2, wherein the thermoplastic resin is made of an acrylic resin.

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