JPH0653133U - Molding sheet - Google Patents

Abstract

(57) [Abstract] [Purpose] To facilitate the production and enhance the moldability of a molding sheet having a foam layer and a skin material layer. [Structure] The molding sheet 1 includes a polyolefin resin foam layer 2 and a polyurethane resin skin layer 3 disposed on one side of the polyolefin resin foam layer 2.
The polyurethane resin skin layer 3 is formed, for example, by directly coating a polyurethane resin on the polyolefin resin foam layer 2.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a molding sheet, particularly a molding sheet including a resin foam layer and a skin layer.

[0002]

[Prior art]

 As a forming sheet for producing daily necessities such as bags and bags and interior materials for vehicles, a composite sheet in which synthetic leather is laminated on a polyolefin resin foam is known (Shokai Sho 62-139620). . This composite sheet can be formed into a desired shape such as a vehicle interior material or a bag by a thermoforming method such as vacuum forming.

[0003]

[Problems to be solved by the device]

 The conventional molding sheet is manufactured by bonding synthetic leather to a polyolefin resin foam. However, because synthetic leather is a woven fabric such as woven fabric or knitted fabric coated with polyurethane resin (for example, “Actual knowledge of leather (1.2.3. Synthetic leather” issued on November 22, 1975). ) ”: Toyo Keizai Co., Ltd.) In the process for producing the molding sheet, a process for producing synthetic leather and a process for laminating synthetic leather on a polyolefin resin foam are required. Therefore, it requires a lot of man-hours and is not easy to manufacture.

Further, the conventional forming sheet is difficult to be formed into a complicated shape by deep drawing or the like, because the formability is affected by the elongation of the woven fabric forming the synthetic resin layer. Even if the elongation of the woven fabric is increased to improve the formability, the weave and stitches of the woven fabric are likely to appear as irregularities on the surface of the polyurethane resin coat layer, and a molded product with a good appearance can be obtained. Absent. In addition, it is difficult to obtain a sharp cut product because the woven cloth is present when it is processed into a product. Furthermore, when the product is subjected to embossing to give marks, patterns, etc., the texture of the woven cloth appears on the surface as the depth increases, and a molded product with a good appearance cannot be obtained. Furthermore, the conventional forming sheet lacks a sense of unity because the base cloth has a great influence on the texture.

An object of the present invention is to facilitate the production of a molding sheet having a foam layer and a skin material layer, and enhance the processability and texture of the product such as moldability, embossing workability and cutting property. There is something to do.

[0006]

[Means for Solving the Problems]

 The molding sheet of the present invention comprises a polyolefin resin foam layer and a polyurethane resin skin layer arranged on one side of the polyolefin resin foam layer. Here, the polyurethane resin skin layer includes, for example, a base layer made of a porous polyurethane resin and a surface layer made of a non-porous polyurethane resin.

A backing layer, for example, is further laminated on the other surface of the polyolefin resin foam layer. *** Structure of Molding Sheet FIG. 1 is a longitudinal sectional view of a molding sheet 1 according to an example of the present invention. The molding sheet 1 is mainly composed of a polyolefin resin foam layer 2 and a polyurethane resin skin layer 3 disposed on the upper surface of the polyolefin resin foam layer 2 in the figure.

In this molding sheet 1, the polyurethane resin skin layer 3 is usually composed of a single polyurethane resin layer. However, as shown in FIG. 2, the polyurethane resin skin layer 3 has a multi-layered structure including a base layer 3a made of a porous polyurethane resin and a surface layer 3b made of a non-multiporous polyurethane resin. Good. When the polyurethane-based resin skin layer 3 has a multi-layered structure in this manner, in the molding sheet 1 of FIG. 1, a flaw (for example, a scratch) generated on the polyurethane-based resin skin layer 3 is immediately corrected. The scratches reaching the layer 2 tend to cause peeling between the polyurethane-based resin skin layer 3 and the polyolefin-based resin foam layer 2, whereas the scratches generated on the surface layer 3b are caused by the base layer 3a. It becomes difficult to reach the layer 2, and the polyurethane-based resin skin layer 3 and the polyolefin-based resin foam layer 2 are less likely to peel off.

As shown in FIG. 3, a backing layer 4 may be further laminated on the other surface of the molding sheet 1. In this case, since both surfaces of the polyolefin resin foam layer 2 are covered with the skin layer 3 and the backing layer 4, respectively, it is necessary to cover both the front side and the inner side such as a bag. Goods can be manufactured easily. The backing layer 4 can also serve as a reinforcing material for the molding sheet 1. Polyolefin resin foam layer The polyolefin resin foam layer used in the present invention is a general polyolefin such as polyethylene resin, polypropylene resin, mixed resin of polyethylene resin and polypropylene resin, vinyl acetate resin, etc. It is a foam layer made of a resin.

As the polyethylene resin, for example, a polyethylene resin having a density of 0.900 to 0.965 g / cc produced by a low pressure method, a medium pressure method, or a high pressure method, and an α-olefin such as butene or pentene are copolymerized. Examples thereof include linear polyethylene resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic ester copolymer resin and the like. These polyethylene resins may be used alone or in combination of two or more.

Examples of the polypropylene-based resin include homopolymers of propylene, block copolymer resins of α-olefins such as ethylene and butene and propylene, random copolymer resins and random-block copolymer resins. You can These polypropylene resins may be used alone or in combination of two or more.

The polyolefin-based resin may be mixed with a resin other than the polyolefin-based resin, such as petroleum resin or polystyrene resin. In addition, stabilizers, thickeners, lubricants, colorants, flame retardants, inorganic fillers such as titanium oxide and talc may be added. The polyolefin resin foam may be either a crosslinked polyolefin resin foam or a non-crosslinked polyolefin resin foam. However, when the crosslinked polyolefin resin foam is used, a molding sheet having better thermoforming processability can be obtained as compared with the case where the non-crosslinked polyolefin resin foam is used. As a cross-linking method of the polyolefin resin, a known method such as a chemical cross-linking method or an electron beam cross-linking method can be adopted, but the chemical cross-linking method is preferable in order to obtain better thermoformability.

The expansion ratio of the polyolefin-based resin foam layer is preferably 2 to 40 times, particularly preferably 5 to 20 times. Further, the thickness is preferably 2 to 15 mm, particularly preferably 4 to 10 mm. When the foaming ratio and the thickness are out of the above ranges, it is difficult to obtain a molded article having a good shape retention property, and the effect of the foam layer such as touch and cushioning property cannot be sufficiently obtained. When the polyolefin resin foam layer is made of a crosslinked polyolefin resin foam, the gel fraction is preferably 15 to 70, and particularly preferably 30 to 50. When the gel fraction is less than 15%, the pressure resistance of the foam layer is lowered. On the other hand, if it exceeds 70%, the elongation of the foam layer is lowered and the formability is lowered. The gel fraction is a value represented by weight% of insoluble matter remaining after 0.1 g of the foam sample was immersed in tetralin at 130 ° C. for 3 hours.

Further, the polyolefin-based resin foam layer is obtained by measuring the surface of the surface on which the polyurethane-based resin skin layer is laminated by the stylus method (point of tip 0.5 μmφ) in a surface roughness meter. Surface roughness is peak / valley-0.15 mm or less, 0.01 mm or more, preferably 0. It is set to be not more than 07 mm and not less than 0.01 mm. When the surface roughness is out of the above range, good adhesive strength between the polyolefin resin foam layer and the polyurethane resin skin layer cannot be obtained, and peeling between the two easily occurs. The above-mentioned surface roughness can be achieved by heating the surface of the resin foam to near the melting point and pressing the surface with a pressure roll. Polyurethane-based resin skin layer The polyurethane-based resin skin layer is disposed directly on one side of the polyolefin-based resin foam layer and is integrated with the polyolefin-based resin foam layer. Polyurethane-based resin The polyurethane-based resin constituting the skin layer is a general polyurethane-based resin obtained by reacting a polyol such as polyether polyol or polyethylene polyol with an isocyanate. Polyurethane resins used for synthetic leather are particularly preferable. Examples of polyurethane-based resins for synthetic leather include polyurethane-based resins and polyurethane-based resins containing various copolymerization components such as amino acids, amides and acrylics. If necessary, a polyamino acid resin, a polyamide resin, an acrylic resin, or a copolymer resin such as polyolefin or styrene may be added to such a polyurethane resin. It may also be colored.

The thickness of the polyurethane resin skin layer is not particularly limited, but is usually set to 0.01 to 2 mm. In particular, 0.05 to 0.2 mm is preferable. In addition, when the thickness is small, unevenness is likely to occur on the surface of the resin foam and insufficient strength is likely to occur. On the other hand, if the thickness is too large, problems in the manufacturing process are likely to occur. Further, the elongation percentage of the polyurethane resin skin layer is preferably 100% or more in both the longitudinal and transverse directions. If the elongation is less than 100%, the moldability of the molding sheet will be reduced. That is, it becomes difficult to deep-draw a forming sheet into a complicated shape. The elongation percentage here is a value measured by JIS No. 2 tumble.

The polyurethane-based resin skin layer may be composed of a single layer of the above-mentioned polyurethane-based resin, but as described above, a base layer made of a porous polyurethane-based resin and a surface layer made of a non-porous polyurethane-based resin A laminate of and is preferred. In this case, the above-mentioned polyurethane resin can be used for both the porous polyurethane resin forming the base layer and the non-porous polyurethane resin forming the surface layer. However, the polyurethane resin for the base layer may be mixed with other resins such as an olefinic thermoplastic elastomer and a polyamino acid resin, if necessary. Further, in the case of a polyurethane resin skin layer including such a base layer and a surface layer, the total thickness of the skin layer is 0. It is preferably set to 01 to 3 mm, particularly 0.2 to 0.6 mm. Of these, the thickness of the base layer needs to be set to 0.01 to 2 mm, preferably 0.2 to 0.5 mm. When the thickness of the base layer is less than 0.01 mm, it is difficult to obtain the effect of preventing separation between the polyurethane resin skin layer and the polyolefin resin foam layer as described above. On the contrary, when it exceeds 2 mm, the moldability of the molding sheet is deteriorated. Backing Layer The backing layer disposed on the other surface of the polyolefin resin foam layer is a cloth such as knitting, woven fabric, non-woven fabric, thermoplastic resin sheet or film such as polyolefin resin and vinyl chloride resin, or the above-mentioned. It is a resin layer similar to the polyurethane resin skin layer of. When the backing layer is a cloth, the material thereof may be natural fiber, chemical fiber, or a mixed fiber thereof. Examples of the natural fiber include wool, cotton and hemp. Examples of the chemical fiber include nylon fiber, polyester fiber, vinylon fiber, acrylonitrile fiber and the like. The mixed fiber may be a mixture of natural fibers such as a mixture of wool and cotton, a mixture of chemical fibers such as a mixture of nylon and polyester, or a mixture of natural fibers and synthetic fibers. .

Particularly preferred as backing layer is a woven fabric such as a woven or knitted fabric. This is because the woven cloth generally has a high elongation rate, so that it is possible to impart good moldability to the molding sheet. Knitting is particularly preferable. Further, a single chemical fiber is preferable as the fiber constituting the woven cloth. This is because the thermoforming processability of chemical fibers is better than that of natural fibers, and in the case of blended spinning, the setting of thermoforming conditions for forming sheets becomes complicated.

The elongation of the backing layer is preferably 50% or more, and particularly preferably 100% or more for the same reason as in the case of the polyurethane resin skin layer. The thickness can be appropriately set depending on the purpose of use of the molding sheet and the like, but is usually set to about 150 to 250 μm. The tensile strength of the backing layer is preferably larger than the tensile strength of the polyurethane resin skin layer. This is generally done in the forming process of the forming sheet so that the polyurethane resin skin layer side is on the outside, but at this time, if the strength of the woven fabric on the inside is large, the flat part of the formed product will be slightly outward. This is because the product will swell and a molded product with high appearance and quality can be obtained. Method of Manufacturing Molding Sheet The molding sheet of the present invention can be manufactured by the following two methods, for example. However, these methods are merely examples and do not limit the present invention. Manufacturing Method First, a polyolefin resin foam is prepared. Then, the polyurethane resin is applied to one surface of the polyolefin resin foam with a predetermined thickness to form a polyurethane resin skin layer. As a coating method, a known method using a brush, a spray, a coater, a roller or the like can be adopted.

When the polyurethane resin skin layer is composed of a base layer and a surface layer, first, on the polyolefin resin foam, a reactive urethane containing a compound capable of generating a reaction gas by heating or a thermal decomposition type foaming agent. A base resin layer is formed by uniformly applying a resin solution and heating it to generate a chemical reaction gas or generate physical bubbles. As the chemical reaction gas, a gas generated when the polyurethane is polymerized from the polyol and the isocyanate may be used. As the thermal decomposition type foaming agent, for example, azodicarbonamide, p-toluenesulfonyl hydrazide, 2'-azobis-2,4-dimethylvaleronitrile, 4,4'-oxybisbenzenesulfonyl hydrazide and the like are used. For the purpose of lowering the decomposition temperature, it is preferable to mix substances such as zinc oxide and metal soap with these foaming agents as decomposition accelerators. Next, a urethane resin solution is applied on the formed base layer to form a surface layer by a known method. The expansion ratio of the base layer is preferably set to 1.1 to 10 times, but this expansion ratio can be appropriately adjusted by the mixing amount of the foaming agent and the like.

The backing layer disposed on the other surface of the polyolefin resin foam layer is bonded by using a reactive adhesive such as polyester resin or polyurethane resin in the case of a fabric or a thermoplastic resin sheet. . The adhesion of the skin layer may be performed before or after the formation of the polyurethane resin skin layer. Manufacturing methodFirst, prepare a base sheet such as a release paper or a film coated with a release agent, and apply the urethane resin solution on the base sheet to a predetermined thickness using a well-known coating device such as a knife coater or roll coater. Apply. Then, the urethane resin solution is dried to form a polyurethane resin skin layer.

Next, a reactive adhesive such as a polyester resin or a polyurethane resin is applied to one surface of the polyolefin resin foam, and a polyurethane resin skin layer formed on the base sheet is bonded to the polyolefin resin foam to form a polyolefin resin. The resin foam and the polyurethane resin skin layer are bonded together. Then, when the base sheet is peeled off, a molding sheet is obtained.

In this manufacturing method, when the polyurethane-based resin skin layer has a laminated structure of a base layer and a surface layer, a multi-layered polyurethane-based resin base layer is laminated on the polyurethane-based resin skin layer formed on the base sheet. Form. The method of forming the base layer of the porous polyurethane resin is the same as that of the above-mentioned manufacturing method. The backing layer arranged on the other surface of the polyolefin resin foam is adhered in the same manner as in the manufacturing method. Use of Forming Sheet The forming sheet of the present invention can be formed into a shape such as an interior material for vehicles, daily necessities such as bags and bags by a heat forming method such as a vacuum forming method. Further, it can be formed into the above-mentioned use by sewing or the like.

[0023]

EXAMPLES Example 1 A release paper was coated with a urethane solution at a rate of 80 g / cm ² using a knife coater and dried to form a top layer. Then, a reactive urethane-based solution was applied onto the top layer at a rate of 150 / m ² by a roll coater method and heated. The reaction gas generated at that time formed a porous urethane layer. The expansion ratio of this porous urethane layer was 2.0.

On the other hand, a polyethylene foam having an apparent density of 0.10 g / cc and a gel fraction of 43% was prepared, and a 2-liquid type polyurethane adhesive was uniformly applied to the surface thereof at a rate of 50 g / m ^2. Applied. Then, the porous urethane layer formed on the release paper was bonded onto this adhesive, and the release paper was peeled off. Thereby, a molding sheet was obtained. Next, the obtained forming sheet was heated by an infrared heater so that the surface temperature was 150 ° C., and vacuum forming was performed using a cylindrical cup type (male type) to measure drawability. The cup mold used for molding has a diameter of 50 mm, the height (depth) of which can be changed, and the molding drawing ratio (depth / diameter) can be measured. According to this, the molding sheet of this example could be molded up to the region of the molding drawing ratio (0.60) of only the foam, and no cracking phenomenon of the skin material at the bottom was observed.

Further, the forming sheet was subjected to practical forming evaluation by a vacuum forming method using a male forming die for forming a bag (height 190 mm, width 330 mm, depth 50 mm and corner 10R). As a result, according to the molding sheet of the present example, the phenomenon of separation between the skin material and the foam at the corner (R) portion did not occur, and a practical molded product was obtained. Example 2 Instead of the polyethylene resin foam used in Example 1, a polypropylene resin foam having an apparent density of 0.067 g / cc, a gel fraction of 43% and a thickness of 5.1 mm was used. A composite sheet similar to Example 1 was produced. On the other main surface of the obtained composite sheet, a non-woven fabric containing polypropylene as a main component having an elongation of 150% and a basis weight of 100 g / m ² was attached using a polyester adhesive, and molded. Got a sheet for.

The obtained molding sheet was heated with an infrared heater until the surface temperature reached 140 to 150 ° C., and practical molding evaluation was performed by the same method as in Example 1. As a result, a practical molded product was obtained in which the skin material was not cracked at the R portion, the non-woven fabric was separated from the foam, and the foam material was not destroyed. Example 3, Comparative Examples 1 and 2, apparent density of 0.11 g / cc, gel fraction of 42%, thickness of 5 mm on one main surface of a polyethylene resin foam having an elongation of 140% and a basis weight of A 70 g / m ² knitted fabric was attached using a polyurethane adhesive to obtain a composite sheet. The same skin material as in Example 1 was pressure-bonded to the other main surface of this composite sheet using a polyester adhesive to produce a molding sheet. Table 1 shows the evaluation results of the obtained molding sheet.

[0027]

[Table 1]

The evaluation method is as follows. (Appearance) Surface irregularities, marks, changes in color and luster were observed. (Moldability) It was measured using the same cup mold as in Example 1.

In Comparative Example 1, when the drawing ratio was 0.3 or more, the base cloth and the foam separated. (Transition of Plasticizer) A sample was placed in a glass tube which was closed at one end and stood upright, and the other end of the glass tube was closed by a glass plate. Then, the sample was heated to 100 ° C. and the degree of cloudiness of the glass plate was observed. (Surface Abrasion Property) It was evaluated according to JIS K-7204 (Taber method). (Weight) A 10 × 10 cm ² sample was measured according to JIS-K-6328 and converted into g / m ² . (Handle) It was measured by the 45 ° cantilever method and the heart loop method according to JIS-L-1096. (Workability) The difficulty in the manufacturing process was evaluated. (Cutability) Punching was performed by a punching press and the cut surface was observed.

In the synthetic leather used in Comparative Example 1, since the base cloth is coated with urethane and polymerized, the base cloth easily expands and contracts, and the thickness accuracy is difficult to stabilize. (Evaluation Criteria) The criteria of ◯, Δ, and × shown in Table 1 are as follows. ◯: Good Δ: A little inferior to the case of ◯.

X: Use is possible, but there are problems, and there is a strong demand for improvement.

[0032]

[Effect of device]

 In the molding sheet according to the present invention, since the polyurethane resin skin layer is directly disposed on the polyolefin resin foam layer, the manufacturing is easy and the moldability is good. In the second invention, since the polyurethane resin skin layer is composed of the base layer and the skin layer as described above, in addition to the above effects, the polyurethane resin skin layer and the polyolefin resin foam layer are less likely to be peeled off. Further, the texture and feel are improved.

In the third invention, since both surfaces of the polyolefin resin foam layer are coated, in addition to the above-mentioned effects, a molded product which needs to be coated on both the front side and the back side with a skin material can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view of an example of the present invention.

FIG. 2 is a partial vertical sectional view of still another example of the present invention.

FIG. 3 is a partial vertical sectional view of an example of a third device.

[Explanation of symbols]

 1 Molding Sheet 2 Polyolefin Resin Foam Layer 3 Polyurethane Resin Skin Layer 3a Base Layer 3b Surface Layer 4 Backing Layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fukuyoshi Akimaru Inventor, 1-1 1-1 Sonoyama, Otsu-shi, Shiga Toga Ltd. Shiga Plant (72) Inventor Kimio Kimura 3-3 Nakanoshima, Kita-ku, Osaka No. 3 Toray Co., Ltd. (72) Inventor Nobuo Kitaguchi 4 123-2 Tanaka, Higashi-Osaka City, Osaka Prefecture Maron Co., Ltd. (72) Kenji Kurokawa 2 123-Tanaka, Nagano City, Higashi Osaka, Osaka Prefecture (72) Within the corporation

Claims (3)

[Scope of utility model registration request] 1. A molding sheet comprising: a polyolefin-based resin foam layer; and a polyurethane-based resin skin layer disposed on one surface of the polyolefin-based resin foam layer. 2. The molding sheet according to claim 1, wherein the polyurethane resin skin layer includes a base layer made of a porous polyurethane resin and a surface layer made of a non-porous polyurethane resin. 3. The molding sheet according to claim 1, further comprising a backing layer laminated on the other surface of the polyolefin resin foam layer.