JP5554559B2 - Method for producing foamed article with skin and foamed article with skin - Google Patents

Description

  The present invention relates to a method for producing a foam-molded article with a skin and a foam-molded article with a skin, and more particularly, to a method for producing a foam-molded article with a skin having excellent strength while being lightweight, and a foam-molded article with a skin.

The foamed molded body with a skin is lightweight, so that the skin side is used as a table, and is used for automobile interior parts such as cargo floor panels and rear parcel shelves, and interior parts for buildings such as inner wall partitions and doors.
As a method for producing such a foam-molded article with a skin, a method is known in which a cylindrical parison or a resin sheet is heated and melted and placed together with a skin material between divided molds and clamped (see, for example, Patent Document 1). ).

International Publication No. 06/043703 Pamphlet

  However, in the method for producing a foamed article with a skin described in Patent Document 1, when the parison is sandwiched between molds without completely adhering the wall surfaces of the parison, a hollow portion (hereinafter referred to as “hollow portion”) between the parisons. It is easy to generate. If it does so, as shown in FIG. 10, the foamed molded object 50 with a skin will become a structure in which the hollow part 51 remained in part, and intensity | strength, such as impact resistance, will become inadequate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for producing a foam-molded article with skin and a foam-molded article with skin, which are lightweight and have excellent strength.

  The present inventors have intensively studied to solve the above problems, and found that the above problems can be solved by deliberately going through a mold clamping step for securely adhering the inner wall surfaces facing each other of the foam parison. It came to complete.

That is, the present invention is a method for producing a foamed molded product with a skin comprising (1) a foamed molded product and a fiber skin material adhered to one surface of the foamed molded product, comprising a foaming agent and a thermoplastic resin. Extruding the mixed resin containing to make a foamed parison, and sandwiching the foamed parison and the fiber skin material with a split mold and sealing, thereby bringing the foamed parison and the fiber skin material into close contact with each other, and the foamed parison A mold clamping step for completely adhering the inner wall surfaces facing each other, and a suction step for increasing the volume of the foamed parison by sucking and depressurizing air in the divided mold after the mold clamping step is performed. It exists in the manufacturing method of a foam molding with a skin.

  In the present invention, (2) the split mold is composed of a first mold and a second mold, and a fiber skin material is suspended on the surface of the first mold on the side where the foam parison is sandwiched. In the method for producing a foamed article with a skin according to the above (1), a plurality of protrusions are provided on the surface of the mold on which the foam parison is sandwiched.

  In the present invention, (3) the second mold is provided with a blade-shaped portion, and the blade-shaped portion is pressed against the surface of the first mold on the side where the foam parison is sandwiched, thereby performing pinch-off. (2) It exists in the manufacturing method of the foaming molding with a skin of description.

  According to the present invention, (4) the first mold and the second mold are each provided with a blade-shaped portion, and the blade-shaped portions are pressed against each other to perform pinch-off. It exists in the manufacturing method of a foam molding with a skin.

  The present invention resides in (5) the foamed molded product with a skin according to any one of the above (1) to (4), wherein the foamed molded product is made of polyolefin and the fiber skin material is made of a nonwoven fabric.

  The present invention resides in (6) the method for producing a foamed molded article with a skin according to any one of the above (1) to (5), wherein air is sucked between the inner walls facing each other in the mold clamping step. .

  The present invention relates to (7) the foamed molded article with a skin according to any one of (1) to (6), wherein air is blown into the split mold from the outlet provided in the split mold in the mold clamping step. Exist in the manufacturing method.

  This invention exists in the manufacturing method of the foaming molding as described in any one of said (1)-(7) whose foaming parison is (8) cylindrical cylindrical foaming parison.

  The present invention is (9) a foam-molded article with a skin obtained by the method for producing a foam-molded article with a skin according to any one of (1) to (8) above, wherein a part of the fiber skin material is It exists in the foaming body with a skin which has penetrate | invaded physically toward the inside from the surface of the foaming body.

In the manufacturing method of the foam-molded body with a skin according to the present invention, the formation of the hollow portion is suppressed by including a mold clamping step for securely bringing the inner wall surfaces facing each other of the foam parison into close contact with each other. For this reason, the foamed molded product with skin obtained by the method for producing the foamed molded product with skin is excellent in strength while maintaining its light weight.
Moreover, in the manufacturing method of the said foam-formed body with a skin, the inner wall surfaces of a foam parison become difficult to leave | separate through a mold-clamping process. For this reason, since it becomes possible to raise a foaming ratio, the whole foaming molding can be made into a sufficient foaming state, and it becomes possible to make it lighter.

In the method for producing a foam-molded article with a skin according to the present invention, the fiber skin material is made to be a foam-molded article while being a simple method by suspending the fiber skin material on the surface of the first mold sandwiching the foam parison. Can be attached to.
Further, by providing a plurality of protrusions on the surface of the second mold on the side where the foam parison is sandwiched, the protrusions serve both as a means for forming a recess on the surface of the foamed molded body with the skin and a means for bringing it into close contact with each other. Thus, it is possible to produce a foamed article with a skin having a recess formed on the surface.

  In the manufacturing method of the foamed article with skin according to the present invention, the second mold is provided with a blade-shaped portion, and the blade-shaped portion is pressed against the surface of the first mold on the side where the foamed parison is sandwiched. When the pinch-off is performed, the fiber skin material is affixed to the foam molded body in a flat shape, and therefore, the fiber skin material is difficult to peel off from the foam molded body.

  In the method for manufacturing a foamed molded article with a skin according to the present invention, the first mold and the second mold are each provided with a blade shape portion, and the blade shape portions are pressed against each other to be pinched off. By doing so, the fiber skin material wraps around the side surface of the foamed molded product, and therefore there is an advantage that the end portion of the fiber skin material is smooth and easy to use.

  In the method for producing a foam-molded article with a skin according to the present invention, when the foam-molded article is made of polyolefin and the fiber skin material is made of a nonwoven fabric, the fiber constituting the nonwoven fabric when the fiber skin material is closely attached to the foamed parison Since it penetrates into the polyolefin, the adhesion strength is further improved. For this reason, a fiber skin material becomes difficult to peel from a foaming molding.

  In the method for producing a foamed article with skin according to the present invention, when the air between the inner walls facing each other in the mold clamping step is sucked, the adhesion between the inner walls facing each other can be improved.

  In the method for producing a foamed molded article with a skin according to the present invention, when air is blown into the split mold from the outlet provided in the split mold in the mold clamping step, the adhesion between the inner wall surfaces facing each other of the foam parison is further improved. Can be improved.

  In the foam-molded article with skin according to the present invention, it is obtained by the above-described manufacturing method, and part of the fiber skin material is physically invaded from the surface of the foam-molded article to the inside, so that it is lightweight. , The strength is excellent.

FIG. 1 is a flowchart showing a method for manufacturing a foamed article with skin according to the first embodiment. FIG. 2 is a partial cross-sectional view showing a die used in the method for manufacturing a foamed article with skin according to the first embodiment. FIG. 3 is a vertical cross-sectional view showing a state in which a cylindrical foam parison is extruded between split molds in the method for manufacturing a foamed molded article with a skin according to the first embodiment. (A) of FIG. 4 is a vertical sectional view showing a state in which the cylindrical foam parison after mold clamping is sandwiched and sealed between the divided molds in the method of manufacturing the foamed article with skin according to the first embodiment, (B) is the vertical sectional view which expanded the part P of (a). FIG. 5 is a horizontal cross-sectional view showing a part of the state after the suction process is performed on the foamed parison body after clamping in the method for producing the foam-formed article with skin according to the first embodiment. (A) of FIG. 6 is a perspective view which shows the foam molding with a skin obtained by the manufacturing method of the foam molding with a skin concerning 1st Embodiment, (b) is the sectional drawing. FIG. 7 is a vertical cross-sectional view showing a state in which a cylindrical foam parison is extruded between split molds in the method of manufacturing a foam-molded article with a skin according to the second embodiment. (A) of FIG. 8 is a vertical sectional view showing a state in which a cylindrical foam parison is sandwiched and sealed in a split mold in the method for manufacturing a foamed molded article with a skin according to the second embodiment, and (b) (A) is the vertical sectional view which expanded the part Q after pressing (a) typically. (A) of FIG. 9 is a perspective view which shows the foaming molding with a skin obtained by the manufacturing method of the foaming molding with a skin which concerns on 2nd Embodiment, (b) is the sectional drawing. FIG. 10 is a cross-sectional view showing a foamed molded product manufactured by a conventional method for manufacturing a foamed molded product with a skin.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

FIG. 1 is a flowchart showing a method for manufacturing a foamed article with skin according to the first embodiment.
As shown in FIG. 1, the method for manufacturing a foamed molded article with a skin according to the first embodiment includes an extrusion step S1 in which a mixed resin containing a foaming agent and a thermoplastic resin is extruded to form a foamed parison; Then, by sandwiching and sealing the fiber skin material with the split mold, the foam parison and the fiber skin material are brought into close contact with each other, and the mold clamping step S2 and the mold clamping step S2 are brought into close contact with the opposing inner wall surfaces of the foam parison. And a suction step S3 for sucking air in the divided mold and reducing the pressure. That is, the extrusion step S1, the mold clamping step S2, and the suction step S3 are performed in this order.

According to the method for producing a foamed product with a skin, it is possible to produce a foamed product with a skin that is lightweight and has excellent strength (no hollow portion is produced).
Hereinafter, each process will be described in more detail.

(Extrusion process)
The extrusion step S1 is a step of extruding a mixed resin containing a foaming agent and a thermoplastic resin from an extrusion port to form a cylindrical cylindrical foam parison.

FIG. 2 is a partial cross-sectional view showing an example of a die used in the method for manufacturing a foam-formed product with skin according to the first embodiment, and FIG. 3 shows a method for manufacturing the foam-formed product with skin according to the first embodiment. It is a vertical sectional view which shows the state by which the cylindrical foam parison was extruded between the split molds.
As shown in FIG. 2, the die 10 includes a die outer cylinder 18, a mandrel 17 disposed substantially at the center of the die outer cylinder 18, a cylindrical space 19 between the die outer cylinder 18 and the mandrel 17, and the cylinder. A ring-shaped piston 12 for pushing the mixed resin stored in the space 19 downward, and an extrusion port (die outlet 11) for discharging the mixed resin.

In the extrusion step S 1, first, a mixed resin, which is a supercritical fluid obtained by mixing a thermoplastic resin and a foaming agent, is kneaded in the die 10 and stored in a cylindrical space 19 between the mandrel 17 and the die outer cylinder 18. Is done. At this time, the amount of the mixed resin to be stored is preferably 5 to 40 liters.
Then, after a predetermined amount of the mixed resin is stored in the cylindrical space 19, the ring-shaped piston 12 is pushed down so that the mixed resin is placed between the die outlet 11 and the divided mold 13 described later as shown in FIG. 3. Extruded into a cylindrical shape, and simultaneously with the extrusion, the mixed resin foams to form a cylindrical foamed parison 20.

In the method of manufacturing the foamed article with skin, since the mixed resin is stored in the cylindrical space 19, the size of the bubble cells is homogenized while the mixed resin is stored. .
Moreover, since the ring-shaped piston 12 pushes out the mixed resin in the die outer cylinder 18 (in-die accumulator method), the vertical distance of the die outlet 11 can be shortened, and the extrusion speed can be increased. it can. For this reason, the state of a bubble cell can be maintained.
The extrusion rate of the mixed resin at this time is preferably 700 kg / hour or more. In this case, a foamed article with a skin having a higher surface smoothness is obtained.

Here, the mixed resin as a starting material will be described.
The mixed resin includes a foaming agent and a thermoplastic resin.

Thermoplastic resins include homopolymers or copolymers of olefins such as ethylene, propylene, butene, isoprene pentene, methyl pentene, polyolefin, polyamide, polystyrene, polyvinyl chloride, polyacrylonitrile, ethylene-ethyl acrylate copolymer Examples thereof include acrylic derivatives such as coalescence, polycarbonates, vinyl acetate copolymers such as ethylene-vinyl acetate copolymers, terpolymers such as ionomers and ethylene-propylene-dienes, ABS resins, polyolefin oxides, and polyacetals. In addition, these may be used individually by 1 type, or may mix and use 2 or more types.
Among these, the thermoplastic resin preferably has a propylene unit, and specifically, is preferably a propylene homopolymer, an ethylene-propylene block copolymer, or an ethylene-propylene random copolymer. .
Further, among these, a propylene homopolymer having a long chain branched structure is particularly preferable. In this case, since melt tension becomes high, it becomes easy to foam and a bubble cell is made more uniform.

  The propylene homopolymer having a long chain branched structure is preferably a propylene homopolymer having a weight average branching index of 0.9 or less. The weight average branching index g ′ is represented by V1 / V2, where V1 is the intrinsic viscosity of the branched polyolefin and V2 is the intrinsic viscosity of the linear polyolefin having the same weight average molecular weight as the branched polyolefin.

  The thermoplastic resin is preferably a polypropylene resin having a melt tension at 230 ° C. in the range of 30 to 350 mN. Here, melt tension means melt tension. When the melt tension is within the above range, the foaming polypropylene resin exhibits strain-hardening properties, and a high foaming ratio can be obtained.

The thermoplastic resin preferably has a melt flow rate (MFR) of 1 to 10 at 230 ° C. Here, MFR is a value measured according to JIS K-7210.
If the MFR is less than 1, it tends to be difficult to increase the extrusion speed as compared with the case where the MFR is in the above range. If the MFR exceeds 10, the MFR is in the above range. In comparison, blow molding tends to be difficult due to the occurrence of drawdown or the like.

  It is preferable to further add a styrene elastomer and / or low density polyethylene to the mixed resin. When a styrene elastomer or low-density polyethylene is added, the impact strength at low temperature of the skin-formed foam-molded product is further improved.

Although it does not specifically limit as a styrene-type elastomer, What is necessary is just an elastomer which has a styrene unit to which hydrogen was added in the molecule | numerator. Examples thereof include hydrogenated elastomers such as styrene-ethylene / butylene-styrene block copolymers, styrene-ethylene / propylene-styrene block copolymers, and styrene-butadiene random copolymers.
The blending ratio of the styrenic elastomer is preferably in the range of less than 40 wt% with respect to the thermoplastic resin from the viewpoint of moldability.
In addition, the content of styrene in the styrene-based elastomer is preferably less than 30 wt%, more preferably less than 20 wt%, from the viewpoint of impact strength at low temperatures.

As the low density polyethylene, those having a density of 0.91 g / cm ³ or less are suitably used from the viewpoint of impact strength at low temperatures. In particular, it is preferable to use linear ultra-low density polyethylene polymerized by a metallocene catalyst.
The blending ratio of the low density polyethylene is preferably in the range of less than 40 wt% with respect to the thermoplastic resin from the viewpoint of rigidity and heat resistance.

  In addition to styrene elastomers, low-density polyethylene and foaming agents, mixed resins include silica, mica, talc, calcium carbonate, glass fibers, carbon fibers and other inorganic fillers, nucleating agents, colorants, plasticizers, stabilizers, An antistatic agent, a flame retardant, a foaming agent, or the like may be added.

Examples of the foaming agent include inorganic foaming agents such as air, carbon dioxide gas, nitrogen gas, and water, or organic foaming agents such as butane, pentane, hexane, dichloromethane, and dichloroethane.
Among these, it is preferable to use air, carbon dioxide gas or nitrogen gas as the foaming agent. In this case, there is no mixing of organic substances, and there is no decrease in durability or the like.

  Moreover, it is preferable to use a supercritical fluid as the foaming method. In particular, it is preferable that carbon dioxide gas or nitrogen gas is in a supercritical state to foam the mixed resin. In this case, it can foam uniformly and reliably. The nitrogen supercritical fluid is obtained by setting nitrogen to a critical temperature of 149.1 ° C. and a critical pressure of 3.4 MPa or more, and the carbon dioxide supercritical fluid is carbon dioxide to a critical temperature of 31 ° C. and a critical pressure. It is obtained by setting it to 7.4 MPa or more.

(Clamping process)
The mold clamping step S2 is a step of sealing the extruded cylindrical foam parison and the fiber skin material by sandwiching them with a split mold. As a result, the cylindrical foam parison and the fiber skin material are brought into close contact with each other, and the inner wall surfaces facing each other of the cylindrical foam parison are brought into close contact with each other.

FIG. 3 is a vertical cross-sectional view showing a state in which a cylindrical foam parison is extruded between split molds in the method for manufacturing a foamed molded article with a skin according to the first embodiment.
As shown in FIG. 3, in the method for manufacturing a foamed molded article with a skin according to the first embodiment, the split mold 13 includes a left mold 13 a (first mold) and a right mold 13 b (second mold). The cylindrical foam parison 20 is extruded between the left mold 13a and the right mold 13b.

  The left mold 13a is provided with a hooking portion 25 on the upper surface 23a on the side where the cylindrical foam parison 20 is sandwiched, and by hooking the end of the fiber skin material 21 on the hooking portion 25, the fiber skin The material 21 is suspended. In addition, the surface 23a is a flat surface. For this reason, when sandwiching the cylindrical foam parison 20 via the fiber skin material 21, it is possible to suppress the occurrence of wrinkles or the like in the fiber skin material 21 with a simple method.

On the other hand, the right mold 13b is provided with blade portions 24 on the upper and lower sides of the surface 23b on the side where the cylindrical foam parison 20 is sandwiched, and the portion sandwiched between the upper and lower blade portions 24 is foamed with a skin later. Become a body.
The right mold 13b is provided with a plurality of protrusions 23 on a surface 23b on the side where the cylindrical foam parison 20 is sandwiched.

  In the mold clamping step S2, the core provided at the tip of the die 10 is provided with a suction port 15a (see FIG. 3), and between the inner wall surfaces of the cylindrical foam parison 20 facing from the suction port 15a, that is, Air in the cylindrical foam parison is sucked. Thereby, the adhesiveness of the inner wall surfaces which the cylindrical foam parison 20 faces can be improved more.

  In the mold clamping step S2, air is blown into the right mold 13b from the air outlet 27 provided in the divided mold 13. Thereby, since the air pressure in the sealed space in the right mold 13b is increased, the adhesion between the inner wall surfaces facing each other of the cylindrical foam parison 20 is further improved. That is, the portion not sandwiched between the protrusions 23 is brought into close contact with the air pressure. In addition, it is preferable that the pressure which blows in air at this time is a pressure of 0.05-0.15 MPa from a viewpoint of the shape maintenance of a bubble cell. From the viewpoint of preventing cooling of the foam parison, the temperature of the blown air is preferably higher than the temperature of the foam parison.

(A) of FIG. 4 is a vertical sectional view showing a state in which the cylindrical foam parison after mold clamping is sandwiched and sealed between the divided molds in the method of manufacturing the foamed article with skin according to the first embodiment, (B) is the vertical sectional view which expanded the part P of (a).
As shown in FIG. 4A, in the mold clamping step S <b> 2, the cylindrical foam parison 20 is sandwiched between the divided molds 13, so that the protrusions 23 provided on the right mold 13 b are formed on the cylindrical foam parison 20. Press the outer wall surface. Thereby, it becomes the foaming parison body 30 in which the inner wall surfaces facing each other of the cylindrical foaming parison 20 are in close contact with each other. At the same time, the foamed parison body 30 and the fiber skin material 21 are brought into close contact with each other. At this time, the foamed parison body 30 enters inward from the surface of the fiber skin material 21, and the anchoring effect is exhibited.

  According to the above method for producing a foam-formed product with a skin, the protrusion 23 of the right mold 13b serves as a means for forming a recess on the surface of the foam-formed product with a skin and a means for bringing it into close contact. It becomes possible to produce a foamed molded article with a skin in which concave portions are formed.

  Further, as shown in FIG. 4B, the upper blade portion 24 of the right mold 13b is pressed against the surface 23a on the side of sandwiching the cylindrical foam parison 20 of the left mold 13a. Thereby, pinch-off is given to the foam parison body 30 and the fiber skin material 21. For this reason, in the foamed molded body with skin obtained, the fiber skin material 21 is affixed to the foam molded body in a flat shape, so that the fiber skin material 21 is difficult to peel off.

Here, as the material of the fiber skin material 21, synthetic fibers such as polyester, polypropylene, polyamide, polyurethane, acrylic and vinylon, semi-synthetic fibers such as acetate and rayon, recycled fibers such as viscose rayon and copper ammonia rayon, cotton Natural fibers such as hemp, wool, silk, etc., glass fibers, carbon fibers, or blended fibers thereof.
Among these, it is preferable that the raw material of the fiber skin material 21 is a polypropylene or polyester from a viewpoint of a touch feeling, durability, and a moldability.

  The yarn used for the fiber skin material 21 is, for example, polyester: (3-5) denier x (50-100) mm, etc., a fineness of 3-15 denier, a staple spun yarn having a fiber length of about 2-5 inches Polyester in a bundle of thin flexible filaments: multifilaments of about 5 denier × (about 30 to 200) = about 150 to 1000 denier / 1, or thick polyester such as polyester: 400 to 800 denier / 1 -It is preferable to use in combination with a filament.

Examples of the structure of the fiber skin material 21 include non-woven fabrics, woven fabrics, knitted fabrics, and fabrics obtained by raising them. The woven fabric includes not only a plain structure in which the woven structure is tangled up and down in order, but also various changed woven forms in which some yarns are entangled and jumped.
Among these, the structure of the fiber skin material 21 is preferably a non-woven fabric because it has no directionality with respect to elongation, is easily formed into a three-dimensional shape, and is excellent in surface touch and texture.

  Particularly, when the cylindrical foam parison 20 is made of polyolefin and the fiber skin material 21 is made of a nonwoven fabric, when the fiber skin material 21 is brought into close contact with the cylindrical foam parison, the fibers constituting the nonwoven fabric enter the polyolefin. The sticking strength is further improved. For this reason, it becomes difficult for the fiber skin material 21 to peel off from the foaming molding which the cylindrical foaming parison hardened | cured.

From these things, it is more preferable that the fiber skin material 21 is a polypropylene nonwoven fabric or a polyester nonwoven fabric.
In this case, since the fiber skin material 21 itself is thermoplastic, it can be used for another purpose by being heated and deformed after separation and collection.

Here, in the manufacturing method of the foam-molded body with skin, when the fiber skin material 21 is a polypropylene nonwoven fabric, the foam-molded body and the fiber skin material 21 are the same material, which facilitates recycling.
On the other hand, if the fiber skin material 21 is a polyester nonwoven fabric, the melting point between the foam molded body and the fiber skin material 21 is different. Therefore, when the fiber skin material 21 is bonded to the foam molded body, it is altered or deformed by heat, or is correct. Generation | occurrence | production of malfunctions, such as being unable to adhere | attach on a position, can be suppressed. In this case, the moldability, rigidity, appearance and durability are also excellent.

In the manufacturing method of the foam-equipped body with a skin according to the first embodiment, the formation of the hollow portion is suppressed by applying the mold clamping step S2 that securely contacts the inner wall surfaces facing each other of the cylindrical foam parison 20. For this reason, the foam-molded body with skin obtained by the method for producing the foam-molded body with skin has excellent strength such as impact resistance while maintaining its light weight.
Moreover, in the manufacturing method of the said foam-formed body with a skin, inner wall surfaces become difficult to leave | separate by passing through mold clamping process S2. For this reason, since it becomes possible to raise a foaming ratio, the whole foamed molding with a skin can be made into a sufficient foaming state, and it becomes possible to make it lighter.

(Suction process)
The suction step S3 is a step of sucking and depressurizing the air in the divided mold 13 in a state where the cylindrical foam parison 20 is sealed between the divided molds 13 after the mold clamping step S2.

FIG. 5 is a vertical cross-sectional view showing a part of the state after subjecting the foamed parison body after mold clamping to the suction step in the method of manufacturing the foamed molded body with skin according to the first embodiment.
As shown in FIG. 5, in the suction step S <b> 3, the air in the split mold 13 is sucked from the air outlet 27 provided in the split mold 13. That is, the fiber skin material 21 and the foamed parison body 30 are pressed by the projections 23 of the right mold 13b, and the pressure in the sealed space in the divided mold 13 is lowered while maintaining the state of being in close contact with each other.
Thereby, the foam parison body 30 is swelled to the outlet 27 side, and bubbles grow along with this, and the volume of the foam parison body 30 increases.

At this time, particularly when the fiber skin material 21 is a nonwoven fabric, when the foam parison body 30 flows due to swelling, the fibers on the surface of the nonwoven fabric also move simultaneously. The wearing strength is further improved.
And by making it cool and solidify, a foaming molding with a skin is obtained.

(A) of FIG. 6 is a perspective view which shows the foam molding with a skin obtained by the manufacturing method of the foam molding with a skin concerning 1st Embodiment, (b) is the sectional drawing.
As shown to (a) of FIG. 6, the foaming molding 40 with a skin consists of the foam molding 31 by which the recessed part was formed in the surface, and the fiber skin material 21 stuck on the back surface of the foam molding 31. .
At this time, in the foamed molded product 40 with a skin, a part of the fiber skin material 21 physically penetrates from the surface of the foamed molded product 31 toward the inside (not shown). For this reason, strength is excellent.

  Moreover, as shown in FIG. 6B, the foamed molded body 40 with the skin is filled with the thermoplastic resin to the inside, and no hollow portion is generated. For this reason, it is lightweight and excellent in strength.

  The skin foamed molded product 40 has a closed cell structure including a plurality of cell cells. Here, the closed cell structure is a structure having a plurality of bubble cells, and means a structure having at least 50% of closed cells. Therefore, the surface smoothness is excellent.

The bubble cell preferably has an average bubble diameter of less than 1000 μm, and more preferably less than 500 μm. Here, the average bubble diameter means an average value of the maximum diameters of many bubbles.
When the average bubble diameter is 1000 μm or more, the surface roughness tends to be large and the surface smoothness tends to be inferior compared with the case where the average bubble diameter is within the above range.

  The foamed molded product 40 with a skin is a highly foamed molded product having a foaming ratio of 3.0 to 20 times. Here, the expansion ratio is a value obtained by dividing the density of the thermoplastic resin by the apparent density of the foamed article with skin.

In the foamed molded product 40 with skin, the peel strength of the fiber skin material 21 from the foamed molded product 31 at a temperature of 25 ° C. is 50 N / 25 mm width or more, and preferably 80 N / 25 mm width or more. In addition, the value of the said peeling strength is measured based on JIS-K-7113.
When the peel strength is 50 N / 25 mm width or more, it is difficult to remove even with the force of a normal adult male, and it is possible to obtain a foamed product 40 with a skin having excellent peel resistance.
In particular, when applied to a curved floor board for automobiles, the durability as a curved floor board can be sufficiently satisfied when the peel strength is 50 N / 25 mm width or more, preferably 80 N / 25 mm width or more.

In the foamed molded product 40 with skin, the peel strength of the fiber skin material 21 from the foamed molded product 31 at a temperature of 150 ° C. is 10 N / 25 mm width or less, and preferably 5 N / 25 mm width or less.
When the peeling strength is 10 N / 25 mm width or less, peeling can be easily performed without generating a residue. Therefore, mechanical work or human work for separating and collecting members of different materials can be easily performed. Is called.

In the foamed molded product 40 with skin, the basis weight of the fiber skin material 21 is preferably 100 to 500 g / m ² and more preferably 150 to 500 g / m ² from the viewpoints of three-dimensional shape reproducibility and moldability. More preferred. The weight per unit area is a value obtained by measuring a weight of 10 cm ² with a direct balance and converting it to a weight per 1 m ² .

From the viewpoint of three-dimensional shape reproducibility and moldability, the tensile strength of the fiber skin material 21 is preferably 15 kg / cm ² or more, and the elongation is preferably 30% or more. The values of tensile strength and elongation are measured at a temperature of 20 ° C. according to JIS-K-7113.

The foamed molded product 40 with a skin is suitably used as a foamed plate material. Specifically, the flexural rigidity for automobiles, aircrafts, vehicles / marine vessels, building materials, housings of various electric devices, sports / leisure or the like Used for structural members that are resistant to bending buckling.
Especially when used as automotive structural members such as cargo floor boards, deck boards, rear parcel shelves, roof panels, door trims, interior panels, door inner panels, platforms, hardtops, sunroofs, bonnets, bumpers, floor spacers, devia pads, etc. Since the weight of an automobile can be measured, fuel efficiency is improved.

[Second Embodiment]
2nd Embodiment of the manufacturing method of the foaming molding with a skin which concerns on this invention is described.
The method for manufacturing the foam-molded body with skin according to the second embodiment is the same as the method for manufacturing the foam-molded body with skin according to the first embodiment, except that the split mold 53 is different.

FIG. 7 is a vertical cross-sectional view showing a state in which a cylindrical foam parison is extruded between split molds in the method of manufacturing a foam-molded article with a skin according to the second embodiment.
As shown in FIG. 7, in the method of manufacturing the foamed molded article with skin according to the second embodiment, the split mold 53 includes a left mold 53 a and a right mold 53 b, and the cylindrical foam parison 20 is It is extruded between the left mold 53a and the right mold 53b.

  The left mold 53a is provided with blade portions 54a above and below a surface 63a on the side sandwiching the cylindrical foam parison 20, and a hook portion 55 is provided further above the upper blade portion 54a. . Then, the fiber skin material 21 is suspended by hooking the end of the fiber skin material 21 on the hook portion 55. That is, the fiber skin material 21 is suspended so as to cover the blade-shaped portion 54a. In addition, the surface 63a is a flat surface. For this reason, when the cylindrical foam parison 20 is sandwiched through the fiber skin material 21, it is possible to prevent wrinkles from occurring on the fiber skin material 21 with a simple method.

On the other hand, the right mold 53b is provided with blade portions 54b on the upper and lower sides, respectively, and the portion sandwiched between the upper and lower blade portions 54b later becomes a foamed article with skin.
Further, the right mold 53b is provided with a plurality of protrusions 63 on a surface 63b on the side where the cylindrical foam parison 20 is sandwiched.

(A) of FIG. 8 is a vertical sectional view showing a state in which a cylindrical foam parison is sandwiched and sealed in a split mold in the method for manufacturing a foamed molded article with a skin according to the second embodiment, and (b) (A) is the vertical sectional view which expanded the part Q after pressing (a) typically.
As shown in FIG. 8A, in the mold clamping process, the cylindrical foam parison 20 is sandwiched between the split molds 53 so that the protrusions 63 provided on the right mold 13b are outside the cylindrical foam parison 20. The wall surface is pressed to form a foamed parison body 30 in which the inner wall surfaces facing each other of the cylindrical foam parison 20 are in close contact with each other. At the same time, the foamed parison body 30 and the fiber skin material 21 are adhered (attached).

  According to the above method for producing a foamed product with skin, the protrusion 63 of the right mold 53b serves as both a concave portion forming means on the surface of the foamed product with skin and a means for bringing it into close contact with the surface. It becomes possible to produce a foamed molded article with a skin in which concave portions are formed.

  Further, as shown in FIG. 8B, the blade shape portion 54a of the left mold 53a and the blade shape portion 54b of the right mold 53b are pressed against each other. Thereby, pinch-off is given to the foam parison body 30 and the fiber skin material 21. For this reason, in the foam-molded body with skin obtained, the fiber skin material 21 wraps around the side surface of the foam-molded body, so that there is an advantage that the end portion of the fiber skin material is smooth and easy to use.

  And like the manufacturing method of the foam-molded body with skin according to the first embodiment, the foam-molded body with skin is obtained by cooling and solidifying through the suction step S3 (see FIG. 9).

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment.

For example, in the manufacturing method of the foam-molded body with skin according to the first and second embodiments, the foam-molded body with skin is manufactured using a cylindrical foam parison, but with the skin according to other embodiments. In the manufacturing method of a foaming molding, you may use several (for example, 2 sheets) sheet-like foaming parison.
In this case, the method for producing a foamed molded article with a skin includes an extrusion step of extruding a mixed resin containing a foaming agent and a thermoplastic resin to form a sheet-like foamed parison, a plurality of sheet-like foamed parisons, and a fiber skin material. After the sheet-shaped foam parison and the fiber skin material are brought into intimate contact with each other by being sandwiched between the divided molds, and the mold-clamping process in which the inner wall surfaces facing each other in the sheet-form foam parison are in close contact with each other and the mold-clamping process are performed. And a suction step of sucking and reducing the pressure of the air in the divided mold.

  Moreover, it is not limited to the case where the extruded foam parison is directly conveyed between divided molds and molded, and after extrusion, the foam parison is cooled and solidified to form a foam parison molded body, and then the foam parison molded body is reheated. Alternatively, the foamed parison may be returned and conveyed between the divided molds to be molded.

In the manufacturing method of the foamed article with skin according to the first embodiment, the air between the inner wall surfaces of the foam parison facing each other is sucked in the adhesion step, but this is not essential.
In the mold clamping process, air is blown into the split mold from the outlet provided in the split mold, but it is not essential.

  The foam-molded article with skin obtained by the method for producing a foam-molded article with skin according to the present invention is suitably used as a foamed plate material, specifically for automobiles, aircraft, vehicles / ships, building materials, various It is used for structural members that are strong in bending rigidity or bending buckling for housing of electric equipment, sports and leisure. Such a foam-formed product with a skin is excellent in strength while being lightweight.

DESCRIPTION OF SYMBOLS 10 ... Die 11 ... Die exit 12 ... Ring-shaped piston 13, 53 ... Split mold 13a, 53a ... Left mold (1st mold)
13b, 53b ... Right mold (second mold)
15a ... Suction port 17 ... Mandrel 18 ... Die outer cylinder 19 ... Cylindrical space 20 ... Cylindrical foam parison 21 ... Fiber skin material 23, 63 ... Protrusions 23a, 23b , 63 a, 63 b... Surface 24, 54 a, 54 b... Blade shape part 25, 55... Hook part 27 .. outlet 30 ... foamed parison body 31. 50 ... Foamed molded body with skin 51 ... Hollow part S1 ... Extrusion process S2 ... Clamping process S3 ... Suction process

Claims (9)

A method for producing a foamed molded product with a skin comprising a foamed molded product and a fiber skin material adhered to one surface of the foamed molded product,
Extruding a mixed resin containing a foaming agent and a thermoplastic resin to form a foamed parison;
A mold in which the foam parison and the fiber skin material are sealed by sandwiching the foam parison and the fiber skin material with a split mold so that the foam parison and the fiber skin material are in close contact with each other, and the inner wall surfaces facing the foam parison are completely in close contact with each other. The fastening process;
After the mold clamping step is performed, a suction step of sucking air in the split mold to reduce the pressure and increasing the volume of the foam parison ;
A method for producing a foamed molded article with a skin. The split mold comprises a first mold and a second mold;
The fiber skin material is suspended from the surface of the first mold on the side sandwiching the foamed parison,
The manufacturing method of the foam-molded article with a skin according to claim 1, wherein a plurality of protrusions are provided on a surface of the second mold on the side sandwiching the foam parison. The second mold is provided with a blade portion,
The method for producing a foamed article with a skin according to claim 2, wherein pinching off is performed by pressing the blade-shaped part against a surface of the first mold on the side where the foam parison is sandwiched. Each of the first mold and the second mold is provided with a blade portion,
The method for producing a foamed article with skin according to claim 2, wherein pinching off is performed by pressing the blade-shaped parts together.   The foamed molded product with a skin according to any one of claims 1 to 4, wherein the foamed molded product is made of polyolefin, and the fiber skin material is made of a nonwoven fabric.   The method for producing a foamed molded article with a skin according to any one of claims 1 to 5, wherein air between the inner wall surfaces of the foam parison facing each other is sucked in the mold clamping step.   The manufacturing method of the foam molding with a skin | cover as described in any one of Claims 1-6 which blows air in the said division mold from the blower outlet provided in the said division mold in the said mold clamping process.   The said foaming parison is a cylindrical cylindrical foaming parison, The manufacturing method of the foaming molding as described in any one of Claims 1-7. A foam-molded article with a skin obtained by the method for producing a foam-molded article with a skin according to any one of claims 1 to 8,
A foam-molded article with a skin, in which part of the fiber skin material is physically invaded from the surface of the foam-molded article toward the inside.

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