JP5604997B2 - Manufacturing method of resin laminate having inner rib - Google Patents

Description

The present invention relates to a method for manufacturing a resin laminate having an inner rib, and more specifically, a resin having an inner rib capable of achieving weight reduction and high rigidity while ensuring manufacturing efficiency and aesthetic appearance. The present invention relates to a method for manufacturing a laminate.

Conventionally, so-called resin laminates have been used as interior materials, building materials, logistics and packaging materials for automobiles.
As an example of a resin laminated board, it has a resin-made surface material and a resin-made back material, and the back material is provided with a plurality of recesses whose leading ends are abutted against the inner surface of the surface material. In particular, in the case of automobile interior materials and building materials where the appearance is important, a decorative material such as a nonwoven fabric is attached to the front side of the surface material.
According to such a resin laminate, although it is possible to increase the compression rigidity in the thickness direction of the laminate through the ribs constituting the recesses, there are the following technical problems.
First, the bending rigidity of the laminated board tends to be insufficient compared to the compression rigidity in the thickness direction of the laminated board. More specifically, an opening is formed in the outer surface of the back material according to the number of recesses by the recess provided in the back material. Bending rigidity tends to deteriorate as compared with the case where there is no.

Second, the appearance is inferior due to the provision of the recess. More specifically, unlike the surface material, it is difficult to attach a cosmetic material to the outer surface of the back surface material due to the formation of a plurality of openings on the outer surface of the back surface material as described above. Since the plurality of openings are exposed in appearance, the appearance of the outer surface of the back material is inferior to that in the case where no opening is provided.
In this respect, a resin laminated plate is employed in which a rib is provided between the front surface material and the back surface material without forming such a recess.
In this resin laminate, plate-like ribs are provided between the surface material and the back material, and are spaced apart from each other in the direction of one side of the laminate and extending in the direction of the other side. In each outer surface, no opening is formed.
As a method for producing such a resin laminate, an extrusion molding technique is well known. By preparing a slit shape according to the arrangement of the ribs, the molten resin is extruded from the slit, thereby obtaining a uniform cross-sectional shape. Thus, it is possible to manufacture a resin laminate in which the ribs extend in the extrusion direction.
However, the following technical problems exist in the resin laminate using such an extrusion technique.
That is, the production efficiency of a resin laminate having an excellent appearance is low.
More specifically, the portions located at both ends of the slits of the extruded resin laminate expose the internal structure and require separate end treatment from the viewpoint of aesthetic appearance. descend.
Furthermore, when sticking a cosmetic material on the outer surface of the surface material, a separate sticking step for the cosmetic material is required after the extrusion step, and thus the production efficiency is further reduced.
As a method for manufacturing a resin laminate without causing such a decrease in manufacturing efficiency, for example, Patent Document 1 discloses a manufacturing method using blow molding technology.
This method of manufacturing a resin laminate is intended for forming an inner rib between a front surface material and a back surface material using a split mold having one slide core for a parison of a thermoplastic resin. is there.

More specifically, a step of disposing a decorative material between the cavity of one mold of the pair of split molds and the parison of the thermoplastic resin, and clamping the pair of split molds, thereby pinching off the part. The inside of the parison of the thermoplastic resin is formed in a sealed state, and the slide core provided on the other mold is protruded toward one mold, thereby facing the other mold of the parison of the thermoplastic resin. A step of projecting the back material part into a U shape so that the tip of the back material is welded to the inner surface of the front surface material facing one mold of the thermoplastic resin parison; and the slide core of the other mold By retracting toward the cavity and applying blow pressure to the sealed part formed inside the parison, the decorative material is welded to the outer surface of the front material, and the slide core of the protruding back material part By welding together the opposed faces which are opposed to each other with, and a step of forming an integral inner ribs.

According to such a manufacturing method, welding with the surface material of the decorative material is not performed by mold clamping, but is performed by a blow pressure smaller than the mold clamping force, whereas the rib is formed as a rib through the concave portion as in the prior art. The inner rib is formed without forming by mold clamping, and when the inner rib is formed, the pressing force against the inner surface of the base material at the tip of the rib is kept low. Maintains the appearance.
However, this manufacturing method has the following technical problems.
That is, it is difficult to achieve a high rigidity, particularly an increase in bending rigidity, while ensuring the weight reduction of the resin laminate.

More specifically, in order to ensure bending rigidity, if the inner ribs are arranged densely by narrowing the pitch interval of the inner ribs, the thickness of the back surface material in which the parison is stretched and the inner ribs are provided. Thinning of the wall is caused. In particular, when resin laminates are used for applications that require high bending rigidity, in order to maintain the weldability between the tip of the inner rib and the inner surface of the surface material in each inner rib, the viewpoint of securing the welding area Therefore, it is necessary to secure the thickness of the tip end portion of the inner rib, and this further causes the thickness of the back surface material to be reduced.
On the other hand, since the cylindrical parison is usually extruded from the annular slit between the die cores, its thickness is substantially uniform in the circumferential direction, while when a pair of split molds are clamped, Since the blowing pressure is applied from the sealed space in the mold, the pressing force of the parison against the mold is uniform over the entire surface of the parison.
From this point, the thickness of the cylindrical parison needs to be set in accordance with the thin part of the back material provided with the inner rib on the side of one mold, whereby the surface material on the side of the other mold is An excessively thick sheet is formed.
As described above, when a cylindrical parison having a substantially uniform wall thickness in the circumferential direction is used to form the inner rib, an inevitably difference in thickness occurs between the back material and the surface material after blow molding. As a result, it is impossible to achieve sufficient weight reduction and thinning of the resin laminate.
Japanese Patent No. 3791924

SUMMARY OF THE INVENTION In view of the above technical problems, an object of the present invention is to provide a method for producing a resin laminate having an inner rib capable of achieving weight reduction and high rigidity while ensuring production efficiency and appearance. There is to do.

In order to solve the above problems, a method for producing a resin laminate having an inner rib according to the present invention is as follows.
A pair of split molds in which a slide core that can be moved back and forth with respect to the other mold is provided in the cavity of one mold, and two molten thermoplastic resin sheets each adjusted in thickness And the stage of preparing
Positioning two molten thermoplastic resin sheets between a pair of split molds in a form that protrudes around an annular pinch-off portion provided in each mold at a predetermined interval from each other; ,
Forming a sealed space between one thermoplastic resin sheet facing the mold cavity and the mold cavity;

While sucking the sealed space from one mold side, the outer surface of one thermoplastic resin sheet is made to protrude from the cavity of one mold by projecting the slide core toward the other mold. By pressing, shaping one thermoplastic resin sheet and projecting a part of one thermoplastic resin sheet in a U-shape toward the other mold; and
Butt welding a part of one thermoplastic resin sheet to the inner surface of the other thermoplastic resin sheet; and
Clamping a pair of molds to weld the peripheral edges of two molten thermoplastic resin sheets to form a sealed portion inside the two molten thermoplastic resin sheets When,
By retracting the slide core toward one mold, the inner surfaces of some of the one thermoplastic resin sheet protruding in a U shape are opposed to each other;
And applying a blow pressure from the inside of the sealed portion to weld the opposed inner surfaces together to form an inner rib.

  According to the method for manufacturing a resin laminate having an inner rib having the above-described configuration, a recess is provided on the outer surface of one thermoplastic resin sheet so that the rib is not provided but provided on one mold. By forming the inner rib using the slide core, it is possible to maintain the aesthetic appearance without providing an opening on the outer surface of one of the thermoplastic resin sheets, in particular by providing a plurality of inner ribs. It is possible to secure bending rigidity by narrowing the interval between the matching inner ribs, and at the same time, the peripheral edges of two molten thermoplastic resin sheets are welded together by clamping a pair of molds. This eliminates the need for a separate end face treatment as in the prior art, and improves the manufacturing efficiency.

At that time, after positioning the two thermoplastic resin sheets each adjusted in thickness between the divided molds, a sealed space is formed between one resin sheet and the cavity of the mold opposite thereto. By forming and sucking the sealed space from the mold side, according to conventional blow molding, a cylindrical parison is used to shape into a shape along the cavity by blowing pressure. Since the slide core is provided only in the cavity, the parison is greatly stretched on the cavity side having the slide core, but on the cavity side not having the slide core, the parison is not stretched relatively and the respective thicknesses are different. However, by resolving these problems, two resin sheets were used to the extent that required strength was ensured. It is possible to thin to individually maximize bets respective thicknesses, while thereby ensuring the production efficiency and product quality, a sufficient weight reduction, thinning can be achieved.

The step of forming the inner rib may include a step of applying a blow pressure from the inside of the sealed portion while retracting the slide core toward one mold.
Furthermore, the positioning step of the two thermoplastic resin sheets includes a step of disposing a decorative material between the cavity of the other mold and the other thermoplastic resin sheet,
The butt welding step of the one thermoplastic resin sheet has a step of welding the decorative material to the other thermoplastic resin sheet with a butt pressure that does not leave a pressing mark on the surface of the decorative material. Good.
Furthermore, the step of forming the inner rib may further include a step of welding the decorative material to the other thermoplastic resin sheet.
In addition, it is preferable to have a step of extruding between a pair of split molds in a form in which the melted sheet-like two parisons hang downward.
Furthermore, a plurality of the slide cores are provided at predetermined intervals in the vertical direction according to the bending rigidity required for the resin laminate, and each slide core extends in the horizontal direction across the cavity of one mold. It is good to be provided.
Furthermore, the suction step includes a step of moving an outer frame that is externally fitted to a peripheral edge of the one mold so as to be movable in a clamping direction toward the outer surface of the one thermoplastic resin sheet, A sealed space may be formed by the outer surface of the one thermoplastic resin sheet, the inner peripheral surface of the outer frame, and the cavity of the one mold.
In addition, a pair of molds are clamped to bring the pinch-off portions into contact with each other, thereby welding the peripheral edges of two molten thermoplastic resin sheets to form a parting line, It is preferable to form a sealed hollow portion between two molten thermoplastic resin sheets.

An embodiment of a method for producing a resin laminate 100 according to the present invention will be described below in detail with reference to the drawings, taking a resin laminate for a vehicle interior product as an example.
As shown in FIG. 1, the resin laminate 100 is composed of a front sheet 120A, a back sheet 120B, and a decorative material sheet 140 bonded to the outer surface 150 of the front sheet 120A. The resin laminated plate 100 has a three-layer laminated structure of a decorative material sheet 140, a front side sheet 120A, and a back side sheet 120B.
As shown in FIG. 1, a sealed hollow portion 280 is formed between the front surface side sheet 120 </ b> A and the back surface side sheet 120 </ b> B, and the sealed hollow portion 280 is formed on the back surface of the laminated structural plate 100. It is closed by the outer peripheral wall of the side sheet 120B to constitute a hollow double wall structure. In addition, the decorative material sheet 140 is affixed so that it may reach the surrounding wall 130 of a hollow double wall structure, and, thereby, the external appearance is maintained.
Each thickness (thickness) of the front side sheet 120 </ b> A and the back side sheet 120 </ b> B and the overall thickness (plate thickness) as the vehicle interior product 100 may be appropriately determined according to the use of the vehicle interior product 100. Good. From the viewpoint of lightness, the wall thickness is 1.5 mm or less, preferably 1.0 mm or less, and the plate thickness is 15 mm or less, preferably 10 mm or less.

The resin laminated plate 100 is formed with a plurality of inner ribs 122 extending between the inner surface 180 of the back sheet 120B and the inner surface 170 of the front sheet 120A. The plurality of inner ribs 122 extend along the other side of the rectangle at a predetermined interval along the direction of one side of the rectangle of the resin laminate 100. As will be described in detail later, the resin laminate 100 is manufactured by blow-molding a thermoplastic resin. At this time, each of the plurality of inner ribs 122 covers a part of the back-side sheet 120B. The sheet 120 </ b> A protrudes toward the inner surface 170 and is butt welded to the inner surface 170, whereby the back side sheet 120 </ b> B and the front side sheet 120 </ b> A are formed by a plurality of inner ribs 122. It is possible to be integrated and ensure rigidity or strength. In particular, when the plurality of inner ribs 122 ensure the compressive rigidity in the thickness direction of the resin laminate 100 and when the ribs are formed by providing recesses as in the prior art, the recesses are provided on one sheet. As a result, an opening was formed, and the bending rigidity in the direction of expanding the opening was deteriorated. However, since such an opening is not formed on the outer surface of the back surface side sheet 120B of the resin laminate 100, the appearance is beautiful. In addition to ensuring, it is also possible to prevent deterioration of bending rigidity.

The thickness of each of the plurality of inner ribs 122 or the interval between adjacent ribs may be determined according to the required compression rigidity or bending rigidity. However, as will be described later, each of the plurality of inner ribs 122 is provided on the back side. A part of the sheet 120B is projected in a U shape toward the inner surface 170 of the front side sheet 120A, and a part of the protruding back side sheet 120B facing each other is welded. The thickness of each of the plurality of inner ribs 122 is approximately twice the thickness of the back surface side sheet 120B. From this point, in consideration of the influence of the thickness of the inner rib 122 and the interval between adjacent ribs on the rigidity while securing the welding area from the viewpoint of the weldability of the inner rib 122 to the front side sheet 120A, What is necessary is just to adjust the thickness of the thermoplastic resin sheet which is the material of the back surface sheet 120B which is the object of blow molding, independently of the thermoplastic resin sheet which is the material of the front surface sheet 120A.

As will be described later, the back side sheet 120B clamps the two divided molds 50 with the two thermoplastic resin sheets P in a molten state positioned between the two divided molds 50. When it shape | molds by it, according to the use of the laminated board 100, it has the sealing hollow part 280 in the desired position between the front surface sheet 120A and the back surface sheet 120B, and it exhibits a desired surface shape. And providing the laminate 100 capable of realizing the outer shape or the surface shape and the internal structure according to the intended use of the laminate 100 by welding the front side sheet 120A and the back side sheet 120B. Is possible. In particular, the parting line PL is formed by the peripheral surfaces of the front side sheet 120A and the back side sheet 120B being welded to each other.

Next, an apparatus for forming such a laminated plate 100 will be described below.

As shown in FIG. 2, the molding device 10 for the laminated plate 100 includes an extrusion device 12 and a mold clamping device 14 disposed below the extrusion device 12, and the molten heat extruded from the extrusion device 12. The plastic resin sheet P is sent to the mold clamping device 14, and the molten thermoplastic resin sheet P is molded by the mold clamping device 14. Here, since the apparatuses for extruding each of the two thermoplastic resins and sending them to the mold clamping device 14 are the same, only one of them will be described, and the other will be given the same reference number for the description. Omitted.

The extruding device 12 is a conventionally known type, and a detailed description thereof is omitted. However, a cylinder 18 provided with a hopper 16, a screw (not shown) provided in the cylinder 18, and a screw are connected to the screw 18. The hydraulic motor 20, an accumulator 22 that communicates with the inside of the cylinder 18, and a plunger 24 provided in the accumulator 22, and a resin pellet introduced from the hopper 16 is screwed into the cylinder 18 by the hydraulic motor 20. The molten resin is melted and kneaded by the rotation of the resin, and the molten resin is transferred to the accumulator chamber 22 and stored in a certain amount. The plunger 24 is driven to feed the molten resin toward the T-die 28 and through the extrusion slit 34 to a predetermined length. A continuous thermoplastic resin sheet P is extruded and arranged at intervals. While being pressed between the rollers 30 is suspended between the split mold 32 is fed downward. Thereby, as will be described in detail later, the thermoplastic resin sheet P is disposed between the split molds 32 in a state of having a uniform thickness in the vertical direction (extrusion direction).

The extrusion capability of the extrusion device 12 is appropriately selected from the viewpoint of the size of the resin molded product to be molded, the draw-down of the thermoplastic resin sheet P, or the prevention of neck-in occurrence. More specifically, from a practical point of view, the extrusion amount of one shot in intermittent extrusion is preferably 1 to 10 kg, and the extrusion rate of the resin from the extrusion slit 34 is several hundred kg / hour or more, more preferably 700 kg / hour or more. Further, from the viewpoint of preventing the draw-down of the thermoplastic resin sheet P or the occurrence of neck-in, the extrusion process of the thermoplastic resin sheet P is preferably as short as possible, depending on the type of resin, MFR value, and melt tension value. In general, the extrusion process should be completed within 40 seconds, more preferably within 10 to 20 seconds. For this reason, the unit area and the amount of extrusion per unit time from the extrusion slit 34 of the thermoplastic resin are 50 kg / hour cm ² or more, more preferably 150 kg / hour cm ² or more.

By feeding the thermoplastic resin sheet P sandwiched between the pair of rollers 30 by the rotation of the pair of rollers 30 downward, the thermoplastic resin sheet P can be stretched and thinned, and extruded thermoplastic. By adjusting the relationship between the extrusion speed of the resin sheet P and the feed speed of the thermoplastic resin sheet P by the pair of rollers 30, it is possible to prevent the occurrence of drawdown or neck-in. It is possible to reduce the restrictions on the type, in particular the MFR value and the melt tension value, or the extrusion rate per unit time.

As shown in FIG. 2, the extrusion slit 34 provided in the T-die 28 is arranged vertically downward, and the thermoplastic resin sheet P extruded from the extrusion slit 34 is vertically suspended from the extrusion slit 34 in the vertical direction. It is sent downwards. The extrusion slit 34 can change the thickness of the thermoplastic resin sheet P by making the interval variable.

The pair of rollers 30 will be described. In the pair of rollers 30, the rotation axes of the pair of rollers 30 are arranged substantially horizontally in parallel with each other, one is the rotation drive roller 30A, and the other is driven to rotate. The roller 30B. More specifically, as shown in FIG. 2, the pair of rollers 30 are arranged so as to be line-symmetric with respect to the thermoplastic resin sheet P extruded in a form that hangs downward from the extrusion slit 34.

The diameter of each roller and the axial length of the roller may be appropriately set according to the extrusion speed of the thermoplastic resin sheet P to be molded, the length and width of the sheet in the extrusion direction, the type of resin, and the like. As will be described later, from the viewpoint of smoothly feeding the thermoplastic resin sheet P downward by rotation of the roller with the thermoplastic resin sheet P sandwiched between the pair of rollers 30, the diameter of the rotational drive roller 30A Is preferably slightly larger than the diameter of the driven roller 30B. The diameter of the roller is preferably in the range of 50 to 300 mm, and the thermoplastic resin sheet P wraps around the roller even when the roller curvature is too large or too small in contact with the thermoplastic resin sheet P. It causes a malfunction.
On the other hand, the mold clamping device 14 is also a conventionally known type like the extrusion device 12, and detailed description thereof will be omitted, but the two divided molds 32A and 32B and the molds 32A and 32B are melted. And a mold driving device that moves between an open position and a closed position in a direction substantially perpendicular to the supply direction of the thermoplastic resin sheet P.

As shown in FIG. 2, the two divided molds 32A and 32B are arranged with the cavities 116 facing each other, and the cavities 116 are arranged along the substantially vertical direction. The surface of each cavity 116 is provided with irregularities according to the outer shape and the surface shape of the molded product molded based on the molten thermoplastic resin sheet P.

One mold 32A is provided with a plate-like slide core 300 (300A to 300D) having a predetermined thickness, and slide core driving means (not shown) for reciprocating each slide core 300, Each slide core 300 is installed in a space provided in the mold 32A, and is configured to be slidable with respect to the inner surface of the mold 32A.
The thickness D of the slide core 300 is determined from the viewpoint of the thickness required for the inner rib 122 formed by the slide core 300 and the welding area required for welding the inner rib 122.
The slide core driving means may be a cam, a gear mechanism, a hydraulic pressure or an air cylinder.
The surface of the slide core 300 may be formed of a fluororesin that is slippery with respect to the parison, and the surface of the slide core 300 is roughened in order to form the coating layer firmly on the surface of the slide core 300. It is good to make a face.
A plurality of (four in the figure) slide cores 300 are provided at predetermined intervals in the vertical direction in accordance with the bending rigidity required for the finished resin laminate 10. Is provided so as to extend horizontally across the cavity of the mold 32A.

In each of the two divided molds 32A and 32B, a pinch-off part 118 is formed around the cavity 116. The pinch-off part 118 is formed in an annular shape around the cavity 116, and the opposing molds 32A and 32B are formed. Protrusively toward. As a result, when the two divided molds 32A and 32B are clamped, the tip portions of the respective pinch-off portions 118 come into contact with each other, and the two molten thermoplastic resin sheets P1 and P2 are formed on the periphery thereof. It is welded so that the parting line PL is formed, and an outer peripheral wall that closes the hollow portion is formed.

A mold 33A is slidably fitted on the outer periphery of the mold 32A so as to be slidable in a sealed state, and the mold 33A can be moved relative to the mold 32A by a mold moving device (not shown). . More specifically, the mold frame 33A can be brought into contact with the side surface of the thermoplastic resin sheet P1 disposed between the molds 32A and 32B by projecting toward the mold 32B with respect to the mold 32A. is there.

The mold driving device is the same as the conventional one, and the description thereof is omitted. However, the two divided molds 32A and 32B are respectively driven by the mold driving device and are divided into two in the open position. Two molten thermoplastic resin sheets P can be disposed between the molds 32A and 32B, and the pinch-off portions 118 of the two divided molds 32A and B are in contact with each other at the closed position. The annular pinch-off portions 118 are in contact with each other so that a sealed space is formed in the two divided molds 32A and 32B. Regarding the movement of the molds 32A, 32B from the open position to the closed position, the closed position, that is, the position where the pinch-off portions 118 are in contact with each other is between two molten thermoplastic resin sheets P1, P2. The two molds 32A and 32B are driven by a mold driving device so as to move toward the positions at equal positions from both the thermoplastic resin sheets P1 and P2.
The extrusion device and the pair of rollers for one thermoplastic resin sheet P1 and the extrusion device and the pair of rollers for the other thermoplastic resin sheet P2 are arranged symmetrically with respect to this closed position. Yes.

A vacuum suction chamber (not shown) is provided inside the divided mold 32A, and the vacuum suction chamber communicates with the cavity 116A through a suction hole (not shown), and from the vacuum suction chamber through the suction hole. By sucking, the thermoplastic resin sheet P1 is adsorbed toward the cavity 116A and shaped into a shape along the outer surface of the cavity 116A. More specifically, the vacuum suction chamber and the suction hole extending therefrom toward the outer surface of the cavity 116A may be provided so as not to interfere with the slide cores 300A to 300D inside the divided mold 32A.
On the other hand, a conventionally known blow pin (not shown) is applied to the divided mold 32B so that when the molds 32A and 32B are clamped, blowing pressure can be applied from within the sealed space formed by both molds. ) Is installed.

The thermoplastic resin sheets P1 and P2 which are materials of the front side sheet 120A and the back side sheet 120B are made of an olefin resin such as polyethylene or polypropylene, or an amorphous resin. More specifically, for the thermoplastic resin sheets P1 and P2, it is preferable to use a resin material having a high melt tension from the viewpoint of preventing the occurrence of variations in thickness due to drawdown, neck-in, etc. It is preferable to use a resin material with high fluidity in order to improve transferability to the mold and followability.

More specifically, it is a polyolefin (for example, polypropylene, high density polyethylene) which is a homopolymer or copolymer of an olefin such as ethylene, propylene, butene, isoprene pentene, methyl pentene, etc., and has an MFR (JIS) at 230 ° C. According to K-7210, measured at a test temperature of 230 ° C. and a test load of 2.16 kg) of 3.0 g / 10 min or less, more preferably 0.3 to 1.5 g / 10 min, or acrylonitrile butadiene Amorphous resin such as styrene copolymer, polystyrene, high impact polystyrene (HIPS resin), acrylonitrile / styrene copolymer (AS resin), MFR at 200 ° C. (test temperature 200 according to JIS K-7210) ℃, measured at a test load of 2.16 kg) is 3.0 to 60 g / 10 min More preferably, the melt tension at 30 to 50 g / 10 min and at 230 ° C. (using a melt tension tester manufactured by Toyo Seiki Seisakusho Co., Ltd., preheating temperature 230 ° C., extrusion speed 5.7 mm / min, diameter 2.095 mm, long A strand is extruded from an orifice having a length of 8 mm, and a tension when the strand is wound around a roller having a diameter of 50 mm at a winding speed of 100 rpm is 50 mN or more, preferably 120 mN or more.

Further, in order to prevent the thermoplastic resin sheets P1 and P2 from being cracked by impact, it is preferable that a hydrogenated styrene thermoplastic elastomer is added in an amount of less than 30 wt%, preferably less than 15 wt%. . Specifically, a styrene-ethylene / butylene-styrene block copolymer, a styrene-ethylene / propylene-styrene block copolymer, a hydrogenated styrene-butadiene rubber and a mixture thereof are suitable as the hydrogenated styrene-based thermoplastic elastomer. The styrene content is less than 30 wt%, preferably less than 20 wt%, and the MFR at 230 ° C. (measured at a test temperature of 230 ° C. and a test load of 2.16 kg according to JIS K-7210) is 1.0 to 10 g / 10. Minute, preferably 5.0 g / 10 min or less and 1.0 g / 10 min or more.
Furthermore, the thermoplastic resin sheets P1 and P2 may contain an additive. Examples of the additive include inorganic fillers such as silica, mica, talc, calcium carbonate, glass fiber, and carbon fiber, and plasticizer. , Stabilizers, colorants, antistatic agents, flame retardants, foaming agents and the like.
Specifically, silica, mica, glass fiber or the like is added in an amount of 50 wt% or less, preferably 30 to 40 wt%, based on the molding resin.

In the case where the decorative material sheet 140 is provided on the surface of the thermoplastic resin sheet P2 that is the material of the front surface sheet 120A, the decorative material sheet 140 is an object that improves appearance, decoration, and contacts with the molded product ( For example, in the case of a cargo floor board, the cargo floor board is configured for the purpose of protecting a load placed on the upper surface of the board. The material of the decorative material sheet 140 is a fiber skin material, a sheet-like skin material, a film-like skin material, or the like. As the material of such a fiber skin material, synthetic fibers such as polyester, polypropylene, polyamide, polyurethane, acrylic and vinylon, semi-synthetic fibers such as acetate and rayon, regenerated fibers such as viscose rayon and copper ammonia rayon, cotton, hemp, Examples thereof include natural fibers such as wool and silk, or blended fibers thereof.

Among these, polypropylene or polyester is preferable and polyester is more preferable from the viewpoints of touch, durability, and moldability. The yarn used for the fiber skin material is, for example, polyester: (3-5) denier × (50-100) mm or other fineness of 3-15 denier, and a staple spun yarn having a fiber length of about 2-5 inches Polyester in a bundle of thin flexible filaments: about 150 to 1000 denier / 30 to 200 filaments = about 5 denier × 30 to 200 multifilaments, or polyester: 400 to 800 deniers per filament -It is preferable to use in combination with a filament.

Examples of the structure of the decorative material sheet 140 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, since there is no directionality with respect to elongation, a non-woven fabric is preferable because it can be easily formed into a three-dimensional shape and has excellent surface feel and texture. Here, the non-woven fabric means a cloth-like product in which fibers are stacked in parallel or alternately or are randomly dispersed to form a web, and then the fibers that become the web are joined. Among these, it is preferable that it is a nonwoven fabric manufactured by the needle punch method from a viewpoint of the three-dimensional shape reproducibility of a molded article, and an external appearance characteristic. In addition, since the nonwoven fabric obtained by the needle punch method has lower strength and higher elongation than the woven fabric and has a large degree of deformation in any direction, it improves the strength of the nonwoven fabric and stabilizes its dimensions. For this reason, it is more preferable to attach a binder to the woven fabric or to punch the web and the nonwoven fabric with overlapping needles. From these things, it is more preferable that the decorative material sheet 140 is a polypropylene nonwoven fabric or a polyester nonwoven fabric. In this case, since the decorative material sheet 140 itself is thermoplastic, it can be used for another purpose by being heated and deformed after separation and collection. For example, if the main resin layer is made of polypropylene and the decorative material sheet 140 is made of a polypropylene nonwoven fabric, the main resin layer and the decorative material sheet 140 of the molded product are the same material, which facilitates recycling.

On the other hand, if the decorative material sheet 140 is a polyester non-woven fabric, the melting point of the main resin layer composed of polypropylene and the fiber skin material are different, so that when the decorative material sheet 140 is bonded to a molded product, it is altered or deformed by heat. Or problems such as failure to adhere to the correct position can be suppressed. In this case, the moldability, rigidity, appearance and durability are also excellent. The tensile strength of the decorative material sheet 140 is 15 kg / cm from the viewpoint of three-dimensional shape reproducibility and moldability.
It is preferably ² or more, and the elongation is preferably 30% or more. In addition, the value of this tensile strength and elongation is measured based on JIS-K-7113 at the temperature of 20 degreeC. As the sheet-like skin material and film-like skin material, thermoplastic elastomer, embossed resin layer, resin layer with printed layer attached to the outer surface, synthetic leather, non-slip mesh-shaped skin layer, etc. can be used. .
A method for manufacturing the laminated plate 100 using the molding apparatus 10 for the laminated plate 100 having the above configuration will be described below with reference to the drawings.

  First, in FIG. 2, a predetermined amount of the melted and kneaded thermoplastic resin is stored in the accumulator 22, and the stored thermoplastic resin is discharged from the extrusion slit 34 provided at a predetermined interval on the T die 28 at a predetermined extrusion amount per unit time. In this case, the thermoplastic resin swells and is extruded at a predetermined extrusion speed with a predetermined thickness so as to hang downward into a molten sheet.

Subsequently, the pair of rollers 30 is moved to the open position, and the gap between the pair of rollers 30 arranged below the extrusion slit 34 is expanded from the thickness of the thermoplastic resin sheet P, thereby being extruded in a molten state. The lowermost part of the thermoplastic resin sheet P is smoothly supplied between the pair of rollers 30. In addition, the timing which expands the space | interval of the rollers 30 from the thickness of the sheet | seat P made from a thermoplastic resin may be performed at the time of the completion | finish of secondary shaping | molding for every one shot not after an extrusion start.
Next, the pair of rollers 30 are moved close to each other and moved to the closed position, the interval between the pair of rollers 30 is narrowed to sandwich the thermoplastic resin sheet P, and the thermoplastic resin sheet P is moved downward by the rotation of the rollers. Send it out.
Next, as shown in FIG. 2, the thermoplastic resin sheet P having a uniform thickness in the extrusion direction is disposed between the split molds 32 </ b> A and 32 </ b> B disposed below the pair of rollers 30. Thereby, the thermoplastic resin sheet P is positioned in a form that protrudes around the pinch-off portion 118.
The above process is performed for each of the two thermoplastic resin sheets P1 and P2, and the thermoplastic resin sheet P2 that is the material of the front side sheet 120A and the thermoplastic resin that is the material of the back side sheet 120B. The manufactured sheet P1 is disposed between the divided molds 32A and 32B in a state of being spaced apart from each other.
In this case, the two thermoplastic resin sheets P1 and P2 are arranged between the divided molds 32A and 32B by adjusting the distance between the extrusion slits 34 or the rotational speed of the pair of rollers 30 independently of each other. It is possible to adjust the thickness when being applied.

More specifically, the thickness of the thermoplastic resin sheet P1 is such that the thickness of the inner rib 122 is required from the viewpoint of reducing the thickness of the back surface sheet 120B by the inner rib 122 to be formed later and the required rigidity. In consideration of the above, the thickness required for the back side sheet 120B may be determined and determined accordingly, while the thickness of the thermoplastic resin sheet P2 is on the front side sheet 120A side, Since the inner rib 122 is not formed, it is possible to set the thickness to be thinner than the thickness of the thermoplastic resin sheet P1 without considering the thinning caused by the inner rib 122, thereby ensuring the rigidity while reducing the weight. It is possible to do.
Next, as shown in FIG. 3, the mold 33 </ b> A faces the mold 32 </ b> A toward the thermoplastic resin sheet P <b> 1 that is the material of the back surface sheet 120 </ b> B, and the thermoplastic resin sheet P <b> 1 that faces the mold 32 </ b> A. Until it touches the outer surface 117.
The decorative material sheet 14 may be appropriately suspended above the mold and suspended in advance along the cavity surface. The timing of disposing the decorative material sheet 14 may be performed before the pair of molds 32A and 32B are clamped.

Next, from the vacuum suction chamber through the first sealed space 84 formed by the cavity 116A of the mold 32A, the inner peripheral surface 102 of the mold 33A, and the outer surface 117 of the thermoplastic resin sheet P1 facing the mold 32A. The outer surface of the thermoplastic resin sheet P1 is pressed against the cavity 116A of the mold 32A by projecting each of the plurality of slide cores 300A to 300D toward the mold 32B while sucking through the suction holes. As a result, the thermoplastic resin sheet P1 is shaped, and a part of the thermoplastic resin sheet P1 is projected in a U-shaped cross section toward the mold 32B. At that time, the thermoplastic resin sheet P1 in the vicinity of a part of the protruding thermoplastic resin sheet P1 is thinned. However, as described above, the thermoplastic resin sheet P2 in consideration of this point. The thickness of the thermoplastic resin sheet P1 may be adjusted in advance separately from the above.

Next, a part of the tip 301 of the thermoplastic resin sheet P1 protruding in a U-shaped cross section is butt-welded to the inner surface 302 of the thermoplastic resin sheet P2. Thereby, a part of the thermoplastic resin sheet P1 is integrated with the thermoplastic resin sheet P2, and each slide core 300 located between the U-shaped cross sections can be retracted toward the mold 32A. Become.

In this case, the decorative material sheet 14 can be welded to the thermoplastic resin sheet P <b> 2 by the butt pressure by the slide core 300. Furthermore, by adjusting the butt pressure so as not to leave a pressing mark on the surface of the decorative material sheet 14, when the decorative material sheet 14 is, for example, a non-woven fabric having fluff, it is possible to prevent hair fall. is there. In addition, when the butting pressure is insufficient, the decorative material sheet 14 may be permanently welded to the thermoplastic resin sheet P2 by applying a blow pressure after the mold clamping of the mold, which is a subsequent process.

Next, as shown in FIG. 4, while holding the thermoplastic resin sheet P <b> 1 in a state where the mold 33 </ b> A that contacts the outer surface 117 of the thermoplastic resin sheet P <b> 1 is held as it is, The molds 32A and 32B are moved in a direction approaching each other until the pinch-off portions 118A and B come into contact with each other, and the molds are clamped. In this case, the contact position in the mold clamping direction between the pinch-off portions 118A and 118B is between the two thermoplastic resin sheets P1 and P2 that are spaced apart from each other. As shown in FIG. When B contacts each other, the two thermoplastic resin sheets P1 and P2 are welded and fixed to each other, and a parting line is formed. Thereby, the sealed hollow portion 280 is formed between the back surface side sheet 120B and the front surface side sheet 120A.

Next, as shown in FIG. 5, by retracting the slide cores 300 </ b> A to 300 </ b> D toward the mold 32 </ b> A, a part of the inner surfaces 304 of the thermoplastic resin sheet P <b> 1 protruding in a U-shaped cross section are mutually connected. Make them face each other. At that time, a part of the front end of the thermoplastic resin sheet P1 is welded to the inner surface 302 of the thermoplastic resin sheet P2. Therefore, even if the slide core 300 is retracted, a part of the thermoplastic resin sheet P1 is retracted. Will not follow it.

Next, by applying a blow pressure from the sealed hollow portion 280 in the mold clamped through the blow pin, the inner surfaces 304 facing each other are welded to form the inner rib 122. At that time, the opening of the outer surface 117 of the back-side sheet 120B formed by pulling out the slide core 300 is completely closed, and only linear traces remain on the outer surface 117 of the back-side sheet 120B.
Next, as shown in FIG. 6, the split molds 32A and B are opened, the molded laminate 100 is taken out, the burr portions B outside the pinch-off portions 118A and B are cut, and the molding is completed with this. To do.

As described above, each time the molten thermoplastic resin sheet P is intermittently extruded, the sheet-like laminate 100 can be formed one after another by repeating the above steps. The thermoplastic resin is intermittently extruded as a thermoplastic resin sheet P in a molten state by molding, and the thermoplastic resin sheet P extruded by vacuum forming or pressure forming is shaped into a predetermined shape using a mold. Is possible.

  According to the manufacturing method of the resin laminated board provided with the inner rib 122 having the above-described configuration, a concave portion is provided on the outer surface of one thermoplastic resin sheet, thereby providing no rib, but one mold 32A. The inner rib 122 is formed by using the slide core 300 provided on the inner surface of the thermoplastic resin sheet, and the inner rib 122 is particularly formed while maintaining the aesthetic appearance without providing an opening on the outer surface of the one thermoplastic resin sheet. It is possible to ensure bending rigidity by providing a plurality and narrowing the interval between adjacent inner ribs 122, and at the same time, by clamping a pair of molds 32, two molten thermoplastic resins are made. By welding the peripheral edges of the sheet, a separate end face treatment as in the prior art becomes unnecessary, and the manufacturing efficiency can be improved.

  At that time, according to the conventional blow molding, a cylindrical parison is used to form the shape along the cavity by blowing pressure, and therefore the slide core 300 is provided only in the cavity of one mold 32A. While the parison is greatly stretched on the cavity side having the slide core 300, on the other hand, the cavity side without the slide core 300 is relatively stretched without causing the parison to be stretched. After positioning the two thermoplastic resin sheets whose thicknesses are adjusted between the divided molds 32, a sealed space is formed between one resin sheet and the cavity of the mold 32A facing the resin sheet. In order to solve this problem and secure the required strength, the inside of the sealed space is sucked from the mold side. It is possible to reduce the thickness of each of the two thermoplastic resin sheets to the maximum individually, thereby achieving sufficient weight reduction and thinning while ensuring manufacturing efficiency and product quality. It is.

Although the embodiments of the present invention have been described in detail above, various modifications or changes can be made by those skilled in the art without departing from the scope of the present invention. For example, in the present embodiment, it has been described that the inner rib forming step is performed by applying a blow pressure from the inside of the sealed portion after the slide core is retracted toward one mold, but is limited to this. Alternatively, it may be performed by applying a blow pressure from the inside of the sealed portion while retracting the slide core toward one mold.

Moreover, in this embodiment, although demonstrated as what shape | molds and shape | molds directly as the laminated board 100 using the extruded thermoplastic resin sheet, it is not limited to it, but shaping As long as the molten state necessary for molding is realized, shaping and molding may be performed using a material that has been once extruded and then heated again to a molten thermoplastic resin sheet.

Further, in the present embodiment, when the front side sheet 120A is disposed between the pair of molds, the decorative material sheet 140 is held above the mold and is suspended along the cavity surface. However, the present invention is not limited thereto, and the mold may be clamped in a state where the decorative material sheet 140 is disposed in the cavity 116B by sucking the decorative material sheet 140 from the mold 32B, for example, It is good also as what is arrange | positioned in the state which the decorative material sheet 140 adhere | attached previously.

It is a perspective view of the resin laminated board which concerns on embodiment of this invention. It is a side view which shows the state by which the molten resin sheet was arrange | positioned between the division molds with the shaping | molding apparatus which concerns on embodiment of this invention. In the molding apparatus which concerns on embodiment of this invention, while making the outer frame of a division mold contact the side surface of a molten resin sheet, it is a schematic partial side view which shows the condition which has protruded the slide core. It is a figure which shows the state which clamped the division mold in the shaping | molding apparatus which concerns on embodiment of this invention. In the shaping | molding apparatus which concerns on embodiment of this invention, it is a general | schematic fragmentary sectional view which shows the condition which has pulled out the slide core. In the molding apparatus which concerns on embodiment of this invention, it is a figure which shows the state which opened the split mold.

P Thermoplastic resin sheet PL Parting line 10 Molding device 12 Extruding device 14 Clamping device 16 Hopper 18 Cylinder 20 Hydraulic motor 22 Accumulator 24 Plunger 28 T die 30 Roller 32 Dividing mold 33 Mold frame 34 Extrusion slit 80 Vacuum suction Chamber 82 Vacuum suction hole 84 First sealed space 86 Second sealed space 100 Laminated plate
102 Inner peripheral surface 116 Cavity 117 Outer surface 118 Pinch-off portion 119 Projection body 120 Sheet 122 Inner rib 140 Cosmetic material sheet 150 Outer surface of front surface side sheet 170 Inner surface of front surface side sheet 180 Inside of rear surface side sheet Surface 200 Concave portion 220 Outer surface 240 of back side sheet Abutting surface 260 Opening 280 Sealed hollow portion 300 Slide core 302 Inner surface 304 Opposing inner surface

Claims (8)

A pair of split molds in which a slide core that can be moved back and forth with respect to the other mold is provided in the cavity of one mold, and two melted thermoplastics whose thicknesses are adjusted independently of each other A pair of split-type sheets is prepared in such a manner that a resin sheet is prepared and two molten thermoplastic resin sheets are spaced from each other by a predetermined distance and protrude around an annular pinch-off portion provided in each mold. Positioning between molds, forming a sealed space between one thermoplastic sheet opposite to one mold cavity and one mold cavity, and one mold those pushing the steps of vacuum suction to the closed space from the cavity side, one of the thermoplastic outer surface of the resin sheet against the other mold one mold cavity is projected to slide core toward the The Rukoto the steps of shaping a state projecting in a U-shape toward the part of one of the thermoplastic resin sheet on the other mold, after which one part of the tip of the thermoplastic resin sheet Butt-welded to the inner surface of the other thermoplastic resin sheet, and during or after butt welding of one thermoplastic resin sheet to the other thermoplastic resin sheet, Welding the peripheral edges of the thermoplastic resin sheet to form a hermetic seal inside the two molten thermoplastic resin sheets; after clamping the pair of molds, By retracting toward the mold, the step of making one inner surface of one of the thermoplastic resin sheets protruding in a U-shape face each other, and applying a blow pressure from within the sealed portion, By welding opposite inner faces, and forming the inner ribs, characterized in that it has, method for producing a resin laminate having an inner rib.         The method for producing a resin laminate having an inner rib according to claim 1, wherein the forming step of the inner rib includes a step of applying a blow pressure from the inside of the sealed portion while retracting the slide core toward one mold. . The positioning step of the two thermoplastic resin sheets has a step of disposing a decorative material between the cavity of the other mold and the other thermoplastic resin sheet,
The butt welding step of the one thermoplastic resin sheet includes a step of welding the decorative material to the other thermoplastic resin sheet with a butt pressure that does not leave a pressing mark on the surface of the decorative material. The manufacturing method of the resin laminated board provided with the inner rib of claim | item 1. Furthermore, the formation process of the said inner rib has a step which welds a decorative material with respect to the sheet | seat made from another thermoplastic resin, The manufacturing method of the resin laminated board provided with the inner rib of Claim 2. 2. The resin laminated board having an inner rib according to claim 1, wherein the resin laminated board has inner ribs according to claim 1, wherein the resin laminated board has a step of extruding between a pair of divided molds in a form in which a melted sheet-like parison is suspended downward. Production method. A plurality of the slide cores are provided at predetermined intervals in the vertical direction according to the bending rigidity required for the resin laminate, and each slide core is provided in the horizontal direction across the cavity of one mold. The manufacturing method of the resin laminated board provided with the inner rib of Claim 4. The suction step includes a step of moving an outer frame that is externally fitted to a peripheral edge of the one mold so as to be movable in a mold clamping direction toward the outer surface of the one thermoplastic resin sheet. The manufacturing method of the resin laminated board provided with the inner rib of Claim 1 which comprises sealed space with the outer surface of a sheet | seat made from a thermoplastic resin, the internal peripheral surface of the said outer frame, and the cavity of said one metal mold | die. Through clamping the pair of molds, the respective pinch-off portions are brought into contact with each other to weld the peripheral edges of two molten thermoplastic resin sheets to form a parting line. The manufacturing method of the resin laminated board provided with the inner rib of Claim 1 which forms a sealed hollow part between the sheets made from a thermoplastic resin of a molten state.

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