JP2018065383A - Method for production of laminate molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for production of a laminate molding in which a planar skirt portion of a preform molded body is sandwiched between mating surfaces of a female mold and a male mold and fixed to perform in-mold molding, wherein the generation of wrinkles in the laminated preform molded bodies is suppressed.SOLUTION: The method for production of a laminate molding includes the steps of: preparing a preform molded body having a main body portion shaped into a three-dimensional shape and a skirt portion continuous to the periphery of the main body portion; disposing the preform molded body so that the main body portion is accommodated in the cavity portion; clamping the skirt so as to sandwich it at the mating surface; and charging a molten resin into the cavity from a gate. In the preform molded body, the length L (A) from the point G1 facing the center of the gate to the point A corresponding to the farthest point reached by the molten resin charged from the gate is formed to be shorter than the length L (B) from the point G2 facing the center of the gate to the point B corresponding to the farthest point reached by the molten resin charged from the gate, on the surface of the female mold.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing a laminated molded body by in-mold molding using a preform molded body obtained by molding a sheet material.

  In-mold molding is known in which a preform molded body obtained by molding a sheet material having design properties is placed in a cavity of a mold and injection molding is performed. According to in-mold molding, a laminated molded body in which a sheet material having design properties is integrated on the surface of an injection molded body can be manufactured. As a sheet material having design properties, a film protected by a glossy layer or a hard coat layer and provided with a pattern by painting, transfer, gravure printing or the like is widely used.

  A general method for producing a laminated molded body by in-mold molding using a preform molded body will be described with reference to FIG. In FIG. 11, 11 is a preform molded body, 2a is a female mold, 2b is a male mold, 3 is an injection body of an injection molding machine, 3a is a nozzle, 3b is a cylinder, 3c is an in-line screw, 4 is a gate, 5 is An injection molded body, 5a is a molten resin, and 20 is a laminated molded body.

  In in-mold molding using a preform molded body, first, as shown in FIG. 11 (a), an injection mold having a female mold 2a having a cavity 2c and a male mold 2b having a core 2d. 2, the preform molded body 11 is disposed in the cavity portion 2 c of the female mold 2 a. Then, as shown in FIG. 11B, the female mold 2a and the male mold 2b are clamped. And as shown in FIG.11 (c), the cavity c formed by clamping the female type | mold 2a and the male type | mold 2b is filled with the molten resin 5a of a thermoplastic resin.

  And after completion | finish of the cooling process which cools the molten resin 5a in the cavity c, as shown in FIG.11 (d), the female type | mold 2a is retracted, and the female type | mold 2a and the male type | mold 2b are mold-opened. Thus, a laminated molded body 20 in which the preform molded body 11 is integrated with the injection molded body 5 is obtained.

  In in-mold molding of a film having design properties, the molten resin is injected at a temperature higher than the deflection temperature under load of the film, so that the film is softened and stretched by the heat and flow of the molten resin, and an injection molded body It has been known that wrinkles occur in the film integrated with the film. As a method for suppressing the occurrence of such wrinkles, for example, the following Patent Document 1 is molded so as to be curved without contacting a mold at a portion corresponding to a corner of a molded product in a closed state, By using a preform molded body whose end surface is punched so as to contact the mold at a position corresponding to the edge of the inner surface of the rising portion of the molded product, wrinkles are generated in the film integrated with the injection molded body. It is disclosed that this is suppressed.

  By the way, in recent years, as a sheet material for in-mold molding which gives a soft touch in addition to design properties, a laminated molded body using a fiber structure (textile) thicker than a film has been proposed (for example, the following patent document) 2).

JP 2005-104114 A JP-A-6-328498

  By forming a three-dimensional shape on the sheet material using a sheet forming method such as hot press forming, vacuum forming, vacuum pressure forming, etc., A preform molded body having a flat hem that continues to the periphery is manufactured. Since the hem that is connected to the periphery of the main body is usually an unnecessary part, the hem can be removed by punching or the like, and a preform molded body having only the main body can be accommodated in the cavity and in-mold molding can be performed. Many.

  However, the preform molded body accommodated in the cavity of the mold by this method has a problem that it is displaced in the cavity. In order to avoid such misalignment, a method is used in which the preform is attached to the cavity of the mold with double-sided tape, vacuum-adsorbed, or fitted into the protrusion of the core, and fixed. ing.

  As a method for fixing the preform molded body to the cavity portion of the mold, the present inventors formed a body portion 1a formed three-dimensionally and a periphery of the body portion 1a as shown in FIG. By using the preform molded body having the flat hem 1b as it is, the main body 1a is accommodated in the cavity, and the flat hem 1b is sandwiched and fixed between the mating surfaces of the female mold and the male mold. It was studied to suppress the displacement of the preform molding in the interior.

  However, when injection molding is performed with the flat hem sandwiched between the mating surfaces of the female and male molds, it is integrated with the laminated molded product near the end of the region where the flow length of the molten resin increases. There was a tendency that wrinkles were likely to occur in the preform formed article.

  The present invention relates to a laminated preform in a method for producing a laminated molded body in which a flat hem portion of such a preform molded body is sandwiched and fixed between a mating surface of a female mold and a male mold and in-mold molding is performed. It aims at suppressing the generation | occurrence | production of the wrinkle of a molded object.

  The present inventors use a preform molded body that leaves a skirt around the main body part, accommodates the main body part in a cavity, fixes the hem part between the mating surfaces of the female mold and the male mold, and fixes the inner part. In the manufacturing method of the laminated molded body which performs mold forming, the cause that wrinkles are likely to occur near the end of the region where the flow length of the molten resin becomes long was examined. And I thought that wrinkles occurred by the following mechanism.

  FIG. 6 is an explanatory diagram for explaining the mechanism of wrinkles generated in the laminated molded body, and shows how the molten resin 5a is filled into the injection mold 2 in order from (a) to (c). It shows. In in-mold molding, as shown in FIG. 6 (a), the skirt 1b formed around the main body 1a of the preform molded body 1 is sandwiched between the mating surfaces of the female mold 2a and the male mold 2b. Is fixed. The preform molded body 1 accommodated in the cavity of the injection mold 2 is indicated by an arrow while receiving heat from the molten resin 5a filled through the gate 4 from the nozzle 3a of the injection molding machine. It receives shearing force in the flow direction. For this purpose, the preform 1 is stretched in the flow direction of the molten resin 5a.

  When the skirt 1b formed around the main body 1a of the preform 1 is sandwiched between the mating surfaces of the female mold 2a and the male mold 2b, as shown in FIG. In the vicinity of the end E where the flow length of 5a becomes long, the stretched part of the preform 1 starts to sag. And as shown in FIG.6 (c), the stretched and slack part of the preform molded object 1 buckles at the time of complete filling, and generates wrinkles. Based on such findings, the present inventors designed the preform molded body in such a shape that the portion extending near the end of the region where the flow length becomes long does not sag, thereby generating wrinkles. The present inventors have found that a laminated molded article that is suppressed can be obtained, and have arrived at the present invention.

  That is, one aspect of the present invention includes a step of preparing a preform molded body having a main body portion shaped into a three-dimensional shape and a skirt portion continuous to the periphery of the main body portion, a male mold having a core portion, and a mold clamping And a step of placing a preform molded body so that the body portion is accommodated in the cavity portion, and a body portion in the cavity portion. In a state in which the hem is sandwiched between the mating surfaces, the step of clamping the female mold and the male mold, and by filling the cavity with the molten resin from at least one gate formed in the male mold, And a step of integrating the injection molded body to be molded and the preform molded body, the preform molded body from the point G1 facing the center of the gate on the surface facing the female mold from the main body portion And the hem On the line, the length L (A) to the point A corresponding to the farthest point where the molten resin filled from the gate reaches from the point G2 facing the center of the gate on the surface of the female mold, Lamination formed to be 0.5 to 15% shorter than the length L (B) from the gate to the point B corresponding to the farthest point where the molten resin to be filled arrives on the boundary line with the mating surface It is a manufacturing method of a molded object.

  According to the present invention, a preform molded body having a main body portion shaped into a three-dimensional shape and a skirt portion around the main body portion is used, the main body portion is accommodated in the cavity portion, and the skirt portion is a female mold and a male mold. When the in-mold molding is performed by being sandwiched between the mating surfaces, a laminated molded body in which generation of wrinkles is suppressed is obtained.

Drawing 1 is an explanatory view explaining each process of a manufacturing method of a lamination fabrication object of an embodiment. 2A and 2B are perspective schematic views of the preform molded body 1 used in the embodiment, where FIG. 2A is a top view and FIG. 2B is a bottom view. FIG. 3 is a schematic perspective view of the cavity forming surface of the female mold 2a and the male mold 2b of the injection mold used in the embodiment. FIG. 4 is a schematic perspective view for explaining the positional relationship when the preform molded body 1 is aligned with the cavity 2c of the female mold 2a of the injection mold. FIG. 5 is an explanatory view schematically showing a state in which the molten resin 5a is filled in the cavity c of the injection mold 2 in which the preform molded body 1 is accommodated. FIG. 6 is an explanatory diagram for explaining a mechanism in which wrinkles occur in the laminated molded body. FIG. 7 is a schematic perspective view for explaining the positional relationship when the preform molded body is aligned with the cavity portion of the injection mold 12 having a fan gate. FIG. 8 is a schematic perspective view for explaining the positional relationship when the preform molded body is aligned with the cavity portion of the injection molding die 22 having two pin gates. FIG. 9 is a schematic perspective view of the preform molded body manufactured in Example 1, where (a) is a top view and (b) is a bottom view. 10A is a diagram illustrating the shape of the preform molded body manufactured in Example 2, and FIG. 10B is an explanatory diagram illustrating the shape of the in-mold molded body manufactured in Example 2. FIG. FIG. 11 is an explanatory view for explaining each step of a method for producing a laminated molded body by in-mold molding using a conventional preform molded body.

  The manufacturing method of the laminated molded body of this embodiment is demonstrated with reference to drawings. FIG. 1 is an explanatory view for explaining each step of the method for producing a laminated molded body of the present embodiment.

  In FIG. 1, 1 is a preform molded body having a body portion 1a shaped in a three-dimensional shape and a skirt portion 1b connected to the periphery thereof, 2a is a female die having a concave cavity portion 2c, and 2b is a core portion 2d. 3 is an injection part body of an injection molding machine, 3a is a nozzle, 3b is a cylinder, 3c is an in-line screw, 4 is a gate, 5 is an injection molding, 5a is a molten resin, 9 is an in-mold molding ( Laminated molded body). Reference numeral 10 denotes a final product obtained by cutting the skirt 1b of the preform molded body 1 and the sprue runner 9b of the injection molded body 5a from the in-mold molded body 9. The female mold 2a and the male mold 2b are paired to form an injection mold 2 that forms a cavity c. In the present embodiment, the female mold 2a is the movable side of the injection mold, and the male mold 2b is the fixed side of the injection mold.

  FIG. 2 is a schematic perspective view of the preform 1, (a) when viewed from the top, and (b) when viewed from the bottom. The preform molded body 1 includes a main body portion 1a formed into a three-dimensional shape that forms a product main body portion, and a flat skirt portion 1b that is trimmed and removed later.

  In the method for producing a laminated molded body of the present embodiment, first, as shown in FIG. 1A, the preform molded body 1 is accommodated in the concave cavity portion 2c of the female mold 2a. In order not to shift the position of the preform molded body, it is affixed to the surface of the cavity portion with double-sided tape, vacuum-adsorbed, attached using the surface adhesiveness of the preform molded body itself, or provided with protrusions on the cavity portion. In this way, it may be fixed.

  Next, as shown in FIG. 1B, the female mold 2a and the male mold 2b are clamped in a state where the main body 1a of the preform molded body 1 is accommodated in the cavity 2c. At this time, the flat skirt 1b is fixed by being sandwiched between mating surfaces formed by clamping the female mold 2a and the male mold 2b as surrounded by a broken line in the drawing. Thus, by fixing the skirt 1b with the mating surface of the female mold 2a and the male mold 2b, the preform molded body 1 is less likely to be displaced. A cavity c is formed by clamping the female mold 2a and the male mold 2b.

  And as shown in FIG.1 (c), the cavity c is filled with the molten resin 5a. Specifically, the injection part 3 of the injection molding machine is advanced, the nozzle 3a is brought into contact with the sprue bush s formed on the male mold 2b, and the molten resin 5a melted in the cylinder 3b is injected by the in-line screw 3c. Thus, the molten resin 5a is filled into the cavity c at a predetermined injection speed.

  Specific examples of the thermoplastic resin to be injected include ABS resins, acrylic resins such as PMMA resins, polystyrene resins, polycarbonate resins, polyolefin resins such as polypropylene, polyethylene terephthalate (PET), and polybutylene. Examples thereof include polyester resins such as terephthalate (PBT), various polyamide resins, and COP resins. Moreover, these may be a compound product in which a filler or the like is blended, or a mixed product in which a plurality of types of resins are alloyed or blended. These are appropriately selected according to the application. For example, as a resin used for a casing of a mobile phone, a mobile device, a home appliance, etc., a resin having excellent impact resistance such as an ABS resin, a polycarbonate resin, and a polyolefin resin such as polypropylene is preferably used.

  The injection molding conditions are conditions that allow complete filling according to the thermal characteristics and melt viscosity of the thermoplastic resin, the shape of the molded body, and the resin thickness (resin temperature, mold temperature, injection pressure, injection speed, holding pressure after injection) , Cooling time) is appropriately set.

  The thickness of the injection-molded article to be molded is not particularly limited, and is appropriately selected according to the application and moldability. For example, when used for a casing of a mobile phone, a mobile device, a home appliance, etc., 0.3 to 3 mm, further 0.5 to 3 mm, and particularly 0.5 to 1.5 mm are selected as a preferable range.

  In the cooling step, after the molten resin 5a is cooled for a predetermined time in the cavity c formed with the female mold 2a and the male mold 2b clamped, as shown in FIG. 1 (d), the female mold The mold 2a and the male mold 2b are opened, and an in-mold molded body 9 in which the molded injection-molded body 5 and the in-mold material 1 laminated on the injection molded body 5 are integrated is taken out. Then, as shown in FIG. 1 (e), the bottom part 1b of the preform molded body 1 is trimmed from the in-mold molded body 9, and the sprue runner 9b of the injection molded body 5 is cut off and removed. A laminated molded body 10 having a simple product shape is obtained.

  Next, the preform molded body used in the method for producing the laminated molded body of the present embodiment will be described in detail.

  As shown in FIG. 2, the preform molded body includes a main body portion 1a formed into a three-dimensional shape and a skirt portion 1b that is finally trimmed and removed. In FIG. 2, the main body portion 1 a has a rectangular basin shape obtained by transversely cutting a box. However, the shape of the main body portion is not limited to such a rectangular basin shape. As long as it has a three-dimensional shape, it is not particularly limited. Moreover, the width | variety of a skirt part will not be specifically limited if it is a width | variety of the grade which can be clamped by the mating surface of a female type | mold and a male type | mold. A boundary line K appears at the boundary between the main body 1a and the skirt 1b.

  Preform molded products are made of leather-like materials such as artificial leather and synthetic leather, fiber structure sheets such as nonwoven fabrics, woven fabrics, woven fabrics and knitted fabrics, and sheet materials such as resin sheets. It is obtained by preform molding which is shaped by molding means such as vacuum / pressure molding. When such a sheet material is shaped, a body part shaped along a predetermined mold for preform molding is formed, and a sheet that is not shaped remains around the body part. Become. A boundary line appears at the boundary between the main body and the skirt.

  The thickness of the sheet material for forming the preform molded body is not particularly limited, but is preferably about 0.1 to 2 mm, and more preferably about 0.2 to 1 mm. When the sheet material is too thin, when the hem of the formed preform is clamped between the mating surfaces of the female mold and the male mold, the hem will not be sufficiently transmitted to the hem. Tend to be difficult.

  In the preform molding, the molding temperature of the sheet material is appropriately selected according to the type of the sheet material, but is (Tg-10) ° C. or higher (Tg + 50) with respect to the glass transition temperature (Tg) of the resin forming the sheet material. ) ° C. or lower, more preferably (Tg−10) ° C. or higher and (Tg + 30) ° C. or lower, particularly preferably (Tg) ° C. or higher and (Tg + 20) ° C. or lower. When the molding temperature of the sheet material is too low, the stretchability tends to decrease, and when the molding temperature of the sheet material is too high, the film tends to be wrinkled due to excessive stretching.

  The preform molded body used in the present embodiment has the following characteristics in relation to an injection mold used for in-mold molding. The shape of the preform molded body used in this embodiment will be described with reference to FIGS.

  FIG. 3 is a schematic perspective view of the cavity forming surface of the female mold 2a and the male mold 2b of the injection mold 2, wherein (a) shows the female mold 2a and (b) shows the male mold 2b. In FIG. 3, 4 is a gate, G2 is a point facing the center of the gate 4 on the surface of the female mold 2b, and B is a boundary line between the cavity 2c and the mating surface 2p on the surface of the female mold 2a. This is a point corresponding to a position on M where the flow length reached by the molten resin flowing in from the gate 4 is the longest. Further, the distance between the point G2 and the point B on the surface of the female mold 2a is L (B).

  FIG. 4 is a schematic perspective view for explaining the positional relationship between the cavity 2c of the female mold 2a of the injection mold and the preform molded body 1 accommodated in the cavity 2c. In FIG. 4, G1 is a point facing the center of the gate 4 on the surface of the preform 1 that faces the surface of the female mold 2a, and A is the side facing the surface of the female mold 2a. This corresponds to the point where the flow length reached by the molten resin flowing in from the gate 4 on the boundary line K between the main body portion 1a and the skirt portion 1b is the longest. In addition, the distance between the point G1 and the point A is L (A). A point A on the preform 1 and a point B on the surface of the female die 2a correspond to the points where the flow length reached by the molten resin flowing in from the gate 4 is the longest. The point G1 on the preform molded body 1 and the point G2 on the surface of the female mold 2a correspond to the center of the gate 4. Further, when the perpendicular Lp is dropped from the center of the gate 4 of the male mold 2b to the cavity 2c of the female mold 2a, the perpendicular Lp passes through the point G1 and the point G2 from the center of the gate 4.

  The preform molded body 1 has a length from the point G1 on the preform molded body 1 to a point A corresponding to the point on the boundary line K corresponding to the point where the flow length of the molten resin filled from the gate 4 reaches the longest. The length L (A) is a length L from the point G2 on the female mold 2a to a point B corresponding to the point on the boundary line M corresponding to the point where the flow length of the molten resin filled from the gate 4 reaches the longest. It is shaped to be smaller than (B). By forming the shape of the preform 1 in this way, the stretched portion has no place to go in the vicinity of the end of the region where the flow length of the molten resin becomes long as shown in FIG. The phenomenon in which W occurs is suppressed.

  FIG. 5 is an explanatory view schematically showing a state in which the molten resin 5a is filled in the cavity c of the injection mold 2 in which the preform molded body 1 is accommodated, from (a) to (c). The state in which the molten resin 5a is filled into the injection cavity c in this order is shown with time. As shown in FIG. 5 (a), the molten resin 5a that has flowed into the cavity c from the gate 4 reaches the points A and B where the flow length reached by the molten resin filled from the gate 4 is longest in the direction of the arrow. Filled in one direction. At this time, the preform 1 is stretched by receiving a shearing force by the flow of the molten resin 5a. Since the skirt 1b of the preform 1 is sandwiched and fixed between the mating surfaces of the female mold 2a and the male mold 2b, the main body 1a has a distal direction in the region where the flow length of the molten resin 5a is increased. Stretches toward. In such a case, as described above, it corresponds to the point where the flow length reached by the molten resin 5a filled from the gate 4 on the boundary line K from the point G1 on the preform molded body 1 is the longest. The length L (A) to the point A is smaller than the length L (B) from the point G2 on the female die 2a to the point B on the boundary line M between the cavity portion 2c and the mating surface 2p. When shaped in this way, as shown in FIG. 5 (a), the main body 1a is arranged in a state where the inside of the cavity is short-cut. And as shown in FIG.5 (b), the extended part of the preform molded object 1 is used in order to extend until it corresponds to the length of length L (B). As a result, as shown in FIG. 5C, when completely filled, the phenomenon that the stretched part loses its place and generates wrinkles near the end of the region where the flow length of the molten resin becomes long is suppressed. The

  The length L (A) from the point G1 to the point A on the preform molded body is 0.5 to 15% shorter than the length L (B) from the point G2 to the point B on the female mold. Preferably, it is 0.6 to 10%, more preferably 0.6 to 5% shorter. When the length L (A) is shorter than the length L (B) by 15% or more, there is a tendency that it is not accurately shaped so as to match the surface shape of the cavity portion of the injection mold. Moreover, when length L (A) is short in the range below 0.5% with respect to length L (B), there exists a tendency for the effect which suppresses wrinkles to fall.

  The mold used for preform molding is usually designed so that the outer surface of the resulting preform molded body exactly matches the surface of the cavity of the female mold of the injection mold. In order to form the length L (A) on the preform molded body shorter than the length L (B) of the surface of the cavity portion of the female mold as in this embodiment, a mold used for preform molding is used. This can be realized by designing the injection mold to be small in size or designing the radius of curvature of the corner portion to be small.

  In the present embodiment, an example in which a square basin-like cavity is formed as an injection mold and one gate is provided at the center of the cavity has been described. However, a plurality of gates may be provided. The gate shape may be any form such as a sprue gate, a pin gate, a fan gate or a film gate. Specifically, for example, in the case of an injection mold 12 having a fan gate 14 as shown in FIG. 7, the center of the fan gate 14 is set as the center of the gate, and G2 and G1 facing the center are set. In addition, the positions corresponding to the farthest point where the molten resin filled from the fan gate 14 reaches can be set as A and B. Further, for example, in the case of an injection mold 22 having two pin gates as shown in FIG. 8, the centers of the two pin gates are the centers of the gates, and G2 and G1 facing each center are represented by G2, G1. The position corresponding to the farthest point where the molten resin filled from the two pin gates reaches can be set as A and B.

  The sheet material for forming the preform molded body preferably has a breaking elongation at 80 ° C. of 110% or more, more preferably 110 to 250%, particularly about 150 to 200%. The shear rate of the molten resin filled in the injection mold in the portion facing the preform molded body is preferably 100 / second or more, and more preferably about 1000 to 10000 seconds / second. When the elongation at break of the sheet material at 80 ° C. is too high, or when the shearing rate of the molten resin is too high, the sheet material tends to be stretched too much and the effect of suppressing wrinkles tends to be reduced. In addition, when the elongation at break of the sheet material at 80 ° C. is too low, or when the shear rate of the molten resin is too low, the sheet material does not stretch, so the surface shape of the cavity part of the injection mold is accurate. There is a tendency not to be shaped.

  The laminated molded body obtained by the manufacturing method of the present embodiment is preferably used for, for example, a mobile phone cover, a smartphone cover, a notebook personal computer decoration material, an automobile interior material, a camera or piano exterior material, a mouse surface decoration material, and the like. Used.

  Hereinafter, the present invention will be described more specifically with reference to examples. The scope of the present invention is not limited by the examples.

  The elongation at break of the sheet material used in this example was measured as follows.

[Elongation at break of sheet material]
A test piece of 100 mm × 25 mm was cut out from the sheet material. And after setting a test piece to the universal testing machine (Instron 5566) provided with the thermostat, and leaving it to stand in the thermostat heated to 80 degreeC for 3 minutes, when a tensile test was done at the tension speed of 500 mm / min The elongation at break was measured.

[Example 1]
Artificial leather with a silver surface of 0.5 mm thickness and a stretch rate of 150% (TD) at 80 ° C (Tillenina made by Kuraray Co., Ltd., ZK-5012: Glass transition at a fineness of 0.09 dtex A sheet having a length of 300 mm and a width of 450 mm was prepared.

  Then, using a vacuum / pneumatic molding machine (manufactured by Fuse Vacuum Co., Ltd., NGF-0406-T), the sheet is heated to 140 ° C., and the main body and the main body stored in the cavity of an injection mold described later A preform molded body was formed by shaping with a preform mold having a concave mold having a peripheral skirt. Specifically, as shown in FIG. 9, the concave mold is a rectangular tray having a length of 150 mm × width of 300 mm × height of 10.0 mm and a rising angle of 90 degrees on the side of the preform molded body with respect to the surface of the injection mold. It was the shape which has a shape-shaped main-body part and shape | molds the preform molded object of the shape chamfered so that a curvature radius might be 6.0 mm in the boundary of a main-body part and a skirt part.

And in-mold shaping | molding was performed using the obtained preform molded object. Specifically, with the female mold and male mold of the injection mold mounted on the injection molding machine (NADEM5000-DM manufactured by Meiki Seisakusho Co., Ltd.) opened, the cavity of the female mold The preform molded body was placed in
Then, the female mold and the male mold were clamped with the skirts sandwiched between the surfaces. The shape of the cavity portion of the injection mold has a rectangular basin-shaped main body portion of 150 mm in length, 300 mm in width, 10.0 mm in height, and a rising angle of 90 degrees, which substantially matches the shape of the preform molded body. Was. The radius of curvature at the boundary between the main body portion and the skirt portion was chamfered to be 5.0 mm. In the cavity portion of the injection mold, two gates were provided at positions symmetrical to each other at positions facing G1 and G1 in FIG. 9B.

  Then, ABS resin (Tg 87 ° C.) was injected and filled into the cavity under the conditions of cylinder temperature 235 ° C., mold temperature 50 ° C., and injection peak pressure 160 MPa. At this time, when the shear rate of the molten resin filled in the injection mold was analyzed by the flow analysis software MOLDFLOW, it was about 2500 / sec in the portion facing the preform molded body. Then, after complete filling, the mold was opened after holding a cooling time of 40 seconds while applying a holding pressure of 20 MPa. And the laminated molded object with which the preform molded object was integrated with the surface of the ABS resin molded object whose average thickness T is 1 mm was obtained.

  L (A) of the preform molded body calculated from the design drawing of the preform mold was 111.0 mm. Moreover, L (B) calculated from the design drawing of the injection mold was 111.8 mm. Therefore, when calculated from (111.0-111.8) /111.8×100, it was formed shorter by 0.7%. And the wrinkle was not seen at all in the obtained laminated molded object.

[Comparative Example 1]
In-mold molding was carried out in the same manner as in Example 1 except that a preform molded body having a chamfered shape so that the radius of curvature was 6.0 mm was used.

  L (A) was 111.4 mm. And L (B) was also 111.4 mm. In the obtained laminated molded body, wrinkles were formed at a plurality of locations in the corner portion.

[Comparative Example 2]
In-mold molding was performed in the same manner as in Example 1 except that a preform molded body having a shape that was chamfered so that the radius of curvature was 5.5 mm was used.

  L (A) of the preform molded body was 111.4 mm. Moreover, L (B) of female type | mold was 111.8 mm. Therefore, when calculated from (111.4-111.8) /111.8×100, it was formed shorter by 0.35%. And in the obtained laminated molded body, wrinkles were formed at a plurality of corner portions.

[Comparative Example 3]
In-mold molding was carried out in the same manner as in Example 1 except that a preform molded body having a chamfered shape so that the radius of curvature was 10.0 mm was used.

  L (A) of the preform molded body was 93.5 mm. Moreover, L (B) of female type | mold was 111.8 mm. Therefore, when calculated from (93.5-111.8) /111.8×100, it was 16.4% shorter. And in the obtained laminated molded body, wrinkles were formed at a plurality of corner portions. Moreover, a part of the injection-molded product was not covered with the preform molded product, and an exposed portion was seen.

[Example 2]
A sheet similar to that in Example 1 was prepared. The sheet was heated to 140 ° C. using a vacuum / pneumatic molding machine (manufactured by Fuse Vacuum Co., Ltd., NGF-0406-T), and the bottom circle diameter 140 mm, as shown in FIG. A preform molded body was formed by shaping with a concave preform mold having a curved surface with a height of 9.0 mm and an angle of 120 ° at the rising portion. 10A is a top view and a schematic cross-sectional view of a preform molded body, and FIG. 10B is a top view and a schematic cross-sectional view of an in-mold molded body to be described later.
Then, in-mold molding was performed using a preform molded body as shown in FIG. Specifically, with the female mold and male mold of the injection mold mounted on an injection molding machine (NADEM5000-DM manufactured by Meiki Seisakusho Co., Ltd.) open, the cavity of the female mold The preform molded body was placed in Then, the skirt of the preform molded body was clamped with the female and male mating surfaces sandwiched. The shape of the cavity of the injection mold is a curved surface having a curved surface with a diameter of the bottom circle of 150 mm, a height of 10.0 mm, and a rising angle of 120 degrees as shown in FIG. there were. The injection molding die is provided with a side gate Gs, and the center of Gs is a position where G1 and G1 in FIG. 10B face the center of Gs.
In-mold molding was performed in the same manner as in Example 1 except that such a preform molded body and an injection mold were used. In this way, a laminated molded body in which the preform molded body was integrated with the surface of the ABS resin molded body having a thickness of 1 mm was obtained. The shear rate of the molten resin filled in the injection mold analyzed by the flow analysis software MOLDFLOW at the portion facing the preform molded body was about 1400 / second.

  L (A) of the preform molded body was 70.8 mm. The L (B) of the female mold for injection molding was 75.9 mm. Therefore, when calculated from (70.8-75.9) /75.9×100, it was 6.7% shorter. And the wrinkle was not seen at all in the obtained laminated molded object.

[Comparative Example 4]
In Example 2, a preform molded body having a main body portion having a curved surface with a diameter of 150 mm, a height of 10.0 mm, and a rising angle of 120 degrees corresponding to the cavity of the injection mold was used. Except that, in-mold molding was performed in the same manner as in Example 2.

  L (A) was 75.9 mm. And L (B) was also 75.9 mm. In the obtained laminated molded body, wrinkles were formed at a plurality of locations in the corner portion.

  ADVANTAGE OF THE INVENTION According to this invention, the lamination molded object which integrated the preform molded object with few generation | occurrence | production of wrinkles can be manufactured.

DESCRIPTION OF SYMBOLS 1 In-mold material 1a Main part 1b Bottom part 2 Injection mold 2a Female mold 2b Male mold 2c Cavity part 2d Core part 3 Injection part main body of injection molding machine 3a Nozzle 3b Cylinder 3c Inline screw 4, 14 Gate 5 Injection molding Body 5a Molten resin 9, 10, 20 Laminated molded body 9b Sprue runner 11 (No hem) preform molded body A Point B corresponding to the farthest point where the molten resin filled from the gate reaches from point G1 The point facing the farthest point where the molten resin filled from the gate reaches from the point G2. C Cavity G1 The point facing the center of the gate on the surface facing the female mold of the preform G2. Point facing the center of the gate on the surface facing the reformed molded body K Boundary line between the body portion 1a and the skirt portion 1b Boundary line w wrinkle between 2c and the mating surface 2p

Claims (3)

A step of preparing a preform molded body having a body portion shaped into a three-dimensional shape and a skirt portion connected to the periphery of the body portion;
The preform molding so that the main body portion is accommodated in the cavity portion in an injection mold including a male die having a core portion and a female die having a cavity portion that accommodates the core portion when clamped. Placing the body;
A step of clamping the female mold and the male mold so that the skirt is sandwiched between mating surfaces in a state where the main body is accommodated in the cavity;
Integrating the injection molded body to be molded and the preform molded body by filling the cavity with molten resin from at least one gate formed in the male mold, and
The preform molded body is
On the surface facing the female mold, from the point G1 facing the center of the gate, the farthest point on the boundary line between the main body part and the skirt part where the molten resin filled from the gate reaches The length L (A) to the point A corresponding to
The point corresponding to the farthest point on the boundary line between the cavity portion and the mating surface at which the molten resin filled from the gate reaches from the point G2 facing the center of the gate on the surface of the female mold A method for producing a laminated molded body, wherein the length L (B) up to B is 0.5 to 15% shorter.   The method for producing a laminated molded body according to claim 1, wherein the preform molded body includes a fiber structure.   The method for producing a laminated molded article according to claim 1 or 2, wherein the sheet forming the preform molded article has a breaking elongation of 110% or more at 80 ° C.

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