JP2013091267A - Die and method for air pressure molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air pressure molding die that is suitable for execution of an air pressure molding method that enables molding of the molded article that has a superior appearance and shaping performance, strength, and a high dimensional accuracy.SOLUTION: The air pressure molding die 30 comprises: an upper die 41 in which an upper mold protrusion 42 projecting toward the lower side is provided at the outer periphery, and has an introduction hole 43 that introduces the compressed gas and; a lower die 51 in which a lower mold protrusion 52 projecting toward the upper side opposing to the upper mold protrusion 42. At mold clamping, the upper mold protrusion 42 and the lower mold protrusion 52 contact through the air pressure molding materials, the upper die 41 includes an upper die movable core 46 that moves vertically and the lower die 51 includes an lower die movable core 56, and at the bottom surface 47 of the upper die movable core 46 opposing to the top face 57 of the lower die movable core 56, a ring shape protrusion 48 analogous to the outer edge of the lower die movable core 56.

Description

  The present invention relates to a pressure forming mold and a pressure forming method.

  As a technique for producing a box-shaped molded article (housing), an injection molding method is currently common. By the way, recent electronic parts and automobile interior parts are strongly required to be thin, light weight, and to have a high-quality design. However, when trying to mold a molded product having a thickness of 1.5 mm or less based on the injection molding method, it often depends on the area of the molded product, but in the cavity provided in the mold used in the injection molding method. Cannot be completely filled with molten thermoplastic resin. As a method for solving such a problem, there is a method of using a thermoplastic resin having a low molecular weight and an excellent filling property, but problems such as cracking of a molded product due to insufficient toughness have occurred. Another method is to increase the number of gate points and shorten the flow distance when filling the thermoplastic resin into the cavity, but there are many weld lines, the strength is reduced, and the appearance is poor. Is invited.

Japanese Patent Laid-Open No. 10-166436 Japanese Patent Application Laid-Open No. 08-052796

  As a method for solving the problems in the injection molding method and producing a box-shaped molded product, a compressed air molding method can be considered. The pressure forming method is known from, for example, Japanese Patent Laid-Open Nos. 10-166436 and 08-052796. However, although the compressed air molding method is applied to the molding of miscellaneous goods, food containers, and lamp covers, from the viewpoint of the appearance, formability, strength, and dimensional accuracy of the molded product, electronic equipment, electronic components, and automobile interiors are used. Examples applied to the molding of parts and the like are not known as long as the present inventors have investigated.

  Accordingly, an object of the present invention is to provide a compressed air molding method that enables molding of a molded article having excellent appearance, formability, strength, and high dimensional accuracy, and a compressed air molding metal suitable for execution of the compressed air molding method. To provide a mold.

In order to achieve the above-mentioned object, the pressure molding die of the present invention is
An upper mold protrusion that protrudes toward the lower side is provided on the outer periphery, and an upper mold having an introduction hole for introducing compressed gas, and
A lower mold provided with a lower mold projecting portion on the outer peripheral portion facing the upper mold projecting portion and projecting upward.
A pressure forming mold in which the upper mold protrusion and the lower mold protrusion are in contact with each other via a pressure forming material during mold clamping,
The upper mold is equipped with an upper mold movable core that moves up and down,
The lower mold is equipped with a lower mold movable core that moves up and down,
A ring-shaped protrusion similar to the outer edge portion of the lower mold movable core portion is provided on the bottom surface of the upper mold movable core portion facing the top surface of the lower mold movable core portion.

In order to achieve the above object, the compressed air molding method of the present invention comprises:
An upper mold protrusion that protrudes toward the lower side is provided on the outer periphery, and an upper mold having an introduction hole for introducing compressed gas, and
A lower mold provided with a lower mold projecting portion on the outer peripheral portion facing the upper mold projecting portion and projecting upward.
Consisting of
The upper mold is equipped with an upper mold movable core that moves up and down,
The lower mold is equipped with a lower mold movable core that moves up and down,
Use a pressure molding die that has a ring-shaped protrusion similar to the outer edge of the lower mold core on the bottom of the upper mold core that faces the top surface of the lower mold core. A compressed air forming method,
The upper mold movable core part is arranged on the upper side, the lower mold movable core part is arranged on the lower side, the pressure molding material is arranged on the lower mold projection, and the pressure molding material is heated.
After the upper mold and the lower mold are clamped and the upper mold protrusion and the lower mold protrusion are in contact with each other via the heated pressure forming material,
Lowering the upper mold movable core part, raising the lower mold movable core part, sandwiching the compressed air molding material between the upper mold movable core part and the lower mold movable core part, and then the compressed air molding material to the upper mold movable core part and While sandwiched between the lower mold movable core part, lower the upper mold movable core part and the lower mold movable core part to the lowest position,
Introduce compressed gas from the introduction hole to shape the material for compressed air molding,
It consists of each process.

In the compressed air molding method of the present invention, the pressure of the compressed gas is preferably 1 × 10 ⁶ Pa to 5 × 10 ⁶ Pa. Although air can be illustrated as compressed gas, it is not limited to this, For example, nitrogen gas etc. can also be used.

The pressure forming mold used in the pressure forming method of the present invention including the above preferred form or the pressure forming mold of the present invention (hereinafter collectively referred to as “for the pressure forming of the present invention”). Called "molds")
The lower mold is provided with a lower mold movable core section storage section and a void section communicating with the lower mold movable core section storage section.
When the lower mold movable core part is lowered to the lowest position, the lower mold movable core part is stored in the lower mold movable core part storage unit,
When the upper mold movable core portion is lowered to the lowest position, it is preferable that the side surface of the upper mold movable core portion and the side surface of the void portion face each other. And in the compressed air molding method of the present invention including such a preferred form,
In the step of forming the compressed air molding material by introducing compressed gas from the introduction hole, the compressed air molding material portion positioned between the side surface of the upper mold movable core portion and the side surface of the cavity portion, Compressed gas is introduced between the side surface of the mold movable core part, so that the portion of the compressed air molding material located between the side surface of the upper mold movable core part and the side surface of the cavity part is the cavity part. It is preferable that the side surface is pressed.

  Further, in the pressure forming mold or the like of the present invention including the above preferred configuration, when the pressure forming material is sandwiched between the upper mold movable core part and the lower mold movable core part, the bottom surface of the upper mold movable core part It is desirable that there be a gap between the pressure moldable material portion located on the top surface of the lower mold movable core portion. The presence of the gap eliminates the contact between the bottom surface of the upper mold movable core portion and the compressed air molding material, and the portion of the compressed air molding material located on the top surface of the lower mold movable core portion and the lower mold As a result of preventing the compressed gas from being caught between the top surface of the movable core portion, a more excellent appearance can be imparted to the molded product. Examples of the gap include 0.5 mm to 5 mm.

  In the pressure forming mold or the like of the present invention including the preferred configuration described above, a peeling promoting layer can be formed on the top surface of the lower mold movable core portion. The peeling promoting layer is a group consisting of a SiC layer, a TiC layer, a TiN layer, a CrN layer, a DLC layer, a TiAlN layer, a TiSin layer, an AlCrN layer, a CrSiN layer, a TiBN layer, an AlCrSiN layer, an AlZrN layer, an AlZrSiN layer, and a CrBN layer. It can be set as the form which consists of at least 1 layer selected from these. As a result, the molded product can be easily peeled off from the top surface of the lower mold movable core portion. As a result, it is possible to mold a molded product having an excellent appearance and high dimensional accuracy.

Furthermore, in the compressed air molding die of the present invention including the preferred configuration and form described above, a mat treatment is applied to at least a part of the top surface of the lower mold movable core portion in contact with the compressed air molding material. It can be set as the applied form. As a result, the mat pattern formed on at least a part of the top surface of the lower mold movable core portion in contact with the pressure molding material can be transferred to the pressure molding material, and from the top surface of the lower mold movable core portion. As a result of being able to easily peel off the molded product, it becomes possible to mold a molded product having an excellent appearance and high dimensional accuracy. In order to perform the matting treatment, glass beads, ceramic particles, or the like may be sprayed onto the top surface of the lower movable core portion using a sandblasting device using compressed air having a pressure of about 0.2 MPa. As the surface roughness, Rz defined by JIS B-0601: 2001 can be in the range of 3 μm to 50 μm, and a preferable mat pattern texture can be obtained. In this time of transferring the mat pattern on the pressure molding material as, the temperature of the lower mold movable core portion in contact with the pressure molding material, it is preferable that the glass transition temperature T _g or more pressure molding material. Here, when the pressure forming material has a laminated structure of, for example, an acrylic resin layer (specifically, for example, a PMMA resin layer) and a polycarbonate resin layer, a mat pattern is imparted to the PMMA resin layer. In this case, the glass transition temperature of the PMMA resin may be 105 ° C. or higher. When a mat pattern is applied to the polycarbonate resin layer, the glass transition temperature of the polycarbonate resin may be 145 ° C. or higher. Alternatively, when the pressure forming material is a single polycarbonate resin layer, the glass transition temperature of the polycarbonate resin may be 145 ° C or higher. And since compressed gas is introduce | transduced from an introducing hole and a pressure forming material is shaped, the whole molded article can be easily cooled with compressed gas.

  In the compressed air molding method of the present invention including the preferred configuration and form described above, the compressed air molding material preferably has a polycarbonate resin layer. In this case, the compressed air molding material includes an acrylic resin layer and a polycarbonate. It is preferable to have a laminated structure of resin layers. Further, in these cases, at least a part of the outer surface of the polycarbonate resin layer (for example, the surface constituting the inner surface of a molded product having a box shape) is printed. It is preferable. In these cases, it is preferable that the polycarbonate resin layer is in contact with the upper movable core portion. Alternatively, the pressure forming material is an acrylic resin layer having a thickness of 50 μm to 120 μm on one surface of the polycarbonate resin layer. Are laminated by coextrusion, the total thickness is preferably 0.5 mm to 1.5 mm, and the acrylic hardness of the acrylic resin layer is preferably 2H or more. A hard coat layer may be formed on the acrylic resin layer. The hard coat layer may be formed on the pressure forming material before being used for molding, or may be performed on a molded product.

The molded product obtained by the compressed air molding method of the present invention is, for example,
A bottom surface having a rectangular planar shape, and a side surface extending upward from the outer edge of the bottom surface, is a seamless (seamless) box-shaped molded article,
The vertical length of the bottom surface is 1 cm to 1 m, preferably 5 cm to 35 cm, and the horizontal length is 1 cm to 80 cm, preferably 5 cm to 35 cm.
The thickness of the bottom surface is 0.5 mm to 1.5 mm, preferably 0.7 mm to 1.2 mm.
The pencil hardness of the outer surface is 2H or higher, preferably 3H or higher,
The amount of warpage is 0.4 mm or less, preferably 0.3 mm or less.

  For example, the molded product has a box shape as described above. That is, the appearance of the molded product is, for example, a rectangular parallelepiped, but the portion where the side surface and the side surface intersect may be rounded. That is, the bottom surface has a rectangular planar shape, but the four corners of the rectangular planar shape may be rounded. In addition, a portion where the bottom surface and the side surface intersect may be rounded.

As described above, the molded product can be formed from a polycarbonate resin, and further, from a material having a laminated structure of an acrylic resin layer located outside and a polycarbonate resin layer located inside. In this case, the thickness of the acrylic resin layer is preferably 50 μm to 120 μm, and in these cases, the surface of the polycarbonate resin layer (for example, a box-like shape) It is preferable that at least a part of the inner surface) of the molded product having a print is printed. The polycarbonate resin preferably has high toughness, and specifically, the Charpy impact strength (with notch) specified in ISO 179 preferably has a value of 50 kJ / m ² or more. The number average molecular weight of the polycarbonate resin is desirably 2 × 10 ⁴ or more. PMMA has a Charpy impact strength of ² kJ / m ² or less, and a highly fluid polycarbonate resin has a Charpy impact strength of 9 kJ / m ² or less.

  Electronic products, electronic parts, and automobile interior parts can be constructed from molded products. Specifically, in addition to mobile phone and smartphone cases, personal computer cases including tablets, PDAs (portable information terminals, Personal Digital Assistant) housing, portable music player housing, game console housing, electronic book housing, electronic dictionary housing, digital camera and video camera housing, television receiver housing Examples include a body, a control panel such as a heater for an automobile, switches, and a wood grain case. When configuring the case of a mobile phone or smartphone from a molded product, the transparent window part provided on the case is configured from the transparent part of the molded product, and the other part of the housing is printed on the molded product. In this case, for example, the surface of the polycarbonate resin layer may be printed using black ink. Since the printed surface of the polycarbonate resin layer is viewed through the transparent acrylic resin layer, the appearance of the printed surface is remarkably improved. Note that a liquid crystal display device, an organic electroluminescence display device, and the like are usually disposed below the transparent window portion provided in the housing. You may press-process or NC process a molded article, and may process to a desired external shape, a hole part, etc.

  The molded product can be configured to have a box-shaped substrate inside. Here, examples of the material constituting the substrate include aluminum and an aluminum alloy. Alternatively, examples of the substrate include a molded product made and molded from a thermoplastic resin based on an injection molding method. You can also. In this case, the back surface of the molded product may be bonded to a substrate (which may be box-shaped or not box-shaped) using an adhesive or a pressure-sensitive adhesive, or an ultrasonic wave You may adhere | attach based on the joining method. By providing the box-shaped base with a protrusion, a snap, a notch, a recess, a stamping structure, and the like, attachment to other parts, fitting with other parts, and the like can be easily performed. As a result, ASSY (assembly) can be achieved.

  The pencil hardness may be measured according to JIS K5600-5-4: 1999. The warpage may be measured on the bottom surface of the molded product. The flatness after leaving in an environment of 23 ° C. and 50% relative humidity for 24 hours (according to JIS B 0419-1991) and 85 ° C. This is the amount of change from the flatness after leaving for 4 hours in an environment of 23 ° C. and 50% relative humidity after performing an environmental test at 85% relative humidity for 120 hours.

  The vertical movement of the upper mold movable core section and the lower mold movable core section and the vertical movement of the upper mold can be performed using, for example, a hydraulic cylinder or a pneumatic cylinder. The pressure forming material may be heated using, for example, a heater. The pressure forming mold itself has a well-known configuration and structure, and may be made of a well-known material such as aluminum, aluminum alloy, carbon steel, etc., and from the viewpoint of durability, it is made of carbon steel. Is preferred. What is necessary is just to produce the upper mold | type movable core part containing a ring-shaped projection part, and a lower mold | type movable core part from the same material as the material which comprises a pressure die, for example.

  In the pressure forming mold or the pressure forming mold used in the pressure forming method of the present invention, the upper mold movable core part and the lower mold movable core part are provided, and when the molded product is molded, the upper mold is movable. Since the compressed air molding material is sandwiched between the core part and the lower mold movable core part, it becomes possible to mold a molded product having excellent shapeability, excellent appearance, high printing position accuracy, and high dimensional accuracy. Moreover, since the degree of freedom of selection of the material constituting the molded product is high, a material having high strength can be selected, and a molded product having high strength can be formed. In addition, since a compressed gas having a lower pressure can be used, high safety can be obtained, and the mold strength can be lowered, so that it is possible to reduce the mold manufacturing cost.

FIG. 1 is a schematic end view of the pressure forming mold of Example 1 when the mold is opened. FIG. 2 is an end view of a pressure forming mold or the like for explaining the pressure forming method of the first embodiment. FIG. 3 is an end view of a pressure forming mold or the like for explaining the pressure forming method of the first embodiment, following FIG. FIG. 4 is an end view of a pressure forming mold or the like for explaining the pressure forming method of Example 1 following FIG. FIG. 5 is an end view of a pressure forming mold or the like for explaining the pressure forming method of the first embodiment, following FIG. 4. FIG. 6 is an end view of a pressure forming mold or the like for explaining the pressure forming method of the first embodiment, following FIG. 5. FIG. 7 is an end view of a pressure forming mold or the like for explaining the pressure forming method of Example 1 following FIG. FIG. 8 is an end view of a pressure forming mold and the like for explaining the pressure forming method of Example 1 following FIG. FIGS. 9A and 9B are a schematic cross-sectional view of the molded product of Example 1 and a schematic plan view of the molded product before processing into a desired outer shape, respectively. FIG. 10 is a schematic end view of the pressure forming mold of Example 2 when the mold is opened. 11A and 11B are schematic cross-sectional views of the molded articles of Example 5 and Example 6, respectively.

  Hereinafter, the present invention will be described based on examples with reference to the drawings. However, the present invention is not limited to the examples, and various numerical values and materials in the examples are examples.

  Example 1 relates to a pressure forming mold of the present invention and a pressure forming method of the present invention.

  The molded product 10 in Example 1 or Examples 2 to 6 described later has a bottom surface 11 having a rectangular planar shape, and a side surface 12 extending upward from an outer edge portion of the bottom surface 11 and is seamless (seamless). A) box-shaped molded product. The vertical length of the bottom surface 11 is 1 cm to 1 m, preferably 5 cm to 35 cm, the horizontal length is 1 cm to 80 cm, preferably 5 cm to 35 cm, and the thickness of the bottom surface is 0.5 mm to 1.5 mm, preferably 0.7 mm to 1.2 mm, the pencil hardness of the outer surface is 2H or more, preferably 3H or more, and the amount of warpage is 0.4 mm or less, preferably 0.3 mm or less. More specifically, the vertical length (outer dimension) of the bottom surface 11 is 114.0 mm, the horizontal length (outer dimension) is 54.0 mm, and the thickness of the bottom surface 11 and the side surface 12 is as follows. 1.0 mm. A portion where the side surface 12 and the side surface 12 intersect is rounded, and a portion where the bottom surface 11 and the side surface 12 intersect is also rounded. The radius of roundness was 1.5 mm. A schematic cross-sectional view of the molded product 10 in Example 1 or Examples 2 to 4 described later is shown in FIG.

  The molded product 10 in Example 1 or Example 2 to Example 6 described later is molded from a compressed air molding material 21 having a laminated structure of an acrylic resin layer located outside and a polycarbonate resin layer located inside. ing. The acrylic resin layer preferably has a thickness of 50 μm to 120 μm. Specifically, the acrylic resin layer has a thickness of 0.06 mm, and the polycarbonate resin layer has a thickness of 0.94 mm. . Further, at least a part (specifically, a part) of the surface of the polycarbonate resin layer is printed using black ink. A case of a smartphone is configured from the molded product 10 in Example 1 or Example 2 to Example 6 described later. Here, the molded product (housing) 10 is provided with a transparent window portion 13, and the window portion 13 is formed of a transparent portion of the pressure forming material 21. Further, the other part of the molded product (housing) 10 is composed of a printed part (printed part 14) of the compressed air molding material 21. After assembling the final molded product, a liquid crystal display device or the like is disposed below the transparent window portion 13 via a PET film with an ITO electrode having a touch panel function and an OCA (Optical Clear Adhesive) tape. An organic electroluminescence display device is arranged.

  In Example 1 or Examples 2 to 6 described later, the compressed air molding material 21 has a laminated structure of an acrylic resin layer and a polycarbonate resin layer as described above, and at least a part of the outer surface of the polycarbonate resin layer. (Specifically, a part of the outer surface) is printed in advance. The polycarbonate resin layer is disposed so as to be in contact with the upper mold movable core portion 46, and the acrylic resin layer is disposed in contact with the lower mold movable core portion 56. The pressure forming material 21 is formed by laminating an acrylic resin layer having a thickness of 50 μm to 120 μm on one surface of a polycarbonate resin layer by coextrusion, and has a total thickness of 0.7 mm to 1.5 mm. The pencil hardness of the system resin layer is 2H or more, and more specifically as described above.

As shown in the schematic end view of FIG. 1 in a state where the mold is opened, the pressure forming mold 30 of Example 1 is
The upper mold | type protrusion part 42 which protruded toward the lower side is provided in the outer peripheral part, The upper mold | type 41 which has the introduction hole 43 which introduces compressed gas, and
A lower mold 51 having a lower mold protrusion 52 that protrudes upward facing the upper mold protrusion 42 on the outer periphery,
This is a pressure forming mold in which the upper mold projecting portion 42 and the lower mold projecting portion 52 are in contact with each other via the compressed air molding material 21 during mold clamping. And
The upper mold 41 is provided with an upper mold movable core portion 46 that moves up and down.
The lower mold 51 is provided with a lower mold movable core portion 56 that moves up and down.
On the bottom surface 47 of the upper mold movable core portion 46 facing the top surface 57 of the lower mold movable core portion 56, a ring-shaped projection 48 similar to the outer edge portion of the lower mold movable core portion 56 is provided.

In the pressure forming mold of Example 1,
The lower mold 51 is provided with a lower mold movable core section storage section 54 and a void section 53 that is located above the lower mold movable core section storage section 54 and communicates with the lower mold movable core section storage section 54. And
When the lower mold movable core part 56 is lowered to the lowest position, the lower mold movable core part 56 is stored in the lower mold movable core part storage part 54,
When the upper mold movable core portion 46 is lowered to the lowest position, the side surface 46A of the upper mold movable core portion 46 and the side surface 53A of the void portion 53 face each other.

  Further, when the compressed air molding material 21 is sandwiched between the upper mold movable core portion 46 and the lower mold movable core portion 56, it is positioned on the bottom surface 47 of the upper mold movable core portion 46 and the top surface 57 of the lower mold movable core portion 56. There is a gap between the compressed air molding material 21 portion. The gap corresponds to the height of the ring-shaped protrusion 48.

The compressed gas is made of air, and the introduction hole 43 is connected to an air compressor (not shown) through a pipe (not shown). The vertical movement of the upper mold 41 and the vertical movement of the upper mold movable core part 46 can be performed using a first hydraulic cylinder and a second hydraulic cylinder 31 (not shown), and the vertical movement of the lower mold movable core part 56 is This can be done using the third hydraulic cylinder 33. Reference numeral 32 is oil for driving the second hydraulic cylinder 31, and reference numeral 34 is oil for driving the third hydraulic cylinder 33. The pressure forming material 21 may be heated using a heater (not shown). The pressure forming mold 30 itself has a known configuration and structure, and is made of carbon steel. The upper mold movable core section 46 including the ring-shaped protrusion 48 and the lower mold movable core section 56 are made of the same material as that constituting the pressure forming mold 30. The size of the lower mold movable core portion 56 is 112.0 mm × 52.0 mm. Moreover, the outer dimension of the ring-shaped protrusion 48 provided on the bottom surface 47 of the upper movable core 46 is also 112.0 mm × 52.0 mm. The height of the ring-shaped protrusion 48 was 2.0 mm. The planar shape of the ring-shaped protrusion 48 is a “B” shape. Further, as shown in FIG. 5, the distance (interval, L _S ) of the gap between the side surface 46A of the upper mold movable core portion 46 and the side surface 53A of the void portion 53 was set to L _S = 1.0 mm. When the thickness of the molded product to be molded (or the thickness with some clearance) is t _S , the value of (L _S −t _S ) is specifically 0 mm to 0.5 mm. Can be illustrated.

  Hereinafter, the pressure forming method of Example 1 will be described. Prior to the description, first, the manufacture of the pressure forming material 21 used in Example 1 or Examples 2 to 6 described later will be described.

An extrusion molding machine (main extruder) for extruding polycarbonate resin was used with a barrel diameter of 65 mm and a screw length / diameter ratio of 35, and the cylinder temperature was 270 ° C. In addition, as an extrusion molding machine (sub-extrusion machine) for extruding the acrylic resin layer constituting the coating layer, one having a barrel diameter of 32 mm and a screw length / diameter ratio of 32 is used, and the cylinder temperature is set to 250 ° C. did. A feed block was used to melt and extrude two types of resins at the same time and laminate them. The product name: Iupilon E-2000 (number average molecular weight: 2.8 × 10 ⁴ ) manufactured by Mitsubishi Engineering Plastics Co., Ltd. was used as the polycarbonate resin. And the acrylic resin layer was laminated | stacked on the single side | surface of the polycarbonate resin layer. The temperature in the die head was set to 260 ° C., and the resin laminated and integrated in the die was guided to three polishing rolls having a mirror-finished horizontal arrangement. The temperature of the first roll was set to 110 ° C, the temperature of the second roll was set to 140 ° C, and the temperature of the third roll was set to 185 ° C. And after forming the bank between the 1st roll and the 2nd roll, it passed between the 2nd roll and the 3rd roll. A co-extruded sheet (pressure-air forming material 21) having a thickness of 1.0 mm was extruded at a take-up speed of 1.5 m / min. At this time, the rotation speed of the main extruder and the sub-extruder was set so that the discharge amount ratio was main extruder / sub-extruder = 470/30. In addition, the thickness of the acrylic resin layer in the 1.0 mm-thick coextruded sheet (pressure-air forming material 21) was 60 μm.

  Screen printing using IPX-HF ink (black ink) manufactured by Teikoku Ink Co., Ltd. was performed on the polycarbonate resin layer side of the compressed air molding material 21 thus obtained. After heating and curing at 80 ° C., Four pin fixing holes 22 (see FIG. 9B) were provided.

  Hereinafter, the compressed air forming method of Example 1 will be described with reference to FIGS. A pressure forming mold 30 is attached to a pressure forming machine (manufactured by NK Enterprise Co., Ltd.). The pressure forming machine is composed of a carry-in zone, a heating zone, a press zone, and a carry-out zone. The same applies to the following embodiments.

[Step-100]
First, the upper mold movable core part 46 is disposed on the upper side, the lower mold movable core part 56 is disposed on the lower side, and the compressed air molding material 21 is disposed on the lower mold projecting part 52. Specifically, a pin 55 that fits into a pin fixing hole 22 provided in the compressed air molding material 21 is provided in the lower mold protrusion 52. The upper mold projecting portion 42 is provided with a fitting portion 45 including a hole that fits with the pin 55. A continuous groove portion (not shown) is provided in each of the lower mold protrusion 52 portion outside the pin 55 and the upper mold protrusion portion 42 outside the fitting portion 45. An “O” ring (not shown) is inserted, and when the upper mold protrusion 42 and the lower mold protrusion 52 are in contact with each other, a sealed state can be maintained. Then, in the carry-in zone of the compressed air molding machine, for example, the operator fits the pin 55 provided in the lower mold protrusion 52 into the pin fixing hole 22 provided in the compressed air molding material 21, so that the compressed air is compressed. The molding material 21 is disposed on the lower mold protrusion 52 (see FIG. 2). The compressed air molding material 21 is disposed on the lower mold protrusion 52 so that the polycarbonate resin layer of the compressed air molding material 21 faces the upper mold movable core portion 46 and the acrylic resin layer contacts the lower mold movable core portion 56. To do. The mold temperature was set to 80 ° C. Then, the lower mold 51 provided with the pressure forming material 21 is conveyed to the heating zone of the pressure forming machine, and the pressure forming material 21 is heated to 150 ° C. by a heater (not shown). The lower mold movable core part 56 may be stored in the lower mold movable core part storage part 54, or may be raised to the extent that it does not contact the compressed air molding material 21.

[Step-110]
In the press zone of the pressure forming machine, the upper mold movable core portion 46 is disposed above, and the upper mold 41 is also disposed above. Then, the lower mold 51 provided with the pressure forming material 21 is conveyed to the press zone (see FIG. 3), and the first hydraulic cylinder is operated to lower the upper mold 41. In this way, the upper mold 41 and the lower mold 51 are clamped, and the upper mold protrusion 42 and the lower mold protrusion 52 are brought into contact with each other via the heated pressure-air forming material 21 to form a sealed state ( (See FIG. 4).

[Step-120]
Thereafter, the second hydraulic cylinder 31 is operated to lower the upper mold movable core portion 46, the third hydraulic cylinder 33 is operated to raise the lower mold movable core portion 56, and the compressed air molding material 21 is moved to the upper mold movable core. It sandwiches between the part 46 and the lower mold movable core part 56 (see FIG. 5). Next, the second hydraulic cylinder 31 and the third hydraulic cylinder 33 are operated in a state where the compressed air molding material 21 is sandwiched between the upper mold movable core section 46 and the lower mold movable core section 56, and the upper mold movable core section 46 and Lower mold movable core portion 56 is lowered to the lowest position (see FIG. 6).

[Step-130]
Thereafter, compressed gas (compressed air, pressure is 2 × 10 ⁶ Pa) is introduced from the introduction hole 43 for 2 seconds to perform pressure forming, and shape the pressure forming material 21 (see FIG. 7). . In this process, the portion of the pressure forming material 21 located between the side surface 46A of the upper mold movable core portion 46 and the side surface 53A of the void portion 53 and the side surface 46A of the upper mold movable core portion 46 are included. In between, compressed gas is introduced. As a result, the portion of the compressed air molding material 21 located between the side surface 46 A of the upper mold movable core portion 46 and the side surface 53 A of the void portion 53 is pressed against the side surface 53 A of the void portion 53.

[Step-140]
Thereafter, the second hydraulic cylinder 31 is operated to move the upper mold movable core portion 46 upward, and further, the first hydraulic cylinder is operated to move the upper mold 41 upward to open the mold (see FIG. 8). . FIG. 9B shows a schematic plan view of the molded product in this state (molded product before processing into a desired outer shape). Then, the lower mold 51 on which the compressed air molding material 21 (molded product 10) is arranged is carried out to the carry-out zone of the compressed air molding machine, and the compressed air molding material 21 (molded product 10) is removed from the lower mold. Thereafter, the molded product is subjected to press processing, and processing (punching) into a desired outer shape is performed to complete the molded product.

  The obtained molded product had an extremely high formability similar to that of an injection molded product, and the shape of the void portion 53 was transferred to the extent that an edge appeared at a portion where the bottom surface and the side surface intersected. Moreover, it had a very deep appearance. Although the acrylic resin layer was provided on the front side, the molded product could be stamped without cracking because it was a laminate with the polycarbonate resin layer. Moreover, because it uses a polycarbonate resin with a high molecular weight, it has a high rigidity without being cracked even if it is bent by hand, even though it is 1 mm thick (side thickness is 0.6 mm). Had. Further, since the acrylic resin layer was provided on the front side, the pencil hardness was “2H” and had a very excellent surface hardness. Further, no deformation or misalignment of the applied printing occurred.

As Comparative Example 1, the execution of [Step-120] in Example 1 was omitted. That is, following [Step-110] of the first embodiment (however, the lower mold movable core portion 56 remains in the state shown in FIG. 2), similarly to [Step-130] of the first embodiment, the introduction. Compressed gas (compressed air, pressure 2 × 10 ⁶ Pa) was introduced from the holes 43 for 2 seconds to perform pressure forming, and the pressure forming material 21 was shaped. The obtained molded product of Comparative Example 1 had poor transfer at the portion where the bottom surface and the side surface crossed, and the edge was rounded. Further, the printing was extended within a range of about 20 mm from the outer periphery of the molded product, and a large deviation occurred.

  In the compressed air forming mold or the compressed air forming mold used in the compressed air forming method of Example 1, the upper mold movable core part and the lower mold movable core part are provided, and at the time of molding the molded product, Since the pressure molding material is sandwiched between the upper mold movable core section and the lower mold movable core section, it is possible to mold a molded product having excellent shapeability, excellent appearance, high printing position accuracy, and high dimensional accuracy. Moreover, since the degree of freedom of selection of the material constituting the molded product is high, a material having high strength can be selected, and a molded product having high strength can be formed. In addition, since a compressed gas having a lower pressure can be used, high safety can be obtained, and the mold strength can be lowered, so that it is possible to reduce the mold manufacturing cost.

  The second embodiment is a modification of the first embodiment. In Example 2 whose schematic end view is shown in FIG. 10, the exfoliation promotion composed of a TiN layer having a thickness of 1 μm formed by sputtering on the top surface 57 of the lower mold movable core portion 56. Layer 60 is formed. Except for this point, the compressed air molding die of Example 2 has the same configuration and structure as the compressed air molding die of Example 1, and thus detailed description thereof is omitted.

  In Example 2, the mold temperature was set to 130 ° C. in the same process as [Process-100] of Example 1. Further, the pressure forming material 21 was heated to 135 ° C. with a heater. Except for the above points, the pressure forming method of the second embodiment can be the same as the pressure forming method of the first embodiment, and a detailed description thereof will be omitted.

  In Example 2, since the mold temperature was set higher than in Example 1, the formability was further improved. In addition, since the peeling promoting layer is formed on the top surface of the lower mold movable core portion, the releasability is very high, and the entrainment of compressed gas was not observed during the pressure forming.

The third embodiment is a modification of the first to second embodiments. In Example 3, the surface of the acrylic resin layer of the obtained molded product was coated with an ultraviolet curable acrylic resin hard coating agent with a spray gun so that the coating thickness was about 5 μm. went. Then, after drying at 80 ° C., using a high-pressure mercury lamp with an output of 80 W / cm ² , the hard coat agent was cured by irradiating with ultraviolet rays at a position of 12 cm under the light source at a conveyor speed of 1.5 m / min. The molded product thus obtained had a pencil hardness of “5H”.

  The flatness of the molded article obtained in Examples 1 to 3 and the compressed air molding material used in an environment of 23 ° C. and 50% relative humidity for 24 hours is shown in JIS B0149-1991. In conformity, the measurement was performed with a three-dimensional measuring machine. Thereafter, an environmental test of 85 ° C. and a relative humidity of 85% for 120 hours was performed on the molded article and the pressure molding material, and then left in an environment of 23 ° C. and a relative humidity of 50% for 4 hours. Later flatness was measured with a three-dimensional measuring machine. Then, the amount of change in flatness was obtained as “warp”. The amount of change in Examples 1 to 3 was 0.2 mm or less. In addition, although the shape of the sheet-like pressure forming material changes greatly due to environmental changes, it has been found that the shape is hardly changed by environmental changes by molding into a box-shaped molded product.

The fourth embodiment is a modification of the first to third embodiments. In the fourth embodiment, the mat is formed on at least a part of the top surface 57 of the lower mold movable core portion 56 in contact with the compressed air molding material 21 (specifically, in the fourth embodiment, specifically, the entire top surface 57). Processing has been applied. In order to perform the matting treatment, glass beads, ceramic particles, and the like were sprayed onto the top surface 57 of the lower movable core portion 56 using a sand blast apparatus using compressed air having a pressure of about 0.2 MPa. The matte treatment was performed so that the surface roughness Rz defined by JIS B-0601: 2001 was 20 μm. In addition, when the mat pattern is transferred to the pressure forming material 21, that is, in the same step as [Step-120] in the first embodiment, the lower mold movable core portion 56 in contact with the pressure forming material 21 is used for pressure forming. material the glass transition temperature T _g above, specifically, a glass transition temperature of a is 105 ° C or more acrylic resins, and more specifically, was 120 ° C. As a result, the mat pattern formed on the top surface 57 of the lower mold movable core portion 56 in contact with the compressed air molding material 21 could be transferred to the acrylic resin layer of the compressed air molding material 21, and a preferred mat pattern. In addition, the molded product can be easily peeled from the top surface 57 of the lower mold movable core portion 56. As a result, it is possible to mold a molded product having an excellent appearance and high dimensional accuracy. became.

  The fifth embodiment is a modification of the first to fourth embodiments. As shown in a schematic cross-sectional view in FIG. 11A, in Example 5, an assembly part for incorporating the molded product of Example 1 to Example 4 into another member or another part was produced. . That is, the molded product of Example 5 includes a box-shaped base 15 inside. Specifically, the base 15 made of an injection-molded product having a size of 52.0 mm × 112.0 mm and a thickness of 2.0 mm so as to match the inner shape of the molded product of Examples 1 to 4. An injection mold was obtained so that A boss 16 was provided on the base 15 for incorporation into another member or another part. The planar shape of the base body 15 is a “B” shape.

  A polycarbonate resin (H3000 manufactured by Mitsubishi Engineering Plastics Co., Ltd.) was used as a molding material for the substrate 15. The molding shrinkage ratio is 5/1000, and no gap is produced even after assembling the base body 15 and the molded products of Examples 1 to 4.

Using J110AD manufactured by Nippon Steel Works as an injection molding machine, injection molding is performed at a resin temperature of 280 ° C., a mold temperature of 80 ° C., and an injection pressure of 8 × 10 ⁷ Pa to obtain a base body (injection molded product) 15. It was. The obtained base | substrate 15 and the molded article shape | molded in Example 1- Example 4 were joined using the acrylic type ultraviolet curing adhesive. In order to cure the acrylic ultraviolet curable adhesive, a high pressure mercury lamp with an output of 80 W / cm ² was used, and ultraviolet rays were irradiated at a position of 12 cm under the light source at a conveyor speed of 1.5 m / min. The molded product was firmly bonded to the base body 15, and assembly with another member or another part became possible.

  The sixth embodiment is a modification of the fifth embodiment. A schematic cross-sectional view of the molded product of Example 6 is shown in FIG. 11B, and the molded product of Example 6 also has a box-shaped substrate 17 inside. Specifically, the base body 17 is made in advance from aluminum or an aluminum alloy, or is made in advance from a thermoplastic resin based on, for example, an injection molding method. A recess 18 having a width of 1.0 mm and a depth of 0.5 mm is provided around the outer side surface of the base body 17. The side surface of the molded product of Example 6 is recessed following this recess 18. A cutout portion 19 is provided on the inner surface of the base body 17. By fitting the cutout portion 19 with a projection of another component, it is possible to assemble the molded product and the separate component. In addition, although the back surface of the molded product was bonded to the base body 17 using an adhesive or a pressure-sensitive adhesive, the present invention is not limited to this, and may be bonded based on an ultrasonic bonding method.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The configuration, structure, and pressure forming method conditions, the shape and dimensions of the molded product, and the like of the pressure forming mold in the examples are examples, and can be changed as appropriate.

DESCRIPTION OF SYMBOLS 10 ... Molded article, 11 ... Bottom face of molded article, 12 ... Side surface of molded article, 13 ... Window part of molded article, 14 ... Printed part, 15, 17 ... Base 16 ... Boss, 18 ... Recess, 19 ... Notch, 21 ... Pressure forming material, 22 ... Pin fixing hole, 30 ... Pressure forming mold, 31 .. Second hydraulic cylinder, 32, 34 ... Oil, 33 ... Third hydraulic cylinder, 41 ... Upper mold, 42 ... Upper mold protrusion, 43 ... Introduction hole, 45 ...・ Fitting part 46... Upper mold movable core part 46 A... Side surface of upper mold movable core part 47 .. Bottom face of upper mold movable core part 48... Projection part 51. Lower mold, 52... Lower mold protrusion, 53... Empty portion, 53 A. Side surface of the void portion, 54... Lower mold movable core storage portion, 55.・ ・Type movable core section, 57 the top surface of the ... lower mold movable core section, 60 ... release promoter layer

Claims (13)

An upper mold protrusion that protrudes toward the lower side is provided on the outer periphery, and an upper mold having an introduction hole for introducing compressed gas, and
A lower mold provided with a lower mold projecting portion on the outer peripheral portion facing the upper mold projecting portion and projecting upward.
A pressure forming mold in which the upper mold protrusion and the lower mold protrusion are in contact with each other via a pressure forming material during mold clamping,
The upper mold is equipped with an upper mold movable core that moves up and down,
The lower mold is equipped with a lower mold movable core that moves up and down,
Pneumatic forming characterized in that a ring-shaped projection similar to the outer edge of the lower mold movable core is provided on the bottom of the upper mold movable core facing the top surface of the lower mold movable core Mold. The lower mold is provided with a lower mold movable core section storage section and a void section communicating with the lower mold movable core section storage section.
When the lower mold movable core part is lowered to the lowest position, the lower mold movable core part is stored in the lower mold movable core part storage unit,
2. The compressed air molding die according to claim 1, wherein when the upper mold movable core portion is lowered to the lowest position, the side surface of the upper mold movable core portion faces the side surface of the void portion.   When the compressed air molding material is sandwiched between the upper mold movable core section and the lower mold movable core section, the space between the bottom surface of the upper mold movable core section and the portion of the compressed air molding material located on the top surface of the lower mold movable core section The pressure-forming mold according to claim 1, wherein a gap exists in the mold.   The die for pressure forming according to any one of claims 1 to 3, wherein a peeling promoting layer is formed on a top surface of the lower mold movable core portion.   The exfoliation promoting layer is composed of a group consisting of a SiC layer, a TiC layer, a TiN layer, a CrN layer, a DLC layer, a TiAlN layer, a TiSin layer, an AlCrN layer, a CrSiN layer, a TiBN layer, an AlCrSiN layer, an AlZrNN layer, an AlZrSiN layer, and a CrBN layer. 5. The compressed air molding die according to claim 4, comprising at least one selected layer.   6. The pneumatic molding according to claim 1, wherein at least a part of a top surface of the lower mold movable core portion in contact with the pneumatic molding material is subjected to a mat treatment. Mold. An upper mold protrusion that protrudes toward the lower side is provided on the outer periphery, and an upper mold having an introduction hole for introducing compressed gas, and
A lower mold provided with a lower mold projecting portion on the outer peripheral portion facing the upper mold projecting portion and projecting upward.
Consisting of
The upper mold is equipped with an upper mold movable core that moves up and down,
The lower mold is equipped with a lower mold movable core that moves up and down,
Use a pressure molding die that has a ring-shaped protrusion similar to the outer edge of the lower mold core on the bottom of the upper mold core that faces the top surface of the lower mold core. A compressed air forming method,
The upper mold movable core part is arranged on the upper side, the lower mold movable core part is arranged on the lower side, the pressure molding material is arranged on the lower mold projection, and the pressure molding material is heated.
After the upper mold and the lower mold are clamped and the upper mold protrusion and the lower mold protrusion are in contact with each other via the heated pressure forming material,
Lowering the upper mold movable core part, raising the lower mold movable core part, sandwiching the compressed air molding material between the upper mold movable core part and the lower mold movable core part, and then the compressed air molding material to the upper mold movable core part and While sandwiched between the lower mold movable core part, lower the upper mold movable core part and the lower mold movable core part to the lowest position,
Introduce compressed gas from the introduction hole to shape the material for compressed air molding,
A compressed air forming method comprising the steps. In the mold for pressure forming,
The lower mold is provided with a lower mold movable core section storage section and a void section communicating with the lower mold movable core section storage section.
When the lower mold movable core part is lowered to the lowest position, the lower mold movable core part is stored in the lower mold movable core part storage unit,
When the upper mold movable core portion is lowered to the lowest position, the side surface of the upper mold movable core portion and the side surface of the void portion face each other,
In the step of forming the compressed air molding material by introducing compressed gas from the introduction hole, the compressed air molding material portion positioned between the side surface of the upper mold movable core portion and the side surface of the cavity portion, Compressed gas is introduced between the side surface of the mold movable core part, so that the portion of the compressed air molding material located between the side surface of the upper mold movable core part and the side surface of the cavity part is the cavity part. The compressed air forming method according to claim 7, wherein the method is pressed against a side surface.   The compressed air molding method according to claim 8, wherein the compressed air molding material has a polycarbonate resin layer.   The compressed air molding method according to claim 9, wherein the compressed air molding material has a laminated structure of an acrylic resin layer and a polycarbonate resin layer.   The compressed air molding method according to claim 9 or 10, wherein printing is performed on at least a part of the outer surface of the polycarbonate resin layer.   The compressed air molding method according to any one of claims 9 to 11, wherein the polycarbonate resin layer is in contact with the upper movable core portion.   The pressure forming material is formed by co-extrusion of an acrylic resin layer having a thickness of 50 μm to 120 μm on one surface of a polycarbonate resin layer, and has a total thickness of 0.5 mm to 1.5 mm. The pressure forming method according to any one of claims 9 to 11, wherein the resin layer has a pencil hardness of 2H or more.

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