JP3048443B2 - Manufacturing method of coated molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molded article such as a vehicle body such as an automobile or a motorcycle, a housing such as an OA device or a home electric appliance, a stationery or the like, which is coated with a film having a uniform thickness on the surface of the molded article. , Surface decoration, surface hardness, weather resistance improvement,
The present invention relates to a method for producing a coated molded product used in a field where it is necessary to impart functions such as soft touch properties.

[0002]

2. Description of the Related Art In recent years, as a method for increasing the added value of plastic molded articles such as daily necessities and automobile interiors, a method of transferring a pattern printed on a sheet to a surface of the molded article at the same time as injection molding, and various characteristics have been proposed. A method of attaching a provided thermoplastic resin sheet or the like has been performed.

As a specific example, see, for example,
As described in JP-A-202830, a continuous sheet on which a pattern is printed is sandwiched between a heating member having a ventilation hole and a frame member, supplied to an injection molding die, and the sheet is opposed to a female mold for injection molding. Holding, and then heating the portion of the sheet which is held opposite the female mold between the heating member and the female mold, and injecting (pre-molding) the sheet into the mold surface by vacuum / pressure molding to perform injection molding. Has been proposed.

[0004]

Problems to be Solved by the Invention JP-A-59-2028
According to the method disclosed in Japanese Patent No. 30, it is possible to transfer a pattern printed on a sheet to the surface of a deep-drawn molded product, or to attach a thermoplastic resin sheet. However, when the sheet is made to conform to the inside of the female mold, the sheet is greatly stretched at the corners of the mold and the like, so that the film thickness of the sheet partially becomes extremely thin, and the appearance of the obtained molded product is reduced. However, there is a problem that the durability may deteriorate and a problem may occur in durability.

The present invention solves the above-mentioned conventional problems and provides a coating having a uniform film thickness on the surface of a molded article having a complicated surface shape such as deep drawing, and has excellent appearance and performance. The purpose of the present invention is to provide a method for producing a coated molded article.

[0006]

According to the present invention, there is provided a method for producing a coated molded article, wherein a cavity having an inner surface shape corresponding to an outer surface shape of a molded product to be molded is provided between a female mold and a male mold. In a method for manufacturing a coated molded product by supplying a coated sheet and a resin for molding a main body into a mold, when the coating sheet is introduced into a cavity, a surface of a heating member provided with a vent hole is formed. A mark for positioning is drawn, and the covering sheet is heated by a heating means on which a heat transfer adjusting member having air permeability and heat conductivity different from the surface material of the heating member can be freely attached at any position, This is a method in which the covering sheet is made to flow along the inside of the cavity by blowing out compressed air from the ventilation holes of the heating member, and then molded with the resin for molding the main body inside the cavity.

In the present invention, it is preferable that the sheet is formed of a film having ductility at least under heating. For example, a sheet made of a thermoplastic resin, a sheet made of a thermosetting resin, a sheet made of a photocurable resin, A sheet made of an electron beam-curable resin, a sheet made of a thermosetting resin, a sheet made of a photocurable resin, a sheet made of an electron beam-curable resin, and a laminated sheet obtained by laminating a colored resin layer containing a high pigment,
Multi-colored sheets such as three-colored sheets, laminated sheets obtained by laminating sheets other than the above-mentioned thermoplastic resin sheets on a thermoplastic resin sheet, and printing on the surface or interface (between the laminated sheets) of these sheets. A laminated sheet or the like is used.

As a sheet made of a thermoplastic resin, for example,
Polystyrene, acrylic polymer, polycarbonate, polyvinyl chloride, polyethylene, polypropylene,
Acrylonitrile butadiene styrene copolymer (A
BS), a modified polyphenylene oxide, a polyphenylene sulfide, a polyetherimide, a polyetheretherketone, a sheet mainly composed of an ionomer and the like are used.

As a thermosetting resin sheet, for example,
An uncured or semi-cured sheet mainly composed of a reactive acrylic resin such as an acrylic polyol and a blocked isocyanate, a reactive vinyl monomer and / or oligomer, a thermoplastic resin and / or a resin having a vinyl group, and peroxide An uncured or semi-cured sheet mainly composed of a material and the like is used.

As a photo-curable resin sheet, for example,
An uncured or semi-cured sheet mainly containing a thermoplastic resin, a monomer having a double bond such as a vinyl group, and a photoinitiator is used.

As the electron beam-curable resin sheet, for example, an uncured or semi-cured sheet mainly containing a thermoplastic resin and a monomer having a double bond such as a vinyl group is used.

As the molding resin used in the present invention, the above-mentioned thermoplastic resin for synthetic resin sheets, unsaturated polyester resin, acrylic resin, epoxy resin, or a filler such as glass fiber added to these resins. And the like.

As the heat-transfer adjusting member having air permeability and high thermal conductivity used in the present invention, for example, a heat conductive member having a thermal conductivity of 10
^{-1 ~10 0 (cal / s ·} cm · ℃) about, a heat-resistant (not melting or greatly deformed at a temperature of the heating means)
Examples thereof include a plate made of a metal, such as silver, copper, or aluminum, which is provided with a vent hole by machining or the like. This member is subjected to a surface treatment such as rust prevention and release as required.

The heat-transfer adjusting member having air permeability and low thermal conductivity used in the present invention has, for example, a heat conductivity of 10%.
Heat resistance of about ^-2 to 10 ^-6 (cal / s · cm · ° C) (does not melt or deform significantly at the temperature of the heating means)
Materials, woven or non-woven fabrics made of fibers such as silk, cotton, etc. or glass fibers, foams of polymer materials such as cross-linked polyethylene having open cells, silica, alumina, those made of porous inorganic materials such as zeolite, A plate made of a material such as wood or paper, or a material such as a fluororesin or an engineering plastic resin, which is provided with a vent hole by machining or the like may be used.

The method for producing a coated molded article of the present invention is not limited to injection molding, stamping molding, and sheet molding compound (SMC) press molding, as long as it is a method of supplying resin to a mold and molding. Such a method may be used. Further, the material of the mold and the position of the gate for injection molding used here may be a known material or a known method.

Examples of the coated molded article preferably produced in the present invention include, for example, a molded article such as a vehicle body such as an automobile or a motorcycle, a housing such as OA equipment or a household electric appliance, a stationery, etc. To impart surface decoration, or to impart functions such as surface hardness, improvement in weather resistance, and soft touch properties.

[0017]

According to the present invention, when the covering sheet is introduced into the cavity, a positioning mark is drawn on the surface of the heating member provided with the ventilation holes, on which the air-permeable and heat-conductive material is placed. The covering sheet is heated by a heating means in which a heat transfer adjusting member different from the surface material of the heating member is attached to an arbitrary position, and the covering sheet is formed along the inside of the cavity by ejecting compressed air from the ventilation holes of the heating member. The heating of the coating sheet corresponding to the portion where the coating sheet may be greatly stretched and the film thickness may become too thin by applying the heat to the surface of the heating member has air permeability and thermal conductivity. By the heating means in which the heat transfer adjusting member made of a smaller material is partially attached with the positioning mark as a guide, the heat transfer can be performed with a smaller heat transfer amount than the other portions, so that the portion is It can be adjusted so that the film thickness is stretched hear is not thin.

Conversely, the heating of the coating sheet corresponding to the portion where the coating sheet is unlikely to be stretched and the film thickness may be too large is performed by heating the surface of the heating member with air permeability and heat conductivity of the surface of the heating member. The heat transfer adjusting member made of a material larger than the material is heated by partially attaching the heat transfer adjusting member with the positioning mark as a guide, so that the heat transfer amount can be made larger than the other portions, so that the portion is not stretched. Can be adjusted so that the film thickness does not become too thick.

Thus, the surface of the molded article is coated with a film having a uniform thickness to give a surface decoration with excellent appearance and performance, and to impart functions of improving surface hardness, weather resistance and soft touch properties. can do.

[0020]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. First, an example of a mold used in the present invention is shown in FIG.
This will be described with reference to FIG.

Reference numeral 1 denotes an injection molding die used in the present invention, which comprises a female die 11 on the moving side and a male die 12 on the fixed side.
Between the female mold 11 and the male mold 12, an inner surface shape corresponding to the outer shape of a molded product to be molded having a hemispherical protrusion on a part of a horizontally long box-like surface having a substantially U-shaped cross section is provided. Cavity 1
3 are provided.

That is, the female mold 11 is provided with a concave portion 111 forming the outer surface of the molded product, and the concave portion 111 is further provided with a hemispherical concave portion 111a. In addition, male type 1
2, a convex portion 12 forming an inner surface of a horizontally long box-shaped molded product is provided.
1 and an end face forming part 122 forming an end face are provided,
The protrusion 121 is further provided with a hemispherical protrusion 121a.

When the mold 1 is closed, the concave portion 111 of the female mold 11, the convex portion 121 of the male mold 12, and the end face forming portion 1
22 is a cavity 13 for molding a molded product.
It is said.

The concave portion 111 of the female mold 11 is provided with a large number of extremely small ventilation holes 112, through which air can be sucked and ejected.
When the mold 1 is opened, a heating means 4 shown in FIGS. 2 and 3 is provided between the female mold 11 and the male mold 12 so as to be able to advance and retreat. The heating means 4 includes a heating member 41. The heating member 41 has a number of very small vents 42
Is provided, and suction and ejection of air can be performed through the ventilation hole 42. The surface of the heating member 41 is subjected to a fluororesin treatment, and a grid-like scale with a grid width of 10 mm is drawn thereon. A heat-transfer adjusting member 43 having air permeability and different in heat conductivity from the surface material of the heating member can be freely attached to an arbitrary position by using a grid-like scale as a guide. For fixing the heat transfer adjusting member 43 to the surface of the heating member 41, an adhesive such as a heat-resistant silicone adhesive or the like, magnetic force or other mechanical means is appropriately adopted.

Next, FIG. 2 sequentially shows an example of the process of the present invention.
This will be described with reference to FIGS. First, as shown in FIG. 2, a depression 111a is provided substantially at the center of a portion corresponding to the hemispherical depression 111a of the female mold 11 on the surface of the heating member 41 of the heating means 4 where the many ventilation holes 42 are opened. The air-permeable and low-thermal-conductivity heat-transfer adjusting member 43a on which a circular gauze having a thickness of about 3 mm and having a diameter approximately half of the diameter of the heat-transferring member is laminated is bonded with a silicone adhesive.

On the side of the female mold 11 where the recess 111 opens,
The covering sheet 3 is supplied together with the heating means 4 in a state in which a large number of ventilation holes 42 of the heating member 41 of the heating means 4 are opened and suction-fixed through the ventilation holes 42 on the surface to which the heat transfer adjusting member 43a is adhered. Thereafter, the suction of the ventilation holes 42 is stopped.

Next, as shown in FIG.
In addition to vacuum suction through the ventilation holes 112 of 11, compressed air is blown out through the ventilation holes 42 of the heating member 41, and the covering sheet 3 is brought into close contact with the entire surface of the concave portion 111. At this time, since the heat-transfer adjusting member 43a having air permeability and low thermal conductivity is adhered to the surface of the heating member 41 corresponding to the concave portion 111a of the concave portion 111 of the female mold 11, the covering sheet 3 thereon is formed. The portion has less heat conduction from the heating member 41 than the other portions, and only the portion is stretched so that the entire film thickness becomes uniform without being greatly stretched so as to reduce the film thickness, and is used for coating. The sheet 3 is brought into close contact with the entire concave portion 111 of the female mold 11.

Thereafter, the suction of the air from the air holes 42 of the female mold 11 and the ejection of the compressed air from the air holes of the heating member 41 are stopped, the heating means 4 is removed, and as shown in FIG. close. In the mold 1, a closed cavity 13 surrounded by the concave portion 111 of the female mold 11, the convex portion 121 of the male mold 12, and the end face forming portion 122 in a state where the covering sheet 3 is in close contact with the entire surface. It is formed.

In the cavity 13, a molten resin for molding the main body for molding the main body by the injection molding machine is sprue 12.
Injection molding through 3. After elapse of a predetermined time and cooling in the mold 1, the mold 1 is opened, the molded product is taken out, and the sheet protruding from the end face of the molded product is cut, and as shown in FIG. A coated molded article 2 having hemispherical projections on a part of a horizontally long box-shaped surface in which the outer surface of 21 is covered with a film 22 having a uniform thickness is obtained.

Next, another example of the process of the present invention will be described with reference to FIGS. First, FIG.
As shown in the figure, the surface of the heating member 41 of the heating means 4 facing the female mold 11 side where a large number of ventilation holes 42 are opened corresponds to a rectangular portion where the hemispherical recess 111a of the female mold 11 is not provided. In the approximate center of the part to be formed, the rectangular part is about half the length and width of the rectangle, and the diameter of 3 mm thick is 0.5 m.
A heat conduction adjusting member 43b having a high thermal conductivity and made of an aluminum plate having about 10 m / cm ² ventilation holes is bonded with a silicone adhesive.

On the side of the female mold 11 where the recess 111 opens,
In a state in which the coating sheet 3 is suction-fixed through the ventilation holes 42 on the surface where the large number of ventilation holes 42 of the heating member 41 of the heating unit 4 are opened and the heat transfer adjusting member 43b having high thermal conductivity is adhered, the heating unit Supply with 4. Then, the vent 42
Stop suction.

Next, as shown in FIG.
In addition to vacuum suction through the ventilation holes 112 of 11, compressed air is blown out through the ventilation holes 42 of the heating member 41, and the covering sheet 3 is brought into close contact with the entire surface of the concave portion 111. At this time, since the heat-transfer adjusting member 43b having air permeability and high thermal conductivity is bonded to the surface of the heating member 41 corresponding to the rectangular portion other than the concave portion 111a of the concave portion 111 of the female mold 11, The upper portion of the cover sheet 3 has more heat conduction from the heating member 41 than the other portions, and only that portion is stretched so that the entire film thickness becomes uniform without increasing the film thickness. The sheet 3 is brought into close contact with the entire concave portion 111 of the female mold 11.

Thereafter, a molten main body molding resin for main body molding is injection-molded into the cavity 13 through a sprue 123 by an injection molding machine. After elapse of a predetermined time and cooling in the mold 1, the mold 1 is opened, the molded product is taken out, and the sheet protruding from the end face of the molded product is cut, and as shown in FIG. A coated molded article 2 having hemispherical projections on a part of a horizontally long box-shaped surface in which the outer surface of 21 is covered with a film 22 having a uniform thickness is obtained.

Example 1 Using a mold 1 shown in FIG. 1, a coated molded article 2 as shown in FIG.
Was formed.

As the sheet, a sheet made of an acrylonitrile-butadiene-styrene copolymer (ABS) having a thickness of 500 μm and formed by calendering is used. The temperature of the heating means 41 is set to 160 ° C. 3 kg / cm from the air hole 42 of the heating means 41 during vacuum suction
Air was spouted at ² for 10 seconds.

As the resin for molding the main body, ABS (manufactured by Denki Kagaku Kogyo Co., Ltd .: trade name "ABS @ ME") is used. The resin for molding the main body, which was melted at ℃, was injected.

As a result, the coated molded article 2 having a hemispherical projection on a part of the oblong box-shaped surface in which the outer surface of the molded article body 21 made of ABS is coated with the coating 22 made of ABS sheet
Could be obtained. The film thickness of the coated molded article 2 was uniform, and the appearance was good.

Example 2 A coated molded product 2 as shown in FIG. 5 was used in the same manner as in Example 1 except that the mold 1 shown in FIG. 1 was used and the above steps shown in FIGS. 6, 7 and 4 were followed. Was manufactured.

As a result, a coated molded article 2 having a hemispherical projection on a part of a horizontally long box-shaped surface in which the outer surface of the molded article body 21 made of ABS is coated with a coating 22 made of ABS sheet.
Could be obtained. The film thickness of the coated molded article 2 was uniform, and the appearance was good.

[0040] The heating of the Comparative Example 1 coating sheet, except that the heat transfer adjusting member 43a of and low thermal conductivity breathable the surface of the heating member 41 was performed by heating member does not adhere, as in Example 1 In the same manner, a coated molded product was manufactured.

As a result, the thickness of the coating on the surface of the hemispherical projections on the outer surface of the ABS molded article body is extremely thin, and only a coated molded article having poor appearance can be obtained. Could not.

[0042]

According to the present invention, since the structure is as described above, the surface of the molded article is coated with a film having a uniform thickness.
Surface decoration with excellent appearance and performance can be imparted, and functions such as surface hardness, weather resistance improvement, and soft touch properties can be imparted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a mold used in the present invention.

FIG. 2 is a vertical cross-sectional end view illustrating an example of a process of the present invention, showing a state in which a covering sheet 3 is supplied together with a heating means 4 to a side surface of a female mold 11;

FIG. 3 is a vertical cross-sectional end view illustrating an example of a process of the present invention, showing a state in which a covering sheet 3 is in close contact with a concave portion 111 of a female mold 11;

FIG. 4 is a vertical cross-sectional end view illustrating an example of a process of the present invention and showing a state in which a resin for molding a main body is injection-molded in a cavity.

FIG. 5 is a longitudinal sectional perspective view showing an example of a coated molded product obtained by the present invention.

FIG. 6 illustrates a female mold 11 for explaining another example of the process of the present invention.
FIG. 4 is a longitudinal sectional end view showing a state in which a coating sheet 3 is supplied together with a heating means 4 to the side surface of FIG.

FIG. 7 illustrates a female mold 11 for explaining another example of the process of the present invention.
FIG. 4 is a longitudinal sectional end view showing a state in which the covering sheet 3 is in close contact with a concave portion 111 of FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 mold 2 coated molded article 3 covering sheet 4 heating means 11 female mold 12 male mold 13 cavity 21 molded article main body 22 coating 41 heating member 42 ventilation hole 43 heat transfer adjusting member 43a heat transfer adjusting member with low thermal conductivity 43b high heat Heat transfer adjusting member for conductivity 111 Depressed portion 111a Depressed portion 112 Vent hole 121 Convex portion 121a Projection portion 122 End face forming portion

Continuation of the front page (56) References JP-A-3-34828 (JP, A) JP-A-59-202830 (JP, A) JP-A-62-256620 (JP, A) JP-A-61-137716 (JP, A) JP-A-61-63424 (JP, A) JP-A-60-212314 (JP, A) JP-A-63-162218 (JP, A) JP-A-53-128917 (JP, A) 4-341811 (JP, A) JP-B-63-139717 (JP, B2) JP-B-63-21386 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 45/00 -45/84 B29C 33/00-33/76

Claims (1)

(57) [Claims] 1. A coating sheet and a body molding resin are placed in a mold provided with a cavity having an inner surface shape corresponding to the outer shape of a molded product to be molded between a female mold and a male mold. In the method of supplying and manufacturing a coated molded product, when introducing the coating sheet into the cavity, a positioning mark is drawn on the surface of the heating member provided with the ventilation hole, and there is air permeability on it. The covering sheet is heated by a heating means having a thermal conductivity different from that of the surface material of the heating member, and the compressed sheet is blown out from the ventilation hole of the covering member. A method for producing a coated molded article, wherein the molded article is formed along a cavity, and then molded with a resin for molding a main body in the cavity.