JPH0596568A - Manufacture of coated molding - Google Patents

Abstract

PURPOSE:To provide the manufacture of a coated molding having an excellent appearance and performance by coating the surface of a molded form having the surface shape of a molded form having a complicated surface shape such as deep drawing with a film having a uniform film thickness. CONSTITUTION:A sheet 3 for coating is heated by a heating means 4, in which a heat-transfer adjusting member 43a having low thermal conductivity is bonded partially on the surface of a heating member 41. Compressed air is ejected from the ventilating hole 42 of the heating member 41, and a sheet 3 for coating is positioned along the inside of the recessed section 111 of a female mold 11. A mold is closed, and a resin for molding a main body is injection-molded into a cavity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention applies a uniform film thickness to the surface of molded articles such as vehicle bodies of automobiles and motorcycles, housings of office automation equipment and home appliances, stationery and the like. , Give surface decoration, improve surface hardness, weather resistance,
The present invention relates to a method for producing a coated molded product used in a field that needs to be imparted with a function such as soft touch property.

[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 onto the surface of the molded article at the same time as injection molding and various characteristics have been developed. For example, a method of attaching the provided thermoplastic resin sheet is performed.

As a specific example thereof, for example, Japanese Patent Laid-Open No. 59-
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 and supplied to an injection molding die so that the sheet faces the injection molding female die. Hold and then heat the part of the sheet that is held facing the female mold between the heating member and the female mold, and make the sheet adhere to the surface of the mold (pre-molding) by vacuum / pressure molding (injection molding). A device for performing is proposed.

[0004]

Problems to be Solved by the Invention JP-A-59-2028
According to the method disclosed in Japanese Patent Publication No. 30, it is possible to transfer the pattern printed on the sheet to the surface of the deep-drawn molded product or to attach the thermoplastic resin sheet. However, when the sheet is run along 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 is locally extremely thin and the appearance of the obtained molded product is However, there is a problem in that the durability may be deteriorated and the durability may be deteriorated.

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

[0006]

In the method for manufacturing a coated molded article according to the present invention, a cavity having an inner surface shape corresponding to the outer surface shape of the molded article to be molded is provided between the female mold and the male mold. In a method for producing a coated molded article by supplying a coating sheet and a main body molding resin into a mold, when introducing the coating sheet into the cavity, the surface of the heating member provided with a vent hole A positioning mark is drawn, and the coating sheet is heated by a heating means which is freely breathable and has a thermal conductivity different from the surface material of the heating member and which is capable of being attached to any position. This is a method in which compressed air is jetted from the ventilation hole of the heating member to cause the covering sheet to follow the inside of the cavity, and thereafter molding with the resin for molding the main body is performed in the cavity.

In the present invention, the sheet is preferably composed of a film which is malleable at least under heating, and for example, a thermoplastic resin sheet, a thermosetting resin sheet, a photocurable resin sheet, An electron beam curable resin sheet, a thermosetting resin sheet, a photocurable resin sheet, or an electron beam curable resin sheet is laminated with a colored resin layer containing a high pigment.
Colored, multi-colored sheets such as three colors, a laminated sheet in which a sheet other than the above thermoplastic resin sheet is laminated on a thermoplastic resin sheet, and printing is performed on the surface or interface (between laminated sheets) of these sheets. A laminated sheet or the like is used.

As the thermoplastic resin sheet, for example,
Polystyrene, acrylic polymer, polycarbonate, polyvinyl chloride, polyethylene, polypropylene,
Acrylonitrile-butadiene-styrene copolymer (A
BS), modified polyphenylene oxide, polyphenylene sulfide, polyether imide, polyether ether ketone, ionomer and the like as a main component are used.

As the 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 an oligomer, a thermoplastic resin and / or a resin having a vinyl group, and a peroxide An uncured or semi-cured sheet or the like containing a material as a main component is used.

Examples of the photocurable resin sheet include:
An uncured or semi-cured sheet containing a thermoplastic resin, a monomer having a double bond such as a vinyl group, and a photoinitiator as main components is used.

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

As the molding resin used in the present invention, a thermoplastic resin for the synthetic resin sheet, an unsaturated polyester resin, an acrylic resin, an epoxy resin, or a filler such as glass fiber is added to these resins. The thing etc. are mentioned.

The heat transfer adjusting member used in the present invention having air permeability and high heat conductivity has, for example, a heat conductivity of 10 or less.
^{-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 material, specifically, a plate made of a metal such as silver, copper, or aluminum and having a vent hole formed by machining or the like. If necessary, this member is subjected to surface treatment such as rust prevention and release.

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

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

The coated molded article preferably produced in the present invention includes, for example, vehicle bodies such as automobiles and motorcycles, housings such as office automation equipment and home appliances, molded articles such as stationery, and the like. And the like to impart surface decoration, or to impart functions such as surface hardness, weather resistance improvement, and soft touch property.

[0017]

In 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 hole, and the positioning mark is provided on the surface of the heating member, which has the air permeability and the thermal conductivity. The coating sheet is heated by the heating means in which a heat transfer adjusting member different from the surface material of the heating member is attached at an arbitrary position, and the coating sheet is spread along the inside of the cavity by ejecting compressed air from the ventilation hole of the heating member. By heating the covering sheet corresponding to a portion where the covering sheet is greatly stretched and the film thickness may be too thin, the surface of the heating member has air permeability and thermal conductivity. Since the heat transfer control member made of a smaller material is partially attached with the positioning mark as a guide, the amount of heat transfer can be made smaller than that of other parts, so that part It can be adjusted so that the film thickness is stretched hear is not thin.

On the contrary, the heating of the coating sheet corresponding to the portion where the coating sheet is difficult to be stretched and the film thickness may be too thick is performed. The surface of the heating member has air permeability and the thermal conductivity is the surface of the heating member. Since the heat transfer control member made of a material larger than the material is partially attached with the positioning mark as a guide, the heat transfer amount can be made larger than that of other parts, so that part is not stretched. It can be adjusted so that the film thickness does not become thick.

As a result, the surface of the molded product is coated with a film having a uniform film thickness to give surface decoration excellent in appearance and performance, and to impart functions of surface hardness, weather resistance and soft touch property. can do.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments of the drawings. First, an example of a mold used in the present invention is shown in FIG.
Will be described.

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

That is, a recess 111 which forms the outer surface of the molded product is provided in the female mold 11, and the recess 111 is further provided with a hemispherical recess 111a. Also, male 1
A convex portion 12 forming the inner surface of a horizontally long box-shaped molded article is provided in
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 die 1 is closed, the concave portion 111 of the female die 11, the convex portion 121 of the male die 12 and the end face forming portion 1 are formed.
Cavity 13 where the part surrounded by 22 is for molding the molded product
It is said that.

The concave portion 111 of the female die 11 is provided with a large number of extremely small vent holes 112 so that air can be sucked and ejected through the vent holes 112.
When the mold 1 is opened, the 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 movable back and forth. The heating means 4 includes a heating member 41. The heating element 41 has a number of very small vent holes 42.
Is provided so that suction and ejection of air can be performed through the vent hole 42. The surface of the heating member 41 is treated with a fluororesin, and a grid-like scale having a grid width of 10 mm is drawn on the surface. Further, a heat transfer adjusting member 43 having air permeability and a thermal conductivity different from that of the surface member of the heating member can be attached at any position by using a grid-like scale as a guide. To fix the heat transfer adjusting member 43 to the surface of the heating member 41, an adhesive agent such as a heat-resistant silicone adhesive is used, or magnetic force or other mechanical means is appropriately adopted.

Next, FIG. 2 sequentially showing an example of the process of the present invention.
~ It demonstrates with reference to FIG. First, as shown in FIG. 2, the hollow portion 111a is formed substantially at the center of the surface of the heating member 41 of the heating means 4 on which a large number of vent holes 42 are formed, which corresponds to the hemispherical hollow portion 111a of the female die 11. A heat transfer adjusting member 43a having air permeability and low thermal conductivity, which is formed by stacking circular gauze having a thickness of about half the diameter of 3 mm and having a thickness of 3 mm, is adhered by a silicone adhesive.

On the side surface where the concave portion 111 of the female die 11 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 bonded. Then, the suction of the ventilation hole 42 is stopped.

Next, as shown in FIG. 3, the recess 1 of the female mold 11 is formed.
Vacuum suction is performed through the ventilation holes 112 of the heating member 41, and compressed air is ejected through the ventilation holes 42 of the heating member 41 to bring the covering sheet 3 into close contact with the entire surface of the recess 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 recessed portion 111a of the concave portion 111 of the female mold 11, the covering sheet 3 thereon. Heat conduction from the heating member 41 is less than that of the other portion, and only that portion is stretched so that the entire film thickness is uniform without being greatly stretched so that the film thickness is reduced. 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 vent hole 42 of the female die 11 and the ejection of the compressed air from the vent hole of the heating member 41 are stopped, the heating means 4 is removed, and the die 1 is removed as shown in FIG. close. In the mold 1, a closed cavity 13 surrounded by the concave portion 111 of the female mold 11 and the convex portion 121 of the male mold 12 and the end face forming portion 122 in which the covering sheet 3 is in close contact with the entire surface is formed. It is formed.

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

Next, another example of the process of the present invention will be described with reference to FIG. 6, FIG. 7 and FIG. First, FIG.
As shown in FIG. 5, the heating member 41 of the heating means 4 corresponds to a rectangular portion of the surface of the female die 11 on which a large number of vent holes 42 are formed and which faces the female die 11 side, where the hemispherical recess 111a is not provided. A rectangular shape with a vertical and horizontal length of about half is approximately half the length of the rectangular part, and a diameter of 0.5 mm with a thickness of 3 mm.
A heat conduction adjusting member 43b having a high heat conductivity, which is made of an aluminum plate and is provided with ventilation holes of about m at a rate of about 10 / cm ² , is adhered by a silicone adhesive.

On the side surface where the concave portion 111 of the female die 11 opens,
In the state in which the covering sheet 3 is suction-fixed through the ventilation holes 42 on the surface to which the numerous ventilation holes 42 of the heating member 41 of the heating means 4 are opened and the heat transfer adjusting member 43b having high thermal conductivity is adhered, Supply with 4. Then the vent 42
Stop sucking.

Next, as shown in FIG. 7, the concave portion 1 of the female mold 11 is formed.
Vacuum suction is performed through the ventilation holes 112 of the heating member 41, and compressed air is ejected through the ventilation holes 42 of the heating member 41 to bring the covering sheet 3 into close contact with the entire surface of the recess 111. At this time, since the heat transfer adjusting member 43b having air permeability and high thermal conductivity is adhered to the surface of the heating member 41 corresponding to the rectangular portion other than the recessed portion 111a of the concave portion 111 of the female mold 11, The upper cover sheet 3 has more heat conduction from the heating member 41 than the other parts, and only that part 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, the melted main body molding resin for main body molding is injection molded into the cavity 13 from the injection molding machine through the sprue 123. Then, after a lapse of a predetermined time, after cooling in the mold 1, the mold 1 is opened, the molded product is taken out, the sheet protruding from the end face of the molded product is cut, and as shown in FIG. A coated molded product 2 having a hemispherical projection on a part of a horizontally long box-shaped surface of which the outer surface of 21 is coated with a coating 22 having a uniform film thickness is obtained.

Example 1 Using the mold 1 shown in FIG. 1 and following the steps shown in FIGS. 2 to 4 under the following conditions, the coated molded article 2 as shown in FIG.
Was molded.

As the sheet, a sheet of acrylonitrile-butadiene-styrene copolymer (ABS) having a film thickness of 500 μm prepared by calendering was used, the temperature of the heating means 41 was set to 160 ° C., and the ventilation hole 112 of the female mold 11 was used. 3 kg / cm from the ventilation hole 42 of the heating means 41 during vacuum suction
Air was blown at ² for 10 seconds.

ABS (manufactured by Denki Kagaku Kogyo Co., Ltd .: trade name "ABS-ME") was used as the resin for molding the main body, and the nozzle tip temperature 230 was set in the cavity 13 in which the temperature of the female mold 11 was 70 ° C. from the injection molding machine. The resin for molding the main body melted at ℃ was injected.

As a result, a coated molded product 2 having a hemispherical projection on a part of a horizontally long box-shaped surface in which the outer surface of the ABS molded product main body 21 is coated with a coating 22 of an ABS sheet.
I was able to get The coating film of the coated molded product 2 had a uniform film thickness and had a good appearance.

Example 2 A coated molded article 2 as shown in FIG. 5 was prepared 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, the outer surface of the molded body 21 made of ABS is covered with the coating 22 of the ABS sheet, and the coated molded article 2 has a hemispherical projection on a part of the oblong box-shaped surface.
I was able to get The coating film of the coated molded product 2 had a uniform film thickness and had a good appearance.

Comparative Example 1 As in Example 1 except that the heating of the coating sheet was carried out by a heating member which was permeable to the surface of the heating member 41 and did not adhere to the heat transfer adjusting member 43a having a low thermal conductivity. A coated molded product was manufactured in the same manner.

As a result, the coating film coated 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 a poor appearance is obtained. I couldn't.

[0042]

[Effect] In the present invention, because of the above-mentioned constitution, the surface of the molded product is coated with a film having a uniform thickness,
It is possible to impart surface decoration excellent in appearance and performance, and impart functions such as surface hardness, weather resistance improvement, and soft touch property.

[Brief description of drawings]

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

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

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

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

FIG. 5 is a vertical cross-sectional perspective view showing an example of a coated molded article obtained by the present invention.

FIG. 6 illustrates a female mold 11 for explaining another example of the process of the present invention.
FIG. 5 is a vertical cross-sectional end view showing a state in which the covering sheet 3 is supplied to the side surface of the sheet together with the heating means 4.

FIG. 7 shows a female mold 11 for explaining another example of the process of the present invention.
FIG. 6 is a vertical cross-sectional end view showing a state in which the covering sheet 3 is brought into close contact with the recess 111 of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold 2 Coated molded product 3 Coating sheet 4 Heating means 11 Female mold 12 Male mold 13 Cavity 21 Molded product main body 22 Coating 41 Heating member 42 Vent hole 43 Heat transfer adjusting member 43a Heat transfer adjusting member with low thermal conductivity 43b High heat Conductivity heat transfer adjusting member 111 Recessed portion 111a Recessed portion 112 Vent hole 121 Convex portion 121a Projected portion 122 End face forming portion

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B29C 51/42 7421-4F B29K 55:02

Claims (1)

[Claims] 1. A coating sheet and a resin for molding a main body are provided in a mold provided with a cavity having an inner surface shape corresponding to an outer surface shape of a molded product to be molded between a female mold and a male mold. In the method for producing a coated molded article by supplying, when introducing the coating sheet into the cavity, a positioning mark is drawn on the surface of the heating member provided with a ventilation hole, and there is air permeability on it. The coating sheet is heated by the heating means which has a heat conductivity different from that of the surface material of the heating member and can be attached at any position, and compressed air is jetted from the ventilation hole of the heating member to the coating sheet. Thus, the method for producing a coated molded article is characterized in that the resin is molded along the inside of the cavity, and thereafter the resin for molding the main body is molded in the cavity.