JP2009131969A - Molded article of polycarbonate resin composition and injection molding method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molded article of a polycarbonate resin composition which gives a sense of elegance, has high gloss and a deep color tone but has no weld line and no warp. <P>SOLUTION: The molded article is molded by using a die assembly and has ≤0.2 μm R<SB>z</SB>, ≤25 μm RSm and ≤0.7% reflectance of the light having 400-650 nm wavelength when measured by a spectrophotometer. The die assembly is provided with: (A) a die having a first die part 11, a second die part 12, a molten resin injection part 14 and a cavity 13; and (B) bushings 20A, 20B. The bushing 20A or 20B is composed of (a) a metallic block 31A or 31B, (b) a metallic under layer 32A or 32B having 0.03-1 mm thickness and (c) a melt-sprayed film 33A or 33B which is formed on the metallic under layer 32A or 32B and consists of ceramics. The melt-sprayed film has the porosity varying to the thickness direction thereof so that the porosity becomes smaller as it goes closer to the surface thereof. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molded article made of a polycarbonate resin composition and an injection molding method thereof.

  Painted products are usually applied to molded products such as exterior materials and casings of electronic devices typified by mobile phones, PDAs, portable music players, game machines, personal computers and the like. Since the entire molded product is made thinner and lighter, the thickness of the molded product is designed to be thin. Therefore, in the injection molding of such a molded product, for example, a mold assembly having a multi-point pinpoint gate is used, and the flow distance of the molten thermoplastic resin injected into the cavity is shortened to melt the inside of the cavity. Fully filled with thermoplastic resin. Therefore, a weld line is generated at the joining point in the cavity of the molten thermoplastic resin, and a weld line is also generated in a portion of the molded product provided with holes and openings for releasing heat. In order to cover these weld lines, the surface of the molded product is thickly coated.

  However, it is not preferable to apply the coating from the viewpoint of reducing the manufacturing cost of the molded product. Further, when the thickness of the coating is increased, the surface of the coating becomes cocoon skin, which causes a loss of luxury. Although it is possible to prevent the skin skin and appearance from being damaged by applying a thin transparent coating, the original purpose of covering the weld line cannot be achieved.

  Attempts have been made to reduce the manufacturing cost by eliminating the coating. However, as described above, since a weld line is generated in the molded product, a texture that is not easily noticeable when observed with the naked eye is often formed on the surface of the molded product. However, when the texture is formed, there is a problem that the molded article lacks a high-class feeling. In addition, the molded article often requires high glossiness, and among them, there is a strong demand for black with a high-class feeling and a calm atmosphere, and further with a jet black feeling.

  As a molding material, it is desirable to use a polycarbonate (PC) resin from the viewpoint of moldability, strength, and appearance, but in normal injection molding, appearance defects are likely to occur due to the occurrence of weld lines. In addition, when injection molding is performed using a polycarbonate resin composition to which a pigment used as a colorant (in the case of black, for example, carbon black) is added, the molded product can be colored to a desired color, but there is no deep color tone. As a result, a high-class feeling cannot be obtained.

  Further, in the case of a black molded product having high gloss, there is a problem that even if the molded product has a slight warp, it is visually observed. When the injection molding method is employed, the molded product is often warped, but it is important to reduce the distortion of the molded product in order to suppress the occurrence of warpage.

  One of the factors that cause the above-mentioned molding failure is that the molten thermoplastic resin that contacts the surface of the mold cavity (referred to as the mold cavity surface) is rapidly cooled and solidified. And the cause of the rapid cooling and solidification of such a molten thermoplastic resin originates in the metal mold | die being produced from steel materials.

  For example, Japanese Patent Laid-Open No. 8-318534 discloses a molding having an excellent appearance by using a material with low thermal conductivity for nesting to suppress quenching and solidification of a molten thermoplastic resin injected into a cavity. A method of forming an article has been proposed. Here, the nesting is made of ceramics or glass.

  Japanese Unexamined Patent Publication No. 5-38721 discloses a synthetic resin molding die in which a thin layer made of ceramics or cermet is formed on the cavity surface of the die. This thin layer is formed by a thermal spraying method in which many voids are intentionally generated for the purpose of improving heat insulation. Such a thin layer is hereinafter referred to as a ceramic sprayed layer for convenience. This ceramic sprayed layer may not be dense and is not easily damaged by heat or pressure.

  In Example 5 of Japanese Patent Application Laid-Open No. 2004-175112, there is disclosed a nesting 25 constituted by a nesting body 26 made of stainless steel, a heat insulating layer 27, and a sealing layer 28. The heat insulating layer 27 is formed on the nested body 26 by a plasma powder spraying method using zirconia ceramic material powder. On the other hand, a sealing layer 28 is formed on the surface of the heat insulating layer 27 by Ni-P electroless plating.

JP-A-8-318534 Japanese Patent Laid-Open No. 5-38721 JP 2004-175112 A

By the way, in the technique disclosed in Japanese Patent Application Laid-Open No. 8-318534, the nesting is made of a dense but brittle material. The plate is pressed with a specific clearance, and measures are taken to protect the edge of the nesting that is easily damaged. However, it may be difficult to arrange the metal plate due to the structure of the mold, the shape of the cavity, the molded product, or the like. In addition, since the insert made of a sintered body obtained by a firing method has a dense structure, when lapping is performed, the surface roughness (arithmetic mean height of the contour curve) _Ra is 0.05 μm or less. It is very easy to get. However, since the density of the nesting is high, using the nesting in a portion where tensile stress is applied has a drawback that the nesting is easily damaged.

  As a method of suppressing the cooling of the molten thermoplastic resin in the cavity, a method of disposing a resin material with low thermal conductivity inside the mold has also been proposed. There is a problem that the provided fine unevenness is deformed and the durability is poor. It has also been proposed to prevent the deformation by forming a metal film on the surface of such a resin material, but the resin material itself may be deformed or scratched at the interface between the metal film and the resin material. Occurs, and even the scratches are transferred to the surface of the molded product.

  In the technique disclosed in JP-A-5-38721, although quenching of the molten thermoplastic resin injected into the cavity can be suppressed, there are many voids on the surface of the ceramic sprayed layer. When molten thermoplastic resin penetrates into the gap and the molded product is released from the mold, the ceramic sprayed layer is destroyed or many irregularities are transferred to the surface of the molded product, making it impossible to obtain a high-quality molded product. Have a problem. It is also disclosed that a very thin (several μm) silicone-based paint is applied to flatten the surface of the ceramic sprayed layer, but a problem with durability tends to occur.

  In the insert 25 disclosed in Example 5 of Japanese Patent Application Laid-Open No. 2004-175112, the sealing layer 28 is formed by an electroless plating method. Generally, the heat insulating layer 27 is formed by a thermal spraying method. Since there are many voids, the following problems are likely to occur when the sealing layer 28 is formed by the electroless plating method. That is, when there are many deep voids in the heat insulating layer 27, the plated layer grows while entraining hydrogen bubbles generated in the plating step, and as a result, pinholes are likely to occur frequently in the sealing layer 28. In particular, the adhesion of the sealing layer 28 to the heat insulating layer 27 is reduced due to a large pinhole generated in a large portion of the void or the influence thereof. Then, a problem that the pinhole generated in the sealing layer 28 is transferred to the surface of the molded product, or a part of the molded product enters the pinhole generated in the sealing layer 28, and the molded product is released from the mold. At this time, the problem that the sealing layer 28 is damaged is likely to occur.

  Accordingly, an object of the present invention is to provide a molded article made of a polycarbonate resin composition that has a high-class feeling, has a high gloss and deep color tone, and has no weld line or warpage, and an injection molding method thereof.

The molded article made of the polycarbonate resin composition according to the first aspect of the present invention for achieving the above object (hereinafter referred to as “the molded article according to the first aspect of the present invention” for convenience),
(A) A first mold part, a second mold part, and a molten resin injection part provided in the first mold part, and a cavity formed by clamping the first mold part and the second mold part. A mold in which is formed, and
(B) Nesting arranged in the first mold part and / or the second mold part,
With
Nesting is
(A) metal block,
(B) a metal underlayer having a thickness of 0.03 mm to 1 mm formed on at least the surface of the metal block facing the cavity; and
(C) a thermal spray coating made of ceramics formed on a metal underlayer;
Consists of
The thermal spray coating has a porosity that varies in the thickness direction,
The porosity is a molded product made of a polycarbonate resin composition formed by using a mold assembly having a lower value on the side closer to the sprayed coating surface,
The maximum height R _z of the contour curve is 0.2 μm or less, the average length RSm of the contour curve element is 25 μm or less, and the reflectance at 400 nm to 650 nm measured by a spectrophotometer is 0.7%. It is characterized by the following.

The maximum height R _z of the contour curve, the average length of the profile elements RSm, arithmetic average height R _a of the contour curve, JIS B0601: as specified in 2001. As the reflectance, the reflectance at 400 nm to 650 nm was measured using a self-recording spectrophotometer (Shimadzu UV-3100PC). The smaller the reflectivity, the deeper the black color, and the jet blackness appears to increase.

The molded product made of the polycarbonate resin composition according to the second aspect of the present invention for achieving the above object (hereinafter referred to as “the molded product according to the second aspect of the present invention” for convenience),
(C) a metal film having a thickness of 0.03 mm to 0.5 mm disposed on the surface of the nest, forming a surface constituting the cavity;
Is formed using the above-described mold assembly for forming the molded product according to the first aspect of the present invention.

In order to achieve the above object, the injection molding method according to the first aspect or the second aspect of the present invention is such that the maximum height R _z of the contour curve is 0.2 μm or less and the average length of the contour curve elements. This is an injection molding method of a molded product made of a polycarbonate resin composition having an RSm of 25 μm or less and a reflectance at 400 nm to 650 nm measured by a spectrophotometer of 0.7% or less.

In the injection molding method according to the first aspect of the present invention, the mold assembly for molding the molded product according to the first aspect of the present invention described above is used, and the second aspect of the present invention is used. In the injection molding method according to the aspect, using the mold assembly for molding the molded article according to the second aspect of the present invention described above,
(A) After forming the cavity by clamping the first mold part and the second mold part, the molten polycarbonate resin composition is injected into the cavity from the molten resin injection part,
(B) The polycarbonate resin composition in the cavity is cooled and solidified, and then the obtained molded product is released from the mold.
It comprises the process.

In the molded product according to the first aspect of the present invention or the molded product made of the polycarbonate resin composition obtained by the injection molding method according to the first aspect of the present invention, the maximum height R _z of the contour curve is described above. The portion satisfying the regulation of the average length RSm and the reflectance of the contour curve element is the portion that was in contact with the thermal spray coating during the injection molding. Further, in the molded article according to the second aspect of the present invention or the molded article made of the polycarbonate resin composition obtained by the injection molding method according to the second aspect of the present invention, the maximum height R _z of the above contour curve The portion satisfying the regulation of the average length RSm and the reflectance of the contour curve element is the portion in contact with the metal film at the time of injection molding.

  The molded article according to the first aspect of the present invention or the molded article according to the second aspect of the present invention may be collectively referred to as “the molded article of the present invention” hereinafter. The injection molding method according to the aspect or the second aspect may be collectively referred to as “the injection molding method of the present invention”, and the molded product of the present invention and the injection molding method of the present invention may be collectively referred to as “ Hereinafter, it may be referred to as “the present invention”. Further, the molded product according to the first aspect of the present invention or the injection molding method according to the first aspect of the present invention may be collectively referred to as “first aspect of the present invention” hereinafter. Hereinafter, the molded product according to the second aspect of the invention or the injection molding method according to the second aspect of the present invention may be collectively referred to as “second aspect of the present invention”.

  In the injection molding method of the present invention, a solid molded product can be molded.

  Alternatively, in the injection molding method of the present invention, a mold assembly further including a pressurized fluid injection nozzle communicated with the cavity is used, and in the step (a), the molten polycarbonate resin composition is formed from the molten resin injection portion. A mode in which injection of pressurized fluid is started from a pressurized fluid injection nozzle into a molten polycarbonate resin composition injected into a cavity during injection of an object into the cavity, simultaneously with the completion of injection, or after completion of injection. It can be. Such an injection molding method in which a pressurized fluid is injected may be referred to as a gas assist molding method. By adopting the gas assist molding method, a molded product having a hollow portion can be obtained. When the gas assist molding method is adopted, the amount of the molten polycarbonate resin composition injected into the cavity may be an amount that completely fills the cavity (a so-called full shot method) or an amount that is incompletely filled. (So-called short shot method) may be used, but when forming a molded product with a small thickness, it is preferable to adopt the full shot method. The pressurized fluid is a gas substance at normal temperature and normal pressure, and preferably does not react or mix with the polycarbonate resin composition to be used. Specific examples include nitrogen gas, air, carbon dioxide gas, helium and the like, and nitrogen gas and helium gas are preferable in consideration of safety and economy. For example, the pressurized fluid injection nozzle may be disposed in the first mold part, may be disposed in the second mold part, or both the first mold part and the second mold part. You may arrange in. The pressurized fluid injection nozzle is positioned in the first mold so that the tip of the pressurized fluid injection nozzle is located in the cavity or in the vicinity of the surface constituting the cavity of the first mold part or the second mold part. It is preferable to arrange in the part or the second mold part. The rear end portion of the pressurized fluid injection nozzle is connected to a pressurized fluid source via, for example, a pipe. A moving means is attached to the rear of the pressurized fluid injection nozzle. Alternatively, the pressurized fluid injection nozzle may be arranged such that the tip of the pressurized fluid injection nozzle is disposed in the molten resin injection portion, and the mold assembly is an injection provided with an injection cylinder. It is attached to the molding machine, the injection cylinder and the molten resin injection part are in communication, and pressurized fluid injection is performed so that the pressurized fluid injection nozzle is placed at the tip (nozzle part) of the injection cylinder It is good also as a structure which arrange | positions a nozzle.

  In the present invention including the above preferred configuration, the surface of the metal block facing the cavity may be formed on the entire surface of the metal block, or the surface of the metal block facing the cavity. It can also be set as the form by which the sprayed coating is formed in a part of.

  In the present invention including the preferred configurations and forms described above, the thermal spray coating that is a coating formed by thermal spraying may be composed of the same composition from the viewpoint of composition (referred to as the same composition coating for convenience). A gradual coating film in which the composition of the thermal spray material is continuously changed between the layers can also be used. In addition, the sprayed coating may be composed of a single layer (referred to as a single-layer sprayed coating) from the viewpoint of the change in porosity, or from a multilayer structure of multiple layers (for convenience, each layer is referred to as a unit layer). It may be configured. The composition of each of the plurality of unit layers may be the same or different. Further, as described above, the thermal spray coating has a porosity changed in the thickness direction, but the state of the porosity change gradually (continuously from the interface between the metal underlayer and the thermal spray coating toward the surface of the thermal spray coating. (A) may be reduced, may be reduced stepwise, or may be gradually (continuously) reduced stepwise. When the thermal spray coating is composed of a single-layer thermal spray coating having the same composition or a gradually changing coating, it is possible to obtain a thermal spray coating having a porosity changed in the thickness direction depending on the thermal spraying conditions and the like. Further, when the thermal spray coating is constituted by a laminated structure of a plurality of unit layers, the porosity in each of the unit layers constituting the laminated structure of the plurality of layers can be varied depending on the thermal spraying conditions or the like.

  Further, in the present invention including the preferred configuration and form described above, the thermal conductivity of the thermal spray coating is 1 W / (m · K) to 4 W / (m · K), and the average thickness of the thermal spray coating. Is preferably 0.3 mm to 2.0 mm.

  When the thermal conductivity value of the thermal spray coating is below the lower limit of the above range, it may be difficult to obtain a desired porosity of the thermal spray coating. On the other hand, when the thermal conductivity value of the thermal spray coating exceeds the upper limit of the above range, for example, it is possible to suppress rapid cooling of the molten polycarbonate resin composition in contact with the thermal spray coating or in contact with the thermal spray coating through a metal film. It becomes difficult and the appearance improving effect of the molded product may be reduced. The thermal conductivity of the thermal spray coating can be measured based on a method such as a laser flash method or a hot wire method.

  In addition, for example, in order to suppress the rapid cooling of the molten polycarbonate resin composition in contact with the sprayed coating or in contact with the sprayed coating through a metal film, the sprayed coating is composed of a single layer sprayed coating. In this case, the average thickness of the thermal spray coating is desirably 0.3 mm to 2.0 mm, preferably 0.3 mm to 1.0 mm as described above. On the other hand, when the thermal spray coating is composed of a laminated structure of a plurality of unit layers, the average thickness (total thickness average) of the thermal spray coating is 0.5 mm to 1.8 mm, preferably 1.0 mm to 1.5 mm. It is desirable that the average thickness of the unit layer (sometimes referred to as a top coat) constituting the surface of the sprayed coating is 0.05 mm to 0.3 mm, preferably 0.1 mm to 0.2 mm. The average thickness of the unit layer (sometimes referred to as an intermediate layer) is 0.1 mm to 0.5 mm, preferably 0.2 mm to 0.4 mm, and the number of unit layers is 2 to 4, preferably 2 to 3. The thickness (film thickness) of the thermal spray coating is applied to the cut cross section by polishing or lapping as necessary, and the cross section is measured with a digital microscope, optical microscope, scanning electron microscope (SEM), laser microscope, etc. It can be measured based on the method of observing and measuring the thickness.

Furthermore, in the present invention including the preferred configurations and forms described above, in a portion up to a thickness of 0.05 mm from the surface of the thermal spray coating toward the inside of the thermal spray coating (referred to as the surface region of the thermal spray coating for convenience). The average value of the porosity is 0.4% or more and less than 5%, and the portion from the interface between the metal base layer and the thermal spray coating to the thickness of 0.2 mm (referred to as the bottom region of the thermal spray coating for convenience). The average porosity is preferably 5% or more and 10% or less. When converted into the average porosity calculated from the apparent density, the average porosity in the surface area of the sprayed coating is 3% or more and less than 10%, and the average porosity in the bottom area of the sprayed coating is 10% or more and 20%. % Or less. Alternatively, in the present invention including the preferred configurations and forms described above, the thermal spray coating is formed in a portion (surface region of the thermal spray coating) having a thickness of 0.05 mm from the surface of the thermal spray coating toward the inside of the thermal spray coating. The average particle size of the material is 2 × 10 ⁻⁶ m (2 μm) to 5 × 10 ⁻⁵ m (50 μm), and the thickness is 0.2 mm from the interface between the metal underlayer and the sprayed coating toward the inside of the sprayed coating. The average particle diameter of the material constituting the thermal spray coating in the above portion (bottom region of the thermal spray coating) is preferably 2 × 10 ⁻⁵ m (20 μm) to 1 × 10 ⁻⁴ m (100 μm).

  The average particle size of the material constituting the thermal spray coating in the surface area of the thermal spray coating is desirably as small as possible, but if it is too small, it is difficult to convey the raw material powder (ceramic particles) in the thermal spraying process for forming the thermal spray coating. There is a risk of becoming. Therefore, from the viewpoint of facilitating the formation of the sprayed coating or preventing the occurrence of cracks in the sprayed coating, the surface of the sprayed coating from the raw material powder (ceramic particles) having an average particle diameter in the above range. It is preferable to constitute a region. On the other hand, the average particle size of the material constituting the thermal spray coating in the bottom region of the thermal spray coating is within the above range, achieving the desired porosity and improving the heat insulation, and the influence of unevenness on the surface of the thermal spray coating. Further, it is preferable from the viewpoint of not generating cracks in the sprayed coating.

  Here, the average particle size is defined as a particle size at which the cumulative particle size of the powder is 50%, and can be measured based on, for example, a light transmission sedimentation method.

In the present invention including the various preferable configurations and forms described above, the surface roughness (maximum height of the contour curve) R _z on the surface of the thermal spray coating is desirably 0.15 μm or less. The maximum height R _z of the contour curve is obtained by subjecting the surface of the thermal spray coating to a mirror lapping process with fine diamond abrasive grains and the like. The maximum roughness (height) is selected from the obtained roughness curve data by scanning several times under the conditions of a thickness of 0.8 mm, a cutoff of 0.8 mm, and a measurement speed of 0.05 mm / second. It can be measured based on a method of obtaining an average value. Here, as described above, by setting the porosity average value in the surface area of the thermal spray coating within the above range, the thermal spray coating surface becomes a very dense surface state, for example, the surface of the thermal spray coating after lapping The maximum height R _z of the contour curve can be easily reduced to 0.15 μm or less. If the porosity exceeds the upper limit of the above range, fine irregularities remain on the surface of the sprayed coating even if lapping is performed, for example, the irregularities are transferred to the surface of the molded product, resulting in a slight haze in the appearance of the molded product. There is a fear. On the other hand, it is technically difficult to make the porosity less than the lower limit of the above range. The lapping process can be performed using, for example, diamond powder, chemical polishing liquid, or the like, and the number of abrasive particles may be 5000 or higher as the final finish. In addition, by setting the maximum height R _z of the contour curve on the surface of the thermal spray coating to 0.15 μm or less, for example, the metal film can be detachably mounted on the surface of the nesting (more specifically, on the surface of the thermal spray coating). When disposed (placed), the metal film can be reliably prevented from being deformed (for example, dented) by the pressure of the molten polycarbonate resin composition injected into the cavity.

  In the present invention, the porosity is defined as the ratio of the area occupied by the pores to a certain area in the cross section of the coating, and the average porosity is measured, for example, in the thickness direction of the thermal spray coating. After cutting and obtaining a cross-sectional image with a digital microscope, an optical microscope, a scanning electron microscope (SEM), a laser microscope, etc., the porosity is obtained from the contrast difference of the image using an image analyzer, and further The average value can be obtained from the obtained porosity. In the present invention, the pores that are voids contained in the thermal spray coating include both open pores (open holes) and closed pores (closed holes).

  In the present invention including the various preferable configurations and forms described above, examples of the material constituting the metal block (also referred to as a base) that is the surface to be sprayed of the material include carbon steel and stainless steel. The term metal block includes a metal block made of an alloy.

  The metal underlayer is required to firmly adhere the thermal spray coating to the metal block. As its composition, Ni—Cr, and more specifically, Ni-20% Cr, Ni-50% Cr, Ni Examples thereof include -16% Cr-20% Fe, Ni-19% Cr-6% Al, Ni-55% Cr-2.5% Mo-0.5% B, and the like. The term “metal underlayer” includes an underlayer made of an alloy. If the thickness of the metal underlayer is less than 0.03 mm, it is difficult to obtain strong adhesion to the metal block. On the other hand, if the thickness exceeds 1 mm, peeling occurs at the interface between the metal underlayer and the metal block during spraying of the coating. There is a fear. The upper limit value of the thickness of the metal underlayer is preferably 0.5 mm, more preferably 0.3 mm, and this causes peeling at the interface between the metal underlayer and the metal block during spraying of the coating. This can be reliably prevented, and the durability of the sprayed coating can be improved. The metal underlayer can be formed based on various spraying methods such as a plasma spraying method, an HVOF method, and a spraying method using a wire. The metal underlayer formed based on the thermal spraying method is also referred to as an undercoat spray coating, an undercoat, or a bond coat.

Examples of ceramics constituting the thermal spray coating include zirconium oxide and aluminum oxide. Here, as the composition of zirconium oxide, more specifically, CaO stabilized zirconia (5% CaO—ZrO ₂ , 8% CaO—ZrO ₂ , 31% CaO—ZrO ₂ ), MgO stabilized zirconia (20% MgO). _{-ZrO 2, 24% MgO-ZrO} 2), Y 2 O 3 stabilized zirconia _{(6% Y 2 O 3 -ZrO} 2, 7% Y 2 O 3 -ZrO 2, 8% Y 2 O 3 -ZrO 2, 10% Y ₂ O ₃ —ZrO ₂ , 12% Y ₂ O ₃ —ZrO ₂ , 20% Y ₂ O ₃ —ZrO ₂ ), zircon (ZrO ₂ −33% SiO ₂ ), CeO stabilized zirconia. More specifically, the composition of aluminum oxide is more specifically white alumina (Al ₂ O ₃ ), gray alumina (Al ₂ O ₃ -1.5 to 4% TiO ₂ ), alumina / titania (Al ₂ O _3). -13% TiO _2, Al ₂ O ₃ -20% TiO ₂ , Al ₂ O ₃ -40% TiO ₂ , Al ₂ O ₃ -50% TiO ₂ ), alumina yttria (3Al ₂ O ₃ .5Y ₂ O ₃ ), alumina magnesia (Mg. Al ₂ O ₄ ) and alumina / silica (3Al ₂ O ₃ .2SiO ₂ ) can be mentioned, and particularly preferred is zirconium oxide which can easily control the porosity. However, “%” means% by weight.

The thermal spray coating is formed by a thermal spraying method. Specific examples of the thermal spraying method include a plasma powder spray method and an HVOF method. In order to form a portion having a thickness of at least 0.05 mm from the surface of the thermal spray coating to the inside of the thermal spray coating, the flying speed of the ceramic particles (powder) is preferably 2 × 10 ² m / second or more. . The film thickness during thermal spraying is desirably 1 × 10 ⁻⁴ m (100 μm) / pass or less in order to obtain a dense film. As the thermal spraying device, it is preferable to use a plasma spraying device capable of increasing the flight speed or an HVOF (High Velocity Oxygen Fuel Spraying) device which is a kind of high-speed flame spraying device.

  During thermal spraying, it is desirable to forcibly cool the sprayed material from the front surface and back surface of the sprayed material in order to prevent cracks from being generated in the coating due to thermal expansion due to the generated heat. Compressed air can be used for cooling. In addition, a water cooling block etc. can also be used for cooling from the back surface of a thermal spray. Then, while confirming the state of occurrence of cracks, the test may be performed by changing the cooling conditions as appropriate to determine the optimal cooling conditions.

Furthermore, in the second aspect of the present invention including the preferred configurations and forms described above, the metal film is made of at least one material selected from the group consisting of chromium, a chromium compound, nickel, and a nickel compound. Preferably it consists of: In this case, the metal film is preferably formed on the sprayed coating by plating. Examples of plating methods include electroplating, electroless plating, chemical plating, or a combination thereof. In this case, the metal film may be formed on the cavity surface of the thermal spray coating, and may be formed on the entire surface of the thermal spray coating, for example. Alternatively, in the second aspect of the present invention including the preferred configuration and form described above, the maximum height R _z of the contour curve of the surface of the metal film is 0.03 μm or less, and the surface of the metal film May be flat or smooth (for example, mirror surface). Even when a metal film is provided, the surface roughness (maximum height of the contour curve) R _z of the sprayed coating surface is preferably 0.15 μm or less. Alternatively, in the second aspect of the present invention including the various preferred configurations and forms described above, the metal film is made of nickel-phosphorus alloy or nickel and is detachably disposed on the surface of the nest. In this case, the metal film may be produced by electroforming using, for example, a smooth glass surface as a mother type.

  In the second aspect of the present invention, a metal film is disposed on the surface of the nest (more specifically, on the thermal spray coating). It can be determined depending on the situation. For example, if the metal film has a structure (so-called stamper structure) in which the metal film is detachably disposed on the surface of the insert, a molded product having an appearance defined in the molded product of the present invention can be obtained only on the flat surface portion. . Therefore, although it can be applied only to the flat portion of the molded product, the metal film can be provided at low cost. On the other hand, if the metal film is formed on the thermal spray coating by plating, it can be applied to a molded product having a three-dimensional shape (a shape having a three-dimensional curved surface). When the metal film is detachably disposed (placed) on the cavity surface of the nest, the metal film is nested so that the metal film does not move due to the flow of the molten polycarbonate resin composition injected into the cavity during molding. It is good also as a structure fixed to the cavity surface of a nesting by the vacuum suction in the peripheral part. Specifically, a through hole is provided in the periphery of the nest, a metal film is disposed (placed) on the cavity surface of the nest so as to close the through hole, and the through hole is connected to a vacuum suction device. That's fine.

  In the second aspect of the present invention including various preferred configurations and forms described above, as described above, the metal film is at least one material selected from the group consisting of Cr, Cr compound, Ni and Ni compound. Preferably it consists of. The metal film may be composed of one layer or a plurality of layers. Specific examples of the Cr compound include a nickel-chromium alloy. Specific examples of Ni compounds include nickel-iron alloys, nickel-cobalt alloys, nickel-tin alloys, nickel-phosphorus alloys (Ni-P series), nickel-iron-phosphorus alloys (Ni-Fe-P series). ), Nickel-cobalt-phosphorus alloys (Ni-Co-P-based).

  The metal film has a thickness of 0.01 mm to 0.5 mm, preferably 0.1 mm to 0.3 mm. If the thickness of the metal film is less than 0.01 mm, the transferability tends to improve, but since the durability of the metal film becomes poor, depending on the damage, deformation, and form of the metal film, There is a possibility of causing peeling of the metal film from the surface. On the other hand, when the thickness of the metal film exceeds 0.5 mm, cooling of the molten polycarbonate resin composition injected into the cavity is promoted, so that transferability tends to be inferior.

In the present invention, a hard thin film may be formed on the surface of the sprayed coating. As a result, it is possible to prevent the surface of the sprayed coating from being damaged due to friction on the surface of the sprayed coating caused by the expansion and contraction of the metal film due to the heat of the molten polycarbonate resin composition injected into the cavity. Furthermore, it is possible to prevent the surface of the sprayed coating from being damaged when the mold is handled. In this case, examples of the material constituting the thin film include materials selected from the group consisting of TiN, TiAlN, TiC, CBN, BN, amorphous diamond, CrN and Cr, and amorphous diamond or TiN and CrN are particularly preferable. . Moreover, the thin film should just be formed at least 1 layer, and may be a multilayer. For example, a thin film made of TiN may be formed on the surface of the thermal spray coating, and a thin film of amorphous diamond, CrN, or the like may be formed thereon. Alternatively, a SiO ₂ layer may be formed on the surface of the sprayed coating as a base layer, and a thin film such as amorphous diamond, TiN, or CrN may be formed thereon. As a method for forming a thin film on the surface of the sprayed coating, chemical vapor deposition (CVD) such as atmospheric pressure CVD, low pressure CVD, thermal CVD, plasma CVD, photo CVD, laser CVD, vacuum deposition Examples thereof include physical vapor deposition methods (PVD methods) such as a method, sputtering method, ion plating method, ion beam vapor deposition method, and IVD method (ion vapor deposition method).

The thickness of the thin film is 5 × 10 ⁻⁷ m to 2 × 10 ⁻⁵ m, preferably 1 × 10 ⁻⁶ m to 1.5 × 10 ⁻⁵ m, more preferably 2 × 10 ⁻⁶ m to 1. It is desirable to be 0 × 10 ⁻⁵ m. The surface roughness (maximum height of the contour curve) R _z of the thin film surface is 1 nm to 19 nm, preferably 1 nm to 10 nm. When the thickness of the thin film is less than 5 × 10 ⁻⁷ m, the strength of the thin film is reduced, and the thin film may be peeled off from the nest during molding. On the other hand, when the thickness of the thin film exceeds 2 × 10 ⁻⁵ m, the heat insulating property is lowered, the transferability starts to be lowered, and the cost required for forming the thin film is increased. Furthermore, by defining the surface roughness of the thin film surface as described above, the adhesion of the metal film to the sprayed coating surface can be improved. For example, the metal film can be prevented from shifting from the nest during molding of the molded product. In addition, transferability is improved.

  A 1st metal mold | die part and a 2nd metal mold | die part can be produced from metal materials, such as carbon steel, stainless steel, an aluminum alloy, and a copper alloy. In addition, it is possible to adopt a pinpoint gate structure, a side gate structure, a film gate structure, or a multi-point gate structure with a hot runner as the structure of the molten resin injection part, so that the molten polycarbonate resin composition injected into the cavity It is desirable from the viewpoint of improving fluidity. The molten resin injection part is provided in the first mold part, but may be provided in the first mold part and the second mold part depending on the structure. In the present invention, for example, the first mold part may be a fixed mold part and the second mold part may be a movable mold part.

  The molded article of the present invention is a molded article made of a polycarbonate resin composition molded by the injection molding method according to the first aspect or the second aspect of the present invention including the various preferred configurations and forms described above. . Here, the shape of the part facing the nesting may be at least a plane or a curved surface. Furthermore, in the molded article of the present invention including such a form, it is possible to adopt a form in which a hole or an opening is formed in a portion facing the insert.

  Specific examples of the molded article of the present invention include a mobile phone casing, a PDA casing, a portable music player casing, a game machine casing, and a notebook personal computer casing. Such a molded article is portable and carried, and there is a high demand for a polycarbonate resin composition having excellent strength as a molding material.

  The molding material in the present invention is a polycarbonate resin composition in which a colorant comprising a combination of two or more dyes, or carbon nanotubes, or a colorant comprising a combination of two or more dyes and carbon nanotubes are added to a polycarbonate resin. It is characterized by comprising. That is, the polycarbonate resin composition in the molded article or the injection molding method according to the first aspect or the second aspect of the present invention including the various preferable configurations and forms described above comprises the polycarbonate resin composition.

  The preferred blending amount of two or more dyes is 0.005% to 1% by weight, more preferably 0.02% to 0.5% by weight, based on the total amount of the dyes. If it is less than such a blending amount, it is inferior in jetness, and if it is too much, problems such as uneven color in black or contamination of the mold during molding occur. Further, the preferable blending amount of the carbon nanotube is 0.005 wt% to 5 wt%, more preferably 0.02 wt% to 1 wt%. If it is less than such a blending amount, it is inferior in jetness, and if it is too much, color unevenness is produced in black. Moreover, since addition more than necessary is expensive, it increases a cost, and is not preferable.

  By using such a molding material, for example, high-quality jetness can be obtained. Moreover, the molded product of the present invention obtained on the basis of such a molding material as a black pigment, which is usually used, can obtain a jet blackness with an exceptionally superior luxury. .

  As the polycarbonate resin constituting the polycarbonate resin composition, an aromatic polycarbonate resin, an aliphatic polycarbonate resin, and an aromatic-aliphatic polycarbonate resin can be used, and among them, an aromatic polycarbonate resin is preferable. Here, the polycarbonate resin is a thermoplastic aromatic polycarbonate polymer or copolymer obtained by reacting an aromatic dihydroxy compound with phosgene or a diester of carbonic acid.

  As the raw material aromatic dihydroxy compound, 2,2-bis (4-hydroxyphenyl) propane [= bisphenol A], tetramethylbisphenol A, bis (4-hydroxyphenyl) -p-diisopropylbenzene, hydroquinone, resorcinol, and One or more selected from 4,4′-dihydroxydiphenyl and the like can be mentioned, and bisphenol A is preferable. Furthermore, for the purpose of further improving the flame retardancy, a compound in which one or more tetraalkylphosphonium sulfonates are bonded to the above aromatic dihydroxy compound, or a polymer or oligomer having a siloxane structure and containing both terminal phenolic OH groups is used. can do.

  The polycarbonate resin is preferably a polycarbonate resin derived from 2,2-bis (4-hydroxyphenyl) propane, or 2,2-bis (4-hydroxyphenyl) propane and another aromatic dihydroxy compound. And a polycarbonate copolymer derived from the above. Further, two or more kinds of polycarbonate resins may be used in combination.

The molecular weight of the polycarbonate resin is 1.4 × 10 ^{4 to} 3.0 × 10 ⁴ in terms of viscosity average molecular weight (Mv) converted from the solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent. The range is preferably 1.5 × 10 ^{4 to} 2.8 × 10 ⁴ , more preferably 1.6 × 10 ^{4 to} 2.6 × 10 ⁴ . If the viscosity average molecular weight is less than 1.4 × 10 ⁴ , the mechanical strength is insufficient, and if it exceeds 3.0 × 10 ⁴ , moldability tends to be difficult, which is not preferable.

  The method for producing such a polycarbonate resin is not limited, and the polycarbonate resin can be produced by a phosgene method (interfacial polymerization method), a melting method (transesterification method), or the like. Furthermore, it is also possible to use a polycarbonate resin produced by a melting method and having an adjusted amount of terminal OH groups.

  As the aromatic polycarbonate resin, not only a virgin resin but also an aromatic polycarbonate resin regenerated from a used product, a so-called material recycled aromatic polycarbonate resin may be used. As used products, for example, optical recording media such as optical disks, light guide plates, automotive window glass equivalents, automotive headlamp lenses, vehicle transparent members such as windshields, containers such as water bottles, eyeglass lenses, Examples of the building material include soundproof walls, glass window equivalents, and corrugated sheets. Further, non-conforming products, pulverized products obtained from sprues, runners, etc., or pellets obtained by melting these can be used. The ratio of the recycled aromatic polycarbonate resin is usually 80% by weight or less, preferably 50% by weight or less based on the virgin resin.

  Examples of the dye constituting the colorant composed of a combination of two or more dyes include anthraquinone, perinone, perylene, azo, methine, and quinoline dyes. From the viewpoint of excellent properties, the colorant preferably contains at least one anthraquinone dye. The dyes that make up the colorant have good thermal stability, and by mixing two or more primary colors (for example, red, purple, green, blue, yellow), the depth and clarity are particularly high and excellent. Although it will not restrict | limit especially if it is a dye which expresses jet blackness, Specifically, the following dyes can be illustrated.

  As an anthraquinone dye, Solvent Red 52, Solvent Red 111, Solvent Red 149, Solvent Red 150, Solvent Red 151, Solvent Red 168, Solvent Red 191, Solvent Red 207, Disperse Red 22, Disperse Red 60, Solvent Blue 35, Solvent Blue 36, Solvent Blue 63, Solvent Blue 78, Solvent Blue 83, Solvent Blue 87, Solvent Blue 94, Solvent Blue 97, Solvent Green 3, Solvent Green 20, Solvent Green 28, Disperse Violet 28, Solvent Violet 13, Solvent Violet 14, dyes such as Disperse Violet 31, Solvent Violet 36 and the like, which are commercially available.

  Examples of perinone-based dyes include dyes commercially available with color indexes such as Solvent Orange 60, Solvent Orange 78, Solvent Orange 90, Solvent Violet 29, Solvent Red 135, Solvent Red 162, and Solvent Red 179.

  Examples of perylene dyes include those commercially available with color indexes such as Solvent Green 5, Solvent Orange 55, Vat Red 15, Vat Orange 7, F Orange 240, F Red 305, F Red 339, and F Yellow 83. it can.

  As azo dyes, Solvent Yellow 14, Solvent Yellow 16, Solvent Yellow 21, Solvent Yellow 61, Solvent Yellow 81, Solvent Red 8, Solvent Red 23, Solvent Red 24, Solvent Red 27, Solvent Red 83, Solvent Red 84, Solvent Available in color indexes such as Red 121, Solvent Red 132, Solvent Violet 21, Solvent Black 21, Solvent Black 23, Solvent Black 27, Solvent Black 28, Solvent Black 31, Solvent Orange 37, Solvent Orange 40, Solvent Orange 45, etc. Can be mentioned.

  Examples of methine dyes include dyes commercially available with color indexes such as Solvent Orange 80 and Solvent Yellow 93. Examples of quinoline dyes include Solvent Yellow 33, Solvent Yellow 98, Solvent Yellow 157, Disperse Yellow 54, Disperse. Examples thereof include commercially available dyes with a color index such as Yellow 160.

  Carbon nanotubes have an outer region consisting of an essentially continuous multi-layer of regularly arranged carbon atoms and an inner hollow region, each layer and hollow region being substantially around the cylindrical axis of the fibril. Are essentially cylindrical fibrils arranged concentrically with each other. Furthermore, the regularly arranged carbon atoms in the outer region are preferably graphite-like, and the diameter of the hollow region is preferably 2 nm to 20 nm. Such carbon nanotubes are described in detail in Japanese Patent Publication No. 62-5000943 and US Pat. No. 4,663,230. As for the production method, as described in these patent publications and US patent specifications, transition metal-containing particles (for example, iron, cobalt, nickel-containing particles using alumina as a support) are converted into carbon such as CO and hydrocarbons. Examples include a method in which the contained gas is brought into contact at a high temperature of 850 ° C. to 1200 ° C., and carbon generated by pyrolysis is grown in a fiber form starting from a transition metal. Such carbon nanotubes are commercially available, for example, from Hyperion Catalysis under the trade name “Graphite Fibril”.

  In addition, an additive, a filler, and a reinforcing agent can also be added to the polycarbonate resin composition demonstrated above.

  Additives: Plasticizers; Stabilizers; Antioxidants: Ultraviolet absorbers; Ultraviolet stabilizers such as organic nickel compounds such as nickel bis (octylphenyl) sulfide, hindered amine compounds; Antistatic agents; Flame retardants; Vinadin, Priben Antifungal agents such as Thor and Thiabendazole; Lubricants such as liquid paraffin, polyethylene wax and fatty acid amide; Organic foaming agents such as ADCA; Transparent nucleating agents; Various colorants such as organic pigments, inorganic pigments and organic dyes; Crosslinking agents; Acrylic Mention may be made of impact-strengthening agents such as graft polymers and MBS.

  As stabilizers, organotin stabilizers such as di-n-octyltin compounds, di-n-butyltin compounds, and dimethyltin compounds; lead compound systems such as tribasic lead sulfate, dibasic lead phosphite, and lead silicate Stabilizers; metal soap-based stabilizers such as cadmium soap, lead soap, zinc soap; trisnonyl phosphate; trisnonylphenyl phosphate;

  Antioxidants such as phenolic antioxidants such as dibutylcresol and butylhydroxyanisole; bisphenolic antioxidants such as methylenebis (methylbutylphenol) and thiobis (methylbutylphenol); tris (methylhydroxybutylphenyl) butane and tocophenol And polyphosphoric antioxidants; organic sulfur compounds such as dimyristylthiodipropionate; and organic phosphorus compounds such as tris (mono / dinonylphenyl) phosphite.

  As UV absorbers, salicylic acid UV absorbers such as phenyl salicylate and butylphenyl salicylate; benzophenone UV absorbers such as dihydroxybenzophenone; benzotriazole UV absorbers such as (hydroxymethylphenyl) benzotriazole; ethylhexylcyanodiacrylate Examples include cyanoacrylate-based ultraviolet absorbers such as phenonyl.

  Antistatic agents such as poly (oxyethylene) alkylamines, poly (oxyethylene) alkylphenyl ethers, and other nonionic surfactant antistatic agents; alkylsulfonates, alkylbenzenesulfonates, alkylphosphates, etc. Examples include ionic surfactant-based antistatic agents; cationic surfactant-based antistatic agents such as quaternary ammonium chloride; amphoteric surfactants; and conductive resins.

  As flame retardants, halogen flame retardants such as tetrabromobisphenol A, polybromobiphenol, bis (hydroxydibromophenyl) propane, chlorinated paraffin; phosphorus flame retardants such as ammonium phosphate and tricresyl phosphate; antimony trioxide; red phosphorus ; Tin oxide etc. can be mentioned.

  As fillers and reinforcing agents, inorganic materials: stainless steel fibers, high-strength amorphous metal fibers, stainless steel foils, steel foils, copper foils and other metal materials; high-molecular polyethylene fibers, high-strength polyarate fibers, para-type all Organic materials such as aromatic polyamide fiber, aramid fiber, PEEK fiber, PEI fiber, PPS fiber, fluororesin fiber, phenol resin fiber, vinylon fiber, and polyacetal fiber;

  As inorganic fillers and reinforcing agents, glass materials such as glass fibers, long glass fibers, and quartz glass fibers; carbon materials such as PAN carbon fibers, pitch carbon fibers, and graphite whiskers; silicon carbide fibers, silicon carbide Silicon carbide materials such as continuous fibers, silicon carbide whiskers, silicon carbide whisker sheets; boron materials such as boron fibers; Si—Ti—C—O materials such as Si—Ti—C—O fibers; potassium titanate fibers, titanium Examples thereof include potassium titanate materials such as potassium acid whisker and potassium titanate conductive whisker; silicon nitride materials such as silicon nitride whisker and silicon nitride whisker sheet; and calcium sulfate materials such as calcium sulfate whisker.

  As powder filler and reinforcing agent, mica flake, mica powder, shirasu balloon, silica fine powder, talc powder, aluminum hydroxide powder, magnesium hydroxide powder, magnesium silicate powder, calcium sulfate fine powder, spherical hollow glass powder, metallization Powder, high purity synthetic silica fine powder, tungsten disulfide powder, tungsten carbide powder, zirconia fine powder, zirconia fine powder, partially stabilized zirconia powder, alumina-zirconia composite powder, composite metal powder, iron powder, aluminum powder, molybdenum metal Examples thereof include powder, tungsten powder, aluminum nitride powder, nylon fine particle powder, silicone resin fine powder, spinel powder, amorphous alloy powder, aluminum flake, and glass flake.

  When a mold made of steel is used and molding is performed with a molding material to which such a reinforcing agent is added, the reinforcing agent will usually be raised on the surface of the molded product. It becomes rough, and glossiness and jet blackness cannot be obtained. However, by adopting the injection molding method of the present invention, a molded article made of a polycarbonate resin composition having glossiness and jet blackness even when molding is performed using a molding material to which such a reinforcing agent is added. Can be obtained. The amount of the filler or reinforcing agent added is preferably 5% by weight or less, and more preferably 3% by weight, because if it is added in a large amount, the surface roughness of the molded product becomes rough and a jet black feeling may not be obtained. It is desirable to make the ratio less than or equal to%, whereby a molded product made of a polycarbonate resin composition having a jet black feeling with improved rigidity can be obtained without sacrificing surface properties.

  In addition, acrylic, urethane, epoxy, urethane acrylate, and silicone clear coating is applied to the molded product made of the polycarbonate resin composition of the present invention for the purpose of finally increasing the surface hardness of the molded product surface. It may be applied or a wax may be applied. Even with clear coating, there is no problem because there is no molding defect, and a thin film thickness is acceptable, so that only the surface hardness can be improved while maintaining the surface state of the molded product. The film thickness is preferably 10 μm or less.

In the molded product of the present invention, the maximum height R _{z of} the contour curve and the average length RSm of the contour curve element are defined, and the molded product of the present invention satisfying such regulations is very high-class. And has high gloss. Further, in the molded product of the present invention, the reflectance at 400 nm to 650 nm measured with a spectrophotometer is defined, and the molded product of the present invention that satisfies the regulation has a sense of depth and jetness. Is excellent.

In order to obtain a molded product having a high glossiness and a deep color tone, the surface roughness and reflectance of the molded product surface are important factors as well as no weld lines and warpage. If the surface roughness of the molded product exceeds 0.2 μm at the maximum height R _z of the contour curve, or the average length RSm of the contour curve element exceeds 25 μm, the molded product looks cloudy and has a sense of depth. It was found that it was not obtained. In particular, when the color of the molded product is black, such a phenomenon is remarkably recognized. Note that the surface appearance determination of whether there is a sense of depth in color tone is determined by the observer's sense. It was found that a deep jet black feeling cannot be obtained unless the reflectance of the spectrophotometer is 0.7% or less in the visible range of 400 nm to 650 nm with respect to black having a large color tone as a requirement. Moreover, even if it is the same black, when the reflectance in the visible region of 400 nm to 650 nm exceeds 0.7%, it feels more grayish than the sensitivity of human eyes, and does not feel a sense of depth, It detracts from the luxury. In addition, what is necessary is just to obtain | require the reflectance for every wavelength range by cut | disconnecting a molded article to about 10 mm x 25 mm square, and measuring with a spectrophotometer.

  Moreover, in this invention, the thermal spray coating as a heat insulation film is formed by the thermal spraying method. Therefore, various problems when the insert is made from a dense but brittle material such as a sintered body (a firing furnace problem, a crack problem during manufacturing, a problem of breakage during use, and a very high manufacturing cost. No problem occurs, and the nesting is not subject to various restrictions due to, for example, the structure of the mold, the shape of the cavity, or the molded product. Moreover, the thermal spray coating which has heat insulation property and is not easily damaged has a porosity changed in the thickness direction, and the porosity is lower as the side is closer to the surface of the thermal spray coating. That is, the surface of the sprayed coating is dense. Therefore, there are few unevenness | corrugations in the sprayed coating surface, and the sprayed coating surface is excellent in smoothness. Therefore, for example, the surface state of the metal film disposed on the surface of the sprayed coating is reflected in the state of the surface of the sprayed coating, but the surface state of the metal film is also excellent in smoothness. Therefore, there is no problem that a high-quality molded product cannot be obtained due to transfer failure or the like, and there is no problem in durability of the sprayed coating.

  Further, since the surface of the thermal spray coating is dense, for example, when a metal film is formed by a plating method, pinholes hardly occur in the metal film, and the thickness of the metal film can be reduced. Alternatively, since the surface of the thermal spray coating is dense, even when a stamper structure is adopted, the thermal spray particles do not fall off the nesting surface during molding, and the back surface of the metal film is worn during molding. Thus, it is possible to surely prevent the occurrence of problems such as the metal powder of the metal film being mixed in the molded product or the fine undulation occurring on the surface side of the metal film. In addition, it is possible to reduce the molding cost of the molded product and shorten the time [TAT (Turn Around Time)] required from the design of the molded product to the molding of the molded product as an actual product.

  When the porosity of the sprayed coating is very small, the roughness of the surface of the sprayed coating after lapping is reduced, but the thermal conductivity is increased. Further, such a sprayed coating is liable to generate cracks during production, and it is difficult to increase the film thickness. Therefore, by changing the porosity in the thickness direction of the thermal spray coating, making the vicinity of the surface dense and roughening the vicinity of the metal block, the thermal conductivity of the entire thermal spray coating is low, and after the lapping finish A sprayed coating having a small surface roughness can be obtained. In addition, since a thermal spray coating having a low thermal conductivity and a large thickness can be obtained, for example, in the injection molding process, the molten polycarbonate resin composition is rapidly cooled, resulting in poor appearance and transfer defects in the molded product. Can be reliably prevented from occurring. Furthermore, there is no generation of weld lines or flow marks, no warping or sinking, excellent transferability, very high gloss, and a molded product with very little distortion inside. Further, even when a hole or an opening is formed in the molded product, it is possible to reliably prevent the occurrence of a weld line as will be described later.

  Therefore, the surface is the same without using a conventional mold assembly that employs a complicated mold assembly as a countermeasure for preventing damage to the insert, using a insert made of a ceramic sintered body that is all dense. It is possible to provide a molded product having quality, that is, excellent appearance characteristics.

  Moreover, in the obtained molded product, even when it is molded using a polycarbonate resin composition containing a filler such as glass fiber, rapid cooling of the molten polycarbonate resin composition in the cavity can be prevented. In addition, the floatation of the filler can be prevented, and the rapid development of the solidified layer in the molten polycarbonate resin composition injected into the cavity can be suppressed, so that the fluidity of the molten polycarbonate resin composition in the cavity can be reduced. Compared to the case of nesting made from a normal steel material, there is an effect that it is increased by about 30 to 30%, and in particular, a thin molded product can be easily formed. Moreover, since it can be applied to a molded product having a three-dimensional curvature, the application range can be greatly expanded.

  When a hole or an opening is provided in the molded product, a metal first core member is provided in the first mold part, and a metal second core member is provided in the second mold part. Then, the cavity is formed by clamping the first mold part and the second mold part. In addition, in the state which clamped the 1st metal mold | die part and the 2nd metal mold | die part, the front-end | tip surface of a 1st core member and the front-end | tip surface of a 2nd core member will be in the state which contacted, or the state which faced. Then, the molten polycarbonate resin composition is injected into the cavity. As a result of the molten polycarbonate resin composition flowing around the core member and the surface of the polycarbonate resin composition merging with each other, the weld line and Frequently called streak lines occur. As a method for solving such a phenomenon, an annular sintered body (referred to as an annular sintered body) is produced, and the annular sintered body is inserted into the core member and bonded to the core member with an adhesive or the like. be able to. However, in such a method, the weld line can be eliminated, but it is necessary to produce an annular sintered body as a separate part from the insert that constitutes the cavity surface. There is a high risk of breakage when the first mold part and the second mold part are clamped. In particular, when the cavity has a complicated three-dimensional shape or part of a sphere, it cannot be accurately processed or bonded to the first mold part or the second mold part where the annular sintered body is to be fixed. Probability is high. Furthermore, a slight clearance is required between the annular sintered body and the insert to prevent breakage, and it becomes difficult to produce the annular sintered body and the insert.

  In the present invention, since the thermal spray coating is formed on the surface of the nesting by the thermal spraying process, the nesting can be easily performed even when the nesting constitutes a part of the cavity surface composed of a complicated three-dimensional shape or spherical surface. Can be produced. In addition, the generation of weld lines can be reliably prevented. Further, when a protrusion (corresponding to a core member) is provided in the insert in order to provide a hole or an opening in the molded product, a metal underlayer having a thickness of 0.03 mm to 1 mm is formed on the surface of the protrusion. A thermal spray coating made of ceramics may be formed on the metal underlayer. However, it is not necessary to form a metal underlayer and a sprayed coating on the contact surface or the opposing surface of the protrusion. In this case, a metal film may or may not be disposed on the thermal spray coating provided on the protrusion. Even in the above case, the thermal spray coating has a porosity that changes in the thickness direction, and the porosity needs to satisfy the requirement that the closer to the surface of the thermal spray coating, the lower the value. When the requirements are not satisfied, there is a possibility that the sprayed coating itself may be damaged by the polycarbonate resin composition entering the gap when the first mold part and the second mold part are released.

  Hereinafter, the present invention will be described based on examples with reference to the drawings.

  Example 1 relates to a molded article made of a polycarbonate resin composition according to the first aspect of the present invention, and an injection molding method according to the first aspect of the present invention.

  The molded product made of the polycarbonate resin composition of Example 1 (hereinafter, the molded product made of the polycarbonate resin composition may be simply referred to as “molded product”) was molded by the injection molding method of Example 1. Specifically, in Example 1, the molded product was a box-shaped housing model. More specifically, the molded product is a mobile phone casing. Since such a molded product is required to have strength and gloss, a polycarbonate resin composition is used as a molding material.

  Here, in Example 1 or Example 2 to Example 3 described later, the polycarbonate resin composition shown in Table 1 was used as the polycarbonate resin composition that is a raw material of the molded product. In Examples 4 to 6 described later, the polycarbonate resin compositions shown in Table 2 were used as the polycarbonate resin composition that is a raw material of the molded product. Incidentally, “Iupilon S-3000FN” manufactured by Mitsubishi Engineering Plastics Co., Ltd. was used as the polycarbonate resin. The polycarbonate resin is a bisphenol A type aromatic polycarbonate resin produced by an interfacial polymerization method, and has a viscosity average molecular weight ( Mv) is approximately 22500. Further, tris (2,4-di-tert-butylphenyl) phosphite (“ADK STAB AS2112” manufactured by Asahi Denka Kogyo Co., Ltd.) was used as a stabilizer. Furthermore, as carbon nanotubes, specifically, 85% by weight of polycarbonate resin, 15% by weight of hollow carbon fibrils (trade name: graphite fibril BN) having an outer diameter of 15 nm, an inner diameter of 5 nm, and a length of 0.1 μm to 10 μm. A masterbatch (trade name of Hyperion Catalysis: PC / 15BN) containing In the column of dyes in Tables 1 and 2, the product names are shown in the upper row, and the color index is shown in the lower row.

[Table 1]

[Table 2]

In Example 1, or Examples 2 to 6 described later and various comparative examples, the following compositions were used.
Example 1: Composition-A
Example 2: Composition-B
Example 3: Composition-C
Example 4: Composition-E
Example 5: Composition-F
Example 6: Composition-G
Comparative Examples 1A to 1D: Composition-A
Comparative Example 2A: Composition-B
Comparative Example 2B: Composition-D
Comparative Examples 4A-4D: Composition-E
Comparative Example 5A: Composition-F
Comparative Example 5B: Composition-H

  Since the molded product itself has become thinner due to the effects of weight reduction and cost reduction, in the conventional technology, molding, especially in the cavity, a molten polycarbonate resin composition (hereinafter referred to as “molten resin” for convenience). It is becoming difficult to completely fill the composition. Therefore, in order to completely fill the cavity with the molten resin composition, if a multi-point gate structure is adopted for the purpose of shortening the flow distance of the molten resin composition in the cavity, a weld line is generated and the filling pressure ( When the injection pressure) is increased, problems such as large warpage in the obtained molded product and appearance defects such as flow marks occur. Moreover, in terms of materials, for the purpose of improving fluidity, molecular weight is reduced or measures are taken together with a fluidity improver, etc., but due to the strength reduction of the molded product itself, damage at the time of dropping is caused. There's a problem.

  In addition, when a molded product is painted to improve the appearance of the molded product, there is a problem that the yield of coating is poor. Therefore, for the purpose of cost reduction and elimination of rough skin by painting, non-painted type molded products are being studied. That is, the appearance of the molded product is mirror polished. By the way, in the injection molding of a molded product, high gloss cannot be obtained unless the transferability of the mirror surface is increased. Therefore, it is necessary to increase the transferability. For this reason, when the mold temperature is increased, there arises a problem that the molding cycle becomes longer as a result. Moreover, since it has high gloss, warpage is easily noticeable. Thus, the conventional technique has various problems.

  The molded product of Example 1 has a box shape of 100 mm × 50 mm and a height of 5 mm.

As shown in FIG. 2, the mold assembly 10 of the first embodiment has a conceptual diagram.
(A) a first mold part (fixed mold part) 11, a second mold part (movable mold part) 12, and a molten resin injection part 14 provided in the first mold part 11, A mold in which a cavity 13 is formed by clamping the first mold part 11 and the second mold part 12, and
(B) Nests 20 </ b> A and 20 </ b> B that are arranged in the first mold part 11 and the second mold part 12 and form a surface constituting the cavity 13,
It has. The molten resin injection part 14 has a side gate structure with one gate.

Then, as shown in a schematic cross-sectional view in FIG. 1A and an enlarged schematic partial cross-sectional view in FIG.
(A) Metal blocks 31A, 31B,
(B) metal underlayers 32A and 32B having a thickness of 0.03 mm to 1 mm formed on at least the surfaces of the metal blocks 31A and 31B facing the cavity 13 (the top surfaces of the metal blocks 31A and 31B), and
(C) Thermal spray coatings 33A and 33B made of ceramics formed on the metal base layers 32A and 32B,
It is composed of The inserts 20A and 20B are fixed to the first mold part (fixed mold part) 11 and the second mold part (movable mold part) 12 using bolts (not shown).

  Here, the thermal spray coatings 33A and 33B have the porosity changed in the thickness direction, and the porosity is closer to the surface of the thermal spray coatings 33A and 33B (the portion closer to the surface of the thermal spray coatings 33A and 33B). ), Low value. In FIG. 1B or FIG. 1C described later, the pores are illustrated as being aligned, but in reality, the pores are randomly formed. Moreover, although the closed pore (closed hole) is illustrated exclusively, of course, an open pore (open hole) also exists.

Specifically, the metal blocks 31A and 31B are made of SUS420J2 (HPM38 manufactured by Hitachi Metals, Ltd.) having a linear expansion coefficient of 11.5 × 10 ⁻⁶ / ° C. at 20 ° C. to 200 ° C. Yes. Further, the metal base layers 32A and 32B having a thickness of 0.08 mm are required to firmly adhere the thermal spray coatings 33A and 33B to the metal blocks 31A and 31B, and the composition thereof is Ni—Cr (more specifically, Ni-20% Cr) and is formed on the top surfaces of the metal blocks 31A and 31B based on the thermal spraying method. The same applies to Example 2 to Example 6.

  Here, in the inserts 20A and 20B for forming a molded product, the shape of the insert 20A arranged in the first mold part 11 is a rectangular parallelepiped, and the external dimensions (vertical x horizontal x thickness) are: It is 140 mm × 90 mm × 30 mm, and the dimension length × width × depth of the portion (concave portion) of the insert 20A for molding the outer surface of the molded product is 100 mm × 50 mm × 5 mm. On the other hand, the shape of the insert 20B arranged in the second mold part 12 is a rectangular parallelepiped, and the outer dimensions (length × width × thickness) are 140 mm × 90 mm × 30 mm. Further, the dimension (vertical x horizontal x depth) of the portion (projection) of the insert 20B for molding the outer surface of the molded product is 96 mm x 46 mm x 3 mm.

In Example 1, the thermal spray coatings 33A and 33B are composed of two unit layers having different compositions, and are formed by a plasma spraying apparatus. Specifically, the first layer (lower layer) 33 ′ constituting the sprayed coatings 33A and 33B is made of ZrO ₂ , and the second layer (upper layer) 33 ″ is made of Al ₂ O ₃ . 33B has a mirror finish. The surface roughness (maximum height of the contour curve) R _z of the second layer (upper layer) 33 ″ is 0.1 μm.

  Table 3 shows the composition and thickness of the metal underlayer in Example 1 or Example 2 described later; the composition, layer configuration, total thickness, and thermal conductivity of the thermal spray coatings 33A and 33B; thermal spray coatings 33A and 33B. Composition, thickness, porosity average value, average particle diameter, surface roughness of the second layer (upper layer) unit layer 33 ″ or the thermal spray coatings 33A, 33B constituting the first layer constituting the thermal spray coatings 33A, 33B The composition (thickness), porosity average value, average particle size of the layer (lower layer) unit layer 33 ′; the average porosity of the surface region, the average particle size; the average porosity of the bottom region, and the average particle size are shown. .

  For comparison, in Table 4, the composition and thickness of the metal underlayer in Comparative Example 1A, Comparative Example 1B, and Comparative Example 1C; Composition of the entire sprayed coating, layer configuration, total thickness, thermal conductivity; Composition, thickness, porosity average value, average particle size, surface roughness of the second layer (upper layer) unit layer or thermal spray coating; composition of the first layer (lower layer) unit layer constituting the thermal spray coating, Thickness, average porosity, average particle size; average porosity of surface region, average particle size; average porosity, average particle size of bottom region.

  Here, in Comparative Example 1A, Comparative Example 1B, and Comparative Example 1C, the metal underlayer is not formed. In Comparative Example 1A, the thermal spray coating is composed of two unit layers having different compositions. In Comparative Example 1B, the thermal spray coating is composed of two unit layers having the same composition. In Comparative Example 1C, the thermal spray coating is composed of a single-layer thermal spray coating. In Comparative Example 1C, the thermal spray coating was formed so that the porosity value of the entire one thermal spray coating was the same.

[Table 3]

[Table 4]

  The injection molding conditions in Example 1 are illustrated in Table 5. In Examples 1 to 3, TR100EH manufactured by Sodick Plustech Co., Ltd. was used as the injection molding machine. And in Example 1, as shown in the conceptual diagram of the mold assembly 10A in FIG. 2, the first mold part (fixed mold part) 11 and the second mold part (movable mold part). 12 is clamped to form a cavity 13. After the polycarbonate resin composition (hereinafter referred to as “resin composition” for convenience) is plasticized, melted and measured in the injection cylinder 16, the runner part and the sprue are removed from the injection cylinder 16. The molten resin composition is injected into the cavity 13 through the part 15 and the molten resin injection part (gate part) 14 under the injection molding conditions shown in Table 5, and the cavity 13 is completely filled with the molten resin composition. Filled. Next, the resin composition in the cavity 13 was cooled and solidified, and then the obtained molded product was released from the mold.

  Table 5 shows the evaluation results of the molded product of Example 1. In Example 1, it was the molten resin injection part 14 having a side gate structure with one gate point, but the molded product has excellent transferability, no weld line, It had high gloss and deep jetness. Further, the molded product was free from warpage and was very luxurious. Further, although molding was performed 50,000 times, no damage or the like occurred in the inserts 20A and 20B.

    In addition, the diffuse reflectance of 450 nm-650 nm was measured in the plane part of a molded article using the Shimadzu UV-3100PC type | mold spectral altimeter. In the table, the reflectance of 450 nm is described.

  For comparison, when injection molding was performed using a nest made of steel, the cavity 13 could not be completely filled with the molten resin composition (Composition-A). Therefore, when the resin temperature was changed to 320 ° C. and the mold temperature was changed to 120 ° C. and injection molding was performed, the molten resin composition could be completely filled into the cavity 13, but the molded product was A weld line was generated, and a flow mark was generated around the weld line and in the vicinity of the molten resin injection portion 14, the appearance of the molded product was very ugly, and a jet black feeling was not obtained in the molded product. Moreover, since the resin composition is forcibly filled into the cavity 13, the molded product is warped. Table 5 shows the evaluation results of the molded product as Comparative Example 1D.

  When the surface of the sprayed coating obtained by Example 1 or Example 2 to Example 3 described later was visually observed, it had high gloss, the surface was smooth, and cracks were observed. There wasn't. On the other hand, in Comparative Example 1A, the surface of the sprayed coating was rough and the surface roughness was very rough. Moreover, when the surface of the thermal spray coating obtained by Comparative Example 1B was visually observed, cracks were generated. Furthermore, when the surface of the thermal spray coating obtained by Comparative Example 1C was visually observed, large irregularities were observed on the surface. In addition, the sample obtained in the comparative example was also peeled off at the interface with the metal block. Table 5 shows the evaluation results of the molded products obtained in Comparative Example 1A, Comparative Example 1B, and Comparative Example 1C.

  Example 2 is a modification of Example 1 and relates to the injection molding method according to the first aspect of the present invention, and adopted a gas assist molding method for molding a molded product having a hollow portion.

  In the second embodiment, using the mold used in the first embodiment, sink marks in the portion of the molded product facing the insert 20A disposed in the first mold portion 11 can be further reduced as compared with the first embodiment. A recess was provided on the outer peripheral portion of the insert 20B arranged in the second mold portion 12 so that a rib portion having a thickness of 2 mm was formed on the portion of the molded product facing the outer peripheral portion.

  Furthermore, in order to form a hollow part, a gas assist molding method using nitrogen gas as a pressurized fluid is executed. For this purpose, a pressurized fluid is introduced into the second mold part (movable mold part) 12. And a pressurized fluid injection nozzle 17 were installed. A moving means 18 comprising a hydraulic cylinder is attached to the rear part of the pressurized fluid injection nozzle 17.

The injection molding conditions in Example 2 are illustrated in Table 5. Even in the second embodiment, as shown in FIG. 3 which is a conceptual diagram of the mold assembly 10B, a first mold part (fixed mold part) 11, a second mold part (movable mold part) 12, and And the cavity 13 is formed. Then, the pressurized fluid injection nozzle 17 was moved in the direction toward the cavity 13 by the operation of the moving means 18 and positioned at the forward end (see FIG. 3). In this state, the pressurized fluid injection nozzle 17 communicates with the cavity 13. After the resin composition (Composition-B) is plasticized, melted and weighed in the injection cylinder 16, the injection cylinder 16 passes through the runner part and sprue part 15 and the molten resin injection part (gate part) 14. The molten resin composition was injected into the cavity 13 under the injection molding conditions shown in Table 5, and the cavity 13 was incompletely filled with the molten resin composition. That is, a part of the cavity 13 was filled with the molten resin composition. In Example 2, a molten resin composition having a capacity satisfying about 99% of the cavity volume was injected into the cavity 13. Immediately after completion of the injection, 1.5 × 10 ⁷ Pa (15 MPa) of nitrogen gas was injected into the molten resin composition in the cavity 13 from the pressurized fluid injection nozzle 17. Next, the resin composition in the cavity 13 was cooled and solidified, and then the obtained molded product was released from the mold. In Example 2, the mold was not provided with an overflow cavity communicating with the cavity 13, but an overflow cavity structure in which a part of the molten resin composition injected into the cavity 13 could flow during molding. It can also be used. In this case, since a part of the molten resin composition injected into the cavity 13 flows into the overflow cavity, it becomes easier to form a hollow portion.

  Table 5 shows the evaluation results of the molded product of Example 2. Since the gas-assisted molding method is adopted, there is no occurrence of sink marks in the vicinity of the molded product, especially the rib part, and the transferability is excellent, so the molded product has very high gloss and deep jetness. Was. Further, similarly to Example 1, there was no occurrence of a weld line generated when the molten resin compositions were joined together, and no “color unevenness” phenomenon which was a phenomenon peculiar to gas assist molding. The “color unevenness” is color unevenness generated as a result of the injected pressurized fluid being mixed with the molten resin composition near the cavity surface. Further, although molding was performed 50,000 times, no damage or the like occurred in the inserts 20A and 20B.

For comparison, when injection molding was performed using a nest made of steel, the cavity 13 could not be completely filled with the molten resin composition (composition-B), and nitrogen gas was introduced into the cavity 13. When injected into the molten resin composition, the resulting molded product had holes as defective portions. Therefore, when the injection pressure was changed to 1.5 × 10 ⁸ Pa (150 MPa) and gas assist molding was performed, the molten resin composition could be completely filled into the cavity 13, and the obtained molded product was obtained. Although the hole as a defective part was not opened, the glossiness and deep jet blackness were worse than those of Example 2, the weld line was generated, and the “color unevenness” phenomenon occurred. Therefore, it was impossible to obtain a molded product having an excellent appearance. Such a comparative example is referred to as Comparative Example 2A, and the evaluation results of the molded product are shown in Table 5. In addition, as a polycarbonate resin composition, a molded product obtained by injection molding under the same injection molding conditions as in Comparative Example 2A using Composition-D is referred to as Comparative Example 2B. As shown in FIG.

  In Example 3, using the mold assembly described in Example 1, and using the composition-C shown in Table 1, based on the same injection molding conditions as in Example 1, the same shape as in Example 1 The molded product was obtained. The evaluation results of the molded product are shown in Table 5. The molded product was very excellent in transferability, had no weld line, and had very high gloss and deep jetness.

[Table 5]

  Example 4 is also a modification of Example 1, but relates to a molded product according to the second aspect of the present invention and an injection molding method according to the second aspect of the present invention.

  The molded product of Example 4 is a molded product molded by the injection molding method of Example 4. Specifically, in Example 4, the molded product was a casing for a mobile phone. Here, the molded product is more specifically an outer cover (housing) having a small liquid crystal display device.

  The molded product of Example 4 has a box shape in which a gentle curved surface of 100 mm × 50 mm and a flat surface are combined, and a 40 mm × 20 mm hole (opening portion) is provided in order to arrange a small liquid crystal display device at the center. ) Is vacant, the wall thickness is 1.5 mm, and the outer edge has a box-shaped (concave) shape with a side wall having a height of 8 mm. The reflectance was measured at a flat portion.

The mold assembly 10 of Example 4 is similar to the conceptual diagram shown in FIG.
(A) a first mold part (fixed mold part) 11, a second mold part (movable mold part) 12, and a molten resin injection part 14 provided in the first mold part 11, A mold in which a cavity 13 is formed by clamping the first mold part 11 and the second mold part 12, and
(B) Nests 20 </ b> A and 20 </ b> B that are arranged in the first mold part 11 and the second mold part 12 and form a surface constituting the cavity 13,
It has. The molten resin injection part 14 has a side gate structure with one gate point, as in the first embodiment. And the die assembly of Example 4 is further as shown in FIG.
(C) Metal films 40A and 40B having a thickness of 0.03 mm to 0.5 mm disposed on the surface of the insert, forming a surface constituting the cavity 13;
It has.

Then, as shown in FIG. 4 and a schematic partial sectional view enlarged in FIG. 1C, the nestings 20A and 20B are similar to the first embodiment.
(A) Metal blocks 31A, 31B,
(B) metal underlayers 32A and 32B having a thickness of 0.03 mm to 1 mm formed on at least the surfaces of the metal blocks 31A and 31B facing the cavity 13 (the top surfaces of the metal blocks 31A and 31B), and
(C) Thermal spray coatings 33A and 33B made of ceramics formed on the metal base layers 32A and 32B,
It is composed of The inserts 20A and 20B are fixed to the first mold part (fixed mold part) 11 and the second mold part (movable mold part) 12 using bolts (not shown).

  The thermal spray coatings 33A and 33B have the porosity changed in the thickness direction in the same manner as in Example 1. The porosity is closer to the surface of the thermal spray coatings 33A and 33B (the surface of the thermal spray coatings 33A and 33B). The closer the part is, the lower the value.

  Here, in Example 4, in the inserts 20A and 20B for forming a molded product, the shape of the insert 20A arranged in the first mold part 11 is a “concave” shape, and the outer dimensions ( (Length × width × thickness) is 120 mm × 70 mm × 40 mm, and the dimension length × width × depth of the portion (concave portion) of the insert 20A for molding the outer surface of the molded product is 100 mm × 50 mm × 8 mm. On the other hand, the shape of the insert 20B arranged in the second mold part 12 is a “convex” shape, and the outer dimensions (length × width × thickness) are 97 mm × 47 mm × 6.5 mm. Furthermore, it has a gentle curvature of about 1000 mm as a whole, and a curvature having a diameter of 3.0 mm is given to the outer surface side in the boundary region (corner portion) with the side wall. In order to form a hole (opening), a 40 mm × 20 mm metal core is provided near the center.

In Example 4, the thermal spray coatings 33A and 33B are formed of one unit layer (consisting of ZrO ₂ ) as shown in the enlarged schematic partial sectional view of the nesting 20A and 20B in FIG. And is formed by a plasma spraying apparatus. Specifically, the sprayed coatings 33A and 33B are made of ZrO ₂ . The surfaces of the sprayed coatings 33A and 33B have a mirror finish. The surface roughness (maximum height of the contour curve) R _z of the surface of the thermal spray coatings 33A and 33B is 0.13 μm. Here, as shown in FIG. 4, metal films 40A and 40B are disposed on the surface of the second layer (upper layer) 33 ″. Specifically, the second layer (upper layer) 33 ″. After etching the surface of the film with an acid, metal films 40A and 40B made of Ni-P and having a thickness of 100 μm are formed on the surface of the second layer (upper layer) 33 ″ by electroless plating, Thus, the metal films 40A and 40B having a surface roughness (maximum height of the contour curve) R _z of 0.05 μm and a thickness of 80 μm after the mirror finish can be obtained.

  Table 6 shows the composition and thickness of the metal underlayer in Example 4 or Example 5 to be described later; the composition, layer configuration, total thickness, and thermal conductivity of the entire thermal spray coatings 33A and 33B; thermal spray coatings 33A and 33B. Composition, thickness, porosity average value, average particle diameter, surface roughness of the second layer (upper layer) unit layer 33 ″ or the thermal spray coatings 33A, 33B constituting the first layer constituting the thermal spray coatings 33A, 33B The composition (thickness), porosity average value, average particle size of the layer (lower layer) unit layer 33 ′; the average porosity of the surface region, the average particle size; the average porosity of the bottom region, and the average particle size are shown. .

  For comparison, Table 7 shows the composition and thickness of the metal underlayer in Comparative Example 4A, Comparative Example 4B, and Comparative Example 4C; the composition of the entire sprayed coating, the layer configuration, the total thickness, and the thermal conductivity; Composition, thickness, porosity average value, average particle size, surface roughness of the second layer (upper layer) unit layer or thermal spray coating; composition of the first layer (lower layer) unit layer constituting the thermal spray coating, Thickness, average porosity, average particle size; average porosity of surface region, average particle size; average porosity, average particle size of bottom region.

  Here, in Comparative Example 4A, Comparative Example 4B, and Comparative Example 4C, the metal underlayer is not formed. In Comparative Example 4A, the thermal spray coating is composed of two unit layers having different compositions. In Comparative Example 4B, the thermal spray coating is composed of two unit layers having the same composition. In Comparative Example 4C, the thermal spray coating is composed of a single-layer thermal spray coating. In Comparative Example 4C, the thermal spray coating was formed so that the porosity value of the entire one thermal spray coating was the same.

[Table 6]

[Table 7]

  Table 8 shows the injection molding conditions in Example 4. In addition, in Example 4-6, as an injection molding machine, Tomo Heavy Industries Industry Co., Ltd. SG75 was used. In the fourth embodiment, the first mold part (fixed mold part) 11 and the second mold part (movable mold part) are similar to the conceptual diagram of the mold assembly 10A shown in FIG. ) 12 is clamped to form the cavity 13. The resin composition (Composition-E) is plasticized, melted and weighed in the injection cylinder 16 and then passed from the injection cylinder 16 through the runner part and sprue part 15 and the molten resin injection part (gate part) 14. The molten resin composition was injected into the cavity 13 under the injection molding conditions shown in Table 8, and the cavity 13 was completely filled with the molten resin composition. Next, the resin composition in the cavity 13 was cooled and solidified, and then the obtained molded product was released from the mold.

  The evaluation results of the molded product of Example 4 are shown in Table 8. Even in Example 4, although it was the molten resin injection part 14 having a side gate structure with one gate point, the molded product has very good transferability, no weld line is generated, It had high gloss and deep jetness. Further, the molded product was free from warpage and was very luxurious. Further, although molding was performed 50,000 times, no damage or the like occurred in the inserts 20A and 20B.

  For comparison, when injection molding was performed using a insert made of steel, the cavity 13 could not be completely filled with the molten resin composition (Composition-E). Therefore, when the resin temperature was changed to 310 ° C. and the mold temperature was changed to 120 ° C. and injection molding was performed, the cavity 13 could be completely filled with the molten resin composition. A weld line was generated, and a flow mark was generated around the weld line and in the vicinity of the molten resin injection portion 14, the appearance of the molded product was very ugly, and a jet black feeling was not obtained in the molded product. Moreover, since the resin composition is forcibly filled into the cavity 13, the molded product is warped. Such a comparative example is referred to as Comparative Example 4D.

  When the surface of the thermal spray coating obtained by Example 4 or Example 5 to Example 6 described later was visually observed, it had high gloss, the surface was smooth, and cracks were observed. There wasn't. On the other hand, in Comparative Example 4A, the surface of the sprayed coating was rough and the surface roughness was very rough. Moreover, when the surface of the thermal spray coating obtained by Comparative Example 4B was visually observed, cracks were generated. Furthermore, when the surface of the thermal spray coating obtained in Comparative Example 4C was visually observed, large irregularities were observed on the surface. In addition, the sample obtained in the comparative example was also peeled off at the interface with the metal block. Table 8 shows the evaluation results of the molded products obtained in Comparative Example 4A, Comparative Example 4B, and Comparative Example 4C.

  Example 5 is a modification of Example 4 and relates to the injection molding method according to the second aspect of the present invention. In order to mold a molded product having a hollow portion, a gas assist molding method was employed.

  In the fifth embodiment, the mold used in the fourth embodiment is used so that the sink marks in the portion of the molded product facing the insert 20A arranged in the first mold portion 11 can be further reduced as compared with the fourth embodiment. A recess is provided on the outer peripheral portion of the insert 20B arranged in the second mold portion 12 so that a rib portion having a thickness of 6 mm is formed in a portion of the molded product facing the outer peripheral portion.

  Further, in order to form a hollow portion in the rib portion, similarly to the mold assembly described in the second embodiment, the second mold portion (movable mold portion) 12 and piping for introducing pressurized fluid are added. A pressurized fluid injection nozzle 17 and a moving means 18 were installed.

  Table 8 shows the injection molding conditions in Example 5. Also in the fifth embodiment, a conceptual diagram of the mold assembly 10B is shown in FIG. 3, and as described in the third embodiment, the first mold portion (fixed mold portion) 11 and the second mold portion. The cavity 13 is formed by clamping the (movable mold part) 12. Then, the pressurized fluid injection nozzle 17 was moved in the direction toward the cavity 13 by the operation of the moving means 18 and positioned at the forward end (see FIG. 3). In this state, the pressurized fluid injection nozzle 17 communicates with the cavity 13. The resin composition (Composition-F) is plasticized, melted and weighed in the injection cylinder 16, and then from the injection cylinder 16 through the runner part and the sprue part 15 and the molten resin injection part (gate part) 14. The molten resin composition was injected into the cavity 13 under the injection molding conditions shown in Table 8, and a part of the cavity 13 was filled with the molten resin composition. In Example 5, a molten resin composition having a capacity satisfying about 99% of the cavity volume was injected into the cavity 13. Immediately after the completion of injection, 150 MPa of nitrogen gas was injected into the molten resin composition in the cavity 13 from the pressurized fluid injection nozzle 17. Next, the resin composition in the cavity 13 was cooled and solidified, and then the obtained molded product was released from the mold. Even in Example 5, the mold was not provided with an overflow cavity communicating with the cavity 13, but an overflow cavity structure in which a part of the molten resin composition injected into the cavity 13 can flow during molding. Can be used. In this case, since a part of the molten resin composition injected into the cavity 13 flows into the overflow cavity, it becomes easier to form a hollow portion.

  The evaluation results of the molded product of Example 5 are shown in Table 8. Since the gas-assisted molding method was adopted, no sink marks were observed on the outer periphery of the molded product, and the transferability was excellent, so it had very high gloss and deep jetness. Further, similarly to Example 4, there was no occurrence of a weld line generated when the molten resin compositions were joined together, and no “color unevenness” phenomenon, which was a phenomenon peculiar to gas assist molding. Further, although molding was performed 50,000 times, no damage or the like occurred in the inserts 20A and 20B.

  For comparison, when injection molding was performed using a nest made of steel, the cavity 13 could not be completely filled with the molten resin composition (Composition-F), and nitrogen gas was introduced into the cavity 13. When injected into the molten resin composition, the resulting molded product had holes as defective portions. Therefore, when the injection pressure was changed to 150 MPa and gas assist molding was performed, the molten resin composition could be completely filled into the cavity 13, and a hole as a defective portion was opened in the obtained molded product. Although it was not, glossiness and deep jetness were worse than in Example 5, and a weld line was generated around the confluence of the resin near the metal core. It was generated, and it was not possible to obtain a casing having an excellent appearance. Such a comparative example is referred to as Comparative Example 5A, and the evaluation results of the molded product are shown in Table 8. Further, as a polycarbonate resin composition, a molded product obtained by injection molding under the same injection molding conditions as in Comparative Example 5A using Composition-H is shown as Comparative Example 5B. It is shown in FIG.

  In Example 6, using the mold assembly described in Example 4, and using the composition-G shown in Table 2, based on the same injection molding conditions as in Example 4, the same shape as in Example 4 The molded product was obtained. The evaluation results of the molded product are shown in Table 8. The molded product was very excellent in transferability, had no weld line, and had very high gloss and deep jetness.

[Table 8]

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The structure and configuration of the nesting described in the examples, the material used, the configuration and structure of the mold assembly, the injection molding conditions, and the like are examples, and can be changed as appropriate. In the embodiment, the nest is disposed in the first mold part and the second mold part. However, depending on the molded product to be molded, the nest may be disposed only in the first mold part. The nest may be provided only in the second mold part. Depending on the molded product to be molded, the entire surface of the nesting facing the cavity can be made of a sprayed coating, or a part of the surface can be made of a sprayed coating, Can be configured such that the metal block is exposed. In the embodiment, the nestings 20A and 20B have the same configuration, but may have different configurations as necessary. Moreover, you may arrange | position a metal film on the surface only in a part of nesting.

1A is a schematic cross-sectional view of a nesting in Example 1, and FIGS. 1B and 1C are schematic partial cross-sectional views in which the nesting is enlarged. FIG. 2 is a conceptual diagram of the mold assembly according to the first embodiment. FIG. 3 is a conceptual diagram of the mold assembly according to the second embodiment. FIG. 4A is a schematic cross-sectional view of the nesting in the fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Mold assembly, 11 ... 1st mold part (fixed mold part), 12 ... 2nd mold part (movable mold part), 13 ... Cavity, 14 ... -Molten resin injection part (gate part), 15 ... runner part and sprue part, 16 ... injection cylinder, 17 ... pressurized fluid injection nozzle, 18 ... moving means, 20A, 20B ... -Nesting, 31A, 31B ... Metal block, 32A, 32B ... Metal base layer, 33A, 33B ... Thermal spray coating, 33 ', 33 "... Unit layer, 40A, 40B ... Metal film

Claims (15)

(A) A first mold part, a second mold part, and a molten resin injection part provided in the first mold part, and a cavity formed by clamping the first mold part and the second mold part. A mold in which is formed, and
(B) Nesting arranged in the first mold part and / or the second mold part,
With
Nesting is
(A) metal block,
(B) a metal underlayer having a thickness of 0.03 mm to 1 mm formed on at least the surface of the metal block facing the cavity; and
(C) a thermal spray coating made of ceramics formed on a metal underlayer;
Consists of
The thermal spray coating has a porosity that varies in the thickness direction,
The porosity is a molded product made of a polycarbonate resin composition formed by using a mold assembly having a lower value on the side closer to the sprayed coating surface,
The maximum height R _z of the contour curve is 0.2 μm or less, the average length RSm of the contour curve element is 25 μm or less, and the reflectance at 400 nm to 650 nm measured by a spectrophotometer is 0.7%. A molded article made of a polycarbonate resin composition, characterized by: (C) a metal film having a thickness of 0.03 mm to 0.5 mm disposed on the surface of the nest, forming a surface constituting the cavity;
The molded product made of the polycarbonate resin composition according to claim 1, wherein the molded product is molded using a mold assembly further comprising:   3. A molded article made of a polycarbonate resin composition according to claim 1, wherein a sprayed coating is formed on the entire surface of the metal block facing the cavity.   The molded product made of a polycarbonate resin composition according to claim 1 or 2, wherein a sprayed coating is formed on a part of the surface of the metal block facing the cavity. The thermal conductivity of the thermal spray coating is 1 W / (m · K) to 4 W / (m · K),
The molded article made of a polycarbonate resin composition according to any one of claims 1 to 4, wherein an average thickness of the thermal spray coating is 0.3 mm to 2.0 mm.   The average porosity of the portion from the surface of the thermal spray coating to the thickness of 0.05 mm toward the inside of the thermal spray coating is 0.4% or more and less than 5%, and it goes from the interface between the metal underlayer and the thermal spray coating to the inside of the thermal spray coating. 6. The molding made of a polycarbonate resin composition according to claim 1, wherein an average porosity value in a portion up to 0.2 mm thick is 5% or more and 10% or less. Goods. The average particle size of the material constituting the thermal spray coating in the portion from the thermal spray coating surface to the thickness of 0.05 mm toward the inside of the thermal spray coating is 2 × 10 ⁻⁶ m to 5 × 10 ⁻⁵ m. The average particle diameter of the material constituting the thermal spray coating in the portion from the interface with the thermal spray coating to the thickness of 0.2 mm toward the inside of the thermal spray coating is 2 × 10 ⁻⁵ m to 1 × 10 ⁻⁴ m. A molded product made of the polycarbonate resin composition according to any one of claims 1 to 5.   3. The molding made of the polycarbonate resin composition according to claim 2, wherein the metal film is made of at least one material selected from the group consisting of chromium, a chromium compound, nickel, and a nickel compound. Goods.   The molded article made of a polycarbonate resin composition according to claim 8, wherein the metal film is formed on the thermal spray coating by plating. The molded product made of a polycarbonate resin composition according to claim 2, wherein the maximum height R _z of the contour curve of the surface of the metal film is 0.03 µm or less, and the surface of the metal film is flat.   A colorant comprising a combination of two or more dyes, or a carbon nanotube, or a colorant comprising a combination of two or more dyes and a polycarbonate resin composition obtained by adding carbon nanotubes to a polycarbonate resin. A molded article made of the polycarbonate resin composition according to any one of claims 1 to 10. The maximum height R _z of the contour curve is 0.2 μm or less, the average length RSm of the contour curve element is 25 μm or less, and the reflectance at 400 nm to 650 nm measured by a spectrophotometer is 0.7%. An injection molding method for a molded article made of a polycarbonate resin composition, which is:
(A) A first mold part, a second mold part, and a molten resin injection part provided in the first mold part, and a cavity formed by clamping the first mold part and the second mold part. A mold in which is formed, and
(B) Nesting arranged in the first mold part and / or the second mold part,
With
Nesting is
(A) metal block,
(B) a metal underlayer having a thickness of 0.03 mm to 1 mm formed on at least the surface of the metal block facing the cavity; and
(C) a thermal spray coating made of ceramics formed on a metal underlayer;
Consists of
The thermal spray coating has a porosity that varies in the thickness direction,
The porosity is an injection molding method using a mold assembly that has a lower value on the side closer to the sprayed coating surface,
(A) After forming the cavity by clamping the first mold part and the second mold part, the molten polycarbonate resin composition is injected into the cavity from the molten resin injection part,
(B) The polycarbonate resin composition in the cavity is cooled and solidified, and then the obtained molded product is released from the mold.
An injection molding method comprising the steps. (C) a metal film having a thickness of 0.03 mm to 0.5 mm disposed on the surface of the nest, forming a surface constituting the cavity;
The injection molding method according to claim 12, wherein a mold assembly further comprising: is used. Using a mold assembly further comprising a pressurized fluid injection nozzle in communication with the cavity,
In the step (a), the molten polycarbonate resin composition is injected into the cavity from the molten resin injection portion, simultaneously with the completion of the injection, or after the injection is completed, in the molten polycarbonate resin composition injected into the cavity. 14. The injection molding method according to claim 12, wherein injection of a pressurized fluid is started from a pressurized fluid injection nozzle.   The polycarbonate resin composition is a colorant composed of a combination of two or more dyes, or a carbon nanotube, or a polycarbonate resin composition obtained by adding a colorant composed of a combination of two or more dyes and carbon nanotubes to the polycarbonate resin. The injection molding method according to any one of claims 12 to 14, wherein the injection molding method is performed.

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