JPH09155876A - Heat insulating mold and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart the excellent resistance to a cooling and heating cycle or to shear stress at a time of molding by strongly and closely bonding a metal layer to the surface of a heat insulating layer by providing the heat insulating layer having an etching aid specified in a particle size dispersed therein to the cavity wall surface of a mold and applying plating thereto after etching. SOLUTION: A heat insulating layer composed of a heat-resistant polymer having an etching aid with an average particle size of 1-50nm added to the upper layer thereof in a state dispersed within a range of 1-50vol.% is provided to the mold cavity wall surface of a main mold composed of metal and plating is applied thereto after etching to form a metal layer. The heat-resistant polymer used in the heat insulating layer is a thermoplastic polymer having a softening temp. higher than the molding temp. of a synthetic resin to be molded or a cured physical property resin having heat resistance higher than the molding temp. and pref. a polymer having a softening temp. higher than the molding temp. of the synthetic resin to be molded and a glass transition temp. of 140 deg.C or higher.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating mold for molding synthetic resin and a method for manufacturing the same. More specifically, the present invention relates to a heat insulating mold having excellent moldability in various molding applications such as injection molding and blow molding of synthetic resin, and also excellent in durability against shear stress due to the resin at the time of molding and a heat cycle, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for omitting post-processing such as coating on synthetic resin injection molded products and blow molded products. There is a strong hope that the coating will be eliminated in order to reduce manufacturing costs and reduce environmental damage due to solvent evaporation during painting. There is a particularly strong demand for omitting post-processing of electrical resin, electronic equipment, synthetic resin housings of office equipment, and the like.

In order to improve the reproducibility of the mold surface state and the appearance of the molded product, a thermoplastic resin is injected into a mold cavity to increase the resin temperature and the mold temperature, and the injection pressure is increased. Corresponding to molding conditions such as is usually selected. Similarly, in blow molding, to improve the appearance of the molded product,
It is usually selected to take measures depending on the molding conditions such as increasing the resin temperature and the mold temperature and increasing the blow gas pressure.

Among these factors, the mold temperature has a particularly great influence. Higher mold temperatures can improve these performances. However, when the mold temperature is increased, the time required for cooling and solidifying the plasticized resin becomes long, and the molding efficiency is generally lowered. Therefore, there is a strong demand for a method of improving the reproducibility of the mold surface without increasing the mold temperature, or a method of not prolonging the cooling time even if the mold temperature is increased.

For example, a method in which heating and cooling holes are attached to a mold and heating and cooling of the mold are repeated by alternately flowing a heat medium and a cooling medium is a method of Plastic / Tech.
No., June, 151 (1988) [Plastic Technology, June, 151 (1988)] and the like, but this method consumes a large amount of heat energy and the molding efficiency is not sufficiently increased.

A mold in which a mold wall forming a mold cavity is covered with a heat insulating layer having a small thermal conductivity, that is, a heat insulating mold is disclosed in WO 93/06980 and the like. When the surface of the mold is covered with a heat insulating layer, when the heated resin injected onto the surface comes into contact with the heat insulating layer, the mold surface receives the heat of the resin and the temperature rises. The smaller the thermal conductivity of the heat insulating layer and the thicker the heat insulating layer, the higher the mold surface temperature, and the moldability can be improved. However, the mold having the outermost surface of the polymer as the heat insulating layer, that is, the heat insulating mold having only the main mold and the heat insulating layer can improve moldability, but the heat insulating layer is easily scratched during use. Further, depending on the type of synthetic resin to be molded, there is a problem that it becomes difficult to release the mold surface from the heat insulating layer during molding.

As a method for improving this, Japanese Patent Laid-Open No. 53-8675.
No. 4 discloses a heat insulating mold in which a wall surface of a metal mold is covered with a heat insulating layer and the surface of the heat insulating layer is covered with a thin metal layer, that is, a heat insulating mold including a main mold, a heat insulating layer and a metal layer. It has already been disclosed.

[0008]

We have found that the mold having the surface of the heat insulating layer further covered with a thin metal layer has the following problems. That is, when the metal layer of the heat insulating mold is thick, the reproducibility of the mold surface is deteriorated, and when it is thin, the mold surface is easily scratched. When the thickness of the heat insulating layer of the heat insulating mold is increased, the molding time cycle becomes longer and the molding efficiency is lowered, and when the thickness is reduced, the effect of improving the moldability is lowered. The required heat insulation layer thickness and metal layer thickness are closely related to the softening temperature of the synthetic resin to be molded, molding conditions, etc., and the optimum heat insulation mold structures are different. The metal layer and the heat insulating layer are required to have high durability such that they are easily peeled off due to a cold heat cycle or shear stress during molding and firmly adhered to each other. It was discovered that there are problems to be solved as described above.

[0009]

SUMMARY OF THE INVENTION The present invention aims to solve these problems. That is, the present invention is as follows. (1) From a heat-resistant polymer containing an etching aid having an average particle diameter of 1 to 500 nm dispersed in at least an upper layer in an amount of 1 to 50% by volume on a mold cavity wall surface of a main mold made of a metal. A heat-insulating layer is provided, and a method for producing a heat-insulating mold composed of a main mold, a heat-insulating layer and a metal layer obtained by forming a metal layer by plating after etching (2) The etching aid is an inorganic filler And (3) the method for producing the heat insulating mold of (1), wherein the etching aid is a metal oxide obtained by a gas phase reaction method (4) the method for producing the heat insulating mold (4) Said auxiliaries are selected from aluminum oxide, titanium oxide, zirconium oxide, antimony oxide, chromium oxide, ferric oxide, germanium oxide, vanadium oxide and tungsten oxide. (1) or (3) method for manufacturing heat insulating mold (5) Etching aid is titanium oxide, (4) Method for manufacturing heat insulating mold (6) Etching aid is aluminum oxide (4) Manufacturing method of heat insulating mold according to (4) (7) Manufacturing method of heat insulating mold according to (1) to (6), wherein the heat-resistant polymer is polyimide (8) Metal layer (1) to (7), characterized in that the chemical and / or electroless nickel plating layer is included.
(9) Heat-insulating mold obtained by the above-mentioned manufacturing methods (1) to (8) (10) The thickness of the heat-insulating layer is in the range of 0.05 to 3 mm, and the thickness of the metal layer is 1 to 300 μm. Insulation mold according to the above (9), characterized in that the thickness is within a range and is 1/3 or less of the thickness of the heat insulation layer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The main mold forming the heat insulating mold of the present invention is iron or a steel material containing iron as a main component, aluminum,
Alternatively, it is selected from a range that broadly includes a mold made of a metal generally used for molding a synthetic resin such as an alloy containing aluminum as a main component, a zinc alloy such as ZAS, and a beryllium-copper alloy. In particular, a die made of steel is inexpensive and can be used favorably. It is preferable that the surface of the mold in contact with the heat insulating layer of the main mold made of these metals is plated with hard chromium, nickel, or the like. The shape of the main mold differs depending on the target molded body and is not particularly limited.

In the method of manufacturing the heat insulating mold of the present invention, first, the average particle size is 1 to 50 on the wall surface of the mold cavity of the main mold.
An etching aid in the range of 0 nm is applied to at least the upper layer as 1
A heat insulating layer composed of a heat resistant polymer dispersedly contained in the range of ˜50% by volume is provided. The heat insulating layer in the present invention is a generic term for a layer formed of a heat resistant polymer alone and a layer formed of a heat resistant polymer in which an etching aid is dispersed.

The heat resistant polymer used in the heat insulating layer in the present invention is a thermoplastic polymer having a softening temperature higher than the molding temperature of the synthetic resin to be molded, or a curable resin having a heat resistance higher than the molding temperature. . Preferably, the softening temperature is higher than the molding temperature of the molded synthetic resin, and the glass transition temperature is preferably 140 ° C. or higher, more preferably 160 ° C. or higher, most preferably 190 ° C. or higher, and / or the melting point is preferably 200. ℃ or more, more preferably 250 ℃
It is the above polymer.

The softening temperature of a synthetic resin is a temperature at which the synthetic resin can be easily deformed. Vicat softening temperature (ASTM D1525) for amorphous resin, heat distortion temperature (ASTM D648, load 18.6 kg / c) for hard crystalline resin.
m ² ), the heat distortion temperature (ASTM ・ D
648 and a load of 4.6 kg / cm ² ) respectively. The hard crystalline resin is, for example, polyoxymethylene, nylon 6, nylon 66, and the like, and the soft crystalline resin is, for example, various polyethylenes, polypropylenes, and the like.

Further, the elongation at break of the heat resistant polymer is preferably 4% or more, more preferably 5% or more, particularly preferably 10% or more, and a polymer having high elasticity and elongation and high toughness is preferable. . The measuring method for breaking elongation is ASTM D6
The tensile speed at the time of measurement is 5 mm / min.

The heat-resistant polymer which can be used as the heat insulating layer of the present invention can be widely selected from the heat-resistant polymers having the above-mentioned softening temperature, but a particularly preferable heat-resistant polymer is a heat-resistant polymer having an aromatic ring in its main chain. It is a polymer. Various aromatic non-crystalline or crystalline heat resistant polymers such as polyimide, aromatic heterocyclic polymers, epoxy resins and polysulfones can be favorably used.

As the polyimide, various linear non-thermoplastic polyimide resins, linear thermoplastic polyimide resins and resin thermosetting polyimide resins can be widely used. As the linear non-thermoplastic polyimide resin, for example, polypyromellitic imide type, polyphenyl tetracarboxylic imide type,
Examples include polybenzophenone tetracarboxylic imide type, polyamide imide, and polyether imide, and linear type thermoplastic polyimide resins include polybenzophenone tetracarboxylic imide type and polybiphenyl tetracarboxylic imide type, resin thermosetting polyimide. Examples of the resin include bismaleimide-based resin, nadic modified polyimide, Diels-Alder type polyimide, and the like. Generally, linear high-molecular-weight polyimide has large elongation at break and is tough and has excellent durability, and fluorine-containing polyimide has moisture resistance (moisture resistance of the heat insulation layer is improved, and the amount of water remaining when the heat insulation mold is heated is low. It is excellent in that the peeling of the plating due to the foaming of water is suppressed) and the like, and it can be preferably used in some cases. Generally, linear high molecular weight polyimide has a large elongation at break and is tough.
It has excellent durability and can be used particularly well.

Examples of aromatic heterocyclic polymers include polybenzazoles (eg polybenzimidazole, polybenzoxazole, polybenzothiazole, polyetherbenzoxazole), polyhydantoins (eg polyimidazolidine-2,4-dione) and Examples thereof include polyparabanic acids (for example, polyimidazolidine-2,4,5-trione).

The epoxy resin can be selected from a wide variety of resins. For example, bis-A type epoxy resin, brominated epoxy resin, bisphenol F type epoxy resin,
Novolac type epoxy resin, cycloaliphatic epoxy resin,
Examples thereof include triglycidyl isocyanate-based resins.

Examples of the polysulfone-based resin include polysulfone, polyether sulfone, polyarylene sulfone and the like.

Table 1 shows the structure and glass transition temperature (Tg) of the heat resistant polymer which can be favorably used in the present invention.

[0021]

[Table 1]

These heat-resistant polymers can be mixed with known fillers such as various fillers and fillers such as inorganic fibers in order to improve the resistance to the cold cycle during molding, and the thermal expansion coefficient can be lowered. The heat resistant polymer having a reduced coefficient of thermal expansion can be preferably used as a heat insulating layer in some cases.

Examples of preferred fillers include powders and particles of glass, silica, talc, clay, zirconium silicate, lithium silicate, calcium carbonate, alumina, mica, and the like, and examples of inorganic fibers include glass fibers, whiskers, Carbon fiber may be used.

In addition to these heat resistant polymers, other tough resins,
Alternatively, a resin in which various compounds such as rubber that improve the toughness are mixed can be favorably used. For example, a polymer alloy obtained by blending an epoxy resin with nylon or polyimide and curing has excellent toughness and can be suitably used in some cases. Further, an epoxy resin having a small coefficient of thermal expansion, that is, an epoxy resin cured product obtained by combining an epoxy resin having a small coefficient of thermal expansion and a curing agent, or an epoxy resin containing various fillers in an appropriate amount can be preferably used.

Since the epoxy resin generally has a large coefficient of thermal expansion, the difference in the coefficient of thermal expansion from that of the metal mold is large, and the epoxy resin is apt to be deteriorated by the cooling / heating cycle. Therefore, a filler-containing epoxy resin in which an appropriate amount of a filler such as various fillers or inorganic fibers having a small coefficient of thermal expansion is mixed with the epoxy resin to reduce the difference in the coefficient of thermal expansion with the metal mold is a heat insulating material of the present invention. It can be used well as a layer.

In injection molding, blow molding, etc., the mold surface that comes into contact with the heated resin to be molded is exposed to a strict cooling / heating cycle for each molding. The metal layer formed on the surface of the heat insulating layer by plating generally has a smaller coefficient of thermal expansion than the heat insulating layer made of a polymer, and the coefficient of thermal expansion of the heat insulating layer and the metal layer is significantly different, so the stress at the interface repeats every molding. Occurs and peeling easily occurs at the interface. Main mold and / or in contact with heat insulation layer
Alternatively, by reducing the difference between the coefficient of thermal expansion of the metal layer and the coefficient of thermal expansion of the heat insulating layer, the stress that causes peeling can be reduced.

The cause of peeling between the heat insulating layer and the main mold or between the heat insulating layer and the metal layer is not only the difference in the coefficient of thermal expansion, but the difference in the coefficient of thermal expansion is a major factor. The adhesion between the heat insulation layer and the main mold and the metal layer is large, and the elastic modulus is small,
With a heat insulating layer made of a soft material having a large breaking elongation, peeling does not occur even if the difference in the coefficient of thermal expansion is slightly large. However, a material suitable for the heat insulating layer, that is, a heat insulating material having a high heat resistance, a high hardness, and a mirror surface by polishing, has a large elastic modulus in general. Particularly, a heat-resistant hard synthetic resin having an aromatic ring in the main chain is applicable. Therefore, in order to bring the heat-resistant synthetic resin layer into close contact with the main mold and the metal layer so as not to cause peeling, a small difference in thermal expansion coefficient is required.

In the heat insulating mold of the present invention, the difference between the coefficient of thermal expansion of the main mold and / or the metal layer in contact with the heat insulating layer and the coefficient of thermal expansion of the heat insulating layer is less than 4 × 10 ^-5 / ° C. Is preferable from the viewpoint of resistance to cooling / heating cycles during molding, and more preferably less than 3 × 10 ⁻⁵ / ° C. Generally, metals have a smaller coefficient of thermal expansion than polymers. Therefore, it is preferable to select a heat-resistant polymer having a small coefficient of thermal expansion.

The coefficient of thermal expansion described here is a coefficient of linear expansion. The thermal expansion coefficient of the heat insulating layer is the coefficient of linear expansion in the surface direction of the heat insulating layer, and is measured by the method shown in JIS K7197-1991, and is the average value between the temperatures of 50 ° C and 250 ° C, or the glass transition of the heat insulating layer. If the temperature is below 250 ° C,
It is shown as an average value between 50 ° C. and the glass transition temperature. That is, a heat insulating layer is formed on a flat metal plate, and then the heat insulating layer is peeled off, and the average thermal expansion coefficient of the heat insulating layer between 50 ° C. and 250 ° C. or between 50 ° C. and the glass transition temperature. Is measured.

A metal of the main mold which can be favorably used in the present invention,
Table 2 shows the coefficients of thermal expansion of the metal of the metal layer coated on the outermost surface, the heat-resistant polymer of the heat insulating layer, and the general synthetic resin.

[0031]

[Table 2]

* By adding carbon fiber to these resins, the coefficient of thermal expansion can be lowered to around 4 × 10 ⁻⁵ / ° C.

If the coefficient of thermal expansion of the main mold and / or the metal layer is increased, a heat insulating layer having a relatively large coefficient of thermal expansion can be used. Steel is most often used as the mold material, but recently aluminum alloys and zinc alloys have also been used. In the present invention, the closer the coefficient of thermal expansion is, the more preferable. When steel is used for the main mold, low thermal expansion type polyimide having a very small thermal expansion coefficient can be used particularly well.

In order to coat the surface of the main mold with the heat resistant polymer and firmly adhere it, a sheet of the heat resistant polymer is attached or a powder of the heat resistant polymer is sprayed and melt-bonded. You can also Depending on the kind of heat resistant polymer, a vapor deposition polymerization method on a metal surface, a coating method of a heat resistant polymer solution or a spray method can be preferably used. The vapor deposition polymerization method basically evaporates a monomer (an acid dianhydride and a diamine) under reduced pressure to deposit and polymerize on a metal surface, and is an excellent method in that it can be applied to adhesion and a complicated shape. For example, [Book Name: Polyimide Resin 299 (1991), Publisher: Technical Information Society] has a detailed description of this method.
The coating method or spraying method is a method of forming a heat-insulating layer of a heat-resistant polymer by applying or spraying a heat-resistant polymer solution, a heat-resistant polymer precursor solution or a liquid precursor, and then heat drying or curing. It can be practically used particularly preferably. In this method, the heat-resistant polymer or the precursor of the heat-resistant polymer to be used is preferably soluble in a solvent or in a liquid state. For example, a method of forming a polyimide on the mold wall surface by applying a solution of a polyamic acid which is a precursor of polyimide, followed by drying and heat curing can be favorably used.

When a solution of polyimide or its precursor is applied or sprayed to form a heat insulating layer, it may foam during heating or drying due to volatilization of the solvent or volatilization of water generated by the imidization reaction. In order to avoid this, it is preferable to gradually dry and cure at a temperature not higher than the foaming temperature, or to divide thinly and repeatedly apply thin coating-heat drying or curing. When it is repeatedly applied, if the imidization is completed in each step, the heat insulating layer may be easily peeled off. In such a case, the imidation ratio in each step is generally less than 90%, preferably less than 75%, particularly preferably less than 60%. After coating all layers, heating to a high temperature completes the imidization. Although any coating method may be used, spray coating can be preferably used in view of workability in terms of uniform coating.

Temperature, time for heat drying or curing,
Atmospheric conditions are also important. For example, when a polyimide precursor polyamic acid solution is applied to a mold wall surface and then subjected to heating curing (curing) to form a polyimide, the heating curing temperature and the heating curing atmosphere allow the polyimide performance, particularly the glass transition temperature, the heat Decomposition temperature or coefficient of thermal expansion is different. Generally, the higher the heating and curing temperature, the higher the glass transition temperature and the smaller the thermal expansion coefficient, which is preferable. However, there is a problem that extremely high curing temperature causes deterioration of the polyimide and distortion of the main mold. Generally, polyamic acid is imidized to about 10 when heated to 250 ° C. or higher.
Progressing 0%, polyimide is formed. The atmosphere during heating depends on the polymer characteristics and heating conditions, but in order to avoid deterioration of the polymer and the like, it may be preferable to carry out in an atmosphere with little water content, in the absence of oxygen, or in nitrogen.

The thermal conductivity of these heat resistant polymers is generally 0.0001 to 0.002 cal / cm · sec · ° C.
And, it is much smaller than metal and works effectively as a heat insulating layer.
When the filler is mixed with the heat resistant polymer, a large amount of the inorganic filler or the filler having a relatively high thermal conductivity increases the thermal conductivity of the heat insulating layer, and thus the heat insulating layer of the same heat conductivity. There is a case where the heat capacity is increased, which is not preferable. When a composition in which a filler such as an inorganic filler is mixed is used, its thermal conductivity is preferably 0.01 cal / cm · sec.
-° C, more preferably 0.005 cal / cm-se
c · ° C., particularly preferably 0.002 cal / cm · se
Keep below c ・ ° C.

In the heat insulation mold of the present invention, it is necessary that the adhesion between the heat insulation layer and the main mold and the adhesion between the heat insulation layer and the metal layer are sufficiently large. Specifically, it is preferable that peeling does not occur due to shear stress or cooling and heating cycles caused by molding the synthetic resin more than 10,000 times. To achieve this, the adhesion between the heat insulation layer and the main mold, and the adhesion between the heat insulation layer and the metal layer have a peel strength of 0.5 kg / 10 mm at room temperature.
The width is preferably not less than 0.8, more preferably 0.8.
More than kg / 10mm width, most preferably 1kg / 10m
m width or more. This is done by cutting the adhered metal layer, or the metal layer and the heat insulation layer into 10 mm width, and
It is indicated by the peel strength when pulled at a speed of 0 mm / min.
Although this peel strength varies depending on the measurement location and the number of measurements, it is important that the minimum value is large, and it is preferable that the peel strength is stable and large. The adhesion described in the present invention is the minimum value of the adhesion of the main part of the mold.

In order to improve the adhesion between the main mold and the heat insulating layer, a general metal / metal such as fine irregularities formed on the surface of the main mold, various kinds of plating, primer treatment, etc.
Methods known in the art of polymer bonding can be used. In general, polyimide has poor adhesion to metals, but polyimides containing a large amount of CO groups and SO ₂ groups, such as polybenzophenone tetracarboxylic acid imide, polyamide imide, and polyimide sulfone, are easy to adhere to metal surfaces. However, although these polyimide resins are excellent in adhesiveness, they are slightly inferior in heat resistance. Therefore, a method in which this thin layer is used as a primer layer and a highly heat resistant polyimide is coated thereon can be particularly preferably used. Also in this case, it is preferable to apply a high heat-resistant polyimide without completing the imidization of the primer layer in order to increase the adhesion.

Injection molding has the greatest merit that a mold having a complicated shape can be formed by one molding, and the mold cavity generally has a complicated shape. It is difficult to cover the surface of the mold cavity having this complicated shape with a heat insulating layer or the like in a mirror surface. Therefore, it is a good method to polish the coated heat-insulating layer later, or to polish the surface with a numerically controlled machine tool such as a numerically controlled milling machine and then to polish the surface to give a mirror-like finish.

The thickness of the heat insulating layer of the heat insulating mold of the present invention is 0.0
It is preferable to select appropriately within a range of 5 to 3 mm, and further within a very narrow range of 0.1 to 0.8 mm. The preferable thickness depends on the molding method, and is preferably 0.1 to 0.5 mm, more preferably 0.12 in injection molding.
~ 0.3 mm. In blow molding, it is preferably 0.3 to 0.8 mm, and more preferably 0.
It is 35 to 0.7 mm. With a thin heat insulating layer of less than 0.05 mm, the effect of improving the mold surface reproducibility of the molded product is small. 3m
If the thickness of the heat insulating layer exceeds m, the cooling time during molding becomes long and the molding efficiency deteriorates.

In the method of manufacturing the heat insulating mold of the present invention, an etching aid is dispersed in at least the upper layer of the heat insulating layer, and the metal layer is formed by etching and plating. The etching aid may be dispersed throughout the heat insulating layer or may be dispersed only in the upper layer of the heat insulating layer. When the etching aid is dispersed only in the upper layer part of the heat insulating layer, the part in which the etching aid is dispersed is called the etching aid containing heat insulating layer, and the part not containing the etching aid is called the base heat insulating layer.

The thickness of the heat insulating layer containing an etching aid is 1 μm.
If it is not more than m, no sufficient effect is exhibited. Preferably 5
It is at least μm, more preferably at least 10 μm. Generally, these etching aids have a higher thermal conductivity than the heat-resistant polymers that make up the etchant-containing layer matrix. The maximum thickness of the etching aid-containing layer may be the entire thickness of the heat insulating layer, but it is preferable to reduce the thickness in order to effectively maintain the heat insulating property. In this case, the preferred maximum thickness is 100μ
m or less, more preferably 50 μm or less. Next, a metal layer is formed on the heat insulation layer by plating after etching. The thickness of the metal layer is preferably 1 to 30.
The thickness is in the range of 0 μm, more preferably 5 to 50 μm, and is preferably 1/3 or less, more preferably 1/5 or less of the thickness of the heat insulating layer. If the metal layer is too thick, the reproducibility of the mold surface of the molded article will decrease, possibly because the heat capacity of the coating layer will increase, and if it is too thin, the coating layer will be easily damaged.

The metal layers are laminated by the following method. If an etching aid is previously dispersed in the upper layer (metal layer side) or the whole of the heat insulating layer, and this is etched, deep etching such as holes, grooves, or cracks caused by etching scratches on the surface of the heat insulating layer will occur. Get hurt. Then, a metal layer firmly bonded to the heat insulating layer can be obtained by subjecting this to chemical plating or the like. Therefore, on the plating interface side of the heat insulating layer of the heat insulating mold of the present invention, the heat-resistant polymer is used as a matrix (continuous phase), and the metal extending from the metal layer is inserted along holes, grooves or cracks. It is a composite structure layer of united metal and metal (hereinafter, abbreviated as composite layer).

The role of this composite layer is to firmly bond the heat insulating layer and the metal layer. Lamination of heat insulation layer and metal layer,
As a bonding method, an ordinary bonding method is naturally conceivable, but it is not possible to sufficiently cover the complicated shape of the heat insulating mold, and a structure having durability against severe shear stress during processing and a heat cycle cannot be obtained. Further, there is a method for producing a heat insulating mold in which the surface of a heat insulating layer which is substantially composed of only a heat resistant polymer containing no etching aid is subjected to chemical modification treatment or simple etching treatment, followed by non-electrolytic plating or / and further electrolytic plating. Already known. However, with such a method, a composite layer is hardly formed, and a structure having sufficient durability against shear stress at the time of molding and a thermal cycle cannot be obtained.

Especially when the heat-resistant polymer is polyimide, USP4775449 and USP484 are limited.
There are known a method of treating the polyimide surface shown in 2946 and the like with alkali and then plating, a method of treating the polyimide surface shown in Japanese Patent Publication No. 6-61897 and the like and then plating. In these conventional metal plating methods of polyimide, the surface is treated with an alkali or the like to make the surface hydrophilic, or after forming fine shallow irregularities on the surface, metal plating is performed. . However, since the metal layer is exposed to severe shear stress and cooling / heating cycles during molding of the synthetic resin, plating with sufficient resistance cannot be achieved only by treating the polyimide surface with alkali or acid.

Further, in these known techniques, there is no idea to improve the plating adhesion strength by using a dispersion as an etching aid during the surface treatment. As a particularly close technique, Japanese Patent Publication No. 6-61897 discloses a heat insulating mold having a heat insulating layer made of halogenated polyimide and a plated metal layer. Moreover, the heat insulating layer has a filler,
Reinforcing agent, as well as pigment, UV absorber, impact resistance agent,
It has been shown that additives such as plasticizers, microwave absorbers, stabilizers, processing aids and antistatic agents can be included.
However, this technique merely discloses that commonly known polymer additives can be added to halogenated polyimides. There is no suggestion or disclosure of the concept and effect of improving the plating peel strength by using the filler as an etching aid as in the present application, not for the purpose of reinforcing the polymer originally.
In addition, as a result of diligent studies, we found that the etching aid cannot achieve a sufficient effect in order to improve the plating adhesion strength unless it is an ultrafine particle filler having an average particle size of 1 to 500 nm. In contrast to the effect of the filler having a particle size of several μm to several tens of μm, which is usually used as a polymer reinforcing agent, the action in plating adhesion is a peculiar effect.

In the method of manufacturing the heat insulating mold of the present invention, all the heat insulating layers or the surface layers of the heat resistant polymer are preliminarily made to have a nonuniform etching-prone structure. That is, the etching aid is dispersed, and the insulating layer and the metal layer are firmly bonded by plating after etching. The particle size of the dispersed etching aid should be in the range of 1 to 500 nm. Preferably 5-100 nm,
More preferably, it is in the range of 10 to 50 nm. The particle size of the etching aid affects the pore size due to etching, and thus the size of the metal insert structure in the composite layer. If the particle size is larger than 500 nm, the plating peeling strength is lowered, which is not preferable.

These ultrafine particle fillers are usually produced by a building-up process (Title: Filler Utilization Dictionary, 17-22,
(1994), Editing: Filler Study Group, Publisher: Inc.
Published by Taiseisha).

The composite layer of the present invention has deep etching flaws such as holes, grooves or cracks formed by etching in the heat resistant polymer matrix, and the metal extending from the metal layer was inserted along the flaws. It is a structure. If the fitting state is a hole, the diameter, if the hole is elliptical, the minor diameter,
Further, in the case of a groove or a crack, the average value of the width is preferably 0.1 to 5 μm, more preferably 0.2 to 2 μm, and particularly preferably 0.3 to 1 μm. An extremely thin metal easily breaks, and if it is too thick, the interfacial area becomes small, so that sufficient resistance to peeling cannot be achieved.

The average thickness of the composite layer is preferably 0.1 to 20 μm, more preferably 0.2 to 5 μm.
Particularly preferably, it is in the range of 0.3 to 2 μm. Insufficient resistance to delamination cannot be achieved without a sufficient composite layer thickness. In addition, even if it is extremely thick, it may not be possible to achieve sufficient resistance to peeling of the metal layer, probably because the resin deteriorates during etching.

Further, it may be preferable in view of peel strength that the structure of the composite layer gradually changes from the metal layer to the polymer layer.

The diameter, the minor axis or the width of the metal inserted in the composite layer is determined by removing the polymer component from the coating layer of the heat insulating mold with a suitable solvent or a decomposing agent, and then the surface of the metal layer is observed with an electron microscope (S
It can be measured by observing with an EM) or observing a cross section of the coating layer with an electron microscope (SEM). The average value can be obtained by dividing the total width by the total number of metal projections in a 10 μm wide cross section of a 5000 × SEM photograph.

Similarly, the thickness of the composite layer can be analyzed by observing the cross section with an electron microscope (SEM). Specifically, the line where the area ratio between the metal and the resin layer in the 10 μm width of the SEM cross-sectional photograph of 5000 times the composite layer thickness is equal is the interface line between the metal and the composite layer, and the tip of the inserted metal root is used. It was obtained by averaging the measured values of 20 randomly selected points, with the width of the composite layer as the thickness of the composite layer.

A particularly preferred embodiment of the method for producing the heat insulating mold of the present invention will be specifically described by taking as an example the case where the heat resistant polymer constituting all heat insulating layers including the composite layer is polyimide.

For example, polyimide is used for the heat insulating layer, and an etching aid such as an inorganic filler is dispersed in the surface layer in advance. The surface of the polyimide layer is etched while decomposing the surface layer with a strong acid, a strong alkali solution, a strong oxidizer solution, a strong reducing agent solution or a combination thereof. At this time, the etching aid dispersed therein is decomposed by the etching aid itself, or the interface between the etching aid and the matrix is decomposed, and the etching aid falls off to form a microscopic deep unevenness. Then, after undergoing neutralization, sensitization treatment, and activation treatment, chemical nickel plating is performed to form a composite layer. The heat treatment is applied and the metal layer is electrolytically plated to firmly bond the heat insulating layer and the metal layer.

As the strong acid used for etching, for example, water of hydrochloric acid, sulfuric acid, nitric acid or a mixed solution of alcohol and the like can be mentioned. As the strong alkali, for example, sodium hydroxide,
A water or alcohol solution such as potassium hydroxide or barium hydroxide may be used. Examples of the strong oxidizer include permanganic acid, dichromic acid and salts thereof,
Examples of the strong reducing agent include hydrazine and the like.
The most preferable etching agent is a system containing permanganic acid or dichromic acid. Further, in the etching reaction, it may be preferable in order to accelerate the etching reaction to swell the surface of the polymer in advance with a solvent having a high affinity with the polymer and an affinity with the etching agent solution.

Next, specific kinds of etching aids and etching methods will be described.

An inorganic filler, an organic filler, an incompatible organic compound or the like is dispersed as an etching aid as uniformly as possible in all or the surface layers of the heat insulating layer made of a heat resistant polymer, and the etching aid is dissolved or decomposed. How to remove. In this method, the etching aid must be dissolved or decomposed in the etching solution.

An inorganic filler, an organic filler, or the like is dispersed as uniformly as possible as an etching aid in all layers or surface layers of the heat insulating layer made of a heat resistant polymer,
A method of infiltrating an etching solution into the interface with an etching aid to partially erode the matrix phase and dropping and removing the filler. In this method, the etching aid does not necessarily need to be dissolved or decomposed in the etching solution.

A method in which a polymer that is easily decomposed or extracted with an etching solution is mixed as an etching aid, or grafted or block copolymerized, and then decomposed or extracted to perform etching.

As described above, the composite layer is a part of the heat insulating layer, and the polymer serving as a matrix is selected from the range of the heat resistant polymer used for the heat insulating layer. Therefore, the description regarding the preferable softening temperature, elongation at break, thermal conductivity, composition and specific examples of the matrix polymer is the same, and the duplication thereof is omitted. When the etching aid is dispersed only in the surface layer of the heat insulating layer and the surface layer portion is a composite layer, the polymer constituting the matrix is the same kind or the same as the polymer constituting the base heat insulating layer. Is preferable in terms of the bondability of the base heat insulating layer. However, different polymers can be selected as long as there is no problem in bonding or bonding with the base heat insulating layer.

When the heat insulating layer containing an etching aid is laminated on the base heat insulating layer, the heat-resistant polymer containing the etching aid dispersed therein is laminated on the base heat insulating layer by the following method. A heat-resistant polymer solution containing dispersed therein, a method of applying and spraying a heat-resistant polymer precursor solution or a liquid precursor, or a method of melting and adhering a mixture of a heat-resistant polymer powder and an etching aid. Available. As a preferred embodiment, a case where the heat-resistant polymer used for the entire heat insulation layer is a polyimide precursor and the etching aid is an inorganic filler will be described in more detail as an example. In this case, for example, a polyimide polymer is selected for the base heat insulating layer, and the precursor applied as the base heat insulating layer is not completely imidized in the cavity of the main mold, and an inorganic filler or the like is dispersed as an etching aid. Particularly preferred is a method in which the same solution of the polyimide precursor contained therein is overlaid and applied, and then heated to complete imidization to form an etching aid dispersion layer.

The inorganic filler is selected from the ultrafine particle type. These are usually made by a forming process. The formation process includes a vapor phase method and a liquid phase method. The vapor phase method as a method for producing fine particles includes an evaporation / condensation method and a vapor phase reaction method. The former method is a method in which a raw material is heated to a high temperature to evaporate, then cooled and condensed into fine particles, and the latter method is a method for synthesizing fine particles by a chemical reaction of a vapor of a metal compound in a gas phase.

The following method can be mentioned as an example of the method for producing ultrafine particles by the gas phase reaction method.

(1) NO ₂ oxidation of chlorides and oxychlorides (2) Oxidation of chlorides and oxychlorides (3) Hydrolysis of volatile metal halides (4) Thermal decomposition of metal alkoxide vapors (5 ) Combustion of metal alkyl (6) Oxidation of metal vapor (7) Hydrogen reduction of chloride in the presence of hydrocarbons (8) Reaction of hydrogen with hydrocarbons (9) Thermal decomposition of silanes (10) With methane Reduction of oxides (11) Reaction of volatile oxides with ammonia (12) Reaction of volatile halides with ammonia

The liquid phase method for synthesizing ultrafine particles includes a chemical method and a physical method. The following chemical methods are available.

(1) Coprecipitation method (2) Uniform precipitation method (3) Compound precipitation method (4) Metal alkoxide method

The following physical methods are available.

(1) Spraying method (2) Solution combustion method (3) Freeze-drying method (4) Emulsion method (5) Nitrate decomposition method

As a detailed explanation of these, there is a description in the aforementioned "filler utilization dictionary". Of these, fillers obtained by the vapor phase method are particularly preferably used.

Examples of the compound species of these fillers are calcium carbonate, silicon oxide, calcium silicate, talc, attapulgite, asbestos, magnesium oxide, magnesium hydroxide, basic magnesium carbonate, hydrotalcite, alumina, aluminum hydroxide. , Aluminum oxide, bentonite, zeolite, kaolin clay, pyrophyllite, sericite, mica, calcium sulfate, calcium sulfite, titanium oxide (rutile,
Anatase), potassium titanate, barium carbonate, barium sulfate, barium titanate, zinc oxide, zirconium oxide, zirconium silicate, iron oxide, molybdenum disulfide, antimony trioxide, silicon nitride, silicon carbide, carbon black, graphite powder, An ultrafine particle powder of an inorganic substance such as carbon fiber can be used. The preferred inorganic filler is calcium carbonate,
Silicon oxide, barium sulfate, zirconium oxide, aluminum oxide and titanium oxide are preferable, and titanium oxide, zirconium oxide and aluminum oxide are particularly preferable.

Examples of organic fillers include ultrafine particles of a polymer having a high softening temperature such as powdery polyimide incompatible with a matrix and powdered polyphenylene ether.

The incompatible organic compound is an organic compound which is incompatible with the heat-resistant polymer serving as a matrix, and is generally a crystalline organic compound. Dispersion of this incompatible organic compound and an etching aid such as a polymer that is easily etched into the heat resistant polymer is usually carried out by applying a uniform solution of the heat resistant polymer to the heat insulating base layer and drying the solvent to remove the etching aid. This can be achieved by insolubilizing and precipitating the agent.

Examples of incompatible organic compounds include various crystalline organic acid compounds and their inorganic salts, amide compounds and ester compounds. Specific examples thereof include polyester compounds such as calcium salts of aliphatic carboxylic acids such as stearic acid and behenic acid and aromatic carboxylic acids, and polyamide compounds.

The polymer which is easily etched also relates to the composition of the etching solution, the heat resistant polymer of the heat insulating layer and the matrix polymer of the composite layer, and is more easily etched than these polymers, that is, more easily eluted or decomposed. It can be widely selected from polymers. For example, when polyimide is used for the heat insulating layer including the composite layer, other polyimide, polyamide, polyester, various conjugated diene polymers and vinyl polymers which are more easily etched are mentioned.

The particle diameters of these etching aids, that is, the particle diameters of the inorganic and organic fillers, and the dispersed particle diameters of the incompatible organic compound and the polymer which is easily etched are as shown above, and the particle diameters are by weight. It is indicated by the average particle size.
If the particles are not spherical, it is difficult to define the particle size,
Here, the spherical equivalent diameter corresponding to either the laser diffraction / scattering method or the sedimentation method, or the spherical equivalent diameter determined by electron microscope analysis is selected.

The amount of the etching aid dispersed in these polymers is in the range of 1 to 50% by volume based on the volume of the etching aid-containing heat insulating layer (when the whole heat insulating layer contains the etching aid). It is preferably 1 to 30% by volume, more preferably 3 to 15% by volume. If the amount of etching aid is too low, or too high, a composite layer with high resistance to metal layer delamination cannot be achieved.

The composite layer and the metal layer constituting the heat insulating mold of the present invention are produced by sequentially plating the heat insulating layer. The plating methods described here are chemical plating (electroless plating) and electrolytic plating. In the actual heat insulation mold manufacturing process, it is not possible to clearly separate both the composite layer and the metal layer in operation. For example, it is continuously obtained by chemical plating and / or electrolytic plating. The metal used is a metal used for general metal plating, and is, for example, one or more of chromium, nickel, copper, and the like.
For example, chemical nickel plating, electrolytic nickel plating, chemical copper plating, electrolytic copper plating, electrolytic chromium plating and the like can be used favorably.

Next, a method of forming a composite layer (composite structure layer of polymer and metal) and a metal layer will be described. The specific method of metal plating after etching described here is merely an example and does not necessarily limit the present invention.

Generally, plating is performed through some of the following steps. For example, when an etching aid-containing heat insulating layer is overlaid on the base heat insulating layer, the etching aid containing heat insulating layer on the base heat insulating layer is first etched. Chemical plating is performed. This chemical plating is, for example, pretreatment → chemical corrosion (chemical etching by acid or alkali) → neutralization → sensitization treatment (metal salt having reducing power is adsorbed and activated on the surface of synthetic resin) → activation treatment (Applying a precious metal such as palladium with a catalytic action to the resin surface) → chemical plating (chemical nickel plating, chemical copper plating, etc.) → heat drying → electrolytic plating (electrolytic nickel plating, electrolytic copper plating, electrolytic chromium plating, etc.) Is generally done in.

The chemical plating is for reducing and depositing metal ions on a metal with a reducing agent. Generally, chemical plating preferably satisfies the following conditions. That is, the reducing agent is stable without self-decomposition in the state where the plating solution is adjusted, the product after the reduction reaction is not precipitated, and the deposition rate can be controlled by pH and solution temperature. It is preferable to satisfy. In chemical nickel plating, sodium hypophosphite, borohydride, or the like is used as a reducing agent, and sodium hypophosphite is particularly preferably used. In order to satisfy the above conditions, auxiliary components (pH adjusting agent, buffer, accelerator, stabilizer, etc.) are added to the chemical plating solution in addition to the main components (metal salt, reducing agent).

Various plating layers can be further formed on the chemical plating (for example, chemical nickel plating) which is firmly adhered to the heat insulating layer while forming the composite layer on the heat insulating layer. Preferred examples thereof are shown below. Preferably, at least one layer selected from these platings is coated.

Chemical Nickel Plating Electrolytic Nickel Plating Chemical Copper Plating Electrolytic Copper Plating Electrolytic Chromium Plating

The most preferable embodiment of the plated metal layer structure is as follows.
It is obtained by sequentially performing chemical nickel plating, displacement copper plating, strike copper plating, electrolytic copper plating, electrolytic nickel plating, and electrolytic chromium plating. In addition, putting a heat-drying step after the chemical nickel plating may show a preferable effect in improving the plating peel strength.

The surface of the metal layer formed by plating can be processed into a grain shape if necessary. The grain processing can be performed by various methods. The etching method can be used favorably, and the etching method using an acid can be best used. If the outermost surface layer of the heat-insulating mold is a metal that can be etched with an acid solution such as electrolytic nickel plating, electrolytic copper plating, or chemical nickel plating with low phosphorus content, the etching method used for general metal mold graining is used. Graining can be performed in the same manner as described above. That is, a method in which the surface of the metal layer is masked with an ultraviolet curable resin in a grain shape and then grained by acid etching can be favorably used.

By laminating a metal layer on the surface of the heat insulating mold, scratches and releasability of the mold surface are improved. In a heat insulating mold coated only with a heat insulating layer made of only a heat resistant polymer without a metal layer, if a synthetic resin containing 15 to 60% by weight of glass fiber is injection-molded, the heat insulating layer on the surface of the mold is easily made of glass fiber. Is scratched. Scratching can be prevented by laminating a metal layer on the surface. Further, polyamide resins, resins having a high acrylonitrile content, etc. generally have poor releasability with the heat insulating layer, but by laminating a metal on the surface of the heat insulating layer, it is possible to improve the releasability during molding. can get.

The surface of the metal layer may be mirror-like, matte or grain-like, and is selected according to the purpose. When the surface of the metal layer is matte, the average thickness is taken as the thickness of the metal layer. That is, the thickness from the average line measured by JIS B0601 to the interface with the composite layer is defined as the average thickness. Further, when the surface of the metal layer has a grain-like unevenness, the thickness from the metal layer convex portion forming the grain shape to the interface with the composite layer is defined as the metal layer thickness of the heat insulating mold of the present invention. The grain shape that can be favorably used in the present invention is a grain pattern such as a leather grain pattern, a grain pattern and a hairline pattern.

Generally, the thickness of the heat insulating layer and the thickness of the metal layer are preferably 0.05 to 3 mm and 1 to 300 μm, respectively, and 1/3 or less of the thickness of the heat insulating layer. The surface differs depending on whether it is mirror-like, matte, or grain-like. Further, the molding method used also differs depending on whether injection molding, blow molding, or the like. The more preferable thickness of the heat insulating layer and the more preferable thickness of the metal layer in a typical molding method are shown below.

When molding a mirror-like or matte-like molded product by the injection molding method, it is particularly preferable that the heat insulating layer has a thickness of 0.1 to 0.5 mm and the metal layer has a thickness of 1 of the heat insulating layer thickness.
/ 7 or less and 2 to 40 μm. Most preferably, the thickness of the heat insulating layer is 0.12 or more and less than 0.3 mm, the thickness of the metal layer is 1/10 or less, 1/100 or more of the thickness of the heat insulating layer, and 2 to 25 μm.

When molding a grain-shaped molded article by an injection molding method, it is particularly preferable that the heat insulating layer has a thickness of 0.1 to 0.5.
In mm, the thickness of the convex portion of the metal layer is 1/7 or less of the thickness of the heat insulating layer and 10 to 40 μm, and the depth of the grain-shaped concave portion is 5 to 35 μm. Most preferably, the thickness of the heat insulating layer is 0.12 or more and less than 0.3 mm, the thickness of the convex portion of the metal layer is 1/7 or less of the thickness of the heat insulating layer, and 10 to 35 μm.
And the depth of the grain-shaped concave portion is 5 to 30 μm. If the depth of the concave portion is too large, a large difference is likely to occur in the mold surface reproducibility between the concave portion and the convex portion. On the other hand, if the depth of the concave portion is too small, the effect of forming the grain shape is reduced.

When a mirror-like or matte shaped article is formed by blow molding, it is particularly preferable that the thickness of the heat insulating layer is 0.3 to 0.8 mm and the thickness of the metal layer is 1 of the thickness of the heat insulating layer.
/ 7 or less, and 2 to 40 μm, most preferably the thickness of the heat insulating layer is 0.35 to 0.7 mm, the thickness of the metal layer is 1/10 or less, 1/100 or more of the thickness of the heat insulating layer, And 2 to 30 μm.

When a grain-shaped molded article is formed by blow molding, it is particularly preferable that the thickness of the heat insulating layer is 0.3 to 0.8 m.
m, the thickness of the convex portion of the metal layer is 1/7 or less of the thickness of the heat insulating layer and 10 to 40 μm, and the depth of the grain-shaped concave portion is 5 to 35 μm. Most preferably, the thickness of the heat insulating layer is 0.3 to 0.7 mm, the thickness of the convex portion of the metal layer is 1/7 or less of the thickness of the heat insulating layer and 10 to 35 μm, and the depth of the grain-shaped concave portion is It is 5 to 30 μm.

In the heat-insulating mold of the present invention, when the metal layer surface has irregularities on the surface of the metal layer, the metal layer thickness is defined as the thickness of the convex portion of the metal layer forming the grain shape. This is to improve the condition and reduce the conspicuousness such as weld lines in the entire molded product. The appearance of the grain is preferably such that one of the convex and concave portions is a mirror surface, and the other is a matte surface.

The thickness of the metal layer is preferably uniform, and the variation in thickness is preferably ± 10% or less, more preferably ± 5% or less. In the case where the metal layer surface has grain-like irregularities, the thickness of the metal layer of the convex portion or the thickness of the metal layer of the concave portion is preferably uniform, and the variation in each thickness is preferably ± 10% or less, More preferably, it is ± 5% or less. If the variation in the metal layer thickness is large, the mold surface reproducibility of the thick portion of the metal layer deteriorates, and a portion having good mold surface reproducibility and a portion having poor mold surface reproducibility appear on the same molded product surface, and unevenness is likely to occur.

The synthetic resin molded by the molding method using the heat insulating mold of the present invention is a thermoplastic resin that can be used in general injection molding and blow molding, and examples thereof include polyolefin such as polyethylene and polypropylene, polystyrene, and styrene-acrylonitrile. Examples thereof include copolymers, rubber-reinforced polystyrene, styrene resins such as ABS resin, polyamide, polyester, polycarbonate, methacrylic resin, vinyl chloride resin, and polyphenylene ether.

The synthetic resin preferably contains 1 to 60% by weight of a resin reinforcement. The resin-reinforced material includes various fibers such as various rubbers, glass fibers, and carbon fibers, and inorganic powders such as talc, calcium carbonate, and kaolin.
The heat-insulating mold obtained in the present invention can be used particularly effectively when the content of rubber-reinforced polystyrene resin and glass fiber is 15
-60% by weight of various synthetic resins, polyamide resins such as nylon 66 and nylon 6, acrylonitrile-styrene copolymers having a high acrylonitrile content, and ABS resins having the copolymer as a matrix.

In molding a synthetic resin by using the heat insulating mold of the present invention, the mold temperature is preferably set to (softening temperature of synthetic resin −20 ° C.) to (room temperature), more preferably (synthetic resin). (Softening temperature of −30 ° C.) to (room temperature + 5 ° C.) for molding. By setting such a mold temperature, it is possible to obtain a molded product that is excellent in mold reproducibility and appearance in imparting the shape state of the mold surface of the molded product.

Further, by using the heat insulating mold of the present invention, the conspicuousness of the weld line of the synthetic resin molded product can be reduced, the reproducibility of the mold surface can be improved, and the post processing after molding can be omitted. It is possible to reduce scratches on the surface of the mold during molding, as compared with the case of using a mold in which the outermost surface of the mold is composed of a heat insulating layer containing only a heat resistant resin. Further, the mold releasability can be improved, and the durability of the mold at the time of molding for a long period of time, especially the durability of a portion having a small draft can be improved.

The mold temperature described here is the temperature at the time of molding of the main mold in the portion in contact with the heat insulating layer. If the mold temperature is higher than this, the molding cycle time becomes longer and the molding efficiency is lowered. Further, if the mold temperature is below room temperature, problems such as dew condensation easily occur on the mold surface.

The heat insulation mold of the present invention is, for example, a light electric machine,
Housing for electronic equipment, office equipment, various automotive parts,
Used for molding general synthetic resin injection molded products such as various daily necessities and various industrial parts. Particularly preferably, it is used for housings of electronic equipment, electric equipment, office equipment, etc. where weld lines are easy to appear, and because of its extremely excellent mold reproducibility and appearance, effects such as omitting post-processes such as painting and lowering manufacturing costs can be achieved. Can be achieved. Molding using the heat insulating mold is generally performed by an injection molding method, but the pressure of the synthetic resin pressing the mold wall surface at the time of molding such as gas-assisted injection molding and injection compression molding is low, and / or the mold of the synthetic resin is used. The improvement effect is particularly great when used in combination with low-pressure injection molding, which has a low internal flow rate. Also, in various blow molding methods,
The improvement effect is particularly great when used in blow molding in which it takes a long time for the parison to contact the mold wall surface and for the blow pressure to be sufficiently applied to the inner surface of the molded product.

Next, examples of the structure of the heat insulating mold of the present invention will be described with reference to the drawings, but these do not limit the present invention. 1 to 3 are sectional views showing the vicinity of the mold surface of the heat insulating mold of the present invention.

In FIG. 1, a base heat insulating layer 2 made of a heat-resistant polymer is present on the mold wall surface of a mold cavity of a main mold 1 made of metal, and an etching aid-containing layer and a composite structure are formed thereon. There is a layer 3 consisting of layers (composite layers), the first
There is a metal layer B composed of the metal layer 4 and the second metal layer 5. The heat insulation layer B is a combination of the layers 2 and 3.

The metal layer B is required to be firmly bonded to the heat insulating base layer 2 with the layer 3 interposed therebetween. To achieve this,
It is preferable that the metal layer B and the metal portion fitted in the layer 3 are composed of two or more layers. A preferred layer configuration is
The metal composition constituting the composite layer and the first metal layer 4 is a layer composed of a low phosphorus chemical nickel plating layer having a relatively low phosphorus content, on which electrolytic copper plating having a relatively high phosphorus content and a high phosphorus chemical nickel plating layer are formed. It is preferable to provide one or more layers selected from a plating layer, an electrolytic nickel plating layer, and an electrolytic hard chrome plating layer.

FIG. 2 shows a case where the metal layer B is three layers. The metal portion of the layer 3 and the first metal layer 4 in contact therewith are a low phosphorus chemical nickel plating layer having a relatively low phosphorus content, and a second metal comprising a high phosphorus chemical nickel plating layer having a relatively high phosphorus content thereon. The layer 5 has a three-layer structure including the layer 5 and the third metal layer 6 formed of the electrolytic hard chromium plating layer on the layer 5. Main mold 1, base heat insulation layer 2 and layer 3
The heat-insulating layer B consisting of is the same as that in FIG.

FIG. 3 shows an example of the structure of a heat insulating mold having a grain surface. The metal portion of the layer 3 and the first metal layer 4 in contact therewith are a low phosphorus chemical nickel plating layer, and an electrolytic nickel plating layer or an electrolytic copper plating layer having a high sulfur content and generally called bright nickel. There is a second metal layer 5 consisting of The second metal layer 5 is formed into a grain shape by acid etching or the like, and a metal layer having excellent corrosion resistance is formed on the second metal layer 5, for example, a chemical nickel plating layer having a high phosphorus content or an electrolytic hard chromium plating layer. It is a metal layer B with 6. Between the first metal layer 4 and the second metal layer 5, an electrolytic nickel plating layer called semi-bright nickel having a low sulfur content may be further present. The heat insulating layer a including the main mold 1 and the base heat insulating layer 2 and the layer 3 is the same as that shown in FIG.

The operation and effect of using the heat insulating mold of the present invention for molding will be shown by the simulation calculation result.

4, 5, 6, 7, 8, and 9, a mold having a surface of a main mold made of steel and a polyimide layer on the surface of the main mold, and a nickel layer on the surface of the main mold are compared with polyimide. The calculation results using a mold in which only layers are coated are shown. When the temperature of the main mold is set to 50 ° C. and the rubber-reinforced polystyrene resin is injection molded at the temperature of 240 ° C. in the mold,
The change over time in the temperature of the resin surface after the resin contacts the outermost surface of the mold is shown.

FIG. 4 shows the resin surface temperature when the thickness of the polyimide (hereinafter indicated by PI in the figure) layer is 0.30 mm and the thickness of the nickel (hereinafter indicated by Ni in the figure) layer is 0.02 mm. The change over time is shown. In this calculation, the thickness of the composite layer was set to 0.

In the figure, the solid line shows the case where the polyimide layer and the nickel layer are coated, and the broken line shows the case where only the polyimide layer is coated. When only polyimide is coated, the resin surface temperature gradually decreases with time, whereas when the polyimide layer and nickel layer are coated, the temperature drops once and then rises again and then gradually decreases. To do. This is because the heat of the resin is absorbed by the nickel layer because the heat capacity of nickel in the surface layer is large, and the heat is once reduced. Therefore, as the thickness of the nickel layer increases,
The temperature range in which the temperature once drops increases, and the temperature in which the temperature rises again decreases.

Although not shown in the figure, in the case of a conventional mold having no coating layer, the resin surface temperature is the mold temperature 50.
It is instantly cooled to ℃ and does not change over time.

FIG. 5 shows the case where the thickness of the nickel layer is as thick as 0.1 mm. When the thickness of the nickel layer is thick, the temperature range that once drops is large and the temperature that rises again is low.

FIGS. 6 and 7 show the case where the thickness of the polyimide layer is 0.15 mm with the same layer structure as in FIGS. 4 and 5. Even when the thickness of the polyimide layer is 0.15 mm, the same tendency as in FIGS. 4 and 5 is observed.

FIGS. 8 and 9 collectively show the results of FIGS. 4 to 7. In the case of a mold coated with a nickel layer, when the thickness of the nickel layer becomes 0.1 mm, the temperature of the surface that has once dropped will rise again, and the temperature will decrease again, and the reproducibility of the mold surface during injection molding will decline. Can be estimated. When the thickness of the nickel layer is 0.02 mm, the resin surface temperature recovers rapidly even if it once drops, and the temperature is high. Changes in the mold surface temperature during injection molding shown in these figures are as follows: synthetic resin, main mold, temperature of heat insulating layer, specific heat, thermal conductivity, density,
It can be calculated from latent heat of crystallization. For example, ABAQUS
(Software of HKS, USA) and ADINA and A
It can be calculated by unsteady heat conduction analysis by the nonlinear finite element method using DINAT (software developed at Massachusetts Institute of Technology). The temperature shown is ABAQU
It is calculated using S.

The meaning of this calculation result is to predict the improvement in moldability by statically maintaining the shape of the resin in the mold after injection in a high temperature plasticized state for a certain period of time. . This calculation result is in good agreement with the mold surface reproducibility during injection molding in the actual test.

From the above, in order to improve the mold surface reproducibility, it is preferable to appropriately select the thickness of the heat insulating layer and the thickness of the metal layer covering the surface of the heat insulating layer. That is, it is possible to provide a heat insulating mold capable of efficiently forming a molded product having a good appearance by coating a heat insulating layer having an appropriate thickness with a metal layer having an appropriate thickness.

[0117]

EXAMPLES The present invention will be described below with reference to examples. The manufacturing method of the metal layer and the type of characteristics in this embodiment will be summarized first.

Metal layer A: Sodium hypophosphite as a reducing agent,
Low phosphorus chemical nickel plating with low phosphorus content formed by chemical nickel plating at low temperature, weak alkaline condition and low speed.

Metal layer B: Sodium hypophosphite as a reducing agent,
Medium-phosphorus chemical nickel plating with relatively high phosphorus content formed by chemical nickel plating at high temperature, acidic condition and high speed.

Metal layer C: Bright electrolytic nickel plating with high sulfur content.

Metal layer D: sodium hypophosphite as a reducing agent,
High phosphorus chemical nickel plating with high phosphorus content, which is formed by chemical nickel plating at high temperature, acidic condition and high speed.

Metal layer E: Semi-bright electrolytic nickel plating with low sulfur content.

Metal layer F: Copper strike plating using copper sulfate Metal layer G: Electrolytic copper plating using copper sulfate plating bath

Example 1 1. Method for manufacturing heat insulating mold (1) Main mold This is a mold made of steel (S55C) for injection molding. The coefficient of thermal expansion of the mold is 1.1 × 10 ^-5 / ° C. It has a mold cavity for the molded article 8 shown in FIG. Molded product size is 1
00mm × 100mm, thickness is 2mm, 3 in the center
There is a hole 9 of 0 mm × 30 mm. The gate 10 is a side gate as shown in FIG. 10, and a weld line 11 is generated in the molded product 8. The mold surface is mirror-like. An insert forming the mold cavity of this main mold was prepared, and the surface of each insert was plated with hard chrome. (2) Thermal insulation layer Primer layer: A 10 wt% solvent solution of a linear polyimide precursor having a large amount of CO groups is sprayed onto the nested surface of the main mold as a primer and applied to a thickness of about 1 μm.
It was dried at 60 ° C. for 20 minutes and partially imidized.

Base heat insulating layer: A mixed solution containing "Trenis # 3000" (manufactured by Toray Industries, Inc.) as a base heat insulating layer was repeatedly spray-coated on the primer. After each spray coating, heating was performed at 160 ° C. for 20 minutes. This coating and heating were repeated to obtain a thickness of 200 μm. The composition of the coating liquid is as follows. These liquids were mixed with a paint shaker.

Polypyromellitic imide-based polyimide precursor 15.9% by weight (weight as nonvolatile content after curing) Thixotropic agent 0.3% by weight Solvent (mixture of dimethylacetamide, N-methylpyrrolidone and aromatic hydrocarbon) 83.8% by weight of etching aid-containing layer: Finally, titanium oxide (average particle size 20 nm) produced by a gas phase reaction method was dispersed or dissolved as an etching aid in order to form a composite layer. A mixed solution containing "Trenis # 3000" (manufactured by Toray Industries, Inc.) was spray-coated to cover the outermost surface with a heat insulating layer containing an etching aid having a thickness of 10 μm, and then heated to 290 ° C. to form a polyimide layer. The composition of the mixed solution was 10% non-volatile after curing of "Treney # 3000" (manufactured by Toray).
It is the same as the liquid composition in the base heat insulating layer except that 0 part by weight is mixed with 11.0 parts by weight of the etching aid. These liquids were mixed with a paint shaker.

Incidentally, the spray coating of the heat insulating layer, the heat drying and the imidization reaction were all carried out under a nitrogen atmosphere. The thermal expansion coefficient of the polyimide of the base heat insulation layer is 3.3 × 10 ^-5 / ° C.
It is. The specific gravity of the cured product of Treney's # 3000 is 1.4.
The true specific gravity of the acid value titanium was 2 g / ml and 3.7 g / ml, and the content value of the acid value titanium in the etching aid-containing heat insulating layer was 4.1% by volume. (3) Plating method Etching method: The mold coated with the obtained heat insulating layer was etched at 60 ° C. for 20 minutes while stirring using a mixed solution of potassium dichromate and sulfuric acid. After the etching, the surface of the heat insulating layer was sufficiently neutralized and washed with water.

Plating method: The heat-insulating layer surface of the obtained mold is subjected to a sensitizing treatment and an activating treatment in this order, and then chemical nickel plating is performed to form a metal layer A having a thickness of 0.5 μm.
Was coated on its surface with a metal layer B of 5 μm, and further on its surface with a metal layer D.

[0129] 2. Performance Evaluation of Insulating Mold Using this insulating mold, rubber-reinforced polystyrene resin "Asahi Kasei Polystyrene 492" (manufactured by Asahi Kasei Kogyo Co., Ltd.) as a thermoplastic resin was injection-molded. The metal layer of the heat insulating mold and the heat insulating layer were firmly adhered to each other, and peeling did not occur even after 10,000 injection moldings. The molded product had no visible weld lines and was excellent in appearance. In addition, when the heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure, and the peeling strength of the plated surface was 1.6 kg / 10 mm width. The peel strengths in Examples and Comparative Examples were measured after copper plating, when the plated layer was easily broken.

The thickness of the heat insulating layer (the sum of the base heat insulating layer and the composite layer) is 200 μm, the thickness of the composite layer (composite structure layer of polymer and metal) is 1.2 μm, and the thickness of all metal layers is 10.5 μm. there were.

Example 2 The same procedure as in Example 1 was carried out except that the etching aid was aluminum oxide (average particle size: 15 nm, specific gravity: 3.2 g / ml) produced by the gas phase reaction method.

Using this heat insulation mold, the above-mentioned "Asahi Kasei Polystyrene 492" (manufactured by Asahi Kasei Kogyo Co., Ltd.) as a thermoplastic resin was injection-molded. The metal layer of the heat insulating mold and the heat insulating layer were firmly adhered to each other. The molded product had no visible weld lines and was excellent in appearance. Further, when the heat insulating mold manufactured in the same manner was analyzed and evaluated, the following laminated structure was obtained, and the peel strength of the plated surface was 1.7 Kg / 10 mm width.

The heat insulating layer had a thickness of 200 μm, the composite layer had a thickness of 1.8 μm, and the total metal layers had a thickness of 10.1 μm.

Example 3 The same procedure as in Example 1 was carried out except that the etching aid was calcium carbonate (average particle size 80 nm, specific gravity 2.5 g / ml) produced by the liquid phase precipitation method.

Using this heat insulating mold, the above-mentioned "Asahi Kasei Polystyrene 492" (manufactured by Asahi Kasei Corporation) was injection-molded as a thermoplastic resin. The metal layer of the heat insulating mold and the heat insulating layer were firmly adhered to each other. The molded product had no visible weld lines and was excellent in appearance. In addition, when the heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure, and the peel strength of the plated surface was 0.95 Kg / 10 mm.
It was wide.

The thickness of the heat insulating layer (the sum of the base heat insulating layer and the composite layer) was 200 μm, the thickness of the composite layer was 2.2 μm, and the thickness of all the metal layers was 9.8 μm.

Example 4 As Example 1 except that the etching aid was zirconium oxide produced by a gas phase reaction method (average particle size 30 nm, specific gravity 5.4 g / ml), and all the operations were performed in air. It carried out similarly.

Using this heat insulating mold, the above-mentioned "Asahi Kasei Polystyrene 492" (manufactured by Asahi Kasei Kogyo Co., Ltd.) as a thermoplastic resin is injection-molded. The metal layer of the heat insulating mold and the heat insulating layer were firmly adhered to each other. The molded product had no visible weld lines and was excellent in appearance. In addition, when the heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure, and the peeling strength of the plated surface was 1.6 kg / 10 mm width.

The heat insulating layer had a thickness of 200 μm, the composite layer had a thickness of 1.1 μm, and the total metal layers had a thickness of 10.8 μm.

Example 5 The coating of the primer layer was omitted, and the polyimide of the heat insulation layer was replaced with "U".
PILEX-S "(manufactured by Ube Industries, Ltd.), that is, a precursor of a polybiphenyltetracarboxylic acid imide-based polyimide, was performed in the same manner as in Example 1.

The above-mentioned "Asahi Kasei Polystyrene 492" (manufactured by Asahi Kasei Kogyo Co., Ltd.) was injection-molded as a thermoplastic resin using this heat insulating mold. The metal layer of the heat insulating mold and the heat insulating layer were firmly adhered. The molded product had no visible weld lines and was excellent in appearance. Further, when the heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure, and the peel strength of the plated surface was 1.5 kg / 10 mm width.

The heat insulating layer had a thickness of 200 μm, the composite layer had a thickness of 1.0 μm, and the total metal layers had a thickness of 11.0 μm.

Example 6 A primer layer, a base heat insulating layer and an etching aid containing layer were formed in the same manner as in Example 1, and after further etching, the metal layer A was used.
Of 0.5 μm thick first metal layer on the surface of
m of the metal layer B, and the surface thereof was further coated with the metal layer C having a thickness of 15 μm. Then, the metal layer C was etched to a depth of 10 μm to form a grain surface. Further, the grainy surface was coated with a metal layer D having a thickness of 2 μm. The average thickness of the entire metal layer was 15 μm.

Injection molding of a thermoplastic resin was performed using this heat insulating mold. The metal layer and the heat insulating layer are firmly adhered,
No peeling occurred even after 10,000 injection moldings. The molded product had no conspicuous weld line and was an excellent molded surface. Also, analyze the heat insulation mold manufactured in the same way,
When evaluated, the following laminated structure was obtained, and the peel strength of the plated surface was 1.7 kg / 10 mm width.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was 1.0 μm, the average thickness of all metal layers was 15 μm, and the metal layer thickness of the convex portions was 22.5 μm.

Example 7 The procedure of Example 6 was repeated, except that the metal layer E was used instead of the metal layer B. The metal layer and the heat insulating layer were firmly attached. The molded product had no conspicuous weld line and was an excellent molded surface. Analyze the same heat insulation mold,
When evaluated, the following laminated structure was obtained, and the peel strength of the plated surface was 1.7 kg / 10 mm width.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was 1.3 μm, the average thickness of all metal layers was 15 μm, and the metal layer thickness of the convex portions was 22.2 μm.

Example 8 The coating of the primer layer was omitted, the polyimide of the entire heat insulating layer was "Treney # 3000" (manufactured by Toray Industries, Inc.), and the thickness of the heat insulating layer was 1 mm. Other than that, the etching process was performed in the same manner as in Example 1. The surface of the heat insulating layer of the mold is coated with a first metal layer having a thickness of 0.5 μm of the metal layer A, the surface thereof is coated with a metal layer B having a thickness of 5 μm, and the surface thereof is further coated with 5 μm.
A thick metal layer D was coated.

Injection molding of a thermoplastic resin was performed using this mold. The molded product had no noticeable weld line and good gloss, but the resin cooling time was slightly long, the molding time cycle was long, and the molding efficiency was slightly inferior. The heat insulation mold manufactured in the same manner was analyzed and evaluated, and it was the following laminated structure, and the peeling strength of the plated surface was 1.6 kg / 10 mm.
It was wide.

The heat insulating layer had a thickness of 1 mm, the composite layer had a thickness of 1.6 μm, and the total metal layers had a thickness of 10.4 μm.

Example 9 The same process as in Example 8 was carried out up to the etching step except that the thickness of the heat insulating layer was 200 μm. On the surface of the heat insulating layer of the mold,
The metal layer A is coated with a first metal layer having a thickness of 0.5 μm, the surface thereof is coated with a metal layer B having a thickness of 5 μm, and the surface thereof is further coated with 50 μm.
A μm thick metal layer C was coated. Next, the metal layer C is
Etching was performed to a depth of m to form a grain surface. Further, this surface was coated with a metal layer D having a thickness of 2 μm.

Injection molding of a thermoplastic resin was performed using this heat insulating mold. The molded product has a slightly noticeable weld line. When a heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure and had a peeling strength of the plated surface of 1.5 kg / 10 mm width.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was 1.4 μm, the thickness of all the convex metal layers was 56.8 μm, and the thickness of all the concave metal layers was 27.1 μm.

Example 10 The same processes as in Example 1 were carried out up to the etching step. The surface of the heat insulating layer of the mold is coated with a thickness of 0.5 μm of the metal layer A, and a thin layer of substitution copper is applied to the surface thereof, and then the metal layer F of 1 μm,
m of the metal layer G and 5 μm of the metal layer E were coated, and the surface thereof was further coated with the metal layer C of 35 μm in thickness. Next, the metal layer C was etched to a depth of 25 μm to form a grain surface.

A thermoplastic resin was injection-molded using this heat insulating mold. The molded product has a slightly noticeable weld line. When a heat insulating mold manufactured in the same manner was analyzed and evaluated, it had the following laminated structure and had a peeling strength of the plated surface of 1.5 kg / 10 mm width.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was 1.1 μm, the thickness of all the convex metal layers was 45.5 μm, and the thickness of all the concave metal layers was 20.4 μm.

Comparative Example 1 In the final step of forming the heat insulating layer, a thin layer containing an etching aid was not formed, and only the polyimide single layer was used as the heat insulating layer. The coating conditions, heating conditions, etching, etc. were the same as in Example 1. Although the metal layer of the obtained mold was in close contact with each other for some time, partial peeling of the surface metal layer was already observed after 10 injection moldings. When a heat insulating mold produced in the same manner was analyzed and evaluated, it had the following laminated structure and had a peel strength of 0.4 Kg / 10 mm width on the plated surface.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was less than 0.1 μm, and the thickness of all mold layers was 10.5 μm.

Comparative Example 2 The procedure of Example 1 was repeated, except that the etching aid was calcium carbonate (average particle size: 3 μm, specific gravity: 2.5 g / ml) produced by a crushing method. When injection molding was carried out using this, partial peeling of the surface metal layer was observed after 70 injection moldings. When a heat insulating mold produced in the same manner was analyzed and evaluated, it had the following laminated structure and had a peel strength of 0.6 kg / 10 mm width on the plated surface.

The thickness of the heat insulating layer was 200 μm, the thickness of the composite layer was less than 0.1 μm, and the thickness of all mold layers was 11.0 μm.

[0161]

The heat-insulating mold of the present invention has the metal layer firmly adhered to the surface of the heat-insulating layer, and achieves extremely excellent resistance to the cold heat cycle and shear stress during molding.
Further, by optimizing the layer structure of the heat insulating layer and the metal layer, a molded product having a good appearance can be efficiently obtained in injection molding or blow molding of synthetic resin. further,
In the injection molding of the housing of light electric equipment or office equipment, which has conventionally required a lot of weld lines and requires post-processing such as painting, the weld lines are less noticeable and painting can be omitted.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a heat insulating mold obtained by the present invention.

FIG. 2 is a cross-sectional view showing another example of the heat insulation mold obtained by the present invention.

FIG. 3 is a cross-sectional view showing another example of the heat insulation mold obtained by the present invention.

[Fig. 4] Synthesis when heated synthetic resin comes into contact with a mold in which the surface of the main mold made of steel is coated with 0.3 mm of polyimide and 0.02 mm of nickel is further coated on the surface of the mold. It is a graph which shows the temperature change (calculation value) of the resin surface (interface between resin surface and mold surface).

FIG. 5: Synthesis when heated synthetic resin comes into contact with a mold in which the surface of a steel main mold is coated with 0.3 mm of polyimide, and the surface of which is further coated with 0.1 mm of nickel It is a graph which shows the temperature change (calculation value) of the resin surface (interface between resin surface and mold surface).

[FIG. 6] Synthesis when heated synthetic resin comes into contact with a mold in which the mold surface of the main mold made of steel is coated with 0.15 mm of polyimide, and the surface of which is further coated with nickel of 0.02 mm It is a graph which shows the temperature change (calculation value) of the resin surface (interface between resin surface and mold surface).

FIG. 7: Synthesis when heated synthetic resin comes into contact with a mold in which the surface of a steel main mold is coated with 0.15 mm of polyimide, and the surface of which is further coated with nickel of 0.1 mm It is a graph which shows the temperature change (calculation value) of the resin surface (interface between resin surface and mold surface).

FIG. 8: The surface of the main mold made of steel is coated with 0.3 mm of polyimide, and the surface is further covered with 0.0005 mm,
The temperature change (calculated value) of the synthetic resin surface (the interface between the resin surface and the mold surface) when the heated synthetic resin comes into contact with the mold coated with nickel of 0.02 mm and 0.1 mm in thickness It is a graph shown.

FIG. 9: The surface of the main mold made of steel is coated with 0.15 mm of polyimide, and the surface thereof is further covered with 0.0005 mm,
The temperature change (calculated value) of the synthetic resin surface (the interface between the resin surface and the mold surface) when the heated synthetic resin comes into contact with the mold coated with nickel of 0.02 mm and 0.1 mm in thickness It is a graph shown.

FIG. 10 is a perspective view of injection-molded products used in Examples and Comparative Examples.

[Explanation of symbols]

 A heat insulating layer b metal layer 1 main mold 2 base heat insulating layer 3 etching aid containing layer and composite layer 4 first metal layer 5 second metal layer 6 third metal layer 7 grainy metal layer surface 8 molded product 9 holes 10 gate 11 weld line

Claims (10)

[Claims] 1. A heat-resistant heavy material containing, on the mold cavity wall surface of a main mold made of metal, an etching aid having an average particle size of 1 to 500 nm dispersed in at least an upper layer in a range of 1 to 50% by volume. A method for producing a heat-insulating mold comprising a main mold, a heat-insulating layer, and a metal layer, which is obtained by forming a metal layer by etching and plating after providing a heat-insulating layer made of a united body. 2. The method for producing a heat insulating mold according to claim 1, wherein the etching aid is an inorganic filler. 3. The method for producing a heat insulating mold according to claim 1, wherein the etching aid is a metal oxide obtained by a gas phase reaction method. 4. The etching aid is aluminum oxide, titanium oxide, zirconium oxide, antimony oxide, chromium oxide,
The method for producing an adiabatic mold according to claim 1 or 3, which is selected from ferric oxide, germanium oxide, vanadium oxide and tungsten oxide. 5. The method for producing a heat insulating mold according to claim 4, wherein the etching aid is titanium oxide. 6. The method for producing a heat insulating mold according to claim 4, wherein the etching aid is aluminum oxide. 7. The method for producing an adiabatic mold according to claim 1, wherein the heat-resistant polymer is polyimide. 8. The metal layer comprises a chemical and / or electro-nickel plating layer.
Manufacturing method of heat insulation mold. 9. An adiabatic mold obtained by the manufacturing method according to claim 1. 10. The thickness of the heat insulating layer is in the range of 0.05 to 3 mm, the thickness of the metal layer is in the range of 1 to 300 μm, and is 1/3 or less of the thickness of the heat insulating layer.
Heat insulation mold.