JPWO2020137351A1 - Injection molding mold, injection molding mold manufacturing method and resin molded product manufacturing method - Google Patents

Abstract

The subject of the present invention is an injection molding die made of an aluminum alloy, having an excellent strength against impact and sliding during molding, and having a coating film having excellent durability against a molding resin, a manufacturing method thereof, and an injection molding die. It is to provide the manufacturing method of the resin molded article using a mold. The injection molding mold of the present invention is a mold for injecting a molten resin into a cavity of a mold and transferring the shape of the cavity to the resin to form a resin molded product, and the cavity is fixed. It is formed between the mold member and the movable mold member, or between the fixed mold member and the movable mold member and the slide core constituting the sliding portion, and is at least one of the fixed mold member, the movable mold member and the slide core, which is an aluminum alloy. It is characterized in that at least one of the surfaces of the aluminum alloy has a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum.

Description

The present invention relates to an injection molding die, a method for manufacturing an injection molding die, and a method for manufacturing a resin molded product. More specifically, the present invention relates to an injection molding die made of an aluminum alloy and having excellent durability, a method for manufacturing the same, and a method for manufacturing a resin molded product using the injection molding die.

In the injection molding method, a molten resin is injected into a cavity (resin molding part) of an injection molding mold composed of a fixed mold member and a movable mold member, and after the resin is solidified, the fixed mold member and the movable mold member are movable. This is a method of taking out a resin molded product by separating the mold members.

Conventionally, the resin applied to molding is high temperature and high pressure, and the size and shape of the molded product to be manufactured change depending on the mold temperature at the time of molding, so high precision is particularly required, and it is applied to such fields. As a constituent material of a mold for injection molding, a steel mold having high strength and hardness has been widely used.

However, due to the high hardness of the steel mold, the processing time becomes long at the time of mold production, and it is difficult to manufacture the mold having a fine structure, which is caused by them. The manufacturing cost of the mold is high, and there are problems such as thermal conductivity and heavy mold.

In recent years, in order to solve various problems of the above-mentioned steel molds, molds using various materials other than steel have been studied.

Among them, the aluminum mold, which has a lower hardness than the steel material, has good workability, and not only the mold manufacturing time can be shortened and the cost can be reduced, but also the thermal conductivity is high. Since the molding cycle can be shortened and the weight is lighter, there are many advantages in terms of attaching / detaching, transporting, and assembling the mold in the molding machine, and aluminum molds have been studied. ing.

However, aluminum molds (hereinafter, also simply referred to as "aluminum molds") are excellent in workability, but have lower hardness than steel materials, so that parts where metals come into direct contact with each other, for example, during molding. In a mold having a parting line surface or a sliding portion when the fixed mold member and the movable mold member are fitted by a strong impact, the sliding member, for example, the contact between the slide core portion surface and the mold surface. As a result, there is a problem that surface wear and galling occur.

Normally, aluminum is an active metal that combines with oxygen in the atmosphere to naturally form a thin aluminum oxide film on the surface. Since this aluminum oxide has corrosion resistance, it prevents the progress of corrosion, but the aluminum oxide film is destroyed by the impact received on the parting line surface as described above and the rubbing of the members on the sliding parts. Then, the corrosion progresses more rapidly than that part.

On the other hand, as a resin molded product manufactured by an injection molding die, for example, a housing of an OA device can be mentioned. Generally, from the viewpoint of safety, flame retardancy is required for the housing of OA equipment. In particular, strict flame retardancy is required for exterior parts such as copier covers. Therefore, as a material for the housing of OA equipment, resins such as acrylonitrile-butadiene-styrene (ABS) containing a flame retardant, modified polyphenylene ether, and polycarbonate are widely used. Examples of the flame retardant include inorganic compounds such as aluminum hydroxide and antimony trioxide, and halogen-based organic compounds. However, when a large amount of the flame retardant of the inorganic compound is added to the resin, the fluidity of the resin becomes low and the molding process is performed. The sex gets worse. In order to solve this problem, a bromine-based organic compound such as tetrabromobisphenol A is generally used as a flame retardant to be added to the resin. However, the halogen-based organic compound has a problem that it corrodes the mold because it generates a corrosive gas such as HBr by melting the resin. When the mold is corroded, burrs are generated on the molded product at the corroded part, which affects the quality of the product.

To solve the above problems, a method of forming a durable film on an aluminum mold has been proposed.

For example, an injection molding die in which iron-based plating is applied to the transfer wall surface of the fixed mold member constituting the cavity and the transfer wall surface of the movable mold member and the inner surface in contact with the molten resin is disclosed (see, for example, Patent Document 1). ). According to this method, it is said that smooth and efficient molding can be performed by using an aluminum mold having excellent workability and hardening it only in a specific place. In the surface treatment by iron-based plating, a film thickness of 10 μm or more is required in order to obtain sufficient mechanical strength to withstand practical use. As a result, there is a problem that it becomes difficult to control the size of the mold because the size of the mold changes by the amount of the film thickness before and after the film is formed.

Further, an injection molding die made of an aluminum alloy having a hard alumite film formed on a specific portion on the surface of the aluminum die is disclosed (see, for example, Patent Document 2). According to this method, in a mold component made of an aluminum alloy, it is possible to improve the wear resistance and galling resistance of the slide sliding surface, and a highly durable aluminum alloy injection molding mold is provided. It is said that it can be done. However, in forming a hard alumite film, electric discharge machining is difficult, machinability is extremely poor as compared with an aluminum alloy as a base material, and there is a problem in production efficiency. Further, it has a problem that it is technically difficult to form a hard alumite film with a thickness required only for the exposed part of the aluminum alloy for an aluminum mold that has been subjected to hard alumite processing. ..

Further, a method of immersing an aluminum alloy mold in a solution containing an organosilicon compound to form a boehmite layer on the mold surface and forming a siloxane bond with the aluminum surface is disclosed (see, for example, Patent Document 3). .). According to this method, it is said that corrosion resistance is improved by forming a siloxane bond with the boehmite layer. However, the method disclosed in Patent Document 3 is insufficient in terms of resistance to impact and sliding on the parting line surface, the slide core portion surface of the sliding portion, and the mold surface, and has specific flame retardancy. The resistance to corrosive gas such as HBr generated in the molding of the resin material including the material is also insufficient.

Japanese Patent No. 48544943 Japanese Unexamined Patent Publication No. 9-12325 Japanese Unexamined Patent Publication No. 9-300360

The present invention has been made in view of the above problems, and the problem to be solved thereof is that the film is made of an aluminum alloy, has excellent strength against impact and sliding during molding, and has excellent durability against molding resin. The present invention relates to an injection molding die, a method for manufacturing the same, and a method for manufacturing a resin molded product using the injection molding die.

As a result of diligent studies in view of the above problems, the present inventor is for injection molding in which a molten resin is injected into a cavity of a mold and the shape of the cavity is transferred to the resin to form a resin molded product. In the mold, the cavity is provided between the fixed mold member and the movable mold member, and at least one of the fixed mold member and the movable mold member is formed of an aluminum alloy, and the surface of the aluminum alloy is formed. We have found that it is possible to provide a mold for injection molding having a coating film formed of a specific compound containing aluminum, at least in part, and have arrived at the present invention.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. 1. It is an injection molding die that injects molten resin into the cavity of the mold and transfers the shape of the cavity to the resin to form a resin molded product.
The cavity is formed between the fixed type member and the movable type member, or between the fixed type member and the movable type member and the slide core constituting the sliding portion, and the molten resin is supplied to the cavity. It has a gate connected to the cavity and a runner connected to the gate.
At least one of the fixed member, the movable member, and the slide core is formed of an aluminum alloy.
A mold for injection molding, wherein at least a part of the surface of the aluminum alloy has a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum.

2. 2. The injection molding die according to item 1, wherein at least a part of the sliding portion or the parting line surface composed of the fixed mold member and the movable mold member has the coating film.

3. 3. The first item or the second item, wherein the sliding portion is composed of at least a first mold component composed of a slide core and a second mold component on which the slide core slides. Mold for injection molding.

4. The injection molding die according to any one of items 1 to 3, wherein the thickness of the coating film formed on the surface of the aluminum alloy is 10 μm or less.

5. A method for manufacturing an injection molding die according to any one of paragraphs 1 to 4, wherein the injection molding die is manufactured.
A cavity is formed between the fixed member and the movable member, or between the fixed member and the movable member and the slide core constituting the sliding portion.
In order to supply the molten resin to the cavity, a gate connected to the cavity and a runner connected to this gate are formed.
At least one of the fixed member, the movable member and the slide core is formed of an aluminum alloy.
A method for producing an injection molding mold, which comprises forming a film on at least a part of the surface of the aluminum alloy with a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum.

6. The method for manufacturing an injection molding die according to Item 5, wherein the coating film is formed by a chemical reaction on the surface of the aluminum alloy.

7. The injection molding product according to item 5 or 6, wherein a coating film is formed on at least a part of the sliding portion or a parting line surface composed of the fixed mold member and the movable mold member. Mold manufacturing method.

8. An extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the surface of the injection molding die, and the surface of the injection molding die or The method for manufacturing an injection molding die according to item 5 or 6, wherein the film is formed by raising a temperature of a part thereof.

9. An extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the sliding portion and the parting line surface, and sliding during molding trial operation. The method for manufacturing an injection molding die according to Item 7, wherein the film is formed by frictional heat generated by the mold.

10. The method for manufacturing an injection molding die according to Item 8, wherein the extreme pressure lubricant is removed from the surface of the injection molding die after forming a film using the extreme pressure lubricant. ..

11. The injection molding die according to Item 9, wherein the extreme pressure lubricant is removed from the sliding portion or the parting line surface after forming a film using the extreme pressure lubricant. Production method.

12. A method for producing a resin molded product, which comprises molding a resin material using the injection molding die according to any one of the items 1 to 4.

13. The method for producing a resin molded product according to Item 12, wherein the resin material contains a halogen-based flame retardant or a phosphorus-based flame retardant.

An injection molding die made of an aluminum alloy by the above means of the present invention, having a coating film on the surface having excellent strength against impact and sliding during molding and excellent durability against molding resin, and a method for manufacturing the same. It is possible to provide a method for manufacturing a resin molded product using the injection molding die.

Although the mechanism of expression and mechanism of action of the effects of the present invention have not been clarified, it is inferred as follows.

The injection molding die formed of the aluminum alloy of the present invention has good workability, which is a feature thereof, and takes advantage of the advantages that the manufacturing time and cost of the die can be shortened and parting. It is possible to solve the problem that the line surface and the sliding portion are worn, the aluminum oxide film on the surface is peeled off, and the surface is corroded by the gas derived from the resin used for molding.

Further, in order to improve durability (corrosion resistance), a pole selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is limited to the entire surface of the aluminum mold or the relevant portion. By applying a pressure lubricant and raising the temperature of the surface or a part of the injection molding mold, a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum is formed. Durability can be dramatically improved.

By forming the above-mentioned coating film having excellent durability on the surface of the aluminum mold, the surface becomes inactive and the resistance to corrosive gas generated from the molding resin or the like can be improved.

Further, since the coating film according to the present invention has a property of having higher lubricity than a normal aluminum oxide coating, when a fixed mold member and a movable mold member are fitted at the time of molding to form a cavity. It has the property that it does not easily come off from the surface of the aluminum mold due to impact or friction during sliding operations. In particular, by forming a coating film having the lubricity according to the present invention on the sliding sliding surface where the sliding operation is repeated, galling in the sliding portion can be prevented.

Further, such a protective effect on the surface of the aluminum mold is not permanent, and it is necessary to regenerate the coating film at an appropriate time. However, as in the case of metal plating treatment or alumite coating treatment, the aluminum mold is immersed in each treatment liquid. Since it is not necessary, a film to be regenerated can be easily formed, and the maintainability is excellent.

Schematic cross-sectional view showing an example of the overall configuration of the injection molding die of the present invention (Embodiment 1). Schematic cross-sectional view showing another example of the overall configuration of the injection molding die of the present invention (Embodiment 2).

The injection molding mold of the present invention is an injection molding mold for injecting a resin into a cavity of a mold and transferring the shape of the cavity to the resin to form a resin molded product. A cavity is formed between the fixed member and the movable member, or between the fixed member and the movable member and the slide core constituting the sliding portion, and is used to supply the molten resin to the cavity. It has a gate connected to the cavity and a runner connected to the gate, and at least one of the fixed member, the movable member, and the slide core is formed of an aluminum alloy, and the surface of the aluminum alloy is formed. At least a part of the above is characterized by having a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum. This feature is a technical feature common to or corresponding to the invention according to each of the following embodiments.

As an embodiment of the present invention, from the viewpoint of further exhibiting the effect intended by the present invention, it is particularly necessary to have the coating film on at least a part of the slide sliding surface or the parting line surface. By forming a coating film having lubricity on the slide sliding surface that is susceptible to sliding, it is difficult to peel off during sliding, and galling with the slide core or the like can be prevented.

Further, the effect of the present invention is that the slide sliding surface is composed of at least a first mold component composed of a slide core and a second mold component having a sliding portion on which the slide core slides. It is preferable in that it can be more expressed.

Further, by setting the thickness of the coating film formed on the surface of the aluminum alloy to 10 μm or less, it is possible to minimize the dimensional change of the aluminum mold due to the formation of the coating film, and the dimensional accuracy of the molded product and the mold can be minimized. The fitting accuracy can be maintained. Further, since the lubricity is determined by the surface of the mold, a sufficient coating effect can be exhibited when the coating thickness is 10 μm.

In the method for manufacturing a mold for ejection molding of the present invention, a cavity is formed between a fixed mold member and a movable mold member, and a gate connected to the cavity is used to supply the molten resin to the cavity. A runner connected to this gate is formed, at least one of the fixed member and the movable member is formed of an aluminum alloy, and at least a part of the surface of the aluminum alloy is a phosphoric acid compound of aluminum and a sulfur compound. It is characterized in that a film is formed by a compound or a chlorine-based compound.

Further, in the present invention, it is preferable to form a coating film by a chemical reaction on the surface of the aluminum alloy, because a thin film coating having a thickness of 10 μm or less can be stably formed according to the surface shape. ..

Further, an extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the surface of the injection molding mold to form the injection molding mold. The method of forming the coating film by raising the temperature of the surface or a part thereof is preferable. The effect of mold protection is not permanent and may reshape the coating on a regular basis. In the present invention, unlike metal plating and alumite coating, it is not necessary to immerse the aluminum mold in each treatment liquid, so that a coating that can be easily regenerated can be formed, and maintenance is also excellent. Is preferable.

Further, an extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the slide sliding surface and the parting line surface during a molding test run. It is preferable to form the coating film by the frictional heat generated by the sliding portion of the above, because the effect of the coating film can impart lubricity to the sliding portion and prevent galling of the sliding portion.

Further, it is preferable to remove the extreme pressure lubricant from the surface of the injection molding die after forming a film using the extreme pressure lubricant. This is because the formed film itself is chemically bonded to the surface of the aluminum mold and is not wiped off. By wiping off only the grease component of the extreme pressure lubricant, the grease component adheres to the resin molded product. Can be prevented.

Further, in the method for producing a resin molded product of the present invention, it is derived from the flame retardant that the injection molding mold of the present invention is applied to molding using a resin material containing a halogen-based flame retardant or a phosphorus-based flame retardant. It is preferable in that it can prevent the mold from being corroded by the gas.

Hereinafter, the present invention, its constituent components, and modes and embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the following description, "~" is used to mean that the numerical values described before and after it are included as the lower limit value and the upper limit value. Further, in the following description, the numbers described after each component represent the reference numerals of the components described in each figure.

<< Mold for injection molding >>
The injection molding die of the present invention is an injection molding die that injects a molten resin into a cavity of a mold and transfers the shape of the cavity to the resin to form a resin molded product.
The cavity is provided between the fixed member and the movable member, and has a gate connected to the cavity for supplying the molten resin to the cavity and a runner connected to the gate.
At least one of the fixed type member and the movable type member is formed of an aluminum alloy.
It is characterized in that at least a part of the surface of the aluminum alloy has a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum.

[Construction of injection mold]
Hereinafter, the configuration of the injection molding die of the present invention will be described with reference to the drawings.

[Embodiment 1]
FIG. 1 is a schematic cross-sectional view showing an example of the overall configuration of the injection molding die of the present invention, and shows an injection molding die (Embodiment 1) having a structure having no sliding portion.

The injection molding die 1 shown in FIG. 1 includes a fixed side substrate 7 and a movable side substrate 10, and by fitting the fixed side substrate 7 and the movable side substrate 10, a cavity 5 is formed between them. Will be done.

The fixed-side substrate 7 is fixed to the fixed-side mounting plate 6, and the movable-side substrate 10 is connected to the movable-side mounting plate 18 via a receiving plate 12 and a spacer block 13. A locating ring 4 is mounted on the fixed side mounting plate 6, and an injection cylinder (not shown) is connected to the locating ring 4. Further, a sprue bush 3 is mounted inside the locating ring 4 in the fixed side mounting plate 6. The sprue bush 3 penetrates the fixed side mounting plate 6 and extends into the fixed side substrate 7, and a sprue 20 serving as a supply flow path for the molten resin is formed inside the sprue bush 3. A runner L communicates with the sprue 20, and the runner L and the cavity 5 communicate with each other via a gate G. Here, a sprue lock pin 19 for removing the resin remaining in the sprue 20 after molding is arranged at the connection portion between the sprue 20 and the runner L.

The movable side substrate 10 connected to the movable side mounting plate 18 via the receiving plate 12 and the spacer block 13 can move in the direction of approaching and separating from the fixed side substrate 7, and during this operation, the movable side substrate can be moved. In order to align the 10 with respect to the fixed side substrate 7, the guide pin 9 provided on the movable side substrate 10 is slidably connected to the guide bush 8 provided on the fixed side substrate 7. Further, after the molding is completed in the cavity 5, the ejector pin 15 located at the lower part of the cavity 5 is raised to push up the molded product molded in the cavity 5 and release the mold. become. Here, the ejector pin 15 is mounted under the ejector blade 17 and is inserted into the insertion hole 25 formed as desired in the cavity 5 through the receiving plate 12 and the movable side substrate 10. It is preferable to form a coating film according to the present invention on the inner surface side of the movable side substrate 10 of the insertion hole 25 in order to prevent wear due to vertical movement of the ejector pin 15.

Then, by moving the lower 17 of the ejector blade in the direction close to the movable side mounting plate 18 by a predetermined stroke, the molded product in the cavity 5 is pushed up. A return pin 11 on which a return spring 14 is actuated is provided so that the lower 17 of the ejector blade rises to push up the molded product and then lowers to a position where it abuts on the movable side mounting plate 18. Reference numeral 1 is slidable in the insertion hole provided in the movable side template 10.

Further, in the present invention, the fitting surface between the fixed side substrate 7 and the movable side substrate 10 is referred to as a parting line surface PL.

The injection molding die 1 is configured as described above, and the injection molding die 1 is further provided with a heating means for heating or cooling the resin in the cavity 5 and cooling. It has the means. Here, as the heating means, a rod type or band type heater is generally used, and the cooling means is composed of water-cooled or air-cooled ones, and water provided inside the fixed-side substrate 7 and the movable-side substrate 10 is provided. Cooling water or the like is circulated through the holes 2 to cool the mold after molding.

The details of each part described above will be described.

The gate G shown in FIG. 1 is an inlet when the molten resin material flows into the cavity 5 of the mold from the runner L, and is a part that controls the flow and the molten state of the molten resin, and is the first of the molded products. It is located in a thick part. It is also a part where the unnecessary runner portion is separated from the molded product after molding. If the size is too small, sink marks are likely to occur, and if it is too large, residual distortion is likely to occur.

Further, the cavity 5 in the present invention means a gap in which a molded product is molded by a mold. Further, the runner L may refer to a concave portion of the mold itself. The runner L is a passage that guides the molten resin from the sprue bush 3 into the cavity 5 of the mold, and the size and shape are determined by the type of molding material. do. It is desirable to increase the runner L from the viewpoint of the fluidity of the molding material, but since the cooling time is long, it is usually made smaller than the cross section of the molded product and processed to a large size while testing.

Further, the sprue 20 refers to a passage for transferring the molten resin from the nozzle to the runner L.

Further, the sprue bush 3 is a path for transferring the molten plastic ejected from the nozzle, and refers to a cylindrical part to be fitted into a mold. It consists of a suitable pedestal for close contact between the tapered sprue hole and the injection molding machine nozzle. The diameter of the inlet must be 1 to 2 mm larger than the diameter of the tip of the nozzle, and the diameter of the inlet of the sprue 20 must be 0.5 to 1.0 mm larger than the nozzle diameter, otherwise the molten plastic will leak and it will be difficult to pull out the sprue 20. It ends up.

Further, the sprue lock pin 19 serves to attract the molded product when the tip of the pin is undercut and the mold is opened, and to pull out the sprue 20 from the sprue bush 3.

After opening the mold, the sprue lock pin 19 protrudes the sprue 20. It also has the role of removing the gas contained in the molten plastic.

By driving the movable side mounting plate 18 constituting the injection molding die 1 in a direction close to the fixed side mounting plate 6, the fixed side mold plate 7 and the movable side mold plate 10 are joined to each other, and a predetermined pressing force is applied. Molding is performed by the action of. In this state, an injection cylinder is connected to the locating ring 4, and the molten resin is supplied from the sprue 20 into the cavity 5 via the runner L and the gate G. In order to keep the molten resin in a high temperature state until it is sufficiently spread in the cavity 5, the fixed side substrate 7 and the movable side substrate 10 are held in a heated state by a heating means.

When the molten resin has spread throughout the cavity 5, heating by the heating means is stopped, cooling water is flowed through the water holes 2 by the cooling means, and cooling is started. When the cavity 5 drops to a predetermined temperature, the melted resin is solidified and molded. Therefore, the movable side substrate 10 is lowered and separated from the fixed side substrate 7 to release the mold, and then the ejector pin 15 is raised to take out the molded product, and the ejector pin 15 is further acted on by the action of the return pin 11. To lower. This is called one cycle, and by repeating this operation, resin molding is sequentially performed.

Here, since heating and cooling are repeated in the cavity 5 when the resin is continuously injection-molded, in order to shorten the cycle time of heating and cooling, the material of the injection molding mold 1 is used. It is necessary to use one with high thermal conductivity. Further, in order to smoothly perform mold clamping and mold opening with a light load, the weight of the injection molding die 1, particularly the movable side substrate 10, the receiving plate 12, the spacer block 13, and the like must be reduced. Moreover, since a high molding pressure acts on the cavity 5, the runner L, which is the flow path of the molten resin, the gate G, etc., each part constituting the injection molding die 1 also requires mechanical strength. Will be done. From these points, among the parts constituting the injection molding die 1, at least the fixed side template 7 and the movable side template 10 constituting the resin passage are made of aluminum alloy. Further, the receiving plate 12 and the spacer block 13 are also preferably made of an aluminum alloy from the viewpoint of weight reduction. However, it is desirable that the fixed side mounting plate 6 and the movable side mounting plate 18 are made of steel in order to maintain the strength.

As the aluminum alloy, for example, Al-Mg-based, Al-Zn-Mg-based, etc. are preferably used in order to have strength against the molding pressure acting on the fixed-side template 7 and the movable-side template 10. Al-Cu-Mg system, that is, duralumin can also be used.

The aluminum alloy described above is a soft metal and has a lower hardness than iron. However, the aluminum alloy applied to the present invention has features that it is easy to process due to its low hardness, the mold manufacturing time is short, and the manufacturing cost is also reduced.

However, the solid aluminum alloy is exposed on the surface of the fixed side template 7 and the movable side template 10 which are the transfer surfaces, and the wall surface of the runner 12 and the gate 13 which form the flow path of the molten resin. If this is the case, the durability will be insufficient, such as the wall surface being worn at an early stage when the molten resin is supplied.

Here, the thermal conductivity of aluminum is 240 W ・ m ^-1・ K ^-1 , while the thermal conductivity of carbon steel generally used as a steel mold is 48.5 W ・ m -1 ・ K ^-1. It is ^-1. That is, since the thermal conductivity of the aluminum mold is about 5 to 6 times higher than that of the steel mold, it is possible to heat and cool more quickly by using the aluminum mold. And the energy consumption is also reduced. Further, since the specific gravity of aluminum is 2.70 and that of steel is about 7.85, the weight of the entire molding die 1 is reduced, its assembly is easy, and the die is fastened and molded. It can be opened smoothly with a light load.

[Embodiment 2: Injection molding mold having a sliding portion unit]
FIG. 2 is a schematic cross-sectional view (embodiment 2) showing an example of an injection molding die having a sliding portion in the overall configuration of the injection molding die of the present invention.

In the present invention, it is preferable that the slide sliding surface is composed of at least a first mold component composed of a slide core and a second mold component having a sliding portion on which the slide core slides. Further, it is preferable that at least a part of the slide sliding surface has a coating film according to the present invention.

The basic overall configuration of the injection molding die having a sliding portion is almost the same as that of the injection molding die 1 described with reference to FIG. 1, but a movable nest 21 is provided, and the movable nest 21 has a gate. G and runner L are connected to one side.

A sliding portion SP is arranged on the other surface side of the movable nest 21, and the sliding portion SP is composed of a locking block 23, a slide core 22, and an angular pin 24. At 26, the inner surface of the movable nest 21 is rubbed by the slide core 22 in and out.

Therefore, it is effective to form a coating film according to the present invention on the inner surface of the movable nest 21.

The injection molding die having a sliding portion as shown in FIG. 2 can be used for molding a resin molded product having an undercut shape.

In the production of a resin molded product using a normal injection molding die as shown in FIG. 1, the molding resin is injected into the cavity after the mold composed of the fixed mold member and the movable mold member is closed. Then, after the molding is completed, the product is extruded by the ejector pin.

On the other hand, in undercut, that is, in the molding of a resin product having a shape that cannot be removed by the movement of a normal molding mold, the slide core 22 is used to open and close the mold. FIG. 2 shows an opening / closing method using the angular pin 24.

As shown in FIG. 2, the angular pin 24 is arranged obliquely with respect to the fixed side. When the mold opens, the slide core 22 moves along the diagonally arranged angular pins 24. In this state, the undercut can be removed.

While pushing down the angular pin 24, the slide core 22 is slid to the position shown in FIG. Next, it is formed between the fixed mold member and the movable mold member and the slide core constituting the sliding portion, and after the molten resin is supplied to the cavity and molded, when the mold starts to open, it is set diagonally. The regular pin 24 lowers the slide core 22. Finally, when the mold is fully opened, the slide core 22 forms the resin in the cavity 5 and then moves the ejector pin 15 up and down to separate it from the cavity 5. Also at this time, the ejector pin is separated from the cavity 5. Since the inner surfaces of the movable nesting 21 and the movable nesting 21 are subject to friction, it is effective to provide the coating film according to the present invention also inside the insertion hole 25.

[Formation of film]
In the present invention, at least one of the fixed mold member and the movable mold member constituting the injection molding mold described above is formed of an aluminum alloy, and at least a part of the surface of the aluminum alloy is a phosphoric acid compound of aluminum. It is characterized by having a film formed of a sulfur-based compound or a chlorine-based compound.

The fixed mold member and the movable mold member constituting the injection molding mold in the present invention are the fixed mold member forming the cavity 5 and the inner wall portion of the movable mold member, the inner wall portion of the sprue 20, and the parting line surface PL. , The runner L portion, the gate G portion, the insertion hole 25 in the movable nest 21, the slide sliding surface 26 in sliding, and the like.

The injection molding mold of the present invention is characterized in that at least a part of the surface of the aluminum alloy has a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum.

The method for forming the coating film according to the present invention is selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant on the surfaces of the fixed mold member and the movable mold member of the aluminum mold. After applying the extreme pressure lubricant, the surface or part of the injection molding mold is heated to a predetermined temperature, or the frictional heat due to sliding during the molding test run is used to create the space between the aluminum surface and the extreme pressure lubricant. It is a method of forming a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum by causing a chemical reaction in the above.

Specifically, in the method for manufacturing an injection molding die of the present invention, the surface of the injection molding die is selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant. It is a preferable form to form the coating film by applying an extreme pressure lubricant and heating the surface or a part of the injection molding die to raise the temperature.

Further, in another manufacturing method of the injection molding die of the present invention, a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant and a chlorine-based extreme pressure lubricant are applied to the slide sliding surface or the parting line surface. It is preferable to apply an extreme pressure lubricant selected from the agents to form the film by frictional heat due to sliding during the molding test run.

<Extreme pressure lubricant>
Extreme-pressure lubricants (also called extreme-pressure additives) are used to make metals two-sided, for example, to reduce friction and wear between fixed mold members and movable mold members that make up injection molding dies, and to prevent seizure. It is an additive used in.

The extreme pressure lubricant is a component that not only imparts extreme pressure lubricity (oil film strength) but also improves mold releasability. In the present invention, the extreme pressure lubricant is a phosphoric acid-based extreme pressure lubricant. , It is preferable to apply an extreme pressure lubricant selected from a sulfur-based extreme pressure lubricant and a chlorine-based extreme pressure lubricant.

Generally, extreme pressure agents are substances containing sulfur, chlorine, phosphorus, etc., such as sulfide oils and fats, sulfide esters, sulfates, chlorinated hydrocarbons, lead naphthenate, and sulfur, phosphorus, etc. in the same molecule. Compounds containing two or more elements in chlorine can be used.

An example of a typical extreme pressure lubricant is shown below.

(1) Phosphoric acid-based extreme pressure lubricant: phosphate ester (for example, tricresyl phosphate, lauryl acid phosphate, etc.), subphosphate ester (for example, tributyl phosphate, dilauryl phosphate, etc.), thiophosphate ester (for example, thiophosphate ester). Zinc dialkyldithiophosphate, zinc diallyldithiophosphate, etc.), amine salts of phosphate esters, zinc dialkyldithiocarbamate, etc.

(2) Sulfur-based extreme pressure lubricant: olefin sulfide, mineral oil sulfide, dialkyl sulfide, dialkyl disulfide, fatty sulfide ester, dibenzyl disulfide, alkyl polysulfide, olefin polysulfide, zantic sulfide, etc.

(3) Chlorine-based extreme pressure lubricant: methyltrichlorostearate, chlorinated paraffin, etc.

Regarding other extreme pressure lubricants and specific methods for applying them to aluminum molds, for example, JP-A-2001-219236, JP-A-2011-093963, JP-A-2011-105831, and JP-A-2012. The contents described in Japanese Patent Publication No. -11038 can be referred to.

<< Manufacturing method of resin molded products >>
The present invention is characterized in that a resin is molded using the injection molding die of the present invention, and further, a method for manufacturing a resin molded product using a resin material containing a halogen-based flame retardant or a phosphorus-based flame retardant. By applying it to, it exerts an excellent effect.

(Resin material)
The resin material applicable to the present invention is not particularly limited as long as it can be thermally molded, and for example, aromatic polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polyamide 4, polyamide 6 and the like. Polyamide 7, Polyamide 8, Polyamide 11, Polyamide 12, Polyamide 66, Polyamide 69, Polyamide 610, Polyamide 611, Polyamide 612, Polyamide 6T and other aliphatic and aromatic polyamide homopolymers, Polyamide 6/66 copolymer, Polyamide With aliphatic and aromatic polyamide copolymers such as 6/12 copolymer, polyamide 6 / 6T copolymer, polyamide 6I / 6T copolymer, and xylylene diamine such as polymethoxylylen adipamide (polyamide MXD6). Semi-aromatic polyamide resin obtained by polycondensation reaction with aliphatic dicarboxylic acid, polyolefin resin such as polyethylene and polypropylene, polystyrene, styrene-acrylonitrile copolymer (AS resin), styrene- (meth) acrylic acid copolymer, Polyamide-based resins such as styrene-methyl methacrylate copolymer, rubber-modified polystyrene (HIPS), acrylonitrile-butadiene-styrene copolymer (ABS resin), methyl methacrylate-butadiene-styrene copolymer (MBS resin), polycarbonate Examples thereof include a resin, a polyacetal resin, a polyphenylene ether resin, a polyphenylene sulfide resin, a liquid crystal polymer, a polysulfone resin, and a polymethylacrylate resin, and these can be used in combination of two or more.

(Flame retardants)
In the present invention, the resin material is a system containing a halogen-based flame retardant or a phosphorus-based flame retardant, and the effect of the coating film according to the present invention can be fully exerted.

Examples of the phosphorus-based flame retardant include phosphoric acid ester compounds such as sulphite ester, phosphoric acid ester and phosphonic acid ester, and among these, it is particularly preferable to use phosphoric acid ester.

Specific examples of the phosphite ester include triphenylphosphite, tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, distearylpentaerythritol diphosphite, and bis (2). , 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite and the like.

Specific examples of the phosphate ester include triphenyl phosphate, tris (nonylphenyl) phosphate, tris (2,4-di-t-butylphenyl) phosphate, distearylpentaerythritol diphosphate, and bis (2,6-di-). t-Butyl-4-methylphenyl) pentaerythritol diphosphate, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphate, tributyl phosphate, bisphenol A bis-diphenyl phosphate, aromatic condensed phosphate, etc. Can be mentioned. Examples of the aromatic condensed phosphoric acid ester include 1,3-phenylene bis (di2,6 xylenyl phosphate), bisphenol A bis (diphenyl phosphate) and 1,3-phenylene bis (diphenyl phosphate). ..

Specific examples of the phosphonic acid ester include dimethyl benzenephosphonate and benzenephosphonic acid ester.

Examples of the halogen-based flame retardant include polybromodiphenyl ether, tetrabromobisphenol-A, brominated epoxy oligomer, brominated polycarbonate oligomer and the like.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto. In addition, although the display of "%" is used in the examples, it represents "mass%" unless otherwise specified.

<< Production of resin molded products >>
[Manufacturing and evaluation of resin molded product 1: comparative example]
(Making mold A for injection molding)
An injection molding die 1 having the configuration shown in FIG. 1 was produced.

<Constituent materials for molds>
Both the fixed side template and the movable side template are made of aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Molding resin material>
Polybutylene phthalate containing a brominated flame retardant was used.

<Molding conditions for resin molded product 1>
Injection pressure: 150MPa
Holding pressure: 50 MPa
Cycle time: 40 seconds Mold temperature: 80 ° C
<result>
Corrosion occurs on the PL surface of the mold in about 100 cycles due to the gas derived from the brominated flame retardant. Further, the depth of the corroded uneven portion was about 30 μm, the resin leaked from the parting line surface and burrs were generated, and the resin molded product 1 was impossible as a product.

The term "1 cycle" as used herein is as described above, and means a cycle until one molded product is manufactured.

[Manufacturing and evaluation of resin molded product 2: comparative example]
Using the injection molding die A, the resin molded product 2 was produced in the same manner except that polycarbonate containing a phosphorus-based flame retardant was used as the molding resin material.

<result>
Corrosion occurs on the PL surface of the mold in about 100 cycles due to the gas derived from the phosphorus flame retardant. Further, the depth of the corroded uneven portion was about 25 μm, the resin leaked from the parting line surface and burrs were generated, and the resin molded product 2 was impossible as a product.

[Manufacturing and evaluation of resin molded product 3: Comparative example]
(Making mold B for injection molding)
An injection molding die B having the structure shown in FIG. 2 was produced.

<Constituent materials for molds>
The fixed-side template, the movable-side template, and the movable nest having an insertion hole and a sliding sliding surface were constructed using aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Molding resin material>
Polybutylene phthalate containing a brominated flame retardant was used.

<Molding conditions for resin molded product 3>
Injection pressure: 150MPa
Holding pressure: 70 MPa
Cycle time: 50 seconds Mold temperature: 80 ° C
<result>
In about 100 cycles, the sliding operation and corrosion due to the gas derived from the brominated flame retardant occurred inside the movable nest having the insertion hole and the slide sliding surface, and the resin molded product 3 was impossible as a product. rice field.

[Manufacturing and evaluation of resin molded product 4: comparative example]
Using the injection molding die B, the resin molded product 4 was produced in the same manner except that polycarbonate containing a phosphorus-based flame retardant was used as the molding resin material.

<result>
In about 100 cycles, the sliding operation and corrosion due to the gas derived from the brominated flame retardant occurred inside the movable nest having the insertion hole and the slide sliding surface, and the resin molded product 4 was impossible as a product. rice field.

[Manufacturing and Evaluation of Resin Molded Product 5: The Present Invention]
(Making mold C for injection molding)
An injection molding die C having the structure shown in FIG. 1 was produced.

<Constituent materials for molds>
Both the fixed-side template and the movable-side template were constructed using aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Formation of film>
A phosphoric acid-based extreme pressure lubricant containing a phosphoric acid ester was applied to the surface side of the fixed-side mold and the movable-side mold for forming the parting line surface PL of the injection-molding die produced above. Then, each template was put into a furnace at 100 ° C. and heated for 1 hour. By this operation, the extreme pressure additive and the aluminum on the parting line surface chemically reacted to form a film made of a phosphoric acid compound of aluminum on the parting line surface, and an injection molding die C was produced.

<Molding resin material>
Polybutylene phthalate containing a brominated flame retardant was used.

<Molding conditions for resin molded product 5>
Injection pressure: 150MPa
Holding pressure: 50 MPa
Cycle time: 40 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no corrosion due to the gas derived from the brominated flame retardant was observed on the PL surface of the mold even after 1000 cycles, and a good resin molded product 5 could be obtained.

[Manufacturing and Evaluation of Resin Molded Product 6: The present invention]
(Making a mold D for injection molding)
An injection molding die D having the configuration shown in FIG. 1 was produced.

<Constituent materials for molds>
Both the fixed-side template and the movable-side template were constructed using aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Formation of film>
A sulfur-based extreme pressure lubricant containing an olefin sulfide was applied to the surface side of the fixed-side mold and the movable-side mold for forming the parting line surface PL of the injection-molding die produced above. Then, each template was put into a furnace at 100 ° C. and heated for 1 hour. By this operation, the extreme pressure additive and the aluminum on the parting line surface chemically reacted to form a film made of a sulfur-based compound of aluminum on the parting line surface, and an injection molding die D was produced.

<Molding resin material>
Polybutylene phthalate containing a brominated flame retardant was used.

<Molding conditions for resin molded product 6>
Injection pressure: 150MPa
Holding pressure: 50 MPa
Cycle time: 40 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no corrosion was observed on the PL surface of the mold due to the gas derived from the brominated flame retardant even after 1000 cycles, and a good resin molded product 6 could be obtained.

[Manufacturing and Evaluation of Resin Molded Product 7: The Present Invention]
(Making mold E for injection molding)
An injection molding die E having the configuration shown in FIG. 1 was produced.

<Constituent materials for molds>
Both the fixed-side template and the movable-side template were constructed using aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Formation of film>
A chlorine-based extreme pressure lubricant containing chlorinated paraffin was applied to the surface side of the prepared mold for injection molding that forms the parting line surface PL of the fixed side mold plate and the movable side mold plate. Then, each template was put into a furnace at 100 ° C. and heated for 1 hour. By this operation, the extreme pressure additive and the aluminum on the parting line surface chemically reacted to prepare a mold E for injection molding in which a film made of a chlorine-based compound of aluminum was formed on the parting line surface.

<Molding resin material>
Polybutylene phthalate containing a brominated flame retardant was used.

<Molding conditions for resin molded product 7>
Injection pressure: 150MPa
Holding pressure: 50 MPa
Cycle time: 40 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no corrosion was observed on the PL surface of the mold due to the gas derived from the chlorine-based flame retardant even after 1000 cycles, and a good resin molded product 7 could be obtained.

[Manufacturing and Evaluation of Resin Molded Product 8: The Present Invention]
In the production of the resin molded product 5, the resin molded product 8 was produced in the same manner except that polycarbonate containing a phosphorus-based flame retardant was used instead of polybutylene phthalate containing a brominated flame retardant as the molding resin material.

<result>
Even in a system using polycarbonate containing a phosphorus-based flame retardant, corrosion due to gas derived from the chlorine-based flame retardant was not observed on the PL surface of the mold even after 1000 cycles due to the effect of film formation, and it was a good resin molded product. I was able to get 8.

[Manufacturing and Evaluation of Resin Molded Product 9: The Present Invention]
(Making mold F for injection molding)
An injection molding die F having the structure shown in FIG. 2 was produced.

<Constituent materials for molds>
The fixed-side template, the movable-side template, and the movable nest having an insertion hole and a sliding sliding surface were constructed using aluminum alloy A7075. All other plate members (fixed side mounting plate, receiving plate, spacer block, ejector blade top, ejector blade bottom and movable side mounting plate) were made of S55C (steel material).

<Formation of film>
A sulfur-based extreme pressure lubricant containing olefin sulfide is applied to the inner surface side of the insertion hole (ejector pin sliding surface) and slide sliding surface (slide sliding surface) in the movable nest of the injection molding die produced above. Applied. Next, as a trial run of the mold, the ejector pin of the insertion hole and the slide sliding portion of the slide sliding surface were slid. The sulfur-based extreme pressure additive and the aluminum of each sliding part chemically react with each other due to the frictional heat during sliding, and a film made of a sulfur-based compound of aluminum is formed on the sliding part to prepare a mold F for injection molding. bottom.

<Molding resin material>
Polycarbonate containing a phosphorus-based flame retardant <Molding conditions for resin molded product 9>
Injection pressure: 150MPa
Holding pressure: 70 MPa
Cycle time: 50 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no sliding operation or corrosion due to phosphorus-based flame retardant-derived gas was observed inside the movable nest having an insertion hole and a sliding sliding surface even after 1000 cycles, and good resin molding was performed. Item 9 was obtained.

[Manufacturing and Evaluation of Resin-Based Product 10: The Present Invention]
(Making mold G for injection molding)
In the production of the injection molding mold F, the film forming material was changed from a sulfur-based extreme pressure lubricant containing a sulfide olefin to a phosphoric acid-based extreme pressure lubricant containing a phosphoric acid ester, and phosphoric acid of aluminum was used. A film composed of a system compound was formed to prepare a mold G for injection molding.

<Molding resin material>
Polycarbonate containing a phosphorus-based flame retardant <Molding conditions for resin molded product 10>
Injection pressure: 150MPa
Holding pressure: 70 MPa
Cycle time: 50 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no sliding operation or corrosion due to phosphorus-based flame retardant-derived gas was observed inside the movable nest having an insertion hole and a sliding sliding surface even after 1000 cycles, and good resin molding was performed. I was able to obtain the product 10.

[Manufacturing and Evaluation of Resin Molded Product 11: The Present Invention]
(Making mold H for injection molding)
In the production of the injection molding die F, the film forming material is changed from a sulfur-based extreme pressure lubricant containing olefin sulfide to a chlorine-based extreme pressure lubricant containing chlorinated paraffin, and a chlorine-based compound of aluminum is used. A mold H for injection molding was produced by forming a coating film composed of the above.

<Molding resin material>
Polycarbonate containing a phosphorus-based flame retardant <Molding conditions for resin molded product 11>
Injection pressure: 150MPa
Holding pressure: 70 MPa
Cycle time: 50 seconds Mold temperature: 80 ° C
<result>
Due to the effect of film formation, no sliding operation or corrosion due to phosphorus-based flame retardant-derived gas was observed inside the movable nest having an insertion hole and a sliding sliding surface even after 1000 cycles, and good resin molding was performed. Item 11 could be obtained.

[Manufacturing and Evaluation of Resin Molded Product 12: The Present Invention]
In the production of the resin molded product 9, the resin molded product 12 was produced in the same manner except that the molded resin material was changed to polybutylene phthalate containing a brominated flame retardant.

<result>
Due to the effect of film formation, no sliding operation or corrosion due to the gas derived from the brominated flame retardant was observed inside the movable nest having an insertion hole and a sliding sliding surface even after 1000 cycles, and good resin molding was performed. Item 12 could be obtained.

(summary)
As described above, at least one of the fixed type member and the movable type member is formed of an aluminum alloy, and at least a part of the slide sliding surface or the parting line surface is made of an aluminum phosphoric acid-based compound or sulfur-based compound. Alternatively, the injection molding die of the present invention having a film formed of a chlorine-based compound can be compared with the comparative example in that the parting line surface of the die, the insertion hole and the slide can be obtained even after continuous resin molding. A good resin molded product could be obtained without being affected by the corrosive gas derived from the flame retardant inside the movable nest having a sliding surface.

The injection molding die of the present invention is made of an aluminum alloy, has a coating film having excellent strength against impact and sliding during molding and excellent durability against molding resin, and is manufactured by an injection molding die. As the resin molded product, for example, it can be suitably used for manufacturing a housing of an OA device.

1 Injection molding mold 2 Water hole 3 Sprue bush 4 Locating ring 5 Cavity (molding part)
6 Fixed side mounting plate 7 Fixed side template 8 Guide pin bush 9 Guide pin 10 Movable side template 11 Return pin 12 Receiving plate 13 Spacer block 14 Return spring 15 Ejector pin 16 Ejector blade top 17 Ejector blade bottom 18 Movable side mounting plate 19 Sprue lock pin 20 Sprue 21 Movable nest 22 Slide core 23 Locking block 24 Angular pin 25 Insertion hole (ejector pin sliding surface)
26 Slide sliding surface G Gate L Runner PL Parting line surface SP Sliding part

Claims (13)

It is an injection molding die that injects molten resin into the cavity of the mold and transfers the shape of the cavity to the resin to form a resin molded product.
The cavity is formed between the fixed type member and the movable type member, or between the fixed type member and the movable type member and the slide core constituting the sliding portion, and the molten resin is supplied to the cavity. It has a gate connected to the cavity and a runner connected to the gate.
At least one of the fixed member, the movable member, and the slide core is formed of an aluminum alloy.
A mold for injection molding, wherein at least a part of the surface of the aluminum alloy has a film formed of a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum. The injection molding die according to claim 1, wherein at least a part of the sliding portion or the parting line surface composed of the fixed mold member and the movable mold member has the coating film. The first or second aspect of the present invention, wherein the sliding portion is composed of at least a first mold component composed of a slide core and a second mold component on which the slide core slides. Mold for injection molding. The injection molding die according to any one of claims 1 to 3, wherein the thickness of the coating film formed on the surface of the aluminum alloy is 10 μm or less. A method for manufacturing an injection molding die according to any one of claims 1 to 4, wherein the injection molding die is manufactured.
A cavity is formed between the fixed member and the movable member, or between the fixed member and the movable member and the slide core constituting the sliding portion.
In order to supply the molten resin to the cavity, a gate connected to the cavity and a runner connected to this gate are formed.
At least one of the fixed member, the movable member and the slide core is formed of an aluminum alloy.
A method for producing an injection molding mold, which comprises forming a film on at least a part of the surface of the aluminum alloy with a phosphoric acid-based compound, a sulfur-based compound, or a chlorine-based compound of aluminum. The method for manufacturing an injection molding die according to claim 5, wherein the coating film is formed by a chemical reaction on the surface of the aluminum alloy. The injection molding according to claim 5 or 6, wherein the coating film is formed on at least a part of the sliding portion or the parting line surface composed of the fixed mold member and the movable mold member. Mold manufacturing method. An extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the surface of the injection molding die, and the surface of the injection molding die or The method for manufacturing an injection molding die according to claim 5 or 6, wherein the film is formed by heating a part of the temperature. An extreme pressure lubricant selected from a phosphoric acid-based extreme pressure lubricant, a sulfur-based extreme pressure lubricant, and a chlorine-based extreme pressure lubricant is applied to the sliding portion and the parting line surface, and sliding during molding trial operation. The method for manufacturing an injection molding die according to claim 7, wherein the film is formed by frictional heat generated by the metal. The method for manufacturing an injection molding die according to claim 8, wherein the extreme pressure lubricant is removed from the surface of the injection molding die after forming a film using the extreme pressure lubricant. .. The injection molding die according to claim 9, wherein the extreme pressure lubricant is removed from the sliding portion or the parting line surface after forming a film using the extreme pressure lubricant. Production method. A method for manufacturing a resin molded product, which comprises molding a resin material using the injection molding die according to any one of claims 1 to 4. The method for producing a resin molded product according to claim 12, wherein the resin material contains a halogen-based flame retardant or a phosphorus-based flame retardant.

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