JP3044027B2 - Production method of resin molded products by injection molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the production of a molded article in injection molding in which a molded article is formed by injecting a resin into a space between a male mold and a female mold arranged opposite to each other and cooling and solidifying the resin. More particularly, the invention relates to a production method for producing molded articles such as nameplates.

[0002]

2. Description of the Related Art As a method of molding a molded article mainly using a resin, press working and injection molding are known. Among them, injection molding is widely used because it has advantages such as the ability to obtain a molded article having a complicated shape as compared with press working, low cost, and high yield. . In this injection molding method, a male-female mold and a female mold (these male and female molds are collectively referred to as “molds” as necessary) are formed in a shape conforming to the outer shape of a molded product. Forming a space portion (hereinafter, this space portion is referred to as “molding space portion”),
A molded product is formed by injecting a molten resin into the molding space and cooling and solidifying the resin.

[0003] The injection molding method can be roughly classified into a method of directly injecting the resin into the molding space and a method using a so-called runner system based on a method of injecting the resin into the molding space of the mold. Of these, the method using a runner system is an injection method for so-called multi-chamfering, in which a plurality of molding spaces are arranged side by side, an injection path called a runner is provided at the center position, and gates are provided at a plurality of locations of the runner. In this case, an injection path having a smaller diameter than the runner is provided. Then, the molten resin is injected into the runner, and further injected into the molding space through the gate.

[0004]

In recent years, there has been an increasing demand for thinner housings and various nameplates of electronic devices as much as possible in order to reduce the weight and thickness. When molding a thin molded product such as a name plate by an injection molding method,
Since the molding space is thin, the pressure loss inside the molding space is large, and the fluidity of the resin in the molding space is poor. Particularly, in the injection molding method using the runner system as described above, since the inflow path of the resin into the molding space is limited to a small number of narrow paths such as gates, there is a possibility that the resin does not reach the entire molding space. high. Therefore, in the injection molding method using the conventional runner system, it has been difficult to form a thin plate.

Further, the conventional method has various problems from the viewpoint of production efficiency. In other words, when the runner system cannot be used as described above, it is conceivable to directly inject the resin by linking the resin injection holes to the molding space, but since this method cannot perform multi-panning, Production efficiency was poor. In addition, as a result of the inability to perform multi-face removal, it is difficult to collectively perform post-processing such as painting on a plurality of molded products, and it becomes necessary to perform post-processing for each molded product. It was inefficient.
In addition, because it is difficult to form such a thin plate, it may be unavoidable to form a molded product such as a name plate into a thick shape.However, such a thick name plate is attached because of its strong elasticity. It is difficult to hold for a long time in a state of being curved along the surface. Therefore, it is necessary to individually form a name plate having a shape corresponding to the curvature of the attaching surface, and the production efficiency is also low in this respect.

[0006] Even if the multi-planning can be performed using the runner system, especially when the molded product is thin, the runner often protrudes above the molded product. If it is left unprinted, it will not be possible to print on the molded product, and after all, it will be necessary to separate the runner and carry out post-processing for each molded product, and the production efficiency is also low in this regard.

Further, the conventional method has various problems from the viewpoints of processing accuracy and appearance of a molded product. For example, in the above-mentioned runner system, the contact surface between the male mold and the female mold is located on the side of the molded product, and a linear projection called a parting line is formed on the side surface of the molded product after the resin is solidified. Part is left. Since this parting line impairs the appearance of a molded product, a production method that does not leave a parting line has been demanded. Conventionally, the molded product after solidification is ejected from the female mold by protruding with a pin, but when a resin such as colored ABS is used, the molded product is protruded against the molded product and pressed against the pin. Was whitened and traces remained, which sometimes impaired the appearance of the molded article. Further, when a resin such as a transparent material is used, it is impossible to decorate the back surface or the like because the protrusions on the back surface leave marks of pins and the like.

Alternatively, in the conventional runner system, it is difficult to improve the printing precision and the cutting precision because the device for positioning the molded product with respect to the base in the printing step and the cutting step has not been devised. For this reason, laser cutting that requires particularly high positioning accuracy cannot be performed, and press cutting (gate cutting such as a rotary saw blade type) is also performed on a molded product formed of a high-strength resin such as an acrylic resin. Machine, cutting with a nipper, etc.). However, the higher the strength of the resin, the more likely it is for cracks to occur at the time of cutting. Furthermore, in the conventional runner system,
Since the resin is injected through a narrow-diameter injection path such as a gate, the pressure (stress) generated by the injection is concentrated in a narrow area around the gate, and only the density of the resin around the gate is applied to other parts. In contrast, there were cases where the overall density and the like became non-uniform. For example, when a transparent resin disposed outside the liquid crystal screen for protection of the liquid crystal screen is molded by a conventional runner system, the density of a portion close to the gate is different from the density of other portions. However, when viewing the liquid crystal screen from various angles, there is a problem that only the portion near the gate becomes black and the screen becomes invisible.

The present invention has been made in view of the problems of the conventional method for producing a resin molded product by injection molding, and enables resin molding to be performed easily and precisely, and enables production of a plurality of products. It is an object of the present invention to provide a method for producing a resin molded product by injection molding, which can improve the properties and can provide an even better appearance.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the conventional method of producing a resin molded product by injection molding, the present invention according to the first aspect of the present invention provides a male mold and a female mold which are arranged to face each other. A method for producing a resin molded product by injection molding, wherein a molten resin is injected into a space between the mold and the resin through an injection hole, and the resin is solidified to form a molded product. A plurality of molding spaces that are arranged side by side in conformity with the outer shape of the molded product, and an auxiliary space that communicates with the plurality of molding spaces and the injection hole and surrounds the entire periphery of the plurality of molding spaces. A first step of configuring, a second step of injecting the molten resin into the auxiliary space through the injection hole, and injecting the resin into each of the plurality of molding spaces through the auxiliary space And a third step of performing There.

The present invention described in claim 2 provides the present invention according to claim 1.
In the present invention, in the first step, the auxiliary space portion is disposed between the plurality of the molding space portions arranged in parallel, and the plurality of molding space portions arranged in the auxiliary space portion are arranged in the auxiliary space portion. It is characterized in that it surrounds the entire periphery of the part.

The present invention according to claim 3 provides the present invention according to claim 1.
In the first aspect of the present invention, in the first step, the auxiliary space portion is provided with a flow promoting portion that promotes the flow of the resin in the auxiliary space portion by increasing the thickness of the auxiliary space portion. It is configured as a feature.

The present invention described in claim 4 provides the present invention as defined in claim 1.
In the present invention described in any one of Items 3 to 3, in the first step, the auxiliary space portion is provided with a flow restricting portion that controls the flow of the resin in the auxiliary space portion by reducing the thickness of the auxiliary space portion. It is configured as a feature.

The present invention according to claim 5 provides the present invention according to claim 1.
In the present invention described in any one of Items 4 to 4, in the first step, the auxiliary space portion may be provided with a positioning portion that forms a positioning hole for regulating positions of the auxiliary space portion and the molding space portion. It is configured as a feature.

The present invention described in claim 6 is the first invention.
In the present invention according to any one of the first to fifth aspects, in the first step, an air vent for discharging gas in the molding space and the auxiliary space to the outside of the space is formed so as to communicate with the auxiliary space. It is configured as a feature.

The present invention described in claim 7 is the first invention.
In the present invention described in any one of the first to sixth aspects, in the first step, the contact surface between the male mold and the female mold is located only on the side of the auxiliary space.

The present invention described in claim 8 is the first invention.
In the present invention according to any one of the first to seventh aspects, after the third step, a fourth step of inserting a protruding pin into the auxiliary space and releasing the resin solidified in the molding space and the auxiliary space is performed. It is characterized by having.

The present invention described in claim 9 provides the present invention according to claim 8.
In the present invention, after the fourth step, the resin discharged to the outside of the molding space portion and the auxiliary space portion is arranged on a base, and the guide projection provided on the base is positioned by the positioning. A fifth position fixing the relative position between the resin and the base by inserting the resin into the positioning hole formed by the portion;
And a block having a shape corresponding to the molding space is provided on the base so as to be vertically movable, and the base of the resin injected and solidified into the molding space by the vertical movement of the block is provided. The upper and lower positions are adjustable.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, the resin is formed by multi-layering, and after the fifth step, the resin is disposed on the base. A sixth step of multifacetedly applying a predetermined surface treatment and / or a backside treatment (for example, a surface treatment for a colored resin and a front or backside treatment for a transparent resin) to the resin, and / or the base And a seventh step of multiply cutting the resin disposed at a predetermined dimension.

The present invention according to claim 11 is the invention according to claim 10, wherein in the seventh step, the resin is injected into the molding space and solidified, and It is configured to be separated into the auxiliary resin injected into the space and solidified.

According to a twelfth aspect of the present invention, in the tenth or eleventh aspect of the present invention, in the seventh step, the multi-plane cutting is performed by a laser.

According to a thirteenth aspect of the present invention, in any one of the tenth and eleventh aspects of the present invention, before or after the sixth step, a release sheet comprising an adhesive layer and a release paper is attached to the adhesive layer. And bonding the resin to the back surface of the resin through the second step, and in the seventh step, cutting the resin while leaving the release paper.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a method for producing a resin molded product by injection molding according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view conceptually showing the configuration of the injection molding machine. In the present embodiment, the thin casing 10 of the electronic device is molded by the injection molding method. FIG. 15 shows a front view of the housing 10 before assembly.
As shown in FIG. 15, the housing 10 includes a pair of components 10.
a, 10b, these parts 10a,
10b is simultaneously formed on multiple sides by a pair of molds. In the following, the injection molding result is simply referred to as a “molded product” as necessary.

The injection molding method according to the present embodiment is generally the same as the conventional one, and as shown in FIG. 1, a pair of dies (two-plate dies, a female dies 1 and a male dies 2) arranged opposite to each other. The melted resin 4 is injected into the molding space 3 between them, and the resin 4 is cooled and solidified to form a molded product. That is, the resin pellets 7 are put into the cylinder 6 via the hopper 5, and the resin pellets 7 are melted by shearing heat and / or heating by the screw 8 in the cylinder 6. The molten resin 4 is injected under high pressure into the molding space 3 between the female mold 1 and the male mold 2 to cool and solidify the resin 4, and then the female mold 1 and the male mold 2 are opened and molded. The product is released by extruding the product with the ejector 9.
Thereafter, roughly, the molded product is subjected to a surface treatment, cut into predetermined dimensions, and assembled. In addition, as the resin 4, ABS
(Acrylonitrile Butadiene Styrene), PC (Polycar
bonate), PC / ABS, ASA, acrylic (hard, soft), magnesium, nylon resin, noryl resin (hard, soft).

Next, the female mold 1, the male mold 2, and the molding space 3 between them will be described. 2 and 4 are front views of the female mold 1 and the male mold 2, respectively, and FIGS. 3 (a) to 3 (d).
5A to 5D are sectional views taken along arrows AA to DD in FIG. 4, respectively, and FIGS. 6A to 6D are sectional views taken along arrows AA to DD in FIG. a) to (d) each show FIG.
It is sectional drawing which shows the state which superposed the corresponding part of (a)-(d) and FIG.5 (a)-(d). In addition, the up, down, left, and right directions in the reference emphasis state of FIGS.

As shown in FIGS. 2 and 3, the female mold 1 is formed in a rectangular shape in the same manner as in the prior art, and has a reference surface 11 at its four circumferential ends, which is in direct contact with the male mold 2. . The inner part surrounded by the reference plane 11 includes a part 10a of the housing.
A concave portion 12 having a shape adapted to the external shape of the component 10b and a concave portion 13 having a shape adapted to the external shape of the component 10b are formed, and the concave portion 12 has a second shape adapted to the external shape of the IC chip holding portion 10c shown in FIG. Two concave portions 12a are formed. As shown in FIGS. 2 and 3, an injection hole 14 is formed as a through hole at the upper, lower, left, and right center positions of the female mold 1, and the resin 4 from the cylinder 6 in FIG. Is done. The female mold 1 is further provided with auxiliary concave portions 15, 16, a regulating convex portion 17, a promoting concave portion 18, and an air vent 19, which will be described later.

On the other hand, the male mold 2 is formed in a square shape having a width and a height corresponding to the female mold 1 as shown in FIGS. Barrel reference plane 21
Is provided. The reference surface 21 is formed with convex portions 22 and 23 projecting toward the female mold 1. The convex portion 23 further protrudes toward the female mold 1 side, and is provided with a second convex portion 23a adapted to the outer shape of the holding portion 10c of the IC chip shown in FIG. 15, and a groove portion 24 adapted to the shape of the rib 10d. Have been.
The rib 10d is used as a partition for intercepting an electromagnetic wave that separates the drive unit and the control unit held inside the housing 10 from each other. Further, a plurality of short columnar convex portions 25 are provided around the convex portions 22 and 23.

As shown in FIG. 6, when the female mold 1 and the male mold 2 are overlapped so that their reference surfaces 11 and 21 are in contact with each other, the protrusion 2 is provided in the recess 12.
3. The projection 23a is arranged in the recess 12a, and the projection 22 is arranged in the recess 13 respectively. A molding space 3 is formed between them. The height of this molding space 3,
The width and the thickness of the molded product (in this embodiment, the case 1
0 corresponds to the predetermined height, width, and thickness of the component 10a, 10b). Therefore, by injecting and solidifying the resin 4 into the molding space 3, a molded product having a predetermined size can be obtained.

Here, as shown in FIG.
Auxiliary recesses 15 and 16 which are shallower than these recesses 12 and 13 are formed around the periphery of the recess. As shown in FIG. 6, an auxiliary space 31 is formed between the female mold 1 and the male mold 2 formed by forming the auxiliary concave portions 15 and 16 in this manner. This auxiliary space 31
Are continuously arranged so as to surround the entire upper, lower, left, and right peripheries of the molding space 3, and the upper, lower, left, and right peripheries of the molding space 3 are covered by the auxiliary space 31. The process up to the formation of the molding space 3 and the auxiliary space 31 by the polymerization of the mold is the first step in the present method).

The auxiliary space 31 is in communication with the molding space 3 at all portions in contact with the molding space 3, and the auxiliary space 31 has, as shown in FIG.
The injection hole 14 communicates. Therefore, the resin 4 injected from the injection hole 14 is first injected into the auxiliary space 31 (second step), and is injected into the molding space 3 via the auxiliary space 31 (third step). In particular, since the auxiliary space portion 31 is arranged on the entire circumference of the molding space portion 3, the resin is transferred from the auxiliary space portion 31 into the molding space portion 3 at any of the upper, lower, left, and right sides of the molding space portion 3. 4 can be injected. Therefore, the resin 4 can flow into the molding space 3 from all directions of the molding space 3, and even if the molding space 3 is thin, the resin 4 can easily and uniformly flow into the molding space 3. Therefore, injection molding of a thin molded product is possible. In addition, since the resin 4 can flow from all directions in this manner, the injection pressure (stress) applied to the resin 4 becomes uniform as a whole, and the density and the like of the resin 4 can be made uniform. Therefore, for example, even when a transparent resin for protecting the liquid crystal screen is molded, the density and the like of the transparent resin can be made uniform as a whole. Can be made almost completely uniform, so that the visibility of the liquid crystal screen is not hindered. Although illustration is omitted,
A so-called slug well is formed in a portion of the auxiliary space 31 communicating with the injection hole 14.

FIG. 7 is a longitudinal sectional view corresponding to FIG. 6D, and shows a state in which the resin 4 is injected into the molding space 3 and the auxiliary space 31. After a predetermined time has elapsed from this state, the resin 4 injected into the auxiliary space 31 is also cooled and solidified integrally with the resin 4 injected into the molding space 3. The resin 4 injected into the auxiliary space 31 and solidified is cut and removed as described later. Hereinafter, if necessary, the entire resin in a state of being injected into the auxiliary space portion 31 and the molding space portion 3 and solidified integrally is used as the in-process resin 3 in order to distinguish them.
2. Among the resins separated from the in-process resin 32 in the post-processing, the resin injected into the molding space 3 and solidified is formed into a molded product (the components 10a, 10
b), the resin injected into the auxiliary space portion 31 and solidified is referred to as an auxiliary resin 33. 10 is a rear view of the in-process resin 32 (the surface in contact with the female mold 1 is the front of the in-process resin, the surface in contact with the male mold 2 is the back of the in-process resin, the same applies hereinafter), FIG.
10A to 10D are cross-sectional views taken along arrows AA to DD in FIG.

In this embodiment, as described above, since the pair of components 10a and 10b of the housing 10 are formed in multiple faces, the component 10a is formed when the female mold 1 and the male mold 2 are superposed. The forming space 3 for forming the part 10b and the forming space 3 for forming the part 10b are arranged side by side. An auxiliary space portion 31 is also arranged between the molding space portions 3 arranged side by side, and both of the molding space portions 3 are interposed via the auxiliary space portion 31.
By injecting the resin 4 into the resin, a multi-plane can be formed as shown in FIG.

As shown in FIG. 6, the auxiliary space portion 31 is provided with a flow promoting portion 34 for promoting the flow of the resin 4 in the auxiliary space portion 31 by increasing the thickness of the auxiliary space portion 31. ing. As shown in FIG. 2, the flow promoting portion 34 is formed by providing the female mold 1 with a promoting concave portion 18 which is continuous with the injection hole 14 and deeper than the auxiliary concave portions 15 and 16. This flow promotion part 3
4 is formed along a direction in which the fluidity of the resin 4 in the auxiliary space 31 is to be increased. The direction in which the fluidity is desired to be enhanced is usually the injection hole 14 and the position farthest from the injection hole 14 (the farthest position) among the positions where the resin 4 is injected.
It is the direction that connects Here, the thickness of the flow promoting portion 34,
The width and length are determined by the fluidity of the resin 4 (determined by the material and temperature of the resin), the distance from the injection hole 14 to the farthest position, and the magnitude of the flow resistance of the resin 4 due to the unevenness of the mold. Is determined so that the resin 4 flows at least to all parts of the molding space 3 most uniformly. Particularly, in the present embodiment, the molding space 3 between the concave portion 13 and the convex portion 22 is formed.
Since the molding space portion 3 between the concave portion 12 and the convex portion 23 has more irregularities and higher flow resistance of the resin 4 than the concave portion 12,
The flow promoting portion 34 is formed in a direction toward the molding space 3 between the projection 23 and the convex portion 23. In addition, the starting point of the flow promoting part 34 is not limited to the injection hole 14, but may be an arbitrary position as the starting point.

The flow promoting section 34 is connected to the auxiliary space 3
By appropriately arranging the resin 1, the fluidity of the resin 4 can be increased in any direction, so that the resin 4 can be uniformly injected into the entire space. Flow promotion part 3
As shown in FIGS. 10 and 11, the resin 4 flowing into the resin 4 becomes a thicker resin 33a than the molded product.
Since a is separated from the molded product as a part of the auxiliary resin 33, it does not affect the molded product. In this embodiment, the auxiliary concave portion 15 is formed to be slightly deeper than the auxiliary concave portion 16 as is apparent particularly in FIG. This is because the molding space 3 between the concave portion 12 and the convex portion 23 has more irregularities and the flow resistance of the resin 4 is higher as described above. This is to allow more resin 4 to flow.
In this sense, the entire auxiliary space portion 31 formed by the auxiliary concave portion 15 functions as the above-described flow promoting portion 34.

Further, as shown in FIG. 6, the auxiliary space portion 31 is provided with a flow restricting portion 35 for restricting the flow of the resin 4 in the auxiliary space portion 31 by reducing the thickness of the auxiliary space portion 31. ing. As shown in FIG. 2, the flow restricting portion 35 is formed by providing the female mold 1 with a thin regulating convex portion 17 protruding from the auxiliary concave portions 15 and 16 toward the male mold 2. The flow restricting portion 35 is disposed at a position where the flowability of the resin 4 in the auxiliary space 31 is to be reduced. The position where the fluidity is desired to be reduced is, for example,
This is a path from the vicinity of the injection hole 14 or from the injection hole 14 to the molding space portion 3 with less unevenness. In such a position,
If the fluidity of the resin 4 is high while the fluidity of the resin 4 is too high, the fluidity of the resin 4 reaching the molding space 3 having many irregularities may be hindered, so that the fluidity of the resin 4 needs to be reduced. However, the position is not limited to such a position.
The flow restricting portions 35 can be arranged at all positions where the flowability of the fluid is desired to be reduced. Here, the thickness of the flow regulating portion 35,
The width and the length are determined based on the fluidity of the resin 4 (determined by the material and temperature of the resin) and the like.
Is determined so that the resin 4 flows most uniformly in all the portions of.

The flow restricting portion 35 is connected to the auxiliary space 3
By appropriately arranging the resin 1, the fluidity of the resin 4 can be reduced in any direction, so that the resin 4 can be uniformly injected into the entire space. The resin 4 that has flowed into the flow restricting portion 35 is thinner than the molded product.
3b, the resin 33b is separated from the molded product as a part of the auxiliary resin 33, and thus does not affect the molded product.

As shown in FIG. 6, a positioning portion 36 for regulating the positions of the auxiliary space 31 and the molding space 3 (the entire position of the in-process resin 32) is provided in the auxiliary space 31.
Is provided. As shown in FIG. 4, the positioning portion 36 is formed by providing the male mold 2 with a plurality of short cylindrical protrusions 25 projecting toward the female mold 1 from the reference surface 21. The positioning portion 36 prevents the inflow and solidification of the resin 4, so that a plurality of positioning holes 33 c are formed in the in-process resin 32 as shown in FIG. 10. The positioning holes 33c are through holes, and position the auxiliary space 31 and the molding space 3 with respect to the base 70 (positioning of the in-process resin 32) in post-processing after injection molding.
Used to perform The specific usage of the positioning holes 33c will be described later. By appropriately arranging the positioning section 36 in the auxiliary space section 31, positioning in each processing step can be easily performed, and processing accuracy and processing efficiency are improved. In particular, in the present embodiment, since the positioning portion 36 is disposed in the auxiliary space portion 31,
Since the positioning hole 33c is separated from the molded product as a part of the auxiliary resin 33, there is an advantage that the molded product is not affected.

In general, when injecting a resin into a space, it is necessary to discharge gas in the space out of the mold.
For this reason, in this embodiment, as shown in FIG. 2, an air vent 19 for discharging gas in the molding space 3 and the auxiliary space 31 is formed to communicate with the auxiliary recesses 15 and 16. It is formed so as to communicate with the space 31. The air vent 19 is formed as a small-diameter space portion connecting the last place where the resin 4 flows into the auxiliary space portion 31 and an arbitrary portion outside the female mold 1, and forms the inside of the molding space portion 3 and the auxiliary space portion. The gas pushed out by the resin 4 injected into the inside 31 passes through the air vent 19 and the female mold 1
It is discharged outside. The diameter and the number of the air vents 19 are determined according to the volumes of the molding space 3 and the auxiliary space 31 and the speed at which the gas is to be discharged so that the gas can be discharged smoothly.

Although the air vent itself for discharging gas out of the mold was formed by the conventional injection molding method, the air vent was conventionally connected to the molding space 3. Therefore, if the gas is not completely discharged for some reason, the gas may remain in the molding space 3 and generate bubbles, burns, burrs, or the like in the molded product. However, when the air vent 19 is communicated with the auxiliary space 31 instead of the molding space 3 as in the present embodiment,
Even when the gas is not completely exhausted and bubbles are generated, the bubbles are formed in the auxiliary resin 33 instead of the molded product and separated from the molded product in the post-processing. Therefore, there is no possibility that a trouble due to residual gas is caused in the molded product. Particularly in the thin molded article as in this embodiment, the air vent 19 is effective because the air bubbles and the like have a large adverse effect, and since such obstacles can be removed in this way, it is necessary to use a resin that generates a large amount of gas such as a soft acrylic resin. It becomes possible. FIGS. 10 and 11 show burnt spots 33 caused by bubbles.
d.

Generally, as a result of the resin 4 entering the contact surface between the female mold 1 and the male mold 2 and solidifying, a parting line is formed on the side surface of the molded product. However, in this embodiment, as shown in FIG. 7, the contact surface between the female mold 1 and the male mold 2 is located only on the side of the auxiliary space 31, and only contacts the auxiliary space 31. , Is not in contact with the molding space 3. Therefore, the injected resin 4 is the female mold 1 and the male mold 2
Parting line 33 generated by entering the contact surface with
e is formed only on the peripheral surface of the auxiliary resin 33 as shown in FIGS. 10 and 11, and does not impair the appearance of the molded product.

After the resin 4 injected by the first to third steps described above is solidified, the male mold 2 is released from the female mold 1 as shown in FIG. 8, and further shown in FIG. Thus, the in-process resin 32 after solidification is released from the female mold 1 (fourth step). The release in the fourth step is performed by a plurality of protruding pins 9a of the ejector 9.
Each protruding pin 9a is, as shown in FIGS.
It projects from the female mold 1 toward the male mold 2 and presses the in-process resin 32. Here, since the plurality of protruding pins 9a, 9a are arranged only at positions corresponding to the auxiliary space 31 side, their tips press only the auxiliary resin 33 and do not touch the molded product. Therefore, as shown in FIGS. 10 and 11, the protrusion mark 33f generated by whitening due to the pressing of the protrusion pin 9a occurs only in the auxiliary resin 33, and does not impair the appearance of the molded product.

After the completion of the fourth step, FIGS.
In-process resin 32 is completed. In addition, when the thickness of each part of the in-process resin 32 molded by the present applicant is given as a reference value,
The auxiliary resin 33 is 1.0 mm (the side formed by the auxiliary concave portion 15) and 0.8 mm (the side formed by the auxiliary concave portion 16), the resin 33a is 1.6 mm, the resin 33b is 0.3 mm,
The parts 10a and 10b are 0.3 mm.

The released resin 32 is placed on a base 70 for post-processing. FIG. 12 is a plan view of the base 70, and FIG.
3 is a cross-sectional view taken along the line AA of FIG. 12, and FIG. 14 is a cross-sectional view of a state where the in-process resin 32 is mounted on the base 70 of FIG. As shown in FIGS. 12 to 14, the base 70 is provided with the in-process resin 3.
It is formed to have a width slightly larger than 2 (in FIG. 12, the outline of the in-process resin 32 is shown by imaginary lines), and a plurality of guide projections 71 are provided on the mounting surface thereof. Then, in a state where the in-process resin 32 is placed on the base 70, each guide projection 71 is inserted into each positioning hole 33c, and
, The relative position of the in-process resin 32 in the horizontal plane is fixed (fifth step). In this state, each guide projection 71 does not protrude to the front side of the in-process resin 32, and does not hinder the surface treatment of the in-process resin 32. Of course, each positioning hole 33c is formed at a position and a diameter corresponding to each guide projection 71. When using multiple bases in multiple post-processing,
A plurality of types of positioning holes 33c having different positions and diameters may be formed in accordance with each base.

Then, post-processing is performed on the in-process resin 32. This post-processing is performed in the order of surface treatment (sixth step), cutting (seventh step), and assembling (eighth step). Of these, the surface treatment is applied to the parts 10a and 10b of the in-process resin 32, and is applied, plated, dipped, printed (screen, offset, and pat), taped with a shielding property, deposited, hot stamped, and diamond stamped. , Injection, caustic treatment and the like. In particular, since electromagnetic shielding is important in the housing 10 of an electronic device, an electromagnetic shielding paint is applied. The details of each of these surface treatments are the same as in the prior art and will not be described.

Also, the outer shape can be removed from the in-process resin 32 to the component 10.
a, 10b are separated by laser processing, Thomson processing, die pressing, engraving blade processing (including thermal processing), high frequency processing, and the like. The outline removal may be performed before the above-described surface treatment. However, by performing the outline treatment after collectively performing the surface treatment on a plurality of components 10a and 10b, a more efficient surface treatment can be performed. . Then, the housing 10 is formed by assembling the components 10a and 10b with each other. Therefore, first, a circuit board or the like formed in another process is sandwiched between the components 10a and 10b, and the pair of components 10a and 10b
Is assembled integrally with double-sided tape, heat bond, glue printing, locking claw, screwing, heat caulking, high frequency sealing, clipping, and retaining. Needless to say, when assembling by means of locking claws or retainer fastening, these locking claws and the like may be integrally injection-molded.

Next, a second embodiment of the present invention will be described. FIG. 16 is a front view of the female mold 40, and FIGS.
(D) is a female mold 40 as a cross-sectional view taken along arrows AA to DD in FIG.
FIG. 18 is a sectional view showing a state where a portion corresponding to 0 is superimposed;
FIG. 17C is a sectional view showing a state where the resin 4 is injected into the molding space 60 and the auxiliary space 61 between the female mold 40 and the male mold 50 in FIG. 17C, and FIG. 19 is a sectional view of the female mold 40 in FIG. From male mold 50
FIG. 20 is a sectional view showing a state where the mold is released, and FIG.
21 is a cross-sectional view of a state in which the in-process resin 41 is released, FIG. 21 is a rear view of the in-process resin 41, and FIGS. 22 (a) to 22 (d) are cross-sectional views taken along arrows AA to DD in FIG. Is shown. The configuration that is not particularly described is the same as that of the first embodiment. In the present embodiment, a case will be described in which the thin and thick rectangular name plate 42 shown in FIG. 28 is formed by an injection molding method.

As shown in FIGS. 16 and 17, the female mold 40 has a reference surface 43 at the four circumferential ends. This reference plane 4
A plurality of recesses 44 having a shape conforming to the outer shape of the name plate 42 are formed in an inner portion surrounded by 3.
By forming a plurality of the concave portions 44 in this manner, a plurality of concave portions can be formed. As shown in FIGS. 16 and 17, an injection hole 45 is formed as a through hole at the center position of the female mold 1 in the upper, lower, left, and right directions. The female mold 1 has an auxiliary recess 47,
An accelerating concave portion 46 which is a concave portion deeper than the auxiliary concave portion 47 and a groove-shaped air vent 48 communicating with the auxiliary concave portion 47 are provided. On the other hand, as shown in FIG. 17, the male mold 50 in the present embodiment is formed in a substantially planar shape except for a convex portion 51 described later. That is, the male mold 50 is the female mold 40
And has a flat continuous surface as a whole.

By polymerizing such a female mold 40 and a male mold 50, a molding space 60 is formed therebetween as shown in FIG. In addition, since the auxiliary concave portion 47 as shown is provided in the female mold 1, an auxiliary space portion 61 surrounding the entire periphery of the molding space portion 60 is formed (first step). Then, by injecting the resin 4 into the injection hole 45, the resin 4 first flows into the auxiliary space 61 (second step), and further flows from the auxiliary space 61 into the molding space 60 (third step).

In the first step, as shown in FIG.
The flow promoting portion 62 is formed by increasing the thickness of the fluid. Accordingly, the flowability of the resin 4 injected from the injection hole 45 is increased in the flow promoting portion 62, and more resin 4 flows in the direction of the flow promoting portion 62.
21 and 22 show a thick resin 48a formed of the resin 4 flowing into the flow promoting section 62. In this embodiment, since the female mold 40 and the male mold 50 have a symmetrical shape and the fluidity of the resin 4 is symmetrical, the flow promoting portion 6
2 (promoting concave portion 46 forming the flow promoting portion 62) is formed in a symmetrical shape from the injection hole 45 to the four corners.

In the first step, as shown in FIG. 17, a positioning portion 52 composed of a plurality of convex portions 51 provided on the male mold 50 is provided. A plurality of positioning holes 48 are formed in the auxiliary resin 48.
b, 48b are formed. The in-process resin 41 molded by using the female mold 40 and the male mold 50 as shown in FIG.
As shown in FIGS. 1 and 22, the plurality of name plates 42 are surrounded by the auxiliary resin 48 and are integrally solidified.

After the resin is solidified, the mold is released as shown in FIGS. 18 to 20 (fourth step). Also in this embodiment, as shown in FIGS. 16, 17, and 20, a plurality of projecting pins 9a, 9 projecting from the female mold 40 toward the male mold 50.
This is performed by pressing the in-process resin 41 at a. Also in this case, since the protruding pin 9a is arranged only at a position corresponding to the auxiliary space 31 side, as shown in FIGS. 21 and 22, the protruding trace 48c is formed only on the auxiliary resin 48 and impairs the appearance of the molded product. Nothing.

The in-process resin 41 released is placed on a base 80 for post-processing. FIG. 23 is a plan view of the base 80, FIG.
4 (a) and 4 (b) are cross-sectional views taken along line AA of FIG.
It is BB arrow sectional drawing. As shown in FIGS. 23 and 24, the base 80 is provided with a plurality of guide projections 81, 81, and although not shown, the base 80 has
Each guide protrusion 81 is inserted into each positioning hole 48b in a state in which the
The relative position in the horizontal plane is fixed (fifth step). Here, on the base 80, a plurality of block portions 82, 82 slightly wider than the molded products are arranged at positions corresponding to the plurality of molded products to be multi-faced. These block portions 82, 82 are housed in a recess 83 provided in the base 80 so as to be freely taken in and out.
By interposing a spacer member 84 made of an arbitrary material such as metal or paper between the bottom surface of the block 3 and the block portion 82, the protrusion height of the block portion 82 from the base 80 can be adjusted. In FIG. 24B, a spacer member 84 is sandwiched only between the concave portion 83 and the block portion 82 on the right side of the paper of the two block portions 82, and the block portion 82 is higher than the base 80 by a height H. This shows a state in which it protrudes. By adjusting the protrusion height of the block portion 82 in this manner, the interval between the in-process resin 41 mounted on the base 80 and a processing device such as a printing device in post-processing can be adjusted for each molded product, Post-processing can be performed more precisely.

After the in-process resin 41 is thus mounted on the base 80, screen printing is performed on the back surface of the in-process resin 41 (sixth step). FIG. 25 is a rear view of the in-process resin 41 after screen printing, and FIG. 26 is a cross-sectional view taken along the line AA of FIG. As shown in FIGS. 25 and 26, a portion 63 corresponding to the name plate 42 on the back of the in-process resin 41 is printed with a character-shaped print 63 of “ABC”. Prints 64 of different colors are applied.

After printing, the molded product is cut (seventh step). This cutting is performed using a laser 90. FIG. 27 is a longitudinal sectional view conceptually showing cutting by the laser 90. As shown in FIG. 27, the in-process resin 41 placed on the base 80 is irradiated with a laser beam by a laser 90, and the auxiliary resin 48 is separated from the plurality of name plates 42, and at the same time, the plurality of name plates 42 Are separated from each other. FIG. 28 is a front view of the name plate 42.

In this embodiment, the laser 9
Since the cutting is performed by using 0, a molded article having a complicated shape can be easily cut, and the cut surface is improved as compared with press cutting or the like. In particular, it is not necessary to perform press cutting (including cutting with a gate cutter and nipper) on molded products molded with high-strength resin such as acrylic resin, so that cracks are prevented from occurring on molded products. Can be. In the cutting by the laser 90, it is important to accurately maintain the relative position of the in-process resin 41, which is the object to be cut, with respect to the laser 90. In the present embodiment, as described above, the positioning hole 48b and the guide protrusion 81
This positioning is achieved by coordination with. That is, since the positioning can be performed accurately, the laser 90
Cutting can be performed.

Next, a third embodiment of the present invention will be described. 29 is a longitudinal sectional view of the in-process resin 41 to which the release sheet 100 is attached, FIG. 30 is a front view after press cutting in FIG. 29, and FIGS. 31 (a) and (b) are A-
FIG. 3 is a cross-sectional view as viewed in the direction of arrow A, and a cross-sectional view as viewed in the direction of arrow BB. In this embodiment, the configuration that is not particularly described is the same as that of the second embodiment. In the present embodiment, after the first to sixth steps of the second embodiment, cutting is performed in a seventh step different from the second embodiment.

That is, after the sixth step is completed, as shown in FIG.
0 is affixed. The release sheet 100 is a release paper 101
Is coated with an adhesive layer 102. In this state, cutting is performed by laser processing, Thomson processing, die pressing, engraving blade processing (including thermal processing), high frequency processing, or the like. In this cutting, a so-called half-blanking is performed, and a part other than the molded product is basically cut and removed. However, as shown in FIG. 31, the release paper 101 is completely left without being cut, and The adhesive layer 102 between the article and the release paper 101 is also left. Therefore, FIG.
As shown at 0 and 31, a plurality of molded products are aligned on the surface of the release paper 101, which makes counting at the time of delivery and handling in the assembly process much easier.

Although the first to third embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, but may be implemented in various forms within the scope of the technical idea. These different modes will be described below. First, the molded article molded by the present method is not limited to the one described in the above embodiment, but may be an arbitrary shaped molded article. Naturally, the shapes of the female mold and the male mold are also arbitrarily changed according to the shape of the molded product. Furthermore, in the first embodiment, the description has been given assuming that the two parts 10a and 10b are molded at one time, but it is possible to take more parts as many as long as the resin flows into the molding space. .

In the above embodiment, the auxiliary space is arranged in a uniform shape around the molding space, but may be unevenly arranged according to the fluidity of the resin. Further, in the above embodiment, the flow restricting portion is provided by providing the restricting convex portion on the female mold, but the restricting convex portion may be provided on the male mold. Similarly, a flow promoting portion may be provided by providing a promoting concave portion in a male mold instead of a female mold. Alternatively, both the female mold and the male mold may be provided with a regulating convex portion or a promoting concave portion. In addition, the number, position, and shape of the flow restricting section, the flow promoting section, the positioning section, and the air vent may be arbitrarily determined under the above-described conditions.

[0060]

As described above, according to the first aspect of the present invention, a plurality of molding spaces are formed so as to conform to the outer shape of a molded product, and the entire periphery of the plurality of molding spaces is surrounded. The auxiliary space portion, the molten resin is injected into the auxiliary space portion through the injection hole, and the resin is injected into each of the plurality of molding space portions through the auxiliary space portion. The resin can flow into the molding space from all directions of the molding space, and the resin can easily flow uniformly into the molding space even if the molding space is thin. Efficient injection molding of thin molded products becomes possible. Further, for example, since the product nameplate can be formed to be thin, the elasticity of the nameplate can be adjusted appropriately, and the nameplate can be held in a curved state according to the sticking surface. Therefore, it is not necessary to form a nameplate every time the curvature of the attachment surface changes, and one nameplate can be attached to various attachment surfaces, thereby improving production efficiency. In addition, since the resin can flow from all directions, the injection pressure (stress) applied to the resin becomes uniform as a whole, and the density and the like of the resin can be made uniform. Therefore, for example, even when a transparent resin for protecting the liquid crystal screen is molded, the density and the like of the transparent resin can be made uniform as a whole. Can be made almost completely uniform, so that the visibility of the liquid crystal screen is not hindered.

Further, according to the present invention, an auxiliary space portion is arranged between a plurality of molding space portions arranged in parallel, and the entire circumference of each of the plurality of molding space portions arranged in parallel in the auxiliary space portion. By injecting the resin into each of the plurality of molding spaces through such an auxiliary space portion, even more efficient multi-panning can be performed through the auxiliary space portion even in thin-wall molding, and the production efficiency can be improved. Can be greatly improved.

Further, the present invention according to claim 3 is characterized in that the auxiliary space portion is provided with a flow promoting portion for increasing the thickness of the auxiliary space portion to promote the flow of the resin in the auxiliary space portion. Since the fluidity of the resin can be increased in any direction, the resin can be uniformly injected into the entire space. In particular, since the flow promoting portion is provided in the auxiliary space portion, the resin that flows into the flow promoting portion and solidifies is separated from the molded product as a part of the auxiliary resin.
It is possible to perform more precise thin-wall molding without affecting the molded product.

Further, according to the present invention, the auxiliary space portion is provided with a flow restricting portion for restricting the flow of the resin in the auxiliary space portion by reducing the thickness of the auxiliary space portion. Since the fluidity of the resin can be reduced in any direction, the resin can be uniformly injected into the entire space. In particular, since the flow restricting section is provided in the auxiliary space, the resin that has flowed into the flow restricting section and solidified is separated from the molded product as a part of the auxiliary resin.
It is possible to perform more precise thin-wall molding without affecting the molded product.

According to a fifth aspect of the present invention, the auxiliary space portion is provided with a positioning portion for forming a positioning hole for regulating the positions of the auxiliary space portion and the molding space portion. In addition, since the positioning hole is easily separated from the molded product as a part of the auxiliary resin, the thinner molding can be performed without affecting the molded product.

Further, according to the present invention, since the air vent for discharging the gas in the molding space and the auxiliary space to the outside of the space is formed in communication with the auxiliary space, the gas is completely discharged. Even if bubbles are generated, the bubbles are formed not in the molded product but in the auxiliary resin and are separated from the molded product in post-processing. Therefore, it is possible to perform more accurate thin-wall molding without causing an obstacle due to the residual gas in the molded article.

Further, according to the present invention, in the first step, the contact surface between the male mold and the female mold is located only on the side of the auxiliary space, so that the parting line can be formed. Even if it occurs, the parting line is formed not in the molded product but in the auxiliary resin and is separated from the molded product in the post-processing, so that the molded product is not affected, and a more precise and good appearance thin-wall molding can be performed. It can be carried out.

According to the present invention, in the fourth step, after the third step, a projecting pin is inserted into the auxiliary space to release the solidified resin in the molding space and the auxiliary space. By having the above, even if a protrusion mark is generated by whitening due to the pressing of the protrusion pin, the protrusion mark is formed on the auxiliary resin instead of the molded product and is separated from the molded product in post-processing, so that the molded product is affected. This makes it possible to perform more precise and good-looking thin-wall molding.

According to a ninth aspect of the present invention, after the fourth step, the resin discharged to the outside of the molding space and the auxiliary space is arranged on the base and provided on the base. A fifth step of fixing the relative position between the resin and the base by inserting the guide protrusion into the positioning hole formed by the positioning part, and the base has a block part having a shape corresponding to the molding space part. The relative distance between the molded product and the post-processing device can be adjusted by adjusting the vertical position of the resin injected into the molding space and solidified on the base by the vertical movement of the block part. It can be adjusted for each product, and post-processing can be performed more precisely.

According to the tenth aspect of the present invention, the resin is formed in multiple faces, and after the fifth step, a predetermined surface treatment is applied to the resin placed on the base in multiple faces. By providing the sixth step and / or the seventh step of cutting the resin placed on the base into predetermined dimensions on multiple sides, it is possible to perform the surface treatment and cutting on a plurality of molded products at once. The production efficiency can be greatly improved.

Further, the present invention according to claim 11 provides:
In the seventh step, the resin is separated into a molded product injected into the molding space and solidified, and an auxiliary resin injected and solidified into the auxiliary space to be formed by the flow promoting portion and the flow regulating portion. Since the solidified resin, positioning holes, scorch, parting line and protrusion marks are separated from the molded product together with the auxiliary resin, it is possible to perform thinner molding with higher precision and good appearance without affecting the molded product. it can.

Further, the present invention according to claim 12 provides the seventh aspect of the present invention.
In this step, by performing the multi-plane cutting with a laser, it is possible to easily cut even a molded article having a complicated shape, and the cut surface is improved as compared with press cutting or the like. In particular, it is not necessary to perform press cutting (including cutting with a gate cutter and nipper) on molded products molded with high-strength resin such as acrylic resin, so that cracks are prevented from occurring on molded products. Can be.

Further, the present invention according to claim 13 provides:
At any time before or after the sixth step, a release sheet made of an adhesive layer and release paper is bonded to the back surface of the resin via the adhesive layer, and the resin is cut in the seventh step while leaving the release paper. Thereby, a plurality of molded articles are aligned on the surface of the release paper, and the counting at the time of delivery and the handling in the assembly process are further facilitated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view conceptually showing a configuration of an injection molding machine according to a first embodiment of the present invention.

FIG. 2 is a front view of a female mold according to the first embodiment.

3 (a) to 3 (d) are AA to D- in FIG. 2, respectively.
It is arrow sectional drawing to D.

FIG. 4 is a front view of a male mold according to the first embodiment.

5 (a) to (d) are AA to D- in FIG. 4, respectively.
It is arrow sectional drawing to D.

FIGS. 6A to 6D are FIGS. 3A to 3D, respectively.
FIG. 6 is a cross-sectional view illustrating a state in which corresponding parts in FIGS. 5A to 5D are superimposed.

FIG. 7 is a longitudinal sectional view corresponding to FIG. 6D, showing a state in which a resin is injected into a molding space portion and an auxiliary space portion.

FIG. 8 is a longitudinal sectional view showing a state where a male mold is released from a female mold.

FIG. 9 is a longitudinal sectional view showing a state where the in-process resin after solidification is released from the female mold.

FIG. 10 is a rear view of the resin in progress according to the first embodiment.

11 (a) to (d) are AA to FIG. 10 respectively.
It is arrow sectional drawing to DD.

FIG. 12 is a plan view of a base according to the first embodiment.

FIG. 13 is a sectional view taken along the line AA of FIG.

FIG. 14 is a cross-sectional view of a state where a resin in progress is placed on the base of FIG.

FIG. 15 is a front view before assembling a casing as a molded product in the first embodiment.

FIG. 16 is a front view of a female mold according to the second embodiment.

17 (a) to (d) are AA to FIG. 16 respectively.
It is sectional drawing of the state which superimposed the female mold | die as an arrow sectional view to DD, and the part corresponding to a female mold among male molds.

18 is a longitudinal sectional view corresponding to FIG. 17 (c), showing a state in which a resin is injected into a molding space portion and an auxiliary space portion.

FIG. 19 is a longitudinal sectional view showing a state where the male mold is released from the female mold.

FIG. 20 is a longitudinal sectional view showing a state in which the in-process resin after solidification is released from the female mold.

FIG. 21 is a rear view of the resin in progress according to the second embodiment.

22 (a) to (d) are AA to FIG. 21 respectively.
It is arrow sectional drawing to DD.

FIG. 23 is a plan view of a base according to the second embodiment.

24 (a) and (b) are a sectional view taken along the line AA and a sectional view taken along the line BB of FIG. 23, respectively.

FIG. 25 is a rear view of the in-process resin after screen printing.

26 is a sectional view taken along the line AA of FIG. 25.

FIG. 27 is a longitudinal sectional view conceptually showing cutting by laser.

FIG. 28 is a front view of a name plate.

FIG. 29 is a longitudinal sectional view of a resin in progress with a release sheet attached thereto in the third embodiment.

FIG. 30 is a front view of the in-process resin after press cutting.

31 (a) and (b) are a cross-sectional view taken along the line AA and a cross-sectional view taken along the line BB of FIG. 30, respectively.

[Explanation of symbols]

 1, 40 Female mold 2, 50 Male mold 3, 60 Molding space 4 Resin 5 Hopper 6 Cylinder 7 Resin pellet 8 Screw 9 Ejector 9a Protruding pin 10 Housing 11, 21 Reference plane 12, 13 Recess 14, 45 Injection Holes 15, 16 Auxiliary recess 17 Regulatory projection 18, 46 Acceleration recess 19 Air vent 22, 23, 25 Convex 24 Groove 31, 61 Auxiliary space 32, 41 In-process resin 33, 48 Auxiliary resin 34, 62 Flow promoting part 35 Flow Control part 36 Positioning part 42 Name plate 70, 80 Base 90 Laser 100 Release sheet

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/26-45/44

Claims (13)

(57) [Claims] 1. An injection molding method in which a molten resin is injected into a space between a male mold and a female mold disposed opposite to each other through an injection hole, and the resin is solidified to form a molded product. A method for producing a resin molded product, wherein the plurality of space portions are connected to a plurality of molding space portions adapted to the outer shape of the molded product, and the plurality of molding space portions and the injection hole. A second step of injecting the molten resin into the auxiliary space through the injection hole; and a second step of injecting the molten resin into the auxiliary space through the injection hole. A third step of injecting each of the molding space portions through the auxiliary space portion. 2. In the first step, the auxiliary space portion is disposed between the plurality of molding space portions arranged in parallel with each other, and the auxiliary space portion is disposed in the auxiliary space portion. The method for producing a resin molded product by injection molding according to claim 1, wherein the resin molded product is formed around the entire circumference. 3. The method according to claim 1, wherein, in the first step, a flow promoting section is provided in the auxiliary space to increase the thickness of the auxiliary space to promote the flow of the resin in the auxiliary space. The method for producing a resin molded product by injection molding according to claim 1 or 2. 4. The method according to claim 1, wherein, in the first step, a flow restricting portion is provided in the auxiliary space portion to reduce a thickness of the auxiliary space portion to restrict a flow of the resin in the auxiliary space portion. The method for producing a resin molded product by injection molding according to claim 1. 5. The method according to claim 1, wherein in the first step, a positioning portion is provided in the auxiliary space portion, the positioning portion forming a positioning hole for regulating the positions of the auxiliary space portion and the molding space portion. Item 5. A method for producing a resin molded product by injection molding according to any one of Items 1 to 4. 6. The first step is characterized in that an air vent for discharging gas in the molding space and the auxiliary space to the outside of the space is formed in communication with the auxiliary space. A method for producing a resin molded product by injection molding according to claim 1. 7. The method according to claim 1, wherein in the first step, a contact surface between the male mold and the female mold is located only on a side of the auxiliary space. Production method of resin molded products by injection molding. 8. The method according to claim 3, further comprising: after the third step, a fourth step of inserting a projecting pin into the auxiliary space and releasing the solidified resin in the molding space and the auxiliary space. The method for producing a resin molded product by injection molding according to any one of claims 1 to 7. 9. After the fourth step, the resin discharged to the outside of the molding space portion and the auxiliary space portion is arranged on a base, and a guide projection provided on the base is attached to the positioning portion. A fifth step of fixing the relative position between the resin and the base by inserting the resin into the positioning hole formed in the step. 9. The resin molding by injection molding according to claim 8, wherein the vertical position of the resin injected into the molding space and solidified by the vertical movement of the block portion on the base is adjustable. Product production method. 10. The method according to claim 6, wherein the resin is formed in multiple faces, and after the fifth step, a predetermined surface treatment and / or rear face treatment is applied to the resin arranged on the base in a multifaceted manner. And / or a seventh step of cutting the resin placed on the base into a predetermined dimension in multiple directions. The method of producing a resin molded product by injection molding according to claim 9, further comprising: . 11. In the seventh step, the resin is injected into the molding space and solidified, and
The method for producing a resin molded product by injection molding according to claim 10, wherein the resin is separated into an auxiliary resin injected into the auxiliary space and solidified. 12. The method for producing a resin molded product by injection molding according to claim 10, wherein in the seventh step, the multi-plane cutting is performed by a laser. 13. Before or after the sixth step, a release sheet comprising an adhesive layer and a release paper is adhered to the back surface of the resin via the adhesive layer, and in the seventh step, the release paper The method for producing a resin molded product by injection molding according to claim 10, wherein the resin is cut while leaving the resin.