JPS60228119A - Manufacture of container made of thermoplastic resin - Google Patents

Abstract

PURPOSE:To reduce the fraction deflective rate by taking out a molded article through a wire rope method after vacuum injection molding of a developing plate made of thermoplastic resin for canning has been performed in the inside of a mold. CONSTITUTION:At the time of injection molding of a developing plate 2 for canning having a ruled line part 12 and notched parts 13-16, after mold breaking has been completed by injecting molten resin into a cavity 29 through gates 28a, 28b and solidifying the same through cooling, an outlet 35 of a gas vent hole 35 is switched over to a pressing gas supply system from a vacuum system, compressed air is blown through a gas vent slit 31 and a molded article is ejected through a gas blow.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to a unit of a certain volume such as a tape cassette for a video tape recorder, a floppy disk, a video disk, a digital audio disk, and a sheet of photosensitive material. The present invention relates to a method for manufacturing a thermoplastic resin container suitable for accommodating products such as film, photographic paper, and IC printed boards.

[Prior art]

Thermoplastic resin containers with small volumes such as those mentioned above can be three-dimensionally molded by direct injection molding, but cases that store items larger than a certain volume, such as tape cassettes for video tape recorders, can be molded using direct injection molding. in case of,
Since it is impossible to perform three-dimensional molding by direct injection molding, a method is used in which boxes are manufactured from expandable plates.

Conventionally, the development plate for such synthetic resin containers is made by extruding a long synthetic resin plate from a T-die, printing it if necessary, and then cutting it into a plate of a certain size. The parts corresponding to the creases (hereinafter referred to as ``key line parts'') were compressed or cut, the cut parts were punched out, and in some cases, the surface was stamped with foil or embossed. .

However, such conventional manufacturing methods require a large number of man-hours and are inefficient, lack uniformity in the strength of the silicon wire, surface shape, thickness of the developed plate, etc., and have a high incidence of defective products in terms of quality. In addition, because the wires, shaping, and cutting are done forcibly, wire cracks may occur, the surface of the wire grooves may become rough, and the appearance is poor due to debris adhering to the cut surface, resulting in excessive cutting allowances. Since Kirikuyo was disposed of, there were inconveniences in terms of cost and industrial waste generation. Furthermore, in terms of quality, notches and other punched edges are crushed and cut scraps are generated, which fall off during use, and when storing video cassettes, for example, these adhere to the tape and drop. out(
It was also impossible to change the thickness of parts for differentiation, or to process special shapes or fine letters or shapes.

In order to eliminate the above-mentioned drawbacks of the prior art, one of the inventors of the present invention previously proposed the production of a deployable plate for such a synthetic resin container by injection molding (Japanese Patent Application No. 1983).
-26007). In other words, it has been considered difficult to injection mold a deployable plate with a wide area beyond a certain level using resin, and no attempt has been made to do so, but it is now possible to make a deployable plate with a diagonal line or notch by injection molding. It has also been found that by doing so, the drawbacks of the prior art as described above can be completely eliminated.

The spread plate formed by the above method has an average thickness of 0.3 to 3 mm and an area of, for example, 30 cm x 30 cm or more, so that the molten resin is uniformly and quickly transferred from the gate to the molding cavity during pouring. If the resin is not filled, parts with different densities of resin will occur, causing deformation after molding. Especially when printing on a developing plate and heating it to quickly dry it, the deformation will be severe, as well as flow marks, sink marks, etc. Failures such as silver threads, weld lines, bubbles, and burns may occur. Therefore, in order to prevent such failures, the position of the gate, the composition of the resin, the type of additives, etc. must be appropriately selected.

The same inventor first discovered that it is necessary to further improve the above method (as a result of consideration, by manufacturing the developing plate by vacuum injection molding in the entire mold, it is possible to create a developing plate with a precise shape that does not cause the above-mentioned failures). (Patent application filed on January 23, 1980).

The inventors of the present invention have found that the method for molding a spread plate using the all-in-mold vacuum injection molding method as described above has the following problems.

That is, after a developing plate is molded in a mold, the mold is opened while being held on the movable mold side, and an ejector pin provided on the movable mold is protruded to eject the developing plate. In this case, marks from the ejector pin will appear on the molded product, which not only impairs the appearance of the molded product, but also prevents the ejector from ejecting in a uniform state in the case of flat, relatively large-area plate-like products such as expansion plates. ejector pins must be provided in several locations, and care must be taken to ensure that the ejector pins are placed in locations where the puncture marks are not very noticeable. In addition, an ejector plate is required to move the ejector pin, and when the developing plate has a large area or when molding multiple developing plates at the same time, an ejector plate with a large area is required, and the injection molding equipment becomes large. There is a problem with becoming.

Furthermore, when injection molding is performed using split molds, after molding,
It is necessary to open the mold while holding the molded product on the movable mold side. In general, for molded products that are concave, if the movable mold is made convex, the molded product can be held in the movable mold and opened by the contraction of the molded product itself, so is there no problem?
In the case of flat molded products such as expansion plates, there is a problem in that it is difficult to always hold the molded product on the side of the movable mold because the shrinkage effect described above cannot be utilized.

The present inventors conducted further studies to solve the above-mentioned problems, and as a result, they were able to solve these problems by adopting an air blower type and a gas vent slit, thereby achieving the present invention.

[Purpose of the invention]

Therefore, an object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to use a thermoplastic resin that can produce a developing plate without forming ejector pin puncture marks by full-mold vacuum injection molding. An object of the present invention is to provide a method for manufacturing containers.

Another object of the present invention is to provide a thermoplastic resin container that can securely hold the molded expansion plate in a movable mold and open the mold when the expansion plate is manufactured by in-mold vacuum injection molding. The purpose of this invention is to provide a method for manufacturing the same.

Another object of the present invention is to produce, by injection molding, a developing plate for a thermoplastic resin container that has a uniform density and a precise shape, regardless of the position and number of gates, the composition of the resin, etc. An object of the present invention is to provide a method for manufacturing a thermoplastic resin container.

A further object of the present invention is to provide a method for manufacturing a thermoplastic resin container that greatly reduces failures such as flow marks, sink marks, silver threads, weld lands, bubbles, and burns, and has high ain'd impact strength.

The above objects of the invention are achieved by the invention described below.

[Structure of the invention]

That is, the first aspect of the present invention is to use a full-mold vacuum injection molding method (the inside of the mold is sealed from the outside air, and the air and gas inside the mold are Before injecting and filling the thermoplastic resin from the resin injection port (gate), the inside of the mold is cleaned several times in order to remove
A method for producing a thermoplastic container, which comprises producing a thermoplastic container by an injection molding method in which the container is formed in a vacuum state of less than This is a method for manufacturing a thermoplastic resin container.

Another aspect of the present invention is a thermoplastic resin container which is mainly made of thermoplastic resin, and which comprises producing a developing plate having a diagonal line part and a cutout part by an in-mold vacuum injection molding method, and then manufacturing this into a box. In the manufacturing method, the mold is composed of a fixed mold and a movable mold, a gas vent slit is provided in the mold in which a cavity for molding the expansion plate is formed, and after molding, the expansion plate is exposed to negative pressure from the gas vent. This method of manufacturing a thermoplastic resin container is characterized in that the mold is opened while the developing plate is held on the mold side by keeping the mold at a constant temperature, and then the molded product is ejected by blowing air from the gas vent slit. .

Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings.

In the present invention, a thermoplastic resin container 1 in the shape of a rectangular y-cuboid with an open opening on the negative side as shown in FIG. 1 is manufactured by box-forming the expandable plate 2 shown in FIG.

In FIG. 2, the development plate 2 includes a front part 4, a back part 5, a left side part 6, a right side part 7, a bottom part 8, and a left side overlapping part 9.
, the right side overlapping part 10, the flaps 11, 11α, and the wire part 12, and by making these into a box, the first
A thermoplastic resin container 1 as shown in the figure is formed. 1st
In the figure, the correspondence of each part of the unfolding plate in FIG.

Conventionally, in cases where a container 1 made of thermoplastic resin as shown in FIG. After printing and drying, cut the material, cut out the notches marked with diagonal lines in Figure 2, shape them, punch out the cutouts with the lines attached, or cut the notches into uncut rectangles. After forming the plate, the highlighted portion 12 is formed by compression shading or cutting, and then the hatched cutout portion 13° 14.1 is formed.
5.16 was punched and, in some cases, the front part 4 etc. was stamped to create a development plate, which was then manufactured into a box.

According to the present invention, the developing plate 2 as shown in FIG. The thermoplastic resin container 1 as shown in FIG. 1 is produced by vacuum injection molding, and is subjected to printing or the like if necessary, and then box-made.

In the method of the present invention, various thermoplastic resins can be used as the thermoplastic resin used in vacuum injection molding, but in particular, polyolefin thermoplastic resins (including copolymers with other thermoplastic resins) or polystyrene thermoplastic resins are used. Plastic resin or ABS thermoplastic resin A mixed resin of two or more of these thermoplastic resins is used, and various polypropylene resins, especially various nucleating agents, are used in an amount of 0.01 to 2'1! Propylene/ethylene random copolymer resin containing L parts has low cost, printability,
Manufacturing accuracy, dimensional stability, wire strength, surface strength, rigidity,
Suitable for injection molding. These thermoplastic resins contain various blowing agents, white pigments (titanium oxide, talc, mica, calcium carbonate, clay, etc.), various carbon plaques, various coloring pigments, and various golden bird powders (aluminum powder, tin powder, etc.). , aluminum yeast, etc.), various organic or inorganic fiber substances such as various metal fibers, glass fibers, and carbon fibers, various other coloring dyes, various antistatic agents, various silicones, surfactants, and stearic acid. Various additives such as lubricants such as sodium and antioxidants can be added.

Furthermore, when in-mold injection molding is performed in the method of the present invention, the injection port (gate) for the molten thermoplastic resin is not limited to one location, but can be provided at a plurality of locations. By doing so, the flow of the thermoplastic resin improves during injection molding, and it is possible to prevent the occurrence of a boundary line where the flow of the thermoplastic resin joins, which is called a weld line. These injection ports (gates) are shown in Fig. 2 on the inside of the container to improve the fluidity of the thermoplastic resin in terms of the appearance of the container and in the structure where the diagonal line is provided only on the surface of the container as shown in Fig. 3. taX, X2. X
, Yl, and Y3, preferably in the vicinity of horizontally or vertically symmetrical positions, where the thermoplastic resin can flow in approximately equal time to all four corners. It is particularly desirable to provide the injection port (gate) for the thermoplastic resin at only one location, x2Y2 in FIG. Moreover, if it is provided in two places, it is provided at the positions Yl and Y3 in FIG.

As another example of providing two locations, it is also desirable to provide locations X1 and X3 in FIG. Although there are various known shapes of the resin injection port (gate), which will be described later, a pin gate is preferred from the viewpoint of leaving no marks on the appearance. Another desirable location for the resin injection port (gate) is when a side gate or the like is used, the end of the product at the notch 13°, 14, 15, 16 of the development plate shown in Fig. Other desirable positions include a position where the resin injection port does not appear on the surface after forming the box;
As an example, the overlapped portion 9 of the left and right sides of the expansion plate shown in FIG.
, 10 or the front and rear ends of the flaps 11 and 114, preferably in the vicinity of the left and right or vertically symmetrical positions as described above.

In any case, in the present invention, the number and position of resin injection ports (gates) are determined depending on the shape of the developing plate, the fluidity (melt index) of the thermoplastic resin, the ease of generating gate marks, the ease of generating weld lines, etc. The present invention is not limited to the above description because the resin injection ports (gates) can be placed in any position on the expansion plate, in any number or shape, and are suitable for injection molding and can be applied to the container when molded into a box. It is desirable to prevent it from appearing on the surface (visible surface), both from the viewpoint of appearance and the fluidity of the resin.

FIG. 4 is a schematic cross-sectional view showing one example of an apparatus used for full-mold vacuum injection molding used in the present invention. Note that in this example, 1
Although a mold having several cavities for molding a spread plate is illustrated, the present invention is not limited to this. Double horizontal molds are formed on both sides so that molten resin can be supplied to both cavities from one injection tube at the same time, and the number of cavities has been further increased to supply molten resin from one or two injection tubes. A multilayer mold that can be used can be used. In either case, the exhaust means described below can be used.

In the injection molding apparatus illustrated in FIG. 4, the identification side is attached to the plate 21.
The fixed mold includes a fixed mold plate 22, and the movable mold includes a plate 23, a movable mold plate 24, and a core 25.

For mounting on the fixed side of the fixed mold, a bush 26 is provided on the plate 21 to supply molten resin from an injection tube (not shown).
The stationary template 22 is provided with runners 27 (27d, 27h) and gates 28α, 28h for guiding the molten resin into the cavity 29 for molding the expansion plate.

An appropriate number of core inserts 3012.30A, 30C are arranged on the side of the core 25 of the movable mold facing the fixed mold, and a cavity 29 for molding the expansion plate is formed between the core 25 and the mold plate 22. . The core population is the key line 1 of the expansion plate shown in Figure 2.
The gas vent slits 31 are formed in the contact surface of each core insert (fourth gas vent slit 31).
The gas vent slit (31 shown in the figure) extends perpendicularly to the plane of the paper with a gap of approximately Q, 01 mg). The gas vent slit 31 opens at the base of the wire-forming projection 32, as shown in a partially enlarged sectional view in FIG.

The movable side mold &24 has gas vent holes 33 that communicate with the gas vent slits 31, and gas vents and holes 34 that connect each gas vent hole 33 to a vacuum device (for example, a vacuum pump).
is provided, and the outlet 35 of the gas vent hole 34 is connected to a suitable vacuum device or pressurized gas supply device according to the injection control pattern of the present invention.

Note that 35 is a backing (O-ring) made of an elastic body such as rubber, and is provided to cut off the vacuum system inside the mold from the outside air.

In addition, passages for heat medium and cooling medium are provided in the mold.
When supplying molten resin (during injection), the mold is kept at an appropriate temperature, and during molding, the mold is cooled.

When carrying out the present invention using an in-mold vacuum injection molding apparatus as exemplified in FIG. 4, it can be carried out by, for example, producing a developing plate according to the following injection control cycle and manufacturing the plate into a box. .

Injection control cycle (1) Close the fixed mold and movable mold and start mold clamping. (
In this case, the injection tube is attached to the bushing 26 of the fixed mold.) (2) Connect the gas vent outlet 35 to a vacuum device and start evacuation of the cavity.

(3) When the mold clamping is completed, the cavity is completely evacuated, injection is performed, and the molten resin is guided from the injection tube through the runner 27 to the cavity 29.

(4) Start cooling part of the cavity and complete molding.

(5) Start opening the mold with the gas vent hole outlet connected to the vacuum device (move the movable mold. In this case, the molded product is receiving negative pressure from the gas vent slit, so the molded product is held in the movable mold. (6) When the mold opening is completed, switch the gas vent hole outlet 35 from the vacuum device to the pressurized gas supply device, switch the air to the gas supply device, blow air from the gas vent slit, and blow the molded product with the gas blower. eject.

(7) Next, start mold clamping, switch the gas vent hole outlet 35 from the pressurizing device to the vacuum device, and repeat the above operation.

Since the present invention produces the development plate as described above,
A homogeneous and precise molded product can be obtained in an extremely short time, and since the molded product is ejected using air spray, there are no ejector pin puncture marks and a good-looking developing plate can be obtained. . Furthermore, since the molded product is kept under negative pressure by the air vent slit, a flat molded product such as a developed mold can be reliably held on the movable mold i side when the mold is opened. In the present invention, a container made of thermoplastic resin is obtained by molding the expandable plate produced as described above, that is, a container made of thermoplastic resin is obtained by molding the expandable plate produced as described above.
Various printing methods (silk screen printing, on-set printing, flexographic printing, gravure printing, pad printing, electrostatic transfer printing, hot stamping foil stamping),
(transfer printing, inkjet printing, rotary roll printing, etc.) to create a printing layer of one or more colors of each type (if necessary, a primer coating or a protective layer to protect the printed surface may be applied to improve printability). After that, it is possible to fix the printing layer to the developing plate by using cold air, hot air, various types of air, infrared irradiation, ultraviolet irradiation, electron irradiation, etc.Assembling a continuous printing line after vacuum injection molding in the entire mold reduces the production cost, This is effective in reducing inventory and printing man-hours.

When manufacturing a thermoplastic resin container 1 as shown in FIG. 1 by the method of the present invention, it is preferable that the development &2 shown in FIG. 2 has a cross-sectional shape as shown in FIG. 3. The plate thickness t is generally from about 0.3IN to about 3N, and the silicon wire portion is preferably 5% or more of the average plate thickness tK of the developed plate.
% or more, most preferably 30 inches or more (by doing so, even if the printing ink is rapidly fixed to the development plate by drying or chemical reaction after printing, it will not warp or twist.) In the present invention, the plate thickness is limited to 0.3 to 3 mm in order to ensure cooling efficiency, prevention of warping, sink marks, and kinks, and strength of the expansion plate 2, which is an injection molded product. In order to prevent warpage and sink marks when the printing ink is fixed and to ensure the fluidity of the thermoplastic resin and at the same time to facilitate box manufacturing, the wire portion should be 5% or more, preferably 15% or more, and most preferably 3% or more of the plate thickness t. (It is necessary to reduce the thickness by 1 or more, and from the viewpoint of strength, it is necessary to ensure a thickness of at least 0111 or more.

In addition, although the cross-sectional shape of FIG. 3 shows the case where the C line is formed only on one side of the expansion plate, the C line may be provided at symmetrical positions on both sides depending on the case.

Before manufacturing the box, the entire front and back surfaces or the outer or inner surfaces of the front part 4, back part 5, left side part 6, right side part 7, bottom part 8, etc. are embossed, (textured) grooved, or uneven. It is also selectively applied to improve the appearance and ease of handling. In conventional manufacturing methods, these were performed by embossing, but in the method of the present invention, these surface treatments can also be performed during in-mold vacuum injection molding.

〔Example〕

Next, in order to further clarify the effects of the present invention, examples are listed below.

(1) A two-stage, four-cavity mold for molding in a developed sheet metal mold as shown in FIG. 6 was used.

Figure 6 is a schematic diagram showing the open state of the mold, and
4 pieces can be molded at the same time. The mold consists of a fixed mold 41 and a movable mold including an intermediate plate 42 and a movable core 43.

The fixed mold 41 includes a sprue bush insertion opening 44 for the intermediate plate, and two cavities 45 (Z
, 45A, gas vent holes 46 and gas vent slits 47 for vacuum and air blow explained in FIG.
is provided. These operating mechanisms are as described with respect to FIG. 4, and are coupled by a gas vent outlet 48 to an external vacuum system or pressurized gas supply system according to the injection control pattern described above.

The intermediate plate 42 is provided with a spool bush 49 provided with a spool for molten resin, a manifold 950 for bath molten resin, and a gate 51.

The movable plate 43 is provided with a development plate molding cavity 45, a gas vent hole 46, a gas vent 46, and a gas vent slit 47, similar to the fixed mold 41 (simultaneously). It acts on

During use, the fixed mold and the movable mold are closed, the injection tube 52 is set, and the injection control process is repeated through a series of vacuum operation → injection → molding → mold opening → gas blow (molded product eject) → opening/closing and vacuum operation. Four developing plates are molded at the same time.

In addition, in this device, after the first injection molding is completed, molten resin exists in the Mayu field 50 and is maintained in a molten state, and the next vacuum operation will cause it to pass through the gate 51 and enter the cavity. At the same time as being supplied to the tee 47, new molten resin is supplied from the injection cylinder 52. In this case, the diameter of the gate 51 is very small, and the molten resin can pass through when an exhaust force is applied from the outside, but when there is no exhaust force, there is almost no leakage of the molten resin. moreover,(
The same applies to Fig. 4) Gas vent frit 4
The gap 5 is extremely small and allows air to pass through, but not the molten resin supplied to the cavity 47 by vacuum operation.

Also, in this case, when the mold is opened, the gas vent cavity is connected to the vacuum system, creating negative pressure on the back side of the molded product and holding it on the fixed mold 41 and movable core 43 side. .

In this case, the mold was designed so that the dimensions of the expansion plate were as follows. The thermoplastic resin injection port (gate) is located at 1 of Y1 and Y3 on the inside of the development plate (inner bottom surface in contact with the product) in Figure 3.
There were several locations.

Vertical and horizontal dimensions of the expansion plate: The longest part is 247cm x 23714mm Thickness of the expansion plate: 0.9m Dimensions of the lined part: Width 1.5mtn, depth 0.25ig Cross-sectional shape of the lined part: Figure 3 Incision shown in 13.1
Dimensions of 4: Length approx. 70xxs Width 20n Dimensions of notch 15.16: Polygon whose longest part is 37 mm x 281 RN (2) Using this mold, melt molten thermoplastic resin with the following composition and vacuum inside the mold. Injection molded: Mitsui Petrochemical e# polypropylene nail grease, (MI-4
01I/10 minutes)・・・・・・96.8 Heavy steel plate Shinetsu silicone ■Back dimethyl polysiloxa/, KF-96 (intermediate product name)・・・・・・0.1 weight - titanium oxide・...2 weight - Antistatic agent Electroslipper manufactured by Kao Soap Co., Ltd. ...0.1 weight i% (3) Assemble each injection molded development plate and apply ultrasonic waves to the overlapping parts. Welded with a joining machine and the approximate dimensions are 192 mm x 105 mm x 2811 mm
Cases for video tape cassettes were produced.

When the number of boxes manufactured is 300,000, the manufacturing cost is reduced to 60% compared to the conventional manufacturing method that includes cutting and punching processes, and the incidence of defective products is reduced to 11 boxes compared to the conventional method. In the method of the present invention, the number was 1.

In addition, according to the method of the present invention, the molded product has no ejector marks at all and has a good appearance, and throughout the entire process, when the mold is opened, the molded product is reliably formed into a core with a cavity or a metal mold. held on the mold side. Furthermore, according to the present invention, since the entire in-mold vacuum injection molding method is used, the number of man-hours is reduced, manufacturing costs are reduced, the process is stabilized, and the appearance and
Significant effects can be obtained, such as improving quality such as accuracy and surface finish, automating work, and reducing industrial waste.

The present invention is not limited to the embodiments, and can be applied to a wide range of applications, for example as shown below.

The present invention is not limited to the embodiments, and can be widely applied, for example, as shown below.

(1) The shape of the expansion plate is not bilaterally symmetrical; for example, the shape of the front part and the shape of the back part may be different.

(2) Even if the thickness of the side part is the same as the remaining thickness of the silicon wire part, the strength can be maintained by overlapping and joining.

(3) The shape of the notch is rectangular, square, trapezoidal, semicircular,
It can have various shapes such as semi-ellipse, equilateral triangle, isosceles triangle, and arrow shape.

(4) The remaining thickness of the wire part may be partially thickened to improve the flow of resin during vacuum injection molding within the entire mold.

(5) The surface of the mold is processed to have a transparent window in one or more places on the development plate, and the product name, company name, picture, etc. are printed on the inside and outside surfaces of the case, and the surface of the mold is treated with grain, grain, rope, and vertical stripes. , horizontal stripes, lattice,
It can be made to have a pattern (texturing) such as a fine-grain surface texture. As a specific grained sample, 21014 or more of "Bearon Shibo" published by Tokyo Pearlon Co., Ltd. is presented.

(During 6-inch injection molding, the thermoplastic resin is a copolymer,
It can be a mixed resin of more than one type of thermoplastic resin.

(7) For thermoplastic resins, color pigments or color dyes are added to IPJ.
Or many kinds can be added.

(8) After the development plate is fully in-mold injection molded, a printing process or pasting process can be selectively added after Mff in the box manufacturing process to add marks and letters.

[Brief explanation of the drawing]

Fig. 1 is an external view showing an example of a thermoplastic resin container manufactured according to the present invention, Fig. 2 is a plan view of a developing plate, Fig. 3 is a sectional view of the A-B plane of the developing plate in Fig. 2; FIG. 4 is a schematic cross-sectional view showing an example of an all-in-mold vacuum injection molding apparatus used in the present invention, and FIG. 5 is a schematic cross-sectional view showing an example of a multi-stage in-mold vacuum injection molding apparatus 12, 13, and 13 used in an embodiment of the present invention. 14.15.16
...Notch X1. X2. X3. Yl, Y3...Gate 21...Fixed side mounting plate 22...Fixed side template 23
...Movable side mounting plate 24...Movable side template plate 25-...-
Core 27C27ct, 27b) - Hot water conductor 28α, 28
h...Gate 29...Cavity 31 for molding the expansion plate...Gas vent slit 32...Protrusion part 33, 34 for forming the wire 34...Gas vent hole 41...Fixed mold 42
... Intermediate core 43 ... Movable core 45 ... Cavity for molding the development plate 46 ... Gas vent hole 47 ... Gas vent slit 50 ... Manifold for molten resin 51 ... Gate (3 others) ) Figure 3 Figure 4 Figure 6 Hand, continuation of amendment May 2, 1985 To the Commissioner of the Patent Office (To the Examiner of the Patent Office) 1. Indication of the case Patent Application No. 75813 of 1981 2. Invention Name of Process for Manufacturing Thermoplastic Resin Containers 3, Person Making Amendment Relationship to Case: Name of Patent Applicant (520) Fuji Photo Film Co., Ltd. (and 1 other person)
Kasumigaseki Building Post Office Box @ No. 49 Eikou Patent Office Telephone (581)-9601 (Representative) Name Patent Attorney (8107) Kiyotaka Sasaki (and 3 others) 6. Number of inventions increased by amendment 0 Page line of specification Before correction After correction 57 Silver thread Silver thread 85 Thread 85 Weld land Weld line 116 Vacuum injection molding Vacuum injection molding in all molds 127 Injection molding in all molds Vacuum injection molding in all molds 12 From the bottom 4X2X2Y2 136 Gate entrance Gate 15 From the bottom 1 Paper core surface 16 2 molding devices from below 214 All in-mold molding All in-mold vacuum injection molding 21 1 from below Manifold Manifold 221 Filter manifold manifold 232 Frit 45 Slit 47 2344745 2611 Fig. 6 Fig. 2 23121 2 locations 24696.8% by weight 97.8% by weight 262 Before and after correction of page lines of Myojin Flow - ■ - - ■ - - - - - - - - - - - - - - - - - - ■−
12711X2X2Y2 or more

Claims (3)

[Claims] (1) A method for manufacturing a thermo-0T plastic resin split container, which comprises producing a spread plate made mainly of thermoplastic resin and having a wired portion and a cutout portion by an in-mold vacuum injection molding method, and forming the same into a box. A method for manufacturing a thermoplastic resin container, which comprises removing an injection-molded expansion plate from a mold using an air processor. (2) A method for manufacturing a thermoplastic resin container, which comprises producing a developing plate made mainly of thermoplastic resin and having a diagonal line part and a cutout part by an in-mold vacuum injection molding method, and forming the same into a box. The mold is composed of a fixed mold and a movable mold, a gas vent slit is provided in the mold in which a cavity for molding the expansion plate is formed, and the expansion plate is maintained under negative pressure from the gas vent slit after molding. 1. A method for producing a thermoplastic resin container, which comprises opening the mold while holding it on the mold side, and then ejecting the molded product by blowing air through the gas vent slit. (3) The average thickness of the developing plate is 0.3 to 3 ml, the average thickness of the diagonal line part is 5% or more thinner than the average thickness of the developing plate, and the average thickness of the diagonal line part is 0.15 to 1. 5. A method for manufacturing a thermoplastic resin container according to claim 1 or 2.