JP2011178119A - Resin molding and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin molding which is easy of production and high in designability and a method for producing the resin molding. <P>SOLUTION: In the method for producing the resin molding including a process for charging a resin material from the hopper 11 of an injection apparatus 10, a process for melting the resin material by heating with a heater 13 in a screw cylinder 12, a process for extruding the molten resin material from a nozzle 14 at the tip of the screw cylinder 12 toward a mold 21, a process for injecting the molten resin material into the cavity of the mold 21 through the gate 23 of the mold 21 which is positioned to contact the nozzle 14, and a process for solidifying the resin material in the mold 21, the resin material charged in the hopper 11 is composed of a glass piece-containing material and thermoplastic resin pellets. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a resin molded product and a method for producing the same. More specifically, the present invention relates to a resin molded product to which glass fiber is added and a method for producing the same.

  In an electric product such as a cellular phone, the thermoplastic resin used in the casing is required to be as thin as possible to reduce the size and weight. Also, since it is used for the exterior part, beauty is required.

  For example, Patent Document 1 describes a technique of injection molding using a polypropylene resin composition containing a glass flake pigment as a raw material to form a resin molded product that exhibits a completely new design effect.

  Patent Document 2 describes a glittering resin molded product that can be integrally formed by vacuum molding or injection molding and has excellent metallic luster and impact resistance. The technique is a method having a glittering layer composed of a resin composition containing a glittering glass flake coated with metal and a thermoplastic resin.

  Patent Document 3 describes a molded article of a thermoplastic resin capable of forming a sense of depth and a three-dimensional pattern (silk tone) on the surface appearance. The technique is a method of blending glass fiber, glass flake, pearl pigment, metallic pigment, or metal-coated glass flake into a thermoplastic resin.

JP 2001-158858 A Japanese Patent Laid-Open No. 2004-50786 International Publication No. 2002/62900

  In the related technology, the entire molded product has a uniform pattern. The material mixed with the thermoplastic resin, such as glass flakes or pearl powder, can be given gloss, lamé, or a pattern, but the entire surface will be the same pattern, It was difficult to characterize with.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a resin molded product that is easy to manufacture and has high designability, and a manufacturing method thereof.

The method for producing a resin molded product according to the first aspect of the present invention includes:
A step of feeding a resin material comprising a glass piece-containing material and a thermoplastic resin pellet from a hopper in an injection device;
Heating and melting the resin material with a heater in a screw cylinder;
A step of extruding the molten resin material from the nozzle at the tip of the screw cylinder toward the mold;
Injecting the molten resin material into the cavity of the mold through the gate of the mold located in contact with the nozzle;
Solidifying the resin material in the mold;
It is characterized by providing.

The resin molded product according to the second aspect of the present invention is:
It manufactures with the manufacturing method of the resin molded product concerning a 1st viewpoint.

  According to the present invention, a resin molded product that is easy to manufacture and has high designability can be formed.

It is a composition schematic diagram showing an example of an injection molding machine used for fabrication of a resin molded product concerning an embodiment of the invention. It is a composition schematic diagram showing an example of a metallic mold. It is a top view which shows the pattern of a resin molded product. It is a top view which shows the pattern of a resin molded product. It is a top view which shows the pattern of a resin molded product. It is the structure schematic which shows an example of the injection molding machine used for shaping | molding of the resin molded product which concerns on the modification of embodiment of this invention. It is a top view which shows the pattern of a resin molded product. It is a top view which shows the pattern of a resin molded product. It is a top view which shows the pattern of a resin molded product.

(Embodiment)
FIG. 1 is a schematic configuration diagram showing an example of an injection molding machine used for molding a resin molded product according to an embodiment of the present invention.

  The injection molding machine 100 includes an injection device 10, a mold part 20, and a mold clamping device 30.

  The injection device 10 includes a hopper 11, a screw cylinder 12, a heater 13, and a nozzle 14. The hopper 11 is a place where a resin material is put. The screw cylinder 12 is rotated by using a hydraulic motor (not shown) or the like, and mainly performs plasticizing operations including resin transfer, compression, kneading, melting, and metering operations. The heater 13 heats in order to plasticize the material. The heater 13 is disposed so as to surround the periphery of the screw cylinder 12. The nozzle 14 is attached to the tip of the screw cylinder 12 and is in close contact with the mold part 20 to inject resin into the mold.

  FIG. 2 is a schematic configuration diagram illustrating an example of a mold. The mold unit 20 includes a mold 21, a cavity 22, a gate 23, an ejector 24, a fixed plate 25, and a movable plate 26. The cavity 22 is a cavity of the mold 21 and resin is injected. The gate 23 is in close contact with the nozzle 14 and is an injection port when resin is injected. The ejector 24 is a device for ejecting a solidified and finished product from the mold 21. The fixed plate 25 is a plate to which the fixed side of the mold 21 can be attached. The movable plate 26 is a plate to which the movable side of the mold can be attached.

  The mold clamping device 30 includes a toggle 31. It is a device for opening and closing molds and clamping, and the force can be increased by a link mechanism with the movable platen 26.

  A method for producing a resin molded product using the injection molding machine 100 will be described.

  First, a resin material is put into the hopper 11 of the injection device 10. The resin material is extruded from the nozzle 14 through the screw cylinder 12. At this time, the resin material is heated and melted by the heater 13 and is sufficiently mixed to prepare a molten resin.

  The position of the injection device 10 is adjusted, and the tip of the nozzle 14 is brought into contact with and closely attached to the gate 23 of the mold part 20. From the nozzle 14, the molten resin can be injected into the cavity 22 from the gate 23. After the injected molten resin is solidified as it is in the mold 21, the resin molded product is removed from the mold 21 with the ejector 24, and the series of steps is completed.

  Before injecting molten resin from the injection apparatus 10 into the mold part 20, the mold clamping apparatus 30 is operated. This is because burr generation of the resin molded product is prevented by using the mold 21 as a high-pressure mold clamp.

  As a resin material to be put into the hopper 11, a glass piece-containing material and a thermoplastic resin pellet are used at a predetermined ratio.

  The thermoplastic resin pellets are, for example, polyamide (PA), polycarbonate (PC), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polystyrene (PS), polyvinyl chloride (PVC), acrylic or methacrylic (PMMA), polyethylene Pellets of thermoplastic resin such as terephthalate (PET) are used.

  As the glass piece of the glass piece-containing material, glass fiber or glass flake is used. The glass fiber has a diameter of 5 μm to 100 μm and a length of 0.1 mm to 10 mm. The glass flakes have a particle size of 5 μm to 10000 μm.

  It mixes so that the ratio of a glass piece may be 1 to 80% with respect to a thermoplastic resin pellet.

  The glass piece can be colored glass as well as colorless glass. It is obtained by adding metal oxides of metals such as cobalt, chromium and copper (sometimes sulfides and chlorides) to glass raw materials such as soda lime glass. In addition to using metal ions, it can be colored with non-metal ions or metal colloids, and different colors can be given depending on the melting conditions of the glass. For example, purple is a combination of (manganese and copper, cobalt), blue is a combination of (cobalt, copper), red is a combination of (gold, copper, cobalt, selenium and cadmium), and the like.

  Further, the glass piece may be a combination of colorless glass and colored glass, or a plurality of colored glass colors may be used. Moreover, you may combine gloss pieces, such as a glass flake which carried out metal coating with pearl powder, titanium, silver, etc. to the glass piece of several colors. Including these, it is called a glass piece-containing material. In this case, it mixes so that the ratio of the glass piece containing material containing a glossy piece may be 1-80% with respect to a thermoplastic resin pellet.

  3 and 4 are plan views showing patterns of the resin molded product. The tip of the arrow in the figure indicates the resin injection location by the gate 23. The thick line in the figure indicates the glass piece-containing material.

  The gate 23 is usually provided near the center of the cavity 22 so that resin can be injected evenly. In the injection molding machine 100 according to the present embodiment, first, the gate 23 is provided near the end of the cavity 22 as shown in FIG.

  When the thermoplastic resin which concerns on a related technique is used, as shown in FIG. 3, the whole surface becomes a uniform pattern. In addition to the non-pattern, when it is glossy or has a glitter, it is not a characteristic pattern but a uniform pattern.

  When the resin is injected under the same conditions as in FIG. 3 using the glass piece-containing material and the thermoplastic resin pellet according to the technique of the present invention, the entire surface is uniform as shown in FIG. 3 depending on the type of the resin. Pattern. Also, the direction of the gate 23 is changed to change the direction of resin injection, the size of the gate 23 is changed to change the amount of resin injection, a combination of materials selected from glass piece-containing materials and thermoplastic resin pellets to be used, Depending on the mixing ratio at that time, a wavy pattern as shown in FIG. 4 can be applied. The flow rate of the raw material is adjusted in advance based on the result of the flow rate analysis performed in advance.

  FIG. 5 is a plan view showing a pattern of a resin molded product. In FIG. 4, there is one gate 23, but FIG. 5 shows an example in which resin is molded with four gates 23. When a plurality of gates are provided, a symmetrical pattern can be formed as shown in the figure by simultaneously injecting resin from each gate.

  For example, the gate 23 on the nozzle 14 side (the side where the resin enters) has one hole, but the gate 23 on the mold 21 (the side where the resin exits) has four holes. In this way, the shape of the gate 23 is deformed. In addition, four gates 23 themselves are formed. In this case, it is necessary to form four corresponding nozzles 14. Any method can be used as long as the resin can be injected from each gate while the tip of the nozzle 14 is in close contact with the gate 23.

  FIG. 6 is a schematic configuration diagram illustrating an example of an injection molding machine used for molding a resin molded product according to a modification of the embodiment of the present invention. The basic structure of the injection molding machine 100 according to the modification is the same as that of the injection molding machine 100 of FIG.

  The injection molding machine 101 includes an injection device 10a, a mold part 20, and a mold clamping device 30.

  The injection device 10a includes a hopper 11a and a hopper 11b, a screw cylinder 12a and a screw cylinder 12b, a heater 13, a nozzle 14a and a nozzle 14b. The hopper 11a, the screw cylinder 12a, and the nozzle 14a are connected in series, and the hopper 11b, the screw cylinder 12b, and the nozzle 14b are also connected in succession. The positions of the two nozzles 14 a and 14 b are provided so that the tips of the nozzles 14 a and 14 b can be in close contact with the gate 23 during resin injection.

  The hopper 11a is filled with a glass piece-containing material and thermoplastic resin pellets, and the hopper 11b is injected with only thermoplastic resin pellets. As with materials, materials can be selected and charged.

  The injection molding machine 101 includes two continuous mechanisms including a hopper 11, a screw cylinder 12, and a nozzle 14, but a plurality of mechanisms may be provided. Moreover, as for the resin to be charged into the hopper 11, it is only necessary to add the glass piece-containing material and the thermoplastic resin pellet for at least one hopper, and for the other hoppers 11, only the thermoplastic resin pellet may be used. And thermoplastic resin pellets.

  Although the case where one gate 23 is provided for a plurality of nozzles 14 is taken as an example, the injection molding machine 101 may be configured to include the same number of gates 23 as the nozzles 14. The nozzle 14 is located at a portion from the hopper 11 through the screw cylinder 12 and is a portion for extruding a resin made of a material charged into the hopper 11. The nozzle 14 needs to inject the resin while being in close contact with the gate 23, and the number of the nozzles 14 and the gates 23 is the same, and the gates 23 are formed at positions corresponding to the nozzles 14. Can be adhered to. In addition, by making the number of nozzles 14 and gates 23 the same, the type of resin injected into the cavity 22 and the resin injection position relationship become clear. As a result, it becomes easy to form an arbitrary pattern.

  7 and 8 are plan views showing patterns of the resin molded product. It is possible to draw the illustrated pattern by injecting the resin for applying the pattern while injecting the resin of the base portion. By making the injection speed of the resin for attaching the pattern made of the glass piece-containing material and the thermoplastic resin pellet faster than the injection speed of the base resin made of the thermoplastic resin pellet, and depending on the amount and angle of injection, Various patterns can be drawn. The flow rate of the raw material is adjusted in advance based on the result of the flow rate analysis performed in advance.

  FIG. 9 is a plan view showing a pattern of a resin molded product. This is a case where one kind of resin as a base made of thermoplastic resin pellets and two kinds of resins for applying a pattern made of glass piece-containing material and thermoplastic resin pellets are prepared to be a total of three kinds of resins. Prepare two gates, and simultaneously inject the base resin and the resin for patterning into the mold from each gate. Alternatively, a base resin made of thermoplastic resin pellets and a resin for attaching a pattern made of a glass piece-containing material and a thermoplastic resin pellet are prepared. Half of each of the base resin and the resin for patterning is poured into the mold simultaneously from the two prepared gates. Similarly to FIGS. 7 and 8, the pattern is formed by making the injection rate of the resin for applying the pattern faster than the injection rate of the base resin.

  As described above, according to the present embodiment, it is possible to provide a resin molded product that is easy to manufacture and has high designability, and a manufacturing method thereof.

  By using the resin molded product according to the present embodiment, it is possible to give a beautiful decorative expression, and as a result, it is not necessary to apply coating or the like on the surface of the molded product, and ensure superiority to the environment and cost. It becomes possible.

  Moreover, even if an injection molding machine of a related technique is used, various patterns can be easily applied depending on the types and combinations of the glass piece-containing material and the thermoplastic resin pellet used, and their mixing ratio.

  Furthermore, different patterns can be formed by changing the injection rate, injection angle, and number of gates of the resin from the gate of the injection molding machine. Even if the temperature at which the resin is melted, the physical properties of the melted resin, such as viscosity, differ, so that different patterns can be formed. Furthermore, it is possible to increase the number of hoppers of the injection molding machine and increase the types of resin for applying the pattern.

  The above-described example is an example, and both the function of the injection molding machine and the selection of the resin can be arbitrarily set, and various patterns can be applied.

  A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.

(Additional remark 1) The process which throws in the resin material which consists of a glass piece containing material and a thermoplastic resin pellet from the hopper in an injection device, the process which heats and melts the said resin material with a heater in a screw cylinder, The said screw cylinder The molten resin material is injected into the mold cavity through the step of extruding the molten resin material toward the mold from the nozzle at the tip of the mold and the mold gate located in contact with the nozzle. A step of solidifying the resin material in the mold;
A method for producing a resin molded product comprising:

  (Supplementary Note 2) The injection apparatus includes a plurality of the hoppers, a plurality of screw cylinders, and a plurality of the nozzles, and the step of adding the glass piece-containing material and the thermoplastic resin pellets from at least one of the hoppers. The step of charging and extruding extrudes the molten resin material charged into each hopper from the different nozzles via the screw cylinders, and the step of injecting the molten resin material extruded in a predetermined order. The method for producing a resin molded product according to appendix 1, wherein each of the nozzles and the gate of the mold comes into contact with each other.

  (Additional remark 3) The said injection | pouring process inject | pours the said resin material from the some gate of the said metal mold | die which contacts the said nozzle, The manufacturing method of the resin molded product of Additional remark 1 or 2 characterized by the above-mentioned.

  (Additional remark 4) The resin molded product manufactured by the manufacturing method in any one of Additional remark 1 thru | or 3.

10, 10a Injection device 11, 11a, 11b Hopper 12, 12a, 12b Screw cylinder
13 Heater 14, 14a, 14b Nozzle
20 Mold part
21 Mold
22 cavities
23 Gate
24 Ejector
25 Fixed platen
26 Movable platen
30 Mold clamping device
31 Toggle 100, 101 Injection molding machine

Claims (4)

A step of feeding a resin material comprising a glass piece-containing material and a thermoplastic resin pellet from a hopper in an injection device;
Heating and melting the resin material with a heater in a screw cylinder;
A step of extruding the molten resin material from the nozzle at the tip of the screw cylinder toward the mold;
Injecting the molten resin material into the cavity of the mold through the gate of the mold located in contact with the nozzle;
Solidifying the resin material in the mold;
A method for producing a resin molded product comprising: The injection device includes a plurality of the hoppers, a plurality of the screw cylinders, and a plurality of the nozzles.
In the step of charging, the glass piece-containing material and the thermoplastic resin pellet are charged from at least one of the hoppers,
The extruding step extrudes the molten resin material charged into each hopper from the different nozzles through the screw cylinders,
2. The resin molded product according to claim 1, wherein the injecting step injects the molten resin material extruded in a predetermined order when each nozzle and the gate of the mold are in contact with each other. Production method.   The method of manufacturing a resin molded product according to claim 1, wherein the injecting step injects the resin material from a plurality of gates of the mold in contact with the nozzle.   The resin molded product manufactured with the manufacturing method of any one of Claim 1 thru | or 3.

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