JP2012131146A - Multicolor molded article and multicolor molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multicolor molded article and a multicolor molding method in which the molded article having a proper bond strength is molded even when adhesion compatibility between a first molding resin of primary molding and a second molding resin of secondary molding is not good.SOLUTION: The multicolor molded article includes: an optical element 1 molded by injection molding of the first molding resin; a colored outer peripheral part 2 arranged apart from the optical element 1 and molded by injection molding of the second molding resin different from the first molding resin; and an intermediate layer (third molding part) 3 arranged between the optical element 1 and the colored outer peripheral part 2 and molded by injection molding of a third molding resin different from the first molding resin and the second molding resin between the optical element 1 and the colored outer peripheral part 2. A first thermofusion bonded part 5 and a second thermofusion bonded part 6 which are bonded while being thermally fused and mixed are provided in a bonding interface between the optical element 1 and the intermediate layer 3 and a bonding interface between the intermediate layer 3 and the colored outer peripheral part 2, respectively.

Description

  The present invention relates to a multicolor molded product and a multicolor molding method in which a plurality of different resins are combined and integrated.

  Generally, in injection molding, there is a two-color molding technique as a technique for combining and integrating two different resins. This technique comprises a step of forming a primary molded part by injection molding and then injecting a secondary molding resin onto the primary molded part and integrating them to obtain a molded product. The problem with this two-color molding technique is the adhesiveness of the joint portion of the resin. This adhesion is greatly influenced by the compatibility of the primary molding resin and the secondary molding resin. In some cases, the combination of the primary molding resin and the secondary molding resin may not be combined. In such a case, a two-color molded product cannot be obtained.

  In order to solve such a problem, in Patent Document 1 and Patent Document 2, the joint area of the two-color joint portion is increased by providing irregularities in the two-color joint portion between the primary molding portion and the secondary molding portion. And the method of improving adhesiveness is proposed.

JP 2004-66655 A JP 2004-1424 A

  However, if the primary molding resin combined with the secondary molding resin is not compatible with the two-color molding and the resin at the two-color joint does not melt, the contact area is reduced as in the methods of Patent Documents 1 and 2. Even if the size is increased, sufficient effects cannot be obtained. Therefore, it becomes difficult to join the two-color joint between the primary molding part and the secondary molding part with an appropriate joint strength, and there is a possibility that a two-color molded product cannot be obtained.

  The present invention has been made by paying attention to the above circumstances, and its purpose is to provide an appropriate bonding strength even when the compatibility between the first molding resin of the primary molding and the second molding resin of the secondary molding is poor. An object of the present invention is to provide a multicolor molded product and a multicolor molding method capable of molding a molded product.

In one aspect of the present invention, a first molding part formed by injection molding a first molding resin and a second molding different from the first molding resin are arranged apart from the first molding part. A second molding part formed by injection molding of resin, and a third molding that is disposed between the first molding part and the second molding part and is different from the first molding resin and the second molding resin. A third molded part formed by injection molding a resin between the first molded part and the second molded part, and a bonding interface between the first molded part and the third molded part, and This is a multi-color molded product provided with a hot melt bonded portion bonded in a state of being melted and mixed at the bonding interface between the third molded portion and the second molded portion.
In the above-described configuration, the first molding part formed by injection molding of the first molding resin and the second molding resin different from the first molding resin, which is arranged apart from the first molding part, are injected. A third molding resin different from the first molding resin and the second molding resin is disposed between the first molding portion and the second molding portion, and is disposed between the second molding portion formed by molding. A third molded part formed by injection molding is provided, and a hot melt bonded part bonded in a melted and mixed state is provided at the bonding interface between the first molded part and the third molded part. By providing a hot melt bonded portion bonded in a state of being melted and mixed at the bonding interface between the second molded portion and the third molded portion, the first molded resin for primary molding and the second for secondary molding are provided. Even if the compatibility with the molding resin is poor, it is possible to mold a molded product with appropriate bonding strength. It is.

Preferably, the third molding resin has a resin characteristic that is bonded to a resin characteristic of the first molding resin and the second molding resin.
Preferably, an optical element is arranged by the first molding part, a frame part around the optical element by the second molding part, and an intermediate layer arranged between the optical element and the frame part by the third molding part. Each is formed.

  According to another aspect of the present invention, a first molding step of forming a first molding part by injection molding a first molding resin, the first molding resin and the first molding resin are disposed apart from the first molding part. A second molding step of forming a second molding part by injection molding a different second molding resin, and a third molding resin different from the first molding resin and the second molding resin to the first molding part and the second molding resin. A third molding step of forming a third molding part disposed between the first molding part and the second molding part by injection molding between the second molding part and the first molding part. The multicolor molding in which the molding step, the second molding step, and the third molding step are performed in the order of low melting temperatures of the first molding resin, the second molding resin, and the third molding resin. This is a method of molding a product.

  According to the present invention, it is possible to provide a multicolor molded product and a multicolor molding method by which a molded product having an appropriate bonding strength can be formed even when the adhesion between the primary molded resin and the secondary molded resin is poor. it can.

The multicolor molded product of the 1st Embodiment of this invention is shown, (A) is a top view which shows a multicolor molded product, (B) is the IB-IB sectional view taken on the line of (A). The top view which shows the arrangement | positioning state of the shaping | molding die on the movable platen of the molding machine of 1st Embodiment. FIG. 3 is a cross-sectional view taken along line A-O-B in FIG. 2. FIG. 3 is a sectional view taken along line B-O-C in FIG. 2. The longitudinal cross-sectional view which shows the state which moved the injection mold of 1st Embodiment to the mold opening position. The longitudinal cross-sectional view which shows the state which fills a secondary molding die with the 2nd molding resin in the state which the injection mold of 1st Embodiment moved to the mold closing position, and shape | molds a colored outer peripheral part. The mold of the first embodiment is opened again, and the secondary molding gate is separated while leaving the optical element portion and the colored outer peripheral portion in the movable mold of the first mold, and at the same time, the first mold is movable. The longitudinal cross-sectional view which shows the state which cut | disconnected the primary shaping | molding gate from the optical element part, and rotated the movable platen 120 degrees, leaving the optical element part in a type | mold. The intermediate molding die according to the first embodiment is filled with an intermediate resin to form an intermediate portion, and the optical element portion and the colored outer peripheral portion are integrated to obtain a multicolor molded product. The longitudinal cross-sectional view which shows the state which fills with molding resin. Open the molding die of the first embodiment, and in the intermediate molding die, leave the multi-color molded product in the movable die, and cut off the intermediate molding gate. At the same time, in the secondary molding die, remove the multi-color molded product from the movable die. The longitudinal cross-sectional view which shows the state which takes out the protrusion multicolor molded product. The flowchart for demonstrating the drive procedure of the injection mold of 1st Embodiment is shown, (A) is a flowchart for demonstrating the drive procedure of the whole injection mold, (B) is the drive of a primary mold. The flowchart for demonstrating a procedure, (C) is a flowchart for demonstrating the drive procedure of a secondary shaping | molding die, (D) is a flowchart for demonstrating the drive procedure of a tertiary shaping | molding die. The top view which shows the arrangement | positioning state of the injection mold on the movable platen of the molding machine of the 2nd Embodiment of this invention. FIG. 12 is a cross-sectional view taken along line A-O-B in FIG. 11. The longitudinal cross-sectional view which shows the state which opened the mold, leaving the optical element part in the injection mold of 2nd Embodiment in a movable mold | type. With the injection mold of the second embodiment moved to the mold closing position, the movable platen is rotated and the multicolor mold is moved to the position B, and the second molding resin is filled to fill the colored outer peripheral portion. The longitudinal cross-sectional view which shows the state obtained. The longitudinal cross-sectional view which shows the state which opened the type | mold again of the injection mold of 2nd Embodiment, and cut | disconnected the secondary shaping | molding gate, leaving the optical element part and the coloring outer peripheral part in a movable mold | type. Close the injection mold of the second embodiment, rotate the movable platen and move the multicolor mold to the position C, and fill the intermediate molding resin between the optical element part and the colored outer peripheral part. The longitudinal cross-sectional view which shows the state which forms an intermediate part and integrates an optical element part and a colored outer peripheral part, and obtains a multicolor molded product. The longitudinal cross-sectional view which shows the state which takes out a multicolor molded product after cutting off an intermediate | middle molding gate, leaving the multicolor molded product in a movable mold at the end of the process in the injection mold of 2nd Embodiment. The 3rd Embodiment of this invention is shown, (A) is a top view which shows a multicolor molded product, (B) is the 18B-18B sectional view taken on the line of (A). The longitudinal cross-sectional view which shows the multicolor molded product of the 4th Embodiment of this invention.

[First Embodiment]
(Constitution)
1 to 10 show a first embodiment of the present invention. FIG. 1A is a top view of a multicolor molded product 4 which is a resin molded product of the present embodiment. FIG. 1B is a cross-sectional view taken along line 1B-1B of FIG. FIG. 2 is a plan view of the entire multicolor molding die (molding die) 11 for molding the multicolor molded product 4.

  As shown in FIGS. 1A and 1B, the multicolor molded product 4 of the present embodiment includes an optical element (first molded portion) 1 that is, for example, an optical lens, and a lens that holds the optical element 1. A cylindrical colored outer peripheral portion (second molded portion) 2 that is a frame, and a ring-shaped intermediate layer (third molded portion) 3 disposed between the optical element 1 and the colored outer peripheral portion 2 are provided. It is formed by a single piece integrated by color molding. Here, the optical element 1 is formed by injection molding a first molding resin that is a light-transmitting resin material. The colored outer peripheral portion 2 is disposed away from the optical element 1 and is formed by injection molding a second molding resin different from the first molding resin. The intermediate layer 3 is disposed between the optical element 1 and the colored outer peripheral portion 2, and a third molding resin different from the first molding resin and the second molding resin is used as the optical element 1 and the colored outer peripheral portion 2. It is formed by injection molding.

  And these optical elements 1, the colored outer peripheral part 2, and the intermediate | middle layer 3 are multicolor-molded by the injection mold 21 shown in FIGS. 2-4, and the multicolor molded article 4 is shape | molded. Here, at the time of injection molding of the multicolor molded product 4, the first heat-melting joint portion 5 joined in a state of being melted and mixed at the joining interface between the optical element 1 and the intermediate layer 3 is formed, Similarly, a second hot melt joint portion 6 is formed at the joint interface between the intermediate layer 3 and the colored outer peripheral portion 2 and joined in the state of being melted and mixed. In the present embodiment, the thickness of the intermediate layer 3 is 0.3 mm.

  As shown in FIG. 1B, the optical element 1 has two surfaces facing each other, and these two surfaces become optical function surfaces 1a and 1b, respectively. In FIG. 1B, the upper side is a first optical functional surface 1a having a convex curved surface, and the lower side is a second optical functional surface 1b having a convex curved surface. The colored outer peripheral portion 2 functions as positioning in the lens barrel when the multicolor molded product 4 is attached to a lens barrel (not shown). In the present embodiment, the first molding resin of the optical element 1 is PC (polycarbonate), the second molding resin of the colored outer peripheral portion 2 is PS (polystyrene), and the third molding resin of the intermediate layer 3 is PMMA (acrylic).

  The third molding resin has a resin characteristic that binds to the resin characteristics of the first molding resin and the second molding resin. For example, the combinations shown in 1 to 8 in Table 1 below are suitable. In Table 1, the numbers in parentheses indicate the order of injection molding.

図２は、図示しない射出成形機の可動プラテン１２の上の多色成形型１１の配置状態を示す平面図である。多色成形型１１は、１次成形型１１Ａと、２次成形型１１Ｂと、中間成形型１１Ｃとを有する。これら３つの成形型１１Ａ〜１１Ｃは、可動プラテン１２の上に１２０°間隔で配置されている。また、その可動プラテン１２の中央には回転軸１３があり、この回転軸１３を中心に可動プラテン１２が回転する。

FIG. 2 is a plan view showing an arrangement state of the multicolor molding die 11 on the movable platen 12 of an injection molding machine (not shown). The multicolor mold 11 includes a primary mold 11A, a secondary mold 11B, and an intermediate mold 11C. These three molds 11A to 11C are arranged on the movable platen 12 at intervals of 120 °. In addition, there is a rotating shaft 13 at the center of the movable platen 12, and the movable platen 12 rotates around the rotating shaft 13.

  3 is a cross-sectional view taken along the line A-O-B in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line B-O-C in FIG. As shown in FIG. 3, the primary mold 11A is configured by combining a primary fixed mold 13a and a movable mold 14 with a PL (parting line) interposed therebetween. The secondary mold 11B is configured by combining the secondary fixed mold 13b and the movable mold 14 with the PL interposed therebetween. As shown in FIG. 4, the intermediate mold 11 </ b> C is configured by combining the intermediate fixed mold 13 c and the movable mold 14. The movable mold 14 has the same configuration in the primary mold 11A, the secondary mold 11B, and the intermediate mold 11C. Therefore, the same parts are denoted by the same reference numerals, and the description thereof is omitted.

As shown in FIG. 3, the primary fixed mold 13a includes a primary fixed side mounting plate 15a, a primary fixed side dropping plate 16a, and a primary fixed side mold plate 17a. A primary fixed insert 18a is inserted into the central portion of the primary fixed side template 17a.
The movable mold 14 facing the primary fixed mold 13 a includes a movable mold plate 19, a movable receiving plate 20, a spacer block 21, and a movable mounting plate 22. Inside the spacer block 21, an ejector plate 23 constituting a protruding mechanism is provided. Four ejector pins 24 are attached to the ejector plate 23. A movable insert 25 is inserted into the central portion of the movable side template 19. That is, the movable insert 25 is inserted into the movable mold 14. The movable nest 25 is arranged so as to face the primary fixed nest 18a at a distance.

  Further, when the primary fixed mold 13a of the primary mold 11A and the movable mold 14 are clamped (see FIGS. 3 and 4), a primary molded body is formed between the primary fixed mold 13a and the movable mold 14. A primary molding cavity portion 26 necessary for molding a certain optical element 1 is formed. The primary molding cavity portion 26 includes a primary fixed side molding surface 18a1 of a concave curved surface shape of the primary fixed insert 18a, a concave portion 17a1 for forming a primary cavity of the primary fixed side mold plate 17a, and a movable input of the movable side mold plate 19. It is formed by a sealed space between the movable side molding surface 25 a having a concave curved surface on the upper surface of the child 25 and the movable side template 19.

  Further, primary molding for supplying the molten material, which is the molding material of the optical element 1 as the primary molded body, in the center opening position to the primary fixed side mounting plate 15a and the primary fixed side dropping plate 16a of the primary fixed mold 13a. Each primary sprue 27a is formed. Further, the primary fixed side template 17a is provided with a primary molding runner 28a, a primary molding secondary sprue 29a, and a primary molding pinpoint gate 30a for filling the primary molding cavity portion 26 with resin. ing.

  When molding the optical element 1 that is the primary molded body, the molten material of the first molding resin that is the molding material of the optical element 1 is the primary sprue 27a for primary molding for the primary fixed side mounting plate 15a and the primary fixed side drop plate 16a. From the primary molding side runner 28a, the primary molding secondary sprue 29a, and the primary molding pin point gate 30a, the primary molding cavity portion 26 is filled with the primary molding side mold plate 17a. The first molding resin is filled into the primary molding cavity 26, and then cooled to mold the optical element 1.

In addition, a primary fixed side temperature control tube 31a is disposed on the primary fixed side template 17a. In the primary fixed side temperature control pipe 31a, a medium whose temperature is adjusted, such as water or oil, is accommodated in a state where it always flows during molding.
Further, the movable side template 19 has a secondary side of the colored outer peripheral portion 2 that is the second molding portion concentrically with the mold axis center of the movable side template 19 on the side facing the PL at the outer peripheral portion of the movable insert 25. A movable side space 32 for forming a part of the molding cavity is formed. Then, four ejector pins 24 are arranged so as to be in contact with the bottom surface of the movable side space 32.

  The secondary fixed mold 13b includes a secondary fixed side mounting plate 15b, a secondary fixed side dropping plate 16b, and a secondary fixed side mold plate 17b. A secondary fixed insert 18b is fitted into the secondary fixed side template 17b. The movable mold 14 facing the secondary fixed mold 13b has the same configuration as the movable mold 14 facing the primary fixed mold 13a as described above.

  Secondary fixing for forming a part of the secondary molded body cavity of the colored outer peripheral portion 2 as the second molded portion on the lower surface of the secondary fixed side template 17b at the portion corresponding to the secondary fixed insert 18b. A side space 33 is formed. The secondary fixed side space 33 of the secondary fixed side mold plate 17 b is formed at a position facing the movable side space 32 of the movable side mold plate 19.

  3 and 4, when the movable mold 14 and the secondary fixed mold 13b of the secondary mold 11B are clamped, the secondary fixed side space 33 on the lower surface of the secondary fixed mold plate 17b is A secondary molding cavity 34 for second molding of the colored outer peripheral portion 2 is formed around the optical element 1 in communication with the movable side space 32 of the movable side template 19.

  Further, the secondary fixed side mounting plate 15b and the secondary fixed side dropping plate 16b of the secondary fixed mold 13b are melted with a second molding resin that is a molding material of the colored outer peripheral portion 2 that is a secondary molded body at the center position. Secondary forming primary sprues 27b for supplying the material in the mold opening direction are respectively formed. Further, the secondary fixed side mold plate 17b has a secondary fixed side space 33 which becomes a secondary forming cavity 34 through a secondary forming runner 28b and a secondary forming secondary sprue 29b, and a movable portion. A secondary molding pinpoint gate 30b for filling the side space 32 with resin is provided.

  The secondary molding die 11B is a primary molding die 11A that is used after the optical element 1 that is a primary molded body is primary molded. That is, when the optical element 1 that is a primary molded body is primary molded by the primary molding die 11A, the primary molded optical element 1 is left in a state of being held by the movable mold 14. Then, after the movable mold 14 and the primary fixed mold 13a are opened, the movable mold 14 holding the primary molded optical element 1 and the secondary fixed mold 13b of the secondary mold 11B are clamped. The As a result, when the secondary fixed mold 13b and the movable mold 14 of the secondary mold 11B are clamped, the optical element 1 as a primary molded body is set between the secondary fixed mold 13b and the movable mold 14 in advance. The

  And between the secondary fixed mold | type 13b and the movable mold | type 14, the movable side arrange | positioned on both sides of PL between the secondary fixed side space 33 of the secondary fixed mold | type 13b, and the movable side mold plate 19 of the movable mold | type 14 A secondary molding cavity 34 for secondary molding of the colored outer peripheral portion 2 is formed around the optical element 1 which is a primary molded product in communication with the space 32. The colored outer peripheral portion 2 is secondary molded by filling the secondary molding cavity 34 with the second molding resin.

Further, a secondary fixed side temperature control tube 31b is disposed on the secondary fixed side template 17b. A medium whose temperature is adjusted, such as water or oil, is accommodated in the secondary fixed side temperature control pipe 31b at the time of molding.
As shown in FIG. 4, the intermediate fixed mold 13c has an intermediate fixed side mounting plate 15c, an intermediate fixed side dropping plate 16c, and an intermediate fixed side mold plate 17c. An intermediate layer forming cavity 34 for forming the intermediate layer 3 is formed in the intermediate fixed side template 17c. As described above, the movable mold 14 facing the intermediate fixed mold 13c has the same configuration as the movable mold 14 facing the primary fixed mold 13a and the secondary fixed mold 13b.

  Further, the intermediate fixing side mounting plate 15c and the intermediate fixing side dropping plate 16c of the intermediate fixing mold 13c are opened with a molten material of a third molding resin, which is a molding material of the intermediate layer 3 as the third molding portion, at the center position. Intermediate forming primary sprues 27c to be supplied in the direction are formed respectively. Further, an intermediate layer forming mold for filling the intermediate layer forming cavity 34 with resin through the intermediate layer forming runner 28c and the intermediate layer forming secondary sprue 29c in this order on the intermediate fixed side template 17c. A pinpoint gate 30c is provided.

In this embodiment, the intermediate molding die 11C is a primary molding die 11A in advance, and the optical element 1 that is a primary molding is first molded, and then the colored outer peripheral portion 2 that is a primary molding is formed in the secondary molding die 11B. Used after subsequent molding.
In addition, an intermediate fixed side temperature control tube 31c is disposed on the intermediate fixed side template 17c. A medium whose temperature is adjusted, such as water or oil, is accommodated in the intermediate fixed side temperature control tube 31c in a state where it is always flowing during molding.

(Function)
Next, the molding process of the multicolor molded product 4 of the present embodiment will be described with reference to the flowcharts shown in FIGS. FIG. 10A is a flowchart for explaining the entire driving procedure of the multi-color molding die 11, FIG. 10B is a flowchart for explaining the driving procedure of the primary molding die 11A, and FIG. 10C. Is a flowchart for explaining the driving procedure of the secondary molding die 11B, and FIG. 10D is a flowchart for explaining the driving procedure of the tertiary molding die 11C.

  When the multicolor mold 11 is used, as shown in step S1 of the flowchart in FIG. 10A, the melting temperatures of the three resins used are compared and ranked. And the 1st shaping | molding process which primarily shape | molds resin with the lowest melting temperature is performed (step S2). Next, a second molding step is performed in which a resin having the second lowest melting temperature is secondarily molded (step S3). Subsequently, a third molding step is performed in which the resin having the third lowest melting temperature is third-molded (step S4). After that, in the next step S5, it is determined whether or not the number of manufactured multicolor molded products 4 completed up to the third molding step can be secured in advance. Here, if it is not determined that the necessary number has been secured, the process returns to step S2. If it is determined in step S5 that the necessary number has been secured, the process ends.

  In the first molding step of step S2, the primary molding die 11A is used and the first molding step is performed as shown in the flowchart of FIG. 10B. Here, at the reference position in the initial state shown in FIG. 2, the primary fixed mold 13a and the movable mold 14 are moved to the mold closing position as shown in FIG. 3 (step S11). In this state, the primary fixed die 13a via the primary forming primary sprue 27a, the primary forming runner 28a, the primary forming secondary sprue 29a, and the primary forming pinpoint gate 30a in this state. And the movable mold 14 are filled with the first molding resin (step S12). Then, it cools and the optical element 1 (1st shaping | molding part) is primary-molded.

  After the primary molding of the optical element 1, the primary molding die 11A is opened (step S13). At the same time, the primary molding primary sprue 27a, the primary molding runner 28a, the primary molding secondary sprue 29a, and the primary molding pinpoint gate 30a, with the optical element 1 remaining in the movable die 14, are integrated. The (residual resin) 35 is separated from the optical element 1.

  Next, the movable platen 12 is rotated by 120 ° about the rotating shaft 13 (step S14: see FIG. 5). Thereby, a 1st shaping | molding process is complete | finished and then the 2nd shaping | molding process of step S3 is started. The integral 35 of the primary molding primary sprue 27a, the primary molding runner 28a, the primary molding secondary sprue 29a, and the primary molding pinpoint gate 30a is removed when the mold is opened.

  In the second molding step of step S3, the secondary molding die 11B is used and the second molding step is performed as shown in the flowchart of FIG. Here, in the state of FIG. 5, the primary fixed mold 13a and the movable mold 14 are opposed to close the mold, and at the same time, the secondary fixed mold 13b and the movable mold 14 are opposed to close the mold (step S21). At this time, the movable die 14 facing the secondary fixed die 13b is held with the optical element 1 remaining. Further, the movable die 14 facing the primary fixed die 13a is held without the optical element 1.

  Next, as shown in FIG. 6, the secondary molding die 11B is filled with the second molding resin in a state where the secondary fixed mold 13b and the movable mold 14 are moved to the mold closing position (step S22). At this time, the secondary fixed side which becomes the secondary molding cavity 34 through the secondary molding primary sprue 27b, the secondary molding runner 28b, the secondary molding secondary sprue 29b, and the secondary molding gate 30b. The space 33 and the movable side space 32 are filled with the second molding resin, and the colored outer peripheral portion 2 is molded.

In parallel with this operation, also in the primary mold 11A, the cavity 26 between the primary fixed mold 13a and the movable mold 14 is filled with the first molding resin as described above, and the optical element 1 is molded. (FIG. 6).
Thereafter, the mold opening is performed again (step S23). As shown in FIG. 7, in the secondary molding die 11B, the secondary molding primary sprue 27b, the secondary molding runner 28b, the second molding die 11B, leaving the optical element 1 and the colored outer peripheral portion 2 in the movable die 14. The integral (residual resin) 36 of the secondary molding secondary sprue 29b and the secondary molding gate 30b is cut off.

  At the same time, in the primary mold 11A, the primary sprue 27a for primary molding, the runner 28a for primary molding, the secondary sprue 29a for primary molding, and the pins for primary molding are left with the optical element 1 remaining in the movable mold 14. An integrated object (residual resin) 35 with the point gate 30 a is separated from the optical element 1.

  Thereafter, the movable platen 12 is rotated by 120 ° about the rotation shaft 13 (step S24: see FIG. 7). Thereby, the second molding process is completed, and then the third molding process of step S4 is started. At the time of the third molding step in step S4, the intermediate molding die 11C is used and the third molding step is performed as shown in the flowchart of FIG. Here, as shown in FIG. 8, the intermediate fixed mold 13c and the movable mold 14 are opposed to close the mold, and at the same time, the secondary fixed mold 13b and the movable mold 14 are opposed to close the mold (step S31). At this time, the movable die 14 facing the intermediate fixed die 13c is held in a state where the optical element 1 and the colored outer peripheral portion 2 remain. Further, the movable die 14 facing the secondary fixed die 13b is held with the optical element 1 remaining. At the same time, in the primary molding die 11A on the movable platen 12, the first molding process in step S2 is started.

  Next, as shown in FIG. 8, the intermediate molding die 11C is filled with the third molding resin in a state where the intermediate fixed die 13c and the movable die 14 are moved to the die closing position (step S32). At this time, the intermediate layer 3 is a molding material for the intermediate layer 3 via the intermediate molding primary sprue 27c, the intermediate layer molding runner 28c, the intermediate layer molding secondary sprue 29c, and the intermediate layer molding pinpoint gate 30c. The intermediate layer molding cavity 34 is filled with a molten material of three molding resins. Then, the intermediate layer 3 between the optical element 1 and the colored outer peripheral portion 2 is formed, and the optical element 1 and the colored outer peripheral portion 2 are integrated through the intermediate layer 3 to form a multicolor molded product 4. The

  In parallel with this operation, in the secondary molding die 11B, the secondary molding cavity 34 between the secondary fixed die 13b and the movable die 14 is filled with the second molding resin as described above, and the colored outer peripheral portion 2 is filled. Is secondary molded. At this time, in the primary mold 11A, the first molding resin is filled in the cavity portion 26 between the primary fixed mold 13a and the movable mold 14 as described above, and the optical element 1 is molded.

  Then, the final mold opening is performed (step S33). At this time, in the intermediate mold 11C, the intermediate molding primary sprue 27c, the intermediate layer molding runner 28c, the intermediate layer molding secondary sprue 29c, while the multicolor molded product 4 remains in the movable mold 14, An integrated body (residual resin) 37 with the layer forming pinpoint gate 30 c is separated from the intermediate layer 3.

  At the same time, in the secondary molding die 11B, the secondary molding primary sprue 27b, the secondary molding runner 28b, and the secondary molding secondary 2B are left while the optical element 1 and the colored outer peripheral portion 2 remain in the movable die 14. The integral (residual resin) 36 of the next sprue 29b and the secondary molding gate 30b is cut off. Further, in the primary molding die 11A, the primary sprue 27a for primary molding, the runner 28a for primary molding, the secondary sprue 29a for primary molding, and the pinpoint for primary molding, while leaving the optical element 1 in the movable die 14. The integrated object (residual resin) 35 with the gate 30 a is separated from the optical element 1.

  Thereafter, an ejector rod (not shown) existing in the molding machine is operated, and the ejector plate 23, the ejector pin 24, and the movable insert 25 are moved in conjunction therewith. Thereby, the multicolor molded product 4 on the movable mold 14 of the intermediate mold 11C is protruded from the movable mold 14, and a molded product takeout process for taking out the multicolor molded product 4 is performed (step S34).

  Thereafter, the movable platen 12 is rotated by 120 ° about the rotation shaft 13 (step S35). Thereby, a 3rd shaping | molding process is complete | finished and the shaping | molding process of the following multicolor molded product 4 is started. Thereafter, this operation is repeated. Then, in step S5 of the flowchart of FIG. 10A, the process ends when it is determined that the number of manufactured multicolor molded products 4 completed up to the third molding step has secured a preset required number.

(effect)
Therefore, the above configuration has the following effects. That is, in the multicolor molding die 11 of the present embodiment, PC is injected as the first molding resin in the primary molding, and after forming the optical element 1, PS is injected as the second molding resin in the secondary molding. The colored outer peripheral portion 2 is formed. Here, the optical element 1 made of the first molding resin and the colored outer peripheral portion 2 made of the second molding resin are separated from each other, and the first molding resin and the second outer periphery 2 are placed between the optical element 1 and the colored outer peripheral portion 2. A third molding resin (intermediate resin) having good compatibility with the molding resin is interposed.

  Further, in the multicolor mold 11 of the present embodiment, the portion into which the third molding resin enters is partitioned by the mold member of the multicolor mold 11. Thereafter, the mold member is changed to form a space for containing the third molding resin, filled with PMMA as the third molding resin to form the intermediate layer 3, and at the same time, the optical element 1 and the colored outer peripheral portion 2. Adhere closely. Accordingly, even the PC optical element 1 with poor adhesion and the colored outer peripheral portion 2 of PS can be bonded by interposing the PMMA intermediate layer 3 having high adhesion compatibility with each resin therebetween. In this way, by interposing a third molding resin (intermediate resin) that is compatible with each other's resin between the first molding resin and the second molding resin, a combination of resins having poor compatibility from the viewpoint of adhesion. Even if it exists, the multicolor molded article 4 with sufficient joint strength is obtained. As a result, a multicolor molded product and a multicolored product that can form a molded product having an appropriate bonding strength even when the compatibility between the first molded resin of the primary molding and the second molded resin of the secondary molding is poor A molding method can be provided.

  Furthermore, the resin used in the molding of the multicolor molded product 4 of the present embodiment is, for example, the first molding resin of the optical element 1 is PC, the second molding resin of the colored outer peripheral portion 2 is PS, and the intermediate layer 3 The third molding resin is PMMA. In general, PC which is the resin of the optical element 1 and PS which is the resin of the colored outer peripheral portion 2 have low adhesion at the bonding interface in the multicolor molding of PC and PS due to the compatibility of the resins. Therefore, in the present embodiment, after the PC of the first molding resin and the PS of the second molding resin of the optical element 1 are separated from each other, the first molding resin is molded separately and independently. A PMMA having good compatibility with both resins as a third molding resin is filled between the PC and the PS of the second molding resin. Thereby, the 1st heat fusion joint part 5 combined in the state melted and mixed in the joint interface of PC of the 1st molding resin and the 3rd molding resin, respectively, was provided, and similarly the 2nd molding resin By providing the second heat-melting joint portion 6 bonded in a state of being melted and mixed at the joint interface between the PS and the third molding resin, the optical element 1 and the colored outer peripheral portion 2 are connected to the third interface. It can be joined with sufficient adhesion strength through the intermediate layer 3 of the molding resin.

  In the present embodiment, it is preferable that PC and PS are melted at 270 ° C. and PMMA is melted at 290 ° C. and filled in the mold. In this way, the melting temperature of the third molding resin of the intermediate layer 3 to be finally filled is higher than the melting temperature of the first molding resin to be filled in the primary molding and the melting temperature of the second molding resin to be filled in the secondary molding. By setting the temperature, when the third molding resin of the intermediate layer 3 is filled, the resins at the interfaces of the intermediate layer 3, the optical element 1, and the colored outer peripheral portion 2 are well melted to improve the adhesion.

  That is, the molten resin melts at the joint between the first molding resin and the third molding resin to form the first hot melt bonding portion 5, and at the joint between the second molding resin and the third molding resin. The second hot melt bonded portion 6 is formed by melting the molten resins. As a result, the first molding resin of the transparent optical element 1 and the second molding resin of the colored outer peripheral portion 2 are bonded via the third molding resin of the intermediate layer 3.

In the present embodiment, the first molding resin is PC, the second molding resin is PS, and the intermediate molding resin is PMMA. However, the present invention is not limited to this. For example, the combination of resins shown in Table 1 may be used.
However, only in the case of the multicolor molded product 4 including the optical element 1 as in the present embodiment, the first molding resin of the optical element 1 is injection molded first, and then the third layer 3 of the intermediate layer 3 is formed. It is necessary to injection mold the molding resin or the second molding resin of the colored outer peripheral portion 2.

  This is because if the first molding resin of the optical element 1 is injection molded after the third molding resin of the intermediate layer 3 or the second molding resin of the colored outer peripheral portion 2, the third molding resin of the optical element 1 and the intermediate layer 3 is used. At the interface, the resin melts and joins. At that time, the first molding resin of the optical element 1 flows and fills while dissolving the third molding resin of the intermediate layer 3 or the second molding resin of the colored outer peripheral portion 2. Then, the third molding resin of the intermediate layer 3 and the second molding resin of the colored outer peripheral portion 2 are mixed into the transparent resin of the first molding resin of the optical element 1. In this case, the optical function of the optical element 1 may be impaired. For this reason, when the optical element 1 and the colored outer peripheral portion 2 are subjected to multicolor molding, it is essential to firstly perform the injection molding of the first molding resin of the optical element 1.

[Second Embodiment]
(Constitution)
11 to 17 show a second embodiment of the present invention. The present embodiment is a modification in which the configuration of the multicolor mold (molding mold) 11 of the first embodiment (see FIGS. 1 to 10) is changed as follows. The multicolor molded product 4 is the same as that in the first embodiment.

  That is, in the first embodiment, an example in which three molds, that is, the primary mold 11A, the secondary mold 11B, and the intermediate mold 11C are used on the movable platen 12, is shown. In the embodiment, as shown in FIG. 11, one mold 41 is provided on the movable platen 12. This is because, for example, when the production is a small quantity production, the cost of the molding die becomes large when the three molding dies 11A, 11B, and 11C are used as in the first embodiment, and the cost of the molding die becomes the manufacturing cost. The proportion occupied increases, resulting in an increase in manufacturing costs. Therefore, in the present embodiment, it is intended to reduce the manufacturing cost by enabling the multicolor molded product 4 to be molded with one mold.

  11 is a plan view showing an arrangement state in which the multicolor molding die 41 of the present embodiment is arranged on the movable platen 12 of the molding machine, and FIG. 12 is a cross-sectional view taken along line A-O-B in FIG. . In FIG. 11 to FIG. 17, the same parts as those in FIG. 1 to FIG. In the multicolor molding die 41 of the present embodiment, a partition plate 42 is provided on the movable die 14. The partition plate 42 is disposed at a portion corresponding to the cavity for the intermediate layer 3 and is provided on the movable side mold plate 19 so as to protrude and retract toward the fixed mold 13 side. The partition plate 42 is attached to the ejector plate 23 and moves in conjunction with the ejector plate 23.

  The fixed mold 13 of the multicolor mold 41 includes a fixed attachment plate 15, a fixed drop plate 16, and a fixed mold 17. A fixed insert 18 is fitted into the center portion of the fixed-side template 17. The fixed insert 18 includes a concave-curved fixed-side cavity molding surface 26a that constitutes a part of the cavity 26 of the optical element 1, and a recess that constitutes a part of the cavity 43 for the intermediate layer 3 (see FIG. 16). An intermediate layer cavity forming surface 43a is formed. Further, the fixed-side template 17 is formed with a concave-shaped colored outer peripheral cavity forming surface 44a constituting a part of the cavity 44 for the colored outer peripheral portion 2 on the peripheral wall portion of the hole into which the fixed insert 18 is inserted. ing.

  In addition, on the upper surface of the movable insert 25, a movable-side cavity molding surface 26b having a concave curved surface shape forming a part of the cavity 26 of the optical element 1 is formed. Furthermore, an insertion hole 45 for the partition plate 42 is formed in the movable side template 19 around the insertion hole for the movable insert 25. The insertion hole 45 is formed between the movable side space 32 for forming a part of the secondary molding cavity 44 of the colored outer peripheral portion 2 and the fitting insertion hole of the movable insert 25.

  Furthermore, the fixed side mounting plate 15 and the fixed side dropping plate 16 are provided with a sprue 46a through which the primary molding resin passes, a sprue 46b through which the secondary molding resin passes, and a sprue 46c through which the tertiary molding resin passes. Yes. These three sprues 46 a, 46 b and 46 c are arranged side by side along the radial direction of the movable platen 12.

  Further, the secondary molding resin is supplied to the stationary mold plate 17 and the primary molding resin supply passage 47 a for supplying the primary molding resin to the cavity 26 of the optical element 1 and the cavity 44 for the colored outer peripheral portion 2. The secondary molding resin supply passage 47b and the tertiary molding resin supply passage 47c for supplying the tertiary molding resin to the cavity 43 for the intermediate layer 3 are configured not to interfere with each other. The primary molding resin supply passage 47a is provided with a primary molding runner 48a, a primary molding secondary sprue 49a, and a primary molding pinpoint gate 50a. Similarly, a secondary molding runner 48b, a secondary molding secondary sprue 49b, and a secondary molding pinpoint gate 50b are provided in the secondary molding resin supply passage 47b (see FIG. 14). ). Further, a tertiary molding runner 48c, a tertiary molding secondary sprue 49c, and a tertiary molding pinpoint gate 50c are provided in the tertiary molding resin supply passage 47c (see FIG. 16). .

(Function)
Next, the operation of the above configuration will be described. The molding process of the multicolor molded product 4 of the present embodiment will be described. First, the multi-color molding die 41 is placed at the reference position in the initial state shown in FIG. At this position, as shown in FIG. 12, the molding die 41 is closed, and then an ejector rod (not shown) from the molding machine is operated to eject the ejector plate 23, the partition plate 42 connected thereto, and the ejector pin 24. Are advanced until the partition plate 42 abuts against the fixed-side mold plate 17.

  In this state, the first molding resin is filled into the cavity 26 of the optical element 1 from the primary molding sprue 46a through the primary molding runner 48a, the primary molding secondary sprue 49a, and the primary molding gate 50a. The optical element 1 is molded. Thereafter, the mold 41 is opened as shown in FIG. As a result, while the optical element 1 remains in the movable mold 14, the integrated body (residual resin) of the primary molding sprue 46a, the primary molding runner 48a, the primary molding secondary sprue 49a, and the primary molding gate 50a. ) 51 is separated from the optical element 1.

Thereafter, after closing the mold 41, the movable platen 12 is rotated, and the multicolor molding die 41 is moved to the position B in FIG. At this time, the ejector plate 23, the partition plate 42, and the ejector pin 24 are held while being advanced.
In this state, as shown in FIG. 14, the second molding resin is colored from the secondary molding sprue 46b through the secondary molding runner 48b, the secondary molding secondary sprue 49b, and the secondary molding gate 50b. 2 is filled in the secondary molding cavity 44, and the colored outer peripheral portion 2 is molded.

  Thereafter, as shown in FIG. 15, the multicolor mold 41 is opened again. Accordingly, the secondary molding sprue 46b, the secondary molding runner 48b, the secondary molding secondary sprue 49b, and the secondary molding gate 50b are left while the optical element 1 and the colored outer peripheral portion 2 remain in the movable die 14. The monolith (residual resin) 52 is separated from the colored outer peripheral portion 2.

  Thereafter, as shown in FIG. 16, after closing the multicolor mold 41, the movable platen 12 is rotated, and the multicolor mold 41 is moved to the position C in FIG. Here, the ejector rod from the molding machine is retracted, and the ejector plate 23, the partition plate 42 connected thereto, and the ejector pin 24 are retracted. The cavity 43 for the intermediate layer 3 is formed by the movement of the partition plate 42 at this time.

In this state, the third molding resin is transferred from the sprue 46c to the cavity 43 for the intermediate layer 3 through the third molding runner 48c, the third molding secondary sprue 49c, and the third molding pinpoint gate 50c. Fill and mold the intermediate layer 3.
The intermediate layer 3 is formed by filling between the optical element 1 and the colored outer peripheral portion 2 through the intermediate molding sprue 93, the intermediate molding runner 103, the intermediate molding secondary sprue 113, and the intermediate molding gate 123, and the optical element 1 and the coloring material. The outer peripheral part 2 is integrated and the multicolor molded product 4 is obtained.

  Finally, the intermediate layer 3, the intermediate molding sprue 93, the intermediate molding runner 103, the intermediate molding secondary sprue 113, and the intermediate molding gate 123 are separated while leaving the multicolor molded product 4 in the movable mold 14, and then again the molding machine The ejector rod is advanced, the ejector plate 23 and the partition plate 42 and the ejector pin 24 connected thereto are advanced, and the multicolor molded product 4 is taken out.

(effect)
Therefore, in the present embodiment, as in the first embodiment, the intermediate layer 3 having good compatibility with each other between the first molding resin of the optical element 1 and the second molding resin of the colored outer peripheral portion 2 is used. By interposing three molding resins (intermediate resins), a multicolor molded product 4 having sufficient bonding strength can be obtained even with a combination of resins having poor compatibility from the viewpoint of adhesion. As a result, a multicolor molded product and a multicolored product that can form a molded product having an appropriate bonding strength even when the compatibility between the first molded resin of the primary molding and the second molded resin of the secondary molding is poor A molding method can be provided.

  Furthermore, in the present embodiment, in addition to the effects of the first embodiment, a single mold 41 is provided on the movable platen 12 so that the multicolor molded product 4 can be molded with the single mold 41. The cost of the multicolor mold 41 can be reduced. As a result, the manufacturing cost of the multicolor molded product 4 can be reduced, and this is particularly effective in the case of small-volume production.

[Third Embodiment]
(Constitution)
18A and 18B show a third embodiment of the present invention. The present embodiment is a modification in which the configuration of the multicolor molded product 4 of the first embodiment (see FIGS. 1 to 10) is changed as follows.
That is, in the multicolor molded product 61 of the present embodiment, the inner peripheral surface of the colored outer peripheral portion 63 molded with the second molding resin is joined to the peripheral wall of the optical element 62 molded with the transparent first molding resin. A two-color molded product 64 arranged in a state is provided. Then, the intermediate layer 65 of the third molding resin is joined to one surface side of the optical element 62 of the two-color molded product 64 so as to overlap the joint portion between the optical element 62 and the colored outer peripheral portion 63. The intermediate layer 65 of the third molding resin is formed in a ring shape in a state of extending in the entire circumferential direction along the joint portion between the optical element 62 and the colored outer peripheral portion 63.

(Action / Effect)
Therefore, even in the above-described configuration, the third molding resin of the intermediate layer 65 having good compatibility with each other resin at the joint between the first molding resin of the optical element 62 and the second molding resin of the colored outer peripheral portion 63. (Intermediate resin) can be interposed. Also in this case, even if the first molding resin and the second molding resin are a combination of resins having poor compatibility from the viewpoint of adhesion, a multicolor molded product 61 having sufficient bonding strength can be obtained. As a result, a multicolor molded product capable of molding a multicolor molded product 61 having an appropriate bonding strength even when the compatibility between the first molded resin for primary molding and the second molded resin for secondary molding is poor. And a multicolor molding method can be provided.

[Fourth Embodiment]
(Constitution)
FIG. 19 shows a fourth embodiment of the present invention. The present embodiment is a modification in which the configuration of the multicolor molded product 4 of the first embodiment (see FIGS. 1 to 10) is changed as follows.
That is, the multicolor molded product 71 of the present embodiment is an example in which the present invention is applied to the operation button 72. FIG. 19 shows an operation button 72 formed by the multicolor molded product 71. The operation button 72 has a design part 73, a foot part 74, and an exterior part 75.

The design part 73 has a design function such as alphanumeric characters and symbols of .DELTA..DELTA. The foot part 74 has a function such as positioning for attaching the operation button 72 to another member. The exterior portion 75 has a function of an appearance portion other than the design portion 73.
In the present embodiment, for example, the design portion 73 is formed of a first molded resin for primary molding, and the foot portion 74 is formed of a second molded resin for secondary molding. Further, the third molding resin (intermediate resin) corresponds to the resin of the exterior portion 75, and this resin has good compatibility with the respective resins of the design portion 73 and the foot portion 74.

  In such a configuration, the combinations shown in Table 2 below can be considered for the resin used and the order of injection.

（作用・効果）
そこで、本実施の形態では意匠部７３の第１成形樹脂と足部７４の第２成形樹脂との間にお互いの樹脂と相性の良い外装部７５の第３成形樹脂（中間樹脂）を介在させることで、密着性の観点から相性の悪い樹脂の組合せであっても、十分な接合強度を有した多色成形品７１が得られる。さらに、本実施の形態の操作ボタン７２は、第１の実施の形態の光学素子とは違い樹脂の界面付近でお互いの樹脂が流れだしても部品機能上、大きな影響を与えない。そのため、第１成形樹脂および第２成形樹脂は意匠部７３、外装部６２のどちらにもなりえる。ただし、射出順序はそれぞれの溶融時の温度関係により決まり、溶融温度が低い樹脂から順に射出成形されている。

(Action / Effect)
Therefore, in the present embodiment, the third molding resin (intermediate resin) of the exterior portion 75 having good compatibility with each other resin is interposed between the first molding resin of the design portion 73 and the second molding resin of the foot portion 74. As a result, a multi-color molded article 71 having sufficient bonding strength can be obtained even with a combination of resins having poor compatibility from the viewpoint of adhesion. Further, unlike the optical element of the first embodiment, the operation button 72 of the present embodiment does not have a great influence on the component function even if the resin flows out in the vicinity of the resin interface. Therefore, the first molding resin and the second molding resin can be either the design portion 73 or the exterior portion 62. However, the injection order is determined by the temperature relationship at the time of melting, and injection molding is performed in order from the resin having the lowest melting temperature.

Furthermore, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.
Next, other characteristic technical matters of the present application are appended as follows.
Record
(Additional Item 1) An inner molded portion formed by injection molding a first molding resin, an outer molded portion formed by injection molding a second molding resin different from the first molding resin, and the first A multicolor having an intermediate part formed by injection molding an intermediate resin different from the molding resin and the second molding resin at a bonding interface between the primary molding part and the secondary molding part Molding.

(Additional Item 2) The multicolor molded article according to Additional Item 1, wherein the intermediate resin has a resin characteristic that is bonded to a resin characteristic of the first molding resin and the second molding resin.
(Additional Item 3) A method for molding a multicolor molded product according to claim 1, wherein an inner molding step of forming an inner molded portion by injection molding the first molding resin, and the second molding resin An outer molding step for forming an outer molded portion by injection molding; and an intermediate molding step for forming the intermediate portion by injection molding of the intermediate resin, the primary molding resin, the secondary molding resin, and the intermediate resin. Is a method for molding a multicolor molded product, wherein injection molding is performed in the order of the low melting temperatures.

  INDUSTRIAL APPLICABILITY The present invention is effective in a technical field using a multicolor molded product and a multicolor molding method in which a plurality of different resins are combined and integrated, and a technical field for manufacturing the same.

    DESCRIPTION OF SYMBOLS 1 ... Optical element (1st shaping | molding part), 2 ... Coloring outer peripheral part (2nd shaping | molding part), 3 ... Intermediate | middle layer (3rd shaping | molding part), 5 ... 1st hot-melt coupling part, 6 ... 2nd heat | fever Melt joint.

Claims (4)

A first molding part formed by injection molding a first molding resin;
A second molded part formed by injection molding a second molded resin that is arranged apart from the first molded part and is different from the first molded resin;
A third molding resin, which is disposed between the first molding part and the second molding part and is different from the first molding resin and the second molding resin, is formed between the first molding part and the second molding part. A third molded part formed by injection molding between,
A hot melt joint portion joined in a state of being melted and mixed at the joint interface between the first molding portion and the third molding portion and the joint interface between the third molding portion and the second molding portion, respectively. Multicolor molded product provided. The multicolor molded article according to claim 1,
The third molding resin is a multicolor molded product having a resin characteristic that is bonded to the resin characteristics of the first molding resin and the second molding resin. The multicolor molded product according to claim 2,
The first molding part forms an optical element, the second molding part forms a frame around the optical element, and the third molding part forms an intermediate layer disposed between the optical element and the frame part. Multicolor molded products. A first molding step of forming a first molding part by injection molding a first molding resin;
A second molding step that is arranged apart from the first molding part and injection-molds a second molding resin different from the first molding resin to form a second molding part;
A third molding resin different from the first molding resin and the second molding resin is injection-molded between the first molding portion and the second molding portion, and the first molding portion and the second molding portion A third molding step for forming a third molding portion disposed between
Have
The first molding step, the second molding step, and the third molding step are performed in the order of low melting temperatures of the first molding resin, the second molding resin, and the third molding resin. Molding method for multicolor molded products.

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