JP2007276396A - Molding method of resin lens and resin lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding method of a resin lens and a resin lens capable of shortening molding time or the like. <P>SOLUTION: A molding method of a resin lens comprises the primary molding step for forming a primary molded product 400 having at least a projection part 3 byinjection molding of a thermoplastic resin 300, and the secondary molding step for forming a secondary molded product 700 having a plane part by laminating the thermoplastic resin 500 or a photo-curable resin 600 on the surface of the opposite side to the projecting direction from the plane part 2 of the projection part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a resin lens molding method and a resin lens. More specifically, the present invention relates to a technical field in which a thermosetting resin or a photocurable resin is laminated on a primary molded product formed of a thermoplastic resin to shorten the molding time.

  As a lens of a vehicle lamp, for example, there is a projector lens used for a headlamp. The projector lens includes a flat portion and a protrusion that protrudes from the flat portion and has an outer surface formed as an aspheric surface.

  Since such a projector lens is thick in the optical axis direction, if it is molded by injection molding using a molten resin, a large sink is formed on the flat surface side during cooling after injection of the molten resin, and the molding accuracy is likely to deteriorate. There is a problem.

  Therefore, as a conventional molding method, first, a major part on the protruding side is formed by injection molding to form a primary molded product, and the same molten resin is injected into the sink portion generated in the primary molded product to obtain a flat surface. There is a method of forming a secondary molded product by forming a portion (see, for example, Patent Document 1).

JP 2000-113701 A

  However, in the above-described conventional molding method, the molten resin is injected into the mold and cooled, and again, the molten resin is injected into the mold to cool down. The time is increased and productivity is reduced.

  In addition, different molds for injection molding are required for the process of molding the primary molded product and the process of molding the secondary molded product, but injection molding requires large-scale equipment and the mold is expensive. Therefore, there is a problem that the manufacturing cost increases.

  Therefore, an object of the molding method and the resin lens of the present invention is to shorten the molding time.

  In order to solve the above-described problems, the resin lens molding method of the present invention includes a primary molding step of forming a primary molded product having at least a protrusion by injection molding of a thermoplastic resin, and a protruding direction from the flat portion of the protrusion. And a secondary molding step of forming a secondary molded product having a flat portion by laminating a thermosetting resin or a photocurable resin on the opposite surface.

  In order to solve the above-described problems, the resin lens of the present invention is formed on a surface opposite to the protruding direction from the flat portion of the protruding portion in the primary molded product having at least the protruding portion formed by injection molding of a thermoplastic resin. It is formed by laminating a curable resin or a photocurable resin.

  Therefore, in the resin lens molding method and resin lens of the present invention, the resin is heated or irradiated with light in the secondary molding step.

  The resin lens molding method of the present invention is a resin lens molding method comprising a flat portion and a protrusion protruding from the flat portion, and a primary molded product having at least a protrusion is formed by injection molding of a thermoplastic resin. A primary molding step, and a secondary molding step of forming a secondary molded product having a planar portion by laminating a thermosetting resin or a photocurable resin on a surface opposite to the protruding direction from the planar portion of the protrusion. It is characterized by comprising.

  Therefore, the molding time is shortened and productivity can be improved as compared with the case where both primary molding and secondary molding are performed by injection molding.

  In the invention described in claim 2, in the primary molding step, the first molding die that forms the protruding portion side and the second molding die that forms the flat portion side are used. Since the molding die is made of a material having higher thermal conductivity than the second molding die, sink marks are unlikely to occur on the projection side, and the processing accuracy of the projection of the resin lens can be improved. .

  In the invention described in claim 3, since the light curable resin is solidified by irradiating light from the protrusion side in the secondary molding step, the light irradiation to the photo curable resin is simple and reliable. Can be done.

  The resin lens of the present invention is a resin lens comprising a flat portion and a protrusion protruding from the flat portion, and is a flat surface of the protrusion in a primary molded product having at least a protrusion formed by injection molding of a thermoplastic resin. It is characterized by being formed by laminating a thermosetting resin or a photocurable resin on the surface opposite to the protruding direction from the portion.

  Therefore, the molding time is shortened and productivity can be improved as compared with the case where both primary molding and secondary molding are performed by injection molding.

  The best mode for carrying out the resin lens molding method and the resin lens of the present invention will be described below with reference to the accompanying drawings.

  The resin lens 1 is used, for example, as a projector lens of a vehicle headlamp 1000, and is attached to the front end portion of the lamp housing 1001 (see FIG. 1). A light source 102 is attached to a rear end portion of the lamp housing 1001, and a shade 1003 for controlling light emitted from the light source 1002 is disposed in front of the light source 1002.

  The resin lens 1 is formed by integrally forming a flat portion 2 formed in a disc shape facing in the front-rear direction and a protrusion 3 protruding forward from the flat portion 2 (see FIG. 1). The surface of the protrusion 3 is aspherical.

  The resin lens 1 is mostly formed of a thermoplastic resin, for example, an acrylic resin having a refractive index of 1.4 to 1.7, and a part thereof is a thermosetting resin having a refractive index equivalent to that of the thermoplastic resin. Or it is formed with the photocurable resin.

  Hereinafter, a method for molding the resin lens 1 will be described (see FIGS. 2 to 5).

  First, the first molding die 101 and the second molding die 102 are used as the injection molding die 100, and the thermoplastic resin (molten resin) 300 is filled in the cavity 103 formed by both (see FIG. 2). The first molding die 101 is formed of, for example, an aluminum alloy or a copper alloy, and the second molding die 102 is formed of, for example, a high heat resistant resin. Is set to be higher than the thermal conductivity of the second molding die 102. The thermoplastic resin 300 is, for example, an acrylic resin.

  Next, the thermoplastic resin 300 filled in the cavity 103 is cooled and solidified to form a primary molded product 400 (see FIG. 3). In the state where the thermoplastic resin 300 is cooled and the primary molded product 400 is formed, sink marks occur. Sinks are likely to occur on the flat surface side of the primary molded product 400, and the recesses 400a are formed by the sinks.

  At this time, as described above, since the first molding die 101 is made of a material having a higher thermal conductivity than the second molding die 102, the thermal conductivity from the thermoplastic resin 300 is high. The first molding die 101 is higher than the second molding die 102, and sink marks are less likely to occur on the projecting side of the primary molded product 400, and sink marks are likely to occur on the flat surface side. Therefore, the processing accuracy of the protrusion 3 of the resin lens 1 can be improved.

  Even when the first molding die 101 is not formed of a material having a higher thermal conductivity than the second molding die 102, for example, the first molding die 101 is used as the second molding die. Using a so-called core back that is slightly separated from the mold 102 to form a minute gap therebetween to reduce the amount of heat transferred to the second molding mold 102 side of the primary molded product 400, primary molding is performed. It is also possible to form a recess 400 a by causing a sink on the flat side of the product 400.

  Next, the primary molded product 400 is taken out from the injection mold 100 and the primary molded product 400 is mounted on the secondary mold 200.

  The secondary molding die 200 includes a mounting die 201 and a molding die 202, and a light irradiation hole 201a is formed at the center of the mounting die 201 (see FIG. 4).

  The primary molded product 400 is mounted on the mounting mold 201, the molding mold 202 is coupled to the mounting mold 201, for example, from above, and the thermosetting resin 500 or the photocurable resin is formed in the recess 400a formed by sink marks. Fill 600.

  Next, when the thermosetting resin 500 is filled in the state where the concave portion 400a of the primary molded product 400 is filled with the thermosetting resin 500 or the photocurable resin 600, heat s, s, When the thermosetting resin 500 is solidified and filled with the photocurable resin 600, the primary molded product 400 is transmitted through the light irradiation hole 201a and light p is applied to the photocurable resin 600. , P,..., And photocurable resin 600 is solidified. As described above, by irradiating the photocurable resin 600 with the light p, p,... Through the light irradiation hole 201a, the photocurable resin 600 can be easily and reliably irradiated with light. .

  In the case of filling the photocurable resin 600, the molding die 202 is formed of a material that transmits light, such as glass, and the light is irradiated from the upper side to the lower side to transmit the molding die 202. It is also possible to solidify the photocurable resin 600. In this case, the time required for solidifying the photocurable resin 600 can be shortened by forming the molding die 200 with a material higher than the light transmittance of the primary molded product 400.

  By solidifying the thermosetting resin 500 or the photocurable resin 600, these are combined with the primary molded product 400 in a laminated manner to form the flat portion 2, and the secondary molded product 700 is formed to form the resin lens 1. Molded (see FIG. 5).

  Finally, the resin lens 1 is taken out from the secondary molding die 200.

  As described above, the resin lens 1 includes the primary molding step of forming the primary molded product 400 by injection molding of the thermoplastic resin 300, and the thermosetting resin or the photocurable resin laminated on the primary molded product 400. Since it is molded by the secondary molding process for forming the next molded product 700, the molding time can be shortened and productivity can be improved as compared with the case where both primary molding and secondary molding are performed by injection molding. it can.

  In order to reduce the occurrence of sink marks, it is necessary to cool at a slow speed. However, in the resin lens 1, since it is not necessary to prevent the occurrence of sink marks, the cooling time is set at a slow speed. There is no need to perform this, and the molding time can be shortened by shortening the cooling time.

  Further, when both the primary molding step and the secondary molding step are performed by injection molding by cooling a molten resin, there is a possibility that sink marks may occur in the secondary molded product. Since the thermosetting resin 500 or the photocurable resin 600 is solidified in the molding step, sink marks are unlikely to occur, and the processing accuracy of the resin lens 1 can be improved.

  In addition, an expensive injection mold is not required for both the primary molding process and the secondary molding process, and the manufacturing cost can be reduced.

  In addition, although the resin lens 1 which formed the plane part 2 in the smooth surface was shown above as an example, for example, fine unevenness such as a texture pattern on the plane part 2A using a thermosetting resin or a photocurable resin. It is also possible to mold the resin lens 1A formed with (see FIGS. 6 and 7) as follows.

  The molding die 202A of the secondary molding die 200A has an uneven portion 202a for forming a texture pattern or the like on the lower surface thereof.

  When the thermosetting resin 500 or the photocurable resin 600 is filled in the concave portion 400a of the primary molded product 400 and the thermosetting resin 500 is filled as shown in FIG. 6, the molding die 202A is heated. When the thermosetting resin 500 is solidified by adding s, s,... and filled with the photocurable resin 600, the primary molded product 400 is transmitted through the light irradiation hole 201a to the photocurable resin 600. On the other hand, light p, p,... Is irradiated to solidify the photocurable resin 600.

  By solidifying the thermosetting resin 500 or the photocurable resin 600, these are combined with the primary molded product 400 in a laminated form to form a planar portion 2A having irregularities 2a such as a textured pattern, and the secondary molded product 700A. Is formed to mold the resin lens 1A (see FIG. 7).

  Thus, by forming the resin lens 1A having the unevenness 2a such as the embossed pattern using the thermosetting resin 500 or the photocurable resin 600, the unevenness 2a such as the embossed pattern can be easily formed.

  Moreover, in order to form the resin lens 1A having the unevenness 2a such as a texture pattern, an expensive injection molding die is not required for both the primary molding process and the secondary molding process, and the manufacturing cost is reduced and produced. It is possible to improve the performance.

  6 and 7 show an example in which the concave portion 400a caused by the sink is filled with the thermosetting resin 500 or the photocurable resin 600, but there is no sink on the flat portion side of the primary molded product. Even in this case, the resin lens 1A having the unevenness 2a such as a texture pattern can be formed by the same method as described above.

  The shapes and structures of the respective parts shown in the above-described best mode are merely examples of implementations in carrying out the present invention, and the technical scope of the present invention is limitedly interpreted by these. It should not be done.

FIG. 2 to FIG. 7 show the best mode of the present invention, and this figure is a sectional view showing an example of a vehicle headlamp provided with a resin lens. FIGS. 3 to 5 show a resin lens molding process, and this figure is a cross-sectional view showing a state in which a thermoplastic resin is filled in an injection mold. It is sectional drawing which shows the state by which the filled thermoplastic resin was solidified and the primary molded article was formed. It is sectional drawing which shows the state with which the thermosetting resin or the photocurable resin was filled. It is sectional drawing which shows the state by which the filled thermosetting resin or photocurable resin was solidified, the secondary molded product was formed, and the resin lens was shape | molded. FIG. 7 shows a molding process of a resin lens having projections and depressions together with FIG. It is sectional drawing which shows the state by which the filled thermosetting resin or photocurable resin was solidified, the secondary molded product was formed, and the resin lens was shape | molded.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Resin lens, 2 ... Plane part, 3 ... Projection part, 101 ... 1st molding die, 102 ... 2nd molding die, 300 ... Thermoplastic resin, 400 ... Primary molding product, 500 ... Heat Curable resin, 600 ... Photocurable resin, 700 ... Secondary molded product, 1A ... Resin lens, 2A ... Plane, 700A ... Secondary molded product

Claims (4)

A method of molding a resin lens comprising a flat portion and a protrusion protruding from the flat portion,
A primary molding step of forming a primary molded article having at least a protrusion by injection molding of a thermoplastic resin;
A secondary molding step of laminating a thermosetting resin or a photocurable resin on a surface opposite to the projecting direction from the planar portion of the projecting portion to form a secondary molded product having the planar portion. Resin lens molding method. In the primary molding step, using a first molding die that forms the protruding portion side and a second molding die that forms the flat portion side,
The method for molding a resin lens according to claim 1, wherein the first molding die is formed of a material having higher thermal conductivity than the second molding die. 3. The method for molding a resin lens according to claim 1, wherein in the secondary molding step, light is radiated from a protrusion side to solidify the photocurable resin. 4. A resin lens comprising a flat portion and a protrusion protruding from the flat portion,
In a primary molded product having at least a protrusion formed by injection molding of a thermoplastic resin, a thermosetting resin or a photocurable resin is laminated on the surface opposite to the protruding direction from the flat surface of the protrusion. Resin lens characterized by.

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