EP-4032676-B1 - METHOD FOR PRODUCING OPTICAL MEMBER AND OPTICAL MEMBER

Inventors

• ITO, SHINSUKE
• Ribeiro, Nigel

Dates

Publication Date

20260506

Application Date

20200916

Claims (8)

1. A method of manufacturing an optical member by curing a thermally polymerizable composition by heating, comprising, in the following order: a first step of filling an inside of a mold with the thermally polymerizable composition in which the mold is configured by disposing a frame-shaped member, with a Young's modulus of 1.0 GPa or more at a polymerization initiation temperature T (°C) of the thermally polymerizable composition, between two mold members facing each other; and a second step of heating the mold to the polymerization initiation temperature T or more, wherein the thermally polymerizable composition contains at least one selected from the group consisting of a poly(thi)ol compound, a polyiso(thio)cyanate compound and an episulfide compound, and wherein the method comprises removing the two mold members and the frame-shaped member after the second step to provide the optical member.
2. The method of manufacturing an optical member according to claim 1, wherein: the frame-shaped member is provided with at least one aperture, and in the first step, the thermally polymerizable composition is filled inside the mold from the aperture.
3. The method of manufacturing an optical member according to claim 2, wherein: the frame-shaped member is provided with a plurality of apertures, and a frame portion of the frame-shaped member is positioned on virtual straight lines extending from an outside of the apertures to an inside of the frame-shaped member via the apertures.
4. The method of manufacturing an optical member according to claim 2 or 3, wherein in the first step, when the mold is disposed such that main surfaces of the mold member is substantially orthogonal to a vertical direction, the mold is provided with an aperture member connecting with the aperture at an outer peripheral side of the frame-shaped member and sloping toward a vertical upper side, and the thermally polymerizable composition is filled inside the mold via the aperture member.
5. The method of manufacturing an optical member according to any one of claims 1 to 4, wherein the mold is a mold layered body configured by stacking the mold members and frame-shaped members repeatedly.
6. The method of manufacturing an optical member according to claim 5, wherein, in the second step, the mold layered body is disposed such that main surfaces of the mold members are substantially orthogonal to a vertical direction and the mold layered body is heated.
7. The method of manufacturing an optical member according to any one of claims 1 to 6, wherein an average distance between main surfaces of the two mold members facing each other in the mold is 10 mm or less.
8. The method of manufacturing an optical member according to any one of claims 1 to 7, wherein a refractive index of the optical member is 1.58 or more.

Description

Technical Field The present disclosure relates to a method of manufacturing an optical member, and an optical member. Background Art As a method of manufacturing a plastic lens, a casting polymerization method has been known. In this method, a pair of glass molds are disposed at predetermined intervals, and an adhesive tape is attached to the outer peripheral surfaces of these glass molds along the circumferential direction to seal the space between the pair of glass molds. Next, the injection nozzle is inserted into the sealed space, and the polymerizable monomer is injected and filled into the space via the injection nozzle. Then, the polymerizable monomer polymerizes and is cured by heating or the like to obtain a plastic lens molded product. Various techniques have been proposed as an adhesive tape used in manufacturing this plastic lens molded product (see, for example, Patent Literature 1 and 2). Patent Literature 3 and 4 also disclose methods of manufacturing optical members. Patent Literature 3 discloses curing a thermally polymerizable composition. [Prior Art Document] [Patent Literature] [Patent Literature 1] Japanese Patent Application Laid-Open (JP-A) No. 2012-915[Patent Literature 2] JP-A No. 2012-17363[Patent Literature 3] JP S62 212108[Patent Literature 4] JP 2001 167473 SUMMARY OF INVENTION Technical Problem In the method of molding the plastic lens described in Patent Literature 1 and Patent Literature 2, as the polymerization shrinks, the adhesive tape deforms and follows the shrinkage. However, in the method of molding the plastic lens used in these adhesive tape, the deformation of the adhesive tape cannot be adjusted, and thereby it was difficult to adjust, an absolute value (hereinafter, also referred to as "parallelism of main surfaces") of the difference in flatness between two main surfaces of the plastic lens to be manufactured, to be small. Further, in the case of manufacturing a blank for the plastic lens as in the techniques described in Patent Literature 1 and Patent Literature 2, after the blank is manufactured, the blank is polished to be processed into a prescription lens (processing for prescription lens corresponding to lowering parallelism between the main surfaces), and therefore, there was no technical challenge to increase parallelism of the blank main surfaces. However, the inventors of the present disclosure paid attention to the fact that the accuracy of optical information transmission is improved by using an optical member having high parallelism of the main surfaces for the apparatus for transmitting optical information described later, and they have found a challenge of manufacturing an optical member excellent in parallelism of main surfaces. An object of the present disclosure is to provide an optical member capable of manufacturing an optical member excellent in parallelism of main surfaces, and an optical member excellent in parallelism of the main surfaces. Solution to Problem The present disclosure relates to the following aspects. <1> A method of manufacturing an optical member by curing a thermally polymerizable composition by heating, comprising, in the following order: a first step of filling an inside of a mold with the thermally polymerizable composition in which the mold is configured by disposing a frame-shaped member, with a Young's modulus of 1.0 GPa or more at a polymerization initiation temperature T (°C) of the thermally polymerizable composition, between two mold members facing each other; and a second step of heating the mold to the polymerization initiation temperature T or more.<2> The method of manufacturing an optical member according to <1>, wherein: the frame-shaped member is provided with at least one aperture, and in the first step, the thermally polymerizable composition is filled inside the mold from the aperture.<3> The method of manufacturing an optical member according to <2>, wherein: the frame-shaped member is provided with a plurality of apertures, and a frame portion of the frame-shaped member is positioned on virtual straight lines extending from an outside of the apertures to an inside of the frame-shaped member via the apertures.<4> The method of manufacturing an optical member according to <2> or <3>, wherein in the first step, when the mold is disposed such that main surfaces of the mold member is substantially orthogonal to a vertical direction, the mold is provided with an aperture member connecting with the aperture at an outer peripheral side of the frame-shaped member and sloping toward a vertical upper side, and the thermally polymerizable composition is filled inside the mold via the aperture member.<5> The method of manufacturing an optical member according to any one of <1> to <4>, wherein the mold is a mold layered body configured by stacking the mold members and frame-shaped members repeatedly.<6> The method of manufacturing an optical member according to <5>, wherein, in the second step, the mold layered bod