Method for manufacturing optical components

Abstract

To obtain optical components with suppressed surface roughness and flow marks.SOLUTION: In a process for injecting a molten resin composition through a gate section 38 and filling a cavity 36 using a screw 24, a method for manufacturing an optical component, the following (Condition 1) and (Condition 2) are satisfied. (Condition 1) The ratio b / a of the injection rate a which is obtained by the following formula (1) when the tip of the molten resin composition passes from the entrance to the exit of the above gate section 38, and the injection rate b after the tip of the molten resin composition passes through the exit of the above gate section 38 obtained by the following formula (2), is 3 to 16 or less. (Condition 2) The above injection rate b is between 45 cm3 / sec and 100 cm3 / sec. a=σ×va(1), b=σ×vb(2) σ: Cross-sectional area inside cylinder 22 va, vb: Forward speed of screw under specified conditions.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing an optical component and to an optical component. [Background technology]

[0002] Because cyclic olefin copolymers have excellent optical properties, they are used, for example, as optical components such as optical lenses. Examples of technologies related to the manufacturing of optical components made of cyclic olefin copolymers are described in Patent Documents 1 to 3.

[0003] Patent Document 1 discloses a method for manufacturing a cyclic olefin resin molded article, characterized by molding a cyclic olefin resin consisting of a cyclic olefin polymer of a specific structure using a molding machine that employs a screw and cylinder in which the dimensional difference (Dd) between the screw diameter (d) and the cylinder inner diameter (D) is 0.2 mm or more, and the screw compression ratio is 1.6 to 2.4. It is stated that this manufacturing method suppresses the occurrence of black spots in the resin molded article and provides excellent product yield during continuous operation. However, Patent Document 1 does not describe the injection rate.

[0004] Patent Document 2 describes a cyclic polyolefin thermoplastic resin, with a resin temperature of (Tg+100)°C to 400°C (where Tg represents the glass transition temperature of the thermoplastic resin; the same applies hereafter), a mold temperature of (Tg-100)°C to (Tg-5)°C, and a shear rate of 4 × 10⁻⁶ 4 ~1 × 10 6 A method for manufacturing an optical recording medium is disclosed, characterized by injection molding the thermoplastic resin at a rate of / second and an average residence time of 5 to 200 seconds in the molding machine. It is stated that this manufacturing method suppresses the occurrence of silver streaks and provides excellent transferability. However, Patent Document 2 does not describe changing the injection rate of the resin composition depending on the location in the molding machine.

[0005] Patent Document 3 describes a method for manufacturing an optical member using an injection molding apparatus comprising: an injection unit consisting of a cylinder and a screw inserted into the cylinder; a cavity for molding an optical member having an optical surface; and a mold having a gate that serves as an injection outlet for a molten resin composition from the injection unit into the cavity, comprising the steps of: melting a resin composition containing ethylene or an α-olefin and a cyclic olefin in the cylinder; and injecting the molten resin composition through the gate using the screw and filling the cavity, wherein the injection rate a(cm) of the resin composition as it passes through the gate. 3 b(cm) of the injection rate of the resin composition in the cavity relative to ( / second) 3 A method for manufacturing an optical component is disclosed, in which the ratio b / a (indicated by the number of seconds) is 1.5 to 6.5. It is stated that this manufacturing method suppresses surface roughness of the optical surface and provides excellent surface smoothness. However, Patent Document 3 does not specify a concrete numerical range for the ejection ratio. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2000-233425 [Patent Document 2] Japanese Patent Publication No. 2001-121569 [Patent Document 3] Japanese Patent Publication No. 2022-65314 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, the manufacturing methods described in Patent Documents 1 to 3 had room for improvement in the appearance of the resulting resin molded products. [Means for solving the problem]

[0008] As a result of investigations, the inventors of the present invention have found that by adjusting the injection rate of the resin composition in the gate section within the injection molding apparatus, the occurrence of surface roughness and flow marks can be suppressed, and thus the present invention has been completed. That is, the present invention can be described as follows.

[0009] [1] An injection molding apparatus comprising an injection unit consisting of a cylinder and a screw inserted into the cylinder, a mold having a cavity for molding an optical member and a gate section serving as an injection passage for the resin composition from the injection unit into the cavity, A method for manufacturing an optical member using the injection molding apparatus, comprising: Step (1) of melting a resin composition containing a copolymer of ethylene or an α-olefin and a cyclic olefin in the cylinder; Step (2) of injecting the melted resin composition through the gate section using the screw and filling the cavity, In step (2), a method for manufacturing an optical member that satisfies the following (Condition 1) and (Condition 2). (Condition 1) The ratio b / a of the injection rate b of the tip of the melted resin composition, obtained by the following formula (2), to the injection rate a when the tip of the melted resin composition passes from the entrance to the exit of the gate section, obtained by the following formula (1), is 3 or more and 16 or less. (Condition 2) The injection rate b is 45 cm 3 / second or more and 100 cm 3 / second or less. a = σ × v a (1) b = σ × v b (2) σ: Cross-sectional area inside the cylinder of the injection molding apparatus v a : Forward speed of the screw when the tip of the melted resin composition passes from the entrance to the exit of the gate section v b: The forward speed of the screw after the tip of the molten resin composition has passed the exit of the gate section. [2] The method for manufacturing an optical member according to [1], wherein the b / a is 7 or more and 16 or less. [3] A method for manufacturing an optical member according to [1] or [2], wherein the following conditions (3) and (4) are further satisfied in step (2). (Condition 3) The ratio x / a of the injection rate x of the molten resin composition before the leading edge passes through the entrance of the gate section, as calculated by the following formula (3), to the injection rate a is 1 or more and 6 or less. (Condition 4) The injection rate x is 6 cm 3 / second or more 30cm 3 It is less than / second. x = σ × v x (3) σ: Cross-sectional area inside the cylinder of the injection molding apparatus. v x : The forward speed of the screw before the tip of the molten resin composition passes through the entrance of the gate section. [4] A method for manufacturing an optical member according to any one of [1] to [3], wherein in step (2), the shear rate γ determined by the following formula (4) is 300 / second or more. γ = πDN / h (4) D: Screw diameter N: Screw rotation speed h: Screw groove depth [5] The cavity volume of the aforementioned mold is 5 cm³ 3 More than 150cm 3 A method for manufacturing an optical member as described in any of the above [1] to [4]. [6] The copolymer, A repeating unit (a) derived from at least one olefin represented by the following general formula (I), A repeating unit (b) derived from a cyclic olefin, selected from the group consisting of repeating units represented by the following general formula (II), repeating units represented by the following general formula (III), repeating units represented by the following general formula (IV), repeating units represented by the following general formula (V), and repeating units represented by the following general formula (VI), A method for manufacturing an optical member according to any one of the above [1] to [5], comprising: [ka] In the above general formula (I), R 300 This represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms. [ka] In the general formula (II) above, u is 0 or 1, v is 0 or a positive integer, w is 0 or 1, and R 61 ~R 78 Furthermore, R a1 and R b1 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R 75 ~R 78 These elements may be bonded to each other to form a monocycle or polycycle. [ka] In the above general formula (III), x and d are integers of 0 or greater than or equal to 1, y and z are 0, 1 or 2, and R 81 ~R 99 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group which is 6 to 20 carbon atoms or an alkoxy group, and R 89 and R 90 The carbon atom to which it is bonded, and R 93The carbon atom or R to which it is bonded 91 The carbon atom to which it is bonded may be directly bonded or bonded via an alkylene group having 1 to 3 carbon atoms, and when y=z=0, R 95 and R 92 or R 95 and R 99 These elements may be bonded to each other to form a monocyclic or polycyclic aromatic ring. [ka] In the above general formula (IV), n and m are each independently 0, 1, or 2, q is 1, 2, or 3, and R 18 ~R 31 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and when q=1, R 28 and R 29 , R 29 and R 30 , R 30 and R 31 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 28 and R 28 , R 28 and R 29 , R 29 and R 30 , R 30 and R 31 , R 31 and R 31 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may be an aromatic ring. [ka] In the above general formula (V), R 100 , R 101 These elements may be identical or different from each other, and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, where f is an integer between 1 and 18. [ka] In the above general formula (VI), q is 1, 2, or 3, and R32 ~R 39 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and when q=1, R 36 and R 37 , R 37 and R 38 , R 38 and R 39 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 36 and R 36 , R 36 and R 37 , R 37 and R 38 , R 38 and R 39 , R 39 and R 39 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may have a double bond, and the monocycle or polycycle may be an aromatic ring. [7] The repeating unit (b) derived from the cyclic olefin in the copolymer is bicyclo[2.2.1]-2-heptene, tetracyclo[4.4.0.1 2,5 .1 7,10 A method for producing an optical component according to [6], comprising a repeating unit derived from at least one compound selected from the group consisting of ]-3-dodecene and benzonorbornadiene. [8] A method for producing an optical member according to [6] or [7], wherein the repeating unit (a) derived from the olefin in the copolymer includes a repeating unit derived from ethylene. [9] An optical component manufactured by the method for manufacturing an optical component described in any of the above [1] to [8]. [Effects of the Invention]

[0010] According to the method for manufacturing optical components of the present invention, it is possible to obtain optical components in which surface roughness and flow marks are suppressed. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic cross-sectional view of a mold for an injection molding machine. [Figure 2] This figure shows an optical microscope image of the lens surface (optically effective surface) obtained in Example 5. [Figure 3] This figure shows an optical microscope image of the lens surface (optically effective surface) obtained in Example 2. [Figure 4] This figure shows an optical microscope image of the lens surface (optically effective surface) obtained in Comparative Example 7. [Figure 5] This figure shows an optical microscope image illustrating the surface roughness that occurred on the lens surface (optically effective surface) obtained in Comparative Example 4. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described below.

[0013] [Method for manufacturing optical components] The method for manufacturing an optical component according to this embodiment is: An injection unit comprising a cylinder and a screw inserted into the cylinder, A mold having a cavity for molding an optical component, and a gate section that serves as an injection passage for a resin composition from the injection unit into the cavity, A method for manufacturing an optical component using an injection molding apparatus, comprising: (1) A step of melting a resin composition containing ethylene or an α-olefin and a cyclic olefin in the cylinder, The process includes (2) using the screw to inject the molten resin composition through the gate section and fill the cavity, In step (2) above, the following (Condition 1) and (Condition 2) are satisfied. (Condition 1) The ratio b / a of the injection rate b after the tip of the molten resin composition has passed the exit of the gate section, calculated by formula (2) below, to the injection rate a when the tip of the molten resin composition has passed the exit of the gate section, calculated by formula (1) below, is 3 or more and 16 or less. (Condition 2) The injection rate b is 45 cm 3 / second or more 100cm 3 It is less than / second. a = σ × v a (1) b = σ × v b (2) σ: Cross-sectional area inside the cylinder of the injection molding apparatus. v a : The forward speed of the screw as the tip of the molten resin composition passes from the entrance to the exit of the gate section. v b : The forward speed of the screw after the tip of the molten resin composition has passed the exit of the gate section.

[0014] According to the manufacturing method of this embodiment, an optical component can be obtained in which surface roughness and flow marks are suppressed.

[0015] Here, flow marks refer to a type of surface defect in injection molding, where traces of molten resin flow remain on the surface of a resin product. Flow marks are generally said to occur when the flow of resin within the injection molding machine is obstructed. The inventors focused on the flow of resin in the gate section, which is one of the sections in an injection molding machine where the width between the first mold 32 and the second mold 34 is narrowest, and where the resin flow path is narrowest. They discovered that the occurrence of flow marks can be suppressed by adjusting the values ​​of b / a and b, and thus completed the present invention.

[0016] The injection molding apparatus used in the manufacturing method according to this embodiment, each step of the manufacturing method according to this embodiment, and the raw materials used in the manufacturing method according to this embodiment will be described below.

[0017] <Injection molding equipment> As shown in Figure 1, the injection molding apparatus 10 of this embodiment comprises an injection unit 20 and a mold 30.

[0018] The injection unit 20 consists of a cylinder 22 and a screw 24 inserted into the cylinder 22, and is connected to a hopper 26 into which the resin composition is fed. The resin composition fed from the hopper 26 is heated and melted in the cylinder 22, and the screw 24 transports the molten resin composition forward and injects it into the cavity 36 by piston motion. The injection rate of the molten resin can be changed by the forward speed of the screw 24.

[0019] Furthermore, the preferred numerical range for the diameters of the cylinder 22, screw 24, nozzle, etc., is not particularly limited, as it varies appropriately depending on the specifications of the injection molding apparatus and the size of the molded product. The mold 30 consists of a first mold 32 and a second mold 34, and a cavity 36 for molding an optical member having an optical surface is provided between these molds.

[0020] The cavity 36 is connected to a gate section 38, which serves as an injection passage for injecting molten resin from the injection unit 20 into the cavity 36. The gate section 38 is in communication with the runner 40 and the sprue 44, and is configured to allow molten resin injected from the injection unit 20 to be injected and filled into the cavity 36.

[0021] The flow path of the resin composition in the gate section 38 is narrower compared to the flow paths of the resin composition in other sections such as the runner 40 and sprue 44. In other words, the gate section 38 can be said to be one of the sections in the injection molding apparatus where the flow path of the resin composition is narrowest. Specifically, the width between the first mold 32 and the second mold 34 in the gate section 38, that is, the width of the gate section 38 when viewed from the direction shown in Figure 1, is approximately 20% to 99% of the width between the first mold 32 and the second mold 34 in the runner 40. Furthermore, the width of the first mold 32 (second mold 34) in the gate section 38, that is, the width of the gate section 38 when viewed from a direction perpendicular to the direction in Figure 1 (the direction in which the lens surface is viewed from the front), is approximately 20% to 99% of the width of the first mold 32 (second mold 34) in the runner 40. In this embodiment, the width of each section of the injection molding apparatus refers to the width of the widest point within each section. The inventors focused on the gate section 38, which is one of the narrowest sections in the resin flow path, and discovered that the occurrence of flow marks can be suppressed by adjusting the resin flow in this section, thus completing the present invention.

[0022] The width between the first mold 32 and the second mold 34 in the gate section 38 is, for example, 0.1 mm or more, preferably 0.5 mm or more, more preferably 0.8 mm or more, even more preferably 1.0 mm or more, even more preferably 1.2 mm or more, and for example, 10 mm or less, preferably 8 mm or less, more preferably 5 mm or less, and even more preferably 2 mm or less.

[0023] Furthermore, the width of the first mold 32 (second mold 34) in the gate section 38 is, for example, 1 mm or more, preferably 2 mm or more, more preferably 5 mm or more, even more preferably 8 mm or more, and for example, 100 mm or less, preferably 80 mm or less, more preferably 50 mm or less, even more preferably 20 mm or less, and even more preferably 15 mm or less.

[0024] The cross-sectional shape of the gate section 38 can be any shape, such as a circle, ellipse, or polygon.

[0025] The width between the first mold 32 and the second mold 34 in the runner section 40 is, for example, 0.5 mm or more, preferably 1.0 mm or more, more preferably 2.0 mm or more, even more preferably 3.0 mm or more, even more preferably 5.0 mm or more, and, for example, 50 mm or less, preferably 30 mm or less, more preferably 20 mm or less, even more preferably 10 mm or less, and even more preferably 8 mm or less.

[0026] Furthermore, the width of the runner section 40 first mold 32 (second mold 34) is, for example, 0.5 mm or more, preferably 1.0 mm or more, more preferably 2.0 mm or more, even more preferably 3.0 mm or more, even more preferably 5.0 mm or more, and, for example, 50 mm or less, preferably 30 mm or less, more preferably 20 mm or less, even more preferably 10 mm or less, and even more preferably 8 mm or less.

[0027] The cross-sectional shape of the runner section 40 can be any shape, such as a circle, ellipse, or polygon.

[0028] The cavity 36 is a region for forming the desired optical component, and the optical component has a cross-sectional shape such as a convex-concave shape on one side, a convex shape on both sides, a concave shape on both sides, a flat-concave shape on one side, a flat-convex shape on one side, or a flat-flat-flat shape on one side. The optical component may also have a circular or elliptical shape in plan view.

[0029] The width a between the first mold 32 and the second mold 34 in the cavity 36 is, for example, 2 mm or more, preferably 2.5 mm or more, and can be, for example, 15 mm or less, preferably 12 mm or less, and more preferably 10 mm or less. If the cross-sectional shape of the cavity 36 is convex or concave, the width a is defined as the width at the point where the distance between the first mold 32 and the second mold 34 is greatest.

[0030] The first mold 32 exposes a molding surface 32a for forming the optical surface of the optical member within the cavity 36. The shape of the molding surface 32a is set according to the shape of the optical surface of the optical member, and may be convex, concave, or flat in cross-sectional shape, and may be circular, elliptical, etc. in plan view. The width (diameter in the case of a circular shape) of the molding surface 32a is indicated by b in FIG. 1.

[0031] The area of the molding surface 32a is, for example, 310 mm 2 or more, preferably 415 mm 2 or more, more preferably 490 mm 2 or more, and, for example, 2850 mm 2 or less, preferably 2000 mm 2 or less. When the molding surface 32a is circular in plan view, the diameter b can be, for example, 20 mm or more, preferably 23 mm or more, more preferably 25 mm or more, and, for example, 80 mm or less, preferably 60 mm or less, more preferably 50 mm or less.

[0032] The second mold 34 exposes a molding surface 34a for forming the optical surface of the optical member within the cavity 36. The shape of the molding surface 34a is set according to the shape of the optical surface of the optical member, and may be convex, concave, or flat in cross-sectional shape, and may be circular, elliptical, etc. in plan view. The width (diameter in the case of a circular shape) of the molding surface 34a is indicated by c in FIG. 1.

[0033] The area of the molding surface 34a is, for example, 310 mm 2 or more, preferably 415 mm 2 or more, more preferably 490 mm 2 or more, and, for example, 5030 mm 2 or less, preferably 2850 mm 2 or less, more preferably 2000 mm 2The following can be adopted. When the molding surface 34a is circular in plan view, the diameter c can be, for example, 20 mm or more, preferably 23 mm or more, more preferably 25 mm or more, and can be, for example, 80 mm or less, preferably 60 mm or less, more preferably 50 mm or less.

[0034] The capacity of the cavity 36 is preferably 5 cm 3 or more, more preferably 15 cm 3 or more, even more preferably 25 cm 3 or more, and preferably 150 cm 3 or less, more preferably 120 cm 3 or less, even more preferably 100 cm 3 or less, even more preferably 80 cm 3 or less, even more preferably 60 cm 3 or less, even more preferably 45 cm 3 or less. By setting the value of the capacity of the cavity 36 as described above, it becomes possible to further suppress the occurrence of surface roughness and flow marks.

[0035] In the present embodiment, the portion constituting the molding surface 32a of the first mold 32 is configured to be slidable, and by moving this portion in the direction of the second mold, the space formed between these molds is compressed, and an injection compression molding apparatus configured such that the above-described cavity is formed can also be used.

[0036] <Method for manufacturing an optical member> The method for manufacturing an optical member of the present embodiment uses the above-described injection molding apparatus and includes the following steps. Step (1): In the cylinder 22, melt a resin composition containing a copolymer of ethylene or α-olefin and a cyclic olefin. Step (2): Using the screw 24, inject the molten resin composition through the gate section 38 and fill it into the cavity.

[0037] [Step (1)] In step (1), a resin composition containing ethylene or a copolymer of α-olefin and a cyclic olefin is introduced into the cylinder 22 via the hopper 26, and the resin composition is heated and melted in the cylinder 22. Furthermore, the resin composition is extruded by rotating the screw 24 inside the cylinder 22.

[0038] The temperature of the molten resin composition (cylinder setting temperature) can be appropriately determined according to the glass transition temperature (Tg) and melting point (Tm) of the resin, but for example, it is "Tg + 100°C" or higher, preferably "Tg + 120°C" or higher, and for example, "Tg + 180°C" or lower, preferably "Tg + 170°C" or lower. Furthermore, the rotational speed of the screw is not particularly limited, but is, for example, 10 rpm or more and, for example, 300 rpm or less, and is appropriately selected within this range.

[0039] (Resin composition) The resin composition in this embodiment will now be described. The resin composition of this embodiment includes a copolymer of ethylene or an α-olefin and a cyclic olefin.

[0040] The copolymer according to this embodiment preferably has, from the viewpoint of further improving heat resistance and moldability while maintaining a good balance of transparency and refractive index performance of the resulting molded article, a repeating unit (a) derived from at least one olefin represented by the following general formula (I), and a repeating unit (b) derived from at least one cyclic olefin selected from the group consisting of a repeating unit represented by the following general formula (II), a repeating unit represented by the following general formula (III), a repeating unit represented by the following general formula (IV), a repeating unit represented by the following general formula (V), and a repeating unit represented by the following general formula (VI).

[0041] For example, repeating unit (a) may contain two or more types, such as ethylene and propylene. Repeating unit (b) may contain two or more types selected from repeating units represented by the same general formula, or it may contain two or more types selected from repeating units represented by different general formulas.

[0042] [ka]

[0043] In the above general formula (I), R 300 This represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms.

[0044] [ka]

[0045] In the above general formula (II), u is 0 or 1, v is 0 or a positive integer, preferably an integer between 0 and 2, more preferably 0 or 1, w is 0 or 1, R 61 ~R 78 Furthermore, R a1 and R b1 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R 75 ~R 78 These elements may be bonded to each other to form a monocycle or polycycle.

[0046] [ka]

[0047] In the above general formula (III), x and d are integers of 0 or greater than or equal to 1, preferably integers of 0 or greater than or equal to 2, more preferably 0 or 1, and y and z are 0, 1 or 2, R 81 ~R99 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group which is 6 to 20 carbon atoms or an alkoxy group, and R 89 and R 90 The carbon atom to which it is bonded, and R 93 The carbon atom or R to which it is bonded 91 The carbon atom to which it is bonded may be directly bonded or bonded via an alkylene group having 1 to 3 carbon atoms, and when y=z=0, R 95 and R 92 or R 95 and R 99 These elements may be bonded to each other to form a monocyclic or polycyclic aromatic ring.

[0048] [ka]

[0049] In the above general formula (IV), n and m are each independently 0, 1, or 2, and q is 1, 2, or 3. m is preferably 0 or 1, and more preferably 1. n is preferably 0 or 1, and more preferably 0. q is preferably 1 or 2, and more preferably 1.

[0050] R 18 ~R 31 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and R 18 ~R 31 Each of these is preferably independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrogen atom.

[0051] Also, when q=1, R 28 and R 29 , R 29 and R 30 , R 30 and R31 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 28 and R 28 , R 28 and R 29 , R 29 and R 30 , R 30 and R 31 , R 31 and R 31 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may be an aromatic ring.

[0052] [ka]

[0053] In the above general formula (V), R 100 , R 101 These elements may be identical or different from each other, and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, where f is an integer between 1 and 18.

[0054] [ka]

[0055] In the above general formula (VI), q is 1, 2, or 3, and R 32 ~R 39 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and when q=1, R 36 and R 37 , R 37 and R 38 , R 38 and R 39 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 36 and R 36 , R 36 and R 37 , R 37 and R 38 , R 38 and R 39, R 39 and R 39 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may have a double bond, and the monocycle or polycycle may be an aromatic ring.

[0056] Among the repeating units (b) represented by general formulas (II), (III), (IV), (V), or (VI), it is preferable that the repeating unit is represented by general formula (II). Furthermore, it is preferable to include a repeating unit represented by general formula (II) and any of the repeating units represented by general formulas (III), (IV), (V), or (VI). Furthermore, it is more preferable to have repeating units represented by general formulas (II) and (VI).

[0057] One of the copolymerization raw materials for the copolymer according to this embodiment is an olefin monomer that undergoes addition copolymerization to form a structural unit represented by the above general formula (I). Specifically, an olefin monomer represented by the following general formula (Ia), which corresponds to the above general formula (I), is used.

[0058] [ka]

[0059] In the above general formula (Ia), R 300The group represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms. Examples of olefin monomers represented by the above general formula (Ia) include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, and 1-eicosene. From the viewpoint of obtaining molded articles with superior heat resistance, mechanical properties, and optical properties, at least one selected from the group consisting of ethylene and propylene is preferred, and ethylene is more preferred. Two or more olefin monomers represented by the above general formula (Ia) may be used.

[0060] When the total amount of constituent units constituting the cyclic olefin copolymer according to this embodiment is set to 100 mol%, the proportion of repeating units (a) derived from olefins is preferably 5 mol% to 95 mol%, more preferably 20 mol% to 90 mol%, even more preferably 40 mol% to 85 mol%, and even more preferably 50 mol% to 80 mol%. Furthermore, the proportion of repeating units (a) derived from olefins is, 13 It can be measured by 13C-NMR.

[0061] One of the copolymerization raw materials for the copolymer according to this embodiment is a cyclic olefin monomer that is added copolymerized to form a repeating unit (b) derived from a cyclic olefin represented by the above general formula (II), (III), (IV), (V), or (VI). Specifically, cyclic olefin monomers represented by general formulas (IIa), (IIIa), (IVa), (Va), and (VIa), which correspond to the above general formulas (II), (III), (IV), (V), and (VI), respectively, are used.

[0062] [ka]

[0063] In the above general formula (IIa), u is 0 or 1, v is 0 or a positive integer, preferably an integer between 0 and 2, more preferably 0 or 1, w is 0 or 1, R 61 ~R 78 Furthermore, R a1 and R b1 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R 75 ~R 78 These elements may be bonded to each other to form a monocycle or polycycle.

[0064] [ka]

[0065] In the above general formula (IIIa), x and d are integers of 0 or greater than or equal to 1, preferably integers of 0 or greater than or equal to 2, more preferably 0 or 1, and y and z are 0, 1 or 2, R 81 ~R 99 These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group which is 6 to 20 carbon atoms or an alkoxy group, and R 89 and R 90 The carbon atom to which it is bonded, and R 93 The carbon atom or R to which it is bonded 91 The carbon atom to which it is bonded may be directly bonded or bonded via an alkylene group having 1 to 3 carbon atoms, and when y=z=0, R 95 and R 92 or R 95 and R 99These elements may be bonded to each other to form a monocyclic or polycyclic aromatic ring.

[0066] [ka]

[0067] In the above general formula (IVa), n and m are each independently 0, 1, or 2, and q is 1, 2, or 3. m is preferably 0 or 1, and more preferably 1. n is preferably 0 or 1, and more preferably 0. q is preferably 1 or 2, and more preferably 1.

[0068] R 18 ~R 31 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and R 18 ~R 31 Each of these is preferably independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrogen atom.

[0069] Also, when q=1, R 28 and R 29 , R 29 and R 30 , R 30 and R 31 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 28 and R 28 , R 28 and R 29 , R 29 and R 30 , R 30 and R 31 , R 31 and R 31 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may be an aromatic ring.

[0070] [ka]

[0071] In the above general formula (Va), R 100 , R 101 These elements may be identical or different from each other, and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, where f is an integer between 1 and 18.

[0072] [ka]

[0073] In the above general formula (VIa), q is 1, 2, or 3, preferably 1 or 2, and more preferably 1.

[0074] R 32 ~R 39 Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms that may be substituted with a halogen atom other than a fluorine atom. R 32 ~R 39 Each of these is preferably independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrogen atom.

[0075] Also, when q=1, R 36 and R 37 , R 37 and R 38 , R 38 and R 39 They may be bonded to each other to form a monocycle or polycycle, and when q=2 or 3, R 36 and R 36 , R 36 and R 37 , R 37 and R 38 , R 38 and R 39 , R 39 and R 39 These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may have a double bond, and the monocycle or polycycle may be an aromatic ring.

[0076] Furthermore, examples of hydrocarbon groups having 1 to 20 carbon atoms include, independently, alkyl groups having 1 to 20 carbon atoms, cycloalkyl groups having 3 to 15 carbon atoms, and aromatic hydrocarbon groups. More specifically, alkyl groups include methyl, ethyl, propyl, isopropyl, amyl, hexyl, octyl, decyl, dodecyl, and octadecyl groups; cycloalkyl groups include cyclohexyl groups; and aromatic hydrocarbon groups include aryl or aralkyl groups such as phenyl, tolyl, naphthyl, benzyl, and phenylethyl groups. These hydrocarbon groups may be substituted with halogen atoms other than fluorine atoms.

[0077] By using the olefin monomer represented by the general formula (Ia), or the cyclic olefin monomer represented by the general formulas (IIa), (IIIa), (IVa), (Va), or (VIa) as copolymerization components, the solubility of the cyclic olefin polymer in solvents is further improved, resulting in better moldability and increased product yield.

[0078] Specific examples of cyclic olefin monomers represented by general formula (IIa), (IIIa), or (Va) include the olefin monomers described in paragraphs 0037 to 0063 of International Publication No. 2006 / 118261.

[0079] Specifically, bicyclo-2-heptene derivatives (bicyclohept-2-ene derivatives), tricyclo-3-decene derivatives, tricyclo-3-undecene derivatives, tetracyclo-3-dodecene derivatives, pentacyclo-4-pentadecene derivatives, pentacyclopentadecadiene derivatives, pentacyclo-3-pentadecene derivatives, pentacyclo-4-hexadecene derivatives, pentacyclo-3-hexadecene derivatives, hexacyclo-4-heptadecene derivatives, heptacyclo-5-eicosene derivatives Examples include conductors, heptacyclo-4-eicosene derivatives, heptacyclo-5-heneicosene derivatives, octacyclo-5-docosene derivatives, nonacyclo-5-pentacosene derivatives, nonacyclo-6-hexacosene derivatives, cyclopentadiene-acenaphthylene adducts, 1,4-methano-1,4,4a,9a-tetrahydrofluorene derivatives, 1,4-methano-1,4,4a,5,10,10a-hexahydroanthracene derivatives, and cycloalkylene derivatives having 3 to 20 carbon atoms.

[0080] Among the cyclic olefin monomers represented by general formulas (IIa), (IIIa), (IVa), (Va), or (VIa), the cyclic olefin represented by general formula (IIa) is preferred.

[0081] Furthermore, it is preferable to use either a cyclic olefin represented by general formula (IIa) or a cyclic olefin represented by general formula (IIIa), (IVa), (Va), or (VIa).

[0082] As cyclic olefin monomers represented by the above general formula (IIa), bicyclo[2.2.1]-2-heptene (also called norbornene) and tetracyclo[4.4.0.1 2,5 .1 7,10 It is preferable to use at least one selected from the group consisting of ]-3-dodecene (also called tetracyclododecene), and tetracyclo[4.4.0.1 2,5 .1 7,10 It is more preferable to use ]-3-dodecene. These cyclic olefins have a rigid ring structure, which has the advantage of making it easier to maintain the elastic modulus of the copolymer and molded article.

[0083] It is preferable to use a monomer in formula (VIa) where q=1 as the cyclic olefin monomer represented by the above general formula (VIa). Since these cyclic olefins have one benzene ring, they have the advantage of making it easier to obtain a resin composition that is less prone to coloring compared to cases where there are two or more benzene rings. It is preferable to use benzonorbornadiene. The advantage of using benzonorbornadiene is that it has an aromatic ring, which allows for a higher refractive index of the resin composition.

[0084] The repeating units derived from the above cyclic olefins are bicyclo[2.2.1]-2-heptene, tetracyclo[4.4.0.1 2,5 .1 7,10 Preferably, the repeating unit is derived from at least one compound selected from the group consisting of ]-3-dodecene and benzonorbornadiene.

[0085] When the total amount of constituent units constituting the copolymer according to this embodiment is set to 100 mol%, the proportion of repeating units (b) derived from the cyclic olefin monomer (b) is preferably 5 mol% to 95 mol%, more preferably 10 mol% to 80 mol%, even more preferably 15 mol% to 60 mol%, and even more preferably 20 mol% to 50 mol%.

[0086] The copolymerization type of the copolymer according to this embodiment is not particularly limited, but examples include random copolymers and block copolymers. In this embodiment, from the viewpoint of obtaining optical components with excellent optical properties such as transparency, refractive index and birefringence, and high precision, it is preferable to use a random copolymer as the copolymer according to this embodiment. The copolymer according to this embodiment may contain one or more of the above-mentioned copolymers.

[0087] The copolymer according to this embodiment is ethylene and tetracyclo[4.4.0.1 2,5 .1 7,10Random copolymers with ]-3-dodecene, random copolymers of ethylene and bicyclo[2.2.1]-2-heptene, and ethylene and tetracyclo[4.4.0.1 2,5 .1 7,10 Preferably, it is at least one selected from the group consisting of a random copolymer of ]-3-dodecene and benzonorbornadiene, and is ethylene and tetracyclo[4.4.0.1 2,5 .1 7,10 Random copolymer with ]-3-dodecene and ethylene and tetracyclo[[4.4.0.1 2,5 .1 7,10 At least one selected from the group consisting of random copolymers of ]-3-dodecene and benzonorbornadiene is more preferred.

[0088] (Other ingredients) In addition to the cyclic olefin copolymer, the resin composition in this embodiment may contain known additives as optional components, provided that they do not impair the good physical properties of the optical component in this embodiment.

[0089] Examples of additives include hydrophilic stabilizers, hydrophilic agents, antioxidants, secondary antioxidants, lubricants, mold release agents, anti-fogging agents, weather-resistant stabilizers, light-resistant stabilizers, UV absorbers, antistatic agents, and metal deactivators. Among the above, the resin composition in this embodiment preferably contains a hydrophilic stabilizer. Including a hydrophilic stabilizer is more preferable because it can suppress the deterioration of optical performance under high temperature and high humidity conditions.

[0090] The hydrophilic stabilizer is preferably a fatty acid ester of a fatty acid and a polyhydric alcohol. More preferably, it is a fatty acid ester of a fatty acid and a polyhydric alcohol having one or more ether groups.

[0091] In this embodiment, the lower limit of the copolymer content in the resin composition is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the total mass of the resin composition is considered to be 100% by mass. By having a copolymer content in the resin composition that is above the above lower limit, the optical performance can be further improved. The upper limit of the content of cyclic olefin copolymer in the resin composition is not particularly limited, but is, for example, 100% by mass or less.

[0092] The glass transition temperature (Tg) of the resin composition of this embodiment is preferably 120°C or higher, more preferably 125°C or higher, even more preferably 130°C or higher, and preferably 160°C or lower, more preferably 155°C or lower, and even more preferably 150°C or lower. When the glass transition temperature (Tg) of the resin composition is within the above range, when combined with the injection rate ratio and cylinder setting temperature in this embodiment, which will be described later, it is possible to achieve better mold transferability, have the desired shape, and further suppress surface roughness of the optical surface. Furthermore, when the molded body is used as an optical component that requires heat resistance, such as an in-vehicle camera lens or a camera lens for a portable device, sufficient heat resistance can be obtained.

[0093] In this embodiment, if the resin composition contains two or more types of copolymers, or if it contains other components having a glass transition temperature, and there are multiple glass transition temperatures, the higher glass transition temperature will be adopted.

[0094] The glass transition temperature (Tg) of the resin composition of this embodiment can be measured, for example, using an RDC220 manufactured by SII Nanotechnology, Inc., by raising the temperature from room temperature to 200°C at a rate of 10°C / min under a nitrogen atmosphere, holding it for 5 minutes, then lowering the temperature to 30°C at a rate of 10°C / min, holding it for 5 minutes, and then raising the temperature to 200°C at a rate of 10°C / min.

[0095] [Process (2)] In step (2), the molten resin composition obtained in step (1) is injected through the gate section 38 using the screw 24 and filled into the cavity 36. Specifically, as the tip of the cylinder 22 opens and the screw 24 moves forward, the molten resin composition passes through the sprue 44 and runner 40 and is injected through the gate section 38.

[0096] In this embodiment, the manufacturing method satisfies the following conditions (1) and (2) in step (2). (Condition 1) The ratio b / a of the injection rate b of the molten resin composition after it has passed the exit of the gate section, calculated by formula (2) below, to the injection rate a of the molten resin composition when it has passed from the entrance to the exit of the gate section, calculated by formula (1) below, is 3 or more and 16 or less. (Condition 2) The above ejection ratio b is 45cm 3 / second or more 100cm 3 It is less than / second. a = σ × v a (1) b = σ × v b (2) σ: Cross-sectional area inside the cylinder of the injection molding apparatus described above. v a : The forward speed of the screw as the tip of the molten resin composition passes from the entrance to the exit of the gate section. v b : The forward speed of the screw after the tip of the molten resin composition has passed the exit of the gate section.

[0097] The above b / a is preferably 4 or more, more preferably 5 or more, even more preferably 6 or more, even more preferably 7 or more, and preferably 15 or less, more preferably 14 or less, and even more preferably 12 or less. By setting the value of b / a as described above, it is possible to further suppress the occurrence of surface roughness and flow marks.

[0098] The above a (the injection rate when the leading edge of the molten resin composition passes from the entrance to the exit of the gate section) is preferably 1 cm 3 / second or more, comfortably 3cm 3 / second or more, more preferably 5cm 3 / second or more, more preferably 7cm 3 It is 20 cm / second or more, and preferably 20 cm 3 Less than / second, more preferably 18cm 3 Less than or equal to / second, more preferably 16cm 3 It is less than / second. By setting the value of a as described above, it becomes possible to further suppress the occurrence of surface roughness and flow marks.

[0099] The above b (the injection rate after the leading edge of the molten resin composition has passed the exit of the gate section) is preferably 40 cm 3 More than / second, comfortably 50cm 3 / second or more, more preferably 60cm / second 3 It is 100 cm / second or more, and preferably 100 cm 3 Less than / second, more preferably 80cm / second 3 Less than or equal to / second, more preferably 70cm 3 It is less than / second. By setting the value of b as described above, it becomes possible to further suppress the occurrence of surface roughness and flow marks.

[0100] In the manufacturing method of this embodiment, it is preferable that the following conditions (3) and (4) are met in step (2). This makes it possible to further suppress the occurrence of surface roughness and flow marks. (Condition 3) The ratio x / a of the injection rate x of the molten resin composition before the tip of the molten resin composition passes through the entrance of the gate section, as calculated by the following formula (3), to the injection rate a is 1.0 or more and 6 or less. (Condition 4) The above ejection ratio x is 6 cm 3 / second or more 30cm 3 It is less than / second. x = σ × v x (3) σ: Cross-sectional area inside the cylinder of the injection molding machine described above. v x : The forward speed of the screw before the tip of the molten resin composition passes through the entrance of the gate section.

[0101] The above x / a is preferably 1 or more, more preferably 1.4 or more, even more preferably 1.8 or more, and preferably 6 or less, more preferably 5 or less, and even more preferably 4 or less. By setting the value of x / a as described above, it is possible to further suppress the occurrence of surface roughness and flow marks.

[0102] The above x (the injection rate before the leading edge of the molten resin composition passes through the entrance of the gate section) is preferably 6 cm 3 / second or more, more preferably 8cm 3 / second or more, more preferably 10cm 3 / second or more, and more preferably 12cm 3 / second or more, and more preferably 14cm 3 It is 1 / second or more, and preferably 30cm 3 Less than / second, more preferably 25cm 3 Less than or equal to / second, more preferably 20cm 3 It is less than / second. By setting the value of x as described above, it is possible to further suppress the occurrence of surface roughness and flow marks.

[0103] In step (2), the shear rate γ, determined by the following formula (4), is preferably 300 / second or more, more preferably 500 / second or more, and even more preferably 1000 / second or more. There is no particular upper limit to the shear rate γ, but for example, it is 5000 / second or less. By setting the value of the shear rate γ as described above, it is possible to further suppress the occurrence of surface roughness and flow marks. γ = πDN / h (4) D: Screw diameter N: Screw rotation speed h: Screw groove depth

[0104] Step (2) can also be performed using an injection compression molding apparatus. In other words, as shown in Figure 1, an injection compression molding apparatus can be used that is configured such that the first mold 32 moves toward the second mold 34, compressing the space formed between these molds to form a cavity 36. Specifically, the portion constituting the molding surface 32a of the first mold 32 is configured to be slidable, and this portion moves toward the second mold 34, compressing the space formed between these molds to form a cavity 36.

[0105] In step b, when using an injection compression molding apparatus, the molten resin composition is injected into the space through the gate 38 using the screw 24, and the portion constituting the molding surface 32a of the first mold 32 is moved toward the second mold 34, thereby compressing the space into the shape of a cavity 36, and pressing the molten resin composition to fill the cavity 36.

[0106] The length (compression allowance) compressed from the above space into the cavity 36 varies depending on the size of the cavity 36, but can be, for example, 500 μm or more, preferably 1000 μm or more, more preferably 1500 μm or more, and can be, for example, 5000 μm or less, 4000 μm or less, and more preferably 3000 μm or less. By adjusting the injection rate and applying stress to the molten resin composition through compression molding, the mold transferability is improved. As a result, it is possible to obtain an optical component with a desired shape and a smooth surface with reduced surface roughness on the optical surface, and furthermore, an optical component with lower birefringence.

[0107] After step b, the resin in the mold is cooled and solidified according to a conventional method, and then the mold is opened to remove the resin molded product (optical component). The cooling time is not particularly limited, but is usually 1 to 500 seconds.

[0108] [Optical components] The resin molded body (optical member) obtained by the manufacturing method of this embodiment has a circular effective optical surface (diameter b) and a circular effective optical surface (diameter c) on its back surface. The manufacturing method of this embodiment exhibits excellent mold transfer properties, and the optical surface of the resulting optical component has suppressed surface roughness.

[0109] The optical component according to this embodiment contains a cyclic olefin copolymer (A) and therefore exhibits excellent optical performance. For this reason, it can be suitably used as an optical component in optical systems where high-precision image recognition is required. An optical component is a part used in optical system equipment, and specifically includes sensor lenses, pickup lenses, projector lenses, prisms, fθ lenses, imaging lenses, light guide plates, etc. From the viewpoint of the effects of this embodiment, it can be suitably used as an fθ lens, imaging lens, sensor lens, prism, or light guide plate.

[0110] Examples of lens shapes include convex lenses with spherical surfaces on both sides, concave lenses with spherical surfaces on both sides, lenses with one spherical and convex surface and the other aspherical surface, lenses with one spherical and concave surface and the other aspherical surface, diffractive lenses, Fresnel lenses, wafer lenses, wafer lens arrays, and laminates of wafer lens arrays.

[0111] In particular, the optical element according to this embodiment has a desired shape and suppresses surface roughness of the optical surface, so it can be used not only for the conventional optical element applications described above, but also for optical elements such as automotive camera lenses and camera lenses for portable devices (mobile phones, smartphones, tablets, etc.). Examples of automotive camera lenses and camera lenses for portable devices include view camera lenses, sensing camera lenses, light focusing lenses for head-up displays, light diffusing lenses for head-up displays, and lenses for various optical devices such as PC cameras, mobile phone cameras, smartphone cameras, tablet terminal cameras, mobile device cameras, digital cameras, and medical device cameras. The automotive camera may capture visible images, infrared images, or both, and if it captures visible images, it may be a black and white image or a color image. Other applications include automotive interior panels, automotive lamp lenses, automotive inner lenses, automotive lens protective covers, and automotive light guides. The optical element according to this embodiment is particularly suitable for automotive applications.

[0112] Although embodiments of the present invention have been described above, these are merely examples, and various other configurations can be adopted as long as they do not impair the effects of the present invention. [Examples]

[0113] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

[0114] [Preparation of resin composition] <Preparation of catalyst> Ethyl aluminum sesquichloride (Al(C2H5) 1.5 C l1.5 The solution was diluted with cyclohexane to prepare an organoaluminum compound catalyst solution.

[0115] <Polymerization> In a stirred polymerizer, the organoaluminum compound catalyst solution prepared by the above method is used as a catalyst to polymerize ethylene and tetracyclo[4.4.0.1 2,5 .1 7,10 A copolymerization reaction of ]-3-dodecene was carried out to obtain a copolymer solution. Here, ethylene was supplied into the polymerizer along with hydrogen gas.

[0116] <Decalcification> Water and an aqueous sodium hydroxide solution were added to the obtained copolymer solution to stop the polymerization reaction and remove the catalyst residue present in the copolymer solution (decalcification). Pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] was added to the decalcified solution as a stabilizer and mixed in a stirring tank for 1 hour.

[0117] <Solvent removal> The solution, mixed with a stabilizer, is heated to 180°C to remove the solvent and unreacted monomers, thereby obtaining a molten cyclic olefin copolymer (ethylene and tetracyclo[4.4.0.1 2,5 .1 7,10 A random copolymer with ]-3-dodecene was obtained. Furthermore, the glass transition temperature (Tg) of the cyclic olefin copolymer obtained by the method described later was evaluated to be 155°C.

[0118] <Extrusion> 100 parts by mass of the obtained cyclic olefin copolymer and 0.9 parts by mass of a fatty acid ester (Rikemar DO-100, manufactured by Riken Vitamin Co., Ltd.) were kneaded together and pelletized. The resulting pellets were dried with hot air at a temperature of 100°C for 4 hours to obtain a resin composition.

[0119] [Measurement of glass transition temperature] The glass transition temperature (Tg) of the obtained resin composition was measured under an N2 (nitrogen) atmosphere using a Shimadzu Science DSC-6220. Details are as follows. The resin composition was heated from room temperature to 200°C at a heating rate of 10°C / min, held for 5 minutes, and then cooled to -20°C at a cooling rate of 10°C / min, held for 5 minutes. The glass transition point of the resin composition was then obtained from the endothermic curve during the heating process to 200°C at a heating rate of 10°C / min. The glass transition temperature of the resin composition was 130°C.

[0120] [Fabrication of optical components] <Example 1> An optical lens was obtained by injection molding the resulting resin composition using a FANUC ROBOSHOT α-S100iB injection molding apparatus, as shown in Figure 1. The details of the injection molding equipment used are as follows: • Cavity volume: 41 cm³ 3 • Width between the first mold 32 and the second mold 34 in gate section 38 (width of gate section 38 when viewed from the direction shown in Figure 1): 1.5 mm • Width of the first mold 32 (second mold 34) in gate section 38 (width of gate section 38 when viewed from a direction perpendicular to the direction in Figure 1): 10.0 mm • Width between the first mold 32 and the second mold 34 in the runner section 40 (width of the runner section 40 as viewed from the direction in Figure 1): 6.0 mm • Width of the first mold 32 (second mold 34) in the runner section 40 (width of the runner section 40 when viewed from a direction perpendicular to the direction in Figure 1): 6.0 mm Furthermore, details of the injection molding process are as follows: First, the forward distance of the screw 24 was gradually increased from the metering completion position in the cylinder 22, and the relationship between the forward distance of the screw 24 and the position of the tip of the molten resin composition was investigated. At this time, no holding pressure was applied to prevent the resin from being injected due to holding pressure. Next, the temperature of the cylinder 22 was set to 260°C and the temperature of the mold 30 to 130°C. The resin composition was then injection molded while adjusting the forward speed of the screw 24 by checking the forward distance of the screw 24 (the position of the tip of the resin composition) to obtain an optical lens. Specifically, the resin composition was injection molded while adjusting the forward speed of the screw 24 so that the injection rates x, a, and b were as follows. Injection rate x before the leading edge of the molten resin composition passes through the entrance of gate section 38: 16 cm 3 / sec The injection rate a: 5cm when the leading edge of the molten resin composition passes from the entrance to the exit of the gate section 38. 3 / sec Injection rate b after the leading edge of the molten resin composition passes through the exit of gate section 38: 64 cm 3 / sec

[0121] The ejection rate was calculated from the cross-sectional area inside the cylinder 22 and the forward speed of the screw 24 using the following formula (1A). Ejection rate = Cross-sectional area inside cylinder 22 (cm²) 2 ) × Forward speed of screw 24 (cm / sec) (1A)

[0122] <Examples 2-6, Comparative Examples 1-9> A resin molded product (optical component) optical lens was obtained in the same manner as in Example 1, except that the injection rate x before the tip of the molten resin composition passes through the entrance of the gate section 38, the injection rate a when the tip of the molten resin composition passes from the entrance to the exit of the gate section 38, and the injection rate b after the tip of the molten resin composition passes through the exit of the gate section 38 were set to the conditions shown in Table 1.

[0123] <Comparative Examples 10-13> A resin molded product (optical component) optical lens was obtained in the same manner as in Example 1, except that a ROBOSHOT α-S30iA manufactured by FANUC Corporation was used as the injection molding apparatus, and the injection rate x before the leading edge of the molten resin composition passed through the entrance of the gate section 38, the injection rate a when the leading edge of the molten resin composition passed from the entrance to the exit of the gate section 38, and the injection rate b after the leading edge of the molten resin composition passed through the exit of the gate section 38 were set to the conditions shown in Table 1. The details of the injection molding equipment used are as follows: · Cavity volume: 12 cm 3 · Width between the first mold 32 and the second mold 34 in the gate section 38 (width of the gate section 38 when viewed from the direction of FIG. 1): 1.5 mm · Width of the first mold 32 (second mold 34) in the gate section 38 (width of the gate section 38 when viewed from the direction orthogonal to the direction of FIG. 1): 10.0 mm · Width between the first mold 32 and the second mold 34 in the runner section 40 (width of the runner section 40 when viewed from the direction of FIG. 1): 6.0 mm · Width of the first mold 32 (second mold 34) in the runner section 40 (width of the runner section 40 when viewed from the direction orthogonal to the direction of FIG. 1): 6.0 mm

[0124] [Surface roughness] The central part of the optical effective surface of the optical member formed by the molding surface 32a of the first mold 32 was observed with an optical microscope at a magnification of 100 times and evaluated according to the following <standard>. The results are shown in Table 1. <Standard> A: Surface roughness occurred at 0 or more and 5 or less locations B: Surface roughness occurred at 6 or more and 10 or less locations C: Surface roughness occurred at 11 or more and 15 or less locations D: Surface roughness occurred at 16 or more locations

[0125] FIG. 2 shows optical microscope photographs of the optical effective surface (surface roughness A) of the optical member obtained in Example 5, FIG. 3 shows the optical effective surface (surface roughness B) of the optical member obtained in Example 2, FIG. 4 shows the optical effective surface (surface roughness C) of the optical member obtained in Comparative Example 7, and FIG. 5 shows the optical effective surface (surface roughness D) of the optical member obtained in Comparative Example 4. In FIGS. 2 to 5, the locations where surface roughness occurred were marked so as to surround them.

[0126] [Flow mark] The central part of the optical effective surface of the optical member formed by the molding surface 32a of the first mold 32 was visually observed and evaluated according to the following <standard>. The results are shown in Table 1. Evaluated according to the following criteria. <Standards> OK: No flow marks were generated. Unacceptable: Flow marks were present.

[0127] [Table 1]

[0128] The optical components manufactured by the manufacturing method of the embodiment showed suppressed surface roughness and flow marking. This indicates that the manufacturing method of this embodiment makes it possible to manufacture optical components with suppressed surface roughness and flow marking. [Explanation of symbols]

[0129] 10 Injection molding equipment 20 Injection Units 22 cylinders 24 Screws 26 Hopper 30 molds 32 First mold 32a Molding surface 34. Second mold 34a Molding surface 36 Cavity 38 Gate Section 40 Runners 44 Spruce

Claims

1. An injection unit comprising a cylinder and a screw inserted into the cylinder, A mold having a cavity for molding an optical component, and a gate section that serves as an injection passage for a resin composition from the injection unit into the cavity, A method for manufacturing an optical component using an injection molding apparatus, comprising: (1) A step of melting a resin composition containing ethylene or an α-olefin and a cyclic olefin in the cylinder, The process includes (2) using the screw to inject the molten resin composition through the gate section and fill the cavity, A method for manufacturing an optical member, wherein the above step (2) satisfies the following conditions (1) and (2). (Condition 1) The ratio b / a of the injection rate b after the tip of the molten resin composition has passed the exit of the gate section, calculated by formula (2) below, to the injection rate a when the tip of the molten resin composition has passed the exit of the gate section, calculated by formula (1) below, is 3 or more and 16 or less. (Condition 2) The ejection rate b is 45 cm ３ / second or more 100cm ３ It is less than / second. a=σ×v ａ (1) b=σ×v ｂ (2) σ: Cross-sectional area inside the cylinder of the injection molding apparatus. v ａ : The forward speed of the screw as the tip of the molten resin composition passes from the entrance to the exit of the gate section. v ｂ : The forward speed of the screw after the tip of the molten resin composition has passed the exit of the gate section.

2. The method for manufacturing an optical member according to claim 1, wherein the b / a is 7 or more and 16 or less.

3. A method for manufacturing an optical member according to claim 1 or 2, wherein the following conditions (3) and (4) are further satisfied in step (2). (Condition 3) The ratio x / a of the injection rate x of the molten resin composition before the leading edge passes through the entrance of the gate section, as calculated by the following formula (3), to the injection rate a is 1 or more and 6 or less. (Condition 4) The ejection rate x is 6 cm ３ / second or more 30cm ３ It is less than / second. x=σ×v ｘ (3) σ: Cross-sectional area inside the cylinder of the injection molding apparatus. v ｘ : The forward speed of the screw before the tip of the molten resin composition passes through the entrance of the gate section.

4. The method for manufacturing an optical member according to claim 1 or 2, wherein in step (2), the shear rate γ determined by the following formula (4) is 300 / second or more. γ = πDN / h (4) D: Screw diameter N: Screw rotation speed h: Screw groove depth

5. The cavity volume of the aforementioned mold is 5 cm³ ３ More than 150cm ３ The method for manufacturing an optical member according to claim 1 or 2, which is as follows:

6. The copolymer, A repeating unit (a) derived from at least one olefin represented by the following general formula (I), A repeating unit (b) derived from a cyclic olefin, selected from the group consisting of a repeating unit represented by the following general formula (II), a repeating unit represented by the following general formula (III), a repeating unit represented by the following general formula (IV), a repeating unit represented by the following general formula (V), and a repeating unit represented by the following general formula (VI), A method for manufacturing an optical member according to claim 1 or 2, comprising having 【Chemistry 1】 In the above general formula (I), R ３００ This represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 29 carbon atoms. 【Chemistry 2】 In the general formula (II) above, u is 0 or 1, v is 0 or a positive integer, w is 0 or 1, R ６１ ~R ７８ And R ａ１ and R ｂ１ These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, a halogenated alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, or an aromatic hydrocarbon group having 6 to 20 carbon atoms, R ７５ ~R ７８ These elements may be bonded to each other to form a monocycle or polycycle. 【Transformation 3】 In the above general formula (III), x and d are integers of 0 or 1 or greater, y and z are 0, 1 or 2, and R ８１ ~R ９９ These may be the same or different from each other, and are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group which is an alkyl group having 1 to 20 carbon atoms or a cycloalkyl group having 3 to 15 carbon atoms, an aromatic hydrocarbon group which is a 6 to 20 carbon atom or an alkoxy group, R ８９ and R ９０ The carbon atom to which it is bonded, and R ９３ The carbon atom or R to which it is bonded ９１ The carbon atom to which it is bonded may be directly bonded or bonded via an alkylene group having 1 to 3 carbon atoms, and when y = z = 0, R ９５ and R ９２ or R ９５ and R ９９ These elements may be bonded to each other to form a monocyclic or polycyclic aromatic ring. 【Chemistry 4】 In the above general formula (IV), n and m are each independently 0, 1, or 2, q is 1, 2, or 3, R １８ ~R ３１ Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and when q = 1, R ２８ and R ２９ , R ２９ and R ３０ , R ３０ and R ３１ They may be bonded to each other to form a monocycle or polycycle, and when q = 2 or 3, R ２８ and R ２８ , R ２８ and R ２９ , R ２９ and R ３０ , R ３０ and R ３１ , R ３１ and R ３１ These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may be an aromatic ring. 【Transformation 5】 In the above general formula (V), R １００ , R １０１ These elements may be the same or different from each other, and represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, where f is an integer between 1 and 18. 【Transformation 6】 In the above general formula (VI), q is 1, 2, or 3, and R ３２ ~R ３９ Each of these is independently a hydrogen atom, a halogen atom other than a fluorine atom, or a hydrocarbon group having 1 to 20 carbon atoms which may be substituted with a halogen atom other than a fluorine atom, and when q = 1, R ３６ and R ３７ , R ３７ and R ３８ , R ３８ and R ３９ They may be bonded to each other to form a monocycle or polycycle, and when q = 2 or 3, R ３６ and R ３６ , R ３６ and R ３７ , R ３７ and R ３８ , R ３８ and R ３９ , R ３９ and R ３９ These elements may be bonded to each other to form a monocycle or polycycle, and the monocycle or polycycle may have a double bond, and the monocycle or polycycle may be an aromatic ring.

7. The repeating unit (b) derived from the cyclic olefin in the copolymer is bicyclo[2.2.1]-2-heptene, tetracyclo[4.4.0.1 ２，５ 1. ７，１０ A method for producing an optical component according to claim 6, comprising a repeating unit derived from at least one compound selected from the group consisting of ]-3-dodecene and benzonorbornadiene.

8. The method for producing an optical member according to claim 6, wherein the repeating unit (a) derived from the olefin in the copolymer includes a repeating unit derived from ethylene.

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