JP5607936B2 - Manufacturing method of optical components - Google Patents

Description

  The present invention relates to a method for manufacturing an optical component such as an optical lens and a recording layer of an optical recording medium.

  An optical component, for example, an optical lens is formed in a predetermined three-dimensional shape such as a hemispherical shape so as to exhibit performances such as focusing and divergence of light. Moreover, optical recording media such as CD (Compact Disc) and DVD (Digital Versatile Disc) have a multilayer structure, and the surface (recording surface) of the recording layer is formed in a three-dimensional shape such as irregularities. Note that a metal layer is formed on the uneven recording surface of the recording layer of the optical recording medium, a resin layer is formed on the surface of the metal layer, and the surface of the resin layer is flat. .

  For three-dimensional optical parts such as the above optical lenses and optical recording media, as a manufacturing method for high density, high heat resistance, or low-cost production, a resin is used as a forming material, and a molding die is stamped on the resin. Thus, a method of manufacturing a three-dimensional optical component having the predetermined shape and the uneven shape has been studied.

  Such three-dimensional optical component manufacturing methods are roughly classified into two types from the viewpoint of dimensional stability. One is to supply a thermoplastic resin that has been heated and melted onto the substrate, and then press a molding die that has projections and depressions corresponding to optical components on the mold surface. In this method, the resin is cooled and then released to obtain a three-dimensional optical component made of a cured product of the thermoplastic resin on the substrate. The other is that a liquid or pasty photosensitive resin is supplied onto the substrate, and then a mold is pressed onto the photosensitive resin, and in this state, the lower substrate or the upper mold is passed through. Then, the photosensitive resin is exposed by light irradiation, and then released to obtain a three-dimensional optical component made of a cured product of the photosensitive resin on a substrate.

  The two types of manufacturing methods are generally selected based on the required heat-resistant temperature. That is, in a field where heat resistance is not required, a transparent thermoplastic resin such as PMMA (polymethyl methacrylate), polycarbonate, polynorbornene or the like is used. On the other hand, in fields where heat resistance is required, such as solder reflow and autoclave, a photosensitive resin containing an epoxy resin as a main resin component is used (for example, see Patent Document 1).

Japanese Patent No. 4262271

  By the way, in the above prior art, an optical component is irradiated with light through the light transmissive substrate from below in a state where a molding die is pressed onto a photosensitive resin supplied on the substrate (light transmissive substrate). In this method, the inside of the optical component is destroyed (cohesive failure) due to the force applied at the time of mold release due to the high adhesiveness between the photosensitive resin and the mold and insufficient curing of the photosensitive resin. Demolding may occur and defects may occur in optical components.

  As a countermeasure against the former (high adhesiveness between the photosensitive resin and the mold) among the causes of the above-mentioned mold release failure, there is a method of applying a mold release agent to the mold surface of the mold. However, the countermeasure requires a release agent coating step, which not only reduces the production efficiency, but also may cause the release agent to be transferred to the surface of the molded product and reduce the quality of the optical component.

  On the other hand, as a countermeasure against the latter of the causes of the above-mentioned mold release failure (insufficient curing of the photosensitive resin), from the two aspects of improving the resin composition of the photosensitive resin itself or improving the manufacturing method of the optical component, A method for improving curability is mentioned. Among them, in the former case (improvement of the resin composition of the photosensitive resin itself), to increase the sensitivity to light, increase the amount of photopolymerization initiator (curing agent) added or use a sensitizer together. Etc. are performed. However, since the photopolymerization initiator and the sensitizer are compounds having a chromophore, the transparency of the manufactured optical component decreases as the amount of the photopolymerization initiator and the sensitizer increases. Since optical components such as optical lenses are components that allow light to pass through, a decrease in transparency is a problem that should be avoided. On the other hand, in the latter case (improvement of the manufacturing method of the optical component), it is possible to increase the light irradiation time in order to improve the curability of the photosensitive resin, but this method deteriorates the production efficiency.

  The present invention has been made in view of such circumstances, and without having to apply a release agent to the mold surface of the molding die, without having to change the resin composition of the photosensitive resin itself. An object of the present invention is to provide a method of manufacturing an optical component that can improve the curability of the photosensitive resin and improve the mold releasability while obtaining the same illuminance and irradiation time, thereby obtaining an optical component free from defects. .

In order to achieve the above object, a method for manufacturing an optical component according to the present invention supplies a photosensitive resin onto a light-transmitting substrate, and the photosensitive resin has an unevenness for transfer corresponding to the optical component on a mold surface. The photosensitive resin is exposed to light by irradiating the photosensitive resin that has been embossed with the molding die in that state, through the light-transmitting substrate under the light-transmitting substrate. a method of manufacturing an optical component comprising a cured product of the photosensitive resin, in the mold surface of the mold, the wavelength 365nm light reflectance, by to set more than 46%, from the mold surface The configuration is such that the releasability of the optical component is improved .

  In the present invention, “optical component” includes, for example, an optical lens, an optical waveguide, an optical fiber core, a recording layer in an optical recording medium such as a CD, and the like.

  In order to solve the above-mentioned problems, the present inventors irradiate light through the light-transmitting substrate and irradiate the optical component in a state where a molding die is pressed on the photosensitive resin supplied onto the light-transmitting substrate. In the method to obtain, the research was repeated about the method of improving the sclerosis | hardenability of the whole photosensitive resin by improvement of a shaping | molding die. In the course of the research, the idea was that the irradiation light for curing the photosensitive resin was reflected by the mold and the reflected light was used to improve the curability of the entire photosensitive resin. As a result of further research, when the reflectance of light having a wavelength of 365 nm on the mold surface of the mold is set to 46% or more, the energy of the reflected light is sensitive to irradiation light including the wavelength of 365 nm. It became an amount effective for curing of the resin, and it was found that the direct light of the light irradiation and the reflected light combined to increase the curability of the entire photosensitive resin. And because of the increased curability of the entire photosensitive resin, the inside of the optical component will not be destroyed (cohesive failure) even if force is applied during release, resulting in improved release properties. And found that an optical component having no defect can be obtained.

  Here, the wavelength “365 nm” serving as a reference for the reflectance will be described. That is, the spectral distribution of the irradiation light (light emitted from the light source lamp) for curing the photosensitive resin has peaks in a plurality of wavelength ranges, and in particular, a spectrum having a large peak in the vicinity of 350 nm. Is shown. For this reason, it is estimated that the wavelength around 350 nm has a high influence on the curing of the photosensitive resin. Usually, the illuminance meter used for adjusting the output of the light source lamp has a sensitivity of 365 nm. Therefore, the wavelength “365 nm” is used as a reference for reflectance.

The method for producing an optical component of the present invention is to manufacture an optical component by irradiating light through the light transmissive substrate in a state where a molding die is pressed against a photosensitive resin supplied on the light transmissive substrate. As the mold, a mold whose reflectance of light having a wavelength of 365 nm is set to 46% or more on the mold surface is used. Therefore, for curing the photosensitive resin by light irradiation, not only the direct light of the light irradiation, the reflected light from the mold also can be effectively utilized, and they direct light and reflected light Tsu phase俟Thus, the curability of the entire photosensitive resin can be improved. As a result, even if a force is applied at the time of mold release, the inside of the optical component is not destroyed (cohesive failure), and as a result, the mold release property is improved and an optical component free from defects can be obtained. it can. Moreover, production efficiency can be improved by improving the curability of the entire photosensitive resin. In addition, by improving the curability of the photosensitive resin as a whole, it is not necessary to increase the amount of photopolymerization initiator or sensitizer that causes a decrease in the transparency of the optical component, so the transparency of the optical component is also impaired. Absent.

  In particular, when setting the reflectance of light having a wavelength of 365 nm on the mold surface of the molding die to 46% or more is performed by forming the molding die with a material having the reflectance, molding is performed. Since the entire mold can be formed of one material, the mold can be easily manufactured, and the manufacturing cost of the mold can be reduced.

  Moreover, it was formed with the material which has an uneven | corrugated surface and does not have the said reflectance as the said shaping | molding die to set the reflectance of the light of wavelength 365nm to the mold surface of the said shaping | molding die to 46% or more. When performing by using a molding die provided with a coating layer formed of a material having the reflectance along the irregularities on the irregular surface of the mold body, the reflectance is applied only to the coating layer. Therefore, there is a great degree of freedom in selecting the material of the mold body, and a mold body formed of a material optimal for the manufacturing conditions of the optical component to be manufactured can be used.

  In addition, setting the reflectance of light having a wavelength of 365 nm on the mold surface of the mold to 46% or more is a light-transmitting material that has an uneven surface and does not have the reflectance. When the mold body is formed by using a mold having a coating layer formed of the material having the reflectance on the surface opposite to the uneven surface of the formed mold body, Since it has light transmittance, the state of the internal photosensitive resin can be observed in the molding step, and the photosensitive resin can be adjusted to a more appropriate state. Moreover, since the said coating layer does not contact with the photosensitive resin shape | molded, it is not necessary to consider durability, mixing of the foreign material to a photosensitive resin, etc. Therefore, the degree of freedom in selecting the material for forming the coating layer is large, and a coating layer formed of a material that is optimal for the manufacturing conditions of the optical component to be manufactured can be used.

  In particular, when the material having the reflectance is at least one metal selected from the group consisting of aluminum, silver, titanium, platinum, and gold, it is a metal, so that it has durability and is stable over a long period of time. The reflectance can be maintained.

  Further, when the surface of the mold opposite to the mold surface is covered with the material having the reflectance, the material having the reflectance is at least one selected from the group consisting of white, gold and silver. In the case of a paint of one color, since it is coated with a paint, it can be easily coated.

  When the photosensitive resin is composed mainly of an epoxy resin and contains a photopolymerization initiator, the epoxy resin is a resin having excellent heat resistance and low thermal shrinkage. Excellent stability. Moreover, since it contains a photopolymerization initiator, the curability of the photosensitive resin is high, and the production efficiency can be further increased.

It is sectional drawing which shows typically the optical component obtained by one Embodiment of the manufacturing method of the optical component of this invention. (A)-(e) is explanatory drawing which shows typically one Embodiment of the manufacturing method of the optical component of this invention. It is sectional drawing which shows typically the other form of the shaping | molding die used for the manufacturing method of the said optical component. It is sectional drawing which shows typically the further another form of the shaping | molding die used for the manufacturing method of the said optical component. It is explanatory drawing which shows typically the modification which embosses photosensitive resin with a shaping | molding die. It is explanatory drawing which shows typically the evaluation test method of the mold release property of a shaping | molding die. It is explanatory drawing which shows typically the evaluation test method of curability of the photosensitive resin.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing an optical component obtained by an embodiment of a method for manufacturing an optical component of the present invention. The optical component 1 is made of a cured product of a photosensitive resin, and a plurality (three in FIG. 1) are formed on a light-transmitting substrate 2. Examples of the shape of the optical component 1 include a three-dimensional shape such as a hemispherical shape, a spherical shape, a lens shape, a cubic shape, a rectangular parallelepiped shape, a prismatic shape, a cylindrical shape, a spherical shape, a curved surface shape, a pyramid shape, and a conical shape. It is done.

  An embodiment of a method for producing an optical component of the present invention for producing such a three-dimensional optical component 1 will be described for each step.

[Preparation process]
First, as shown in FIG. 2 (a), an unexposed photosensitive resin 1A (see FIG. 2 (b)), which is a material for forming the optical component 1 [see FIG. 2 (e)], and the photosensitive resin A light transmissive substrate 2 to which 1A is supplied and a mold 3 for embossing the photosensitive resin 1A on the light transmissive substrate 2 are prepared. The mold surface (lower surface) 3a of the molding die 3 is a concavo-convex surface for transfer in which a recess 3b is formed by pressing the photosensitive resin 1A to make the photosensitive resin 1A into a desired three-dimensional optical component 1.

  In this embodiment, the mold 3 is made of a material having a reflectance of light having a wavelength of 365 nm of 46% or more. Examples of the material having the reflectance include metals such as aluminum, stainless steel, silver, titanium, platinum, and gold, and white plastic. These may be used alone or in combination of two or more. Of these, aluminum and silver are preferable from the viewpoint of durability. Examples of a method for producing the mold 3 include a casting method, a method of cutting a block body made of the metal, and the like. In the mold 3 made of the above material, the reflectance of light having a wavelength of 365 nm on the mold surface 3a is also 46% or more. The reflectivity at the mold surface 3a of the mold 3 in this embodiment is such that the mold surface 3a with respect to a light beam having a wavelength of 365 nm emitted from the mold surface 3a side of the mold 3 toward the mold surface 3a. It is the ratio of the luminous flux of the light reflected from the surface. The use of the mold 3 having such reflectance is a major feature of the present invention. The reflectance can be measured using, for example, a reflectance measuring machine (manufactured by Jasco, UV-vis, V-670).

  The photosensitive resin 1A includes a resin component such as an epoxy resin and an additive such as a photopolymerization initiator. The addition amount of the additive is within the range of 5 to 8% by weight of the photopolymerization initiator in the photosensitive resin. Examples of the resin component of the photosensitive resin 1A include an acrylic resin, an acrylic urethane resin, and a silicone resin in addition to the epoxy resin. These may be used alone or in combination of two or more. Among these, an epoxy resin is preferable from the viewpoint of excellent heat resistance and heat shrinkability. Moreover, as said additive, in addition to the said photoinitiator, you may use a sensitizer etc. together as needed.

  Examples of the material for forming the light transmissive substrate 2 include glass and resin. Examples of the glass include white plate glass, quartz glass, Pyrex (registered trademark) glass, BK-7, and blue plate glass. Examples of the resin include polyolefin, thermosetting resin, and photosensitive resin. Among them, examples of the polyolefin include polyethylene, polypropylene, polystyrene, polymethyl methacrylate, and polyethylene terephthalate. Examples of the thermosetting resin and photosensitive resin include those mainly composed of epoxy resin, polyimide resin, acrylic resin, silicone resin, and the like. These may be used alone or in combination of two or more. Of these, white plate glass is preferable from the viewpoints of versatility, transparency, and heat resistance.

[Photosensitive resin supply process]
After preparing the photosensitive resin 1A, the light transmissive substrate 2 and the molding die 3 as described above, the photosensitive resin (liquid state) is formed on the light transmissive substrate 2 as shown in FIG. (Or paste) 1A is potted (supplied) using a potting device or the like. The photosensitive resin 1A potted on the light transmissive substrate 2 becomes a dome-shaped layer due to its own surface tension.

[Embossing process]
Next, as shown in FIG. 2 (c), the mold 3 is pressed against the light transmissive substrate 2 with the mold surface 3 a of the mold 3 facing the surface of the light transmissive substrate 2 (embossing). To do). In this embodiment, the mold surface 3 a of the mold 3 is brought into close contact with the surface of the light transmissive substrate 2. As a result, the photosensitive resin 1A on the light-transmitting substrate 2 enters and fills the recess 3b of the mold surface 3a of the mold 3, and the dome-shaped layer of the photosensitive resin 1A becomes the recess 3b of the mold 3. It is formed into a shape.

[Light irradiation process]
Then, as shown in FIG. 2 (d), the photosensitive resin 1 </ b> A is irradiated with light L through the light transmissive substrate 2. At this time, since the surface of the mold surface 3a of the mold 3 is set to the specific reflectance, the irradiated light L passes through the photosensitive resin 1A, and then the mold of the mold 3 The reflected light L reflected from the surface 3a passes through the photosensitive resin 1A again in a state having an energy amount corresponding to the reflectance. That is, not only the irradiated direct light L but also the reflected light L can be used for curing the photosensitive resin 1A. For this reason, the energy of the direct light L gradually decreases as the distance from the light transmissive substrate 2 increases, but the reflected light L compensates for the weakened energy or more and improves the curability of the entire photosensitive resin 1A. Let Thereby, 1 A of photosensitive resin is fully hardened entirely, and the mold release property in the case of a subsequent mold release improves. Thus, when the photosensitive resin 1A is exposed, the mold 3 having the specific reflectance is used as the mold 3 for embossing the photosensitive resin 1A to improve the curability of the photosensitive resin 1A. This is a major feature of the present invention.

  As the light source of the light L to be irradiated, a light source having a peak at a wavelength of 365 nm is used, and examples thereof include a mercury lamp, a xenon lamp, and an LED lamp having an emission wavelength in the 350 to 465 nm region. Among these, a mercury lamp that emits ultraviolet rays having a high energy and a short wavelength is particularly preferable, and an LED lamp and the like are preferable from the viewpoint of reducing environmental load and power consumption.

[Release process]
Next, as shown in FIG. 2E, the mold 3 is released from the cured body of the photosensitive resin 1A [see FIG. 2D]. Thereby, a three-dimensional optical component 1 such as an optical lens formed on the surface of the light transmissive substrate 2 is obtained. At this time, since the photosensitive resin 1A is sufficiently cured as a whole in the exposure process of the photosensitive resin 1A in the previous process, the inside of the optical component 1 is destroyed even if a force is applied during the mold release. There is no such thing as (cohesive failure), and as a result, excellent releasability is achieved.

  In the above embodiment, as the molding die 3 which is a major feature of the present invention, the entire mold is made of a material having a reflectance of light having a wavelength of 365 nm of 46% or more. As what produces (the improvement of the sclerosis | hardenability of 1 A of photosensitive resins, the mold release improvement of the shaping | molding die 3), the thing of the other form shown to FIG. 3 and FIG. 4 can also be used, for example.

  Among them, the mold 4 shown in FIG. 3 has a mold body 41 having a concavo-convex surface corresponding to a desired transfer mold surface 4a, and the surface of the concavo-convex surface of the mold body 41 along the concavo-convex surface. And a coating layer 42 formed as a coating. And the surface of the coating layer 42 becomes the mold surface 4a. The forming material of the mold main body 41 is a material that does not have the reflectance described above, and may be a transparent material or an opaque material, and examples thereof include glass and resin. Examples of a method for producing the molding die body 41 include a molding method, a method of cutting a block body made of the above material, and the like. The material for forming the coating layer 42 is a material having the reflectance described above, and examples thereof include metals such as aluminum, stainless steel, silver, titanium, platinum, and gold. Examples of the method for forming the coating layer 42 include physical vapor deposition methods (PVD methods) such as sputtering methods and vacuum deposition methods, chemical vapor deposition methods (CVD methods), and plating methods.

  Even when the mold 4 shown in FIG. 3 is used at the time of exposure of the photosensitive resin 1A [see FIG. 2 (d)], the reflection of the irradiated light L is similar to that of the embodiment described above in that the mold surface 4a (covering layer) 42 surface). Therefore, the reflectance at the mold surface 4a of the mold 4 shown in FIG. 3 is also similar to the above-described embodiment, with respect to the light beam having a wavelength of 365 nm emitted from the mold surface 4a side toward the mold surface 4a. This is the ratio of the light flux reflected by the surface of the mold surface 4a.

  On the other hand, the mold 5 shown in FIG. 4 includes a mold body 51 having a mold surface 5a and a coating layer 52 formed on the surface of the mold body 51 opposite to the mold surface 5a. I have. The forming material of the mold main body 51 is a light-transmitting material having no reflectivity, and examples thereof include quartz glass, Pyrex (registered trademark) glass, white plate glass, and other resins, and polyolefin resins. . Of these, quartz glass and polydimethylsiloxane (PDMS) are preferable from the viewpoints of transparency and durability. In particular, the PDMS is more preferable because it has excellent releasability because it has a low adhesive property with the photosensitive resin 1A to be molded [see FIG. 2 (d)]. Examples of a method for producing the molding die body 51 include a molding method, a method of cutting a block body made of the above material, and the like. As a forming material and a forming method of the covering layer 52, a method of forming a metal such as aluminum having the reflectance by a PVD method or the like (a forming method similar to the covering layer 42 shown in FIG. 3), or the reflectance Or a method of placing a sheet or plate made of a metal such as aluminum or a method of applying a coating material having the above reflectance such as white, gold or silver.

  When the mold 5 shown in FIG. 4 is used at the time of exposure of the photosensitive resin 1A, the irradiated light L enters the mold body 51 from the mold surface 5a, and then the mold layer body 51 of the coating layer 52 and The light is reflected by the contact surface, passes through the mold body 51 again, and exits from the mold surface 5a. Therefore, the reflectance at the mold surface 5a of the mold 5 shown in FIG. 4 is reflected by the coating layer 52 with respect to a light beam having a wavelength of 365 nm emitted from the mold surface 5a toward the mold surface 5a. It is the ratio of the luminous flux of light that is emitted from the mold surface 5a later.

  In the above embodiment, prior to potting the photosensitive resin 1A on the surface of the light transmissive substrate 2, in order to improve the adhesion between the surface of the light transmissive substrate 2 and the photosensitive resin 1A, The surface of the light transmissive substrate 2 may be treated using various primers such as a coupling agent. By this surface treatment, the surface of the light-transmitting substrate 2 and the cured body of the photosensitive resin 1A can be released from each other, so that the cured body of the photosensitive resin 1A and the molding dies 3, 4, 5 can be removed. The mold releasability is further improved.

  In the above embodiment, as shown in FIG. 2C, when the photosensitive resin 1 </ b> A is embossed with the mold 3, the mold surface 3 a of the mold 3 is in close contact with the surface of the light transmissive substrate 2. However, as shown in FIG. 5, the molding die 3 is pressed so that the mold surface 3a of the molding die 3 does not adhere to the surface of the light-transmitting substrate 2, and the surface portion of the layer of the photosensitive resin 1A is pressed. Alternatively, the shape of the mold surface 3a of the mold 3 may be transferred and cured to manufacture a three-dimensional optical component in which convex portions are formed on the surface of the flat plate-like body. The same applies when the molds 4 and 5 shown in FIGS. 3 and 4 are used.

  Next, examples will be described together with comparative examples. However, the present invention is not limited to the examples.

  The following photosensitive resins (A) to (C) were prepared for evaluating the mold release property and the curability of the photosensitive resin.

[Photosensitive resin (A)]
50 g of bisphenol A type epoxy resin (Japan Epoxy Resin, Epicoat 828), 50 g of alicyclic epoxy resin (CEL-2021P, manufactured by Daicel Chemical Industries, Ltd.), 4 g of curing agent (Adeka Corp., Adeka Optomer SP-170) Was stirred and mixed at 50 ° C. for 10 minutes to prepare a photosensitive resin (A), and then allowed to stand until it fell below 25 ° C. The photosensitive resin (A) had a viscosity of 1147 mPa · s at 25 ° C.

[Photosensitive resin (B)]
In the photosensitive resin (A), a photosensitive resin (B) was prepared by adding 1 g of a curing agent. Other than that was carried out similarly to the said photosensitive resin (A). The photosensitive resin (B) had a viscosity at 25 ° C. of 1219 mPa · s.

[Photosensitive resin (C)]
In the photosensitive resin (A), a resin obtained by replacing 50 g of bisphenol A type epoxy resin with 50 g of bisphenol F type epoxy resin (Japan Epoxy Resin, Epicoat 806) was used as photosensitive resin (C). Other than that was carried out similarly to the said photosensitive resin (A). The photosensitive resin (C) had a viscosity at 25 ° C. of 706 mPa · s.

  And using the said photosensitive resin (A)-(C), the mold release property of the shaping | molding die and the sclerosis | hardenability of the photosensitive resin were evaluated as follows. The results for releasability are shown in Tables 1 to 3 below, and the results for curability are shown in Table 4.

[Evaluation of releasability (measurement of adhesive strength) and evaluation of curability (in fracture mode)]
In the evaluation test method shown in FIG. 6, the difference in the releasability (adhesive strength with the glass plate 62) of the cured body of the photosensitive resin 1A from the glass plate 62 due to the difference in the reflectance of the underlay 61 is as follows. Evaluation was performed as described above. The evaluation test method shown in FIG. 6 corresponds to the case of manufacturing an optical component using the mold 5 shown in FIG.

  That is, first, five types having different reflectivities were prepared as the light reflecting underlay 61 (corresponding to the covering layer 52 of the mold 5 shown in FIG. 4). Each underlay 61 is made of aluminum, stainless steel foil, stainless steel, copper foil, or black paper. Then, as shown in FIG. 6, a light transmissive glass plate (manufactured by SCHOTT, D-263, thickness 0.55 mm) 62 was placed on the upper surface of each underlay 61. In this state, the reflectance of light having a wavelength of 365 nm on the upper surface 62a of the glass plate 62 (corresponding to the mold surface 5a of the mold 5 shown in FIG. 4) is 70.0 when the aluminum underlay 61 is used. % (Examples 1, 4 and 7), 47.5% using the stainless steel underlay 61 (Examples 2, 5 and 8) and 46.0% using the stainless steel underlay 61 (Examples 3, 6, and 9), 35.0% using copper foil underlay 61 (Comparative Examples 1, 3, and 5), 4.0% using black paper underlay 61 (Comparative Examples 2, 4, 6). In addition, the reflectance measuring machine (The Jasco company make, UV-vis, V-670) was used for the measurement of this reflectance. Further, the reflectance varies by about 1 to 2% in the oxidized state of the surface of the underlay 61.

  Next, a silicone resin mold 63 was prepared in which six cylindrical through holes 63a having a diameter of 2 mm were formed in the thickness direction of a silicone resin plate (length 2 cm × width 1 cm × thickness 200 μm). Then, the silicone resin mold 63 was brought into close contact with the upper surface 62 a of the glass plate 62. As a result, the lower end of the through hole 63a was closed with the upper surface 62a of the glass plate 62, and a recess 64 composed of the through hole 63a and the upper surface 62a of the glass plate 62 was formed. Thereafter, each concave portion 64 was filled with one of the photosensitive resins (A) to (C).

Next, a light-transmitting polyethylene terephthalate (PET) film 20 (corresponding to the light-transmitting substrate 2 shown in FIG. 2D) (thickness 50 μm) was adhered to the upper surface of the silicone resin mold 63. And the light L was irradiated from the upper direction of the PET film 20 (irradiation energy 6000mJ / cm < ² >), and the said photosensitive resin 1A was hardened. As a light source for the light L, a UV lamp (manufactured by USHIO, DEEP UV LAMP) was used.

  Thereafter, the PET film 20 and the silicone resin mold 63 were removed to obtain an evaluation test piece in which six columnar cured bodies made of the photosensitive resin 1A were formed on the upper surface 62a of each glass plate 62. .

  Then, using a bump pull tester (Dage 4000, manufactured by Dage), the shear adhesive strength (adhesive force) of the six cured bodies to the glass plate 62 of the evaluation test piece was measured at 25 ° C. The adhesive strengths shown in Tables 1 to 3 below are average values of the shear adhesive strength of the six cured bodies. It shows that it is excellent in the mold release property, so that this adhesive force is small. Moreover, the fracture | rupture forms shown to Tables 1-3 of a postscript are the fracture | rupture forms of the hardening body at the time of measuring the said shear bond strength. When this fracture mode is interfacial fracture, it indicates that the cured body has been neatly peeled off at the interface with the glass plate 62 without cohesive failure, which means that the cured body is cured well. Further, when the destruction mode is cohesive failure, it indicates that the curability of the photosensitive resin 1A is poor and that the resin residue on the glass plate 62 is generated, that is, the cured body is defective.

[Evaluation of curability (by gel time)]
With the evaluation test method shown in FIG. 7, the difference in the curability of the photosensitive resin 1A due to the difference in the reflectance of the rotating plate 71 of the UV rheometer was evaluated as follows. The evaluation test method shown in FIG. 7 corresponds to the case where an optical component is manufactured using the mold 3 shown in FIG. 2A and the case where an optical component is manufactured using the mold 4 shown in FIG. .

Therefore, first, a UV rheometer (manufactured by Rheologica: rotating plate 71 with a diameter of 20 mm) using a mercury lamp (manufactured by Hamamatsu Photonics, LC-8: set so that the illuminance at a wavelength of 365 nm is 20 mW / cm ² ) is used. Use] was prepared. Further, as the rotation plate 71 of the UV rheometer (corresponding to the mold surface 3a of the mold 3 shown in FIG. 2A and the mold surface 4a of the mold 4 shown in FIG. 3), the surface has a wavelength of 365 nm. Three types with different light reflectivities were prepared. Each rotating plate 71 is made of aluminum (reflectance 70.0%: Examples 10 and 12), stainless steel (reflectance 47.5%: Examples 11 and 13), and stainless steel (reflectance 45.0%: Comparative Examples 7 and 8).

  Next, as shown in FIG. 7, one of the photosensitive resins (A) and (B) was potted on the upper surface of the light-transmitting substrate 72 of the UV rheometer. Thereafter, the rotating plate 71 was lowered, and the photosensitive resin 1A was sandwiched between the light-transmitting substrate 72 and the rotating plate 71 so that the photosensitive resin 1A had a set thickness (0.2 mm). In this state, the mercury lamp was irradiated with light, and the light L was irradiated from the lower surface side of the light transmissive substrate 72 to expose the photosensitive resin 1A. Thereby, the viscoelasticity of the photosensitive resin 1A during exposure was measured at 25 ° C., and the time (gel time) from the start of measurement until the elastic term and the viscous term intersected was measured. The gel time is shown in Table 4. It means that it is excellent in sclerosis | hardenability, so that this gel time is short.

  From the results of Table 1 above, the fracture mode is interfacial fracture in Examples 1 to 3, and cohesive fracture in Comparative Examples 1 and 2, so that in Examples 1 to 3, the curability of the photosensitive resin is improved. And it turns out that the defect of the hardening body has not arisen. Moreover, since Examples 1-3 are smaller than the comparative examples 1 and 2, since the adhesive force between a hardening body and the glass plate 62 is small, it turns out that the mold release property is improving. From these facts, it can be seen that setting the reflectance of light having a wavelength of 365 nm to 46% or more on the mold surface of the mold as in the present invention is effective for improving the releasability.

  The comparison between Examples 4 to 6 and Comparative Examples 3 and 4 in Table 2 above, and the comparison between Examples 7 to 9 and Comparative Examples 5 and 6 in Table 3 above are the same as above. I can say that.

  Moreover, from the result of the said Table 4, in Example 10, 11, since the gel time is short compared with the comparative example 7, it turns out that the sclerosis | hardenability of photosensitive resin is improving. From this, it turns out that using the shaping | molding die set to the said reflectance like this invention is effective for the improvement of the sclerosis | hardenability of photosensitive resin. The same can be said for the comparison between Examples 12 and 13 and Comparative Example 8.

  In the above evaluation of releasability (measurement of adhesive force), good results were obtained even when a white coating, a gold coating, or a silver coating was used as the underlay 61.

  Further, in the evaluation of the releasability (measurement of adhesive force), the same result as above was obtained even when the silicone resin mold 63 was directly adhered to the upper surface of the underlay 61 without using the glass plate 62. It was. This case corresponds to the case where an optical component is manufactured using the mold 3 shown in FIG. 2A and the case where an optical component is manufactured using the mold 4 shown in FIG.

  In the evaluation of curability, a glass plate is provided on the lower surface of the rotating plate 71, and the photosensitive resin 1A on the upper surface of the light transmissive substrate 72 is sandwiched between the light transmissive substrate 72 and the glass plate. Even when exposed, similar results were obtained. This case corresponds to the case where an optical component is manufactured using the mold 5 shown in FIG.

  The optical component manufacturing method of the present invention can be used for manufacturing optical components such as optical lenses, optical waveguides, optical fiber cores, and recording layers of optical recording media.

DESCRIPTION OF SYMBOLS 1 Optical component 1A Photosensitive resin 2 Light transmissive substrate 3 Mold 3a Mold surface

Claims (7)

A photosensitive resin is supplied onto the light-transmitting substrate, and the photosensitive resin is embossed with a molding die having an unevenness for transfer corresponding to an optical component on the mold surface. The photosensitive resin is irradiated with light through the light-transmitting substrate below the photosensitive resin, thereby exposing the photosensitive resin, and manufacturing an optical component made of a cured product of the photosensitive resin, at the mold surface of the mold, optics reflectance of the wavelength of 365nm light, by that you set more than 46%, characterized in that so as to improve the releasability of the optical component from the mold surface A manufacturing method for parts.   2. The optical component according to claim 1, wherein the reflectance of light having a wavelength of 365 nm on the mold surface of the mold is set to 46% or more by forming the mold with a material having the reflectance. Manufacturing method.   Setting the reflectance of light having a wavelength of 365 nm on the mold surface of the molding die to be 46% or more is a molding die formed of a material having an uneven surface and not having the reflectance. The manufacturing method of the optical component of Claim 1 performed by using the shaping | molding die which provides the coating layer formed with the material which has the said reflectance along the unevenness | corrugation on the said uneven surface of a main body.   Setting the reflectance of light having a wavelength of 365 nm on the mold surface of the molding die to be 46% or more, the molding die is formed of a light transmissive material having an uneven surface and not having the reflectance. 2. The method of manufacturing an optical component according to claim 1, wherein the molding die body is used by using a molding die provided with a coating layer formed of the material having the reflectance on the surface opposite to the uneven surface. .   The method for manufacturing an optical component according to any one of claims 1 to 4, wherein the material having reflectance is at least one metal selected from the group consisting of aluminum, stainless steel, silver, titanium, platinum, and gold.   5. The method of manufacturing an optical component according to claim 4, wherein the material having reflectance is a paint of at least one color selected from the group consisting of white, gold, and silver.   The manufacturing method of the optical component as described in any one of Claims 1-6 in which the said photosensitive resin has an epoxy resin as a main component and contains the photoinitiator.

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