JP2015194547A - Optical component resin composition and optical components produced using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocurable resin composition for optical components, which is highly transparent and yet offers a high refractive index and superior heat resistance and which is suitable for such applications as an optical lens material and adhesive material between optical components.SOLUTION: An optical component resin composition has a viscosity in a range of 0.1-20 Pa s at 25°C, and a cured product thereof has a refractive index of no less than 1.57 and an Abbe number in a range of 20-40.

Description

  The present invention is a transparent resin for optical applications, has high transparency that allows optical signals to pass through with low loss, and has excellent transparency and heat resistance. The present invention relates to a photocurable resin composition suitable for component materials and the like, and an optical component using the same.

  An imaging device used in recent optical components such as a mobile phone and a digital camera is equipped with an optical lens for imaging. Generally, optical glass or transparent plastic material is used as a lens material. In particular, with the increasing penetration of mobile phones with imaging functions in recent years, it is necessary to manufacture optical lenses at a lower cost. Therefore, polyolefin materials are made of plastic lens materials because of optical transparency and ease of lens design. It has become mainstream. On the other hand, mounting of an image pickup device on a printed circuit board has generally been a pin insertion type using a socket, or a method in which a lens unit is attached to an image sensor after mounting the image sensor on a printed circuit board by solder reflow. However, there is a strong demand for solder reflow mounting of the imaging device itself on a printed circuit board for the purpose of cheaper mass production.

  However, when the imaging device itself is mounted on a printed circuit board by the solder reflow method, the above-described plastic lens is exposed to a high temperature environment above the softening point, which causes problems such as softening and dimensional deformation. . Therefore, in order to solve such a problem, a resin composition mainly composed of an epoxy resin having high heat resistance has been studied as a material for optical components such as optical lenses. For example, an imprint method using a photocurable resin that is a heat-resistant resin is being put into practical use. This imprint method applies a specific fine pattern or unevenness by pressing a molding die against a resin material. There is a method of forming a shape (for example, Patent Document 1).

  Recently, a resin material having a higher refractive index has been demanded as an optical lens is made thinner and higher in resolution. In order to increase the refractive index of the resin composition, it is necessary to use a raw material having a high refractive index, for example, a material having a benzene ring in the skeleton is generally known to have a high refractive index, Although it is useful for increasing the refractive index, it is known that, on the contrary, the transparency is lowered due to the light absorption of the aromatic ring, and the heat discoloration is poor. In general, since high refractive materials have a rigid structure, most materials are solid at room temperature and have a high melting point. For example, fluorene skeleton epoxy resins known as high refractive index materials have been studied in various ways. However, since they are solid at room temperature and the viscosity of the material is high even after melting, the resin increases with the increase in the amount added due to higher refractive index. There is a concern that the viscosity becomes high and the handling property is deteriorated. Similarly, biphenyl skeleton epoxy resins having a glycidyl group at the para position, which are generally used, are also solid at room temperature and have a high melting point. is there. In response to this, countermeasures have been taken by blending a solvent blend or a liquid epoxy resin (Patent Documents 2 and 3).

Japanese Patent No. 3926380 JP2012-129010A JP 2011-225773 A

  As described above, in the prior art, when the refractive index of the resin is increased, there is a problem that the viscosity is increased and the handling property is insufficient, and a problem that high transparency cannot be obtained.

  The present invention has been made in view of such circumstances, and has a high refractive index after curing, which is suitable as an optical component material having excellent handling properties and high transparency and excellent heat resistance. It is an object of the present invention to provide a resin composition for optical parts that can be used and an optical part using the same.

  In order to achieve the above object, the present invention has a viscosity of the resin composition for optical parts at 25 ° C. in the range of 0.1 to 20 Pa · s, and the refractive index of the cured product of the resin composition for optical parts is 1. The first gist is a resin composition for optical parts having an Abbe number of 20 to 40 in the range of .57 or more.

  Moreover, this invention makes the 2nd summary the optical component which consists of a hardening body of the resin composition for optical components which concerns on the said 1st summary.

  As a result of intensive investigations to obtain a resin composition for optical parts having a high refractive index and excellent heat resistance, the present inventors have determined that the viscosity of the resin composition before curing, the curing of the resin composition, Paying attention to the refractive index and Abbe number of the object, experiments were repeated for these preferred ranges. As a result, the viscosity at 25 ° C. of the resin composition for optical parts is in the range of 0.1 to 20 Pa · s, the refractive index of the cured product of the resin composition for optical parts is 1.57 or more, and the Abbe number is It has been found that the intended purpose can be achieved by the resin composition for optical parts in the range of 20 to 40, and the present invention has been achieved. Furthermore, since the resin composition for optical parts of the present invention can be used in a solvent-free system, it can be said that it does not generate voids or the like during molding and is good for use as an optical part.

  As described above, the resin composition for optical parts of the present invention has excellent handling properties and the like without using an organic solvent as described above because the viscosity at 25 ° C. is in the range of 0.1 to 20 Pa · s. Since both of them exhibit the above viscosity, the problem that the organic solvent volatilizes during the photocuring and molding and a void is generated in the cured product can be solved. Thus, since the resin composition for optical components of the present invention can be photocured on a transparent substrate such as a glass plate, a high-quality hybrid lens can be produced by integrating with the transparent substrate. It is. Moreover, since the cured product of the resin composition for optical components has a high refractive index and a low Abbe, it has high transparency, can suppress heat discoloration, and improves optical design in a thin film. Moreover, it is also possible to manufacture as a plastic lens having high heat resistance, for example, by curing with the resin composition for optical parts used alone. Therefore, when the resin composition for an optical component of the present invention is used for a molding material for an optical component such as a lens and a photo-curing adhesive for fixing the optical component, a highly reliable optical product can be obtained. Because it is useful.

  Moreover, when the resin composition for optical components of the present invention contains an epoxy resin represented by the following general formula (1), an effect as a viscosity adjusting component that lowers the viscosity can be expected while being highly refraction. become.

  Further, when a fluorene type epoxy resin having a refractive index of 1.60 or more is used in combination, the refractive index becomes higher.

  Next, embodiments of the present invention will be described in detail. However, the present invention is not limited to this embodiment.

<< Resin composition for optical parts >>
The resin composition for optical parts of the present invention (hereinafter sometimes simply referred to as “resin composition”) has a viscosity at 25 ° C. of the resin composition before curing in the range of 0.1 to 20 Pa · s, The refractive index of the cured product of the resin composition is 1.57 or more, and the Abbe number is in the range of 20-40. The physical properties such as viscosity will be described later.

  The resin composition for an optical component of the present invention having such physical properties can be obtained by appropriately combining, for example, various epoxy resins, a curing agent for epoxy resins, other additives (such as oxetane resins) and the like. And the resin composition for optical components of this invention can be used by a solventless system as above-mentioned.

  Hereinafter, various components will be described in order.

<Epoxy resin>
The epoxy resin can be appropriately selected from various epoxy resins from the viewpoint of desired viscosity, refractive index, and photocurability, but has a fluorene skeleton, a biphenyl skeleton, and a naphthalene skeleton for high bending. An epoxy resin, a bisphenol type epoxy resin, or the like is used.

  In particular, as an epoxy resin that can be expected to have an effect as a viscosity adjusting component that lowers the viscosity while having a high refraction, a biphenyl skeleton epoxy resin having a glycidyl group at the ortho position of the benzene ring is preferable. An epoxy resin represented by the general formula (1) is given. These may be used alone or in combination of two or more.

In the above formula (1), a particularly preferred embodiment is when R _{1 to} R ₈ are all H (hydrogen atom).

  The epoxy resin represented by the general formula (1) preferably has an epoxy equivalent in the range of 100 to 500.

  The epoxy resin represented by the general formula (1) preferably has a refractive index of 1.57 or more and a melting point of 90 ° C. or less, particularly preferably a refractive index of 1.58 or more and a melting point. It is 85 degrees C or less.

  Specific examples of the epoxy resin represented by the general formula (1) include OPP-G manufactured by Sanko Co., Ltd.

  The content of the epoxy resin represented by the general formula (1) is preferably 5 to 75% by weight, particularly preferably 10 to 70% by weight, based on the total resin components in the optical component resin composition. It is. That is, if the content is too small, it may be difficult to obtain a target low-viscosity and high-refractive resin composition. If the content is too large, the brittleness of the resin composition tends to decrease. Because it is seen.

  Furthermore, in order to increase the refractive index, it is preferable to use a fluorene type epoxy resin in combination. The fluorene type epoxy resin may be an epoxy resin having a fluorene skeleton, and various fluorene type epoxy resins can be appropriately selected from the viewpoint of desired viscosity, refractive index, and photocurability. Specific examples include PG-100 and EG-200 manufactured by Osaka Gas Chemical Company. These may be used alone or in combination of two or more.

  The content of the fluorene type epoxy resin is preferably less than 60% by weight, particularly preferably less than 50% by weight, based on the total resin component in the resin composition for optical components. That is, if the content is too large, the viscosity tends to be high and the handling property tends to be lacking.

  The fluorene type epoxy resin preferably has a refractive index of 1.60 or more, and particularly preferably has a refractive index of 1.62 or more.

  In addition, from the viewpoint of improving handling properties and reliability, within the range satisfying a desired refractive index, monofunctional or bifunctional epoxy resins other than the epoxy resin represented by the general formula (1) and the fluorene type epoxy resin, etc. Can also be blended. Examples of the epoxy resin include alicyclic epoxy and hydrogenated bisphenol type epoxy resin, and bisphenol A type epoxy resin and bisphenol F type epoxy resin are preferably used particularly for the purpose of increasing the refractive index. .

<Curing agent for epoxy resin>
As the curing agent for the epoxy resin, a curing agent that promotes the polymerization reaction of the epoxy resin such as a photopolymerization initiator, a thermal acid generator, an imidazole-based curing catalyst, or a curing aid is appropriately used depending on the application. used. For example, in the case of a photopolymerization initiator, any photopolymerization initiator may be used as long as it can initiate cationic polymerization. For example, the photopolymerization initiator is formed of an anionic component made of antimony or phosphorus and a cationic component such as sulfonium, iodonium, or phosphonium. Onium salts can be used. Specifically, aromatic sulfonium salts, aromatic iodonium salts, aromatic phosphonium salts, aromatic sulfoxonium salts, and the like can be used. Of these, aromatic sulfonium salts are preferred from the viewpoint of photocurability.

  For example, in the case of a photopolymerization initiator, the content of the epoxy resin curing agent is preferably set to 0.05 to 3 parts by weight with respect to 100 parts by weight of the resin component of the optical component resin composition. Particularly preferred is 0.05 to 2 parts by weight. That is, if the content is too small, the curability tends to deteriorate, and if it is too large, the curability is improved but the transparency of the cured product tends to be impaired.

<Other additives>
An oxetane resin can be added to the resin composition for an optical component of the present invention from the viewpoint of improving handling properties and curability. As the oxetane compound, an oxetane compound having one or more oxetane rings per molecule is used. For example, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, di [2- (3-oxetanyl) butyl] ether, 3-ethyl-3-hydroxymethyloxetane, xylylene bis Oxetane, 3-ethyl-3 {[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane, 3-ethyl-3- (phenoxymethyl) oxetane, 4,4'-bis [(3-ethyl-3 -Oxetanyl) methoxymethyl] biphenyl, 1,4-bis [(3-ethyloxetane-3-yl) methoxy] benzene, 1,3-bis [(3-ethyloxetane-3-yl) methoxy] benzene, 1, 2-bis [(3-ethyloxetane-3-yl) methoxy] benzene, 4,4′-bis [(3-ethyloxetane-3-yl) methoxy Biphenyl, 2,2′-bis [(3-ethyl-3-oxetanyl) methoxy] biphenyl, 3,3 ′, 5,5′-tetramethyl [4,4′-bis (3-ethyloxetan-3-yl) ) Methoxy] biphenyl, 2,7-bis [(3-ethyloxetane-3-yl) methoxy] naphthalene, 1,6-bis [(3-ethyloxetane-3-yl) methoxy] -2,2,3 3,4,4,5,5-octafluorohexane, 3 (4), 8 (9) -bis [(1-ethyl-3-oxetanyl) methoxy] methyl-tricyclo [5,2,1,2,6 ] Decane, 1,2-bis {[2- (1-ethyl-3-oxetanyl) methoxy] ethylthio} ethane, 4,4′-bis [(1-ethyl-3-oxetanyl) methyl] thiodibenzenethioether, 2,3-bis [(3 Ethyloxetane-3-yl) methoxymethyl] norbornane, 2-ethyl-2-[(3-ethyloxetane-3-yl) methoxymethyl] -1,3-o-bis [(1-ethyl-3-oxetanyl) Methyl] -propane-1,3-diol, 2,2-dimethyl-1,3-o-bis [(3-ethyloxetane-3-yl) methyl] -propane-1,3-diol, 2-butyl- 2-ethyl-1,3-o-bis [(3-ethyloxetane-3-yl) methyl] -propane-1,3-diol, 1,4-o-bis [(3-ethyloxetane-3-yl ) Methyl] -butane-1,4-diol, 2,4,6-o-tris [(3-ethyloxetane-3-yl) methyl] cyanuric acid and the like. These may be used alone or in combination of two or more.

  The content of the oxetane compound is preferably set to 5 to 40% by weight with respect to the total resin components in the optical component resin composition. That is, when there is too much content, the tendency for it to become difficult to obtain the desired high refractive index will be seen.

  The resin composition for optical parts of the present invention can be blended with a photosensitizer such as anthracene or an acid multiplier for the purpose of enhancing curability. Furthermore, in the use which produces hardened | cured material on base materials, such as glass, in order to improve adhesiveness with a base material, you may add a silane type or a titanium type coupling agent. In addition, as other components, flexibility imparting agents such as synthetic rubbers and silicone compounds, and additives such as antioxidants, antifoaming agents, various pigments, dyes, inorganic fillers, and the like are appropriately blended as necessary. can do. On the other hand, addition of an organic solvent or the like for the purpose of improving handling properties is not preferable from the viewpoint of generation of voids during molding and deterioration of characteristics, and it is preferably designed as a solventless system.

  The resin composition for an optical component of the present invention includes, for example, an epoxy resin represented by the general formula (1) and an epoxy resin such as a fluorene type epoxy resin, a curing agent for the epoxy resin, and other if necessary. These additives (oxetane compounds and the like) can be blended at a predetermined ratio and heated and melt mixed.

  The resin composition for optical parts of the present invention thus obtained has all the following physical properties (1) to (3), which is a feature of the present invention.

(1) Viscosity The resin composition for optical components of the present invention has a viscosity at 25 ° C. of 0.1 to 20 Pa · s, preferably 0.1 to 18 Pa · s. That is, if the viscosity is too low, it is difficult to control the amount of the solution when dropping, for example, by an ink jet method, and if the viscosity is too high, the handling property is inferior.

  The viscosity of the resin composition for optical parts is measured, for example, by using a standard rotor (1 ° 34 ′ × R24) with an E80 type viscometer (RE-80U) manufactured by Toki Sangyo Co., Ltd. Can be measured.

(2) Refractive index In the resin composition for optical components of the present invention, the cured product has a refractive index of 1.57 or more, preferably in the range of 1.59 to 1.64. That is, if the refractive index of the cured product is too low, for example, when forming an optical lens or the like for a mobile device or the like, the lens becomes thick, which may make it difficult to reduce the height of the camera module.

The refractive index of the cured product is, for example, by pouring a resin composition (liquid resin) for optical components into a transparent mold having a predetermined size (for example, 1 × 1.5 × 0.5 cm), and ultraviolet (UV). After being irradiated and cured (for example, 10,000 mJ / cm ² ), it is removed from the mold and subjected to heat treatment under predetermined conditions (for example, 150 ° C. × 1 hour). After polishing the surface of the molded product thus obtained using a grinder, the refractive index in a 25 ° C. environment can be measured using a refractometer (manufactured by Atago Co., Ltd.).

(3) Abbe number As for the resin composition for optical components of this invention, the Abbe number of hardened | cured material is the range of 20-40, Preferably it is the range of 20-35. That is, if the Abbe number of the cured product is too small, the wavelength dependency of the resulting cured product increases, and there are concerns such as color bleeding depending on the application.

In the present invention, the Abbe number refers to the reverse dispersion ability in an optical component (cured body) such as a so-called optical lens. According to JIS Z 8120, for example, a cured body of a resin composition for optical components ( It is a value measured by an Abbe refractometer at 25 ± 10 ° C. using a test piece) and calculated by the following mathematical formula (x).
Abbe number = ([refractive index at 589 nm] −1) / ([refractive index at 486 nm] − [refractive index at 656 nm]) (x)

  The Abbe number of the cured product can be measured using, for example, a refractometer (for example, manufactured by Atago Co., Ltd.) after polishing the surface of the cured product (such as an optical component) with a grinder.

  Furthermore, the resin composition for optical parts of the present invention preferably has a viscosity at 40 ° C. in the range of 0.05 to 5.0 Pa · s, more preferably in the range of 0.05 to 4.5 Pa · s. is there. That is, when the viscosity is too low, for example, in the case of an ink jet method, the liquid amount tends to be difficult to control, and when the viscosity is too high, the handling property tends to be inferior.

  In the resin composition for optical parts of the present invention, the transmittance of the cured product at a wavelength of 400 nm is preferably 80% or more, more preferably 83% or more. That is, when the transmittance is too low, the transparency tends to be inferior.

  The resin composition for optical parts of the present invention is used, for example, as follows. That is, the resin composition is potted on a transparent substrate such as glass, and a desired molding die is pressed onto the resin composition to fill the resin composition into the molding die, and light is irradiated there. It can be cured by doing so. Then, by removing the molding die from the molding die, a cured body (molded product) of the resin composition integrated on the transparent substrate can be obtained. Alternatively, the resin composition can be filled into a transparent mold that transmits light and photocured. The resin composition for optical parts of the present invention can produce, for example, a hybrid lens by such a production method. Moreover, the resin composition for optical components of the present invention can be cured by itself in a molding die to be an optical component such as an optical lens. The molded body (cured body) thus obtained may be removed from the mold and further subjected to heat treatment at a predetermined temperature as necessary. By the heating, the heat resistance stability of the cured product can be enhanced, and particularly in the case of a laminate with a transparent substrate, the adhesion between the substrate and the cured resin product can be enhanced.

For the light irradiation, for example, a UV lamp or a single band lamp having a specific wavelength can be used as an apparatus, and a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, or the like can be used as a light source. it can. As an irradiation amount, 2000-200000 mJ / cm < ² > is preferable. That is, if the irradiation amount is less than the above range, the desired cured product shape may not be obtained on the substrate due to insufficient curing, and if it exceeds the above range, photodegradation occurs due to excessive irradiation, and thereafter This is because it may be colored by heat treatment or the like, and transparency may be impaired. Moreover, as conditions for the heat treatment after the light irradiation, a temperature of 80 to 170 ° C. is preferably about 1 hour.

  In addition, the resin composition for optical components of this invention can also be shape | molded in a sheet form irrespective of the above shaping | molding molds.

  And the resin composition for optical components of the present invention obtained as described above has the effect that the mechanical properties that are small in discoloration and stable against thermal stress are obtained even by heat during solder reflow. Therefore, it can be advantageously used when parts and the like mounted with the cured product of the present invention are collectively mounted by solder reflow.

  The resin composition for an optical component of the present invention is used as a molding material (optical component material) for an optical component such as an optical lens by the manufacturing method as described above, and is light-cured for fixing an optical waveguide or an optical component. It can be used for mold adhesives.

  Next, the present invention will be described based on examples. However, the present invention is not limited to these examples. In the examples, “parts” means weight basis unless otherwise specified.

  First, prior to the examples, the following epoxy resins, epoxy resin curing agents, other additives, and the like were prepared.

<Epoxy resin>
[A-1]
In the formula (1), R _{1 to} R ₈ are all H (refractive index 1.59, melting point 50 ° C., epoxy equivalent 226 g / eq).
[A-2]
In the formula (1), R ₅ is a phenyl group and R ₈ is —O—Gly (Gly: glycidyl group), and other R _{1 to} R ₇ are H (refractive index 1.62, melting point 70 ° C., Epoxy equivalent 165 g / eq)
[A-3]
In the formula (1), R ₃ is —O—Gly (Gly: glycidyl group), and other R _{1 to} R ₈ are H (refractive index 1.585, melting point 40 ° C., epoxy equivalent 113 g / eq).

<Curing agent for epoxy resin>
[B-1]
Triarylsulfonium salt photopolymerization initiator (photoacid generator) (50 wt% propylene carbonate solution) in which the anion component is Sb ₆ ⁻ and the cation component is the following structural formula (2)

<Other additives>
[C-1]
Bisphenol A type epoxy resin (epoxy equivalent 175 g / eq, solid (25 ° C.), softening point 45 ° C., refractive index 1.57)
[C-2]
Fluorene type epoxy resin (epoxy equivalent 259 g / eq, refractive index 1.64)
[C-3]
3-ethyl-3-{[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane [c-4]
Silane coupling agent: 3-glycidoxypropylmethyldiethoxysilane [c-5]
9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide [c-6]
Fluorene type epoxy resin (epoxy equivalent 311 g / eq, refractive index 1.68)
[YX4000]
Biphenyl type epoxy resin (Mitsubishi Chemical Corporation)
[YX4000H]
Biphenyl type epoxy resin (Mitsubishi Chemical Corporation)

[Examples 1-8, Comparative Examples 1-5]
Each of the above components were blended in the proportions shown in Table 1 and Table 2 below, followed by heat-melt mixing to produce a resin composition for optical parts.

  Each characteristic evaluation was performed according to the following reference | standard regarding the resin composition for optical components of the Example and comparative example which were obtained in this way. The results are shown in Tables 1 and 2 below.

[Refractive index]
The resin composition for optical parts (liquid resin) is poured into a 1 × 1.5 × 0.5 cm transparent mold, cured by irradiating with ultraviolet (UV) at 10,000 mJ / cm ² , and then removed from the mold. A heat treatment at 1 ° C. for 1 hour was performed. The surface of the molded product thus obtained was polished using a grinder, and then the refractive index in a 25 ° C. environment was measured using a refractometer (manufactured by Atago Co., Ltd.). As a result, the case where the refractive index was less than 1.57 was evaluated as x, and the case where the refractive index was 1.57 or more was evaluated as ◯.

[Abbe number]
Using the refractive index measurement sample, the Abbe number was calculated based on the above formula (x) in the Abbe measurement mode of the same apparatus (manufactured by Atago Co., Ltd.) as the refractive index measurement. As a result, an Abbe number of less than 20 or more than 40 was evaluated as x, and an Abbe number of 20 or more and 40 or less was evaluated as ◯.

[25 ° C viscosity]
The viscosity of the resin composition for optical components in an environment of 25 ° C. was measured with a standard rotor (1 ° 34 ′ × R24) with an E80 viscometer (RE-80U) manufactured by Toki Sangyo Co., Ltd. As a result, the case where the viscosity was less than 0.1 Pa · s or exceeded 20 Pa · s was evaluated as x, and the case where the viscosity was 0.1 Pa · s or more and 20 Pa · s or less was evaluated as ◯.

[40 ° C viscosity]
The viscosity of the resin composition for optical components in an environment of 40 ° C. was measured with a standard rotor (1 ° 34 ′ × R24) with an E80 viscometer (RE-80U) manufactured by Toki Sangyo Co., Ltd. As a result, the case where the viscosity was less than 0.05 Pa · s or exceeded 5 Pa · s was evaluated as x, and the case where the viscosity was 0.05 Pa · s or more and 5 Pa · s or less was evaluated as ◯.

[Heat-resistant discoloration a (transparency)]
Using a resin composition for optical parts, a film is formed on a PET film (Mitsubishi Chemical Polyester Film Co., Ltd., Diafoil MRF-50) that has been subjected to silicone release treatment to a thickness of 300 μm, and this is irradiated with light ( The primary curing was performed by applying 10,000 mJ / cm ² ). Then, 150 degreeC x 1 hour heat processing were performed, and the hardening body (test piece) was obtained. About this test piece, it evaluated using the spectrophotometer (JASCO Corporation), and measured and confirmed the light transmittance of wavelength 400nm. As a result, a light transmittance of less than 70% was evaluated as x, a light transmittance of 70% to less than 80% was evaluated as Δ, and a light transmittance of 80% or more was evaluated as ◯.

[Heat-resistant discoloration b (transparency)]
Using a resin composition for optical parts, a film is formed on a PET film (Mitsubishi Chemical Polyester Film Co., Ltd., Diafoil MRF-50) that has been subjected to silicone release treatment to a thickness of 300 μm, and this is irradiated with light ( The primary curing was performed by applying 10,000 mJ / cm ² ). Then, 150 degreeC x 1 hour heat processing were performed, and the hardening body (test piece) was obtained. The test piece passed through a reflow furnace at 260 ° C. for 10 seconds was evaluated using a spectrophotometer (JASCO Corporation), and the light transmittance at a wavelength of 400 nm was measured and confirmed. As a result, the light transmittance of less than 60% was evaluated as x, the light transmittance of 60% or more and less than 70% as Δ, and the light transmittance as 70% or more as ◯.

  From the above results, the example product having a low viscosity and a high refractive index and a low Abbe obtained better results regarding transparency than the comparative example product. Therefore, by using the resin composition for optical parts of the example product, it becomes possible to provide an optical part such as an optical lens having a high refractive index and excellent heat discoloration. In addition, optical components using this resin composition have stable mechanical properties against heat stress without being discolored by heat during solder reflow. It can be used advantageously.

  On the other hand, the products of Comparative Examples 1 to 3 have a very high viscosity at 25 ° C. and a very high viscosity at 40 ° C., so that the handling properties are inferior. It is clear that Comparative Examples 1 and 2 are particularly unsuitable as optical component materials because of their low transparency. Moreover, since the comparative example 4 product had the high Abbe number of the hardened | cured material, its refractive index was low, and the viscosity in 40 degreeC was too low, there existed difficulty in control at the time of dripping a fixed amount of solutions. The product of Comparative Example 5 is inferior in handling properties because the Abbe number of the cured product is low and the viscosity at 25 ° C. is high. Furthermore, it was confirmed that the product of Comparative Example 5 was difficult to actually use because the resin was clouded only after being placed at room temperature for several hours.

  Since the resin composition for optical parts of the present invention can be a three-dimensional molded article (cured product) having a high refractive index while having high transparency, a molding material for optical parts such as optical lenses (materials for optical parts) ) And optical applications such as a photo-curing adhesive for fixing optical components. Moreover, since the optical component using the resin composition for optical components of the present invention has high reliability, it can be used for optical components (optical products) such as optical lenses.

Claims (7)

  The resin composition for optical components has a viscosity at 25 ° C. of 0.1 to 20 Pa · s, the refractive index of the cured product of the resin composition for optical components is 1.57 or more, and the Abbe number is 20 to 40. A resin composition for optical parts, characterized by being in a range.   The resin composition for an optical component according to claim 1, wherein the resin composition for an optical component has a viscosity at 40 ° C. of 0.05 to 5.0 Pa · s.   The resin composition for optical components according to claim 1 or 2, wherein the cured product of the resin composition for optical components has a transmittance of 80% or more at a wavelength of 400 nm. The resin composition for optical components as described in any one of Claims 1-3 containing the epoxy resin represented by following General formula (1).

  The resin composition for an optical component according to claim 4, wherein the epoxy resin represented by the general formula (1) has a refractive index of 1.57 or more and a melting point of 90 ° C or less.   Furthermore, the resin composition for optical components of Claim 5 containing the fluorene type epoxy resin whose refractive index is 1.60 or more.   The optical component which consists of a hardening body of the resin composition for optical components as described in any one of Claims 1-6.