JP2011235461A - Method for producing plastic lens or optical waveguide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a plastic lens or an optical waveguide which can provide a cured material high in transparency even when its thickness is at least 0.2 mm by an optical imprint method, maintain a high throughput without lowering the illuminance of an exposure machine, sufficiently carry out curing even when a polydimethylsiloxane resin having oxygen permeability is used for a mold material, and can reduce the deterioration of a mold.SOLUTION: In the method for producing the plastic lens or the optical waveguide which is obtained by arranging a light source, the light transmittable mold, and a photosetting resin composition in this order and photo-curing the photosetting resin composition by making it to be irradiated with light through the light transmitting mold, the light transmittable mold has light diffusing properties.

Description

  The present invention relates to a method for producing a plastic lens, for example, an imaging optical lens, an LED lens, and an optical waveguide, using the photocurable resin composition.

As a new technique for forming a fine pattern at a low cost, an imprint technique is being developed, and is disclosed in the following Patent Documents 1 to 4 and the like.
This is because a predetermined pattern is formed by pressing a workpiece against a workpiece using a mold (hereinafter also referred to as a “mold”) in which fine irregularities (mold pattern) such as a lens shape are formed on the surface. Is to be transferred to. This imprint technique is roughly classified into a thermal imprint method and an optical imprint method according to the material of the workpiece.

  In the thermal imprint method, a thermoplastic resin is placed as a resin material to be transferred onto a substrate, and the thermoplastic resin is softened by heating up to a glass transition temperature or higher, and the mold is pressed from above the softened resin. Thus, it is possible to obtain a resin molded member having a concavo-convex shape transferred thereto, but since it takes a long time for heating and cooling, the disadvantage is low throughput and low dimensional accuracy due to thermal expansion and contraction. Yes. On the other hand, since optical imprinting can be molded at a temperature close to room temperature, it is superior to thermal imprinting with high throughput and high accuracy.

  In the photoimprint method, a photocurable resin composition is placed on a substrate as a work material, a mold is pressed on the photocurable resin composition, and the photocurable resin is irradiated with ultraviolet rays (UV). The composition is cured, and a three-dimensional shape (uneven shape) of the mold is transferred to obtain a resin molded member.

JP 2007-186570 A JP 2007-176037 A JP 2007-150053 A JP 2004-34300 A JP-A-6-8252

The optical imprint method can achieve high-precision processing and high throughput, but if a material with a thickness exceeding 0.2 mm is created by the photo-imprint method, the photo-curable resin composition is unevenly cured. As a result, undulations and irregularities can be formed inside the resin, and the transparency of the cured product is reduced. Patent Document 5 discloses that a light diffusing plate is inserted between an exposure light source and a mold in order to eliminate such unevenness caused by photocuring.
However, there are cases where it is difficult to install the light diffusing plate on the apparatus and it may be difficult to install due to the structure of the apparatus. Further, even when it can be easily installed, when the distance between the light diffusing plate and the photocurable resin composition is even a little, the light emitted from the diffusing plate spreads by about 20 to 30% around the air, Due to the presence of the layer, the light diffusing plate and air interface reflection are reduced by about 4%, and the interface reflection between air and the photocurable resin composition is about 4%. There was a problem that the amount of light directly hitting the resin composition was reduced, resulting in a decrease in throughput.

In particular, a photo-curing resin composition that uses oxygen-permeable polydimethylsiloxane (PDMS) resin as a mold material and a photo-curing resin composition as a photo-curing resin composition has a high exposure to prevent oxygen curing. If the amount of light is reduced, the mold will be peeled off while maintaining the tackiness on the mold side of the resulting cured product, and the resulting cured product will have insufficient surface curing. There was also a problem that the deterioration of the product was accelerated.
The present invention solves the above-mentioned conventional problems, can form an optical member having a high transparency with a high throughput, can be sufficiently cured even when a PDMS resin having a high oxygen permeability is used as a molding material, The life of the mold can also be extended.

  In light of the above-described problems of the prior art, the present inventors have conducted extensive studies and repeated experiments. As a result, the light source, the light-transmitting mold, and the photocurable resin composition are arranged in this order and have light diffusibility. It has been found that the above problems can be solved by producing a plastic lens or a diffuser plate using a light-transmitting mold, and the present invention has been completed.

That is, the present invention is as follows.
[1] A plastic lens or light obtained by arranging a light source, a light transmissive mold, and a light curable resin composition in this order, and irradiating light through the light transmissive mold to light cure the light curable resin composition. In the manufacturing method of a waveguide, the manufacturing method of the plastic lens or optical waveguide whose light-transmitting mold has light diffusibility.
[2] The method for producing a plastic lens or optical waveguide according to [1] above, wherein the light transmissive mold has a haze value at 365 nm of 50% or more and a light transmittance at 365 nm of 80% or more.
[3] The light-transmitting mold has a mold pattern with a thickness of 0.2 mm to 5 mm on the surface on the photocurable resin composition side, and has an uneven shape with a thickness of 0.1 μm to 50 μm on the surface on the light source side. The manufacturing method of the plastic lens or optical waveguide as described in said [1] or [2].
[4] The method for producing a plastic lens or optical waveguide according to [3], wherein the uneven shape of 0.1 μm to 50 μm is spherical or hemispherical.
[5] The plastic lens or the light according to any one of [1] to [4], wherein the light transmissive mold is a mold in which fine particles having a refractive index different from that of a mold material are dispersed inside the mold. A method for manufacturing a waveguide.

[6] The method for producing a plastic lens or optical waveguide according to any one of [1] to [5], wherein the light transmissive mold is a mold made of polydimethylsiloxane as a raw material.
[7] The above light-transmitting mold is a mold obtained by laminating a resin having a mold pattern on quartz or glass, and the quartz or glass has light diffusibility, [1] to [5] The manufacturing method of the plastic lens or optical waveguide as described in any one of these.
[8] The method for producing a plastic lens or optical waveguide according to [7], wherein the resin having the mold pattern is polydimethylsiloxane.
[9] The light transmissive mold is a mold obtained by laminating a member having a mold pattern on a support having light diffusibility so that the mold pattern surface is on the outside, and the support and the mold The method for producing a plastic lens or optical waveguide according to any one of the above [1] to [8], wherein a difference in refractive index from a member having a mold pattern is 0.1 or less.
[10] The light transmissive mold is a mold in which quartz or glass is used as a support having light diffusibility, polydimethylsiloxane is used as a member having a mold pattern, and laminated so that no air exists between the two. The method for producing a plastic lens or optical waveguide according to [9] above.

  As described above, according to the present invention, a highly transparent cured product can be obtained even with a thickness of 0.2 mm or more by the optical imprint method, high throughput can be maintained without reducing the illuminance of the exposure machine, and oxygen-permeable PDMS. Even when a resin is used as a molding material, it can be cured sufficiently and the deterioration of the mold can be reduced.

Hereinafter, the manufacturing method of the plastic lens or optical waveguide of the present invention will be described in detail.
In the production method of the present invention, a light source, a light-transmitting mold, and a photocurable resin composition are arranged in this order, and the photocurable resin composition is photocured by irradiating light through the light-transmitting mold. The light transmissive mold has light diffusibility.
The haze value at 365 nm of the light transmissive mold is preferably 50% or more, and the transmittance at 365 nm is preferably 80% or more.
The haze value is preferably 50% or more, and more preferably 60% or more. From the viewpoint of transparency of the obtained cured product (plastic lens or optical waveguide), 50% or more is preferable. The haze value is measured according to JIS K-7136.
The light transmittance at 365 nm of the light transmissive mold is preferably 80% or more, and more preferably 90% or more. From the viewpoint of mechanical properties of the obtained cured product (plastic lens or optical waveguide), the light transmittance is preferably 80% or more. The light transmittance at 365 nm is measured by JIS K-7361-1.

As a method of giving light diffusibility to the light transmissive mold, for example,
1) On the side (light source side) opposite to the uneven surface of the mold (pattern surface, preferably the thickness is 0.2 mm to 5 mm), the thickness is 0.1 μm to 50 μm by a method such as sandblasting or embossing molding. A method of forming an uneven shape,
2) A method of applying a light diffusing agent,
3) A method in which fine particles having a refractive index different from that of the mold material are mixed and dispersed inside the mold,
Etc.

In the method 1), a mold obtained by laminating a resin having a mold pattern on quartz or glass having light diffusibility can be used.
In this case, quartz or glass having light diffusibility is preferable because it can support a resin having a mold pattern (for example, PDMS resin) and can apply a certain pressure during light irradiation. Quartz or glass having light diffusibility can be obtained by forming an uneven shape with a thickness of 0.1 μm to 50 μm on the surface thereof.
Moreover, since the uneven | corrugated shape of thickness 0.1 micrometer-50 micrometers is spherical or hemispherical, since the incident angle with glass becomes larger than a triangular shape, reflection on the surface decreases and it becomes a photocurable resin composition. This is desirable because the amount of incident light can be increased. The thickness of the uneven shape is more preferably 0.5 μm to 10 μm.
Moreover, quartz, glass, and PDMS resin can be used as the material for the light transmissive mold.

In the above method 3), for example, fine particles having a refractive index different from that of the mold material such as PDMS and polymethyl methacrylate (PMMA) may be used. As such fine particle members, inorganic fine particles such as silica, alumina, talc, zirconia, zinc oxide and titanium dioxide, and organic fine particles such as polymethyl methacrylate, polystyrene, polyurethane, benzoguanamine and silicone resin should be used. Can do. The shape of the fine particles is preferably spherical, and the diameter of the particle diameter is preferably 0.1 μm to 20 μm, more preferably 0.1 μm to 10 μm. These fine particles are preferable from the viewpoint of reducing reflection on the surface and increasing the amount of light incident on the photocurable resin composition.
The diameter of the particle diameter is most preferably 0.5 μm to 5 μm from the viewpoint of light transmittance of the mold. Further, in order to prevent the shape of the fine particles from appearing on the surface of the mold in contact with the photocurable resin composition, it is preferable that the transparent concavo-convex mold layer and the layer in which the light diffusing agent is kneaded are made into two layers.

In addition, when using a mold obtained by laminating a member having a concavo-convex surface (mold pattern surface) on a support having light diffusibility so that the concavo-convex surface is on the outside, From the viewpoint of reducing the reflection of light, it is preferable that the mold has a refractive index difference of 0.1 or less between the support having light diffusibility and the member having an uneven surface.
Moreover, it is preferable that an air layer does not exist between the said support body and the member which has an uneven surface.
This is because light that has passed through a support having light diffusibility becomes diffused light. Therefore, if light passes through a layer of air before entering a member having an uneven surface, reflection at the air interface increases and diffused light (Td ) And the straight light (Tt) are reduced and the haze value is lowered, and the entire transmittance is reduced by about 10% due to the presence of the air layer.
From the viewpoint of laminating so as not to form an air layer, the material of the support having light diffusibility is preferably glass or quartz, and the material of the member having an uneven surface is preferably PDMS.

The photocurable resin composition preferably contains a resin having a (meth) acryloyl group and a photopolymerization initiator. As the resin having a (meth) acryloyl group, for example, the following polyorganosiloxane can be used.
The polyorganosiloxane is at least the following general formula (1):
(R ₁ ) _4-n- (Si)-(OR ₂ ) _n (1)
{In the formula, R ₁ is a hydrogen atom, a phenyl group, or a monovalent organic group having 1 to 17 carbon atoms; and R ₂ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a C 1 to 18 carbon atom. It is an organic group, and n is an integer of 1 to 4, and when a plurality of R ₁ and R ₂ are present, they may be the same or different. } Is a condensate made from an organosilane represented by

  The polyorganosiloxane to be stored has a remarkable effect by the storage method of the present invention when an alkoxy group bonded to silane or a hydroxyl group bonded to silane is present, and further when a photopolymerizable group is present. To do.

The polyorganosiloxane having an alkoxy group bonded to silane or a hydroxyl group bonded to silane has at least one silanol compound {in the general formula (1), each of a plurality of R _{1 s} independently has at least one aromatic group. An organic group having 6 to 18 carbon atoms, and R ₂ is a hydrogen atom. } And at least one alkoxysilane compound {wherein R ₁ in the general formula (1) contains at least one group selected from the group consisting of an epoxy group and a carbon-carbon double bond group. R ₁ may be the same or different when there are a plurality of organic groups, R ₂ is each independently a methyl group or an ethyl group, and n is an integer of 2 or 3 is there. } And a catalyst, and polymerized without positively adding water.

  Suitable silanol compounds include diphenyl silane diol, di-p-toluyl silane diol, di-p-styryl silane diol, dinaphthyl silane diol, and the like. In view of copolymerization, heat resistance, etc., diphenyl silane Silane diol (hereinafter also referred to as “DPD”) is particularly suitable.

  Suitable alkoxysilane compounds include 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3- Glycidoxypropyltriethoxysilane, vinylmethyltrimethoxysilane, vinylethyltrimethoxysilane, vinylmethyltriethoxysilane, vinylethyltriethoxysilane, 1-propenyltrimethoxysilane, 1-propenyltriethoxysilane, 2-propenyltri Methoxysilane, 2-propenyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acrylo Cypropyltriethoxysilane, p-styryltrimethoxysilane, p-styryltriethoxysilane, p- (1-propenylphenyl) trimethoxysilane, p- (1-propenylphenyl) triethoxysilane, p- (2-propenyl) Phenyl) trimethoxysilane, p- (2-propenylphenyl) triethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, p- Examples include styrylmethyldimethoxysilane and p-styrylmethyldiethoxysilane.

  Suitable alkoxysilane compounds further include compounds having a photopolymerizable carbon-carbon double bond such as 3-methacryloxypropyltrimethoxysilane, 3- Methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, vinylmethyltrimethoxysilane, vinylethyltrimethoxysilane, p-styryltrimethoxysilane, p-styryltriethoxysilane 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, vinylmethyltrimethoxysilane, vinylethyltrimethoxysilane, p-styryltrimethoxysilane, p-styryltritooxy Silane is preferable.

As the catalyst, a compound that accelerates the dealcoholization condensation reaction between the silanol group of the silanol compound and the alkoxysilyl group of the alkoxysilane compound can be used.
Suitable catalysts include the following general formula (2):
M ₁ (OR ₃ ) _n (2)
{Wherein, M ₁ is any one of silicon, germanium, titanium, zirconium, boron, or aluminum, and each of the plurality of R ₃ is independently an alkyl group having 1 to 4 carbon atoms, and n is 3 or 4. }, Or at least one catalyst selected from the group consisting of alkali metal hydroxides and alkaline earth metal hydroxides (hereinafter also referred to simply as “metal alkoxides”). The compound of this is mentioned.

  The metal alkoxide represented by the above general formula (2) catalyzes the dealcoholization condensation reaction between the silanol compound (silanol group) and the alkoxysilane compound (alkoxysilyl group), and also acts as an alkoxy group-containing compound to dealcoholize. A polysiloxane or polysilsesquioxane structure is formed in a form that participates in the reaction and is incorporated into the molecule.

  A polyorganosiloxane can be polymerized by suitably mixing and heating a suitably used silanol compound, alkoxysilane compound, and catalyst. The heating temperature at this time is an important parameter for controlling the degree of polymerization of the polyorganosiloxane produced. Although depending on the desired degree of polymerization, it is preferred that the raw material mixture is heated at 70 ° C. to 150 ° C. for polymerization.

As for what passed through the step which hydrolyzes the said silanol compound and the said alkoxysilane compound for 30 to 1 hour at the temperature of 75-85 degreeC, without adding water positively, Fraunhofer ISC Germany "ORMOCER" ( (Registered trademark) ONE.
As a photocurable resin composition, you may contain a photoinitiator, various additives, etc. in the said polyorganosiloxane.

  EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to this Example.

<Photocurable resin composition>
After mixing DPD and MEMO in a 1: 1 molar ratio, it was hydrolyzed at a temperature of 75 to 85 ° C. for 30 to 1 hour without actively adding water to make a photocurable resin from Fraunhofer ISC of Germany. The obtained ORMCER (registered trademark) ONE (ORMOCER ONE synthesis reaction temperature was 80 ° C., reaction time was 15 minutes, the catalyst was Ba (OH) ₂ H ₂ O 0.002 mol), radical photopolymerization initiator IRGACURE ( (Registered trademark) 814 (manufactured by Ciba Specialty Chemicals Co., Ltd.) 1.0% by mass was added and mixed, and the mixture was filtered through a 0.2 μm filter to obtain a photocurable resin composition. The final viscosity was 15 poise.

<Member with mold pattern>
1.0 g of CATALYST184 was added to 10.0 g of SILPOT184 W / C (manufactured by Dow Corning Toray) and stirred to obtain a member solution having a transparent pattern.
After adding 1 g of acrylic fine particles SX-350H (2.5 μm diameter beads manufactured by Soken Chemical Co., Ltd.) to 10.0 g of SILPO T184 W / C (manufactured by Dow Corning Toray), 1.0 g of CATALYST 184 is added and stirred to diffuse. A member solution having a mold pattern was obtained.
The liquid for members having a transparent pattern was applied to a box-shaped quartz master mold (5 cm × 5 cm) with a wall having a height of 5 mm to a thickness of 1 mm. After carrying out vacuum defoaming for 30 minutes, it was placed on an 80 degree hot plate, cured, and allowed to stand at room temperature.
Without peeling off the first layer of PDMS from the master mold, apply the component liquid having the above diffusion pattern on the second layer with a thickness changed to 2, 3, 4 mm so that the total PDMS thickness is 2, 3 and 4 mm. After defoaming, it was placed on an 80 degree hot plate and cured. Three types of light diffusive mold patterns with different light diffusivities (each thickness 2, 3, 4 mm, haze value 49, 75, 85) by leaving the substrate at room temperature and then peeling it off and changing the thickness. Members 1, 2, 3 having
Further, without applying the member liquid having a diffusion pattern, the first layer of PDMS was peeled from the master mold to obtain a member having a transparent pattern having a thickness of about 1 mm.

[Example 1]
Using the nanoimprint apparatus manufactured by Myeongchang Kiko Co., Ltd., using the 1 mm thick PC resin plate as a spacer, the above-mentioned photocurable resin composition is dropped on a glass substrate coated with a fluororesin (5 cm × 5 cm, thickness 0.7 mm), The member 1 (refractive index 1.41) having the above-described light diffusive mold pattern is placed on a support glass (non-alkali glass with UV light transmission, Corning 1737, refractive index 1.51) having a thickness of 0.7 mm. The light-transmitting mold 1 was formed by laminating the air so that there was no air between them. With the PDMS surface of the light-transmitting mold 1 facing down (the photocurable resin composition side), the finger is brought into close contact with the photocurable resin composition, and the illuminance on the photocurable resin composition surface is increased without pressing. The film was exposed at 8 mW / cm ² (365 nm wavelength) for 60 seconds. After 60 seconds from the exposure, the light transmissive mold 1 was peeled off, and the following evaluation was performed.
The results are shown in Table 1.

<Evaluation>
1) Surface curability: The surface cured property was determined by touching the obtained cured product with a finger.
No surface tackiness; ○
With surface tackiness; ×
2) Appearance of cured product: The obtained cured product was visually observed.
No transparent unevenness; ○
Slightly uneven; △
You can clearly see unevenness; ×
3) Transparency: UV transmittance: Hitachi spectrophotometer U-3040 was used. The transmittance of 550 nm of the cured product in a state of being attached to an alkali-free glass substrate was measured without any reference.

[Examples 2-3]
In Example 1, instead of the member 1 having the light diffusive mold pattern, the light transmissive mold 2 or 3 is prepared by using the member 2 or 3 having the light diffusive mold pattern. The same operation as in Example 1 was performed except that it was used.

[Example 4]
In Example 1, instead of the light transmissive mold 1, a member having the transparent pattern was formed with a support glass having a thickness of 0.7 mm (UV light transmissive non-alkali glass, Corning 1737, the surface opposite to the transparent mold). Sandblast treatment is performed, and a hemispherical uneven shape with a diameter of about 50 μm and a thickness of about 30 μm is laminated on the light-transmitting mold 4 so that no air exists between them. The same operation as in Example 1 was performed except that it was used.

[Comparative Example 1]
In Example 1, it replaced with the translucent mold 1, and performed similarly to Example 1 except having used this as a transparent mold using the member which has the above-mentioned transparent type | mold pattern.

[Comparative Example 2]
In Example 4, it replaced with the light transmissive mold 4, and performed similarly to Example 4 except having installed the member which has a transparent type | mold pattern, and support glass about 1 cm apart. Since the light from the supporting glass spread to the surroundings and an air layer was generated between them, the illuminance on the surface of the photocurable resin composition was attenuated by about 40% to 5 mW / cm ² (365 nm wavelength).

INDUSTRIAL APPLICABILITY The present invention can be used for producing plastic lenses, for example, optical lenses for imaging, lenses for LEDs, and optical waveguides, using the photocurable resin composition.

Claims (10)

Production of a plastic lens or an optical waveguide obtained by arranging a light source, a light transmissive mold and a light curable resin composition in this order and irradiating light through the light transmissive mold to lightly cure the light curable resin composition A method for producing a plastic lens or an optical waveguide, wherein the light transmissive mold has light diffusibility. The method for producing a plastic lens or an optical waveguide according to claim 1, wherein the haze value at 365 nm of the light transmissive mold is 50% or more and the light transmittance at 365 nm is 80% or more. The light transmissive mold has a mold pattern with a thickness of 0.2 mm to 5 mm on the surface on the photocurable resin composition side, and has an uneven shape with a thickness of 0.1 μm to 50 μm on the surface on the light source side. Or the manufacturing method of the plastic lens or optical waveguide of 2. The method for producing a plastic lens or an optical waveguide according to claim 3, wherein the irregular shape of 0.1 µm to 50 µm is spherical or hemispherical. The method for producing a plastic lens or an optical waveguide according to any one of claims 1 to 4, wherein the light transmissive mold is a mold in which fine particles having a refractive index different from that of a mold material are dispersed inside the mold. The method for producing a plastic lens or an optical waveguide according to any one of claims 1 to 5, wherein the light transmissive mold is a mold made of polydimethylsiloxane.   The light transmissive mold is a mold obtained by laminating a resin having a mold pattern on quartz or glass, and the quartz or glass has light diffusibility. The manufacturing method of the plastic lens or optical waveguide of description. The method for producing a plastic lens or an optical waveguide according to claim 7, wherein the resin having the mold pattern is polydimethylsiloxane. The light transmissive mold is a mold obtained by laminating a member having a mold pattern on a support having light diffusibility so that the mold pattern surface is on the outside, and the support and the mold pattern are The manufacturing method of the plastic lens or optical waveguide as described in any one of Claims 1-8 whose refractive index difference with the member to have is 0.1 or less. The light transmissive mold is a mold in which quartz or glass is used as a support having light diffusibility, polydimethylsiloxane is used as a member having a mold pattern, and laminated so that no air exists between the two. 10. A method for producing a plastic lens or an optical waveguide according to 9.