JP2009161487A - Cage-type polysilsesquioxane derivative, resin precursor composition for optical material containing the same, resin for optical material, and optical element, and method for producing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical material with low refractive index and high dispersion realized simultaneously at high levels, enabling improving the diffraction efficiency of high-adhesion multiple-layered diffraction optical elements. <P>SOLUTION: A resin precursor composition for optical material is provided, containing a cage-type polysilsesquioxane derivative of formula (1) [wherein, at least one of R<SP>11</SP>to R<SP>13</SP>, R<SP>21</SP>to R<SP>23</SP>, R<SP>31</SP>to R<SP>33</SP>, R<SP>41</SP>to R<SP>43</SP>, R<SP>51</SP>to R<SP>53</SP>, R<SP>61</SP>to R<SP>63</SP>, R<SP>71</SP>to R<SP>73</SP>, and R<SP>81</SP>to R<SP>83</SP>is a group of formula (2) (wherein, X is a 1-3C alkyl, and m and n are each independently an integer of 0-5); at least one of the remaining groups is a (meth)acryloxyalkyl; and the further remaining groups are each independently H, OH or a 1-3C alkyl]. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cage-type polysilsesquioxane derivative, a resin precursor composition for an optical material including the same, a resin for an optical material, an optical element, and a method for producing them.

  Adhesive multilayer diffractive optical elements, in which two optical members made of an optical material are in close contact with each other to form a diffraction grating, can broaden the wavelength used, and the alignment between the grating and the grating is also possible. It has the advantage of being easy.

  In this close-contact multilayer diffractive optical element, for example, as described in JP-A-9-127322 (Patent Document 1), the optical characteristics of the two optical members sandwiching the diffractive optical surface are relatively high refractive. It is required to have low refractive index dispersion and low refractive index high dispersion.

  As such an optical material, a resin is suitable in that it can be reduced in weight. Further, by using a resin, moldability and mass productivity can be improved, and manufacturing at a low cost can be realized. In particular, the ultraviolet curable resin is excellent in transferability, has a short time required for curing, and does not require a heat source, and thus can be manufactured at a lower cost.

However, it has been difficult to achieve low refractive index and high dispersion at the same time at a high level with resins that have been used in the optical field in the past, and the adhesive multilayer is combined with a relatively high refractive index and low dispersion resin. Even when the diffractive optical element is configured, there are limits to improving the diffraction efficiency and widening the wavelength used. For this reason, a novel low refractive index and high dispersion resin has been demanded. For example, International Publication No. 2006/068137 (Patent Document 2) discloses a bifunctional fluorine-containing (meth) acrylate, a bifunctional (meth) acrylate having a fluorene structure, and photopolymerization as a low refractive index and high dispersion resin. A cured product of a resin precursor composition containing an initiator is disclosed.
JP-A-9-127322 International Publication No. 2006/068137 Pamphlet

  The present invention has been made in view of the above-described problems of the prior art, and enables low refractive index and high dispersion simultaneously at a high level, which can improve the diffraction efficiency of the contact multilayer diffractive optical element. An object is to provide a realized optical material.

  As a result of intensive studies to achieve the above object, the present inventors have been able to reduce the refractive index of an optical material, and the polysilsesquioxane derivative having a cage structure has an aromatic ring. It has been found that polysilsesquioxane derivatives can impart high dispersion performance to optical materials. Furthermore, it discovered that the polysilsesquioxane derivative which has a (meth) acryl group was excellent in compatibility with a resin precursor. As a result, the polysilsesquioxane derivative having these structures can simultaneously achieve low refractive index and high dispersion of optical materials at a high level, and a uniform resin precursor composition for optical materials As a result, the present invention was completed.

  That is, the cage-type polysilsesquioxane derivative of the present invention has the following formula (1):

Represented by
In the formula ^{(1), R 11 ~R 13} , R 21 ~R 23, R 31 ~R 33, R 41 ~R 43, R 51 ~R 53, R 61 ~R 63, R 71 ~R 73, and At least one of R ^{81 to} R ⁸³ is represented by the following formula (2):

(In formula (2), X is an alkyl group having 1 to 3 carbon atoms, and m and n are each independently an integer of 0 to 5).
A group represented by
At least one of the remaining groups is a (meth) acryloxyalkyl group;
Further, the remaining groups are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 3 carbon atoms.
It is characterized by this.

R ^{11 to} R ¹³ , R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ^{41 to} R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ in the formula (1), and 2 to 5 of R ^{81 to} R ⁸³ are preferably groups represented by the formula (2), and 1 to 4 of the remaining groups are (meth) acryloxyalkyl groups. preferable.

  The resin precursor composition for an optical material of the present invention includes a cage-type polysilsesquioxane derivative (A) of the present invention, a bifunctional (meth) acrylate (B) having a fluorene structure, and the bifunctional (meth). It contains bifunctional fluorine-containing (meth) acrylate (C) other than acrylate (B). Moreover, it is preferable that the resin precursor composition for optical materials of this invention contains a photoinitiator (D) further.

The resin for optical materials of the present invention is obtained by curing the resin precursor composition for optical materials of the present invention. This resin for optical materials has a refractive index with respect to d-line (587.562 nm), C-line (656.273 nm), and F-line (486.133 nm) at 22.5 ° C. of the following formulas (I) and (II):
n _d ≦ (n _F −n _C ) × 6.24 + 1.42 (I)
1.48 ≦ n _d ≦ 1.56 (II)
(In formulas (I) and (II), n _d , n _C , and n _F represent the refractive indices for d line, C line, and F line, respectively.)
It is preferable that the condition represented by

An optical element according to the present invention includes a first optical member made of a first optical material, and a second optical member made of a second optical material and disposed on the first optical member. Because
A diffraction grating is formed at the interface between the first optical member and the second optical member,
The refractive index of the first optical material for d-line, C-line and F-line at 22.5 ° C. and the refractive index of the second optical material for d-line, C-line and F-line at 22.5 ° C. Formulas (III) and (IV) below:
n _1d <n _2d (III)
_{n 1F -n 1C> n 2F -n} 2C (IV)
(In the formula (III), n _1d and n _2d represent the refractive indexes of the first and second optical materials with respect to the d-line, respectively, and in the formula (IV), n _1C and n _1F represent the first optical material of the first optical material, respectively. Refractive indexes for C line and F line are shown, and n _2C and n _2F are refractive indexes for C line and F line of the second optical material, respectively.
Meets the conditions
The first optical material is a resin for optical materials obtained by curing a resin precursor composition containing the cage polysilsesquioxane derivative of the present invention.
It is characterized by this. The first optical material is preferably the optical material resin of the present invention.

  The method for producing a cage-type polysilsesquioxane derivative of the present invention has the following formula (3):

(And in the formula ^{(3), R 111 ~R 113} , R 121 ~R 123, R 131 ~R 133, R 141 ~R 143, R 151 ~R 153, R 161 ~R 163, R 171 ~R 173, Two or more of R ^{181 to} R ¹⁸³ are hydrogen atoms, and the remaining groups are alkyl groups having 1 to 3 carbon atoms.)
A cage-type polysilsesquioxane represented by
Following formula (4)

(In Formula (4), X is a C1-C3 alkyl group, and m and n are the integers of 0-5 each independently.)
A diphenylacetylene compound represented by:
An (meth) acrylic acid alkenyl compound;
It is characterized by reacting.

The method of manufacturing an optical element of the present invention includes a step of forming a diffraction grating shape on a first optical member made of a first optical material,
Forming a second optical member made of a second optical material on the diffraction grating shape;
A method for producing an optical element comprising:
The first optical material is a resin for optical materials obtained by curing a resin precursor composition containing the cage polysilsesquioxane derivative according to claim 1 or 2,
The second optical material is a refractive index of the first optical material with respect to d-line, C-line and F-line at 22.5 ° C., and d-line and C-line of the second optical material at 22.5 ° C. , The refractive index with respect to the F-line is the following formulas (III) and (IV)
n _1d <n _2d (III)
_{n 1F -n 1C> n 2F -n} 2C (IV)
(In the formula (III), n _1d and n _2d represent the refractive indexes of the first and second optical materials with respect to the d-line, respectively, and in the formula (IV), n _1C and n _1F represent the first optical material of the first optical material, respectively. Refractive indexes for C line and F line are shown, and n _2C and n _2F are refractive indexes for C line and F line of the second optical material, respectively.
Satisfying the condition represented by
It is characterized by this.

  According to the present invention, low refractive index and high dispersion of an optical material can be simultaneously realized at a high level, and further, the diffraction efficiency of a contact multilayer diffractive optical element can be improved.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

<Cage type polysilsesquioxane derivative>
First, the cage type polysilsesquioxane derivative of the present invention will be described. The cage-type polysilsesquioxane derivative of the present invention has the following formula (1):

It has the structure represented by these.

In the formula ^{(1), R 11 ~R 13} , R 21 ~R 23, R 31 ~R 33, R 41 ~R 43, R 51 ~R 53, R 61 ~R 63, R 71 ~R 73, and At least one of R ^{81 to} R ⁸³ is represented by the following formula (2):

(In formula (2), X is an alkyl group having 1 to 3 carbon atoms, and m and n are each independently an integer of 0 to 5).
It is group represented by these. At least one of the remaining groups is a (meth) acryloxyalkyl group, and the remaining groups are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 3 carbon atoms.

  The cage-type polysilsesquioxane derivative of the present invention having a cage structure as shown in the above formula (1) has relatively large voids between molecules and within the molecule. The refractive index can be lowered.

The cage polysilsesquioxane derivative has a diphenylvinyl structure as shown in the formula (2). Thereby, high dispersion performance can be imparted to the optical material. Since this diphenylvinyl structure has two aromatic rings in one structure, it can efficiently impart high dispersion performance. In the formula (1), R ^{11 to} R ¹³ , R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ^{41 to} R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ , and preferably one of R ⁸¹ to R ⁸³ is two to five (more preferably one 3-5) is a group represented by the formula (2). When the number of groups represented by the formula (2) is less than the lower limit, sufficient high dispersion performance tends not to be imparted to the optical material. On the other hand, when the above upper limit is exceeded, synthesis tends to be difficult due to steric hindrance.

The cage-type polysilsesquioxane derivative has a (meth) acryloxyalkyl group. As a result, copolymerization with a resin precursor, which will be described later, and ultraviolet rays becomes possible. In the formula (1), R ^{11 to} R ¹³ , R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ^{41 to} R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ , and Preferably 1-4 (more preferably 1-3) of R < ⁸¹ > -R < ⁸³ > are (meth) acryloxyalkyl groups. When the number of (meth) acryloxyalkyl groups is less than the above lower limit, the copolymerizability with the resin precursor described later tends to decrease. On the other hand, when the above upper limit is exceeded, synthesis tends to be difficult due to steric hindrance. Moreover, it is preferable that carbon number of the alkyl group in the said (meth) acryloxyalkyl group is 2-6 from a viewpoint of enlarging dispersion | distribution of a cage-type polysilsesquioxane derivative.

Moreover, from the above viewpoints, the cage-type polysilsesquioxane derivative of the present invention has the following formula (1): R ^{11 to} R ¹³ , R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ⁴¹ to 2 to 5 of R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ , and R ^{81 to} R ⁸³ are groups represented by the formula (2), and the remaining groups It is more preferable that 1-4 of them are (meth) acryloxyalkyl groups, 3-5 are groups represented by the formula (2), and 1-3 of the remaining groups are (meta Particularly preferred is an acryloxyalkyl group.

Further, in consideration of steric hindrance during synthesis, when one of R ^{11 to} R ¹³ is a group represented by the above formula (2) or a (meth) acryloxyalkyl group, the remaining two groups Most preferably, each independently represents a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 3 carbon atoms. The same applies to R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ^{41 to} R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ , and R ^{81 to} R ^83. .

  Since the cage-type polysilsesquioxane derivative of the present invention has a diphenylvinyl structure and a (meth) acryloxyalkyl group, compatibility with the resin precursor is improved, and white turbidity due to phase separation during curing is also prevented. can do.

  Such a cage-type polysilsesquioxane derivative can be produced, for example, by the following method. Following formula (3):

(And in the formula ^{(3), R 111 ~R 113} , R 121 ~R 123, R 131 ~R 133, R 141 ~R 143, R 151 ~R 153, R 161 ~R 163, R 171 ~R 173, Two or more, preferably four or more of R ^{181 to} R ¹⁸³ are hydrogen atoms, and the remaining groups are alkyl groups having 1 to 3 carbon atoms.)
In the basket-type polysilsesquioxane represented by the following formula (4):

(In Formula (4), X, m, and n are synonymous with X, m, and n in Formula (2).)
The diphenylacetylene compound represented by the above and an alkenyl (meth) acrylate compound are subjected to an addition reaction in a solvent.

Considering the steric hindrance during this addition reaction, in the formula (3), a group consisting of R ^{111 to} R ¹¹³ , a group consisting of R ^{121 to} R ¹²³ , a group consisting of R ^{131 to} R ¹³³ , and R ^{141 to} R the group consisting of ^143, the group consisting of R 151 ^{to R 153,} the group consisting of R 161 ^{to R 163,} the group consisting of R 171 ^{to R 173,} and for each of the group consisting of ^R 181 ^{to R 183,} the three substituents More preferably, at least one of them is a hydrogen atom.

  Such a cage-type polysilsesquioxane can be prepared, for example, by the following method. First, a tetraalkoxysilane is subjected to a condensation reaction in the presence of an amino alcohol to prepare an ammonium salt of a cage-type polysilsesquioxane. Subsequently, the cage-type polysilsesquioxane represented by the above formula (3) is obtained by reacting the ammonium salt of the cage-type polysilsesquioxane with a monohalogenated alkylsilane.

  Moreover, it is preferable that carbon number of the alkenyl group in the said (meth) acrylic acid alkenyl compound is 2-6 from a viewpoint of enlarging dispersion | distribution of a cage-type polysilsesquioxane derivative. Examples of the solvent used for the addition reaction include dehydrated solvents such as dehydrated toluene. In order to avoid gelation during the addition reaction, it is desirable to remove moisture from the reaction system, and it is desirable to dry the apparatus, vacuum heat dry the reaction product, use a dehydrating solvent, and react in an argon or nitrogen atmosphere. If necessary, it is desirable to distill or dry the monomer to be used.

  It is preferable to select an appropriate temperature for the addition reaction according to the catalyst used. Since the (meth) acryloxyalkyl group undergoes a polymerization reaction by both light and heat, it is important that the polymerization reaction is not caused when the substituent is introduced. Therefore, in addition to shielding the reaction system, the reaction is carried out under cooling using a catalyst in which the reaction proceeds even at a low temperature, such as a siloxane complex xylene solution at 2.1 to 2.4% by mass of platinum (0) divinyl. It is desirable. However, cooling to below the freezing point is not preferable because the reaction rate becomes too slow and the reaction proceeds while rapidly generating heat in the process of returning from below freezing to room temperature. In addition, starting the reaction at around room temperature is not preferable because a local temperature increase when the reactant is dropped cannot be avoided. Therefore, the preferable reaction temperature for avoiding the polymerization of the (meth) acryloxyalkyl group is 5 to 10 ° C., and after the dropping of the reaction product is completed, it is preferable to raise the temperature gently to room temperature.

<Resin precursor composition for optical material and resin for optical material>
Next, the resin precursor composition for optical materials and the resin for optical materials of the present invention will be described. The resin precursor composition for optical materials of the present invention comprises a cage-type polysilsesquioxane derivative (A), a bifunctional (meth) acrylate (B) having a fluorene structure, and the bifunctional (meth) acrylate (B ) Containing a bifunctional fluorine-containing (meth) acrylate (C) and a photopolymerization initiator (D) as necessary.

(A) Cage type polysilsesquioxane derivative:
The cage-type polysilsesquioxane derivative (A) used in the present invention is a cage-type polysilsesquioxane derivative represented by the above formula (1). This cage-type polysilsesquioxane derivative (A) may be used individually by 1 type, and may use 2 or more types together.

  The content of the cage polysilsesquioxane derivative (A) in the resin precursor composition for an optical material of the present invention is preferably 10 to 90% by mass, and more preferably 20 to 70% by mass. . When the content of the cage-type polysilsesquioxane derivative (A) is less than the above lower limit, the dispersion in the optical material tends to be small. On the other hand, when the upper limit is exceeded, the viscosity tends to be high and handling tends to be difficult.

  In addition, when the resin for optical materials of the present invention is used as a low refractive index and high dispersion resin for a contact multilayer diffractive optical element, the content of the cage polysilsesquioxane derivative (A) exceeds the above upper limit. If it exceeds, the refractive index increases and the refractive index difference from the high refractive index and low dispersion resin tends to be small. As a result, the grating height of the diffraction grating must be increased, and the optical performance and productivity tend to deteriorate.

(B) Bifunctional (meth) acrylate:
Examples of the bifunctional (meth) acrylate (B) (hereinafter referred to as “bifunctional (meth) acrylate (B)”) having a fluorene structure used in the present invention include the following formula (5):

The compound represented by these is mentioned. In formula (5), R ³ and R ⁴ are each independently — ((CH ₂ ) _p O) _m or — (CH ₂ CH (OH) CH ₂ O) _m (where m is 1 to 3). And p is an integer of 2 to 4), R ^{5 to} R ¹⁰ are each independently a hydrogen atom, a fluorine atom, a hydrocarbon group having 1 to 6 carbon atoms, a phenyl group, a fluorinated phenyl group, or a phenyl group which is a hydrocarbon group having 1 to 6 carbon atoms is substituted, R ¹¹ to R ¹² represents a hydrogen atom or a methyl group independently. These bifunctional (meth) acrylate (B) may be used individually by 1 type, and may use 2 or more types together.

  Since this bifunctional (meth) acrylate (B) has a fluorene structure, it is effective for imparting high dispersion performance. Moreover, since it has a (meth) acryl group, it is excellent also in compatibility. Furthermore, when it contains a fluorine atom, the refractive index of the optical material can be lowered.

  The content of the bifunctional (meth) acrylate (B) in the resin precursor composition for an optical material of the present invention is preferably 2 to 40% by mass, and more preferably 10 to 40% by mass. When the content of the bifunctional (meth) acrylate (B) is less than the lower limit, it tends to be difficult to impart sufficient high dispersion performance to the optical material. On the other hand, when the above upper limit is exceeded, the viscosity of the resin precursor composition becomes too high, and workability tends to be lowered, and it is difficult to sufficiently reduce the refractive index.

(C) Bifunctional fluorine-containing (meth) acrylate:
Examples of the bifunctional fluorine-containing (meth) acrylate (C) (hereinafter referred to as “bifunctional (meth) acrylate (C)”) other than the bifunctional (meth) acrylate (B) used in the present invention are as follows. The following formula (6):

The compound represented by these is mentioned. In Formula (6), R ¹ and R ² each independently represent a hydrogen atom or a methyl group, x is an integer of 1 to 2, and Y is a C 2-12 perfluoroalkyl group or — (CF _{2 -O-CF 2)} shows the _2, z is an integer of 1 to 4.

  Specifically, 1,4-di (meth) acryloyloxy-2,2,3,3-tetrafluorobutane, 1,6-di (meth) acryloyloxy-3,3,4,4-tetrafluorohexane 1,6-di (meth) acryloyloxy-2,2,3,3,4,4,5,5-octafluorohexane, 1,8-di (meth) acryloyloxy-3,3,4,4 , 5,5,6,6-octafluorooctane, 1,8-di (meth) acryloyloxy-2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoro Octane, 1,9-di (meth) acryloyloxy-2,2,3,3,4,4,5,5,6,6,7,7,8,8-tetradecafluorononane, 1,10- Di (meth) acryloyloxy-2,2,3,3,4,4,5,5,6,6,7 7,8,8,9,9-hexadecafluorodecane, 1,12-di (meth) acryloyloxy-2,2,3,3,4,4,5,5,6,6,7,7, Examples include 8, 8, 9, 9, 10, 10, 11, 11-icosafluorododecane. Moreover, ethylene oxide modified bisphenol F di (meth) acrylate, propylene oxide modified bisphenol F di (meth) acrylate, and the like can also be used as the bifunctional (meth) acrylate (C). These bifunctional (meth) acrylate (C) may be used individually by 1 type, and may use 2 or more types together.

  Since this bifunctional (meth) acrylate (C) contains a fluorine atom, the refractive index of the optical material can be lowered. Moreover, since it has a (meth) acryl group, it is excellent also in compatibility. Furthermore, an increase in viscosity of the resin precursor composition due to the bifunctional (meth) acrylate (B) can be suppressed.

  The content of the bifunctional (meth) acrylate (C) in the resin precursor composition for an optical material of the present invention is preferably 5 to 75% by mass, and more preferably 20 to 75% by mass. When the content of the bifunctional (meth) acrylate (C) is less than the lower limit, the viscosity increase of the resin precursor composition due to the bifunctional (meth) acrylate (B) cannot be sufficiently suppressed, and workability is improved. It tends to decrease. On the other hand, when the above upper limit is exceeded, the dispersion of the resin precursor composition for optical materials tends to be small.

(Other (meth) acrylates)
In addition to the bifunctional (meth) acrylates (B) and (C), the resin precursor composition for optical materials of the present invention may contain other (meth) acrylates copolymerizable therewith as necessary. You may make it contain. Thereby, the viscosity of the resin precursor composition can be adjusted, and the transparency of the cured product (resin for optical material) can be improved.

  Examples of the other (meth) acrylates include 1 to 4 functional (meth) acrylates. These 1-4 functional (meth) acrylates preferably do not contain sulfur, chlorine, bromine or alicyclic structures. When these atoms or structures are included, the dispersibility of the optical material tends to decrease. As a 1-4 functional (meth) acrylate, the (meth) acrylate illustrated as a 3rd component in the international publication 2006/068137 pamphlet is raised, for example. These other (meth) acrylates may be used alone or in combination of two or more.

  It is preferable that the content rate of the said other (meth) acrylate in the resin precursor composition for optical materials of this invention is 40 mass% or less. If the content of other (meth) acrylates exceeds the above upper limit, it tends to be difficult to simultaneously realize low refractive index and high dispersion at a high level.

(D) Photopolymerization initiator:
The said photoinitiator (D) is not specifically limited, What is normally used for photocurable resin can be selected suitably, and can be used.

(Other additives)
The resin precursor composition for an optical material of the present invention can contain various additives such as a stabilizer and an ultraviolet absorber as necessary.

  The resin for optical materials of the present invention is obtained by curing the resin precursor composition for optical materials by heating or ultraviolet irradiation. Since this optical material resin includes a structure derived from the cage-type polysilsesquioxane derivative represented by the above formula (1), low refractive index and high dispersion can be simultaneously achieved at a high level.

The resin for optical materials of the present invention has a refractive index with respect to d-line (587.562 nm), C-line (656.273 nm), and F-line (486.133 nm) at 22.5 ° C. of the following formulas (I) and ( II):
n _d ≦ (n _F −n _C ) × 6.24 + 1.42 (I)
1.48 ≦ n _d ≦ 1.56 (II)
(In formulas (I) and (II), n _d , n _C , and n _F represent the refractive indices for d line, C line, and F line, respectively.)
It is preferable that the condition represented by A resin for optical materials satisfying the above conditions can be suitably used as a low refractive index and high dispersion material for a contact multilayer diffractive optical element.

<Optical element>
Next, the optical element of the present invention will be described. An optical element of the present invention includes a first optical member made of a first optical material and a second optical member made of a second optical material disposed on the first optical member. A contact multilayer diffractive optical element in which a diffraction grating is formed at the interface between the first optical member and the second optical member.

In the optical element of the present invention, the refractive index of the first optical material with respect to d-line, C-line, and F-line at 22.5 ° C. and the d-line, C-line at 22.5 ° C. of the second optical material, The refractive index for F-line is the following formulas (III) and (IV):
n _1d <n _2d (III)
_{n 1F -n 1C> n 2F -n} 2C (IV)
(In the formula (III), n _1d and n _2d represent the refractive indexes of the first and second optical materials with respect to the d-line, respectively, and in the formula (IV), n _1C and n _1F represent the first optical material of the first optical material, respectively. Refractive indexes for C line and F line are shown, and n _2C and n _2F are refractive indexes for C line and F line of the second optical material, respectively.
The condition represented by is satisfied.

  The first optical material is a resin for optical materials (low refractive index high dispersion resin) obtained by curing a resin precursor composition containing the cage polysilsesquioxane derivative of the present invention. As the resin precursor composition, the resin precursor composition for an optical material of the present invention is preferable from the viewpoint of the stability of the composition. The resin for an optical material of the present invention is homogeneous as the first optical material. Is preferred.

  On the other hand, the second optical material is not particularly limited as long as it satisfies the conditions represented by the formulas (III) and (IV). For example, a glass having a diffraction grating shape formed on the surface by molding a low melting glass, a conventionally known high refractive index low dispersion resin described in International Publication No. 2005/023363 pamphlet, other thermoplastic resins for injection molding, Various thermosetting resins are exemplified.

  The optical element of the present invention has a higher refractive efficiency because the low refractive index and high dispersion resin (first optical material) simultaneously achieves a low refractive index and high dispersion at a high level compared to the conventional one. Indicates.

  Such an optical element can be manufactured, for example, by the following method. First, a mold having a diffraction grating shape on the surface is placed on a base material such as glass. Next, the resin precursor composition containing the cage polysilsesquioxane derivative of the present invention is filled between the mold and the base material and cured. Thereby, the first optical member made of the first optical material (low refractive index and high dispersion resin) is formed on the base material, and at the same time, opposite to the interface of the first optical member with the base material. A diffraction grating shape is formed on the side surface.

  Further, instead of the method using the above-mentioned base material, a first mold having a continuous surface and a second mold having a diffraction grating shape on the surface are arranged to face each other. A resin precursor composition containing a cage-type polysilsesquioxane derivative may be filled and cured. Thereby, the 1st optical member which consists of a 1st optical material by which one surface is a continuous surface and the diffraction grating shape was formed in the opposite surface can be formed.

  Next, the mold is removed, and instead, a mold having a continuous surface is disposed on the first optical member. Subsequently, a resin precursor composition for forming the second optical material is filled between the mold and the first optical member and cured. Thereby, the second optical member made of the second optical material (high refractive index and low dispersion resin) is formed on the first optical member, and at the same time, the first optical member and the second optical member are formed. A diffraction grating is formed at the interface with the optical member.

  When glass having a diffraction grating shape formed on the surface is used as the second optical material instead of the high refractive index and low dispersion resin, the optical element of the present invention can be produced by the following method. . First, a mold having a continuous surface is placed on the surface on which the diffraction grating shape of the glass is formed. Subsequently, the resin precursor composition containing the cage polysilsesquioxane derivative of the present invention is filled between the mold and the glass and cured. Thereby, the first optical member made of the first optical material (low refractive index and high dispersion resin) is formed on the glass, and at the same time, the glass (second optical member) and the first optical member are formed. A diffraction grating is formed at the interface of the optical member.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example. A method for synthesizing the cage polysilsesquioxane and a method for preparing the resin precursor are shown below.

(Synthesis Example 1)
In a 500 ml eggplant flask, 50.2 g (241 mmol) of tetraethoxysilane (manufactured by Nacalai Tesque) and 57.0 g (236 mmol) of choline (manufactured by Tokyo Chemical Industry Co., Ltd.) were charged and stirred overnight at room temperature. During stirring, when ammonium salt of polysilsesquioxane precipitated and stirring became difficult, 50 ml of methanol (manufactured by Nacalai Tesque) was added to dissolve the ammonium salt of polysilsesquioxane. Thereby, a methanol solution of a uniform polysilsesquioxane ammonium salt was obtained.

  On the other hand, in a three-necked flask having a capacity of 1000 ml equipped with a reflux condenser and a stir bar, about 100 ml (91.15 g (964 mmol)) of chlorodimethylsilane (Tokyo Chemical Industry Co., Ltd.) and 200 ml of hexane (manufactured by Nacalai Tesque Co., Ltd.) And charged.

  The methanol solution of the polysilsesquioxane ammonium salt was added dropwise to the hexane solution of chlorodimethylsilane over about 1 hour while stirring with ice cooling. After completion of dropping, the temperature of the solution was returned to room temperature, and the organic layer was separated. The obtained organic layer was concentrated to about 50 ml by a rotary evaporator. 200 ml of acetonitrile (manufactured by Nacalai Tesque Co., Ltd.) was added to this concentrated solution, and the resulting white precipitate was filtered and dried under vacuum to obtain 22.2 g of a white powder.

  This white powder is represented by the following formula (7):

It was confirmed by the following procedure that it was a hexahedral cage polysilsesquioxane represented by the following formula. First, this white powder was identified by ¹ H-NMR measurement (solvent: CDCl ₃ saturated solution) and ²⁹ Si-NMR measurement (solvent: CDCl ₃ saturated solution). FIG. 1 shows a ¹ H-NMR spectrum, and FIG. 2 shows a ²⁹ Si-NMR spectrum. ^{In the 1} H-NMR spectrum, only the Si—CH ₃ peak (0.25 ppm) and the Si—H peak (4.72 ppm) were detected, and the other peaks were not detected. Further, in the ²⁹ Si-NMR spectrum, only two peaks of the skeleton Si peak (−108.3 ppm) and the side chain dimethylsilyl group (Si (CH ₃ ) ₂ H) (−1.5 ppm) are obtained. was detected. Therefore, the obtained white powder was composed of one kind of skeleton Si and one kind of side chain Si, and it was confirmed that the skeleton part has a closed cage structure.

  Next, mass spectrometry was performed on this white powder. When a JMS-700 manufactured by JEOL Ltd. was used as a mass spectrometer and analysis was performed by an FD (electrolytic desorption) ionization method, a peak at m / z = 1016 was detected. Moreover, when the analysis by EI (electron ionization) method was also implemented using the same apparatus, the result of m / z = 1016 was suggested similarly.

  From the above analysis results, it was confirmed that the obtained white powder was a cage-type polysilsesquioxane having a hexahedral structure represented by the above formula (7).

In addition, according to the literature (Chem. Mater., Vol. 8, No. 8, 1996, p. 1592-1593, from the bottom of the second column footnote, lines 21 to 9), in the ¹ H-NMR spectrum, The peak derived from the silyl group (SiH) in the formula (7) appears at 4.72 ppm, and the peak derived from the dimethylsilyl group (Si (CH ₃ ) ₂ H) appears at 0.25 ppm. In the ²⁹ Si-NMR spectrum, the peak of Si in the dimethylsilyl group (Si (CH ₃ ) ₂ H) in the formula (7) appears at −1.1 ppm, and the cage structure in the formula (7) The peak of Si (OSi (CH ₃ ) ₂ H bonded Si) appears at −107.8 ppm. On the other hand, as shown in FIGS. 1 and 2, the white powder obtained in Synthesis Example 1 has peaks at 0.25 ppm and 4.72 ppm in the ¹ H-NMR spectrum, and −1. In the ²⁹ Si-NMR spectrum. Peaks appeared at 5 ppm and -108.3 ppm. Also from this, it was confirmed that the obtained cage-type polysilsesquioxane was represented by the formula (7).

  The yield of the cage-type polysilsesquioxane obtained in Synthesis Example 1 was 74%.

(Preparation Example 1)
30 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene as a bifunctional (meth) acrylate (B) having a fluorene structure and 2 as a bifunctional fluorine-containing (meth) acrylate (C) , 2, 3, 3, 4, 4, 5, 5-octafluorohexane-1,6-diacrylate was mixed and stirred until uniform to prepare a resin precursor.

<Cage type polysilsesquioxane derivative>
Example 1
A 200-ml three-necked flask was equipped with a reflux condenser, a balloon filled with dry argon, a three-way cock, and a stirrer. The three-necked flask was heated with a drier to dry the inside of the system, and was repeatedly sucked with a vacuum pump and supplied with dry argon, and then the system was filled with dry argon.

  The three-necked flask was charged with 3.05 g (3.0 mmol) of the cage-type polysilsesquioxane obtained in Synthesis Example 1 and 20 ml of dehydrated toluene (manufactured by Kanto Chemical Co., Ltd., dehydrated solvent for organic synthesis). While stirring at room temperature, 100 μl of acetone dimethyl acetal (manufactured by Tokyo Chemical Industry Co., Ltd.), 50 μl of 2.1 to 2.4 mass% platinum (0) divinyldisiloxane complex xylene solution (manufactured by Gelest), 10 mg of hydroquinone monomethyl ether (manufactured by Nacalai Tesque Co., Ltd.) and 10 mg of 2,6-di-tert-butyl-4-dimethylaminomethylphenol (manufactured by Tokyo Chemical Industry Co., Ltd.) were added, and the cage-type polysilsesquioxy was added. A toluene solution of Sun was prepared. When the system became uniform, the system was cooled to 5 ° C., and the entire system was shielded from light with an aluminum foil.

  Meanwhile, 2.14 g (12.0 mmol) of diphenylacetylene (manufactured by Tokyo Chemical Industry Co., Ltd.) and 0.76 g (6.0 mmol) of allyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed with dehydrated toluene (Kanto Chemical ( Toluene solution containing diphenylacetylene and allyl methacrylate was prepared by dissolving in 30 ml of dehydrated solvent for organic synthesis).

  This solution was slowly added dropwise to the cooled toluene solution of the cage polysilsesquioxane with stirring. At this time, attention was paid so that the temperature in the system would not exceed 10 ° C. After completion of the dropwise addition, the mixture was stirred overnight at room temperature while being protected from light. Next, a small amount of triphenylphosphine (manufactured by Nacalai Tesque Co., Ltd.) and a small amount of granular activated carbon (manufactured by Wako Pure Chemical Industries, Ltd.) were added and stirred for 10 minutes, and then allowed to stand overnight.

  Thereafter, the granular activated carbon is filtered off, and the solvent is distilled off by a rotary evaporator, followed by vacuum drying, and the following formula (8):

4.8 g (yield 86%) of a cage-type polysilsesquioxane derivative represented by the formula:

This cage-type polysilsesquioxane derivative was identified by ¹ H-NMR measurement (solvent: CDCl ₃ saturated solution) and ²⁹ Si-NMR measurement (solvent: CDCl ₃ saturated solution). FIG. 3 shows a ¹ H-NMR spectrum, and FIG. 4 shows a ²⁹ Si-NMR spectrum. Table 1 shows the results of calculating the molar ratio of the substituent R and the like from the results shown in FIGS.

  From this result, among the 8 Rs in the formula (8), about 3 to 4 are diphenylvinyl groups, about 1 to 2 are methacryloxypropyl groups, and about 3 to 4 are hydrogen. It was an atom or a hydroxyl group. Further, as apparent from the results shown in FIG. 4, the peak of Si at the top of the cage structure is at the same position as in FIG. 2, and thus it was confirmed that the cage structure was maintained after the above synthesis reaction.

(Example 2)
The amount of the cage-type polysilsesquioxane obtained in Synthesis Example 1 was 9.15 g (9.0 mmol), the amount of dehydrated toluene was 60 ml, the amount of acetone dimethyl acetal was 200 μl, and 2.1 to 2.4% by mass. Except that the amount of the platinum (0) divinyldisiloxane complex xylene solution was changed to 100 μl, the amount of hydroquinone monomethyl ether to 45 mg, and the amount of 2,6-di-tert-butyl-4-dimethylaminomethylphenol to 45 mg. A toluene solution of a cage-type polysilsesquioxane was prepared in the same manner as in Example 1.

  Further, diphenylacetylene was changed in the same manner as in Example 1 except that the amount of diphenylacetylene was changed to 7.92 g (36.0 mmol), the amount of allyl methacrylate was 4.56 g (36.0 mmol), and the amount of dehydrated toluene was changed to 90 ml. A toluene solution containing acetylene and allyl methacrylate was prepared.

  Thereafter, the cage-type polysilicon represented by the formula (8) was obtained in the same manner as in Example 1 except that the toluene solution of the cage-type polysilsesquioxane and the toluene solution containing the diphenylacetylene and allyl methacrylate were used. 16.2 g (yield 91%) of the rusesquioxane derivative was obtained.

This cage-type polysilsesquioxane derivative was identified in the same manner as in Example 1. FIG. 5 shows a ¹ H-NMR spectrum, and FIG. 6 shows a ²⁹ Si-NMR spectrum. Table 2 shows the results of calculating the molar ratio of the substituent R and the like from the results shown in FIGS.

  From this result, among the 8 Rs in the formula (8), about 4 to 5 are diphenylvinyl groups, about 2 are methacryloxypropyl groups, and about 2 are hydrogen atoms or hydroxyl groups. there were. Further, as is clear from the results shown in FIG. 6, the peak of Si at the top of the cage structure is at the same position as in FIG. 2, and thus it was confirmed that the cage structure was maintained even after the synthesis reaction.

<Resin precursor composition for optical material and resin for optical material>
(Example 3)
50 parts by mass of the cage-type polysilsesquioxane derivative obtained in Example 1 (hereinafter referred to as “cage-type polysilsesquioxane derivative (A1)”) and 50 parts by mass of the resin precursor obtained in Preparation Example 1 Were mixed and stirred until uniform. 2 parts by mass of Irgacure 184 (manufactured by Ciba Specialty Chemicals) was added as a photopolymerization initiator to the obtained resin precursor composition.

The resin precursor composition was irradiated with ultraviolet rays of 100,000 mJ / cm ² to prepare a cured product (resin for optical material) having a thickness of 5 mm. The obtained cured product did not become cloudy and was capable of measuring the refractive index. D line of the cured product (587.562 nm), C line (656.273 nm), the refractive index for the F line _{(486.133nm) (n d, n} F, n C) , and Carl Zeiss Jena made refractometer ( PR-2 type) was measured at 22.5 ° C. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

Example 4
A resin precursor composition was prepared in the same manner as in Example 3 except that the amount of the cage polysilsesquioxane derivative (A1) was changed to 10 parts by mass and the amount of the resin precursor was changed to 90 parts by mass. A cured product was produced. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

(Example 5)
Instead of the cage-type polysilsesquioxane derivative (A1), the cage-type polysilsesquioxane derivative obtained in Example 2 (hereinafter referred to as “the cage-type polysilsesquioxane derivative (A2)”) is 50. A resin precursor composition was prepared in the same manner as in Example 3 except that a part by mass was used, and a cured product was produced. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

(Example 6)
Resin precursor composition in the same manner as in Example 5, except that the amount of the cage-type polysilsesquioxane derivative (A2) was changed to 46.4 parts by mass and the amount of the resin precursor was changed to 53.6 parts by mass. Was prepared to produce a cured product. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

(Example 7)
A resin precursor composition was prepared in the same manner as in Example 5 except that the amount of the cage polysilsesquioxane derivative (A2) was changed to 30 parts by mass and the amount of the resin precursor was changed to 70 parts by mass. A cured product was produced. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

(Comparative Example 1)
A resin precursor composition was prepared in the same manner as in Example 3 except that 100 parts by mass of the resin precursor was used without using a cage-type polysilsesquioxane derivative, and a cured product was produced. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

(Comparative Example 2)
The amount of the cage-type polysilsesquioxane obtained in Synthesis Example 1 is 6.1 g (6.0 mmol), the amount of dehydrated toluene is 40 ml, the amount of acetone dimethyl acetal is 200 μl, and 2.1 to 2.4% by mass. Except that the amount of the platinum (0) divinyldisiloxane complex xylene solution was changed to 100 μl, the amount of hydroquinone monomethyl ether to 65 mg, and the amount of 2,6-di-tert-butyl-4-dimethylaminomethylphenol to 65 mg. A toluene solution of a cage-type polysilsesquioxane was prepared in the same manner as in Example 1.

  On the other hand, 6.55 g (52.0 mmol) of allyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) is dissolved in 60 ml of dehydrated toluene (manufactured by Kanto Chemical Co., Ltd., dehydrated solvent for organic synthesis) and toluene containing allyl methacrylate is dissolved. A solution was prepared.

  Thereafter, the cage-type polysilsesquioxane represented by the above formula (8) was used in the same manner as in Example 1 except that the toluene solution of the cage-type polysilsesquioxane and the toluene solution containing the allyl methacrylate were used. 10.0 g (yield 94%) of the derivative was obtained.

This cage-type polysilsesquioxane derivative was identified in the same manner as in Example 1. FIG. 7 shows a ¹ H-NMR spectrum, and FIG. 8 shows a ²⁹ Si-NMR spectrum. Table 3 shows the results of calculating the molar ratio of the substituent R and the like from the results shown in FIGS.

  From this result, among the 8 Rs in the formula (8), about 6 were methacryloxypropyl groups, and about 1 to 2 were hydrogen atoms or hydroxyl groups. Further, as apparent from the results shown in FIG. 8, since the Si peak at the apex of the cage structure is at the same position as in FIG. 2, it was confirmed that the cage structure was maintained after the synthesis reaction.

2 parts by mass of Irgacure 184 as a photopolymerization initiator was added to 100 parts by mass of this cage-type polysilsesquioxane derivative. This composition was irradiated with ultraviolet rays of 100,000 mJ / cm ² to prepare a cured product having a thickness of 5 mm. The obtained cured product did not become cloudy and was capable of measuring the refractive index. The refractive index of this cured product was measured in the same manner as in Example 3. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

The cage-type polysilsesquioxane derivative synthesized in Comparative Example 2 showed good compatibility with methyl methacrylate and the resin precursor. However, since the dispersion (n _F -n _C ) was small, it was mixed with these. Even if a cured product is formed, a cured product having a low refractive index and a high dispersion desirable as a contact multilayer diffractive optical element cannot be obtained.

(Comparative Example 3)
The amount of the cage-type polysilsesquioxane obtained in Synthesis Example 1 was 6.1 g (6.0 mmol), the amount of dehydrated toluene was 30 ml, the amount of acetone dimethyl acetal was 200 μl, and 2.1 to 2.4% by mass. Except that the amount of the platinum (0) divinyldisiloxane complex xylene solution was changed to 50 μl, the amount of hydroquinone monomethyl ether to 30 mg, and the amount of 2,6-di-tert-butyl-4-dimethylaminomethylphenol to 30 mg. A toluene solution of a cage-type polysilsesquioxane was prepared in the same manner as in Example 1.

  Meanwhile, 2.62 g (25.2 mmol) of vinylbenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) and 3.18 g (25.2 mmol) of allyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) were mixed with dehydrated toluene (Kanto Chemical ( A toluene solution containing allyl methacrylate was prepared by dissolving in 40 ml of an organic synthesis dehydration solvent.

  Thereafter, the cage type represented by the formula (8) in the same manner as in Example 1 except that the toluene solution of the cage polysilsesquioxane and the toluene solution containing the vinylbenzene and the allyl methacrylate were used. 8.9 g (yield 77%) of a polysilsesquioxane derivative was obtained.

This cage-type polysilsesquioxane derivative was identified in the same manner as in Example 1. FIG. 9 shows a ¹ H-NMR spectrum, and FIG. 10 shows a ²⁹ Si-NMR spectrum. In addition, Table 4 shows the results of calculating the molar ratio of the substituent R and the like from the results shown in FIGS.

  From this result, among the eight Rs in the formula (8), about 2-3 are phenylethyl groups, about 2-3 are methacryloxypropyl groups, and about 1-2 are hydrogen. It was an atom or a hydroxyl group. Further, as apparent from the results shown in FIG. 10, since the Si peak at the apex of the cage structure is almost the same position as in FIG. 2, it was confirmed that the cage structure was maintained after the above synthesis reaction.

2 parts by mass of Irgacure 184 as a photopolymerization initiator was added to 100 parts by mass of this cage-type polysilsesquioxane derivative. Although this composition was irradiated with ultraviolet rays of 100,000 mJ / cm ² , it was not sufficiently cured and a cured product capable of measuring the refractive index could not be obtained. Therefore, the cage-type polysilsesquioxane derivative and isobornyl acrylate are mixed in several mixing ratios, and 2 parts by mass of Irgacure 184 as a photopolymerization initiator is added to 100 parts by mass of this composition. A cured product capable of measuring the refractive index was produced by irradiating ultraviolet rays of 000 mJ / cm ² . The measured value of the obtained refractive index was extrapolated to calculate the refractive index when only the cage-type polysilsesquioxane derivative of Comparative Example 3 was cured. Table 5 shows the values of n _d , n _F , n _C and n _F -n _C.

As is apparent from the results, the cage-type polysilsesquioxane derivative of Comparative Example 3 has a small refractive index (n _d ) but also a small dispersion (n _F −n _C ). Even when a cured product is formed by mixing the rusesquioxane derivative and the resin precursor, a cured product having a low refractive index and a high dispersion desirable as an adhesive multilayer diffractive optical element cannot be obtained.

  As is apparent from the results shown in Table 5, when the cage-type polysilsesquioxane derivative of the present invention having a diphenylvinyl group and a methacryloxyalkyl group is used (Examples 1 to 7), the adhesion multilayer A cured product having a low refractive index and high dispersion desirable as a diffractive optical element was obtained. On the other hand, when the cage-type polysilsesquioxane derivative of the present invention was not added (Comparative Example 1), when the cage-type polysilsesquioxane derivative containing no diphenylvinyl group was used (Comparative Example 2), and When a cage-type polysilsesquioxane derivative having a phenylethyl group instead of a diphenylvinyl group is used (Comparative Example 3), the cured product has a low refractive index but a small dispersion.

<Adhesive multilayer diffractive optical element>
(Example 8)
Tricyclodecane dimethanol diacrylate and di (2-mercaptoethyl) sulfide are mixed at a molar ratio of 2.5: 1, and tri (cyclopentanedimethanol diacrylate) is mixed with di (2-mercaptoethyl) sulfide using triethylamine as a catalyst. Addition gave an oligomer. 2 parts by mass of Irgacure 184 as a photopolymerization initiator was added to 100 parts by mass of this oligomer to obtain a composition for a high refractive index and low dispersion optical material.

This composition was irradiated with ultraviolet rays of 10,000 mJ / cm ² to prepare a cured product (high refractive index and low dispersion resin) having a thickness of 5 mm. Further, the resin precursor composition prepared in Example 6 was also irradiated with ultraviolet rays of 100,000 mJ / cm ² to prepare a cured product (low refractive index high dispersion resin) having a thickness of 5 mm.

The refractive indexes of these cured products with respect to h-line, g-line, F-line, e-line, d-line, C-line, and r-line were 22.5 using a refractometer manufactured by Carl Zeiss Jena (PR-2 type). Measured at ° C. The results are shown in Table 6. Incidentally, _n F -n _C for the high refractive index and low dispersion resin was 0.011.

Next, in the case where a contact multilayer diffractive optical element having a grating height of 15 μm is produced using the high refractive index low dispersion resin and the low refractive index high dispersion resin, the wavelength of the contact multilayer diffractive optical element is The diffraction efficiency η of m-order light at λ (unit: nm) was calculated using the following formulas (V) and (VI). FIG. 11 shows the calculation result for the primary light.
η = [sin {π (α−m)} / {π (α−m)}] ² (V)
α = {(n _1λ −1) − (n _2λ −1)} × d / λ (VI)
In formulas (V) and (VI), d denotes the height of the diffraction grating _{(nm), n} 1λ and _{n 2 [lambda]} is the refractive index of the optical member 1 and 2 at the wavelength λ, respectively.

  Next, an adhesive multilayer diffractive optical element is formed using the composition for high refractive index and low dispersion optical material and the resin precursor composition prepared in Example 6 as the composition for low refractive index and high dispersion optical material. A manufacturing method will be described.

  As shown in FIG. 12A, first, a silane coupling process is performed on the surface 2 of the glass base material 1 on which the resin layer is formed. Next, as shown in FIG. 12 (b), the mold 3 on which the lattice shape is formed and the treatment surface 2 are opposed to each other, and the resin precursor composition 4 prepared in Example 6 is filled therebetween. Then, the optical member 5 made of a low refractive index and high dispersion resin is formed by irradiating and curing ultraviolet rays. As the mold 3, for example, there is a diffraction grating having an outer diameter of 50 mm and a grating height of 15 μm, a grating pitch of 3.5 mm near the center, and 0.17 mm near the outer periphery, and the grating pitch becomes smaller as the outer periphery is closer. What is formed can be used. Thereafter, the mold is released as shown in FIG.

  Next, as shown in FIG. 12 (d), the optical member 5 and the mold 7 having no diffraction grating shape and having a continuous surface are opposed to each other, and the high refractive index and low dispersion optical material composition 6 therebetween. And is cured by irradiating with ultraviolet rays to form an optical member 8 made of a high refractive index and low dispersion resin. Thereafter, as shown in FIG. 12 (e), mold release is performed to obtain a contact multilayer diffractive optical element. This diffractive optical element exhibits high diffraction efficiency as calculated by the above formula.

(Comparative Example 4)
As bifunctional fluorine-containing (meth) acrylate, 59 parts by mass of 2,2,3,3,4,4,5,5-octafluorohexane-1,6-diacrylate and bifunctional (meth) acrylate having a fluorene structure As a mixture, 37 parts by mass of 9,9-bis [4- (2-acryloyloxyethoxy) phenyl] fluorene and 4 parts by weight of methoxypolypropylene glycol acrylate as a monofunctional acrylate were mixed and stirred until uniform, and the low refractive index A composition for a highly dispersed optical material was prepared.

2 parts by mass of Irgacure 184 as a photopolymerization initiator was added to 100 parts by mass of this composition. This composition was irradiated with ultraviolet rays of 10,000 mJ / cm ² to prepare a cured product (low refractive index high dispersion resin) having a thickness of 5 mm. The refractive index of this cured product was measured in the same manner as in Example 8. The results are shown in Table 7.

  Next, in the case where an adhesive multi-layer diffractive optical element having a grating height of 15 μm was produced using this low refractive index high dispersion resin and the high refractive index low dispersion resin described in Example 8, the same as in Example 8. Then, the diffraction efficiency η of m-order light at the wavelength λ (unit: nm) of the multi-contact diffractive optical element was calculated. FIG. 11 shows the calculation result for the primary light.

  As is clear from the results shown in FIG. 11, the adhesive multilayer diffractive optical element (Example 8) using the cage polysilsesquioxane derivative of the present invention is the cage polysilsesquioxane of the present invention. It was excellent in diffraction efficiency as compared with the case where no derivative was used (Comparative Example 4).

  As described above, according to the present invention, it is possible to simultaneously realize a low refractive index and high dispersion of an optical material at a high level.

  Therefore, the close-contact multilayer diffractive optical element of the present invention is excellent in diffraction efficiency, and thus is useful as an optical element used for optical products having a wide operating wavelength band such as a camera, a microscope, and binoculars.

2 is a graph showing a ¹ H-NMR spectrum of a cage-type polysilsesquioxane obtained in Synthesis Example 1. FIG. 2 is a graph showing a ²⁹ Si-NMR spectrum of a cage-type polysilsesquioxane obtained in Synthesis Example 1. FIG. 2 is a graph showing a ¹ H-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Example 1. FIG. 2 is a graph showing a ²⁹ Si-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Example 1. FIG. 2 is a graph showing a ¹ H-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Example 2. FIG. 2 is a graph showing a ²⁹ Si-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Example 2. FIG. 3 is a graph showing a ¹ H-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Comparative Example 2. FIG. 3 is a graph showing a ²⁹ Si-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Comparative Example 2. FIG. 6 is a graph showing a ¹ H-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Comparative Example 3. 4 is a graph showing a ²⁹ Si-NMR spectrum of a cage-type polysilsesquioxane derivative obtained in Comparative Example 3. It is a graph which shows the primary light diffraction efficiency in each wavelength of a contact | adherence multilayer type | mold diffractive optical element. It is sectional drawing which shows typically the optical raw material obtained by the manufacturing process of the contact | adherence multilayer type | mold diffractive optical element in Example 8, (a) is sectional drawing of the glass preform | base_material after a silane coupling process, b) is a cross-sectional view of the optical element after forming an optical member made of a low-refractive-index high-dispersion resin, (c) is a cross-sectional view of the optical element after release, and (d) is a high-refractive index low It is sectional drawing of the optical element after forming the optical member which consists of dispersion resin, (e) is sectional drawing of the optical element after mold release.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Glass base material, 2 ... Silane coupling process surface (resin layer formation surface), 3 ... Mold, 4 ... Low refractive index high dispersion resin precursor composition, 5 ... Optical which consists of low refractive index high dispersion resin Member: 6 ... Composition for high refractive index / low dispersion optical material, 7 ... Mold, 8 ... Optical member made of high refractive index / low dispersion resin.

Claims (10)

Following formula (1):

Represented by
In the formula ^{(1), R 11 ~R 13} , R 21 ~R 23, R 31 ~R 33, R 41 ~R 43, R 51 ~R 53, R 61 ~R 63, R 71 ~R 73, and At least one of R ^{81 to} R ⁸³ is represented by the following formula (2):

(In formula (2), X is an alkyl group having 1 to 3 carbon atoms, and m and n are each independently an integer of 0 to 5).
A group represented by
At least one of the remaining groups is a (meth) acryloxyalkyl group;
Further, the remaining groups are each independently a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 3 carbon atoms.
A cage-type polysilsesquioxane derivative characterized by that. R ^{11 to} R ¹³ , R ^{21 to} R ²³ , R ^{31 to} R ³³ , R ^{41 to} R ⁴³ , R ^{51 to} R ⁵³ , R ^{61 to} R ⁶³ , R ^{71 to} R ⁷³ in the formula (1), and 2 to 5 of R ^{81 to} R ⁸³ are groups represented by the formula (2),
1-4 of the remaining groups are (meth) acryloxyalkyl groups,
The cage-type polysilsesquioxane derivative according to claim 1, wherein:   Bifunctional other than the cage-type polysilsesquioxane derivative (A) according to claim 1 or 2, a bifunctional (meth) acrylate (B) having a fluorene structure, and the bifunctional (meth) acrylate (B). A resin precursor composition for optical materials, comprising fluorine-containing (meth) acrylate (C).   Furthermore, a photoinitiator (D) is contained, The resin precursor composition for optical materials of Claim 3 characterized by the above-mentioned.   A resin for an optical material obtained by curing the resin precursor composition for an optical material according to claim 3 or 4. The refractive indexes for the d-line, C-line and F-line at 22.5 ° C. are the following formulas (I) and (II)
n _d ≦ (n _F −n _C ) × 6.24 + 1.42 (I)
1.48 ≦ n _d ≦ 1.56 (II)
(In formulas (I) and (II), n _d , n _C , and n _F represent the refractive indices for d line, C line, and F line, respectively.)
The resin for optical materials according to claim 5, wherein the resin satisfies the condition represented by: An optical element comprising: a first optical member made of a first optical material; and a second optical member made of a second optical material disposed on the first optical member,
A diffraction grating is formed at the interface between the first optical member and the second optical member,
The refractive index of the first optical material for d-line, C-line and F-line at 22.5 ° C. and the refractive index of the second optical material for d-line, C-line and F-line at 22.5 ° C. Formulas (III) and (IV) below:
n _1d <n _2d (III)
_{n 1F -n 1C> n 2F -n} 2C (IV)
(In the formula (III), n _1d and n _2d represent the refractive indexes of the first and second optical materials with respect to the d-line, respectively, and in the formula (IV), n _1C and n _1F represent the first optical material of the first optical material, respectively. Refractive indexes for C line and F line are shown, and n _2C and n _2F are refractive indexes for C line and F line of the second optical material, respectively.
Meets the conditions
The first optical material is a resin for optical materials obtained by curing a resin precursor composition containing the cage polysilsesquioxane derivative according to claim 1 or 2.
An optical element.   The optical element according to claim 7, wherein the first optical material is the resin for optical materials according to claim 5. Following formula (3):

(And in the formula ^{(3), R 111 ~R 113} , R 121 ~R 123, R 131 ~R 133, R 141 ~R 143, R 151 ~R 153, R 161 ~R 163, R 171 ~R 173, Two or more of R ^{181 to} R ¹⁸³ are hydrogen atoms, and the remaining groups are alkyl groups having 1 to 3 carbon atoms.)
A cage-type polysilsesquioxane represented by
Following formula (4)

(In Formula (4), X is a C1-C3 alkyl group, and m and n are the integers of 0-5 each independently.)
A diphenylacetylene compound represented by:
An (meth) acrylic acid alkenyl compound;
The method for producing a cage-type polysilsesquioxane derivative according to claim 1, wherein: Forming a diffraction grating shape on the first optical member made of the first optical material;
Forming a second optical member made of a second optical material on the diffraction grating shape;
A method for producing an optical element comprising:
The first optical material is a resin for optical materials obtained by curing a resin precursor composition containing the cage polysilsesquioxane derivative according to claim 1 or 2,
The second optical material is a refractive index of the first optical material with respect to d-line, C-line and F-line at 22.5 ° C., and d-line and C-line of the second optical material at 22.5 ° C. , The refractive index with respect to the F-line is represented by the following formulas (III) and (IV):
n _1d <n _2d (III)
_{n 1F -n 1C> n 2F -n} 2C (IV)
(In the formula (III), n _1d and n _2d represent the refractive indexes of the first and second optical materials with respect to the d-line, respectively, and in the formula (IV), n _1C and n _1F represent the first optical material, respectively. Refractive indexes for C line and F line are shown, and n _2C and n _2F are refractive indexes for C line and F line of the second optical material, respectively.
Satisfying the condition represented by
A method for manufacturing an optical element.

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