KR20100124831A

KR20100124831A - Film in which refractive index modulation is recorded

Info

Publication number: KR20100124831A
Application number: KR1020107023451A
Authority: KR
Inventors: 야스시 다카마츠; 유고 야마모토; 유이치 이토
Original assignee: 미쓰이 가가쿠 가부시키가이샤
Priority date: 2008-07-10
Filing date: 2009-07-09
Publication date: 2010-11-29
Also published as: WO2010004753A1; JP5315344B2; JPWO2010004753A1; KR101278860B1; TWI456785B; TW201004002A

Abstract

The present invention provides a film in which refractive index modulation is recorded, that is, a film having a refractive index distribution. Specifically, in the surface of the film which has a 1st area | region which has a 1st refractive index, and a 2nd area | region which has a 2nd refractive index, and a said 2nd area is disperse | distributed to the said 1st area | region, and recorded the said refractive index modulation, The average value of the circle equivalent diameter of the said 2nd area | region is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | region is 5 micrometers or more and 500 micrometers or less, and the refractive index difference ((triangle | delta)) of a 1st area | region and a 2nd area | region n) is 0.001 to 2.0. The film of the present invention can be produced without requiring complicated processing techniques such as etching processing.

Description

FILM IN WHICH REFRACTIVE INDEX MODULATION IS RECORDED}

The present invention relates to a film recording refractive index modulation, a method of manufacturing the same, and a light emitting device having the same.

Optical elements such as microlenses are widely applied to CCDs, CMOS optical devices, organic ELs, LED light emitting devices, and the like, or applications have been studied. Usually, in order to form a lens on an optical device or a light emitting device, it is necessary to process etching etc. For example, in order to form a convex lens on an optical device or a light emitting device, in order to reduce the radius of curvature of spherical processing, deep etching must be performed in addition to the lens portion, and the processed layer must be grown very thick. .

Therefore, although some diffractive optical elements such as planar Fresnel lenses and the like are formed on the light emitting surface, processing by lithography, etching, or the like is required, and very advanced etching techniques are required. Various methods have been proposed to avoid the etching process, but there is still a problem in terms of practicality.

Although a method of producing a refractive index distribution without using etching is disclosed (see Patent Document 1), thermal firing of 250 ° C to 450 ° C is required in the final process of forming a methyl silsesquioxane (MSQ) film by polysilazane method. However, it is not applicable to devices that are weak to heat.

Although a method for producing a refractive index distribution lens using two types of monomers has been disclosed (see Patent Document 2), it is a two-step process using radical polymerization, and polymerization is performed while immersing the substrate in styrene in the second step. Complex process is required.

Although the manufacturing method of a microlens array is disclosed (refer patent document 3), there exists a process of heating to a photoresist process and a heat distortion temperature, and when using a normal photoresist material, the heating process requires 150 degreeC or more, It cannot be used for devices that are weak to heat.

Although a method of forming a microlens by spraying a liquid material is disclosed (Patent Document 4), control of the hydrophilicity and hydrophobicity of the substrate and the liquid material is required. Therefore, it is necessary to apply | coat a hydrophobic layer by a fluorine-type material to a board | substrate, a process is complicated, and there exists a possibility of contamination to another member.

On the other hand, the method (refer patent document 5) which manufactures a hologram by exposing and heat-processing the photosensitive recording material which consists of a thermosetting epoxy oligomer, a radically polymerizable aliphatic monomer, a photoinitiator, and a sensitizing dye; A method of producing a hologram by subjecting a photosensitive composition composed of a radical polymerizable compound, a cationic polymerizable compound, a binder polymer, a photosensitive dye and a photocationic polymerization initiator to be exposed by the first light and the second light ( Patent Document 6) is reported.

Moreover, an optical waveguide is produced by forming a core part by exposing the composition containing two types of photocurable resins from which a curable wavelength differs by a 1st light, and then exposing with a separate light to form a clad part. The method is reported (refer patent document 7 and 8).

Japanese Patent Laid-Open No. 2005-57239 Japanese Patent Publication No. 1993-224305 Japanese Patent Laid-Open No. 1994-194502 Japanese Patent Publication No. 2006-23683 Japanese Patent Laid-Open No. 1995-6161 Japanese Patent Laid-Open No. 2004-138686 Japanese Patent Publication No. 2000-347043 Japanese Patent Publication No. 2003-177259

An object of the present invention is to provide a film on which refractive index modulation is recorded, that is, a film having a refractive index distribution, without requiring complicated processing techniques such as etching processing. In particular, the present invention provides an optical resin film having a high function such as directivity control of light. Directivity control of light means the property of controlling the advancing direction of light to a desired direction. If the directivity of the light can be controlled, the extraction efficiency of the light from the light emitting device can be improved.

That is, the 1st invention of this invention relates to the film shown below.

[1] A film having a first region having a first refractive index and a second region having a second refractive index, wherein the second region is dispersed in the first region,

The average value of the equivalent circle diameter of the said 2nd area | region in the said film surface is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,

The film has a refractive index difference Δn between the first area and the second area of 0.001 to 2.0.

[2] The film according to [1], wherein the surface roughness Ra measured by AFM (atomic force microscope) is 0.01 to 1 µm.

[3] The film according to [1], wherein the second region is substantially cylindrical.

[4] The film according to [1], wherein the refractive index is modulated gradiently from the first region to the second region.

[5] The film according to [1], which is a refractive index distribution microlens.

[6] The film according to [1], wherein any one of the first region and the second region contains a resin having a fluorene skeleton.

[7] The film according to [1], in which one of the first region and the second region contains an epoxy resin.

2nd invention of this invention is related with the refractive index modulation recording composition shown below, and the manufacturing method of the film which recorded refractive index modulation.

[8] an acrylic compound having a refractive index of nD [A]; Epoxy compounds having a refractive index of nD [B] and no optical radical polymerizable functional group; Optical radical initiators; And a thermosetting accelerator,

ND [B] -nD [A] | is 0.001 or more and 2.0 or less,

The composition for refractive index modulation recording whose viscosity in 25 degreeC measured with the E-type viscometer is 0.01 Pa.s or more and 100 Pa.s or less.

[9] The composition according to [8], wherein the acrylic compound has a fluorene skeleton and the molecular weight of the acrylic compound is 100 or more and 1000 or less.

[10] The composition of [8], further comprising a thermal radical initiator.

[11] The composition according to [8], which is a film form.

[12] a first step of preparing a composition according to [8], a second step of positionally irradiating an active energy ray to the composition, and a third step of heating the composition to which the active energy ray is irradiated; As a method for producing a film recording refractive index modulation,

The film recording the refractive index modulation,

A first region having a first refractive index and a second region having a second refractive index, wherein the second region is dispersed in the first region,

The average value of the equivalent circle diameter of the said 2nd area | region in the film surface of the said film is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,

The refractive index difference (Δn) between the first region and the second region is 0.001 to 2.0.

[13] The production method according to [12], wherein the composition in the first step is disposed in a thin film on the organic EL device.

[14] A method for producing a film in which refractive index modulation is recorded, comprising a first step of preparing a composition according to [8] and a second step of positionally irradiating an active energy ray to the composition.

The film recording the refractive index modulation,

A third invention of the present invention relates to a light emitting device and a manufacturing method thereof.

[15] A light emitting device comprising a panel substrate on which an organic EL element is disposed, an opposing substrate mating with the panel substrate, and a sealing layer interposed between the panel substrate and the opposing substrate to seal the organic EL element. ,

The sealing layer,

The average value of the equivalent circle diameter of the said 2nd area | region in the surface of the said sealing layer is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,

The light emitting device of which the refractive index difference Δn between the first region and the second region is 0.001 to 2.0.

[16] A method of manufacturing the light emitting device according to [15], comprising the step of adhering the film according to [1] to an organic EL element and a step of curing the bonded film.

Although the film on which the refractive index modulation of the present invention is recorded can be produced without requiring a complicated process such as etching, the film can have a function such as controlling the directivity of light. Therefore, the film of this invention can raise light extraction efficiency, for example, and can use as a part material of a light emitting device (for example, organic electroluminescent element), and can raise the light extraction efficiency of a device.

In addition, a desired refractive index distribution can be formed in the film of the present invention, for example, a cylindrical, concentric, or lattice-shaped refractive index distribution can be formed. In addition, the high refractive index region and the low refractive index region may be alternately formed in the film of the present invention. The film recorded with such refractive index modulation can also obtain the same effect as the light emitting device equipped with the Fresnel lens, and can also take out the light from the light emitting device or disperse it to the outside.

Of course, since the film on which the refractive index modulation of the present invention is recorded can be produced by a simple manufacturing process, it is possible to reduce the size and size of a light emitting device including the same. Moreover, since the film of this invention is comprised substantially from an organic substance, compared with the film in which the frame | skeleton is formed with an inorganic substance, it is less in weight, and can be used suitably as a sealing member of light emitting devices, such as an organic EL element.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the representative example of the film in which refractive index modulation was recorded.
FIG. 2 is a diagram showing a photomask used in Example 1. FIG.
3 is a refractive index modulation map of a film on which refractive index modulation obtained in Example 1 is recorded.

The film of this invention is a member which consists essentially of organic substance on a film | membrane, may be a film single body, and may be a thin film and a layer formed in the base | substrate (including a light emitting element etc.). "Substantially consists of organic substance" means that a skeleton is formed by carbon-carbon bond in the range which does not reduce the effect of this invention, and the shape of the said member is maintained. Although the refractive index modulation is recorded, the film of this invention is not a member which forms optical interference fringes, such as a hologram, but a member which does not have wavelength dependence.

The film of this invention has a 1st area | region which has a 1st refractive index, and a 2nd area | region which has a 2nd refractive index. The first region acts as a base material, and the second region is dispersed in the first region.

The difference between the first refractive index and the second refractive index may be 0.001 to 2.0, and preferably 0.01 to 2.0. The first refractive index and the second refractive index may be different, and any one may be large. Moreover, from the viewpoint of the ease of manufacture of the film of the present invention, the difference between the first refractive index and the second refractive index is preferably 0.001 to 1.0, more preferably 0.001 to 0.5. The difference in refractive index may be a difference between the maximum refractive index in the region having the larger refractive index and the minimum refractive index in the region having the smaller refractive index. The refractive index may be measured using an interference microscope. Specifically, it measures with reference to the measuring principle described in "APPLIED OPTICS, vol. 41, No. 7, 1308 (2002)" as described in the Example mentioned later.

As mentioned above, it is preferable that the film of this invention does not have wavelength dependence (it forms an interference fringe, or does not form a diffraction grating). Therefore, it is preferable that the 2nd area | region dispersed in the 1st area | region has a certain magnitude. Specifically, it is preferable that the average value of the equivalent circle diameter of the 2nd area | region in the surface of a film is 5 micrometers or more and 500 micrometers or less. Moreover, it is preferable that the average of the space | interval of 2nd area | regions in the surface of a film is 5 micrometers or more and 500 micrometers or less. When the average value of the circle equivalent diameter of a 2nd area | region and the average of the space | interval between 2nd area | regions are smaller than 5 micrometers, an interference fringe may be formed.

As described later, the refractive indices of the first region and the second region may be modulated in a gradient. In that case, the boundary between the first region and the second region on the film surface is arbitrarily set in the region where the refractive index is modulated gradiently; What is necessary is just to calculate the magnitude | size (circle equivalent diameter) of a 2nd area | region, and the space | interval between 2nd area | regions based on the set boundary.

When using the film of this invention as a microlens, it is preferable that a 2nd area penetrates a 1st area, ie, a 2nd area penetrates in the thickness direction of a film. If the second region penetrates, the direction of light can be controlled in the penetrating direction, so that the directivity of the light can be obtained. And if the penetrating second region is substantially circumferential, formation of interference fringes is suppressed.

In order to raise light extraction efficiency using the film of this invention, it is preferable that 2nd area | region is arrange | positioned in matrix form (lattice form) in a 1st area | region.

1, the typical example of the film of this invention is shown typically. The 1st area | region A which has a 1st refractive index comprises the base material of a film. The second region B having the second refractive index is arranged in a matrix (lattice) on the film surface. Each of the second regions B is substantially cylindrical and penetrates in the thickness direction of the film. The circle equivalent diameter b at the film surface of the second region B is set to about 5 to 500 mu m. Moreover, the shortest space | interval a between 2nd area | region B is also set to about 5-500 micrometers.

Moreover, it is preferable that the surface of the film of this invention is flat. The film of this invention may be provided in the element on a panel substrate or a panel substrate, in order to make arrangement easy. Specifically, the surface roughness Ra of the film is usually 0.01 to 1 µm, and preferably 0.01 to 0.1 µm. As will be described later, since the film of the present invention does not need to be shaped by etching or the like, the film surface can be made flat.

When providing the film of this invention to the light transmission part of a light emitting device (for example, organic electroluminescent element), and improving luminous efficiency, it is preferable that the thickness is 1-200 micrometers, and it is further 1-100 micrometers. desirable. In addition, when a film recorded with refractive index modulation is used as a microlens (refractive index distribution type lens), its lens function can be adjusted to the film thickness. Therefore, what is necessary is just to adjust film thickness according to a desired lens function.

It is preferable that either one of the 1st area | region and 2nd area | region which comprise the film of this invention is resin containing a fluorene skeleton. By introducing a fluorene skeleton, the refractive index can be increased. Therefore, when either one of a 1st area | region and a 2nd area | region is made into resin containing a fluorene frame | skeleton, the refractive index difference with another area tends to arise.

Moreover, either one of the 1st area | region and 2nd area | region which comprise the film of this invention may contain the epoxy resin. As mentioned later, although the film of this invention is obtained by photopolymerizing the composition containing photopolymerizable resin and thermosetting resin (epoxy resin), the film (half-cure film) in which a thermosetting resin is uncured state is also this invention. It is one sun of the film. Of course, the film of the state which hardened thermosetting resin is also one aspect of the film of this invention.

The film which recorded the refractive index modulation of this invention can be used for arbitrary uses as an optical device. For example, it can be used as a micro lens of an optical element. When using the film which recorded the refractive index modulation as a lens, it is preferable that the refractive index changes gradually from 1st area | region to 2nd area | region.

A lens is a transparent body which exhibits the refractive action of light, and can control the direction of the light passing therethrough, and can diffuse or converge light, for example. The lens in the present invention is called a refractive index distribution lens, unlike a spherical lens. The refractive index distribution lens refers to a transparent member whose refractive index is modulated gradiently from a certain point toward the surroundings. That is, when using the film which recorded refractive index modulation as a refractive index distribution type lens, it is preferable that the refractive index of a 1st area | region or a 2nd area | region is changing gradient.

In particular, when the circumferential second region penetrates through the first region serving as the base material, the refractive index of the second region can be used as a refractive index distributed rod lens if the refractive index of the second region is modulated in a radial direction. At this time, if the second region is dispersed in a matrix, it can be used as a refractive index distributed rod lens array (see Fig. 1).

Since the light incident from the lens end face of the refractive index distributed lens has a sinusoidal curve, an equal magnification upright image can be obtained by adjusting the rod length (here, the thickness of the film thickness). Therefore, the refractive index distributed rod lens (array) can be utilized as a lens for facsimile, scanner, copier, electronic blackboard, LED printer and optical fiber communication.

Moreover, when the film which recorded the refractive index modulation of this invention is used, it becomes possible to take out the light which generate | occur | produced from the light emitting device efficiently. Therefore, the luminous efficiency of a light emitting device can be improved by providing the film which recorded the refractive index modulation of this invention in the passage part of the light which a light emitting device emits.

The light extraction efficiency of the top emission organic electroluminescent device is about 20%. One of the causes of lowering the light extraction efficiency is reflection at the interface between the organic electroluminescent element and the sealing film sealing it; Reflection at the interface between the sealing film and the glass substrate on the outside. The sealing film prevents the ingress of moisture or oxygen into the organic electroluminescent element and may be made of a resin or the like.

Therefore, by making the sealing film which seals a top emission organic electroluminescent element into the film which recorded the refractive index modulation of this invention, sealing performance can be obtained and light extraction efficiency can be raised further. That is, by controlling the advancing direction of the light emitted from the light emitting layer of the organic electroluminescent element with the film of the present invention, the reflection at the interface with the glass substrate is suppressed and the light extraction efficiency is increased.

For example, the organic electroluminescent element disposed on the panel substrate is covered with the above "half cure film (film only for photopolymerization)" and heated, thereby forming a sealing film of the organic electroluminescent element and recording the refractive index modulation. The formed film can also be formed. An opposing substrate is disposed on the film.

The film recorded with the refractive index modulation of the present invention comprises the steps of 1) preparing a composition (composition for refractive index modulation) containing a photopolymerizable resin and a thermosetting resin, and 2) irradiating an active energy ray to the composition selectively. It may include the step, and further 3) heating.

It is preferable that the photopolymerizable resin contained in the refractive index modulation recording composition contains an acrylic compound. Although an acryl compound will not be specifically limited if it is a compound containing an acryl group or methacryl group, It is preferable to have a fluorene skeleton. As described above, the refractive index is easily increased by introducing a fluorene skeleton. If refractive index can be improved, the refractive index difference with the epoxy compound contained in the thermosetting resin mentioned later can be enlarged. In addition, the refractive index can be increased by introducing a sulfur element or a halogen element into the resin. In order to maintain transparency, it is preferable to introduce elemental sulfur.

Examples of the acrylic compound having a fluorene skeleton include 9,9-bis (4- (meth) acryloyloxyphenyl) fluorene; 9,9-bis (4- (meth) acryloyloxymethoxyphenyl) fluorene; 9,9-bis [4- (2- (meth) acryloyloxyethoxy) phenyl] fluorene; 9,9-bis [4- (meth) acryloyloxy-3-methylphenyl] fluorene; 9,9-bis [4- (meth) acryloyloxymethoxy-3-methylphenyl] fluorene; 9,9-bis [4- (2- (meth) acryloyloxyethoxy) -3-methylphenyl] fluorene; 9,9-bis (4- (meth) acryloyloxy-3-ethylphenyl) fluorene; 9,9-bis (4- (meth) acryloyloxymethoxy-3-ethylphenyl) fluorene; 9,9-bis [4- (2- (meth) acryloyloxyethoxy) -3-ethylphenyl] fluorene; 9,9-bis [4- (2- (meth) acryloyloxypropoxy) -3-ethylphenyl] fluorene; 9,9-bis [4- (3- (meth) acryloyloxy-2-hydroxy) propoxyphenyl] fluorene; 9,9-bis [4- (3- (meth) acryloyloxy-2-hydroxy) propoxy-3-methylphenyl] fluorene; 9,9-bis {4- [2- (3-acryloyloxy-2-hydroxy-propoxy) -ethoxy] phenyl} fluorene and the like.

The acrylic compound which has a fluorene skeleton may be an oligomer of the dimer or trimer degree of the said exemplary compound.

It is preferable that the molecular weight of an acryl compound is 100 or more and 1000 or less. This is for imparting at least a certain degree of photopolymerization reactivity to the acrylic compound.

It is preferable that a photopolymerizable resin contains an optical radical initiator. The kind of optical radical initiator is not specifically limited, What is necessary is just to select suitably according to the kind of acryl compound. Examples of the optical radical initiators include benzoin compounds, acetophenones, benzophenones, thioxanthones, α-acyl oxime esters, phenylglyoxylates, benzyls, azo compounds, diphenyl sulfide compounds, and acyl. Phosphine oxide compounds, organic pigment compounds, iron-phthalocyanine compounds, benzoin compounds, benzoin ethers, anthraquinones and the like.

It is preferable that the quantity of the optical radical initiator contained in photopolymerizable resin is 0.1 mass part or more and 100 mass parts or less with respect to 100 mass parts of acrylic compounds.

On the other hand, it is preferable that the thermosetting resin contained in the refractive index modulation recording composition contains an epoxy compound. The epoxy compound is required not to have optical radical polymerizability. Therefore, it is preferable that an epoxy compound does not have an optical radical polymerizable functional group, for example, a carbon-carbon unsaturated bond (acrylic group etc.).

It is preferable that a thermosetting resin contains the thermosetting accelerator. The kind of thermosetting accelerator is not specifically limited, What is necessary is just to select suitably according to the kind of epoxy compound. Examples of thermal curing accelerators include imidazole compounds and amine compounds. Examples of imidazole compounds include 2-ethyl-4-methylimidazole. Examples of the amine compound include trisdimethylaminomethylphenol and the like. It is preferable that the quantity of the thermosetting accelerator contained in a thermosetting resin is 0.1 mass part-100 mass parts with respect to 100 mass parts of epoxy compounds.

The thermosetting resin may contain acid anhydride. From the thermosetting resin containing acid anhydride, the resin hardened | cured material with high transparency is obtained. The acid anhydride contained in the thermosetting resin is required not to have photopolymerizable property, and therefore does not have a photopolymerizable functional group. The acid anhydride is preferably an acid anhydride of an aromatic carboxylic acid. Examples of the acid anhydride include phthalic anhydride, tetrahydro phthalic anhydride, methyltetrahydro phthalic anhydride, hexahydro phthalic anhydride, methylhexahydro phthalic anhydride, trimellitic anhydride, Hexachloroendomethylenetetrahydrophthalic anhydride, benzophenonetetracarboxylic acid anhydride and the like.

The thermosetting resin may contain the thermal radical initiator. A thermal radical initiator superposes | polymerizes the photopolymerizable compound which remained without superposition | polymerization by light irradiation mentioned later by heating, and finally prevents a photopolymerizable compound from remaining. Examples of thermal radical initiators include conventionally known organic peroxides and azo compounds. Usually depending on heating conditions, it is preferable that a thermal radical initiator is a compound whose half life temperature is 120 degrees C or less for 10 hours. Examples of thermal radical initiators include cumylperoxy neodecanoate, di-n-propylperoxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, t-butylperoxy neodecanoate, 2,4 Dichlorobenzoyl peroxide, lauroyl peroxide, acetyl peroxide, t-butylperoxy-2-ethylhexanoate, benzoyl peroxide, t-butylperoxy isobutyrate, t-butylperoxylaurate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxyisopropylcarbonate, t-butylperoxy acetate, t-butylperoxybenzoate, methyl ethyl ketone peroxide, diQ Milper oxide, t-butyl cumyl peroxide, etc. Examples of azo compounds include azobisisobutyronitrile, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), azobis (methylbutylnitrile) and the like. do. In the present invention, one type of thermal radical initiator may be used, or two or more types may be used in combination.

The composition of the present invention comprises a photopolymerizable resin containing an acrylic compound and a thermosetting resin containing an epoxy compound, but the difference between the refractive index nD [A] of the acrylic compound and the refractive index nD [B] of the epoxy compound is 0.001 or more. It is preferable that it is 2.0 or less. When an acrylic compound or an epoxy compound is a mixture of 2 or more types of compounds, the refractive index of this mixture is set to nD [A] or nD [B].

Either nD [A] or nD [B] may be large. However, as mentioned above, when nF [A] becomes large when a fluorene skeleton is introduce | transduced into an acryl compound, it is preferable to set nD [A]> nD [B].

Although the composition for refractive index modulation recording of this invention contains the photopolymerizable resin containing an acrylic compound and the thermosetting resin containing an epoxy compound, content of the epoxy compound with respect to 100 mass parts of acrylic compounds is 10 mass parts or more and 1000 mass parts. It is preferable that it is parts or less.

Although the viscosity of the composition for refractive index modulation recording is not particularly limited, in the step of irradiating an active energy ray described later, it is preferable that the photopolymerizable resin is moved to the irradiation region and polymerized selectively in the irradiation region. When the viscosity of the composition is too high, movement of the photopolymerizable resin to the irradiation region is suppressed; If the viscosity is too low, the photopolymerizable resin that has moved to the irradiation region does not stay in the irradiation region and is not selectively polymerized. Therefore, it is preferable that it is 0.01-100 Pa.s, and, as for the viscosity (25 degreeC) measured with the E-type viscosity meter of a composition, it is more preferable that it is 0.01-50 Pa.s.

The method for producing a film recording the refractive index modulation of the present invention includes the step of irradiating selectively the active energy ray to the above-mentioned composition. What is necessary is just to make the active energy ray to irradiate be an energy ray which can superpose | polymerize photopolymerizable resin. Examples of active energy rays include ultraviolet rays, electron beams, visible rays, infrared rays, and the like.

It is preferable that the composition to which an active energy ray is irradiated is a thin film form. A thin film composition is a film-form composition, the coating film of the composition apply | coated and formed on the board | substrate, or the thin film shape composition clamped on two glass plates and hold | maintained. When sandwiching and holding two glass plates, a release film can also be arrange | positioned between a glass plate and a thin film, and the film single piece can be taken out easily by this. What is necessary is just to adjust the thickness of a thin film composition so that the film thickness after irradiation of an active energy ray may be 1-200 micrometers. If the thickness of the thin-film composition is too thick, light does not sufficiently propagate to the inside of the film, thereby degrading the recordability of the refractive index modulation.

In order to irradiate an active energy ray selectively, the composition may be irradiated with the mask which provided the desired pattern, and may be irradiated by scanning.

Although the area of each irradiation area is arbitrary, since the film which recorded the refractive index modulation of this invention does not form interference fringes and does not have wavelength dependence, for example, the circle equivalent diameter of the opening part of a mask is 5 micrometers or more and 500, for example. It is preferable to set it as micrometer or less. In addition, it is preferable that the shape of the opening of the mask (the shape of the irradiation area) is circular. If the shape has a vertex (triangle or rectangle), the vertex may form an interference fringe.

When the active energy ray is selectively irradiated to the thin film-like composition, the photopolymerizable resin polymerizes in the irradiation region. Then, the unpolymerized photopolymerizable resin which exists in the periphery of an irradiation area flows into an irradiation area, and the thermosetting resin which exists in an irradiation area flows out from an irradiation area. The photopolymerizable resin introduced into the irradiation region is also polymerized by the active energy ray.

In this way, a film in which the photopolymerized resin is selectively localized in the irradiation area is obtained. This film may be called a "half cure film", and a half cure film is also one aspect of the film of this invention.

The obtained half-cure film mainly contains uncured thermosetting resin outside the irradiation area. Then, the thermosetting resin is cured by heating the half cure film. At this time, if a thermal radical initiator is contained in thermosetting resin, a part of photopolymerizable resin which was not able to superpose | polymerize by light irradiation can also be thermally polymerized, and it can also prevent that a monomer remains in the film obtained.

By heating of the half-cure film, the polymer of photopolymerizable resin is unevenly distributed in the irradiation area, and the film which hardly squeezed the hardened | cured material of thermosetting resin is obtained in the other area | region. As described above, since the refractive index of the acrylic compound contained in the photopolymerizable resin and the refractive index of the epoxy compound included in the thermosetting resin are made different, the refractive index of the photopolymerized resin and the refractive index of the thermosetting resin are also almost different. Have the same degree of difference. As a result, a film in which refractive index modulation is recorded is obtained.

[Example]

Each component used by each Example and the comparative example is as follows.

(Component of Photopolymerizable Resin)

Fluorene type acrylate resin: 9,9-bis (4- (meth) acryloyloxyphenyl) fluorene (oxol EA-O200, the product made by Osaka Chemical)

Acrylate resin (without fluorene skeleton): triethylene glycol dimethacrylate

Photoinitiator: Irgacure 651 (made by Chiba Specialty Chemicals)

(Component of Thermosetting Resin)

Bisphenol F type epoxy resin: YL-983U (product made in Japan epoxy resin company)

Thermal curing accelerator: tris dimethylaminomethyl phenol (JER cure 3010, product made in Japan epoxy resin company)

Acid anhydride (curing agent): A mixture of hexahydro phthalic anhydride and methylhexahydro phthalic anhydride (Licaside MH-700, manufactured by Shin-Nihon Corporation)

Thermal initiator: Perbutyl O (made by Nichiyu Corporation)

The composition prepared by each Example or the comparative example was sandwiched between two glass plates (60x60x1.3mm), and it fixed with the kapton tape and made it the test piece. The thickness of the test piece was set to 12 micrometers by arrange | positioning the aluminum foil spacer between two glass plates.

The produced test piece was exposed to light for 10 ^second by the light intensity of 10 mW / cm <^2> using the UV irradiation machine (LIGHTNINGCURE LC8 by Hamamatsu Photonics) through the photomask (refer FIG. 2). The photomask used is a member in which holes are formed in a matrix in a central region (10 × 10 mm) of 50 mm × 50 mm, as shown in Fig. 2A. As shown in Fig. 2B, the pore diameter of the hole is 30 mu m, the distance between the centers of the holes is 37.6 mu m, and the spacing between the holes is 7.6 mu m.

Thereafter, the test piece was subjected to an after-cure for 2 hours in an oven at 80 ° C. to obtain a film in which refractive index modulation was recorded.

The composition obtained by each Example or the comparative example, and the film in which refractive index modulation was recorded were evaluated about the following items.

(1) transparency

The composition was visually observed, and the film in which the film was a transparent and uniform solution and the refractive index modulation was similarly observed visually was evaluated as a case where the transparent case was ○ and the case where it was not transparent (cloudy or the like) was evaluated as x.

(2) viscosity

The viscosity of the composition at 25 degreeC was measured using the E-type viscosity meter (digital rheometer type DII-III ULTRA by BROOKFIEL).

(3) recordability

It was observed by the optical microscope whether the shape of the hole of the mask was recorded on the film. The case where it was recorded was (circle) and the case where it was recorded but not recorded a little, (triangle | delta) and the case where it was slightly recorded were (triangle | delta) and the case where it was not recorded was made into x.

(4) refractive index modulation of a film recording refractive index modulation

The refractive index modulation (difference between the refractive index of an irradiation area and the refractive index of a non-irradiation area) was measured by the interference microscope (transmission type phase shift laser microscopic interference measurement apparatus, FK optical laboratory, Inc.). Incident light was He-Ne laser (wavelength: 633 nm). The principle of this measurement is described in APPLIED OPTICS, vol. 41, No. 7, 1308 (2002). Difference (DELTA) n of refractive index was made into the value of the difference between the largest refractive index and the minimum refractive index in the film which recorded refractive index modulation.

Example 1

50 mass parts of oxol EA-O200, 25 mass parts of YL-983U, and 25 mass parts of lycaside MH-700 were charged to the flask, and it mixed while heating. Then, it cooled to room temperature and added and mixed 3 mass parts Irgacure 651 and 0.5 mass part perbutyl O. Furthermore, 1 mass part JER cure 3010 was added, and it stirred at room temperature, and obtained the composition. The test piece was produced from the obtained composition, the refractive index modulation was further recorded, and the film which recorded the refractive index modulation was produced.

[Examples 2 to 5]

The film which recorded refractive index modulation was obtained like Example 1 except having mix | blended ratio (mass part) of each component as showing in the following table | surface.

The evaluation result of the composition produced in Examples 1-5 and the film which recorded refractive index modulation is shown in the following table | surfaces.

In addition, the surface roughness of the glass plate used for test piece preparation was measured by AFM. The centerline average roughness Ra was 0.01 µm and the maximum height Rmax was 0.35 µm. The surface roughness of glass was transferred to the surface of the produced film, and had the same roughness.

In addition, the refractive index modulation map of the film which recorded the refractive index modulation obtained in Example 1 is shown in FIG. It can be seen that portions having different refractive indices (high refractive index) are arranged in a matrix.

[Examples 6 to 7]

Example 1 was used instead of oxol EA-O200, "triethylene glycol dimethacrylate" which is an acrylate resin which does not have a fluorene structure, and the compounding ratio of each component is shown to the following table | surface. In the same manner as described above, a film on which refractive index modulation was recorded was obtained.

In Examples 6 and 7, the recordability evaluation result was Δ. This is considered to be because the difference in refractive index did not increase because the fluorene skeleton was not contained in the acrylate resin used as the photopolymerizable resin.

This application claims the priority based on Japanese Patent Application No. 2008-180578 for which it applied on July 10, 2008. All the content described in the said application specification and drawing is integrated in this specification.

[Industry availability]

The refractive index modulated recording film of the present invention may have a function such as controlling the directivity of light. Therefore, the refractive index modulation recording film of the present invention can improve the light extraction efficiency, for example, and when used as a part of a light emitting device (for example, an organic electroluminescent element), the light extraction efficiency of the device can be improved. .

Claims

A film having a first region having a first refractive index and a second region having a second refractive index, and wherein the second region is dispersed in the first region,
The average value of the equivalent circle diameter of the said 2nd area | region in the said film surface is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,
The film has a refractive index difference Δn between the first area and the second area of 0.001 to 2.0.

The method of claim 1,
The film whose surface roughness Ra is 0.01-1 micrometer measured by AFM (atomic force microscope).

The method of claim 1,
A film in which the second region is approximately cylindrical.

The method of claim 1,
The film whose refractive index is modulated gradiently from the first region to the second region.

The method of claim 1,
A film that is a refractive index distributed microlens.

The method of claim 1,
The film containing resin in which any one of a 1st area | region and a 2nd area | region has a fluorene skeleton.

The method of claim 1,
Either one of a 1st area | region and a 2nd area | region contains an epoxy resin.

An acrylic compound having a refractive index of nD [A],
Epoxy compounds having an index of refraction nD [B] and no optical radical polymerizable functional group,
Optical radical initiator, and
Thermosetting accelerator
As a composition comprising a,
ND [B] -nD [A] | is 0.001 or more and 2.0 or less,
The composition for refractive index modulation recording whose viscosity in 25 degreeC measured with the E-type viscometer is 0.01 Pa.s or more and 100 Pa.s or less.

The method of claim 8,
The acrylic compound has a fluorene skeleton and the molecular weight of the acrylic compound is 100 or more and 1000 or less.

The method of claim 8,
The composition further comprises a thermal radical initiator.

The method of claim 8,
A composition in the form of a film.

A refractive index modulation comprising a first step of preparing the composition of claim 8, a second step of positionally irradiating the active energy ray to the composition, and a third step of heating the composition to which the active energy ray is irradiated As a manufacturing method of the recorded film,
The film recording the refractive index modulation,
A first region having a first refractive index and a second region having a second refractive index, wherein the second region is dispersed in the first region,
The average value of the equivalent circle diameter of the said 2nd area | region in the said film surface is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,
The refractive index difference (Δn) between the first region and the second region is 0.001 to 2.0.

The method of claim 12,
The said composition in a 1st process is a manufacturing method arrange | positioned in thin film form on organic electroluminescent element.

A method for producing a film with a refractive index modulation comprising a first step of preparing a composition according to claim 8 and a second step of positionally irradiating an active energy ray to the composition,
The film recording the refractive index modulation,
A first region having a first refractive index and a second region having a second refractive index, wherein the second region is dispersed in the first region,
The average value of the equivalent circle diameter of the said 2nd area | region in the said film surface is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,
The refractive index difference (Δn) between the first region and the second region is 0.001 to 2.0.

A light emitting device comprising a panel substrate on which an organic EL element is disposed, an opposing substrate mating with the panel substrate, and a sealing layer interposed between the panel substrate and the opposing substrate to seal the organic EL element.
The sealing layer,
A first region having a first refractive index and a second region having a second refractive index, wherein the second region is dispersed in the first region,
The average value of the equivalent circle diameter of the said 2nd area | region in the surface of the said sealing layer is 5 micrometers or more and 500 micrometers or less, and the average value of the space | interval of said 2nd area | regions is 5 micrometers or more and 500 micrometers or less,
The light emitting device of which the refractive index difference Δn between the first region and the second region is 0.001 to 2.0.

A method of manufacturing the light emitting device according to claim 15,
A method of manufacturing a light emitting device comprising the step of adhering the film according to claim 1 to an organic EL element and the step of curing the adhered film.