TW201302807A - Composition for forming fluorescent sheet - Google Patents

Abstract

This composition-which is for forming a fluorescent sheet and can, at a low cost, provide a fluorescent sheet that exhibits favorable light resistance, has a low light absorbance of visible light, uses a low-cost material, and at the same time has suppressed alteration by means of water of a fluorescent body-contains a composition for film formation, and a particulate fluorescent body that releases fluorescent light by means of irradiation by excitation light. A photocurable compound is used as the composition for film formation. A photocurable (meth)acrylate, preferably a urethane (meth)acrylate, can be cited as the photocurable compound. The result of esterification by means of 2-hydroxypropyl acrylate of the reaction product of a polyol and isophorone diisocyanate can be cited as the urethane (meth)acrylate.

Description

Phosphor sheet forming composition

The present invention relates to a composition for forming a phosphor sheet containing a film-forming composition and a powdery phosphor which emits fluorescence by irradiation of excitation light.

Previously, a phosphor sheet in which a powdery red phosphor that emits red fluorescence by irradiation of blue light and a green phosphor that emits green fluorescence are dispersed in a resin material excellent in visible light transmittance is used. In the industry, it is attempted to emit red light and green light from blue light-emitting diodes (blue LEDs), and to mix them with blue light, thereby obtaining white light (Patent Document 1).

Patent Document 1: Japanese Laid-Open Patent Publication No. 2008-41706

However, when a low-cost general-purpose thermoplastic resin or the like is used as the resin material in such a phosphor sheet, the resin material is yellowed due to blue light, and the light output of the blue LED is lost or emitted. The problem of absorption of light. Further, there is a problem that the phosphor is deteriorated by the moisture infiltrated into the resin material, and a color change occurs in the luminescent color of the phosphor sheet. Therefore, it is necessary to use a polyoxynated resin which is excellent in light resistance and water vapor permeability but high in cost as a resin material, or to sandwich both sides of a phosphor sheet with a high cost glass substrate, but it is also difficult to depress the phosphor sheet. The problem of manufacturing costs.

The present invention has been made to solve the above problems, and an object thereof is to provide a phosphor sheet forming composition capable of obtaining a phosphor sheet at low cost, the phosphor The film uses a material which exhibits good light resistance, low light absorption to visible light, and low cost, and deterioration of the phosphor due to moisture is suppressed.

The present inventors have found that a photocurable compound which exhibits good light resistance and low light absorbability to visible light and can be obtained at low cost is used as a film-forming composition constituting a composition for forming a phosphor sheet. The main component can achieve the above object, thereby completing the present invention.

In other words, the present invention provides a composition for forming a phosphor sheet, which comprises a film-forming composition and a powdery phosphor which emits fluorescence by irradiation of excitation light.

The film-forming composition contains a photocurable compound.

Moreover, the present invention provides a phosphor sheet in which a phosphor layer that emits fluorescence by irradiation of excitation light is sandwiched between a pair of transparent substrates, and the phosphor layer is a fluorescent layer of the present invention. Further, the present invention provides a light-emitting device comprising the phosphor sheet and an excitation light source that emits excitation light for irradiating the phosphor sheet.

In the composition for forming a phosphor sheet of the present invention, the film-forming composition is used in a variety of resins or polymerizable compounds, and is excellent in light resistance and light absorption to visible light as compared with a thermoplastic resin or the like. A resin, and a photocurable compound which can be obtained at relatively low cost. Therefore, according to the phosphor sheet forming composition of the present invention, it is possible to provide a phosphor sheet which is excellent in light resistance, low in light absorbability to visible light, and which suppresses deterioration of a phosphor due to moisture at a low cost. Even if the phosphor sheet is used for a long period of time, the chromaticity shift is small and the luminescence spectrum intensity is reduced.

The composition for forming a phosphor sheet of the present invention contains a film-forming composition and a powdery phosphor which emits fluorescence by irradiation of excitation light.

The film-forming composition contains a photocurable compound. Here, the reason why the photocurable compound is used is that the resin formed during photocuring sufficiently adheres to the surface of the phosphor, exhibits excellent light resistance and lower water absorption ratio than the thermoplastic resin, and can be obtained at low cost. . As a result, deterioration of the phosphor due to moisture can be prevented. Further, in the photocurable compound, a photocurable monomer can be used in combination as a diluent, and therefore it is not necessary to use a solvent such as toluene. Therefore, the concentration of the phosphor and the photocurable compound as the hardening component can be set higher than in the case of using toluene or the like. Therefore, the number of times of application of the composition for forming a phosphor sheet when a phosphor layer having a specific thickness is formed can be reduced.

The photocurable compound constituting the film-forming composition preferably contains a photocurable (meth) acrylate. The photocurable (meth) acrylate has an ester group exhibiting moisture capturing ability. Therefore, by using the photocurable (meth) acrylate, the moisture infiltrated into the phosphor sheet can be further captured, and deterioration of the phosphor due to moisture can be further prevented.

Examples of such a photocurable (meth) acrylate include urethane (meth) acrylate, polyester (meth) acrylate, and epoxy (meth) acrylate. Among these, ethyl urethane (meth) acrylate can be preferably used in terms of heat resistance. Here, "(meth) acrylate" includes acrylate and methacrylate.

As a preferred urethane (meth) acrylate, a Polyol (preferably polyether polyol, polyolefin polyol, polyester polyol or polycarbonate polyol) is used with a hydroxyalkyl (meth) acrylate (preferably 2-hydroxypropyl acrylate) The reactant of the diisocyanate compound (preferably isophorone diisocyanate) is esterified.

In the present invention, when the content of the ethyl urethane (meth) acrylate in the photocurable (meth) acrylate is too small, the adhesion tends to decrease, so that it is preferably photocurable (methyl). The acrylate has at least 10 parts by mass, more preferably at least 30 parts by mass, per 100 parts by mass.

Further, the film-forming composition usually contains a photopolymerization initiator. Examples of such a photopolymerization initiator include a radical photopolymerization initiator, such as an alkylphenol photopolymerization initiator, a mercaptophosphine oxide photopolymerization initiator, and a titanocene photopolymerization initiator. Agent, oxime ester photopolymerization initiator, oxyphenyl acetate photopolymerization initiator, etc.; cationic photopolymerization initiator, such as diazonium photopolymerization initiator, lanthanide photopolymerization initiation Agent, lanthanide photopolymerization initiator, and the like. The amount of use of the photopolymerization initiator is preferably 0.1 to 10 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the photocurable compound.

In the present invention, the fluorescent system uses a phosphor (generally having an average particle diameter of 3 to 20 μm) which emits fluorescence (fluorescence having a wavelength longer than that of the excitation light) by irradiation of excitation light. The phosphor is a sulfide-based phosphor, an oxide phosphor, or a mixed-type phosphor. Here, as the excitation light, light having a wavelength at which fluorescence can be excited by exciting the phosphor to be used can be appropriately selected. In the case where the phosphor sheet emits white light, it is preferred to use blue light having a blue fluorescent peak having a wavelength of 440 to 490 nm. As the light source of blue light, a known blue LED is preferably used.

Examples of the phosphor include an oxide phosphor having a red fluorescent peak having a wavelength of 590 to 620 nm by irradiation with blue excitation light, preferably CaS:Eu, (BaSr) ₃ SiO ₅ :Eu Or a vulcanized fluorescent body having a green fluorescent peak having a wavelength of 530 to 550 nm by irradiation with blue excitation light, preferably SrGa ₂ S ₄ :Eu.

Further, as the phosphor, a mixture of the above-described phosphors can also be used. In this case, in order to make the phosphor sheet emit white light, it is preferable to use an oxide phosphor having a red fluorescent peak having a wavelength of 590 to 620 nm by irradiation with blue excitation light, and by using blue A mixed phosphor of a sulfide-based phosphor having a green fluorescent peak having a wavelength of 530 to 550 nm irradiated with color excitation light. A combination of particularly good is a mixed phosphor that emits red-fluorescent (BaSr) ₃ SiO ₅ :Eu and green-fluorescent SrGa ₂ S ₄ :Eu.

In the present invention, when the mixing ratio of the phosphor to the film-forming composition is too small, the coating film becomes thick and the amount of the solvent to be used tends to increase. When the amount is too large, the coating film becomes thin and colored. The degree of unevenness of the degree of the film is preferably from 1 to 10 parts by mass, more preferably from 3 to 6 parts by mass, per 100 parts by mass of the film-forming composition.

In the composition for forming a phosphor sheet of the present invention, other light-transmitting compounds such as (meth)acrylic monomers and oligomers, coloring pigments, and the like may be blended as needed within the range in which the effects of the present invention are not impaired. .

The composition for forming a phosphor sheet of the present invention can be prepared by mixing a film-forming composition with a powdery phosphor by a conventional method.

Next, a phosphor sheet using the composition for forming a phosphor sheet of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the phosphor sheet of the present invention is a phosphor sheet 10 in which a phosphor layer 1 which emits fluorescence by irradiation of excitation light is sandwiched between a pair of transparent substrates 2 in a single layer. The phosphor layer 1 is obtained by forming the above-described composition for forming a phosphor sheet of the present invention.

1 shows an example in which the phosphor layer 1 is a single layer. As shown in FIG. 2, a laminated phosphor layer of a two-layer structure in which two layers of phosphor layers 1a and 1b are laminated via a transparent spacer 3 may be used. 20. In this case, it is also sandwiched between a pair of transparent substrates 2a, 2b. By forming the two-layer structure in the above manner, the phosphors which are easily reacted with each other (for example, CaS:Eu and SrGa ₂ S ₄ :Eu), the phosphor and the film-forming constituent component can be disposed in different layers. As a result, such undesired reactions can be suppressed, and the life of the phosphor sheet can be prolonged. In this case, it is preferred to use an oxide phosphor (preferably (BaSr) ₃ SiO ₅ :Eu) having a red fluorescent peak having a wavelength of 590 to 620 nm by irradiation with blue excitation light. The red-emitting phosphor sheet forming composition is used to form one of the phosphor layers 1a and 1b, and the vulcanized fluorescent layer having a green fluorescent peak having a wavelength of 530 to 550 nm by irradiation with blue excitation light is used. The phosphor sheet forming composition of the body (preferably SrGa ₂ S ₄ :Eu) forms the other.

If the thickness of the phosphor layers 1, 1a, 1b is too thin, the absolute amount of the phosphors is correspondingly reduced, so that sufficient luminous intensity cannot be obtained. On the other hand, if the thickness is too thick, the target chromaticity cannot be obtained, so Preferably, it is 20 to 150 μm, more preferably 60 to 120 μm.

As the transparent base materials 2a and 2b or the transparent separator 3, a thermoplastic resin film having a thickness of 10 to 100 μm, or a heat or photocurable resin film can be used. E.g, Examples thereof include a polyester film, a polyamide film, a polyimide film, a polyfluorene film, a triacetyl cellulose film, a polyolefin film, and the like. In order to improve the adhesion to the composition for forming a phosphor sheet, the surface of the film may be subjected to corona discharge treatment, decane coupling agent treatment or the like as needed.

In the present invention, as shown in FIGS. 3 and 4, the phosphor sheets 10 of FIGS. 1 and 2 are further sealed from both surfaces by the two sealing films 30a and 30b. Thereby, penetration of moisture into the phosphor layers 1, 1a, 1b can be further prevented. In this case, it is preferable to also seal the side surface of the phosphor sheet 10 so as not to be exposed.

As such a sealing film 30a and 30b, as shown in FIG. 5, the adhesive layer 30a and 30b can be used for the formation of the adhesive layer 32 on the base film 31. Further, in order to improve the water vapor barrier properties of the sealing films 30a and 30b, the cerium oxide layer 33 having a thickness of 5 to 20 nm may be formed by a vapor deposition method equal to the surface of the base film 31 on the side of the bonding layer 32 or the surface on the opposite side. In the latter case, the surface protective film 34 may be laminated on the yttrium oxide layer 33 via an adhesive layer (not shown).

The base film 31 or the surface protective film 34 can be appropriately selected from the films exemplified in the transparent substrate 2a, 2b or the transparent spacer 3 which have been described.

The adhesive layer in the case where the adhesive layer 32 and the surface protective film 34 are laminated can be appropriately selected from known binders such as an urethane-based adhesive or an acrylic adhesive. The thickness of layer 32 is typically 10 to 50 μm.

The single-layer type phosphor sheet 10 of the present invention as shown in Fig. 1 can be produced by forming a phosphor layer by forming a film for forming a phosphor sheet on a transparent substrate 2 by a conventional method. 1. Another transparent substrate 2 is laminated thereon. Further, the sealing film 30a is provided in such a manner that the adhesive layer 32 is inside. The 30b is sandwiched between both sides of the phosphor sheet 10, and the whole is subjected to thermocompression bonding, whereby the phosphor sheet 10 of the structure shown in Fig. 3 can be manufactured.

Further, it is necessary to irradiate the photocurable compound contained in the phosphor layer 1 with an active energy ray such as ultraviolet rays to photoharden (polymerize), and in this case, the phosphor layer 1 may be directly irradiated with active energy rays, or The active energy ray may be irradiated through the transparent substrate 2 or via the sealing film 30a or 30b.

The two-layer type phosphor sheet 10 of the present invention shown in Fig. 2 can be produced by forming a phosphor layer by forming a film for forming a phosphor sheet on a transparent substrate 2a by a conventional method. 1a, a transparent spacer 3 is laminated thereon, and another phosphor-forming composition for forming a phosphor different from the previous composition for forming a phosphor sheet is formed into a film by a conventional method. The photo body layer 1b has a transparent substrate 2b laminated thereon. Further, the both sides of the phosphor sheet 10 are sandwiched by the sealing films 30a and 30b so that the adhesive layer 30a is formed inside, and the whole is subjected to thermocompression bonding, whereby the phosphor sheet having the structure shown in Fig. 4 can be manufactured. 10.

In addition, it is necessary to irradiate (polymerize) the photopolymerizable compound contained in the phosphor layers 1a and 1b with an active energy ray such as ultraviolet rays, and in this case, the phosphor layers 1a and 1b can be directly irradiated with an activity. The energy ray may be irradiated with the active energy ray via the transparent substrates 2a, 2b, the transparent spacer 3, and/or the sealing films 30a, 30b.

The above-described phosphor sheet of the present invention can be preferably used as the phosphor sheet having a phosphor sheet and a light-emitting device that emits an excitation light source for the excitation light to be irradiated thereto. Other constituent elements constituting such an optical device (for example, light The diffusion member can be configured in the same manner as the known optical device (see Fig. 6 of JP-A-2010-225373). The light emitting device can be used as a self-illuminating device. Moreover, it can also be used as a backlight device of a liquid crystal display element.

Example

Hereinafter, the present invention will be specifically described by way of examples.

Example 1 (manufacture of single-layer type phosphor sheet) (Preparation of a composition for forming a red-green mixed color phosphor sheet)

0.5 parts by mass of a photopolymerization initiator (manufactured by BASF Corporation, Darocure 1173), SrGa ₂ S ₄ :Eu (vulcanized green phosphor) having an average particle diameter of 6 μm, and (BaSr) ₃ SiO ₅ :Eu (oxide) 1.5 parts by mass of each of the red phosphors were uniformly dispersed in 100 parts by mass of photocuring type urethane methacrylate (ARONIX 1600M, Toagosei Co., Ltd.), thereby preparing a composition for forming a phosphor sheet. Things.

(Production of the phosphor sheet of the structure of Fig. 1)

The composition for forming a phosphor sheet was applied to a polyethylene terephthalate film (T11, Toray Co., Ltd.) having a thickness of 25 μm so as to have a dry thickness of 115 μm, and then irradiated with ultraviolet rays (7000 mJ/ The urethane methacrylate is polymerized by cm ² ), thereby forming a phosphor layer. A polyethylene terephthalate film (A4300, Toyobo Co., Ltd.) having a thickness of 38 μm was laminated on the phosphor layer, and subjected to thermocompression bonding treatment (100 ° C, 0.2 MPa), whereby the structure of FIG. 1 was obtained. Fluorescent film.

(production of sealing film)

A polyolefin-based adhesive layer (Septon V9827, Kuraray Co., Ltd.) having a thickness of 20 to 25 μm was formed on one surface of a polyethylene terephthalate film (T-11, Toray Co., Ltd.) having a thickness of 25 μm. A surface protective film of an urethane-based adhesive layer was formed by interposing an urethane-based adhesive layer on the other surface of the polyethylene terephthalate film to form a sealing film. The surface protective film is formed on the yttrium oxide vapor-deposited layer of a polyethylene terephthalate film (TECH BARRIER, Mitsubishi Resin Co., Ltd.) having a thickness of 12 μm which is formed by a ruthenium oxide evaporation layer having a thickness of approximately 20 nm. The urethane of 1 to 2 μm is produced by laminating the layer. The resulting sealing film had a moisture permeability of 0.3 g/m ² . 24 hr. Atm.

(Production of the phosphor sheet of the structure of Fig. 3)

A sealing film was placed on both surfaces of the phosphor sheet of the structure of Fig. 1, and subjected to a thermocompression bonding treatment (100 ° C, 0.2 MPa), whereby a phosphor film sealed with a sealing film was obtained.

Example 2 (Manufacture of double-layer type phosphor sheet) (Preparation of a composition for forming a green phosphor sheet)

0.5 parts by mass of a photopolymerization initiator (manufactured by BASF Corporation, Darocure 1173) and 1.5 parts by mass of SrGa ₂ S ₄ :Eu (sulfurized green phosphor) having an average particle diameter of 6 μm were uniformly dispersed to a photocurable amine A composition for forming a green phosphor sheet was prepared by using 100 parts by mass of ethyl formate methacrylate (ARONIX 1600M, East Asia Synthetic Co., Ltd.).

(Preparation of a composition for forming a red phosphor sheet)

0.5 parts by mass of a photopolymerization initiator (manufactured by BASF Corporation, Darocure 1173) and 3 parts by mass of (BaSr) ₃ SiO ₅ :Eu (oxide red phosphor) having an average particle diameter of 10 μm were uniformly dispersed to a photocuring type. A composition for forming a red phosphor sheet was prepared by using 100 parts by mass of urethane methacrylate (ARONIX 1600M, Toagosei Co., Ltd.).

(Production of the phosphor sheet of the structure of Fig. 2)

The green phosphor sheet forming composition was applied to a polyethylene terephthalate film (T11, Toray Co., Ltd.) having a thickness of 25 μm so as to have a dry thickness of 115 μm, and then irradiated with ultraviolet rays (7000 mJ). /cm ² ) The urethane methacrylate is polymerized to form a green phosphor layer.

A transparent spacer (polyethylene terephthalate film (A4300, Toyobo Co., Ltd.)) having a thickness of 38 μm was deposited thereon, and red fluorescent light was applied on the transparent spacer to a dry thickness of 20 μm. The composition for forming a body sheet was then irradiated with ultraviolet rays (7000 mJ/cm ² ) to polymerize urethane methacrylate, thereby forming a red phosphor layer. Further, a phosphor sheet having the structure of Fig. 2 was obtained by laminating a polyethylene terephthalate film (T11, Toray Co., Ltd.) having a thickness of 25 μm.

(Production of the phosphor sheet of the structure of Fig. 4)

The same sealing film as that of the user of Example 1 was placed on both surfaces of the phosphor sheet of the structure of Fig. 2, and subjected to thermocompression bonding treatment (100 ° C, 0.2 MPa), thereby obtaining a sealing film-sealed phosphor sheet. .

Example 3 (Production of green monochromatic single-layer phosphor sheet)

A composition for a phosphor sheet was prepared in the same manner as in Example 1 except that (BaSr) ₃ SiO ₅ :Eu (oxide red phosphor) was used, and the structure of FIG. 1 and further FIG. 3 was obtained. Fluorescent film. The phosphor sheet is green and monochromatic.

Comparative example 1

A butyl methacrylate-glycidyl methacrylate (BMA-GMA) copolymer (DF-242, Fujikura Kasei Co., Ltd.) was used instead of the urethane methacrylate, and the same as Example 1 A composition for forming a phosphor sheet was prepared in the same manner, and a phosphor sheet having the structure shown in Fig. 1 and Fig. 3 was produced.

Comparative example 2

Firefly was prepared in the same manner as in Example 1 except that methyl methacrylate-butyl acrylate (MMA-BA) copolymer (NABSTAR N800AS, Kaneka Co., Ltd.) was used instead of urethane ethyl methacrylate. A phosphor sheet having the structure shown in Fig. 1 and Fig. 3 was produced as a composition for forming a thin film.

Comparative example 3

A hydrogenated styrene-ethylene-butylene-styrene block (hydrogenated SEBS) copolymer (Septon V9827, Kuraray Co., Ltd.) was used instead of urethane methacrylate, and no ultraviolet rays were irradiated, in addition to A composition for forming a phosphor sheet was prepared in the same manner as in Example 1, and a phosphor sheet having the structure of Fig. 1 and Fig. 3 was produced.

Comparative example 4

Using 40 parts by weight of hydrogenated styrene-ethylene-butylene-styrene block (hydrogenated SEBS) copolymer (Septon V9827, Kuraray Co., Ltd.) and 0.5 parts by weight of maleic anhydride, instead of ethyl urethane A composition for forming a phosphor sheet was prepared in the same manner as in Example 1 except that the methacrylate was not irradiated with ultraviolet rays, and a phosphor sheet having the structure of Fig. 1 and Fig. 3 was produced.

Comparative Example 5

A hydrogenated styrene-ethylene-butylene-styrene block (hydrogenated SEBS) copolymer (Septon V9827, Kuraray Co., Ltd.) was used instead of urethane methacrylate, and no ultraviolet rays were irradiated, in addition to A composition for forming a phosphor sheet was prepared in the same manner as in Example 3, and a phosphor sheet having the structure of Fig. 1 and Fig. 3 was produced. The phosphor sheet is green and monochromatic.

Comparative Example 6

A butyl methacrylate-glycidyl methacrylate (BMA-GMA) copolymer (DF-242, Fujikura Kasei Co., Ltd.) was used instead of urethane methacrylate, and ultraviolet rays were not irradiated. A composition for forming a phosphor sheet was prepared in the same manner as in Example 3, and a phosphor sheet having the structure of Fig. 1 and Fig. 3 was produced. The phosphor sheet is green and monochromatic.

(Evaluation)

With respect to the sealed phosphor sheets of the respective examples and the comparative examples, the chromaticity difference and the luminescence spectrum intensity ratio were measured and evaluated by the following methods. The results obtained are shown in Tables 1 and 2.

<chromaticity difference (chromaticity shift)>

The resulting sealed phosphor sheet was allowed to stand in an environment of 60 ° C and 90% Rh for 500 hours. The chromaticity difference (JIS Z8518) Δu'v' before and after the placement was determined and evaluated according to the following criteria.

Level benchmark

A: △u'v'<0.005

B: 0.005 ≦ Δu'v' <0.010

C:0.010≦△u'v'

<Light emission intensity ratio>

The obtained sealed phosphor sheet was allowed to stand in an environment of 85 ° C and 85% Rh for 48 hours, and the intensity of the luminescence spectrum before and after standing was measured using a spectroradiometer (TOPCON SR-3, TOPCON Co., Ltd.) ( SR) The ratio of the luminescence spectrum intensity (SR) after standing to the luminescence spectrum intensity (SR) before standing was determined, and evaluated based on the following criteria. In practical use, the SR ratio is expected to be 0.7 or more (A evaluation).

Level benchmark

A: 0.7≦SR ratio

B: 0.5≦SR ratio <0.7

C: SR ratio <0.5

As can be seen from Table 1, in the case of the phosphor sheet of Example 1, the chromaticity difference was evaluated as A. On the other hand, in the case of the phosphor sheets of Comparative Examples 1 to 4, a maleic anhydride was added to the BMA-GMA copolymer, the MMA-BA copolymer, the hydrogenated SEBS, or the hydrogenated SEBS instead of the amine formate B. The ester methacrylate was used as a main component of the film-forming composition, and as a result, the chromaticity difference was evaluated as B or C. Further, since the phosphor sheet of the second embodiment is such that the green phosphor and the red phosphor used in the first embodiment are disposed on the respective phosphor layers, the chromaticity difference affected by the combination of the phosphors is as follows. Expected to be an A rating.

Then, as is clear from Table 2, the phosphor sheets of Example 3 and Comparative Examples 5 and 6 are those which emit green monochromatic light, and therefore are suitable as an example for measuring the intensity ratio of the luminescence spectrum. Actually, in the case of the phosphor sheet of Example 3, the luminescence spectral intensity ratio was evaluated as A, whereas in the case of the phosphor sheets of Comparative Examples 5 and 6, the luminescence spectral intensity ratio was B evaluation or C evaluation.

[Industrial availability]

In the composition for forming a phosphor sheet of the present invention, the film-forming composition is used in a variety of resins or polymerizable compounds, and is excellent in light resistance and light absorption to visible light as compared with a thermoplastic resin or the like. A resin, and a photocurable compound which can be obtained at a relatively low cost. Thus, the composition for forming a phosphor sheet of the present invention is excellent in light resistance, low in light absorbability to visible light, and deterioration of phosphor due to moisture, and low-cost phosphor sheet It is useful to manufacture raw materials.

1, 1a, 1b‧‧‧ phosphor layer

2, 2a, 2b‧‧‧ transparent substrate

3‧‧‧Transparent spacers

10‧‧‧Fluorescent film

20‧‧‧Laminated phosphor layer

30a, 30b‧‧‧ sealing film

31‧‧‧ base film

32‧‧‧Next layer

33‧‧‧Oxide layer

34‧‧‧Surface protection film

Figure 1 is a cross-sectional view of a single layer type phosphor sheet.

Figure 2 is a cross-sectional view of a two-layered phosphor sheet.

Figure 3 is a cross-sectional view of a preferred single layer type phosphor sheet.

Figure 4 is a cross-sectional view of a preferred two-layer type phosphor sheet.

Figure 5 is a cross-sectional view of the sealing film.

1‧‧‧Fluorescent layer

2‧‧‧Transparent substrate

10‧‧‧Fluorescent film

Claims (16)

A composition for forming a phosphor sheet, comprising a film-forming composition and a powdered phosphor that emits fluorescence by irradiation of excitation light, and the film-forming composition contains a photocurable compound. The composition for forming a phosphor sheet according to the first aspect of the invention, wherein the photocurable compound contains a photocurable (meth) acrylate. The composition for forming a phosphor sheet according to the second aspect of the invention, wherein the photocurable (meth) acrylate contains urethane (meth) acrylate. The composition for forming a phosphor sheet according to claim 3, wherein the urethane (meth) acrylate is a reactant ester of a polyol and isophorone diisocyanate using 2-hydroxypropyl acrylate. The winner. The composition for forming a phosphor sheet according to claim 3, wherein the photocurable (meth) acrylate contains at least 10 parts by mass of ethyl urethane (meth) acrylate in 100 parts by mass of the photocurable (meth) acrylate. ester. The phosphor sheet forming composition according to any one of claims 1 to 5, wherein the phosphor contains at least a red fluorescent peak having a wavelength of 590 to 620 nm by irradiation with blue excitation light. Oxide phosphor. The composition for forming a phosphor sheet according to the sixth aspect of the invention, wherein the oxide phosphor is (BaSr) ₃ SiO ₅ :Eu. The phosphor sheet forming composition according to any one of claims 1 to 5, wherein the phosphor contains at least a green fluorescent peak having a wavelength of 530 to 550 nm by irradiation with blue excitation light. Sulfurized phosphor. The composition for forming a phosphor sheet according to the eighth aspect of the invention, wherein the vulcanized phosphor is SrGa ₂ S ₄ :Eu. The composition for forming a phosphor sheet according to any one of claims 1 to 5, wherein the phosphor has a red fluorescent peak having a wavelength of 590 to 620 nm by irradiation with blue excitation light. An oxide phosphor and a mixed phosphor of a sulfide-based phosphor having a green fluorescent peak having a wavelength of 530 to 550 nm by irradiation with blue excitation light. The composition for forming a phosphor sheet according to claim 10, wherein the oxide phosphor having a red fluorescent peak is (BaSr) ₃ SiO ₅ :Eu, and the sulfurized fluorescent light having a green fluorescent peak is obtained. The body is SrGa ₂ S ₄ :Eu. A phosphor sheet for holding a phosphor layer that emits fluorescence by irradiation of excitation light between a pair of transparent substrates, and the phosphor layer is for forming a phosphor sheet of the first application of the patent scope A film is obtained by using a composition. The phosphor sheet of claim 12, wherein the phosphor layer is obtained by forming a single layer of a composition for forming a phosphor sheet according to claim 10 or 11. The phosphor sheet of claim 11, wherein the phosphor layer has a red phosphor layer on one of the transparent spacers and a green phosphor layer on the other of the transparent spacers. The phosphor layer is obtained by forming a film for forming a phosphor sheet according to claim 6 or 7 in a single layer, and the green phosphor layer is a phosphor of the eighth or ninth aspect of the patent application. The sheet forming composition was obtained by film formation in a single layer. A phosphor sheet according to any one of claims 12 to 14, further comprising two sealing films having an adhesive layer on one side from both sides seal. A light-emitting device comprising the phosphor sheet of any one of claims 12 to 15 and an excitation light source that emits excitation light for irradiating the phosphor sheet.