JPH11323324A - Fluorescent resin sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent resin sheet wherein concentration extinction of a fluorescent substance is inhibited and a rare earth complex having an extremely high ultraviolet sensitizing effect is dispersed in a resin matrix with a good compatibility. SOLUTION: A fluorescent resin sheet is prepared by dispersing a rare earth complex containing a ligand having a hyperbranched structure as a structural component in a resin matrix. Here, the hyperbranched structure has an aromatic ring. Also, the hyperbranched structure has an aromatic ring at the focal point in the structure. Furthermore, in the ligand having the hyperbranched structure, a coordinated functional group is directly linked to the focal point in the hyperbranched structure. Also, the ligand having the hyperbranched structure has a carboxyl group as the coordinated ligand.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent resin sheet. The sheet exhibits a high-luminance planar light-emitting function due to the excellent ultraviolet light sensitizing effect of the rare earth complex containing a ligand having a dispersed hyperbranched structure as a component, and has an excellent balance of mechanical properties. Further, since it can be easily produced by a known melt molding method, solution casting method, or the like, it is used in the form of, for example, a light guide plate of a display, a wavelength conversion plate, an agricultural film, an ultraviolet light cut film, and the like.

[0002]

2. Description of the Related Art Some rare earth cations emit fluorescence in a wide wavelength range from ultraviolet to infrared. Since these are based on transitions of f-orbital electrons that are hardly affected by the external field such as a ligand field, the wavelength width of the emission band is much narrower than that of an organic phosphor or the like, and useful fluorescent light having extremely high color purity in principle. Is a seed. Further, it has been applied to a display of a television receiver or the like, because it is superior to an organic phosphor in stability against heat and light.

For example, terbium and europium trivalent cations (Tb ³⁺ and Eu ³⁺ , respectively) generate green and red fluorescence with extremely high color purity by ultraviolet light excitation, respectively, and europium divalent cation ( Eu ²⁺ ) emits blue fluorescent light, so that it is possible to arrange the three primary colors of light, and it has recently been attracting attention as a high-quality display fluorescent species (see Japanese Patent Application Laid-Open No. 9-272864). .

Heretofore, it has been practiced to add a rare earth cation to an inorganic glass matrix to obtain a sheet-like molded body having a fluorescent ability. For example, Sawato et al., Industrial Materials, Vol. 45, No. 7, page 107 (1997) describes practical examples of transparent blue fluorescent glass. However, in order to use an inorganic glass matrix as a display requiring portability such as a notebook computer or a mobile phone, there are problems in lightness, workability, impact resistance, and the like.

On the other hand, the use of these rare earth cations in organic matrices, especially in transparent resin matrices, is also being carried out. For example, a resin composition such as an acrylic resin or an aromatic polycarbonate resin to which a phosphor is added, and a sheet-like molded product thereof are known. Further, for example, Okamoto,
Y. , Et al. Macromolecules,
Vol. 14, p. 17 (1981), reports that an aromatic polymer such as a polystyrene skeleton exhibits an ultraviolet photosensitization effect as a ligand. This is because the rare-earth cation itself does not receive the excitation light and emits light, but the energy of the excitation light absorbed by the ligand is transmitted to the cation to emit a strong light (light).
harvesting).

[0006]

However, these conventional methods for adding rare earth cations have room for at least two improvements. That is, even if apparent transparency is obtained, dispersibility at the molecular level of the phosphor is not guaranteed, and concentration quenching at the time of high concentration addition due to aggregation is likely to occur, and positive control by controlling the ligand structure The important point is that the sensitizing effect is not always optimized.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resin sheet in which a rare-earth cation to be added efficiently emits light. Quenching is suppressed in principle, and a rare earth complex having an extremely high ultraviolet sensitizing effect is dispersed in the resin matrix with good compatibility,
An object of the present invention is to provide a resin sheet that emits high-luminance fluorescent light.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to achieve the above object, and have systematically studied a rare-earth cation complex. The effect of the rare earth complex as a constituent component making it difficult for the cations at the center of the complex to aggregate with each other due to the space exclusion effect (effect of occupying space) (concentration quenching suppression effect)
I found

Further, rare earths having an extremely high ultraviolet light sensitizing effect, which have never existed heretofore, can be obtained by controlling the structure of the ligand, such as the presence of an aromatic ring absorbing ultraviolet light in the ligand having a hyperbranched structure. The present invention has been found to be a complex and at the same time exhibit extremely good compatibility with general-purpose resins, thus completing the present invention. That is, the gist of the present invention resides in a fluorescent resin sheet characterized in that a rare earth complex containing a ligand having a hyperbranched structure as a component is dispersed in a resin matrix.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. (Rare earth complex) The rare earth complex used in the present invention contains a rare earth cation and a ligand having a hyperbranched structure as essential components. Specific examples of such rare earth cations include:
La ²⁺ , La ³⁺ , Ce ²⁺ , Ce ³⁺ , Ce ⁴⁺ , Pr ²⁺ , P
r ³⁺ , Pr ⁴⁺ , Nd ²⁺ , Nd ³⁺ , Nd ⁴⁺ , Pm ²⁺ , Pm
³⁺ , Sm ²⁺ , Sm ³⁺ , Eu ²⁺ , Eu ³⁺ , Gd ²⁺ , G
d ³⁺ , Tb ²⁺ , Tb ³⁺ , Tb ⁴⁺ , Dy ²⁺ , Dy ³⁺ , Dy
⁴⁺ , Ho ²⁺ , Ho ³⁺ , Er ²⁺ , Er ³⁺ , Tm ²⁺ , T
Lanthanoid cations such as m ³⁺ , Yb ²⁺ , Yb ³⁺ , Lu ²⁺ and Lu ³⁺ , and cations of Group 3A elements of the periodic table such as scandium and yttrium.

Of these, Pr ³⁺ , Nd ³⁺ , Sm ³⁺ ,
Eu ³⁺ , Tb ³⁺ , Dy ³⁺ , Ho ³⁺ , Er ³⁺ , Tm ³⁺ , Y
Trivalent lanthanoid cations such as b ³⁺ are particularly useful in the present invention in that they emit fluorescence having characteristics such as a visible to near-infrared region, a long lifetime, and a narrow wavelength width. Among them, Eu ^{3+ and Tb 3+}
Is most useful because it has strong fluorescence in the visible light range.
The preferable content of the rare earth cation in the resin sheet of the present invention varies depending on the conditions around the cation such as a ligand. However, when the content is less than 0.001% by weight, a sufficient light emitting effect cannot be obtained. Conversely, if the content exceeds 10% by weight, the resin sheet tends to be turbid and mechanical properties such as toughness tend to decrease. Thus, this amount is 0.001 to 10% by weight, preferably 0.005 to 8% by weight, more preferably 0.01 to 6% by weight, most preferably 0.03 to 4% by weight. The weight% value can be calculated by ash analysis of a given resin sheet sample.

(Hyperbranched Structure) The ligand of the rare earth complex used in the present invention has a hyperbranched structure. The term hyperbranched here refers to dendritic branching, in other words, Hawker, C. et al.
J. et al; Chem. Soc. Chem.
Commun. , 1990, p. 1010, Tomal
ia, D.I. A. et al; Angew. Chem. I
nt. Ed. Engl. 29, 138 (199
0), Hawker, C .; J. et al; Am.
Chem. Soc. 112, 7638 (199
0), Frechet, J. et al. M. J. ; Sciencec
e, 263, 1710 (1994) or Masaaki Kakimoto; a concept typified by a dendrimer structure described in detail in literatures such as Chemistry, 50, 608 (1995). No restrictions. Further, the hyperbranched structure referred to here is one focal point (Foca).
l point, focus).

In the present invention, the focal point is
It means the starting point of the dendritic branch, that is, the last branch point when the molecular chain is moved backward from the end of an arbitrary branch of the dendritic structure in the branch convergence direction. In the hyperbranched structure of the present invention, the number of branch points is not limited, and in an extreme case, the first generation (1st generator) may be used in the above-mentioned various documents relating to dendrimers.
A structure including only the focal point referred to as n) as a branch point is also included.

The ligand of the rare earth complex used in the present invention may have any position in the hyperbranched structure (for example, in a focal point terminal, a branch terminal, or a hyperbranched structure) even if it is composed of only a hyperbranched structure. May contain any chemical structure. Such an arbitrary chemical structure includes, for example, an alkyl group, an alkenyl group, an alkynyl group, an alkylene chain,
Aliphatic structures such as alkoxy groups, polyether chains such as polyethylene glycol and polypropylene glycol, siloxane chains such as polydimethylsiloxane, aromatic rings such as phenyl, naphthyl, pyridyl, and phenylene groups, halogen atoms, phosphorus atoms, and hydroxyl groups , An amino group, a mercapto group, a carboxyl group, an ester group, an amide group, and an onium cation such as ammonium and phosphonium. Among the ligands in the rare earth complex used in the present invention,
It is desirable to include at least one ligand having a hyperbranched structure, but any ligand may be used in combination as long as the non-aggregation property of the complex in the resin matrix is not impaired.

(Degree of Branching of Hyperbranched Structure) The above hyperbranched structure desirably has as high a degree of branching as possible. This is presumably because, when considering molecules having the same molecular weight in the same monomer (repeating unit) structure, the more the number of branch points, the easier it is to adopt a conformation with a high space exclusion effect. In other words, as it approaches a linear molecular structure without branching, it becomes possible to change from a conformation that is aggregated in a filiform shape with a high space exclusion effect to a low conformation with the same effect that the molecular chain is extended, As a result, the probability of taking a state where the space exclusion effect is low increases.

As means for quantifying the degree of branching, for example, measurement of the relationship between the intrinsic viscosity and the absolute molecular weight in a dilute solution, or assignment to each of a branched unit structure and a non-branched unit structure in a nuclear magnetic resonance (NMR) spectrum. And the like utilizing the integrated value of the signal. In the present invention, preferable conditions for the degree of branching when the molecular weight of the ligand exceeds about 2000 include, for example, a weight average molecular weight Mw measured by a mass spectrum method or a light scattering method and a weight average molecular weight Mw measured by a GPC method. (GPC) and Mw / Mw (G
PC)> 1.

An example in which Mw is larger than Mw (GPC) is as follows.
Hawker, C .; J. et al. J .; Am. Ch
em. Soc. 112, 7638 (1990) and Uhrich, K. et al. E. FIG. et al; Macromol
ecules, vol. 25, p. 4583 (1992), which shows that even when the absolute molecular weight (ie, Mw) as measured by mass spectrometry or light scattering is the same, as the degree of branching increases, It is qualitatively interpreted that the spatial extent (ie, Mw (GPC)) of the polymer chains observed in a good solvent becomes smaller. There is no limitation on the method of the above mass spectrum as long as a molecular peak is given, and for example, a Matrix assisted laser de- ter that is preferably used for a relatively high molecular weight molecule having a molecular weight of about 1000 or more or an unstable molecule.
sorption ionization (MALD
I) It may be preferable to apply a new method such as a mass spectrum or an Electrospray mass spectrum.
Also, all GPC measurements in the description of the present invention need to be performed in a good solvent for the ligand. Mw / Mw (GPC)
Is usually at most about 3 in the range of the molecular weight, but is not particularly limited.

(Molecular Weight and Molecular Weight Distribution of Ligand) The molecular weight of the hyperbranched structure is arbitrary, but preferably has a molecular weight of 300 to 50,000 in view of a space exclusion effect of shielding rare earth cations. If the range of the molecular weight is too small, the space exclusion effect may decrease. On the contrary, if the range is too large, the complex may become too large and the amount of the cation to be added may be restricted. Therefore, the molecular weight range is preferably 300
~ 40000, more preferably 400 ~ 30000, even more preferably 450 ~ 20,000, most preferably 50
0 to 10,000.

The molecular weight distribution of the ligand having such a hyperbranched structure is such that the number average molecular weight Mn (GPC) and the weight average molecular weight Mw (GPC) measured by gel permeation chromatography (GPC) are 1: 1. 0 ≦ Mw (GPC) / M
It is desirable to satisfy the relationship of n (GPC) ≦ 15. If the value of Mw (GPC) / Mn (GPC) is too large, the spatial spread of the rare-earth complex becomes too large, and the spatial exclusion effect may be impaired. Therefore, Mw (GPC)
It can be said that the smaller the value of / Mn (GPC) is, the more desirable it is.
It is as follows. When the dendrimer is used as a hyperbranched polymer, the molecular weight distribution can be theoretically changed to Mw (GPC) / M
This is very preferable because the value of n (GPC) can be set to 1.0.

(Chemical Structure of Hyperbranched Structure) The primary role of the hyperbranched structure in the ligand of the rare-earth complex used in the present invention is the above-described space exclusion effect, and therefore occupies a certain space and causes the resin matrix to occupy a certain space. There is no limitation on the chemical structure of the hyperbranched structure as long as it has compatibility with the hyperbranched structure. However, when the hyperbranched structure has an aromatic ring, the rare-earth complex exerts extremely strong fluorescent ability, and the resin sheet of the present invention and a member using the same may emit light effectively. This is because the aromatic ring has a strong absorption band mainly in the ultraviolet region. That is, a mechanism (sensitizing effect) is assumed in which the energy of light absorbed by the hyperbranched structure having an aromatic ring is transported to the rare earth cation, and the cation is effectively excited to generate fluorescence.

Such a sensitizing effect has been conventionally known (for example, Tanner, SP et al; J. Am.
Chem. Soc. 96, 706 (1974),
Okamoto, Y .; et al; Macromole
cures, 14, 17 (1981), Sabba
tini, N .; et al; Coordination
Chemistry Rev. In the present invention, particularly when the hyperbranched structure has an aromatic ring, very strong sensitization of the hyperbranched structure to rare earth cations such as Tb ³⁺ in the present invention. The effect is retained in a general-purpose resin matrix, and an extremely excellent effect of exhibiting excellent compatibility is exhibited.

Preferred aromatic ring structures from the viewpoint of the sensitizing effect include hydrocarbon aromatic rings such as benzene ring, naphthalene ring, anthracene ring and pyrene ring, oxygen-containing aromatic rings such as furan ring, pyridine ring and quinoline. Examples include a nitrogen-containing aromatic ring such as a ring and a pyrrole ring, and a sulfur-containing aromatic ring such as a thiophene ring. Among them, hydrocarbon aromatic rings such as a benzene ring, a naphthalene ring and an anthracene ring are particularly effective.

Specific examples of the preferred hyperbranched structure in terms of the sensitizing effect include poly (benzyl ether), poly (phenylene ether), and poly (naphthylene ether).
Aromatic polyether structures such as poly (hydroxybenzoic acid), aromatic polyester structures such as poly (hydroxynaphthalenecarboxylic acid), aromatic polyamide structures such as poly (aminobenzoic acid) and poly (aminonaphthalenecarboxylic acid); Polyarylene sulfide structures such as polyphenylene sulfide and polynaphthylene sulfide, conjugated aromatic polymer structures such as polyphenylene, polyphenylacetylene, and polyphenylene vinylene, aromatic polycarbonate, aromatic polyester carbonate, aromatic polyimide, aromatic polyamideimide, and aromatic Group polyurethane, aromatic polyurethane urea, aromatic polyurea and the like. Among them, a poly (benzyl ether) structure is excellent in terms of ease of synthesis and particularly large fluorescent ability when combined with a Tb ³⁺ cation.

Of these exemplified structures, a plurality of kinds may coexist in one hyperbranched structure, and the rare earth complex used in the present invention may have a plurality of ligands having a hyperbranched structure. Seeds may be included. Further, the resin sheet of the present invention may contain a plurality of rare earth complexes. The ligand having a hyperbranched structure constituting the rare earth complex used in the present invention preferably has an aromatic ring at the focal point of the hyperbranched structure from the viewpoint of a sensitizing effect. It is presumed that this is to help the light energy absorbed by the ligand to move smoothly to the rare earth cation.

(Coordination Functional Group) The ligand of the rare earth complex used in the present invention has a coordination functional group to a rare earth cation. Here, the coordination functional group is a functional group having an interaction with a rare earth cation in the complex by Coulomb force or coordination bond. Such coordination functional groups include a carboxyl group,
acidic groups such as β-diketone group, sulfonic acid group, phosphoric acid group, phosphorous acid group, hypophosphorous acid group, thioic acid group (-COSH), dithioic acid group (-CSSH), xanthogenic acid group and nitric acid group Hydroxyl groups such as alcoholic hydroxyl groups and phenolic hydroxyl groups, carbonyl groups such as ketone groups and ester groups, primary amino groups, secondary amino groups, tertiary amino groups, nitro groups, nitrile groups (cyano groups), isonitrile groups, etc. A nitrogen-containing functional group, a nitrogen-containing or sulfur-containing aromatic ring such as a pyrrole ring, a pyridine ring, a thiophene ring, or a thiazole ring; a sulfur such as a mercapto group (thiol group), a disulfide group, a sulfide group, an isothiocyanate group, or a thiocarbamate group. Containing functional group,
Trivalent phosphorus atom functional group such as phosphine group, selenol group,
Examples include selenium-containing functional groups such as diselenide groups and selenide groups. Among them, preferred from the viewpoint of complex formation ability are acid groups such as carboxyl group, β-diketone group, sulfonic acid group, phosphoric acid group, xanthic acid group, primary amino group, secondary amino group, and tertiary amino group. And a nitrogen-containing functional group such as a nitrile group, a sulfur-containing functional group such as a mercapto group, a disulfide group, a sulfide group and a thiocarbamate group, and a phenolic hydroxyl group.

Among them, acidic groups such as carboxyl groups and β-diketone groups, carboxylate groups, tertiary amino groups, mercapto groups, disulfide groups, sulfide groups, sulfur-containing functional groups such as thiocarbamate groups, and phenolic hydroxyl groups are more preferred. More preferably, acidic groups such as carboxyl group and β-diketone group, and sulfur-containing functional groups such as mercapto group are more preferable, and carboxyl group is most preferable.

The coordinating functional groups exemplified above may be present in any number and in any combination in one ligand, and a series of such functional groups form the coordination site of the rare earth cation. Often they are arranged with the intent to occupy efficiently and exhibit excellent complex stability. However, from the viewpoint of the coordination efficiency to the rare earth cation, the number of the functional groups present in one ligand is 1
It is suitably from 30 to 30, preferably from 1 to 20, more preferably from 1 to 15, and most preferably from 1 to 10. The adjacent functional groups are desirably separated by 0 to 10 series-bonded atoms, and the number of the series-bonded atoms is more preferably 0 to 7, more preferably 0 to 7.
5, most preferably 0-3.

Examples of the structure of the series of functional groups exhibiting such excellent complex stability include ethylenediaminetetraacetic acid (commonly known as EDTA) and diethylenetriaminepentaacetic acid (commonly known as DT).
PA) or 1,4,7,10-tri (acetic acid) tetraazacyclododecane (commonly known as DOT)
Polyaminocarboxylic acids such as A) and polynitrogen-containing aromatic rings represented by porphyrins such as porphyrin ring, protoporphyrin ring, ethioporphyrin ring and mesoporphyrin ring.

In the ligand, it is preferable that the coordinating functional group and the focal point of the hyperbranched structure are bonded via 0 to 10 tandem atoms. This is because the focal point, which is the starting point of branching, coordinates at the center of the complex and the dendritic hyperbranch extends outside the complex. This is because the efficiency of the space exclusion effect and the rare earth of the excitation energy due to the sensitizing effect are high. It is presumed that this is because it is preferable in terms of the efficiency of transport to cations. Here, the tandem atom has a straight-chain structure, and its constituent elements are not limited. When the number of the tandem atoms is 10 or more, the space exclusion effect and the sensitizing effect may be reduced. Therefore, this number is preferably 7 or less, more preferably 5 or less, still more preferably 2 or less, and most preferably 2 or less. Preferably, it is 0 (that is, the coordination functional group is directly bonded to the focal point atom of the hyperbranched structure).

(Method for Producing Rare Earth Complex) The rare earth complex used in the present invention comprises a Coulomb force (ionic bond) or a coordination bond between a rare earth cation and a coordination functional group in the ligand. Formation of ionic bonds is possible by an anion exchange reaction. More specifically, a ligand or coordination with a salt of a lanthanoid cation with a carboxylic acid such as formic acid, acetic acid, oxalic acid, or propionic acid, or a salt with a chloride ion, a bromide ion, or an iodide ion; The reaction is carried out by mixing a salt of the salt (eg, sodium salt, potassium salt, etc.).

In the above complex, it is desirable that all counter anions that neutralize the positive charge of the metal cation are ligands having a hyperbranched polymer structure. This is because of the relatively small anions such as fluoride ions, chloride ions, bromide ions, halide ions such as iodide ions, sulfate ions, nitrate ions, formate ions, acetate ions, oxalate ions and the like. This is because residual anions, which are widely used in the art, reduce the space exclusion effect described above. Therefore, when producing such a complex by the above-mentioned anion exchange reaction, it is desired to precisely control the equivalent relation between the lanthanoid cation and the ligand. However, the effect of the present invention may be obtained even if an excess of a ligand is allowed to act on the cation because the product contains a desired complex. A coordinating compound such as tri-n-octylphosphine oxide (TOPO) may be added at the time of preparation of the rare earth complex for the purpose of suppressing a decrease in fluorescence due to hydration to a rare earth cation.

(Resin Matrix) The resin matrix material for dispersing and supporting the rare earth complex in the resin sheet of the present invention is not particularly limited as long as it has the light transmittance required for the intended use, but the mechanical properties of the obtained resin sheet are not limited. Preferred examples from the balance are amorphous organic polymers transparent to light in a desired wavelength range (for example, acrylic resins such as polymethyl methacrylate and polymethyl acrylate, styrene resins such as polystyrene resins, bisphenol A).
Aromatic polycarbonate resin such as polycarbonate, polyvinyl chloride, vinyl chloride resin such as a polymer using vinyl acetate, ethylene, propylene, vinyl ether or the like as a copolymerization monomer of vinyl chloride, and amorphous polyolefin resin). . The resin sheet of the present invention includes glass filler, glass flakes, glass beads, mica, talc, montmorillonite, smectite, synthetic mica, synthetic smectite and other inorganic fillers, and thermoplastics such as polyester and polyamide, as long as the effects are not significantly impaired. Resins, rubber components such as styrene-based thermoplastic elastomers, resin beads, hollow beads, heat stabilizers, antioxidants, ultraviolet absorbers, flame retardants, plasticizers and lubricants such as petrolatum and glycerin esters, metal powders, semiconductor powders, Arbitrary additives such as graphite, resin powder, pigment, dye, fluorescent dye, and compatibilizer may be added. The method of mixing the rare earth complex with the resin matrix is arbitrary, and known methods such as solution mixing and melt mixing can be used.

(Resin Sheet) The method of forming the resin composition thus obtained into a resin sheet is also optional.
Known film forming methods such as a melting method such as T-die extrusion film forming and inflation film forming, and a solution casting method can be used. The thickness of the resin sheet in the present invention is not particularly limited, but is generally 0.01 to 30 mm, preferably 0.05 to 30 mm.
It is a planar molded body having a thickness of about 20 mm, particularly preferably about 0.1 to 10 mm, and the shape of the surface is not particularly limited. Therefore, it means a molded article having a flat or curved surface, such as a film, a film, a sheet, or a plate, which is obtained by the above-described various molding methods.

In order to make the effect of the present invention remarkable, in the resin matrix of the resin sheet of the present invention,
The rare-earth cation particles are preferably in a non-aggregated state in which the center-to-center distance is 7 Å or more. this is,
For example, the center-to-center distance observed with a transmission electron microscope is 7
If the thickness is less than Å, the fluorescence intensity (quenching), which is considered to be caused by the energy transfer between cations, becomes remarkable, and the effect of the present invention may be significantly impaired. This is because the quenching of the fluorescence of the lanthanoid cation is inversely proportional to the sixth power of the distance between the cations.
o, Y. Et al. And references cited therein)
It is considered that this also corresponds to what is described in. The center-to-center distance of the lanthanoid cation can be measured, for example, by a transmission electron microscope (TEM, STEM, etc.). In such a measurement, the measurement may be made smaller than the actual center-to-center distance due to overlapping of particles projected in the depth direction, so that the measurement angle may be changed in the same field of view for accurate measurement. . The fluorescence intensity of the resin sheet obtained in the present invention is, for example, a relative light emission intensity of 2
~ 30, preferably about 3-20.

(Use of Resin Sheet) The resin sheet of the present invention has a wide range of uses utilizing its fluorescent ability. For example, when the resin sheet of the present invention is used for a backlight light guide plate for a display of a notebook computer or a mobile phone,
By adding an ultraviolet light component to the white light backlight light source, an improvement in luminance can be achieved, and if ultraviolet light is used as the light source, light emission with good color purity by only the fluorescence of the resin sheet of the present invention is possible. In the case of such a light guide plate application, an arbitrary scattering material such as an inorganic filler may be added in order to scatter and guide light in the plane direction. The thickness of the light guide plate is not limited, but is usually about 0.1 to 10 mm, preferably about 0.5 to 7 mm, and more preferably about 0.5 to 5 mm.

When the light source of a projection device such as a liquid crystal projector contains ultraviolet light, the illuminance in the visible region can be improved by providing the resin sheet of the present invention as a wavelength conversion plate in the optical path. The resin sheet of the present invention is capable of converting ultraviolet light in sunlight into visible to near-infrared light. Therefore, it can also be used as an agricultural film having a function of converting the ultraviolet region of the sunlight spectrum into a wavelength region useful for various stages of plant growth.

The light corresponding to the wavelength range useful in various stages of plant growth is red light (around 660 nm) for promoting germination and rooting, and far red light (around 730 nm) for suppressing germination and rooting. , Near-ultraviolet light that suppresses hypocotyl elongation (3
70 nm to 380 nm), blue light that provides phototropism (around 440 nm to 480 nm), far-red light that promotes petiole elongation (around 730 nm), 636 nm and 650 nm that promote greening (promotion of chlorophyll biosynthesis), and growth ( 430 nm and 670 nm (maximum wavelength), which promote photosynthesis, red and far-red light, which influences short-day and long-day photoperiod to promote or suppress flowering, phenolic and anthocyanin-based Examples include ultraviolet light that changes the color of fruits and flowers by increasing the pigment.

Rare earth complexes useful for these include Pr.
³⁺, Nd³⁺, Sm³⁺, Eu³⁺, Tb ³⁺, Dy³⁺, H
o³⁺, Er³⁺, Tm³⁺, Yb³⁺Trivalent lanthanoid positive
And those containing ions, among which Eu³⁺And Sm³⁺etc
And Tb that emit light in the red region³⁺And Dy³⁺Blue, etc.
Those including those that emit light in the yellow region are very suitable.
is there. The resin sheet of the present invention is used as an agricultural film.
Examples of suitable resin matrices when using
A vinyl resin is given. The resin sheet of the present invention
Utilizing long conversion capacity, in addition to the above,
Beverages such as windows and films for vehicles and aircraft, PET bottles, etc.
Useful as container film, spectacle lens coating, etc.
Used.

[0039]

EXAMPLES Hereinafter, specific embodiments of the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto unless it exceeds the gist thereof.
It is not limited by these examples. The reagents and solvents used in this example were those manufactured by Tokyo Chemical Industry Co., Ltd. without any particular purification.

[Apparatus and Conditions, etc.] (1) NMR: JNM-EX270 manufactured by JEOL Ltd.
Type FT-NMR (1 H: 270 MHz, ¹³ C: 67.8)
MHz) and the solvent was measured using deuterated chloroform. . (2) FT-IR: FT / IR- manufactured by JASCO Corporation
A cast film of a methylene chloride solution of the sample was prepared on a 8000 type FT-IR, salt crystal, and measured.

(3) Mass spectrum: Shimadzu Corporation
KOMPACT MALDI III type laser ionized TOF-MS manufactured by KOMPACT was used. 3 as matrix material
Cations were detected using indole acrylic acid.
The measured values were used without any cation correction or the like. (In principle, MALDI measurement is observed in a form in which alkali metal cations such as Na + and K + are added to the molecular peaks. For example, L
eon, J. et al. W. et al. Polym. Bull
l. 35, p. 449 (1995). (4) Xenon lamp: Xenon short arc lamp AXD-150-MFP (rated lamp input 150 W) manufactured by Oak Manufacturing Co., Ltd. was used as an excitation light source in order to evaluate the luminous ability of the manufactured sheet-like sample. Using. The light source was placed in a dark box, light was extracted from a hole having a diameter of 10 mm, and the sample was irradiated.

[Synthesis of polybenzyl ether dendrimer ligand] Commercially available 3,5-dihydroxybenzoic acid was heated to reflux with a catalytic amount of sulfuric acid in ethanol for about 2 days.
Ethyl 3,5-dihydroxybenzoate (hereinafter abbreviated as EDHB) was obtained by sequentially removing generated water. ED
HB was purified to a purity of 99% or more by recrystallization from methylene chloride. Then, Hawker, C.A.
J. et al; Am. Chem. Soc. , 11
2, 7638 (1990),
Third-generation dendritic benzyl bromide obtained by using 3-methylbenzyl bromide instead of benzyl bromide having a terminal structure (abbreviated as M [G-3] -Br)
With anhydrous potassium carbonate described in the same document and 18-crown-
The above EDH is obtained by an etherification reaction using 6 ethers.
B to form a fourth generation dendrimer having an ethyl ester group at the focal point (M [G-4] -CO
OEt). The same etherification reaction was performed on 3-methylbenzyl bromide itself and EDHB, and the first generation dendritic benzyl bromide (M [G
-1] -Br). These are ¹ H and ¹³ C
The formation was confirmed by the fact that a signal attributed to the ethyl ester was found in the -NMR spectrum and an absorption attributed to the carbonyl group of the ester was seen near 1720 cm ^{-1 in the} FT-IR spectrum.
These are dissolved in tetrahydrofuran (THF), and 10
A 30% by weight aqueous solution containing double equivalent of potassium hydroxide was added. Next, the minimum amount of methanol that makes the reaction solution uniform was added, and the mixture was heated under reflux for 6 hours. Thin layer chromatography (TL
After confirming the completion of the reaction in C), the mixture was added dropwise to an aqueous solution containing an excess of acetic acid with respect to the used potassium hydroxide while stirring under ice cooling. The obtained precipitate was extracted with methylene chloride, washed with water, dried and concentrated, and purified by silica gel column chromatography (developing solvent: methylene chloride / diethyl ether system). The product thus obtained contains ¹ H and ¹³ C-NM
No signal attributable to the ethoxy group was observed in the R spectrum, and the absorption attributable to the carbonyl group near 1700 cm ^-1 and the OH stretching vibration attributable to the carboxyl group were observed in the FT-IR spectrum. It was concluded that the raw material ethyl ester group was completely hydrolyzed and converted to a carboxyl group. Furthermore, since these products gave a single peak corresponding to the theoretical molecular weight in the MALDI-TOF mass spectrum, they do not substantially contain different impurities of the dendrimer generation which are difficult to detect by spectroscopic techniques such as NMR and IR. It was also confirmed that the product was of high purity (the fourth and first generation dendrimer carboxylic acids were hereinafter referred to as M [G-4]
-COOH, and M [G-1] -COOH, respectively).

[Polybenzyl ether dend of Tb3 +]
Synthesis of Limmer Complex] M [Gn] -COOH (n
= 4 or 1, 3 equivalents each) and terbium acetate (anhydride)
Tb (CHCOO)_Three(1 equivalent) in chlorobenzene
After heating and refluxing for 30 minutes with stirring, about half of the solvent was
Distilled off. New chlorobenzene in the same amount as the solvent removed
And reflux for 15 minutes.
I repeated it once. Finally, the solvent is completely removed under vacuum
After removal, vacuum drying for 12 hours to remove light brown glassy solid
Obtained. These products are:¹H-NMR spectrum
Does not give a signal derived from the acetyl group,
1700 cm in R spectrum^-1Nearby carvone
The absorption attributed to the carbonyl group of the acid
Without giving the O—H stretching vibration attributed to the sil group,
Elemental analysis value (oxide Tb_TwoO_ThreeAsh calculated as
) Coincided with the calculated value within 1% error.
Of terbium acetate is completely dendrimer
Substituted with a carboxylic acid and converted to the desired complex
(Hereinafter M [G-n]) _Three-Tb).

[Synthesis of Eu ³⁺ polybenzyl ether dendrimer complex] Europium acetate (anhydride) Eu (CHC) was prepared according to the above-mentioned synthesis procedure of M [Gn] ₃ -Tb.
OO) ₃ and M [G-4] -COOH as starting materials to obtain a light brown glassy solid. This is ¹ H-NMR
No signal derived from the acetyl group was given in the spectrum, and 1700 cm ^{-1 was found} in the FT-IR spectrum.
Absorption attributed to the carbonyl group of the nearby carboxylic acid,
Similarly, no OH stretching vibration attributed to the carboxyl group was given, and the elemental analysis values (including the ash calculated as oxide Eu ₂ O ₃ ) agreed with the calculated values within 1% error. It was concluded that the acetyl group of the raw europium acetate was completely substituted with dendrimer carboxylic acid and converted to the target complex (hereinafter referred to as M [G-4] ₃ −
Eu).

Example 1 M [G-
4] _3- Tb was dissolved in methyl methacrylate (MMA). However, the weight ratio of M [G-4] ₃ -Tb / MMA was 15/85. 50 parts by weight of this mixture is dried TH
F. 50 parts by weight of F, and 2 equivalents of tri-n-octylphosphine oxide are added to M [G-4] ₃ -Tb, and while blowing dry nitrogen and stirring, 2,2′-azobisisobutyronitrile is added. Was used as an initiator for 8 hours under a nitrogen stream under THF heating and reflux conditions. A part of the obtained solution was cast on a glass substrate having a thickness of about 1 mm under a dry nitrogen atmosphere to produce a film having a thickness of about 0.5 mm.

Example 2 The same operation as in Example 1 was performed using M [G-1] ₃ -Tb instead of M [G-4] ₃ -Tb. However, the concentration of Tb ³⁺ with respect to MMA was the same. Example 3 The remaining solution of Example 1 was stirred with TH
F was distilled off and further concentrated at 150 ° C. under reduced pressure to obtain a transparent resin composition from which volatile components were substantially removed. This was crushed into granules, and hot-pressed at 200 ° C. to form a transparent resin plate having a thickness of 5 mm.

Example 4 The same operation as in Example 3 was performed on the remaining solution of Example 2. Example 5 M [G-4] ₃ -Tb obtained as described above
Was dissolved in methyl methacrylate (MMA). However, the weight ratio of M [G-4] ₃ -Tb / MMA is 15/8.
It was set to 5. To this mixture, tri-n-octylphosphine oxide was added in an amount of 2 equivalents to M [G-4] ₃ -Tb,
2,2'-azobisisobutyronitrile was added to make a homogeneous solution. This was poured into a glass Petri dish and heated at 70 ° C. for 30 hours under a dry nitrogen stream to perform bulk polymerization, thereby producing a film.

Example 6 M [G-
4] _3- Tb was dissolved in chloroform, and Aldr
polyvinyl chloride (weight average molecular weight 1)
61,000, intrinsic viscosity 1.60) and dissolved.
However, the concentration of Tb3 + in the components excluding methylene chloride was 0.1% by weight. This solution was cast under a nitrogen atmosphere to produce a film having a thickness of about 0.1 mm.

Example 7 M [G-
4] _3- Eu was dissolved in chloroform, and Example 6 was added thereto.
Was added and dissolved. However, the concentration of Eu ^{3+ in} the components excluding methylene chloride was 0.1% by weight. This solution was cast under a nitrogen atmosphere to produce a film having a thickness of about 0.1 mm. This film and the film of Example 6 were overlaid with the film of Reference Example 4 interposed therebetween, and hot-pressed at 150 ° C. to obtain a three-layer laminated film.

Comparative Example 1 The same operation as in Example 1 was performed using a pivaloyltrifluoroacetone complex of Tb ³⁺ (hereinafter, PTA ₃ -Tb) instead of M [G-4] ₃ -Tb. Was. However, the concentration of Tb ³⁺ with respect to MMA was the same. Comparative Example 2 The same operation as in Example 3 was performed using the remaining solution of Comparative Example 1.

[Comparative Example 3] The same operation as in Example 5 was performed using a pivaloyltrifluoroacetone complex of Tb ³⁺ (hereinafter, PTA3-Tb) instead of M [G-4] ₃ -Tb. . However, the concentration of Tb3 + with respect to MMA was the same. [Comparative Example 4] PTA ₃ instead of M [G-4] ₃ -Tb
Using -Tb, the same operation as in Example 6 was performed to obtain a film. However, the concentration of Tb ^{3+ in} the components excluding methylene chloride was 0.1% by weight.

Reference Example 1 The polymerization of Example 1 was carried out using M [G-
4] Excluding _3- Tb, the same experiment as in Example 1 was performed on the obtained solution to obtain a film containing no complex. Reference Example 2 The same experiment as in Example 3 was performed using the remaining solution of Reference Example 1 to obtain a film containing no complex. [Reference Example 3] The bulk polymerization of Example 5 was performed using M [G-4] ₃ -T
The procedure was repeated except for b to obtain a complex-free film. [Reference Example 4] The procedure of Example 6 was carried out except for M [G-4] ₃ -Tb to obtain a film containing no complex.

[Evaluation 1] In a dark room, 45 μm of excitation light from the xenon lamp was applied to the surface of the sheet sample.
Irradiation was performed at an incident angle of 545 nm, and the emission intensity at 545 nm derived from Tb ³⁺ was observed in a direction perpendicular to the surface. Evaluation 1
Are summarized in Table 1 as relative intensities obtained by dividing the observed values of the examples by the observed values of the corresponding comparative examples. In addition, the observation value of the corresponding reference example is adopted as the background value,
The value subtracted from the actually measured value of the example and the comparative example was used for evaluation.

[0054]

Table 1 Experiment No. Phosphor Molding method Relative emission intensity (545 nm) Example 1 M [G-4] ₃ -Tb solution cast 11.8 Example 2 M [G-1] ₃ -Tb ４4 3.2 Example 3 M [G-4] ₃ -Tb hot press 8.9 Example 4 M [G-1] ₃ -Tb 〃 3.3 Example 5 M [G-4] ₃ -Tb Bulk polymerization 9 6.6 Example 6 M [G-4] 3-Tb solution cast 9.8 Comparative Example 1 PTA ₃ -Tb solution cast (1.0) Comparative Example 2 〃 Hot press (1.0) Comparative Example 3 〃 Bulk polymerization (1.0) Comparative Example 4 Solution casting (1.0)

[Evaluation 2] The method of Evaluation 1
When the emission spectrum of Lum was observed, Tb ³⁺Derived from
Emission bands (490 nm, 545 nm, and 583 n
m), and Eu³⁺Emission band (580 nm and
613 nm). These emission bands are
It is substantially the same as the spectral component of
Was. Further, with respect to the film of Example 7,
Observation of the excitation spectrum with the band as the observation wavelength,
290nm-320nm UV light as excitation light
It turned out to be. From these facts, the file of Example 7
Film transforms the ultraviolet region of sunlight into wavelengths suitable for growing plants.
It turns out that it is useful as a replacement agricultural film.

[0056]

The fluorescent resin sheet of the present invention has a high-luminance planar light-emitting function due to the extremely strong fluorescent ability of the rare-earth complex containing a ligand having a hyperbranched structure dispersed in the sheet. And excellent balance of mechanical properties. Further, since it can be easily produced by a known melt molding method, solution casting method, or the like, it can be used in the form of, for example, a light guide plate of a display, a wavelength conversion plate, an agricultural film, an ultraviolet light cut film, or the like.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 25/04 C08L 25/04 27/06 27/06 33/00 33/00 69/00 69/00 101/00 101/00 C09K 3/00 C09K 3/00 U 104 104Z 9/02 9/02 B 11/00 11/00 C G02B 5/20 G02B 5/20 5/22 5/22 // C07F 5/00 C07F 5/00 D

Claims (12)

[Claims] 1. A fluorescent resin sheet characterized in that a rare earth complex containing a ligand having a hyperbranched structure as a component is dispersed in a resin matrix. 2. The fluorescent resin sheet according to claim 1, wherein the hyperbranched structure has an aromatic ring. 3. The fluorescent resin sheet according to claim 1, wherein the hyperbranched structure has an aromatic ring at a focal point in the structure. 4. The fluorescent resin sheet according to claim 1, wherein in the ligand having a hyperbranched structure, the coordinating functional group is directly bonded to a focal point of the hyperbranched structure. 5. The ligand having a hyperbranched structure having a carboxyl group as a coordination functional group.
5. The fluorescent resin sheet according to any one of 4. 6. The fluorescent resin sheet according to claim 1, wherein the hyperbranched structure has a dendrimer structure. 7. The rare-earth complex as a rare-earth cation as T
The fluorescent resin sheet according to any one of claims 1 to 6, which has b3 ⁺ or Eu3 ⁺ . 8. The fluorescent material according to claim 1, wherein the resin matrix is at least one selected from the group consisting of an acrylic resin, a styrene resin, an aromatic polycarbonate resin, and a vinyl chloride resin. Resin sheet. 9. A backlight light guide plate for a display using the resin sheet according to claim 1. 10. A wavelength conversion plate for projection equipment using the resin sheet according to claim 1. An agricultural film using the resin sheet according to any one of claims 1 to 8. 12. An ultraviolet light cut film using the resin sheet according to claim 1.