JP2009158181A - Manufacturing method of surface light source device - Google Patents

Abstract

Provided is a manufacturing method capable of manufacturing a surface light source device having a good pasting surface shape and high light extraction efficiency without damaging an organic EL panel and without deteriorating elements of the panel.
An organic EL panel having an organic light emitting layer and a hollow sealing container, and a method of manufacturing a surface light source device including a resin film having a concavo-convex structure provided on a light exit surface side of the panel, the mold release Applying an adhesive functional resin on the film to obtain a laminate, moving the heated elastic roller and tensioning the unadhered portion of the laminate to press the laminate with a roller, and then applying the laminate to the adhesive layer and panel The process of sticking to the panel so that the surface of the light-emitting surface is in contact, the process of peeling the release film and exposing the adhesive layer, and moving the heated elastic roller and tensioning the unbonded part of the resin film The manufacturing method including the process of sticking a resin film on the surface of the contact bonding layer exposed by pressing a resin film with a roller.
[Selection] Figure 5

Description

  The present invention relates to a method for manufacturing a surface light source device.

  In general, an organic electroluminescence element (hereinafter sometimes referred to as an “organic EL element”) includes a substrate, an electrode layer and a light emitting layer formed on the substrate, and further degrades the layer such as the light emitting layer to the atmosphere. A sealing container is provided for protecting from. The inside of the device defined by the sealing container is generally hollow, and a layer such as a light emitting layer is present therein (see, for example, Patent Document 1).

  In the organic EL element, although the light emission efficiency in the element is high, there is a problem that it is difficult to improve the light extraction efficiency to the outside of the element. In order to improve the light extraction efficiency of the organic EL element, it has been reported that a concavo-convex structure is formed on the light extraction surface (see, for example, Patent Document 2). In order to facilitate the formation of a light emitting layer and the like, such a concavo-convex structure is formed by bonding a film having a concavo-convex structure on the light emitting surface side after forming an organic EL panel including a substrate, a light emitting layer, and a sealing container. It is common to provide by sticking through an agent.

JP 2007-12885 A JP 2007-273975 A

  When sticking such a film, it is necessary to make the sticking surface very good so that there is no optical loss. However, due to the change in dimensions due to the application and drying of the adhesive, the film tends to be warped and distorted, and the sticking surface is likely to be defective.

  Further, since the sealing container is hollow, if a high pressure is applied when the concavo-convex structure layer is applied to the organic EL panel, breakage such as cracking occurs. Therefore, the application needs to be performed at as low a pressure as possible. However, it is difficult to obtain a good surface shape when applied at a low pressure. In addition, since a normal light emitting layer has poor heat resistance, the pasting temperature needs to be as low as 80 ° C. or less. On the other hand, when the surface light source device is used, the temperature of the substrate increases due to light emission from the element, and therefore the heat-resistant temperature (flow temperature) of the adhesive needs to be as high as 50 ° C. or higher.

  Accordingly, an object of the present invention is to manufacture a surface light source device having a good pasting surface shape and high light extraction efficiency without damaging the organic EL panel and without degrading the elements of the organic EL panel. It is to provide a method.

  As a result of intensive studies to solve the above problems, the present inventors have transferred the adhesive layer onto the organic EL panel by a specific process, and further stuck a resin film having a concavo-convex structure thereon on the specific process. As a result, the inventors have found that the above-described problems can be solved, and completed the present invention.

That is, according to the present invention, the following is provided:
[1] An organic EL panel having an organic light-emitting layer, a hollow sealing container that accommodates the organic light-emitting layer, and a surface light source including a resin film having a concavo-convex structure provided on the light-emitting surface side of the organic EL panel A method for manufacturing an apparatus, wherein step (A): a step of applying an adhesive functional resin on a release film to obtain a laminate (1) having a release film and an adhesive layer, step (B): heated elasticity While the body roller is moved and the unbonded portion of the laminate (1) is tensioned, the laminate (1) is pressurized with the roller, and the laminate (1) is combined with the adhesive layer and the organic Step of attaching to the organic EL panel such that the surface on the light exit surface side of the EL panel is in contact, step (C): peeling the release film and exposing the adhesive layer, and step (D): heating Moving elastic roller The resin having the concavo-convex structure is exposed on the exposed surface of the adhesive layer by pressing the resin film having the concavo-convex structure with the roller while tensioning an unbonded portion of the resin film having the concavo-convex structure. The manufacturing method of the surface light source device which includes the process of sticking a film and whose contact pressure in pressurization of the said elastic body roller is 0.5 Mpa or less.
[2] The manufacturing method, wherein the material of the elastic roller is silicon rubber or fluororubber.

  According to the manufacturing method of the present invention, a surface light source device having a good pasting surface shape and high light extraction efficiency without damaging the organic EL panel and without degrading the elements of the organic EL panel. Can do.

Below, the manufacturing method of this invention is demonstrated concretely with reference to drawings.
The present invention relates to a method of manufacturing a surface light source device, and the surface light source device includes an organic EL panel having an organic light emitting layer and a hollow sealing container, and unevenness provided on the light emitting surface side surface of the organic EL panel. A resin film having a structure is provided.

  An example of a surface light source device that can be manufactured by the manufacturing method of the present invention will be described with reference to FIG. In FIG. 6, the surface light source device 600 includes a transparent substrate 241, a sealing container composed of a sealing substrate 251 and a peripheral sealing member 252, and a transparent electrode 261 provided in a gap 263 defined by these, An organic EL panel 610 having a light emitting layer 271 and a reflective electrode 262, and an adhesive layer 131 and a resin film 491 provided on the light outgoing surface side surface 241 e of the substrate 241 are provided. The light exit surface 491e of the resin film 491 is provided with an uneven structure (not shown in FIG. 6).

  Light is generated from the light emitting layer 271 by applying a voltage from the electrodes 261 and 262 to the light emitting layer 271, and this is reflected directly or after being reflected by the reflective electrode 262, and then the transparent electrode 261, the substrate 241, the adhesive layer 131, and the resin film. Light is transmitted through 491. Thus, in the surface light source device in which the light emitting layer is laminated on the substrate, the light extraction efficiency is improved by adopting an aspect in which light from the light emitting layer is emitted through the substrate and the resin film having the concavo-convex structure. be able to.

  The uneven shape of the resin film 491 having an uneven structure can be a conical shape, a pyramid shape, or a prism shape. For example, as shown in FIG. 7, the pyramid shape can be a shape in which square weights 941 having a square bottom surface are arranged without gaps, but are not limited to the example shown in FIG. 7, and are triangular, pentagonal, hexagonal, A pyramid such as a weight and a square weight whose bottom surface is not square can be formed in a shape in which no pyramids are arranged with no gaps or flat gaps.

  Furthermore, the cone and the pyramid as used in the present application include not only a normal cone and a pyramid having a pointed top but also a shape having a rounded tip or a flat chamfered shape. This will be described with reference to FIGS. FIG. 9 is a partial cross-sectional view of the square weight 941 in FIG. 7 cut along a plane that passes through the line 9a and is parallel to the normal lines of the slopes 941a and 941b of the square weight 941 and perpendicular to the surface direction of the substrate. In the example of FIG. 9, the apex 1153 of the triangular pyramid has a sharp shape, but this may have a rounded shape like the apex 1255 shown in FIG. 10. Further, as shown in FIG. 11, a flat portion 1355 may be provided at the top of the pyramid to form a flat chamfered shape.

  When the top of the pyramid has a rounded shape, the height difference 1257 between the top 1255 and the top 1253 when the pyramid has a sharp shape without being rounded indicates that the pyramid is rounded. The height can be 20% or less of the height 1258 of the pyramid when it has a sharp shape. When the apex of the pyramid has a flat chamfered shape, the height difference 1357 between the flat portion 1355 and the apex 1353 when the apex of the pyramid is not flat but sharp is given by the pyramid. 20% or less of the height 1358 of the pyramid in the case where the top part of the pyramid is not flat but has a sharp shape.

  Although the dimension of the concavo-convex structure is not particularly limited, the maximum value (Ra (max)) of the center line average roughness measured along various directions can be in the range of 1 to 50 μm.

  On the other hand, the prism shape in the case where the concavo-convex structure 110 has a prism shape is a shape in which prisms such as triangular prisms are arranged so that the height direction of the prisms is parallel to the light exit surface, for example, as shown in FIG. In addition, the shape of the prism row 1040 in which a plurality of linear prisms 1041 are arranged in parallel can be used. However, the shape is not limited thereto, and for example, the shape of the apex 1042 is a pointed shape as in the case of the pyramid. Not only can it be a rounded shape or a flat chamfered shape.

  In the present invention, the angle formed by the conical, pyramidal, or prismatic slope and the light exit surface is preferably 45 to 60 °. For example, when the concavo-convex structure is a quadrangular pyramid shown in FIG. 7, the apex angle (corner 1151 in FIG. 9) is preferably 60 to 90 °. When the top of the concavo-convex composition has a rounded shape or a flat chamfered shape, the angle of the inclined surface excluding the portion of the shape is a pyramid or prism-shaped inclined surface. For example, in the example shown in FIGS. 10 and 11, the planes 1241a, 1241b, 1341a, and 1341b are pyramid slopes. By setting the angle of the slope to such an angle, the light extraction efficiency can be increased. The slopes of the light exit surface of the concavo-convex structure layer are not necessarily all at the same angle, and slopes having different angles may coexist within the above range. The angle formed between the conical slope and the light exit surface can be the angle formed between the generatrix of the cone and the light exit surface.

  In the present invention, examples of the material constituting the light-emitting surface side substrate include glass and resin. The refractive index of the substrate on the light exit surface side is preferably close to that of the transparent resin layer, and can be 1.5 to 1.6. In the present invention, the thickness of the substrate is not particularly limited, but is preferably 100 μm to 3 mm. On the other hand, as a material constituting the sealing container, glass, metal, resin, and an adhesive for bonding the sealing substrate and the light-emitting surface substrate are used for the sealing substrate and the peripheral agent.

  In the present invention, the light-emitting layer constituting the light-emitting element in the organic EL panel is not particularly limited and can be appropriately selected from known ones. A combination of types of layers can emit white or near-color light. The electrode is not particularly limited, and a known electrode can be appropriately selected. Further, other layers such as a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and a gas barrier layer can be further provided between the electrodes in addition to the light emitting layer.

Although it does not specifically limit as a material which comprises an electrode and the layer provided among them, The following can be mentioned as a specific example.
ITO etc. can be mentioned as a material of a transparent electrode.
Examples of the material for the hole injection layer include a starburst aromatic diamine compound.
Examples of the material for the hole transport layer include triphenyldiamine derivatives.
Examples of the host material for the yellow light-emitting layer include triphenyldiamine derivatives, and examples of the dopant material for the yellow light-emitting layer include tetracene derivatives.
Examples of the host material for the blue light emitting layer include anthracene derivatives, and examples of the dopant material for the blue light emitting layer include perylene derivatives.
Examples of the material for the red light emitting layer include europium complexes.
Examples of the material for the electron transport layer include an aluminum quinoline complex (Alq).
Examples of the cathode material include lithium fluoride and aluminum, which are sequentially stacked by vacuum film formation.

  By appropriately combining the above or other light-emitting layers, a light-emitting layer that generates a light emission color having a complementary color relationship, which is referred to as a stacked type or a tandem type, can be obtained. The combination of complementary colors can be yellow / blue, green / blue / red, or the like, whereby white light emission suitable for the light source application can be obtained.

  In the example shown in FIG. 6, a transparent electrode 261, a light emitting layer 271 and a reflective electrode 262 are provided on a transparent substrate 241 in this order to constitute a so-called bottom emission type light emitting element that emits light through the substrate. However, the present invention is not limited to this, and a top emission type light emitting element may be configured.

  In the production method of the present invention, first, an adhesive functional resin is applied on a release film to obtain a laminate (1) having a release film and an adhesive layer (step (A)). FIG. 1 is a cross-sectional view schematically showing an example of such a laminate (1). As shown in FIG. 1, an adhesive functional resin is applied on the surface of the release film 121, and then a drying process or the like is performed as necessary, thereby forming an adhesive layer 131, and the release film 121 and the adhesive layer 131. A laminate (1) made of can be obtained.

  In the present invention, as a material for the release film, a material that easily peels the adhesive layer in the next step can be appropriately selected, and it may be a transparent material or an opaque material. Specifically, for example, if the resin adhesive has a polar group, polyethylene, polypropylene film which is a nonpolar polymer, if it is a resin adhesive having a nonpolar group, PET, PMMA which is a polar polymer, or the material of the adhesive Regardless of the above, there may be mentioned polytetrafluoroethylene which is a fluorine compound polymer or a film whose surface is fluorinated.

  As the adhesive functional resin applied on the release film, a heat melting type resin that is welded by heating and hardened by cooling can be used, and a glass transition temperature (Tg) of 50 to 80 ° C. is preferable. By setting the glass transition temperature to 50 ° C. or higher, a surface light source device having sufficient heat resistance can be obtained. On the other hand, by setting the glass transition temperature to 80 ° C. or lower, the light emitting layer of the organic EL panel can be stuck without damaging it. Can do.

  The adhesive functional resin is a conjugated diene polymer cyclized product obtained by cyclization reaction of a conjugated diene polymer, and the conjugated diene polymer cyclized product with respect to an unsaturated bond in the conjugated diene polymer. A conjugated diene polymer cyclized product having an existing unsaturated bond reduction rate (unsaturated bond reduction rate) of 30% or more can be used. Moreover, as said adhesive function resin, what contains the said conjugated diene polymer cyclization thing and alicyclic olefin resin can also be used.

  The conjugated diene polymer cyclized product is obtained by subjecting a conjugated diene polymer to a cyclization reaction in the presence of an acid catalyst. As the conjugated diene polymer, homopolymers and copolymers of conjugated diene monomers and copolymers of conjugated diene monomers and monomers copolymerizable therewith can be used.

  The conjugated diene monomer is not particularly limited, and specific examples thereof include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 1, Examples include 3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, and 3-butyl-1,3-octadiene. These monomers may be used alone or in combination of two or more.

  Specific examples of conjugated diene polymers include homopolymers or copolymers of conjugated dienes such as natural rubber, polyisoprene, and butadiene-isoprene copolymers; styrene-butadiene copolymers, styrene-isoprene copolymers, isoprene. -Aromatic vinyl-conjugated diene block copolymer such as isobutylene copolymer, ethylene-propylene-diene copolymer rubber, styrene-isoprene block copolymer, etc. And a copolymer with the body. Among these, natural rubber, polyisoprene, and styrene-isoprene block copolymer are preferable, and polyisoprene and styrene-isoprene block copolymer are more preferable.

  As the conjugated diene polymer cyclized product, a modified conjugated diene polymer cyclized product modified with a polar group is preferably used. The modified conjugated diene polymer cyclized product exhibits adhesion to the adherend of the resin composition for a light emitting device containing the same, and when the resin composition for a light emitting device contains fine particles, There is an effect of improving dispersibility. One kind of the modified conjugated diene polymer cyclized product containing a polar group may be contained in the resin composition for a light emitting device, and a plurality of types having different polar groups may be contained in the resin composition for a light emitting device. It may be included. Further, a conjugated diene polymer cyclized product having two or more kinds of functional groups may be used.

  The polar group is not particularly limited, and examples thereof include an acid anhydride group, carboxyl group, hydroxyl group, thiol group, ester group, epoxy group, amino group, amide group, cyano group, silyl group, and halogen. Can be mentioned.

  Examples of the acid anhydride group or carboxyl group include maleic anhydride, itaconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, vinyl carboxylic acid compounds such as acrylic acid, methacrylic acid, and maleic acid. Examples include a group having a structure added to a cyclized product of a polymer, and among them, a group having a structure in which maleic anhydride is added to a cyclized product of a conjugated diene polymer is preferable in terms of reactivity and economy.

  Amide group is introduced by grafting conjugated diene polymer cyclized product using unsaturated compound containing amide group; introducing functional group using unsaturated compound containing functional group Then, it can be introduced by a method of reacting the introduced functional group with a compound having an amide group. Examples of the unsaturated compound containing an amide group include acrylamide, N-isopropylacrylamide, N, N-dimethylacrylamide, and N-benzylacrylamide.

  Examples of the hydroxyl group include hydroxyalkyl esters of unsaturated acids such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate, N-methylol (meth) acrylamide, and N- (2 -Unsaturated acid amides having hydroxyl groups such as hydroxyethyl) (meth) acrylamide, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, and poly (ethylene glycol-propylene glycol) mono (meth) acrylate Groups of structures in which polyalkylene glycol monoesters of unsaturated acids such as, and polyhydric alcohol monoesters of unsaturated acids such as glycerol mono (meth) acrylate are added to the conjugated diene polymer cyclized product, This Among al, hydroxyalkyl esters of unsaturated acids are preferred, particularly 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate is a group of the structure obtained by adding the conjugated diene polymer cyclized product preferred.

  Examples of vinyl compounds containing other polar groups include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl ( And (meth) acrylate, (meth) acrylamide, and (meth) acrylonitrile.

  The content of the polar group in the modified conjugated diene polymer cyclized product, particularly the polar group-containing conjugated diene polymer cyclized product is not particularly limited, but is usually 0.1 to 15 mol%, preferably 0.5 to 10 mol. %, More preferably in the range of 1 to 7 mol%. If the content is too small or too large, the oxygen absorption function tends to be inferior. In addition, content of a polar group makes 1 mol the molecular weight equivalent amount of the polar group couple | bonded with the molecule | numerator of a modified conjugated diene polymer cyclization thing.

  As a method for producing a modified conjugated diene polymer cyclized product, (1) a method in which a conjugated diene polymer cyclized product obtained by the above-described method is subjected to an addition reaction with a polar group-containing vinyl compound, and (2) a polar group is contained. A method of obtaining a conjugated diene polymer by cyclization reaction by the above-mentioned method, (3) An addition reaction of a vinyl compound containing a polar group to a conjugated diene polymer not containing a polar group, followed by a cyclization reaction. And (4) a method of further adding a polar group-containing vinyl compound to the product obtained by the method (2) or (3). Especially, the point of said (1) is preferable from the point which can adjust an unsaturated bond decreasing rate more easily.

  The polar group-containing vinyl compound is not particularly limited as long as it is a compound that can introduce a polar group into a conjugated diene polymer cyclized product. For example, an acid anhydride group, a carboxyl group, a hydroxyl group, a thiol group, Preferred examples include vinyl compounds having polar groups such as ester groups, epoxy groups, amino groups, amide groups, cyano groups, silyl groups, and halogens.

  Examples of the vinyl compound having an acid anhydride group or a carboxyl group include maleic anhydride, itaconic anhydride, aconitic anhydride, norbornene dicarboxylic acid anhydride, acrylic acid, methacrylic acid, and maleic acid. Maleic anhydride can be preferably used in terms of reactivity and economy. As a vinyl compound containing a hydroxyl group, for example, hydroxyalkyl esters of unsaturated acids are preferable, and 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate are particularly preferable vinyl compounds.

  The method for adding a polar group-containing vinyl compound to a conjugated diene polymer cyclized product and introducing a polar group derived from the polar group-containing vinyl compound is not particularly limited, but is generally an ene addition reaction or a graft polymerization reaction. What is necessary is just to follow the well-known reaction called. This addition reaction is carried out by contacting the conjugated diene polymer cyclized product with the polar group-containing vinyl compound in the presence of a radical generator, if necessary. Examples of the radical generator include peroxides such as di-tert-butyl peroxide, dicumyl peroxide, and benzoyl peroxide, and azonitriles such as azobisisobutyronitrile.

  The conjugated diene polymer cyclized product has at least two kinds of unsaturated bonds, ie, a linear unsaturated bond inherent to the conjugated diene and a cyclic unsaturated bond of the cyclized portion, except for a 100% cyclized product. ing. In the conjugated diene polymer cyclized product, it is considered that the cyclic unsaturated bond portion greatly contributes to oxygen absorption, and the linear unsaturated bond portion hardly contributes to oxygen absorption. Therefore, a conjugated diene polymer cyclized product having a reduction rate of unsaturated bonds (unsaturated bond reduction rate) in the conjugated diene polymer cyclized product with respect to unsaturated bonds in the conjugated diene polymer of 30% or more is It is essential as a material for the oxygen absorbing member in the light emitting device of the invention. The unsaturated bond reduction rate of the conjugated diene polymer cyclized product is preferably 40 to 75%, more preferably 55 to 70%. If the unsaturated bond reduction rate is too low, oxygen absorption tends to deteriorate. The conjugated diene polymer cyclized product prevents the conjugated diene polymer cyclized product from becoming brittle by making the unsaturated bond reduction rate less than or equal to the upper limit of the above preferred range, facilitates production, and causes gelation during production. Progression is suppressed, transparency is improved, and it can be used for many purposes. Further, if the unsaturated bond reduction rate exceeds 50%, adhesiveness is exhibited, and this property can be utilized.

Here, the unsaturated bond reduction rate is an index representing the degree to which the unsaturated bond is reduced by the cyclization reaction in the conjugated diene monomer unit site in the conjugated diene polymer, and is a numerical value obtained as follows. is there. That is, by proton NMR ( ¹ H-NMR) analysis, in the conjugated diene monomer unit portion in the conjugated diene polymer, the ratio of the peak area of protons directly bonded to double bonds to the peak area of all protons is Calculate the reduction rate before and after the chemical reaction.

Now, in the conjugated diene polymer unit site in the conjugated diene polymer, the total proton peak area before the cyclization reaction is SBT, the peak area of the proton directly bonded to the double bond is SBU, and the total proton after the cyclization reaction When the peak area is SAT and the peak area of the proton peak directly bonded to the double bond is SAU, the peak area ratio (SB) of the proton directly bonded to the double bond before the cyclization reaction is SB = SBU / SBT, The peak area ratio (SA) of the proton directly bonded to the double bond after the cyclization reaction is expressed as SA = SAU / SAT. Therefore, the unsaturated bond reduction rate is
Unsaturated bond reduction rate (%) = 100 × (SB−SA) / SB
As required.

  The oxygen absorption amount of the conjugated diene polymer cyclized product used in the present invention is 5 ml / g or more, preferably 10 ml / g or more, more preferably 50 ml / g or more. The oxygen absorption amount is the amount of oxygen absorbed by 1 g of the conjugated diene polymer cyclized product when the conjugated diene polymer cyclized product is sufficiently absorbed as a powder or thin film to reach a saturated state at 23 ° C. If the amount of oxygen absorbed is small, a large amount of conjugated diene polymer cyclized product is required to stably absorb oxygen for a long period of time. The amount of oxygen absorbed is mainly correlated with the unsaturated bond reduction rate in the conjugated diene polymer cyclized product.

In the present invention, the conjugated diene polymer cyclized product used has an oxygen absorption rate from the surface of 1.0 ml / m ² · day or more, preferably 5.0 ml / m ² · day or more, more preferably 10 ml / m ^2. -More than a day. Even if the conjugated diene polymer cyclized product has a large oxygen absorption ability, if the oxygen absorption rate is too slow, oxygen entering from the outside may not be sufficiently absorbed and transmitted. Further, when used as a sealing container of a light emitting element, oxygen that has existed or has invaded in the sealed space for some reason must be quickly absorbed and removed by the conjugated diene polymer cyclized product layer. From this point of view, those having the above-described oxygen absorption rate are desirable.

  The content of the conjugated diene polymer cyclized product in the adhesive functional resin is usually 5 to 90% by weight, preferably 15 to 70% by weight. When the content of the conjugated diene polymer cyclized product is lower than the lower limit value, there may be a disadvantage that the oxygen absorption capacity and the adhesion force at room temperature (25 ° C.) are lowered. There is a possibility that the strength is lowered.

  The alicyclic olefin resin is an amorphous resin having an alicyclic structure such as a cycloalkane structure or a cycloalkene structure in the main chain and / or side chain. From the viewpoint of mechanical strength and heat resistance, a polymer containing an alicyclic structure in the main chain is preferred. Examples of the alicyclic structure include monocycles and polycycles (condensed polycycles, bridged rings, etc.). Among the alicyclic structures, a cycloalkane structure is preferable. The number of carbon atoms constituting one unit of the alicyclic structure is not particularly limited, but is usually 4-30, preferably 5-20, more preferably 5-15. Various properties such as mechanical strength, heat resistance, and moldability are highly balanced and suitable. Specific examples of the alicyclic olefin resin include (1) norbornene polymer, (2) monocyclic olefin polymer, (3) cyclic conjugated diene polymer, and (4) vinyl alicyclic hydrocarbon. Examples thereof include a polymer and a mixture thereof. Among these, a norbornene polymer and a vinyl alicyclic hydrocarbon polymer are preferable from the viewpoints of optical properties, heat resistance, and mechanical strength. Further, when an alicyclic olefin resin having a polar group is used as the alicyclic olefin resin, the affinity with an inorganic substance can be improved without impairing the light transmittance.

(1) Norbornene polymer The norbornene polymer used in the present invention includes a ring-opening polymer of a norbornene monomer, a ring-opening copolymer of a norbornene monomer and other monomers capable of ring-opening copolymerization, and hydrides thereof. Addition polymers of norbornene monomers, addition copolymers of norbornene monomers and other monomers copolymerizable therewith, and the like. Examples of the norbornene monomer include bicyclo [2.2.1] -hept-2-ene (common name: norbornene) and its derivatives (having a substituent in the ring), and tricyclo [4.3.1 ^2,5 . 0 ^1,6 ] -deca-3,7-diene, tetracyclo [7.4.1 ^10,13 . 0 ^1,9 . 0 ^2,7 ] -trideca-2,4,6,11-tetraene, tetracyclo [4.4.1 ^2,5 . 1 ^7,10 . 0] -dodecaene and derivatives having a substituent on these rings. Examples of the substituent present in the ring include an alkyl group, an alkylene group, a vinyl group, and an alkoxycarbonyl group. The norbornene monomer may have two or more of these. These norbornene monomers may be used alone or in combination of two or more. Examples of other monomers capable of ring-opening copolymerization with norbornene monomer include monocyclic olefin monomers such as cyclohexene, cycloheptene, and cyclooctene. These other monomers copolymerizable with the norbornene monomer can be used alone or in combination of two or more. In the case of addition copolymerization of a norbornene monomer and another monomer copolymerizable therewith, the ratio of the structural unit derived from the norbornene monomer and the structural unit derived from the other monomer copolymerizable in the addition copolymer is The weight ratio is appropriately selected so as to be in the range of 30:70 to 99: 1, preferably 50:50 to 97: 3, more preferably 70:30 to 95: 5. Other monomers capable of addition copolymerization with norbornene monomer include α-olefins having 2 to 12 carbon atoms such as ethylene, propylene, 1-butene; styrenes such as styrene and α-methylstyrene; 1,3-butadiene. And chain conjugated dienes such as isoprene; and vinyl ethers such as ethyl vinyl ether.

(2) Monocyclic Cyclic Olefin Polymer As the monocyclic cycloolefin polymer, for example, an addition polymer of a monocyclic cycloolefin monomer such as cyclohexene, cycloheptene, and cyclooctene can be used.

(3) Cyclic conjugated diene polymer Examples of the cyclic conjugated diene polymer include a polymer obtained by subjecting a cyclic conjugated diene monomer such as cyclopentadiene and cyclohexadiene to 1,2- or 1,4-addition polymerization, and hydrogen thereof. A compound or the like can be used.

(4) Vinyl alicyclic hydrocarbon polymer As the vinyl alicyclic hydrocarbon polymer, for example, polymers of vinyl alicyclic hydrocarbon monomers such as vinyl cyclohexene and vinyl cyclohexane and their hydrides, Examples thereof include hydrides of aromatic ring portions of polymers obtained by polymerizing vinyl aromatic monomers such as styrene and α-methylstyrene, and vinyl alicyclic hydrocarbon monomers and vinyl. Examples thereof include hydrides of copolymers of aromatic monomers and other monomers copolymerizable with these monomers.

  Examples of the polar group in the alicyclic olefin resin having a polar group include a polar group containing an oxygen atom, a nitrogen atom, a sulfur atom, and a silicon atom, and a halogen atom. From the viewpoints of compatibility and compatibility with other resins, polar groups containing oxygen atoms, nitrogen atoms, and the like are preferred. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfone group.

  In the present invention, among these alicyclic olefin resins, norbornene polymers are preferable, addition copolymers of norbornene monomers and α-olefins are more preferable, and addition copolymers of norbornene monomers and ethylene are particularly preferable. preferable.

  The content of the alicyclic olefin resin in the adhesive functional resin is usually 10 to 80% by weight, preferably 15 to 70% by weight. When the content of the alicyclic olefin resin is less than the lower limit value, mechanical strength may be lowered. When the upper limit value is exceeded, the oxygen absorption capacity at room temperature (25 ° C.) is reduced. Inconvenience may occur.

The adhesive functional resin may contain a moisture absorbing resin, an inorganic desiccant, a heat dissipating fine powder, various additives, and the like.
As other adhesive functional resin, polyolefin modified with a polar substance such as maleic anhydride is used. Polyolefin is a thermoplastic resin that excels in various properties such as thermal stability, chemical resistance, and weather resistance (especially linear polyethylene or polypropylene). On the other hand, it is a highly versatile resin, with polar functional groups in the molecule. Therefore, the physical properties such as adhesiveness and printability are remarkably inferior, and the range of use is limited.
There is a method of graft polymerization of maleic anhydride to compensate for the above-mentioned drawbacks of polyolefin. For this, a method of performing graft polymerization by irradiating γ-rays, X-rays or high-speed electron beams, a method of using a graft polymerization initiator such as peroxide, and the like are used. Of these, the method using peroxide is often advantageous in that it does not require special equipment during the reaction, and is a widely used method. As the peroxide, benzoyl peroxide, t-butyl peroxybenzoate, or the like is generally used.

  The method of applying the adhesive functional resin onto the release film is not particularly limited, and methods such as bar coating, spin coating, spray coating, and gravure coating can be employed. An adhesive layer can be obtained by forming a coating film by these methods and further performing a treatment such as drying as necessary. The thickness of the adhesive layer is preferably 100 μm or less, and more preferably 50 μm or less. The lower limit of the thickness of the adhesive layer can be set to 0.1 μm or more, for example.

  In the production method of the present invention, subsequently, the laminated body (1) is pressurized with the roller while moving the heated elastic roller and tensioning the unbonded portion of the laminated body (1), The laminate (1) is attached to the organic EL panel so that the adhesive layer and the surface on the light emitting surface side of the organic EL panel are in contact with each other (step (B)).

  This process will be described with reference to FIGS. FIG. 2 is a cross-sectional view schematically illustrating an example of the sticking process, and FIG. 3 is a cross-sectional view schematically illustrating an example of a structure in a state where the sticking is completed.

  In the example shown in FIG. 2, the heated roller 281 is moved in the direction of the arrow 283a, and the laminate (1) composed of the release film 121 and the adhesive layer 131 is released on the surface 241e on the light exit surface side of the substrate 241. The film is attached while pressing in the direction of arrow 283b from the film 121 side. In FIG. 2, the state at the time when the region 291d of the adhesive layer 131 is already bonded and the regions 291t and 291u are bonded is illustrated.

  By using a vacuum chuck device 282 having a through hole or formed of a porous material, air is sucked in the direction of the arrow 284a, whereby the region 291u of the laminate (1) is held by the vacuum chuck device 282, and the vacuum By applying tension to the layered product (1) in the direction of the arrow 283c by the chuck device 282, the region (291t), which is an unbonded portion of the layered product (1), is tensioned by the roller 281. Can be pressurized. The suction of the vacuum chuck device 282 can be interlocked with the movement of the roller 281. That is, as the roller 281 moves in the direction of the arrow 283a, the suction of the portion of the vacuum chuck device 282 that the roller 281 is approaching is released, so that the tension direction 283c is set to a constant angle, and the tension tension is reduced. Can be kept constant.

  With this pasting, as shown in FIG. 3, a structure in which the adhesive layer 131 and the release film 121 are laminated in this order on the surface 241 e on the light exit surface side of the substrate 241 of the organic panel 610 is obtained.

  In this step, an elastic roller is used as the roller. The elastic body here refers to a rubber-like material having a Young's modulus of 0.1 Gpa or less. The elastic roller does not necessarily have to be an elastic body, and only the portion where the roller contacts the object to be pressed may be an elastic body. For example, a roller having a structure in which the outer periphery of a non-elastic metal cylinder is covered with an elastic body is also included in the elastic body roller. The elastic body is preferably heat resistant. To be heat resistant means that pressurization at a heating temperature described later is possible. As such an elastic body, specifically, materials such as silicon rubber and fluorine rubber can be used. By using such an elastic roller, when the roller comes into contact with the resin film, the contact area with the film becomes large, and it is possible to heat efficiently even if the contact pressure is relatively low.

  The heating temperature of the roller is preferably a temperature at which the temperature of the adhesive surface of the adhesive layer (the surface of the adhesive layer 131 in contact with the substrate 241 in the example of FIG. 2) is in the range of 50 to 80 ° C. By setting the sticking temperature to 80 ° C. or lower, the sticking can be performed without causing deterioration of the light emitting layer, and by setting the sticking temperature to 50 ° C. or higher, sticking suitable for the above-mentioned adhesive layer can be performed. The temperature of the roller itself changes as the adhesive surface temperature of the adhesive layer changes according to the moving speed of the roller (the higher the moving speed, the lower the adhesive surface temperature). be able to. The moving speed of the roller is not uniform depending on the material of the film, but can be 10 to 1,000 mm / min.

  The contact pressure in pressing the roller is preferably 0.5 MPa or less. By setting the contact pressure within this range, it is possible to prevent the occurrence of distortion in the hollow portion of the sealing container, and thus prevent the sealing container and the transparent substrate from being damaged. The lower limit of the contact pressure is not particularly limited, but can be 0.01 MPa or more.

  As shown in the above example, the direction of applying tension when the unbonded portion of the laminate (1) is tensioned is perpendicular to the rotation axis of the roller and on the light emitting surface side of the organic EL panel to be pasted. It can be a direction having a predetermined angle with the surface. Such a predetermined angle can be 0 to 50 °. Moreover, although the tension | tensile_strength at the time of applying tension is not uniform with the material of a film, it can be set to 1-100 Mpa.

  By sticking as described above, it is possible to stick while the adhesive layer is melted by heat while minimizing the temperature rise of the light emitting layer. It can be provided on the organic EL panel without accompanying.

  In the production method of the present invention, subsequently, the release film is peeled off to expose the adhesive layer (step (C)). As a result, for example, as in the example shown in FIG. 4, it is possible to obtain a structure in which the adhesive layer 131 having the exposed surface 131e is provided on the light emitting surface side surface 241e of the organic EL panel 610.

  In the production method of the present invention, subsequently, the heated elastic roller is moved and the unbonded portion of the resin film having the uneven structure is tensioned, and the resin film having the uneven structure is pressed with the roller. Then, the resin film having the concavo-convex structure is pasted on the exposed surface of the adhesive layer (step (D)).

  This process will be described with reference to FIGS. FIG. 5 is a cross-sectional view schematically illustrating an example of the pasting process, and FIG. 6 is a cross-sectional view schematically illustrating an example of the structure of the organic EL panel in a state where the pasting is completed.

  In the example shown in FIG. 5, the heated roller 481 is moved in the direction of the arrow 483a, and the resin film 491 having a concavo-convex structure is formed on the surface 131e of the adhesive layer 131 that has been covered with the release film. It is stuck while pressing in the direction of arrow 483b from the 491e side. FIG. 5 illustrates a state at the time when the region 491d of the resin film 491 has already been bonded and the regions 491t and 491u are to be bonded.

  By using a vacuum chuck device 482 having a through hole or formed of a porous material, air is sucked in the direction of arrow 484a, thereby holding the region 491u of the resin film 491 with the vacuum chuck device 482. By applying tension to the resin film 491 in the direction of the arrow 483 c at 482, the resin film 491 can be pressed by the roller 481 while tensioning the region 491 t that is an unbonded portion of the resin film 491. The suction of the vacuum chuck device 482 can be interlocked with the movement of the roller 481. That is, as the roller 481 moves in the direction of the arrow 483a, the suction of the portion of the vacuum chuck device 482 where the roller 481 approaches is released, so that the tension direction 483c is set to a constant angle, and the tension tension is reduced. Can be kept constant.

  With this pasting, as shown in FIG. 6, a surface light source device 600 is obtained in which an adhesive layer 131 and a resin film 491 having a concavo-convex structure are laminated in this order on the surface 241 e on the light exit surface side of the substrate 241 of the organic panel 610. be able to.

  In this step, an elastic roller is used as the roller. As such an elastic roller, the same roller as that used in the step (B) can be used.

  The heating temperature of the roller is preferably a temperature at which the temperature of the adhesive surface of the adhesive layer (in the example of FIG. 5, the surface of the adhesive layer 131 that contacts the resin film 491) is in the range of 50 to 80 ° C. . By setting the sticking temperature to 80 ° C. or lower, the sticking can be performed without causing deterioration of the light emitting layer, and by setting the sticking temperature to 50 ° C. or higher, sticking suitable for the above-mentioned adhesive layer can be performed. The roller operating conditions such as moving speed and contact pressure can be the same as those in the step (B).

  As shown in the above example, the direction in which the unbonded portion of the resin film having a concavo-convex structure is tensioned is perpendicular to the rotation axis of the roller and the light emitting surface side of the organic EL panel to be pasted And a direction having a predetermined angle. Such a predetermined angle can be 0 to 50 °. Moreover, although the tension | tensile_strength at the time of applying tension is not uniform with the material of a film, it can be set to 1-100 Mpa.

  By sticking as described above, it is possible to stick a resin film having a concavo-convex structure while fusing the adhesive layer while minimizing the temperature rise of the light emitting layer, and to form a layer having a uniform concavo-convex structure without wrinkles. The organic EL panel can be provided on the organic EL panel without being damaged or deteriorated.

  Although the use of the surface light source device obtained by the manufacturing method of the present invention is not particularly limited, it can be used as a light source of a lighting device or a backlight of a display device such as a liquid crystal display device.

The present invention is not limited to the exemplification of the above-described embodiment, and can be modified within the scope of the claims of the present application and its equivalent scope.
For example, although only one layer of the adhesive layer and the resin film having the concavo-convex structure is provided on the organic EL panel, a step of further providing other layers as necessary may be included. Such other layers can be stuck on the organic EL panel by a method using a roller or the like, as in the case of the resin film having the adhesive layer and the uneven structure.

  Hereinafter, the present invention will be described in more detail based on examples. In addition, this invention is not limited to the following Example.

<Example 1>
(1-1: Organic EL panel)
On a glass substrate having a thickness of 1 mm, a transparent electrode layer 100 nm, a hole transport layer 10 nm, a yellow light emitting layer 20 nm, a blue light emitting layer 15 nm, an electron transport layer 15 nm, an electron injection layer 1 nm, and a reflective electrode layer 100 nm were sequentially formed. The hole transport layer to the electron transport layer are all organic materials. The first to second light emitting layers have different emission spectra.

The material forming each layer from the transparent electrode layer to the reflective electrode layer is as follows:
-Transparent electrode layer; tin-added indium oxide (ITO)
Hole transport layer: 4,4′-bis [N- (naphthyl) -N-phenylamino] biphenyl (α-NPD)
・ Yellow light emitting layer: 1.5% by weight of rubrene added α-NPD
Blue light-emitting layer; iridium complex added by 10% by weight 4,4′-dicarbazolyl-1,1′-biphenyl (CBP)
-Electron transport layer; phenanthroline derivative (BCP)
-Electron injection layer; lithium fluoride (LiF)
-Reflective electrode layer: Al

The transparent electrode layer was formed by a reactive sputtering method using an ITO target, and the surface resistance was 10Ω / □ or less. In addition, the formation method from the hole injection layer to the reflective electrode layer is that a glass substrate on which a transparent electrode layer has already been formed is installed in a vacuum evaporation apparatus, and the material from the hole injection layer to the reflective electrode layer is formed by resistance heating. This was done by sequentially depositing. The system internal pressure was 5 × 10 ⁻³ Pa and the evaporation rate was 0.1 to 0.2 nm / s.

  Furthermore, wiring for energization was attached to the electrode layer, and the hole injection layer to the reflective electrode layer were sealed with a sealing member to obtain an organic EL panel. As shown in FIG. 6, the sealing is performed by attaching a sealing container including the peripheral sealing member 252 and the sealing substrate 251 to the substrate 241, and between the reflective electrode 262 and the sealing substrate 251. A void was provided.

(1-2: Production of laminate (1); Step (A))
A polyethylene resin (cycloolefin polymer) having a glass transition temperature of 60 ° C. having a polar group is coated on a polyethylene terephthalate (PET) film with a bar coater, dried at 100 ° C., and an adhesive layer having a thickness of 20 μm on the PET film. A laminate (1) having the following was obtained.

(1-3: Pasting of laminate (1); step (B))
On the surface of the substrate of the organic EL panel obtained in 1-1, the laminate (1) obtained in 1-2 was attached. The sticking is performed by moving the heated elastic body roller 281 and tensioning the unbonded portion 291t of the laminated body (1) with the vacuum chuck device 282, as shown in FIG. Pressurized at 281. The direction of the laminate (1) was such that the adhesive layer 131 of the laminate (1) was in contact with the surface 241e on the light emitting surface side of the organic EL panel. By linking the suction of the vacuum chuck device 282 with the movement of the roller 281, the angle formed by the tensioning direction 283 c and the surface 241 e was kept within a range of 40 to 50 °. Moreover, the tension when applying tension was set to 10 MPa. A roller made of silicon rubber was used. The contact pressure of the roller was 0.4 MPa, and the moving speed was 70 mm / min. It was 70 degreeC when the temperature on the contact bonding layer in the case of sticking was measured with the thermo label.

(1-4: Release of release film; step (C))
Subsequently, the release film was peeled off to expose the adhesive layer, and a structure having the organic EL panel 610 and the adhesive layer 131 as shown in FIG. 4 was obtained.

(1-5: Resin film having an uneven structure)
A ZEONOR film (manufactured by ZEON Corporation) in which regularly arranged microlenses (diameter 80 μm) were formed was produced by a thermal imprint method. That is, it was manufactured by heating a nickel mold on which a microlens was formed at 150 ° C. and pressing it on a ZEONOR film.
The thickness of the obtained resin film was 100 μm, and unevenness of a microlens having a diameter of 80 μm was formed on one surface thereof.

(1-6: Affixing a resin film having an uneven structure; Step (D))
The surface light source device as shown in FIG. 6 was obtained by pasting the resin film having the concavo-convex structure obtained in 1-5 on the surface 131e of the structure obtained in 1-4 where the adhesive layer was exposed. . As shown in FIG. 5, the sticking is performed by pressing the resin film 491 with the roller 481 while moving the heated elastic roller 481 and tensioning the unbonded portion 491 t of the resin film 491 with the vacuum chuck device 482. It was done. The resin film 491 was oriented so that the surface of the resin film opposite to the surface having the concavo-convex structure was in contact with the surface 131e of the adhesive layer 131. By linking the suction of the vacuum chuck device 482 with the movement of the roller 481, the angle formed by the tensioning direction 483c and the surface 241e was kept within a range of 40 to 50 °. Moreover, the tension when applying tension was set to 10 MPa. The same vacuum chuck device and roller as those used in the above 1-3 were used. The contact pressure of the roller was 0.4 MPa, and the moving speed was 70 mm / min. It was 70 degreeC when the temperature on the contact bonding layer in the case of sticking was measured with the thermo label.

(1-7: Evaluation)
The surface light source device obtained in 1-6 above was evaluated from the following viewpoints.

(I) Adhesiveness The adhesive force with which the obtained resin film having a concavo-convex structure on the surface light source device adheres to the substrate was determined by a cross-cut method (JIS K5400). Specifically, 10 × 10 cuts are made into the test piece at 1 mm intervals with a cutter knife, and a cellophane adhesive tape is brought into close contact therewith, and the end of the tape is kept at 90 degrees from the test piece and peeled off instantaneously. The peeled state at that time was evaluated in three stages: o: no peeling, Δ: partial peeling, x: all peeling.

(Ii) Planar surface The surface light source device was energized and observed, and the presence or absence of wrinkles on the light exit surface, remaining bubbles and deterioration of the light emitting layer were observed.
The observation results are shown in Table 1.

<Comparative Example 1>
In the above 1-3 and 1-6, except that the contact pressure of the roller was set to 0.9 MPa, the surface light source device was produced and evaluated in the same manner as in Example 1. The results are shown in Table 1.

<Comparative example 2>
The same polyolefin resin as that used in Step 1-2 of Example 1 on the same surface of the resin film having a concavo-convex structure as that obtained in Step 1-5 of Example 1 is used. It was applied and dried, and an adhesive layer having a thickness of 20 μm was provided. This was affixed on the surface of the same organic EL panel substrate as obtained in Step 1-1 under the same conditions as in Step 1-6 of Example 1 to produce a surface light source device. The obtained surface light source device was evaluated in the same manner as in Example 1. The results are shown in Table 1.

  As is clear from the results in Table 1, the surface light source device of Example 1 obtained by the manufacturing method of the present invention has strong adhesion of the resin film having the concavo-convex structure, and deterioration of the element and poor film adhesion. None of the panel defects were observed, and a good surface light source device could be obtained as compared with Comparative Examples 1 and 2 in which any of the manufacturing processes was outside the scope of the present invention.

It is sectional drawing which shows typically an example of the laminated body (1) prepared in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the process (B) in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the structure of the state which completed the process (B) in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the structure of the state which completed the process (C) in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the process (D) in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the structure of the state which completed the process (D) in the manufacturing method of this invention. It is a perspective view which shows typically the shape of an example of the resin film which has the uneven structure used in the manufacturing method of this invention. It is a perspective view which shows typically the shape of another example of the resin film which has the uneven structure used in the manufacturing method of this invention. It is sectional drawing which shows typically an example of the uneven | corrugated shape in the resin film shown in FIG. It is a perspective view which shows typically the shape of another example of the unevenness | corrugation of the resin film which has the uneven structure used in the manufacturing method of this invention. It is a perspective view which shows typically the shape of another example of the unevenness | corrugation of the resin film which has the uneven structure used in the manufacturing method of this invention.

Explanation of symbols

121 Release Film 131 Adhesive Layer 241 Substrate 251 Sealing Substrate 252 Peripheral Sealing Member 261 Transparent Electrode 262 Reflective Electrode 263 Gap 271 Light-Emitting Layer 281, 481 Roller 282, 482 Vacuum Chuck Device 491 Resin Film Having Uneven Structure 600 Surface Light Source Device 610 Organic EL panel 941 Square pyramid 941a, 941b Square pyramid slope 1040 Prismatic row 1041 Linear prism 1042 Linear prism apex 1153 Triangular pyramid apex 1255 Triangular pyramid apex 1355 Triangular pyramid apex Flat part

Claims (2)

Manufacture of a surface light source device comprising: an organic light emitting layer; an organic EL panel having a hollow sealed container that accommodates the organic light emitting layer; and a resin film having a concavo-convex structure provided on a light exit surface side of the organic EL panel A method,
Step (A): A step of applying an adhesive functional resin on a release film to obtain a laminate (1) having a release film and an adhesive layer,
Step (B): The laminated body (1) is pressed with the roller while moving the heated elastic roller and the unbonded portion of the laminated body (1) is tensioned, and the laminated body (1) Is attached to the organic EL panel so that the adhesive layer and the surface on the light emitting surface side of the organic EL panel are in contact with each other,
Step (C): peeling the release film and exposing the adhesive layer; and Step (D): moving the heated elastic roller and tensioning the unbonded portion of the resin film having the concavo-convex structure. And pressing the resin film having the concavo-convex structure with the roller, and affixing the resin film having the concavo-convex structure on the exposed surface of the adhesive layer, and pressing the elastic roller The manufacturing method of the surface light source device whose contact pressure in is 0.5 Mpa or less. The manufacturing method according to claim 1,
The manufacturing method whose material of the said elastic body roller is silicon rubber or fluororubber.

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