JP6025300B2 - Method for producing optical laminate - Google Patents

Description

  The present invention relates to an optical laminate manufacturing method, an optical laminate, and a surface light source device including the same.

Conventionally, an organic EL display device provided with an ultraviolet absorption layer has been proposed in order to prevent the organic electroluminescence (EL) element from being deteriorated by ultraviolet rays (Patent Document 1).
In addition, in order to improve the light extraction efficiency from the light emitter in the organic EL element to the outside of the apparatus, studies have been made to form a prism sheet on the light exit surface of the organic EL element (Patent Document 2). In Patent Document 2, using a so-called 2P (photopolymer) method, an ultraviolet curable resin is disposed between a base material and a mold on which a predetermined concavo-convex structure is formed, and ultraviolet light is applied to the photocurable resin. A method for producing a prism sheet by irradiating and curing the resin is disclosed. The 2P method has an advantage that a layer having a complex uneven structure on the surface can be formed with high productivity.

JP 2007-103028 A International Publication No. 2009/081750

  However, in the 2P method, when ultraviolet curable resin is cured using ultraviolet rays, it is necessary to irradiate ultraviolet rays through the base material and other layers if present from the opposite side of the resin layer. is there. Therefore, when a material such as a base material containing an ultraviolet absorber is used to prevent the deterioration of the organic EL element, the arrival of ultraviolet rays to the ultraviolet curable resin is hindered and productivity is lowered. When the illuminance of ultraviolet rays is increased in order to increase productivity, deterioration (discoloration, deformation, etc.) of the base material and other layers due to ultraviolet rays and heat tends to occur.

  If the ultraviolet absorber is added to the resin to be cured without adding the ultraviolet absorber to the substrate, the ultraviolet rays can reach the resin to be cured without being blocked by the ultraviolet absorber. However, in this case, non-uniformity in the amount of ultraviolet rays is generated in the thickness direction of the resin to be cured, which is disadvantageous in giving a complicated shape to the resin to be cured. In addition, when an ultraviolet absorber that absorbs UVA (315 to 380 nm), which is required to be absorbed for preventing deterioration of the organic EL element, is added, there is a problem that the resin to be cured is colored and the aesthetic appearance of the apparatus is impaired.

  Accordingly, an object of the present invention is to improve the light extraction efficiency of an organic EL element, and to provide an optical laminate that can be implemented with high productivity for an optical laminate that is excellent in aesthetics and has a high ultraviolet absorption function. The present invention also provides an optical laminate and a surface light source device manufactured by the manufacturing method.

As a result of studying the above-described problems in order to solve the above-described problems, the present inventors have found that the above-described problems can be solved by forming optical function layers for improving light extraction efficiency in a specific order. Completed the invention.
That is, according to the present invention, the following is provided.

[1] a base material;
An optical functional layer provided on the front surface of the substrate;
A method for producing an optical laminate comprising: an adhesive layer having an ultraviolet absorption function provided on a back surface of the base material;
A step (A) of forming the optical functional layer on the surface of the substrate and obtaining a multilayer (a) having the substrate and the optical functional layer;
And a step (C) of providing the adhesive layer on the back surface of the multilayer (a).
[2] A method for producing an optical laminate according to [1],
The step (A)
A step (A1) of applying an ultraviolet curable uncured resin to the surface of the base material to form a layer of the uncured resin;
A step (A3) of bringing a mold having an uneven structure into contact with the uncured resin layer;
Irradiating ultraviolet rays from the back side of the base material to cure the uncured resin layer and obtaining an optical functional layer made of the cured resin (A4);
And (A5) a step of peeling the mold from the optical functional layer.
[3] A method for producing an optical laminate according to [2],
The manufacturing method of the optical laminated body which further includes the process (A2) of heating the layer of the said non-hardened resin after completion | finish of the said process (A1) and before the start of the said process (A4).
[4] The method for producing an optical laminate according to any one of [1] to [3],
The optical laminate further comprises a separator provided on the side of the adhesive layer opposite to the base material,
The manufacturing method further includes a step (B) of forming an adhesive layer having the ultraviolet absorption function on the separator, and obtaining a multilayer (b) having the separator and the adhesive layer,
The manufacturing method of an optical laminated body whose said process (C) is a process of bonding the said multilayer object (a) and the said multilayer object (b).
[5] A method for producing an optical laminate according to any one of [1] to [4],
The manufacturing method of the optical laminated body whose transmittance | permeability of the light of wavelength 365nm of the said base material is 80% or more.
[6] The method for producing an optical laminate according to any one of [1] to [5],
The manufacturing method of the optical laminated body in which the said base material contains the film which consists of alicyclic structure containing polymer resin whose weight average molecular weight is 35,000 or more.
[7] A method for producing an optical laminate according to any one of [1] to [6],
The manufacturing method of the optical laminated body in which at least any one of the said base material, the said optical function layer, and the said contact bonding layer contains the particle | grains which provide light diffusibility.
[8] An optical laminate produced by the method for producing an optical laminate according to any one of [1] to [7].
[9] A surface light source device including an organic electroluminescent element, wherein the optical functional layer and the base material are formed using the optical layered body according to [8] on the light-emitting surface side of the organic electroluminescent element. And a surface light source device further comprising an adhesive layer.

  In the production method of the present invention, the object of the present invention is to improve the light extraction efficiency of the organic EL device, to improve the optical laminate of the present invention having excellent aesthetics and a high ultraviolet absorption function with high productivity. Can be implemented.

  The surface light source device of the present invention can improve the light extraction efficiency of the organic EL element, has excellent aesthetics, has high durability based on a high ultraviolet absorption function, and can be manufactured with high productivity.

FIG. 1 is a perspective view schematically showing an example of the optical layered body of the present invention manufactured by the manufacturing method of the present invention. FIG. 2 is a cross-sectional view showing a cross section of the optical laminate shown in FIG. 1 cut along a plane passing through line 1a-1b. FIG. 3: is sectional drawing which shows roughly the example of the cross section of the multilayer body which consists of a base material and the layer of uncured resin obtained by process (A1). FIG. 4 is a cross-sectional view schematically showing an example of a cross section in a state where the mold contact is performed in the step (A3). FIG. 5 is a schematic diagram showing a more specific aspect of performing steps (A3) to (A5). FIG. 6: is sectional drawing which shows roughly the example of the cross section of the multilayered product (a) which consists of a base material and an optical function layer after performing peeling in a process (A5). FIG. 7 is a cross-sectional view schematically showing the multilayered product (b) obtained by the step (B). FIG. 8 is a partial top view schematically showing an enlarged structure of the surface 10U of the optical functional layer 111 shown in FIGS. FIG. 9 is a partial cross-sectional view showing a cross section of the optical functional layer 111 taken along a plane that passes through the line 10a of FIG. 8 and is perpendicular to the main surface of the optical laminate. FIG. 10 is a perspective view schematically showing an example of the surface light source device of the present invention. FIG. 11 is a cross-sectional view showing a cross section of the surface light source device 10 shown in FIG. 10 cut along a plane that passes through the line 1a-1b in FIG. 11 and is perpendicular to the surface direction of the substrate.

〔Overview〕
The manufacturing method of the present invention comprises a base material, an optical functional layer provided on the front side surface of the base material, and an adhesive layer having an ultraviolet absorption function provided on the back side surface of the base material. The manufacturing method of the optical laminated body further equipped with the separator provided in the opposite side to the said base material of the said contact bonding layer. The manufacturing method of the present invention is an optical laminate obtained by such a manufacturing method.

  FIG. 1 is a perspective view schematically showing an example of the optical layered body of the present invention manufactured by the manufacturing method of the present invention, and FIG. 2 passes through the optical layered body shown in FIG. 1 along lines 1a-1b. It is sectional drawing which shows the cross section cut | disconnected by the surface. The optical laminated body 100 shown in FIG. 1 has a structure in which a separator 141, an adhesive layer 131, a base material 121, and an optical functional layer 111 are laminated in this order, and the surface 10U of the optical functional layer 111 has concave portions 113 and concave portions. 113 has a concavo-convex structure composed of a flat portion 114 located around the periphery of 113.

  The production method of the present invention includes the step (A) of forming the optical functional layer on the surface on the front side of the base material to obtain a multilayer (a) having the base material and the optical functional layer, and the multilayer And (C) providing the adhesive layer on the back surface of the object (a).

[Process (A)]
In the step (A), the optical functional layer is formed on the front surface of the substrate. The optical functional layer can be formed as a layer in direct contact with the surface on the front side of the substrate. In the present application, the “front side” of the base material simply indicates that it is relative to the back side of the base material (that is, the side of the base material on which the adhesive layer is provided) relative to the convenience of explanation. In the following description, unless otherwise specified, the front side of the base material is shown as the upper surface of the base material, and the back side is shown and described as the lower surface.
In the step (A), the optical functional layer can be formed by forming a layer of an ultraviolet curable uncured resin on a substrate and curing it to obtain a layer having a desired shape. Specifically, step (A) is:
A step (A1) of applying an ultraviolet curable uncured resin to the front surface of the substrate to form a layer of the uncured resin;
A step (A3) of bringing a mold having an uneven structure into contact with the uncured resin layer;
-A step (A4) of obtaining an optical functional layer made of a cured resin by irradiating ultraviolet rays from the back side of the base material to cure the uncured resin layer;
A step (A5) of peeling the mold from the optical functional layer.

More specific examples of the steps (A1), (A3), (A4) and (A5) will be described with reference to FIGS.
FIG. 3: is sectional drawing which shows roughly the example of the cross section of the multilayer body which consists of a base material and the layer of uncured resin obtained by process (A1). FIG. 4 is a cross-sectional view schematically showing an example of a cross section in a state where the mold contact is performed in the step (A3). FIG. 5 is a schematic diagram showing a more specific aspect of performing steps (A3) to (A5). FIG. 6: is sectional drawing which shows roughly the example of the cross section of the multilayered object (a) which consists of a base material and an optical function layer after performing peeling in a process (A5).

First, as shown in FIG. 3, as a step (A1), an ultraviolet curable uncured resin is applied to the front surface 12U of the substrate 121 to form a layer 116 of the uncured resin.
The method for applying the uncured resin is not particularly limited, and a known application method can be employed. Specific coating methods include wire bar coating, dipping, spraying, spin coating, roll coating, gravure coating, lip coating, die coating, capillary coating, air knife coating, and curtain coating. , Slide coating method, extrusion coating method and the like. The coating amount of the uncured resin is not particularly limited, but can be adjusted so that the thickness of the optical functional layer obtained after curing becomes a desired thickness.

  After performing the step (A1), the step (A2) of heating the uncured resin layer can be optionally performed. Specifically, the heating can be performed by heating the uncured resin layer together with the base material using a device such as a hot air heater or an infrared heater. The lower limit of the heating temperature range is preferably 30 ° C. or higher, more preferably 50 ° C. or higher. On the other hand, the upper limit is preferably 120 ° C. or lower, more preferably 90 ° C. or lower. The lower limit of the heating time can be 10 seconds or more, more preferably 30 seconds or more. On the other hand, the upper limit is preferably 10 minutes or less, more preferably 5 minutes or less. By performing such heating, the adhesion between the substrate and the optical functional layer can be improved. The step (A2) can be performed before the step (A4) is carried out, but is preferably carried out before the step (A3) is carried out, particularly from the viewpoint of ease of work.

When the step (A2) is performed after the step (A1) or before the start of the step (A3) after the completion of the step (A1), the step (A3) can be performed after the step (A2). . The step (A3) can be performed by bringing the mold 101 having a concavo-convex structure into contact with the uncured resin layer 116 as shown in the example of FIG. The mold 101 can be brought into contact with the surface 11U on the upper side of the uncured resin layer 116 (that is, the side opposite to the side on which the base material 121 is in contact). By this contact, an uneven structure can be imparted to the upper surface 11U of the uncured resin layer 116.
As a mold used in the step (A3), a mold having a desired shape can be used. Further, by using a roll having a roll shape, an optical laminate having a long shape can be produced in-line with high efficiency. The production of a mold having a roll shape includes a method of directly forming a desired mold on the roll and a method of fixing a mold formed on a belt-like metal or plastic to the roll. From the viewpoint of cost, a method of fixing a mold made of a belt-shaped material to a roll is preferable.

  In the step (A3), when the mold is brought into contact with the uncured resin layer, it is preferable to apply pressure to the uncured resin layer and the substrate so as to press them against the mold. Specifically, in the example shown in FIG. 4, a nip roll is applied to the lower surface 12L of the substrate 121, and pressure can be applied to press the uncured resin layer and the substrate in the direction of the mold 101. . By performing such pressurization, the shape of the upper surface of the uncured resin layer can be made to follow the shape of the mold well, and an optical functional layer having a high-quality concavo-convex structure can be obtained.

  More specifically, the step (A3) is preferably performed continuously using a roll-shaped mold and a nip roll because production efficiency can be improved. Specifically, as shown in the example of FIG. 5, the multilayer body having the uncured resin layer 116 and the base material 121 is conveyed in the direction of the arrow A5 and passed between the roll-shaped mold 101 and the nip roll 51, The step (A3) can be achieved by applying pressure so that the nip roll 51 presses the multilayer structure against the mold 101.

When the step (A2) is performed after the step (A3) or before the start of the step (A4) after the completion of the step (A3), the step (A4) can be performed after the step (A2). . In the step (A4), ultraviolet rays are irradiated from the back side of the substrate to cure the uncured resin layer and obtain an optical functional layer made of the cured resin.
Referring back to the example of FIG. 4, such ultraviolet rays are emitted from the light source on the lower side of the base material 121 toward the back surface 12 </ b> L of the base material 121. The irradiated ultraviolet rays pass through the substrate 121 and reach the uncured resin layer 116, thereby curing the uncured resin layer 116. As a result, the uncured resin layer 116 is cured and becomes an optical functional layer.

  In the case where the step (A3) is continuously performed using a roll-shaped mold and a nip roll, the step (A4) includes a step in which a multilayer having an uncured resin layer and a substrate is in contact with the roll-shaped mold. However, it can be performed at a stage away from the nip roll. Referring to FIG. 5 again, the step (A4) can be performed in a region 52 where the multilayered material conveyed in the direction of arrow A5 is separated from the nip roll 51 but is in contact with the mold 101. . Thereby, efficient production can be performed. Moreover, in order to perform a process (A4) more effectively, you may apply | coat a mold release agent to the surface of a type | mold beforehand. As the release agent, silicon-based, fluorine-based, and fatty acid-based agents can be used.

  The wavelength of the ultraviolet rays irradiated in the step (A3) can be appropriately selected from wavelengths that can cure the uncured resin. For example, a wavelength suitable for the wavelength at which the photopolymerization initiator contained in the uncured resin can react, and a wavelength that can be easily used as a wavelength that a commercially available ultraviolet irradiation device and a commercially available ultraviolet absorber can be used. Can be appropriately selected.

If the wavelength is too short, damage to the substrate is likely to occur. On the other hand, if the wavelength is too long, it may approach the visible region and cause coloring of the layer, etc., so light in the wavelength region of 340 nm to 400 nm is preferably used. it can. More specifically, ultraviolet rays including a wavelength of 365 nm can be used. The lower limit of the irradiation amount of ultraviolet rays is preferably 300 mJ / cm ² or more, and more preferably 500 mJ / cm ² or more. On the other hand, the upper limit is preferably at 5000 mJ / cm ² or less, more preferably 3000 mJ / cm ² or less.

  After performing the step (A4), by performing the peeling of the step (A5), as shown in FIG. 5, a multilayered product (a) having the base material 121 and the optical functional layer 111 formed on the upper side thereof, as shown in FIG. Can be obtained. When a roll having a roll shape is adopted as the mold used in the steps (A3) to (A5), the step (A5) is simply the rotation of the roll mold and the multilayer in the steps (A3) to (A5). This can be achieved by continuing the conveyance of the object.

  The multilayered product (a) obtained by the step (A) can be wound up in a roll shape as necessary and stored until used in the step (C). Prior to winding, if necessary, a protective film can be further stacked on the surface of the optical functional layer side to reduce damage on the surface of the optical functional layer due to winding.

  In the multilayered product (a) obtained by the step (A), an optional layer can be further formed as necessary before being subjected to the step (C). For example, a layer that can be optionally provided, such as a hard coat layer, can be provided on the surface of the multilayered product (a) on the optical functional layer side as necessary.

[Process (B)]
The production method of the present invention can optionally further include a step (B) of forming an adhesive layer having an ultraviolet absorbing function on the separator to obtain a multilayer (b) having the separator and the adhesive layer. FIG. 7 is a cross-sectional view schematically showing the multilayered product (b) obtained by the step (B). In FIG. 7, an adhesive layer 131 is formed on the upper surface 14U of the separator 141, whereby a multilayer (b) having the separator 141 and the adhesive layer 131 is obtained. The adhesive layer can be formed by applying an adhesive to form an adhesive layer, and subjecting it to a treatment such as drying as necessary.

  The laminate (b) obtained in the step (B) is preferably immediately subjected to the next step (C) for simplification of the step. However, the laminate (b) is wound into a roll as necessary, and the step (C). It can also be stored until used. In the case of winding, usually, prior to winding, a second separator can be further stacked on the surface on the adhesive layer side to protect the adhesive layer.

[Process (C)]
In the step (C), an adhesive layer is provided on the back side surface of the multilayer (a). The adhesive layer can be formed as a layer in direct contact with the back side surface of the base material, but before the start of the step (C) after the completion of the step (A), an arbitrary layer is formed on the back side surface of the base material. When provided, it can be provided on that layer.

  In step (C), an adhesive layer is directly formed on the back surface of the multilayer (a) by the same method as described in step (B) above, or an adhesive layer formed on another layer. Can be carried out by sticking to the back surface of the multilayer (a).

  When the step (B) is performed, the step (C) can be performed by laminating the multilayer product (a) and the multilayer product (b). Bonding is usually performed on the base material side surface of the multilayer object (a) (the lower surface 12L of the base material 121 in the example of FIG. 5) and the adhesive layer side surface of the multilayer object (b) ( In the example of FIG. 6, it can carry out by making the upper surface 13U) of the contact bonding layer 131 contact, and pressing with a nip roll as needed.

  In the present invention, by performing the step (A) prior to the step (C), an optical laminate having a function of improving light extraction efficiency and a high ultraviolet absorption function can be produced with high productivity.

  That is, in the production method of the present invention, the layer having an ultraviolet absorbing function is used as an adhesive layer, and the adhesive layer is provided on the substrate surface opposite to the optical functional layer after forming the optical functional layer. In the formation of the functional layer, ultraviolet irradiation is not hindered by the layer having an ultraviolet absorbing function. Therefore, it is possible to perform ultraviolet irradiation with high efficiency in forming the optical functional layer, and the optical functional layer can be formed with high productivity.

  In particular, in the production method of the present invention, as the step (A), by using the method including the steps (A1), (A3), (A4) and (A5) above, the optical functional layer having a concavo-convex structure is formed into 2P. It can be formed with high accuracy by the method, and the implementation of the 2P method is not hindered by the layer having an ultraviolet absorption function. More specifically, an optical layered body capable of effectively absorbing ultraviolet rays in a wide wavelength range including a wavelength range of UVA (315 to 380 nm) that degrades the organic EL element light emitting layer is convenient for the implementation of the 2P method. Therefore, it is possible to efficiently manufacture using ultraviolet rays around 365 nm. Therefore, it is possible to achieve both a high optical function, a high productivity, and an ultraviolet absorption function of the product.

[Optional process]
The manufacturing method of this invention can include arbitrary processes other than process (A)-(C). For example, prior to the step (A), the surface on the front side of the substrate can be subjected to any easy adhesion treatment such as corona treatment. Prior to the step (C), the surface on the back side of the substrate can be subjected to any easy adhesion treatment such as corona treatment.

  Moreover, in the manufacturing method of this invention, arbitrary layers can be formed in addition to the base material, the optical functional layer, the adhesive layer, and the separator described above. For example, an inorganic barrier layer, an antistatic layer, a hard coat layer, a conductivity imparting layer, and a contamination preventing layer can be formed. These arbitrary layers can be provided by a method such as a method in which the material is applied on a desired surface and cured, or a method in which the material is applied by thermocompression bonding.

  Below, the material used for the manufacturing method of this invention and the specific example of each layer formed with the manufacturing method of the optical laminated body of this invention are demonstrated.

〔Base material〕
As a base material used for this invention, the arbitrary films (henceforth a "base film") which can be used as a base material of an optical laminated body can be used. Alternatively, a multilayer product including a base film and an arbitrary layer such as an easy-adhesion layer and an antistatic layer can be used as the base material.
As an example of the material of the base film, specifically, from the viewpoints of adhesion with an easy-adhesion layer and other adjacent layers, strength as a member of an optical laminate, transparency, etc. In addition to the polymer resin, polyester, polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polycarbonate, and (meth) acrylic resin can be mentioned.

[Base film: Polymer resin containing alicyclic structure]
The alicyclic structure-containing polymer resin is a resin containing an alicyclic structure-containing polymer and other optional components as required.

  The alicyclic structure-containing polymer has an alicyclic structure in the main chain and / or side chain, and is usually an amorphous thermoplastic polymer. Examples of the alicyclic structure in the alicyclic structure-containing polymer include a saturated alicyclic hydrocarbon (cycloalkane) structure and an unsaturated alicyclic hydrocarbon (cycloalkene) structure. From the viewpoint, a cycloalkane structure is preferable. The number of carbon atoms constituting the alicyclic structure is not particularly limited, but is usually 4 to 30, preferably 5 to 20, more preferably 5 to 15, when the mechanical strength, heat resistance, In addition, the moldability characteristics of the film are highly balanced and suitable.

  The ratio of the repeating unit having an alicyclic structure constituting the alicyclic structure-containing polymer is preferably 55% by weight or more, more preferably 70% by weight or more, and particularly preferably 90% by weight or more. It is preferable from a viewpoint of transparency and heat resistance that the ratio of the repeating unit which has an alicyclic structure in an alicyclic structure containing polymer exists in this range.

  Examples of the alicyclic structure-containing polymer include norbornene polymers, monocyclic olefin polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and hydrides thereof. Among these, norbornene polymers can be suitably used because of their good transparency and moldability.

Examples of the norbornene polymer include a ring-opening polymer of a monomer having a norbornene structure, a ring-opening copolymer of a monomer having a norbornene structure and another monomer, or a hydride thereof; norbornene structure Or an addition copolymer of a monomer having a norbornene structure with another monomer, or a hydride thereof. Among these, a ring-opening (co) polymer hydride of a monomer having a norbornene structure is particularly suitable from the viewpoints of transparency, moldability, heat resistance, low hygroscopicity, dimensional stability, lightness, and the like. Can be used.
As the alicyclic structure-containing polymer, the alicyclic structure-containing polymer resin may contain only one kind of these polymers alone, or may contain two or more kinds in combination at any ratio. Also good.

The molecular weight of the alicyclic structure-containing polymer contained in the alicyclic structure-containing polymer resin can be appropriately selected according to the purpose of use. The molecular weight of the alicyclic structure-containing polymer is converted to polyisoprene measured by gel permeation chromatography using cyclohexane as a solvent (however, if the polymer does not dissolve in cyclohexane, toluene may be used). (When the solvent is toluene, it can be defined by the weight average molecular weight (Mw) of polystyrene conversion). From the viewpoint of highly balancing the mechanical strength and molding processability of the substrate, the lower limit of the weight average molecular weight is usually 10,000 or more, preferably 15,000 or more, more preferably 20,000 or more. be able to. On the other hand, the upper limit of the weight average molecular weight is usually 100,000 or less, preferably 80,000 or less, more preferably 50,000 or less.
In particular, the lower limit of the weight average molecular weight of the alicyclic structure-containing polymer is particularly preferably 35,000 or more in order to improve the handleability in the production method of the present invention. Specifically, by having a molecular weight equal to or higher than the lower limit, the brittleness is reduced, thereby causing damage to the substrate when winding up after the completion of the step (A) or peeling the separator from the optical laminate. It is particularly preferable because it can reduce receiving.

Examples of optional components that can be contained in the alicyclic structure-containing polymer resin include antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, antistatic agents, dispersants, chlorine scavengers, flame retardants, and crystals. Nucleating agents, reinforcing agents, antiblocking agents, antifogging agents, mold release agents, pigments, organic or inorganic fillers, neutralizing agents, lubricants, decomposition agents, metal deactivators, antifouling agents, antibacterial agents, Known additives such as other resins and thermoplastic elastomers can be listed.
The amount of these additives can be within a range that does not impair the effects of the present invention. For example, it is 0-50 weight part normally with respect to 100 weight part of polymers contained in alicyclic structure containing polymer resin, Preferably it is 0-30 weight part.

  In particular, when the alicyclic structure-containing polymer resin contains an ultraviolet absorber, it is preferable to use an ultraviolet absorber that absorbs ultraviolet rays other than the wavelength used in the step (A4). When the optical laminate as the product is required to absorb ultraviolet rays having a wavelength used in the step (A4), an ultraviolet absorber that absorbs ultraviolet rays having such a wavelength can be added to the adhesive layer. In such an embodiment, an optical laminate having an ultraviolet absorbing function in a wide wavelength range can be easily produced by using a combination of an ultraviolet absorber that absorbs different wavelengths in the substrate and the adhesive layer.

  The material constituting the substrate is preferably a material having high transparency. For example, it is preferable that the total light transmittance measured by using the material as a test piece having a thickness of 1 mm is usually 70% or more, preferably 80% or more, and more preferably 90% or more.

  The substrate film may be composed of a single layer or may be composed of a plurality of layers. When it is composed of a plurality of layers, the base film may be a laminate of a plurality of films with an adhesive or a pressure-sensitive adhesive, and a plurality of materials composed of different materials depending on a production method such as coextrusion. A layer may be formed. Further, the base film may be isotropic without undergoing an operation such as stretching, or may be provided with anisotropy by an operation such as stretching.

  The substrate may contain particles and have diffusibility. Specifically, for example, a material containing particles is used as the material of the substrate film described above to prepare a substrate containing particles, and this can be used in the present invention. When a base material contains particle | grains, the content rate of particle | grains can be 1-30 weight% with respect to a base material. As an example of the particle | grains which a base material can contain, the thing similar to the example of the particle | grains which an optical functional layer can contain later mentioned can be mentioned.

[Method for producing base film]
Although the manufacturing method of a base film is not specifically limited, For example, it can obtain by shape | molding the above-mentioned resin etc. with a well-known film forming method. Examples of the film forming method include a cast forming method, an extrusion forming method, and an inflation forming method. Among them, the melt extrusion method without using a solvent is preferable because the amount of residual volatile components can be efficiently reduced, the environmental load is low, the manufacturing operation is easy, and the manufacturing efficiency is high. Examples of the melt extrusion method include an inflation method using a die, and a method using a T die is preferable in terms of excellent productivity and thickness accuracy.

[Easily adhesive layer]
A base material can have an easily bonding layer in addition to a base film. An easily bonding layer can be provided so that it may be located in the surface of the front side and / or back side of a base material. When a base material has an easily bonding layer, the adhesiveness of a base material and an optical function layer and / or the adhesiveness of a base material and an adhesive layer can be improved. The easy adhesion layer is preferably provided in direct contact with the surface of the base film. The base material may further have functional layers such as an antistatic layer and a diffusibility-imparting layer between the base film and the easy adhesion layer.
As a material for forming the easy adhesion layer, a so-called water-based urethane resin can be preferably used. A water-based urethane resin is a composition which urethane resin contains in the state disperse | distributed to water-based media, such as water. An easy-adhesion layer containing a urethane resin can be formed by applying and curing such an aqueous urethane resin on a base film. The method for applying the water-based urethane resin on the base film is not particularly limited, and a known application method can be employed. Specific coating methods include wire bar coating, dipping, spraying, spin coating, roll coating, gravure coating, air knife coating, curtain coating, slide coating, and extrusion coating. Can be mentioned. The coating amount of the water-based urethane resin is not particularly limited, but the thickness after drying is preferably 0.01 to 5 μm, more preferably 0.02 to 2 μm, and particularly preferably 0.03 to 1 μm. Within the above range, sufficient adhesive strength between the substrate and the easy-adhesion layer can be obtained, and an optical laminate having no defects such as warping of the film can be provided. The method for curing the coating film of the water-based urethane resin is not particularly limited. For example, it can be cured by drying at a temperature of about 80 ° C. to 130 ° C. and volatilizing the water-based medium.

[Shape and physical properties of substrate]
Although the thickness of a base material is not specifically limited, The minimum can be 10 micrometers or more. Moreover, the upper limit can be 500 micrometers or less.

  The substrate is preferably a long film from the viewpoint of production efficiency. Here, the “long” means one having a length of at least 5 times the width, preferably 10 times or more, specifically in the form of a roll. It has a length that can be wound and stored or transported. The base film is made into a long film, and other layers such as an optical functional layer are continuously formed thereon to obtain a long multi-layered product (a). By obtaining a laminate and cutting it into a desired shape as required, efficient production can be performed.

  From the viewpoint of ease of carrying out the step (A4), the substrate is preferably one having a high ultraviolet transmittance. However, it is not necessary to have a high transmittance in a wide wavelength region of ultraviolet rays, and any substrate that has a high transmittance of ultraviolet rays having a wavelength suitable for use in the step (A4) can be preferably used. Specifically, the light transmittance used in the step (A4) is preferably 80% or more. More specifically, the transmittance of light having a wavelength of 365 nm is preferably 80% or more. More specifically, it is preferable to use a material having a transmittance of light of wavelength 365 nm of 80% or more and a transmittance of light of wavelength 300 nm of 20% or less.

[Material of optical functional layer: uncured resin]
In the present invention, an ultraviolet curable uncured resin is usually used as a material for forming the optical functional layer.
Although it does not specifically limit as uncured resin, The monomer (henceforth the monomer A) containing 1 or more isocyanate groups per molecule and 1 or more polymerizable unsaturated groups per molecule, and superposition | polymerization The composition (henceforth the composition Y) containing the monomer (henceforth the monomer B) which has 3 or more of unsaturated unsaturated groups per molecule and does not contain an isocyanate group can be used. By using the composition Y, the optical functional layer can have both high adhesion with the easy adhesion layer and high surface hardness.

  Examples of such polymerizable unsaturated groups include (meth) acryloyl groups and vinyl groups.

  Specific examples of the monomer A include (meth) acryloyl isocyanate, 2- (meth) acryloyloxyethyl isocyanate, 3- (meth) acryloyloxypropyl isocyanate, 2- (meth) acryloyloxy-1-methylethyl isocyanate, 2- (Meth) acryloyloxy-2-methylethyl isocyanate, 1,1-bis [(meth) acryloyloxymethyl] ethyl isocyanate, and m- (meth) acryloyloxyphenyl isocyanate. Among these, 2- (meth) acryloyloxyethyl isocyanate and 1,1-bis [(meth) acryloyloxymethyl] ethyl isocyanate are considered from the viewpoints of handleability, chemical stability, and industrial availability. Is preferred.

  Specific examples of the monomer B include glycerin tri (meth) acrylate, glycerin alkylene oxide tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, and trimethylolpropane polyalkylene oxide tri. (Meth) acrylate, trimethylolpropane tricaprolactonate tri (meth) acrylate, trimethylolethane tri (meth) acrylate, trimethylolethane polyalkylene oxide tri (meth) acrylate, trimethylolhexanetri (meth) acrylate, trimethylol Hexane polyalkylene oxide tri (meth) acrylate, trimethylol octane tri (meth) acrylate, trimethylol alcohol Tan polyalkylene oxide tri (meth) acrylate, pentaerythritol tri (meth) acrylate, trihydroxybenzene (such as pyrogallol) polyalkylene oxide adduct triacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol polyalkylene oxide tetra (meth) Acrylate, pentaerythritol tetracaprolactonate tetra (meth) acrylate, diglycerin tetra (meth) acrylate, diglycerin tri (meth) acrylate, diglycerin polyalkylene oxide tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate , Ditrimethylolpropane polyalkylene oxide tetra (meth) acrylate, isocyanuric acid O-modified tri (meth) acrylate, isocyanuric acid EO-modified tetra (meth) acrylate, ditrimethylolethane tetra (meth) acrylate, ditrimethylolethane polyalkylene oxide tetra (meth) acrylate, ditrimethylolbutanetetra (meth) acrylate, ditrimethylol Butane polyalkylene oxide tetra (meth) acrylate, ditrimethylol hexane tetra (meth) acrylate, ditrimethylol hexane polyalkylene oxide tetra (meth) acrylate, ditrimethylol octane tetra (meth) acrylate, ditrimethylol octane polyalkylene oxide tetra (meth) Acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( (Meth) acrylate, dipentaerythritol polyalkylene oxide penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol polyalkylene oxide hexa (meth) acrylate, dipentaerythritol hexacaprolactonate hexa (meth) acrylate , Tripentaerythritol hexa (meth) acrylate, tripentaerythritol hepta (meth) acrylate, tripentaerythritol octa (meth) acrylate, tripentaerythritol polyalkylene oxide hexa (meth) acrylate, tripentaerythritol polyalkylene oxide hepta (meth) Acrylate, tripentaerythritol polyalkylene oxide octa (meth) acrylate It can include various (meth) acrylate rates.

  In addition to the monomer A and the monomer B, the composition Y can contain any other monomer. Such optional monomers include a monomer having no isocyanate group and one polymerizable unsaturated group per molecule (hereinafter referred to as “monomer C”), and a monomer having no isocyanate group and having a polymerizable unsaturated group. Mention may be made of two monomers per molecule (hereinafter referred to as “monomer D”).

Specific examples of the monomer C include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, Benzyl (meth) acrylate, methoxyethyl (meth) acrylate, methoxyethoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) Acrylate, dipropylene glycol mono (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxyethoxyethyl (meth) acrylate, p-tert-butylphenol Enoxyethoxyethyl (meth) acrylate, p-nonylphenoxyethoxyethyl (meth) acrylate, octylphenoxyethoxyethyl (meth) acrylate, ethoxylated phenylphenol (meth) acrylate, ethoxylated O-phenylphenol (meth) acrylate, Phenoxypolyethylene glycol (meth) acrylate, 2- (meth) acryloyloxyethyl succinate, dodecylphenoxyethoxyethyl (meth) acrylate, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, tricyclo [5.2.1.0 ^{2 , 6]} decane mono-methylol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate of various (meth) acrylate diethylene glycol monovinyl Ether, 1,4-butanediol monovinyl ether, triethylene glycol monovinyl ether, hexaethylene glycol monovinyl ether, vinyl ethers such as 1,4-cyclohexanedimethanol monovinyl ether; N-vinylpyrrolidone, N-vinylformamide, N-acryloyl Mention may be made of N-vinylamide compounds such as morpholine.

Specific examples of monomer D include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene Glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, pentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, hydroxy Pivalyl hydroxypivalate di (meth) acrylate, hydroxypivalyl hydroxypivalate dicaprolactonate di (meth) acrylate, , 6-hexanediol di (meth) acrylate, tricyclodecane methanol di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, tricyclodecane dimethylol dicaprolactonate di (meth) acrylate, isocyanuric acid EO Modified di (meth) acrylate, 9,9-bis (4- (meth) acryloyloxyphenyl) fluorene, 9,9-bis (3-methyl-4- (meth) acryloyloxyphenyl) fluorene, 9,9-bis (3-methyl-4- (2- (meth) acryloyloxyethoxy) phenyl) fluorene, bisphenol A tetraethylene oxide adduct di (meth) acrylate, bisphenol A polyalkylene oxide adduct di (meth) acrylate, bisphenol F tet Ethylene oxide adduct di (meth) acrylate, bisphenol F polyalkylene oxide adduct di (meth) acrylate, bisphenol S tetraethylene oxide adduct di (meth) acrylate, bisphenol S polyalkylene oxide adduct di (meth) acrylate, water Addition bisphenol A tetraethylene oxide adduct di (meth) acrylate, water addition bisphenol A polyalkylene oxide adduct di (meth) acrylate, water addition bisphenol F tetraethylene oxide adduct di (meth) acrylate, water addition bisphenol F polyalkylene Oxide adduct di (meth) acrylate, water added bisphenol A di (meth) acrylate, water added bisphenol F di (meth) acrylate, dihydroxy base Zen (catechol, resorcin, hydroquinone, etc.) polyalkylene oxide di (meth) acrylate, alkyldihydroxybenzene polyalkylene oxide di (meth) acrylate, bisphenol A tetraethylene oxide adduct dicaprolactonate di (meth) acrylate, bisphenol F tetra Ethylene oxide adduct dicaprolactonate di (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decane dimethanol di (meth) acrylate, 1,4-cyclohexanedimethanol di (meth) acrylate, etc. Acrylates; fumaric acid esters such as diethyl fumarate, diisobutyl fumarate, di-n-butyl fumarate; diethylene glycol divinyl ether, 1,4-butanediol divinyl ether Le, triethylene glycol divinyl ether, hexaethylene glycol divinyl ether, may be mentioned vinyl ether such as 1,4-cyclohexane dimethanol divinyl ether.

  In composition Y, the content of isocyanate groups in the total amount of monomers (total of monomer A, monomer B, and other arbitrary monomers such as monomer C and monomer D) is 0.25 mmol / g or more, and monomer The ratio of the monomer B in the total amount is preferably 15% by weight or more. By containing the isocyanate group and the monomer B in such a ratio, the composition Y obtains an optical functional layer having high adhesion with an easy-adhesion layer based on isocyanate and high surface hardness based on crosslinking at a high level. Can do.

  In the composition Y, it is preferable that the acid value in the total amount of monomers is within a predetermined range. Specifically, the upper limit of the acid value is preferably 5 mgKOH / g or less, and more preferably 3 mgKOH / g or less. The acid value of all the monomers can be determined from the acid value of each monomer and the ratio of each monomer contained in all the monomers. By setting the acid value in such a low range, the storage stability of the composition Y is improved, and the production of the optical functional layer is facilitated. That is, since it is difficult to cause a change in properties such as an increase in viscosity from the preparation of the composition Y to the use, there is a limitation in the process that the preparation of the composition Y must be performed immediately before use. Less.

The composition Y can contain arbitrary components as needed in addition to the monomer A, the monomer B, and other arbitrary monomers (such as the monomer C and the monomer D). Specifically, a polymerization initiator, particles, a solvent, a matting agent, a slip agent, an antistatic agent, and a surfactant can be contained.
As a polymerization initiator, a thermal polymerization initiator and a photoinitiator can be illustrated. In particular, a photopolymerization initiator is preferable from the viewpoint of facilitating the step (A4). The photopolymerization initiator is a polymerization initiator that develops an action when exposed to light (that is, in response to light irradiation). Here, the light for polymerization is not only visible light but also ultraviolet light, infrared light, However, from the viewpoint of imparting ultraviolet curability to the composition Y, the photopolymerization initiator is preferably an initiator that exhibits an action by ultraviolet rays. Moreover, it is preferable that a polymerization initiator is a radical polymerization initiator.

  Specific examples of the radical polymerization initiator sensitive to visible light or ultraviolet light include acetophenone, 2,2-dimethoxy-2-phenylacetophenone, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, 1,2-benzyl-2-methylamino-1- (4-morpholinophenyl) butanone, 1,2-hydroxy-2-methyl-1-phenylpropane Acetophenone or derivatives thereof such as -1-one; benzophenone or derivatives thereof such as benzophenone, 4,4′-bis (dimethylamino) benzophenone, 4-trimethylsilylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide; benzoin, benzoin Echi Benzoin such as ether, benzoin propyl ether, benzoin isobutyl ether, benzoin isopropyl ether or derivatives thereof; methylphenylglyoxylate, benzoin dimethyl ketal, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dichloro) Benzoyl) -phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-ethoxyphenylphosphine oxide, bis (2,6 -Dichlorobenzoyl) -4-biphenylylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) 2-naphthylphosphine oxide, bis (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-chlorophenylphosphine oxide, bis (2,6-dichloro) Benzoyl) -2,4-dimethoxyphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -decylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-octylphenylphosphine oxide, bis (2,6 -Dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -phenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -2,5-dimethylphenylphosphine oxide Bis (2,6-dichloro) -3,4,5-trimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6-dichloro-3,4,5-trimethoxybenzoyl) -4-ethoxyphenylphosphine oxide, bis (2 -Methyl-1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-phenylphosphine oxide, bis (2-methyl-1-naphthoyl) -4-biphenyl Rylphosphine oxide, bis (2-methyl-1-naphthoyl) -4-ethoxybiphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -2-naphthylphosphine oxide, bis (2-methyl-1-naphthoyl)- 4-propylphenylphosphine oxide, bis (2-methoxyl 1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2-methyoxy-1-naphthoyl) -4-methoxyphenylphosphine oxide, bis (2-methyoxy-1-naphthoyl) -4-biphenylylphosphine oxide, Bis (2-chloro-1-naphthoyl) -2,5-dimethylphenylylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,6-trimethylpentylphosphine oxide, bis (2,4,6- And trimethylbenzoyl) -phenylphosphine oxide.

  The optical functional layer preferably contains particles. In order to obtain such a preferable optical functional layer, the composition Y can contain particles. When the optical functional layer contains particles, the light is diffused in the optical functional layer, thereby increasing the extraction efficiency.

  The particles may be transparent or opaque. As the material for the particles, metals, metal compounds, resins, and the like can be used. Examples of the metal compound include metal oxides and nitrides. Specific examples of metals and metal compounds include metals having high reflectivity such as silver and aluminum, and metal compounds such as silicon oxide, aluminum oxide, zirconium oxide, silicon nitride, tin-doped indium oxide, and titanium oxide. Can do. On the other hand, examples of the resin include methacrylic resin, polyurethane resin, and silicone resin. In particular, a silicone resin is particularly preferable from the viewpoints of dispersibility and wet heat resistance. In addition, the particle | grain material may be used individually by 1 type, and may be used combining two or more types by arbitrary ratios.

The shape of the particles can be a spherical shape, a cylindrical shape, a cubic shape, a rectangular parallelepiped shape, a pyramid shape, a conical shape, a star shape, or the like.
The particle diameter of the particles is preferably 0.1 μm or more and 10 μm or less, more preferably 5 μm or less, and still more preferably 1 μm or less. Here, the particle diameter is a 50% particle diameter in an integrated distribution obtained by integrating the volume-based particle amount with the particle diameter as the horizontal axis. The larger the particle size, the larger the content ratio of particles necessary for obtaining the desired effect, and the smaller the particle size, the smaller the content. Therefore, as the particle size is smaller, desired effects such as a reduction in change in color depending on the observation angle and an improvement in light extraction efficiency can be obtained with fewer particles. When the particle shape is other than spherical, the diameter of the sphere having the same volume is used as the particle size.

  When the particles are transparent particles and the particles are contained in the resin, the difference between the refractive index of the particles and the refractive index of the resin is preferably 0.05 to 0.5. More preferably, it is 07-0.5. Here, either the particle or the refractive index of the resin may be larger. If the refractive index of the particle and the resin is too close, the diffusion effect cannot be obtained and the color unevenness is not suppressed. Conversely, if the difference is too large, the diffusion increases and the color unevenness is suppressed, but the light extraction effect is reduced. become.

  It is preferable that the content rate of the particle | grains in the composition Y is 3 to 50 weight% as a ratio of the particle | grains in the sum total of particle | grains and a monomer total amount.

  Examples of the solvent that can be contained in the composition Y include methyl ethyl ketone, ethyl acetate, butyl acetate, cyclohexane, and cyclohexanone. However, for the convenience of forming the optical functional layer, it is preferable that the composition Y is prepared without adding a solvent and does not require a process for volatilizing the solvent during curing.

The preparation method of the composition Y is not specifically limited, For example, it can obtain by mixing the said component.
Although the property of the composition Y is not specifically limited, It is preferable that the viscosity is a range suitable for operations, such as liquid feeding, application | coating, hardening after application | coating. Specifically, the lower limit of the viscosity is preferably 5 cP or more, and more preferably 30 cP or more. On the other hand, the upper limit of the viscosity is preferably 500 cP or less, and more preferably 100 cP or less.

[Shape and properties of optical functional layer]
Then, the optical function layer in the optical laminated body manufactured by the manufacturing method of this invention is demonstrated. The haze of the optical functional layer can be 0% to 95% depending on the demand for the film. When the haze of the optical functional layer is 0% to 20%, both the extraction efficiency and the front luminance can be increased. When the haze of the optical functional layer is 75% to 95%, both the light extraction efficiency and the change in color depending on the observation angle can be reduced. The haze can be adjusted, for example, by appropriately adjusting the content ratio of the particles described above.

The optical functional layer preferably has a concavo-convex structure provided by a mold having a concavo-convex structure in the step (A3). By having such a concavo-convex structure, good extraction efficiency can be achieved when the optical laminate of the present invention is used as a member provided on a light extraction surface of an optical device such as a display device or a light source device.
Specifically, the concavo-convex structure can preferably include a concavo-convex structure including a plurality of concave portions including slopes and flat portions located around the concave portions. Here, the “slope” is a surface that forms an angle that is not parallel to the surface direction of the substrate. On the other hand, the surface on the flat portion can be a surface parallel to the surface direction of the substrate.

  Such an uneven structure will be described in more detail with reference to FIGS. FIG. 8 is a partial top view schematically showing an enlarged structure of the surface 10U of the optical functional layer 111 shown in FIGS. FIG. 9 is a partial cross-sectional view showing a cross section of the optical functional layer 111 taken along a plane that passes through the line 10a of FIG. 8 and is perpendicular to the main surface of the optical laminate.

  Each of the plurality of recesses 113 is a depression having a regular quadrangular pyramid shape. Therefore, the slopes 11A to 11D of the recess 113 have the same shape, and the bases 11E to 11H form a square. The line 10a is a line that passes over all the vertices 11P of the recesses 113 in a row, and is a line parallel to the bottom sides 11E and 11G of the recesses 113.

  The recess 113 is continuously arranged in two orthogonal arrangement directions at a constant interval. One of the two arrangement directions X is parallel to the bases 11E and 11G. In this direction X, the plurality of recesses 113 are aligned at a constant interval 11J. The other direction Y of the two arrangement directions is parallel to 11F and 11H. In this direction Y, the plurality of recesses 113 are aligned at a constant interval 11K.

  The angles formed by the inclined surfaces 11A to 11D constituting each of the recesses 113 with the flat portion 114 (for the inclined surfaces 11B and 11D, the angles 11L and 11M shown in FIG. 9 respectively) are set to 60 °, for example. The apex angle of the regular quadrangular pyramid, that is, the angle formed by the opposed slopes at the apex 11P (the angle 11N shown in FIG. 9 for the angles formed by the slopes 11B and 11D) is also 60 °.

  Thus, the optical functional layer of the optical layered body has a configuration including a plurality of concave portions and a flat portion positioned around each concave portion, so that the surface corresponds to the device light exit surface of the surface light source device. In this case, the light extraction efficiency can be increased, the change in color depending on the observation angle can be reduced, and the occurrence of chipping of the concavo-convex structure due to external impact can be prevented, and the mechanical strength of the light exit surface of the device can be reduced. Can be improved.

  When the optical laminate includes the optical functional layer having the above-described uneven structure, the displacement of at least one of the x coordinate and the y coordinate of the chromaticity coordinate in all hemispherical directions in the light emitted from the optical functional layer side is This can be reduced as compared with the case where the above configuration is not adopted. For this reason, in the surface light source device of this invention, when an optical laminated body is provided with the optical function layer which has an uneven structure, the change of the color by an observation angle can be suppressed. As a method of measuring the displacement of chromaticity in all hemispherical directions, for example, the spectral radiance on the normal direction of the device light exit surface (that is, the direction perpendicular to the device light exit surface macroscopically ignoring the concave portion). When a meter is installed and the normal direction is set to 0 °, a chromaticity coordinate can be calculated from the emission spectrum measured in each direction by providing a mechanism that can rotate the light exit surface of the device from -90 to 90 °. The displacement can be calculated.

  When the concavo-convex structure is observed from the direction perpendicular to the optical layered body, the ratio of the area occupied by the flat portion to the total of the area occupied by the flat portion and the area occupied by the concave portion (hereinafter referred to as “flat portion ratio”). The light extraction efficiency of the surface light source device can be improved by appropriately adjusting. Specifically, by setting the flat portion ratio to 10 to 75%, good light extraction efficiency can be obtained, and the mechanical strength of the device light exit surface can be increased.

  In the concavo-convex structure, the concave portion may have, for example, a cone shape, a partial spherical shape, a groove shape, and a combination thereof in addition to the pyramid shape described above. The pyramid shape may be a quadrangular pyramid having a square bottom surface as exemplified by the recess 113, but is not limited thereto, and may be a pyramid shape such as a triangular pyramid, a pentagonal pyramid, a hexagonal pyramid, or a quadrangular pyramid having a non-square base. You can also. Furthermore, the cones and pyramids mentioned in this application include not only ordinary cones and pyramids with sharp points, but also rounded tips or flat chamfered shapes (frustum-shaped shapes, etc.). Yes.

  The depth of the concave portion in the concavo-convex structure is not particularly limited, but the maximum centerline average roughness measured on the surface on which the concavo-convex structure is formed in various directions (various directions in a plane parallel to the light exit surface). The value (Ra (max)) can be in the range of 1 to 50 μm. Moreover, the preferable depth of a recessed part can be defined relatively with respect to the thickness of an optical function layer. For example, when a hard material that is advantageous for maintaining the durability of the concavo-convex structure is used as the material of the optical functional layer, it is possible to increase the flexibility of the optical laminate by reducing the thickness of the optical functional layer. Thus, handling of the optical laminate in the manufacturing process of the surface light source device is facilitated. Specifically, the ratio of the thickness 16E of the optical functional layer 111 to the depth 16D of the recess shown in FIG. 9 is preferably 1: 1 to 1: 3.

  The lower limit of the thickness of the optical functional layer is preferably 1 μm or more, more preferably 5 μm or more, while the upper limit thereof is preferably 50 μm or less, more preferably 25 μm or less, and 15 μm. Even more preferably: In particular, when the thickness is equal to or less than the above upper limit, it is possible to prevent deformation such as curling of the optical laminate due to curing shrinkage, and to obtain a laminate having a good shape.

  In the present invention, the angle formed by the inclined surface of the recess and the light exit surface is preferably 40 to 70 °, and more preferably 45 to 60 °. For example, when the shape of the recess is a quadrangular pyramid, the apex angle (corner 11P in FIG. 9) is preferably 60 to 90 °. Further, from the viewpoint of improving light extraction efficiency while minimizing the change in color depending on the observation angle, it is preferable that the angle formed by the inclined surface and the surface of the base material is large, and specifically, for example, 55 ° or more. Is preferable, and it is still more preferable to set it as 60 degrees or more. In this case, the upper limit of the angle can be about 70 ° in consideration of maintaining the durability of the optical function layer.

  In the concavo-convex structure, the plurality of concave portions can be arranged in any manner. For example, a plurality of recesses can be arranged along two or more directions on the surface. More specifically, they can be arranged along two orthogonal directions like the recesses 113 shown in FIGS.

  In the case where the concave portions are arranged in two or more directions, a gap between adjacent concave portions is provided in one or more directions among them, and the flat portion can be constituted by the gap. For example, in the arrangement of the recesses 113 shown in FIG. 8, gaps with intervals 11J and 11K are provided in two orthogonal directions, and the flat part 114 is configured by the gaps. By adopting such a configuration, it is possible to achieve both good light extraction efficiency and mechanical strength of the laminate surface.

[Adhesive layer]
The adhesive for forming the adhesive layer is not only a narrowly defined adhesive (a so-called hot melt type adhesive having a shear storage modulus of 1 to 500 MPa at 23 ° C. and not exhibiting tackiness at room temperature), A pressure-sensitive adhesive having a shear storage modulus at 23 ° C. of less than 1 MPa is also included. Specifically, in the surface light source device obtained when the optical laminate obtained by the manufacturing method of the present invention is applied to the manufacture of the surface light source device, adjacent layers (base material and substrate of the surface light source device, for example) It is possible to appropriately use a material having a near refractive index, an ultraviolet absorbing function, and capable of transmitting at least a part of visible light. More specifically, an acrylic adhesive (including a pressure-sensitive adhesive) is used.
The adhesive can contain an ultraviolet absorber. By containing a UV absorber, an adhesive layer having a good UV absorbing function can be obtained. As the ultraviolet absorber, benzophenone series, salicylate series, benzoxazine series, benzotriazole series, hydroxyphenyltriazine series, azomethine series, indole series, zinc oxide series, cerium oxide series titanium oxide series can be used. Moreover, a hindered amine light stabilizer can also be used together as needed. As for the content rate of the ultraviolet absorber in 100 weight% of contact bonding layers, it is preferable that a minimum is 0.05 weight% or more, and it is more preferable that it is 0.1 weight% or more. On the other hand, the upper limit is preferably 10% by weight or less, and more preferably 5% by weight or less. The amount of the ultraviolet absorber can be appropriately adjusted according to the thickness of the adhesive layer.

  The thickness of the adhesive layer is preferably 5 μm to 100 μm. The light transmittance at each wavelength of the adhesive layer is preferably 5% or less at 290 nm to 360 nm and 40% or less at 360 nm to 380 nm.

  The adhesive layer may contain particles and have diffusibility. Specifically, for example, an adhesive containing particles is used as an adhesive for forming the adhesive layer described above, and this can be used in the present invention. When the adhesive layer contains particles, the content ratio of the particles can be 1 to 30% by weight with respect to the adhesive layer. As an example of the particle | grains which an adhesive layer can contain, the thing similar to the example of the particle | grains which an optical functional layer mentioned above can contain can be mentioned.

  In the production method of the present invention, it is preferable that any of the base material, the optical function layer, and the adhesive layer contains particles imparting light diffusibility. By including such particles, the light extraction efficiency can be further improved. In the case of performing the 2P method, when irradiation with ultraviolet rays is performed through a layer containing such particles, the ultraviolet rays are prevented from reaching the layer to be cured, and the resin is hardly cured. This becomes a serious problem particularly when an optical laminate having an ultraviolet absorbing function is produced. In the production method of the present invention, since ultraviolet irradiation can be performed efficiently, even when each layer particle is contained, production by the 2P method can be performed efficiently.

  The preferred range of the content ratio of the particles in each of the substrate, the optical functional layer, and the adhesive layer is as described above, but the content ratio of the particles in the entire base material, the optical functional layer, and the adhesive layer is The haze value can be 85 to 99%.

〔separator〕
As a separator used for a process (B), the separator film which consists of materials, such as polyester, a polypropylene, polyethylene, can be used. Or what consists of a separator film and other arbitrary layers can also be used. Examples of such optional layers include layers such as a release treatment layer and an antistatic layer.

[Surface light source device]
The optical layered body of the present invention obtained by the manufacturing method of the present invention can be used for manufacturing various display devices, light source devices, lighting devices and the like. In particular, it can be used for manufacturing the surface light source device of the present invention described below.
The surface light source device of the present invention is a surface light source device including an organic EL element, and is formed on the light output surface side of the organic EL element by using the optical layered body of the present invention. And an adhesive layer.
Specifically, when the optical layered body of the present invention does not contain a separator, the separator is peeled off if it is included, and a multi-layered product including an optical functional layer, a base material, and an adhesive layer in this order is provided. By pasting on the surface, the surface light source device of the present invention can be obtained.

[Specific example of surface light source device]
FIG. 10 is a perspective view schematically showing an example of the surface light source device of the present invention. FIG. 11 shows the surface light source device 10 shown in FIG. 10 through the line 1a-1b in FIG. It is sectional drawing which shows the cross section cut | disconnected by the surface perpendicular | vertical to a surface direction. The surface light source device 10 is provided with a separator 141 peeled from the optical laminate 100 shown in FIGS. 1 and 2, that is, a multi-layered product including an optical functional layer 111, a substrate 121, and an adhesive layer 131.

  The surface light source device 10 is a device having a rectangular flat plate structure. The surface light source device 10 includes an organic EL element substrate 151, a transparent electrode layer 161 provided in contact with one surface 156 of the organic EL element substrate 151, and a light emitting layer 162 provided in contact with the transparent electrode layer 161. And a reflective electrode layer 163 provided in contact with the light emitting layer 162. The transparent electrode layer 161, the light emitting layer 162 and the reflective electrode layer 163 constitute the organic EL element 160. The surface light source device 10 further includes a sealing substrate 171 as an optional component on the surface 165 side of the organic EL element 160 opposite to the device light exit surface.

  The surface light source device 10 further includes a multilayer including the adhesive layer 131, the base material 121, and the optical function layer 111 on the other surface 157 of the organic EL element substrate 151.

  Light from the light emitting layer 162 passes through the transparent electrode layer 161 or is reflected by the reflective electrode layer 163, passes through the light emitting layer 162 and the transparent electrode layer 161, and travels toward the device output surface side. Most of the light emitted from the organic EL element 160 is transmitted through the organic EL element substrate 151, the adhesive layer 131, the base material 121, and the optical functional layer 111 in this order, and is emitted from the surface 10U. Therefore, the surface 10U of the optical functional layer 111 becomes the device light exit surface of the surface light source device 10.

  As described above, the light from the light emitting layer 162 is transmitted through the optical function layer 111 and emitted, whereby the light extraction efficiency can be improved by the uneven structure of the surface 10U of the optical function layer 111. Further, when the layers such as the adhesive layer 131, the base material 121, and the optical functional layer 111 have diffusibility, the light is emitted in a state where the light is further diffused thereby. Change can be suppressed.

  Moreover, when the base material 121 consists of alicyclic structure containing polymer resin, the component which degrades the light emitting layer in external air, such as water vapor | steam and oxygen, is prevented from reaching the light emitting layer from the device light-emitting surface side. Therefore, it can be set as an apparatus with a long lifetime.

[Organic EL element of surface light source device]
As exemplified as the organic EL element 160, the surface light source device of the present invention includes an organic EL element, and the organic EL element includes a transparent electrode layer, an electrode layer facing the transparent electrode layer such as a reflective electrode layer, and the like. The light-emitting layer is provided between these electrode layers and emits light when a voltage is applied from the electrodes.

  In the organic EL element, a layer such as an electrode or a light emitting layer constituting the element is formed on a substrate, a sealing member that covers those layers is further provided, and the layer such as the light emitting layer is sealed with the substrate and the sealing member. Generally, it is configured. Usually, the element that emits light from the substrate side here is called a bottom emission type, and the element that emits light from the sealing member side is called a top emission type. Any of these may be sufficient as the surface light source device of this invention.

  In this invention, it does not specifically limit as a light emitting layer which comprises an organic EL element, A well-known thing can be selected suitably. The light-emitting material in the light-emitting layer is not limited to one type, and the light-emitting layer is not limited to one layer, and may be a single layer or a combination of a plurality of layers in order to suit the use as a light source. Thereby, light of white or a color close thereto can be emitted.

  The organic EL device may further include 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 in addition to the light emitting layer between the electrodes. The organic EL element can further include arbitrary components such as a wiring for energizing the electrode and a peripheral structure for sealing the light emitting layer.

  The electrode facing the transparent electrode layer in the optical laminate of the organic EL element is not particularly limited, and a known one can be appropriately selected. Like the organic EL element 160 shown in FIGS. 10 and 11, an organic EL element that emits light toward the optical functional layer 111 can be obtained by using the electrode 163 facing the transparent electrode layer 161 as a reflective electrode. Moreover, both electrodes can be transparent electrodes, and further by having a reflecting member at a position farther from the light-emitting surface than the transparent electrode far from the light-emitting surface, it is possible to achieve light output to the light-emitting surface side.

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 material for the green light emitting layer include pyrazoline 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.
As a material for the red light emitting layer, a europium complex or the like can be used.
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.

[Application of surface light source device]
The surface light source device of the present invention can be used as a light source device such as a lighting fixture and a backlight device.
The luminaire includes the surface light source device of the present invention as a light source, and can further include arbitrary components such as a member for holding the light source and a circuit for supplying power. The backlight device includes the surface light source device of the present invention as a light source, and further includes a housing, a circuit for supplying electric power, a diffusion plate for making light emitted more uniform, a diffusion sheet, a prism sheet, and the like. The components can be included. The use of the backlight device can be used as a backlight of a display device such as a liquid crystal display device that displays an image by controlling pixels and a display device that displays a fixed image such as a signboard.

[Others]
The present invention is not limited to the above specific examples, and can be arbitrarily modified within the scope of the claims of the present application and equivalents thereof.
For example, the optical layered body of the present invention may further include an arbitrary layer in addition to the above-described layers. Such an optional layer may be, for example, a coating layer further provided on the concavo-convex structure on the surface of the optical functional layer, and the coating layer defines the concavo-convex structure on the device light exit surface of the surface light source device of the present invention. You may do.
Moreover, in the illustration of the above embodiment, the concave portions distributed over the entire surface of the optical functional layer are shown as those having only the same shape distributed. However, in the concave-convex structure, concave portions having different shapes are mixed. You may do it. For example, pyramid-shaped recesses of different sizes are mixed, pyramid-shaped recesses and cone-shaped recesses are mixed, or a combination of multiple pyramids and a simple pyramid shape are mixed. It may be.
Further, in the above specific example, the width of the flat portion constituting the concavo-convex structure and the interval between the adjacent flat portions are always constant, but the width of the flat portion is narrow and wide. Moreover, the location where the space | interval of a flat part is narrow and the wide location may be mixed. In such a manner, rainbow unevenness due to interference is suppressed by adopting an aspect in which one or more elements of the height, width, and interval of the flat portion are provided with a dimensional difference exceeding the difference that causes interference of emitted light. can do.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In the following examples, “parts” and “%” representing the quantity ratio of materials represent weight ratios unless otherwise specified.

<Example 1>
(1-1. Preparation of substrate)
Pellets of thermoplastic norbornene resin (Tg 143 ° C., weight average molecular weight 375,000) were dried at 100 ° C. for 4 hours using a hot air dryer and then supplied to the extruder. The film was extruded from a T-die at a molten resin temperature of 230 ° C. and wound up at a take-up speed of 18.0 m / min to obtain a film 1 having a width of 400 mm and a length of 250 m.

One surface of the obtained film 1 was subjected to corona treatment at a discharge amount of 500 W · min / m ² using a corona discharge treatment apparatus (Kasuga Denki Co., Ltd.).
20 parts of an aqueous urethane resin (Superflex 210, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 1 part of a crosslinking agent (adipic acid dihydrazide, manufactured by Wako Pure Chemical Industries, Ltd.) A coating solution for forming an easy-adhesion layer comprising 5 parts, 4 parts of silica particles (Snowtech XL, manufactured by Nissan Chemical Industries) and 80 parts of pure water was prepared.
The coating solution is applied to the corona-treated surface of film 1 using a gravure coater so that the dry film thickness is 0.1 μm, and dried at 95 ° C. to form an easy-adhesion layer. -The base material 1 which has the layer structure of (film 1) was obtained. The base material 1 was wound up in a roll shape.
When the obtained base material 1 was measured with the spectrophotometer (made by V-570JASCO), the transmittance | permeability in wavelength 365nm was 91%.

(1-2. Preparation of transfer roll)
Cylindrical transfer roll having a diameter of 300 mm and a length of 400 mm having a shape in which regular quadrangular pyramids having an apex angle of 60 ° and a base of 25 μm are arranged at a pitch of 30 μm (that is, a flat portion of 5 μm exists between adjacent quadrangular pyramids). Was prepared.

(1-3. Step (A1): Formation of Uncured Resin Layer)
2-methacryloyloxyethyl isocyanate 3 parts, trimethylolpropane triacrylate 50 parts, ethoxylated phenyl acrylate 47 parts, silicone particles (Tospearl 110, average particle size 2.0 μm, manufactured by Momentive Materials), and photoinitiator ( 3 parts (Irgacure 184, manufactured by Ciba Specialty Chemicals) were mixed to prepare an ultraviolet curable coating solution.

  The base material 1 obtained in (1-1) is fed out at a conveyance speed of 10 m / min, and an ultraviolet curable coating solution is applied to the surface of the easy-adhesion layer with a coating film thickness of 15 μm using a die coater. Then, an uncured resin layer was formed to obtain a multilayer having a layer structure of (uncured resin layer) − (adhesive layer) − (film 1).

(1-4. Steps (A2) to (A4): Transfer, curing, and peeling of uneven structure)
The multilayer obtained in (1-3) was pressed against a transfer roll and nipped with a rubber roll having a diameter of 100 mm. At this time, the multilayer was passed so that the uncured resin layer was in contact with the transfer roll and the film 1 was in contact with the rubber roll.
While the transfer roll was in contact with the uncured resin layer, the surface of the multilayer film 1 side was irradiated with ultraviolet rays with an integrated light amount of 1500 mJ / cm ² using a D bulb (manufactured by Fusion). Thereby, ultraviolet rays permeate | transmit the film 1 and an easily bonding layer, and reach | attain the layer of uncured resin, the layer of uncured resin hardens | cures, an optical function layer is formed, (optical function layer)-(easy adhesion layer) )-(Film 1) was obtained. The multilayer (a) was wound into a roll. When the surface of the multilayer (a) was observed with a microscope, it was confirmed that the optical functional layer had an uneven shape transferred from the transfer roll surface.

(1-5. Step (B): Formation of Adhesive Layer)
100 parts of acrylic polyester copolymer (Cybinol AT352, made by Seiden Chemical Co., Ltd.), 30 parts by weight of ethyl acetate, 10 parts by weight of toluene, 0.05 part of hexamethylene diisocyanate (made by Nippon Polyurethane Co., Ltd.), and UV absorber (TINUVIN109 1.5 parts of a benzotriazole compound manufactured by Tea Chemical Co., Ltd.) were mixed to prepare a coating solution for forming an adhesive layer.
As a separator, a 25 μm thick polyester separator film (Panapeel PET25 TP-01 manufactured by Panac Co., Ltd.) was prepared. The separator is fed out from the feed roll under conditions of 10 m / min, and the coating solution is applied on one surface of the separator so that the dry film thickness becomes 35 μm, and then dried in an oven at 90 ° C. (adhesive layer) − A multilayer (b) having a layer structure of (separator) was obtained.

(1-6. Step (C): Affixing the multilayer (a) and the multilayer (b))
Using the corona discharge treatment apparatus (manufactured by Kasuga Denki Co., Ltd.) on the surface of the multilayer (a) obtained in (1-4) on the film 1 side, the discharge amount is 500 W · min / m ^2. Was given. This surface is brought into contact with the surface on the adhesive layer side of the multilayer (b) obtained in (1-5) and squeezed with a nip roll, and (optical function layer)-(adhesive layer)-(film 1) An optical laminate 1 having a layer configuration of-(adhesive layer)-(separator) was obtained. The obtained optical laminated body 1 was wound up in roll shape.

(1-7. Production of surface light source device 1)
On one surface of a 0.7 mm thick glass substrate, transparent electrode layer 100 nm, hole transport layer 10 nm, yellow light emitting layer 20 nm, blue light emitting layer 15 nm, electron transport layer 15 nm, electron injection layer 1 nm, and reflective electrode layer 100 nm, They were formed in this order. The hole transport layer to the electron transport layer were all made of an organic material. The yellow light emitting layer and the blue light emitting layer 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 at 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 from the hole injection layer to the reflective electrode layer is carried out by placing a glass substrate on which a transparent electrode layer has already been formed in a vacuum evaporation apparatus, and successively using the resistance heating method for the materials from the hole transport layer to the reflective electrode layer. This was done by vapor deposition. 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 further, the hole transport layer to the reflective electrode layer were sealed with a sealing member, and the organic EL light emitting device 1 was produced.

  The separator of the optical laminate obtained in (1-6) was peeled off to expose the adhesive layer. The exposed adhesive layer was attached to the glass surface on the light exit surface side of the organic EL light emitting device 1 to obtain the surface light source device 1.

<Example 2>
(2-1. Production of optical laminate 2)
Other than changing the following points, the same as (1-2) to (1-6) of Example 1, (optical function layer)-(base material 2)-(adhesive layer)-(separator) An optical layered body 2 having a layer structure was obtained.
-It replaced with the base material 1 and the base material 2 (Double-sided easily-adhesive polyester film, Lumirror U34, thickness 100 micrometers, transmittance | permeability 87% of wavelength 365nm, Toray Industries, Inc. make) was used.
-In place of TINUVIN109, BONASORB UA-3912 (manufactured by Orient Chemical Industries, Inc., an indole compound) was used as an ultraviolet absorber.
-The corona discharge process of the process (1-6) was abbreviate | omitted.

(2-2. Manufacture of surface light source device 2)
A surface light source device 2 was obtained in the same manner as in Example 1 (1-7) except that the optical laminate 2 was used in place of the optical laminate 1.

<Comparative Example 1>
(C1-1. Production of substrate-separator multilayer)
A multilayer (b) was obtained in the same manner as in Example 1 (1-5). The surface on the adhesive layer side of the obtained multilayer (b) and one surface of the base material 2 (same as used in Example 2) were bonded together and squeezed with a nip roll, (base material 2) A multilayer having a layer structure of-(adhesive layer)-(separator) was obtained. The resulting multilayer was wound up in a roll.
It was 8% when the transmittance | permeability in wavelength 365nm of the obtained multilayer was measured with the spectrophotometer (V-570, JASCO company make).

(C1-2. Formation of uncured resin layer)
The multilayer product obtained in (C1-1) is fed out at a conveyance speed of 10 m / min, and the same UV curable coating as that used in (1-3) of Example 1 is applied to the surface of the substrate 2 side. Using a die coater, the liquid is applied at a coating film thickness of 15 μm to form an uncured resin layer, (uncured resin layer) − (base material 2) − (adhesive layer) − (separator) layer A multilayer having a configuration was obtained.

(C1-3. Transfer, curing and peeling of concavo-convex structure)
In the same manner as in (1-4) of Example 1 except that the multilayer material obtained in (C1-2) was used instead of the multilayer material obtained in (1-3), (Optical) The optical laminated body 3 which has the layer structure of (functional layer)-(base material 2)-(adhesion layer)-(separator) was obtained.
The obtained optical layered body 3 has a tack feeling on the surface, and the curing of the uncured resin layer is extremely insufficient. Therefore, the production of the optical layered body by such a method may be inferior in productivity. all right.

<Comparative example 2>
In (1-5), the optical layered body 4 was prepared in the same manner as in (1-1) to (1-6) of Example 1 except that no ultraviolet absorber was added to the coating liquid for forming the adhesive layer. Got.
A surface light source device 4 was obtained in the same manner as in Example 1 (1-7) except that the optical laminate 4 was used in place of the optical laminate 1.

<Evaluation of surface light source device>
With respect to the surface light source devices 1, 2, and 4 obtained in Example 1, Example 2, and Comparative Example 2, the degree of deterioration of the light emitting element caused by irradiating the light exit surface with light was evaluated.
A direct current voltage of 5 V was applied to the surface light source device to emit light, and the luminance in the front direction from the outgoing surface was measured using a luminance meter (MCPD-7000, manufactured by Otsuka Electronics Co., Ltd.). Then, the light from the xenon lamp was irradiated to the light emission surface of the surface light-emitting device at 6 mW / cm ² (wavelength 405 nm) for 7 hours. After the irradiation, the luminance was measured in the same procedure as the luminance measurement before the irradiation.
In the surface light source devices 1 and 2, the luminance after irradiation decreased by 10% and 8%, respectively, compared with the luminance before irradiation. In the surface light source device 4, the luminance after irradiation was reduced by 40% compared to the luminance before irradiation. Thus, it was confirmed that the optical degradation of the organic EL element can be suppressed when an optical layered body containing an ultraviolet absorber is used.

DESCRIPTION OF SYMBOLS 10: Surface light source device 10U: Optical functional layer surface 11A-11D: Slope 11E-11H: Bottom of recessed part 100: Optical laminated body 111: Optical functional layer which has an uneven structure 113: Recessed part 114: Flat part 121: Optical laminated body base material 131: Adhesive layer 141: Separator 151: Organic EL element substrate 160: Organic EL element 161: Transparent electrode layer 162: Light emitting layer 163: Reflective electrode layer 171: Sealing substrate

Claims (4)

It is a base material including a base film and an easy-adhesion layer having a thickness of 0.01 to 5 μm, and the easy-adhesion layer is located on the front side of the base material or on both the front side and the back side of the base material. A base material provided to be
An optical functional layer provided on the front surface of the substrate;
An adhesive layer having an ultraviolet absorbing function provided on the back surface of the base material, and a separator provided on the opposite side of the adhesive layer from the base material,
At least one of the base material, the optical functional layer, and the adhesive layer is a method for producing an optical laminate including particles that impart light diffusibility,
A step (A) of forming the optical functional layer on the surface of the substrate and obtaining a multilayer (a) having the substrate and the optical functional layer;
(B) forming an adhesive layer having the ultraviolet absorption function on the separator, and obtaining a multilayer (b) having the separator and the adhesive layer;
The multilayer product (a) and said multilayer product (b) and a bonded, seen including a step (C) to the back surface providing the adhesive layer of the double layer thereof (a),
The step (A)
A step (A1) of applying an ultraviolet curable uncured resin to the surface of the base material to form a layer of the uncured resin;
A step (A3) of bringing a mold having an uneven structure into contact with the uncured resin layer;
Irradiating ultraviolet rays from the back side of the base material to cure the uncured resin layer and obtaining an optical functional layer made of the cured resin (A4);
A step (A5) of peeling the mold from the optical functional layer;
Including
The adhesive layer contains an ultraviolet absorber in a content ratio of 0.05 wt% or more and 10 wt% or less.
Manufacturing method of optical laminated body. It is a manufacturing method of the optical layered product according to claim 1 ,
The manufacturing method of the optical laminated body which further includes the process (A2) of heating the layer of the said non-hardened resin after completion | finish of the said process (A1) and before the start of the said process (A4). It is a manufacturing method of the optical layered product according to claim 1 or 2 ,
The manufacturing method of the optical laminated body whose transmittance | permeability of the light of wavelength 365nm of the said base material is 80% or more. It is a manufacturing method of the optical layered product according to any one of claims 1 to 3 ,
The manufacturing method of the optical laminated body in which the said base material contains the film which consists of alicyclic structure containing polymer resin whose weight average molecular weight is 35,000 or more.

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