TW201351404A - Production method for multilayer optical recording medium - Google Patents

Abstract

This invention provides a production method for multilayer optical recording medium (20) capable of reducing the likelihood of warpage. The method is to produce a laminated structure body (14), in which several unit laminated bodies (11), each including an adhesive layer (2) and an optical recording layer (1), are laminated on one side of the substrate (12), and the outer most unit laminated body, i.e. the farthest from the substrate (12), is laminated with a covering layer so as to constitute the laminated structure body (14). It is characterized in that the lamination process is to laminate a unit laminated body (11) and a covering layer (13) on the surface of adhesive laminated body (32) of the unit laminated body (11) located at the location farthest away from the substrate (12) of the adhesive structure (31) which includes the substrate (12) and at least one of the unit laminated body (11), and one of the group consisting of these laminated bodies is selected as attachment-layer body (33), and the attachment-layer body (33) layered on the adhesive structure (31) is created to have tensile stress. The lamination process includes: an attachment step for attaching the attachment-layer body (33) to the adhesive structure (31), a force-applying step for applying external force to the attachment-layer body (33), a direction-control step for controlling the direction in which the external force is applied to the attachment-layer body (33) during the force-applying step; and the direction-control step is a step for controlling the direction in which the external force is applied to the attachment-layer body (33) in such a manner that an inter-stress angle (R) of a first direction in the attachment-layer body (33) layered on the applied structure (31), which is the direction of a principal-in-plane component of the tensile stress from the external force, in relation to a second direction in the adhesive-layer body (32), which is the direction of a principal-in-plane component of the tensile stress thereof, is more than 0 degrees and less than 120 degrees.

Description

Method for manufacturing multilayer optical recording medium

The present invention relates to a method of manufacturing a multilayer optical recording medium.

In recent years, optical recording media have attracted attention in terms of being able to record a large amount of recorded data, and have been used for various purposes. Recently, a method of recording data in three dimensions (hereinafter, also referred to as "multilayer optical recording method") has been proposed with the aim of further increasing the density of recording. For example, Y. Kawata is a technique for performing multilayer optical recording on a photopolymer material having a photopolymerizable photoreactive component (for example, refer to Non-Patent Document 1).

The optical medium to be applied to the multilayer optical recording method is described, for example, in the multilayer optical recording medium of Patent Document 1, and the number of optical recording layers included in the multilayer optical recording medium tends to increase year by year, and Patent Document 1 discloses Example, a laminate having 20 layers of optical recording layers.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2011-81860

[Non-patent literature]

[Non-Patent Document 1] Appl. Opt., 35, 2466 (1966)

As a method of manufacturing the above-described multilayer optical recording medium, there is proposed a method in which a substrate is provided with a pressure-sensitive adhesive sheet composed of a laminated optical recording layer and a pressure-sensitive adhesive layer without directly providing a recording layer. However, in the state in which the method of using such a sheet is used, when the number of laminated sheets is increased, the main surface of the medium (the surface parallel to the thickness direction of the medium serves as the normal line) In the inner direction, a strong tensile stress remains, which occurs in a state where the medium is bent. When the degree of bending becomes large, there is a concern that the multilayer optical recording medium may cause a problem of reading when the data is reproduced by using the reproducing device.

The present invention has been made in view of the above circumstances, and a problem thereof is to provide a method of manufacturing a multilayer optical recording medium which reduces the possibility of occurrence of warpage.

The present invention for solving the above problems provides a method for producing a multilayer optical recording medium (Invention 1). In the first aspect, a unit laminate including at least an adhesive layer and an optical recording layer is laminated on one side of a substrate. A method of manufacturing a multilayer optical recording medium comprising a plurality of laminated structures which are formed by laminating a unit layer laminated body which is formed on the farthest position side farthest from the substrate to form a cover layer, and is characterized in that: The method of laminating the surface of the adhesive layered body of the unit laminate which is the farthest position side from the substrate including the adhesive layer of the unit substrate and the at least one unit laminate Unit laminate and the aforementioned cover layer and grouped by these laminates a layered body to be selected from the group, and at the same time, a lamination process for laminating the attached layered body of the adhesive structure to have a tensile stress; the layering process includes: a lamination process to which the layered body is attached to the adhesive structure; an application process for applying an external force to the layered body; and a direction in which the external layer is applied to the layered body by the application process a direction control process; the direction control process controls the external force to be applied to the direction of the attached layered body, so that the tensile stress is caused by the external force of the attached layered body laminated on the adhesive structure. The first direction of the direction of the component in the main surface is equal to or less than 120° with respect to the inter-stress angle R in the second direction which is the direction of the component in the main surface of the tensile stress of the adhesive layer. .

According to the invention (Invention 1), since the external force is controlled when the layered body is laminated, the concentration of the stress of the laminated structure obtained by laminating the cover layer can be reduced. Therefore, a multilayer optical recording medium capable of reducing the possibility of occurrence of warpage can be obtained by the implementation of the above invention.

In the above invention (Invention 1), it is preferable that the application process is at least one of before, during, and after the execution of the attaching process, and the tension and the pressing force are imparted to the attached layered body. At least one process that constitutes an external force (Invention 2).

In the above invention (Invention 2), it is preferable that the application process is performed by an external force imparting member on the side opposite to the opposite side of the opposing surface of the adhesive layered body of the attached layered body. The external force is applied, and the attached layered body is in a state in which tensile stress is applied in the direction of the main surface (Invention 3).

In the above invention (Inventions 1 to 3), it is preferable that the adhesive structure system is rotatable as a rotation axis in a normal direction of the main surface thereof, and the directional control process is performed after the rotation of the adhesive structure Attachment process (Invention 4).

In the above invention (Inventions 1 to 4), it is preferable that the attached layered system is rotatable as a rotation axis in a normal direction of a main surface of the adhesive structure, and the directional control process is to rotate the attachment layer After the shape, the above-described attaching process (Invention 5) is carried out.

In the above invention (Inventions 1 to 5), it is preferable that the unit laminated system includes a hard layer having a layer having a glass transition temperature Tg of 25 ° C or higher (Invention 6).

In the above invention (Inventions 1 to 6), it is preferable that a material for peeling off is laminated on at least one side of the layered body, and the peeling material is peeled off from the attached layered body to expose the attached layered body. The surface of one of the sides is attached to the adhesive structure by the surface of the opposite side of the substrate on the opposite side of the adhesive laminate, and the attached layered body is attached to the adhesive structure (Invention 7).

In the above invention (Inventions 1 to 7), it is preferable that the adhesive structure system laminates a material for peeling off on the surface of the adhesive laminate side, and the adhesive structure is peeled off from the adhesive structure to expose the adhesive layer. The surface of one side of the body is bonded to the surface of one side of the layered body, and the attached layered body is attached to the above-mentioned adhesive structure (Invention 8).

In the above-described invention (Inventions 1 to 8), it is preferable that the above-mentioned laminated structure is formed by the above-mentioned laminated structure in which the cutting process is performed in advance and has a shape corresponding to the shape of the substrate, and is laminated on the adhesive structure (Invention 9) ).

In the foregoing invention (Inventions 1 to 8), it is preferable to have: for the former The layered body is attached, and the cutting process is performed to have a cutting process corresponding to the shape of the substrate (Invention 10).

In the above invention (Inventions 1 to 9), it is preferable that the attaching process is to carry out a bonding process in which the long-side attached layered body is attached to the adhesive structure in a predetermined direction (Invention 11).

In the manufacturing method of the present invention, a lamination process is performed by laminating a layered body, and an external force is applied to each of the layered bodies, and a layered body is laminated in a state of having tensile stress. At this time, the concentration of the stress of the laminated structure obtained by remaining the laminated cover layer can be reduced by controlling the external force. Therefore, a multilayer optical recording medium capable of reducing the possibility of occurrence of warpage can be obtained by the manufacturing method of the present invention.

1, 52, 54‧‧‧ optical recording layer

2, 55‧‧ ‧ adhesive layer

3, 51‧‧‧1st stripping material

4, 56‧‧‧2nd peeling material

11, 11-1, 11-2, 11-3, 11-(n-1), 11-n, 50‧‧‧ unit layer

12‧‧‧Substrate

13‧‧‧ Coverage

14‧‧‧Layered structures

15‧‧‧Adhesive layer

20‧‧‧Multilayer optical recording media

31‧‧‧Adhesive structures

32‧‧‧Adhesive laminate

32a‧‧‧ opposite to the opposite side of the substrate 12 of the adhesive laminate 32

33‧‧‧With layered body

33a‧‧‧ facing the side of the adhesive laminate 32 of the unit laminate 11-4

33b‧‧‧ opposite to the opposite side of the face 33a of the unit laminate 11-4

34, 35‧‧‧ peeling materials

36‧‧‧The normal direction of the main surface of the adhesive structure 31

37, 37-1, 37-2, 37-3, 37-4, 37-5, 37-6, 37-7‧‧‧1st direction

38, 38-1, 38-2‧‧‧2nd direction

41‧‧‧Abutment

42‧‧‧Pressure pressure roller

53‧‧‧Support layer

60‧‧‧The cutting process is performed in advance to form an attached layered body corresponding to the shape of the substrate

Fig. 1 is a schematic cross-sectional view showing a specific example of a unit laminate according to an embodiment of the present invention.

Fig. 2 is a view showing two specific examples of the multilayer optical recording medium according to the embodiment of the present invention, that is, (a) a state in which the unit laminate is laminated by the substrate through the adhesive layer; and (b) a direct layer on the substrate. A schematic cross-sectional view of the state of the product unit laminate.

Fig. 3 is a cross-sectional view conceptually showing a lamination process of a laminated structure according to an embodiment of the present invention.

4 is a perspective view conceptually showing an example of a method of setting the inter-stress angle R of the direction control process according to an embodiment of the present invention, which is shown in (a) The state in which the base is rotated as a direction control process, (b) the end direction control process is set to the state of the inter-stress angle R, and (c) the state in which the process is applied after the application process is performed after the attaching process Picture.

5 is a perspective view conceptually showing an example of a method of setting the inter-stress angle R of the direction control process according to the embodiment of the present invention, and shows a state in which (a) an attempt is made to rotate the layered body as a direction control process, ( b) a state in which the direction control process is set to end the direction control process, and (c) a state in which the direction control process in the case where the application process is performed is completed after the attaching process.

6 is a schematic plan view of the multilayer optical recording medium of the first embodiment and the third embodiment viewed from the upper side, showing the in-plane direction of the tensile stress of each of the unit laminate and the cover layer constituting the multilayer optical recording medium. Figure.

Fig. 7 is a schematic cross-sectional view showing a unit laminate produced in the second embodiment.

Fig. 8 is a front view (i) and a cross-sectional view (ii) showing two specific examples (a) and (b) of an attached layered body which is subjected to a cutting process in advance and which has a shape corresponding to a substrate.

Hereinafter, embodiments of the present invention will be described.

Unit layer

In the method for producing a multilayer optical recording medium according to an embodiment of the present invention, a unit laminate including at least an adhesive layer and an optical recording layer is used in the production.

The unit stratification system is not limited to a specific structure as long as it satisfies the above-mentioned structural requirements. It may be a laminate of an adhesive layer and an optical recording layer, and may be a laminate in which layers other than the adhesive layer, the optical recording layer, the adhesive layer, and the optical recording layer are laminated in this order.

(1) Adhesive layer

The unit laminate of the present invention may be in the form of an adhesive layer, preferably in the form of (A) a non-hardening type adhesive layer and (B) an energy-hardening type adhesive layer.

(A) non-hardening adhesive layer

The adhesive which constitutes the non-curing adhesive layer of the above (1) is used for the adhesion temperature at the time of producing a laminated structure (details are described later), and it is preferable to use it. The optical recording layer has a bonding property. From the viewpoint of optical use, it is preferable that the adhesive is a propylene-based adhesive.

As the propylene-based adhesive system, for example, a (meth) acrylate copolymer and a crosslinking agent can be used. Further, in the present specification, the term "(meth)acrylic acid" means both of acrylic acid and methacrylic acid. Other similar terms are the same.

The (meth) acrylate-based copolymer is preferably an alkyl (meth) acrylate monomer having an alkyl group having 1 to 20 carbon atoms and a monomer including a functional group having an active hydrogen. And copolymers of other monomers used as required.

Here, examples of the alkyl (meth) acrylate monomer having an alkyl group having 1 to 20 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, and propyl (methyl). Acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, amyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate Ester, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, fluorenyl (A) Acrylate, lauryl (meth) acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, stearyl methacrylate (meth) acrylate, and the like. These systems may be used singly or in combination of two or more.

On the other hand, as an example of a monomer including a functional group having an active hydrogen, a series of 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl group Hydroxyalkyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, etc. Acrylate; monomethylaminoethyl (meth) acrylate, monoethylaminoethyl (meth) acrylate, monomethylaminopropyl (meth) acrylate, monoethylamine Monoalkylaminoalkyl (meth) acrylate such as propyl (meth) acrylate; ethylene of acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, citraconic acid, etc. Sexually unsaturated carboxylic acids and the like. These single systems may be used singly or in combination of two or more.

Further, examples of other monomers used as required include vinyl esters such as vinyl acetate and vinyl propionate; olefins such as ethylene, propylene, and isobutylene; and halogenated olefins such as vinyl chloride and vinylidene chloride. a styrene monomer such as styrene or α-methylstyrene; a diene monomer such as butadiene, isoprene or chloroprene; and a nitrile such as acrylonitrile or methacrylonitrile. Monomer; acrylamide such as acrylamide, N-methyl acrylamide, N,N-dimethyl decylamine or the like. These systems may be used singly or in combination of two or more.

In the propylene-based adhesive, (methyl) as a resin component is used. The acrylate-based copolymer is not particularly limited in its copolymerization form, and may be any of random, block, and graft copolymers. Further, the molecular weight is preferably in the range of 200,000 to 2,000,000 in terms of a weight average molecular weight.

Further, the weight average molecular weight is a polystyrene-converted value measured by gel permeation chromatography (GPC).

In the present invention, the (meth) acrylate-based copolymer may be used singly or in combination of two or more.

(B) Energy hardening adhesive layer

On the other hand, the adhesive constituting the energy-curing adhesive layer is an energy-hardening type, and has adhesiveness at the bonding temperature at the time of producing the laminated structure, and preferably has adhesion to the optical recording layer, and at the same time It is hardened by applying energy such as heat or light to increase the hardness, and has a function of attaching a structure to the laminated structure which is not easily pressed.

The energy-hardening type adhesive is not particularly limited as long as it can have the above-described functions and is used for optical applications, and can be appropriately selected and used among the conventional energy-hardening adhesives.

As such an energy hardening type adhesive, for example, a thermosetting type and an energy ray hardening type adhesive can be used. Further, the energy-curing type adhesive is propylene-based, fluorenone-based or rubber-based. However, in the present invention, from the viewpoint of optical use, an energy-curable propylene-based adhesive is preferable. Examples of the energy ray system include ultraviolet rays or electron beams.

The energy-curable propylene-based adhesive agent may, for example, be (a) an adhesive comprising an adhesive propylene-based polymer and an energy-curable polymerizable oligomer and/or a polymerizable monomer and a polymerization initiator as required. (b) An adhesive propylene-based polymer (hereinafter referred to as "energy-curable copolymer") which is formed by introducing an energy-hardening functional group having a polymerizable double bond in a side chain, and a polymerization initiator as required Contains adhesives, etc.

In the adhesive of the above (a), the adhesive propylene polymer is preferably an alkyl (meth) acrylate having an alkyl group having 1 to 20 carbon atoms and an active hydrogen which is used as required. The functional group includes a copolymer of a monomer and other monomers. The (meth) acrylate copolymer is as described in the propylene-based adhesive which is shown in the adhesive layer constituting the above (A). In the state in which the (meth) acrylate-based copolymer is used as the resin component of the energy-curing adhesive, the molecular weight is preferably 300,000 or more in terms of a weight average molecular weight.

Further, examples of the energy curing type polymerizable oligomer include a polyester acrylate type, an epoxy acrylate type, an urethane acrylate type, a polyether acrylate type, a polybutadiene acrylate type, and a ruthenium. Ketone acrylates and the like.

Here, as the polyester acrylate-based oligomer, a polyester oligo having a hydroxyl group at both terminals can be obtained by esterifying, for example, a condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth)acrylic acid. The hydroxyl group is obtained by esterifying a hydroxyl group at the terminal of the oligomer obtained by adding an epoxide to the polyvalent carboxylic acid by (meth)acrylic acid to obtain a polyester acrylate-based oligomer.

The epoxy acrylate oligomer can be esterified by reacting (meth)acrylic acid with, for example, a relatively low molecular weight bisphenol type epoxy resin or an oxirane ring of a novolac type epoxy resin. An epoxy acrylate oligomer was obtained. In addition, it is also possible to use partial denaturation by means of a dibasic carboxylic anhydride. A carboxyl-denatured epoxy acrylate oligomer of the epoxy acrylate-based oligomer.

The urethane acrylate oligomer can be obtained by esterifying, for example, a polyether polyol or a polyester polyol with a polyisocyanate by esterification with (meth)acrylic acid. a polymer to obtain a urethane acrylate oligomer, and a polyol acrylate oligomer can obtain a polyol by esterifying a hydroxyl group of a polyether polyol with (meth)acrylic acid Acrylate oligomer.

The weight average molecular weight of the polymerizable oligomer is a converted value of a standard polymethyl methacrylate measured by a GPC method, preferably 500 to 100,000, more preferably 1,000 to 70,000, or even preferably 3,000. Selected within the range of ~40,000.

One type of the polymerizable oligomer may be used alone or two or more types may be used in combination.

On the other hand, examples of the energy curing type polymerizable monomer include cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, and stearin (A). Monofunctional acrylates such as acrylates and isobornyl (meth)acrylates, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(methyl) Acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, hydroxytrimethylacetate Pentyl glycol di(meth)acrylate, dicyclohexanyl di(meth)acrylate, caprolactone denaturing dicyclopentenyl di(meth)acrylate, ethylene oxide denaturing phosphate di(a) Acrylate, allylated cyclohexyl di(meth)acrylate, Isocyanate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid denatured dipentaerythritol tri(meth)acrylate, pentaerythritol tris(methyl) Acrylate, propylene oxide-denatured trimethylolpropane tri(meth)acrylate, tris(propyleneoxyethyl)isocyanate, propionic acid-denatured dipentaerythritol penta(meth)acrylate, dipentaerythritol A polyfunctional acrylate such as acrylate or caprolactone denatured dipentaerythritol hexa(meth) acrylate. These polymerizable single-systems may be used alone or in combination of two or more.

Further, as a polymerization initiator to be used as required, an organic peroxide or an azo-based compound is used in a state where the energy-curing adhesive is a thermosetting type. Examples of the organic peroxide series include dialkyl peroxides such as di-t-butyl peroxide, t-bochi cumyl peroxide, and dicumyl peroxide, and acetaminophen. Oxide-based peroxides such as oxides, lauryl peroxide, benzoquinone peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethyl a ketone peroxide such as cyclohexanone peroxide or methylcyclohexanone peroxide, or a ketone condensate such as 1,1-bis(t-butylperoxy)cyclohexane, t- Butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, p-decane hydroperoxide, diisopropylbenzene hydroperoxide Hydroperoxides such as 2,5-dimethylhexane-2,5-dihydroperoxide, t-butyl peroxyacetate, t-butylperoxy-2-ethylhexyl A peroxy ester such as an acid ester, t-butyl peroxybenzoate or t-butyl peroxy isopropyl carbonate.

Further, as an azo-based compound series, 2,2-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(4-cyclopropylpropane) Nitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1 '-Azobis(cyclohexane-1-carbonitrile), 2-(aminomethylmercaptoazo)isobutyronitrile, 2-phenylazo-4-methoxy-2,4-dimethyl Kevalonitrile and the like.

These polymerization initiators may be used alone or in combination of two or more.

On the other hand, in the state where the energy-hardening type adhesive is an energy ray-curable type, ultraviolet rays or electron beams are usually irradiated as an energy ray system, but when ultraviolet rays are irradiated, photopolymerization initiation can be used as a polymerization initiator. Agent. As the photopolymerization initiator series, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin Butyl ether, acetophenone, dimethylaminoethyl benzene, 2,2-dimethoxy-2-phenyl acetophenone, 2,2-diethoxy-2-phenyl acetophenone , 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2 -morpholine-propan-1-one, 4-(2-hydroxyethoxy)phenyl-2(hydroxy-2-static) ketone, benzophenone, p-phenylbenzophenone, 4, 4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methyloxime, 2-ethylhydrazine, 2-tert-butylhydrazine, 2-aminopurine, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethyl Ketoacetal, acetophenone ketal, p-dimethylamine benzoate, low [2-hydroxy-2-methyl-1-[4-(1-propenyl)phenyl]propane ]Wait. These types may be used alone or in combination of two or more.

Next, the adhesive agent of the above (b) is an adhesive propylene-based polymer which is formed by introducing an energy-hardening functional group having a polymerizable double bond in a side chain, and examples thereof include the adhesive of the above (a). The polymer chain of the adhesive propylene-based polymer is introduced, and an active point of -COOH, -NCO, epoxy group, -OH, -NH ₂ or the like is introduced, and a compound having the active point and the polymerizable double bond is reacted and introduced into The side chain of the adhesive propylene-based polymer is composed of an energy-hardening functional group having a polymerizable double bond.

In order to introduce the above-mentioned active point into the adhesive propylene-based polymer, it is possible to have a function of -COOH, -NCO, epoxy group, -OH, -NH ₂ or the like at the time of producing the adhesive propylene polymer. The monomer or oligomer of the group and the polymerizable double bond coexist in the reaction system.

Specifically, in the case where the adhesive propylene-based polymer described in the above (a) is used as an adhesive, a (meth)acrylic acid or the like can be used in a state in which a -COOH group is introduced, and a -NCO group can be introduced. In the state where (meth)acryloxyethyl isocyanate or the like is used, a glycidyl (meth)acrylate or the like is used in a state in which an epoxy group is introduced, and in a state in which an -OH group is introduced, 2 is used. - hydroxyethyl (meth) acrylate, 1,6-hexane diol mono (meth) acrylate, etc., in the state of introducing -NH ₂ group, using N-methyl (meth) acrylamide Wait.

The compound having a polymerizable double bond which reacts with these active sites may be, for example, (meth)acryloxyethyl isocyanate, epoxypropyl (meth)acrylate, pentaerythritol mono(meth)acrylate, Among the dipentaerythritol mono(meth)acrylate and trimethylolpropane mono(meth)acrylate, etc., it is appropriately selected and used in accordance with the type of the active site.

In this way, the side chain of the adhesive propylene polymer is obtained. An adhesive propylene-based polymer composed of an energy-curable functional group having a polymerizable double bond is introduced as the active site.

Further, as a polymerization initiator to be used as required, an organic peroxide or an exemplified in the above description of the adhesive of (a) may be used in a state in which the energy-hardening adhesive is a thermosetting type. A nitrogen based compound. On the other hand, in the state in which the energy-hardening type adhesive is an energy ray-curable type and ultraviolet rays are used as an energy ray, the photopolymerization initiator which is exemplified in the above-mentioned (a) adhesive can be used.

The crosslinking agent, the adhesion-imparting agent, the oxidation inhibitor, the ultraviolet absorber, the light stabilizer, the softener, the filler, etc. may be added to the adhesive constituting the adhesive layer without impairing the effects of the present invention. .

Examples of the crosslinking agent include a polyisocyanate compound, an epoxy resin, a melamine resin, a urea resin, a dialdehyde, a methylol polymer, an aziridine compound, a metal chelate compound, a metal alkoxide, and a metal salt. Etc. However, it is preferable to use a metal chelate compound which does not easily cause a change in light transmittance due to discoloration (yellowing) of the adhesive layer.

Here, examples of the polyisocyanate compound include aliphatic polyisocyanates such as phenylene diisocyanate, diphenylmethane diisocyanate, and phenylene diisocyanate, and aliphatic groups such as hexamethylene diisocyanate. An alicyclic polyisocyanate such as polyisocyanate, isophorone diisocyanate or hydrogenated diphenylmethane diisocyanate, and these biuret, isocyanate, or even ethylene glycol, propylene glycol, and neopentyl An adduct of a reactant containing a low molecular weight active hydrogen compound such as an alcohol, trimethylolpropane or castor oil. Further, examples of the metal chelate compound include an aluminum chelate compound and the like. These ones One type of the crosslinking agent may be used alone or two or more types may be used in combination. In the state containing a crosslinking agent, in order to accelerate the progress of the crosslinking reaction, an accelerator composed of an organometallic compound or the like may be contained.

The thickness of the adhesive layer is not particularly limited, but is usually from 1 to 30 μm, preferably from 2 to 20 μm. If it is such a thickness, the state of bonding with the optical recording layer becomes good.

(2) Optical recording layer

The material constituting the optical recording layer to be included in the unit laminate of the present invention is not particularly limited as long as it can contain a photosensitive material (photoreactive component), and is an optical recording layer of a conventional optical recording medium. The constituent materials can be used by appropriately selecting any of the known materials. Examples of such a material include those obtained by separately forming a photosensitive material or materials constituting a substrate to contain a photosensitive material.

The material constituting the substrate may be an inorganic material or an organic material. However, from the viewpoint of the ease of manufacture of the unit laminate or the type of material selected, it is preferably organic. Polymer Materials. The polymer material may be a homopolymer or a copolymer, and is not particularly limited in terms of the type, molecular weight, polymerization form, and the like of the monomer.

Specific examples of the polymer material include various polyethylenes, ethylene/1-butene copolymers, ethylene/4-methyl-1-pentene copolymers, ethylene/1-hexene copolymers, and polypropylene. Ethylene/propylene copolymer, propylene/1-butene copolymer, poly-1-butene, 1-butene/4-methyl-1-pentene copolymer, poly 4-methyl-1-pentene, poly Polyolefins such as 3-methyl-1-butene, ethylene/cyclic olefin copolymer, and cyclic olefin resin, ethylene/acetic acid B Poly(meth)acrylate, polyethylene terephthalate, polyethylene naphthalene, etc. of an olefin copolymer, an ethylene/acrylic acid copolymer or a metal salt thereof, a polymethyl methacrylate, an alicyclic propylene resin, or the like A polyester resin such as a formate or a fluorine-based resin such as a polyperfluoroethylene or a perfluoroalkenyl vinyl ether polymer, polystyrene, polyvinyl alcohol, polycarbonate, polyphenylene sulfide, or poly Ether oxime, polyimide, polyphenylene oxide, olefin/N-substituted maleic anhydride imide copolymer, allyl carbonate resin, epoxy acrylate resin, urethane acrylate resin, etc. . These polymer materials may be used alone or in combination of two or more.

On the other hand, the photosensitive material may be chemically bonded to the above-mentioned substrate to form a main chain or a side chain component, or may be dispersed or dissolved only in the matrix. The photosensitive material system is not particularly limited, but a multiphoton absorption material is preferably used.

The multiphoton absorptive material is a compound having a property of simultaneously absorbing two or more photons and migrating to an excited state. In addition, it is preferable to include a photon absorption material having a 2-photon absorption cross-sectional area of 0.1 GM or more, and more preferably 100 GM or more, from the viewpoint of obtaining a sufficient recording sensitivity in practical use. 2 photon absorbing materials. Such a material may be, for example, a single photon absorbing material alone or a reactive compound such as a multiphoton absorbing material and a change in energy from the excited multiphoton absorbing material. The constructor is configured by combining the materials of the base body by the need of cooperation.

In addition, the aforementioned "GM" system means 10 - ⁵⁰ cm ^4. s ^. Molecule ^-1. Photon ^-1 . The material constituting the substrate may be an inorganic material or an organic material. However, it is preferably an organic system because of the ease of manufacture of the unit laminate or the type of material selected. Molecular material. The polymer material may be a homopolymer or a copolymer, and the type, molecular weight, polymerization form, and the like of the monomer are not particularly limited, and examples thereof include polymethyl methacrylate.

The multiphoton absorbing material may be chemically bonded to the substrate to form a main chain or a side chain component, or may be dispersed or dissolved only in the matrix. The multiphoton absorptive material is not particularly limited, and various compounds can be used. For example, a cyanine compound, a styryl compound, a pyrylium compound, a thiopyranium compound, a phthalocyanine compound, an allyl compound, an oxy alcohol compound, a squaraine compound, a cyanine compound, a coumarin compound, a pyran compound, etc. , hydrazine compound, hydrazine compound, triphenylmethane compound, diphenylmethane compound, xanthene compound, thioxanthene compound, phenothiazine compound, azo compound, methylimine compound, anthrone compound, diaryl a vinyl compound, a spiropyran compound, a fulgide compound, a perylene compound, a polyene compound, a diphenylamine compound, a quinophthalone compound, a cyanine compound, a porphyrin compound, a phthalocyanine compound, a styrene compound, A compound such as a phenylene ethylene compound, a triphenylamine compound or an oxazole compound.

As a series of recordings using such a multiphoton absorbing compound, for example, a material which is anisotropically light-like by using a compound containing an azo group or a C=C group or a C=N group, or just as (methyl) An acrylate compound, a material that causes polymerization by light, a material that causes reversible structural changes by light, such as an organic photochromic material, an organic refractive material that causes charge distribution by light, and the like, and read refraction Way of modulation; use by light a material that changes the fluorescence characteristics, a method of reading fluorescence; a combination of a material that generates an acid by light and an acid chromogenic compound or a combination of a decolorizer and a decolorizing compound, and a read modulation or refractive index The method of modulation, etc. In these recording modes, the multiphoton absorbing compound itself may have such photoreactivity, and may also be moved to other reactivity by energy by a multiphoton absorbing compound excited by absorption of multiphotons. The movement of the compound causes a reaction.

The thickness of the optical recording layer is not particularly limited as long as it can exhibit an optical recording function. It is usually from 1 to 5000 nm, preferably from 10 to 4000 nm.

The unit laminated system of the present embodiment may include, as needed, a layer for reinforcing the unit laminate, and for providing positional information in the interior of the multilayer optical recording medium, having irregularities on the surface as recording pits and/or The position information imparting layer of the groove, and the adhesive layer such as the optical waveguide layer, the reflective layer, and the dielectric layer, and the layer other than the optical recording layer. In the present embodiment, layers other than the adhesive layer and the optical recording layer are collectively referred to as "other layers".

(3) Hard layer

In the present embodiment, the "hard layer" means that the glass transition temperature Tg of the material constituting the hard layer is 25 ° C or higher. From the viewpoint of more securely protecting the optical recording layer, the glass transition temperature Tg is preferably 30 ° C or higher, more preferably 35 ° C or higher.

The upper limit of the glass transition temperature Tg of the hard layer is not particularly limited. However, since the degree of shrinkage in the production process is also large due to the composition, the glass transition temperature Tg is preferably 400 ° C or lower, more preferably 350 ° C. the following. Further, the hard layer system preferably has a storage modulus of 10 ⁷ Pa or more, more preferably 10 ⁸ Pa or more. Further, the hard layer system preferably has a storage modulus of 10 ¹² Pa or less, more preferably 10 ¹¹ Pa or less.

The material constituting the hard layer is not particularly limited. Hereinafter, a hard layer which is a layered body (other layer) other than the adhesive layer and the optical recording layer and which is provided for the purpose of reinforcing the unit laminated body is also referred to as a "support layer".

The hard layer which is composed of a different material different from the material constituting the adhesive layer is exemplified by a resin film. Examples of the resin to be imparted to the hard layer include polyvinyl chloride (Tg: 87 ° C), polystyrene (Tg: 100 ° C), polyamine 6 (Tg: 50 ° C), and polycarbonate (Tg: 150 ° C). ), polyphenylene sulfide (Tg: 126 ° C), polyether oxime (Tg: 230 ° C), polyamidoximine (Tg: 275 ° C), polylactic acid (Tg: 57 ° C), polytetrafluoroethylene (Tg: 126 ° C), polyvinyl fluoride fork (Tg: 35 ° C), polybutylene terephthalate (Tg: 50 ° C), polyethylene terephthalate (Tg: 69 ° C), Polymethyl methacrylate (Tg: 100 ° C), polyfluorene (Tg: 180 ° C), polyarylate (Tg: 190 ° C), and the like. Further, the hard layer may be formed of a material such as a conventional energy ray-curable copolymer. Further, a hard layer system containing such a material may also be in a state of being a constituent element of a coating layer described later.

The arrangement relationship between the adhesive layer of the unit laminate and the optical recording layer, and other layers provided for the purpose of blending is also arbitrary. The unit laminated system composed of the laminated adhesive layer and the optical recording layer is the simplest structure among the unit laminated bodies. In the state where the unit laminate includes other layers, other layers may be laminated between the adhesive layer and the optical recording layer, and may be laminated on the side opposite to the adhesive layer opposite to the optical recording layer. The opposite side. It is possible to laminate a plurality of other layers in a unit layer. The unit stratification system is preferably an adhesive The layer is in the outermost layer on at least one side.

If it is a specific example which shows the structure which can be obtained by a unit laminated body, the following structures are mentioned.

^. Unit layer body arranged in the order of the recording layer and the adhesive layer

^. Unit laminate according to the order of the adhesive layer, the recording layer, and the adhesive layer

^. Unit layer body arranged in the order of recording layer, other layer, and adhesive layer

^. Unit layer body arranged in the order of other layers, recording layers, and adhesive layers

^. Unit laminate according to the order of the adhesive layer, the recording layer, the other layer, and the adhesive layer

^. Unit laminate according to the order of the adhesive layer, other layers, recording layer, and adhesive layer

In addition, in the case of a specific example in a state in which the unit layer is displayed to include the support layer and the other layer is used, the following structures are listed.

^. Unit stratified body arranged in the order of support layer, recording layer, support layer, and adhesive layer

^. Unit layer body arranged in the order of the recording layer, the support layer, the recording layer, and the adhesive layer

^. Unit layer body arranged in the order of the recording layer, the support layer, the adhesive layer, the recording layer, and the adhesive layer

^. Unit layer body arranged in the order of the recording layer, the support layer, and the adhesive layer

^. Unit layer body arranged in the order of support layer, recording layer, and adhesive layer

^. Unit layer body arranged in the order of support layer, recording layer, support layer, recording layer, and adhesive layer

^. Unit laminate according to the order of the adhesive layer, the support layer, the recording layer, the support layer, and the adhesive layer

^. Unit layer body arranged in the order of the adhesive layer, the recording layer, the support layer, the recording layer, and the adhesive layer

^. Unit laminate according to the order of the adhesive layer, the recording layer, the support layer, the adhesive layer, the recording layer, and the adhesive layer

^. Unit laminate according to the order of the adhesive layer, the recording layer, the support layer, and the adhesive layer

^. Unit layer body arranged in the order of the adhesive layer, the support layer, the recording layer, the support layer, the recording layer, and the adhesive layer

(4) Stripping materials

It is possible to provide a material for peeling off from the unit layer laminate to the surface on the side of the adhesive layer, and to provide a material for peeling off as a member for protecting the surface of the recording layer or the like. A carrier of each layer of a film adhesive layer, a recording layer, or the like. As long as the material for peeling is exfoliating, various synthetic resin films which have such releasability can be used as a material for peeling. Specific examples thereof include a polyester film of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, a polyethylene film, a polypropylene film, a polyvinyl chloride film, and a poly a vinylidene chloride film, a polyvinyl alcohol film, an ethylene-vinyl acetate copolymer film, a polystyrene film, a polycarbonate film, a polymethylpentene film, a polyfluorene film, a polyetheretherketone film, a polyether film, Polyphenylene sulfide film, polyether quinone film, polyimine film, fluororesin film, polyamide film, acryl resin film, raw spinel resin film, cycloolefin resin film, cellulose acetate resin, etc. . Thickness of stripping material The degree system is not particularly limited, but is usually 5 to 500 μm, preferably 10 to 200 μm.

In addition, the peeling material can be peeled off on the surface of the base material of the peeling material on the side corresponding to the peeling surface side of the peeling material, and the peeling material can be obtained. The resin film is exemplified as the substrate in this state, and is also composed of a paper-based material such as high-quality paper. The release treatment series is a method in which a conventional release agent such as an anthrone-based release agent, a polybutadiene-based release agent, a fluororesin-based release agent, or an alkyd-based release agent is applied to at least one side of a substrate. The thickness of the release agent layer obtained by applying the release agent is not particularly limited, and may be set as required, but is usually 0.05 to 50 μm. Further, in order to improve the adhesion to the surface of the substrate before the application of the release agent, for example, corona discharge treatment, plasma discharge treatment, chromic acid treatment, flame treatment, hot air can be performed. Treatment, ozone ^. UV irradiation treatment, etc.

The peeling force of the material for peeling is preferably 10 to 700 mN/25 mm. When the peeling force is in this range, the unit laminated body is not excessively deformed, and the surface on the side of the adhesive layer can be exposed, which is preferable from the viewpoint of improving workability. The more ideal peeling force is 30~500mN/25mm.

In addition, in view of the thickness accuracy of the optical recording layer and the adhesive layer of the unit laminate, and the handleability, etc., it is preferable to manufacture the unit in a state in which both surfaces are attached to the peeling material. The laminate is appropriately peeled off from these peeling materials at the time of use.

Further, it is preferable that the filler is not present on the peeling surface of the peeling material.

(5) Manufacturing method of unit laminate

The manufacturing method of the unit laminate is not particularly limited. The layers of the unit laminate can be formed by lamination in a moderate manner. The layering method of each layer is also not particularly limited, and it can be formed by a so-called wet process, or can be formed by a so-called dry process.

Hereinafter, a method of manufacturing the unit laminate 11 shown in Fig. 1 will be described as an example of a method of manufacturing a laminate including a unit laminate.

The unit laminated body 11 shown in Fig. 1 is a laminated body composed of one layer of the optical recording layer 1 and one layer of the adhesive layer 2, and the first peeling is provided on the surface of both the unit laminated bodies 11 The material 3 and the second peeling material 4 were used.

The method for producing the unit laminate 11 is not particularly limited. However, as a specific example of the method for producing the unit laminate 11 of the layer structure shown in Fig. 1, for example, the method shown below can be used.

First, on the peeling surface of the first peeling material 3, a conventional coating means, for example, a doctor blade method, a roll coating method, a bar coating method, a blade coating method, or a die coating method a gravure coating method or the like, and coating a coating liquid containing a material for forming an optical recording layer at an appropriate concentration so that the thickness of the dried coating film has a predetermined thickness, and drying to form the optical recording layer 1 A first layered body composed of the optical recording layer 1 and the first peeling material 3.

On the other hand, on the peeling surface of the second peeling material 4, a conventional method, for example, a doctor blade method, a roll coating method, a bar coating method, a blade coating method, or a die coating method a gravure coating method or the like, and coating a coating liquid for forming the adhesive layer 2 (the solvent is appropriately set by the composition of the adhesive layer), so that the thickness of the dried coating film becomes a prescribed thickness. , drying, A second laminate composed of the adhesive layer 2 and the second peeling material 4 was produced.

Then, the first laminate is obtained by laminating the surface of the second laminate on the side of the adhesive layer 2 and the surface of the first laminate on the side of the optical recording layer 1 by a rubber press or the like. With the laminate of the second laminate, the unit laminate 11 having the structure shown in Fig. 1 in which the release material 3 and the release material 4 are provided is obtained.

2. Multilayer optical recording media

In the multilayer optical recording medium of the present embodiment, the unit laminated body is laminated on a plurality of sides of the substrate, and the unit laminated body to be laminated on the farthest position side farthest from the substrate. A laminated structure composed of a cover layer is included. Specifically, the multilayer optical recording medium 20 is as shown in Fig. 2, and the plurality of unit laminated bodies, that is, the unit laminated body 11-1, the unit laminated body 11-2, ^''' , and the unit laminated product. The body 11-(n-1) and the unit layered body 11-n are laminated on the side of one side of the substrate 12, and will be laminated on the farthest side farthest from the substrate 12 ( The laminated structure 11 composed of the unit laminate 11-n on the upper side of Fig. 1 to laminate the cover layer 13 is included as a basic structure. As shown in FIG. 2, if the laminated structure 14 is still directly in the state of the multilayer optical recording medium 20, for example, a printed layer or the like is formed on one side of the laminated structure 14. The state in which the multilayer optical recording medium 20 is obtained occurs. Alternatively, as described later, the state in which the multilayer optical recording medium 20 is obtained by performing the cutting process on the members (unit laminate, cover layer, and the like) constituting the laminated structure 14 may be employed.

Further, the laminated structure 14 shown in Fig. 2 is composed of the unit laminated body 11-1 to the unit laminated body 11-n, and the optical recording layer 1 and the adhesive are used. It is composed of layer 2, but is not limited thereto. The unit laminate system can obtain the various configurations described above, and the laminate structure 14 can include a unit laminate including different structures. For example, the unit laminate 11-1 to the unit laminate 11-n includes a unit laminate composed of the optical recording layer 1 and the adhesive layer 2, and includes a support layer and an optical recording layer 1 and adhesion. The unit laminate of the structure in which the agent layer 2 is composed may be laminated, and the order of lamination may be appropriately selected in accordance with the intended laminated structure.

(1) Substrate

The specific shape or composition of the substrate 12 included in the multilayer optical recording medium 20 of the present embodiment should be appropriately set in accordance with the intended multilayer optical recording medium 20. For example, as a material series, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, and polyolefin resin materials are used. Further, the shape series having a thickness of several tens to several hundreds of μm and viewed from the main surface side has a so-called disc shape having a loop shape including a through hole in the thickness direction at the center portion of the main surface.

The substrate 12 may be composed of one type of member, and may be composed of a plurality of members. For example, a plurality of sheet-like members composed of the above resin-based materials may be bonded.

(2) Cover layer

The material of the cover layer 13 which is included in the multilayer optical recording medium 20 of the present embodiment is not particularly limited, and may be appropriately selected and used from among the cover layers of the optical recording medium. Examples of the material thereof include polymethyl methacrylate, polycarbonate, polyethylene terephthalate, and polyolefin-based plastic films (hereinafter referred to as plastic films). The thickness of the plastic film is There is no particular limitation, but it is usually from 20 to 600 μm, preferably from 20 to 150 μm. Further, it is preferable that the plastic film is not stress-extended, and the stress relaxation treatment after the stretching treatment is less, and the stress remaining in the interior is less, and the force and the position imparted to the cover layer 13 are increased to be a part of the laminated structure 14 . The cover layer 13 in the state has a correlation with the component in the main plane of the internal stress.

The cover layer 13 may be composed of one type of member, and may be composed of a plurality of members. For example, a plurality of sheets of the aforementioned plastic film may be laminated. Alternatively, an adhesive layer may be provided on the side opposite to the unit laminate 11 of the cover layer 13, or the hard layer may be included. Further, in the laminated structure 14 shown in Fig. 2(a), the cover layer 13 is laminated on the side of the adhesive layer 2 of the unit laminate 11 without including such an adhesive layer. display. As shown in Fig. 2(b), in the state in which the adhesive layer 15 is laminated on the cover layer 13, from the viewpoint of storage stability of the adhesive layer 15, etc., it is possible to form a laminated structure until the layering The peeling material is attached to the surface of the layer of the cover layer 13 and the adhesive layer 15 on the side of the adhesive layer 15 in one part.

Further, in the laminated structure 14 shown in Fig. 2(a), the unit laminated body 11-1 which is the lowermost layer is laminated on the substrate 12 through the adhesive layer 15, and is opposed to the side of the optical recording layer 1 surface. The relationship between the unit laminated body 11-1 of the laminated structure 14 of the present embodiment and the substrate 12 is not limited thereto. For example, as shown in FIG. 2(b), the unit laminate 11-1 can be laminated on the substrate 12 with respect to the substrate 12 to face the surface of the adhesive layer 2, and the unit laminate 11-1 can be used. The substrate 12 can be fixed by the adhesion of the adhesive layer 2 which is a component of its own composition. In this state, in stratification The unit laminate 11-n which is farthest from the farthest position side of the substrate 12 is laminated on the cover layer 13 through the adhesive layer 15.

3. Method for manufacturing multilayer optical recording medium

In the method of manufacturing a multilayer optical recording medium of the present embodiment, a method of laminating a plurality of unit laminates 11 on a substrate 12 and laminating a cover layer 13 at the end is used as a basic process (hereinafter referred to as " The sequential lamination process"), in this respect, is common to the manufacturing method of the prior art multilayer optical recording medium.

However, when a multilayer optical recording medium is manufactured by the sequential lamination process, the multilayer optical recording medium has a residual stress which is caused by the residual surface stress of the laminated optical body of the obtained multilayer optical recording medium or the manufacturing process thereof The state of the laminated structure of the optical recording medium or its manufacturing process occurs.

In order to solve the problem of the bending, the method of manufacturing the multilayer optical recording medium of the present embodiment is a sequential lamination process including the lamination process described below.

In describing the manufacturing method of the present embodiment, the definition of the term is used here using FIG.

Fig. 3 is a structure in which the fourth layer is integrally formed on the substrate 12 and the unit laminates 11-1, 11-2, and 11-3 which are laminated on one side of the substrate 12, and is conceptually displayed. A cross-sectional view of the state in the process of the unit laminate 11-4.

(adhesive structure)

In the present embodiment, the structure including the substrate 12 and at least one unit laminate 11 is referred to as an adhesive structure 31, and in FIG. The structural system composed of the unit laminates 11-1, 11-2, and 11-3 serves as the adhesive structure 31. Further, the unit laminated body 11 located at the farthest position side of the substrate 12 farthest from the adhesive structure 31 is referred to as an adhesive laminated body 32, and in Fig. 3, the unit laminated body 11-3 is adhered. Laminated body 32.

Further, the adhesive structure 31 may be laminated with a material for peeling off (not shown) on the side of the adhesive laminate 32 side. In this state, the peeling material is peeled off by the adhesive structure 31, and the surface 32a of one side of the adhesive laminate 32 is exposed, and the surface 32a and the surface 33b of one side of the layered body 33 are attached. On the other hand, the layered body 33 is attached to the adhesive structure 31. By thus, the adhesive structure 31 has a material for peeling off, and the surface 32a of one side of the adhesive laminate 32 is protected.

(with layered body)

The unit laminated body laminated on the adhesive laminate 32 is referred to as an attached layered body 33. In FIG. 3, the unit laminated body 11-4 is a laminated layered body 33.

Although not shown, the laminated layer 33 should be laminated on the layered body of the adhesive laminate 32. Therefore, the layered body 33 is also provided as a coating layer. Further, at least one unit laminate may be laminated to form a cover layer (the state including the adhesive layer as described above). Further, the layered body 33 may be laminated to form a plurality of unit laminates. In this state, the plurality of unit stack systems of the layers may be the same, and may be different from each other.

The shape of the layered body 33 is not particularly limited. As shown in FIG. 3, it may correspond to the shape of the substrate 12, and may also have a long-length shape as shown in FIG. 4 or FIG. The attached layered body 33 is long. In the state in which the laminated layer 33 is laminated on the adhesive layered body 32, it can be cut into a shape corresponding to the substrate 12.

In addition, in FIG. 3, the unit laminated bodies 11-1 to 11-4 are composed of the optical recording layer 1 and the adhesive layer 2, but the various structures described above can be obtained by the unit laminated system, and are not limited thereto.

In addition, the layered body 33 may be laminated on at least one side of the layered body 33 to be laminated (see FIG. 3 as the materials for peeling 34, 35). By providing the layered body 33 with the material for peeling as described above, it is possible to improve the rationality of the layered body 33, and after laminating the contaminated or adhered layered body 32, the attached layered body 33 is reduced. The possibility of stripping. In this state, the peeling material which is close to the surface facing the adhesive layered body 32 (in FIG. 3, the peeling material 34) can be peeled off by the lamination process to expose the opposing unit. The side surface 33b of the adhesive laminate 32 of the laminate 11-4 is bonded to the surface 33b and the surface 32a opposite to the substrate 12 of the adhesive laminate 32, and the layered body 33 is attached. Attached to the adhesive laminate 32.

The method for producing a multilayer optical recording medium according to the present embodiment includes: starting from the substrate 12 including the substrate 12 and at least one of the adhesive structures 31 of the unit laminated body 11, and unit stacking at the farthest position side The surface of the body 11 (in Fig. 3, which becomes the unit laminate 11-3) on the side of the adhesive laminate 32 (i.e., opposite to the face 32a opposite to the side opposite to the substrate 12 of the adhesive laminate 32) The laminated unit laminate 11 and the cover layer 13 and the attached layered body 33 selected by the group of the laminates (in FIG. 3, the unit laminate 11-4) are in an adhesive structure. On the body 31, at the same time, it is in a state in which the laminated layer 33 is laminated on the adhesive structure 31 to have tensile stress. Lamination process.

(layering process)

In the lamination process of the present embodiment, the layered body 33 is laminated on the surface of the adhesive structure 31 on the side of the adhesive laminate 32, and the layered body 33 is laminated on the adhesive structure 31. It has a state of tensile stress.

In order to be in such a state, the lamination process includes a process of attaching the layered body 33 to the adhesion structure 31 and attaching an external force to the attached layer body as a sub-process for constituting the lamination process. The application process of 33 and the control of the direction in which the direction of the external force is applied by attaching the layered body 33 by the application process are controlled; the relative relationship of the start times of these processes is changed in accordance with the specific contents of these processes. Hereinafter, the process and the direction control process will be described in detail.

(1) Attachment process

The attaching process is attached to the adhesive structure 31 by attaching the layered body 33. The specific attachment method is arbitrary, and the attachment process and the application process can be repeatedly performed by applying tension and attaching. In addition, in the state in which the layered body 33 is provided in a long length, the attaching process system preferably transports the attached layered body of a long length in a predetermined direction, and is attached to the adhesive structure 31.

(2) application process

The application process is as described above, and the external force is applied to the additional layered body 33, and the application of the application process can be performed by laminating the layered body 33 to have an angle of stress satisfying the following description. The state of the tensile stress of the condition is effectively prevented from being caused by residual stress in the direction of the principal surface of the laminated optical structure 20 of the obtained multilayer optical recording medium 20 or its manufacturing process. The multilayer optical recording medium 20 or the bending of the laminated structure 14 of its manufacturing process.

(Conditions about the angle between stresses)

The first direction in which the direction of the component in the principal surface of the tensile stress caused by the external force is applied to the attached layered body 33 which is in the state of being laminated on the adhesive structure 31 (in this case) The embodiment is simply referred to as the "first direction". The second direction is the direction of the component in the principal surface of the tensile stress that the adhesive layer 32 has (in the present embodiment, it is simply referred to as the "second direction". The inter-stress angle R is 0° over 120°. In the following, the condition that satisfies the angle between the stresses is also referred to as "condition 1".

In order to satisfy the condition 1 as described above, it is possible to reduce the concentration of the stress remaining in the laminated structure by controlling the angle between the stresses, and it is possible to effectively prevent the residual stress caused by the direction of the principal surface of the laminated structure. The bending of the laminated structure of the multilayer optical recording medium or its manufacturing process.

In order to satisfy the condition, the external force is applied by the application process, and the manufacture of the optical recording medium 20 for reducing the occurrence of bending is realized.

Further, as will be described later, the first direction and the second direction may be defined by the method of imparting a force other than the tensile stress as the direction vector imparted to the external force of the attached layered body 33 (including the direction of the applied force). The state of the occurrence occurs. In this state, the inter-stress angle R of the condition 1 is the direction vector (the first direction) of the force applied to the layered body 33 and the farthest position of the substrate which is the farthest from the adhesive structure 31. The adhesion layer 32 of the unit laminated body on the side is given an angle formed by the direction vector (second direction) of the external force, and the inter-stress angle R of the condition 1 is defined.

The multilayer optical recording medium 20 or the laminated structure 14 of the manufacturing process thereof The magnitude of the residual stress in the direction of the principal surface can be measured by using X-ray diffraction, acoustic elasticity by ultrasonic waves, stress reduction by machining, etc., and measuring the skew occurring at this time. The means of knowing, and measuring the magnitude of residual stress. Further, in the present embodiment, it is apparent that, in actuality, even in the case where no residual stress is measured, the respective lamination processes are caused by the residual stress in the main surface direction of the laminated structure 14 due to the external force applied. Since the multilayer optical recording medium 20 is bent, it is possible to determine whether or not to reduce the concentration of residual stress by measuring the amount of bending of the multilayer optical recording medium 20 manufactured by the manufacturing method of the present embodiment.

The condition 1 is a condition in which the layered body 33 is placed in the state of being laminated on the adhesive structure 31. Therefore, the layered body 33 is attached to the adhesion structure 31 and the application process is performed and applied. The relationship between the time when the external structure is applied to the adhesive structure 31 is arbitrary. In other words, the external force applying system of the adhesive structure 31 by the application process may be before, during, and after the attachment process of the adhesive structure 31 to attach the laminated layer 33. Any one, and it is also possible to give an external force at a plurality or all of these timings.

The type of the external force to be applied is not particularly limited. However, since the laminated layer 33 is provided in the main surface direction and has a tensile stress, it is preferable to provide the tension to the layered body 33. An external force is formed by at least one of the pressing force, and it is more desirable to apply the process to impart both the external force tension and the pressing force. Specifically, the tension applied to the attached layered body 33 before or during the application of the attaching process, and the pressing force applied to the attached layered body 33 during or after the application of the attaching process are exemplified ( Specifically, proceed At the same time, the pressing portion thereof is moved to the main surface direction of the attached layered body 33. )Wait.

Further, it is preferable that the application process is applied to the surface side 33b opposite to the opposite surface 33a of the adhesive laminate 32 to which the layered body 33 is attached, and the external force is applied to the member to impart an external force to the attached layer. The shape of the layered body 33 is a process in which the layered body 33 is provided in a state of having tensile stress in the direction of the main surface.

The external force is not particularly limited as long as the effect of the present invention is obtained. However, it is preferable that the external force is 0.02 kgf/m or more in terms of the tension in the main surface direction (the same applies hereinafter). It is 0.04kgf/m or more. In a state where the external force is excessively high, the tensile stress of the layered body 33 is excessively high, and the state in which the layered body 33 is laminated may not be maintained. Therefore, the external force is preferably 400 kgf/m or less, more preferably 320 kgf/m or less.

If a specific example is shown with respect to the tension, the both end portions of at least one of the directions in the main surface of the attached layered body 33 are held so that the holding portions are separated from the direction and the attached layer The shape 33 is a method for imparting tension. This holding method is arbitrarily set, and is appropriately set by the relationship between the initial period of the stretching force and the start time of the stacking operation. For example, the holding portions of the layered body 33 can be held by using a holding means such as a clip, and the holding means can be separated to apply tension before the attachment process is carried out. Alternatively, tension can be imparted during the implementation of the attachment process. Specifically, a portion corresponding to an end portion of one side of the layered body 33 may be attached to the adhesive structure 31 such that the adhesive structure 31 is one of the holding means, and other holding means such as a clip is used. To keep the other side At the same time, the tension which is left by the portion attached to the adhesive structure 31 is given, and the remaining portion of the attached layered body 33 is not attached, and is attached to the adhesive structure 31.

In the case where a specific example is shown with respect to the pressing force, a method of applying a pressing force by pressing the laminated layer body 33 by using a cylindrical body such as a pressure roller is exemplified. That is, the method of imparting the pressing force during and/or after the attachment process is opposite to the opposite side of the opposite face 33a of the adhesive laminate 32 to which the layered body 33 is attached. The surface 33b (as will be described later, in the state in which the peeling material is attached to the surface 33b, on the opposite side to the opposite side of the facing side of the surface 33b of the peeling material), by the cylindrical shape The body (pressing roller) is pressed against the normal direction of the main surface, and at the same time, the cylindrical body (pressing roller) is rotated and moved. As a result, the layered body 33 is attached to the force in the direction in which the tubular body (pressing roll) moves in the forward direction (extrusion force).

In particular, the shape of the substrate 12 is bonded to the end portion of the substrate 12 when the rotating cylindrical body (pressing roller) is simultaneously moved in a state of, for example, a general optical disk substrate. Since the area of the layered body 33 to which the cylindrical body (pressing roll) is attached is small, the force applied to the attached layered body 33 is likely to increase. At this time, the vicinity of the end portion of the substrate 12 has a relatively high tensile stress.

(3) Direction control process

The direction control process sets the position of at least one side of the laminated layer 33 and the adhesive structure 31 so that the inter-stress angle R formed by the first direction and the second direction satisfies the process of the condition 1, as long as the condition 1 is achieved. The specific method is not particularly limited. In addition, the period of implementation of the direction control process The relationship with the period of starting the other processes (attaching process and applying process) constituting the stratification process is also arbitrary.

For example, a method in which the adhesive structure 31 can be rotated as a rotation axis in the normal direction of the main surface thereof and the attachment process is performed after the rotation of the adhesive structure 31 is used as a direction control process is exemplified.

If it is specifically described using FIG. 4(a) and FIG. 4(b), as shown in FIG. 4(a), the normal direction 36 of the main surface of the adhesive structure 31 is used (in FIG. 4(a). In the upper and lower directions, the base 41 and the adhesive structure 31 of the fixed substrate 12 are rotated together as a rotating shaft, and the second direction 38 is controlled to satisfy the condition 1 described above, and the direction control process is performed. Further, 37 indicates the first direction, and 38 indicates the second direction. After performing the direction control process as described above, as shown in FIG. 4(b), the attachment process of attaching the layered body 33 to the adhesive structure 31 and the application of the layered body 33 to the external force are performed. Apply the process. Specifically, the attached layered body 33 in the state in which the tension is given in the first direction 37 (that is, the state in which the application process is performed) is attached to the adhesive structure 31 (attaching process). By setting the first direction 37 and the second direction 38 in this manner, the condition 1 is satisfied.

In FIG. 4(a), the application process is performed before the attaching process, but is not limited thereto. The timing at which the external layer is applied to the layered body 33 is applied as the timing of the application process. If the adhesive structure 31 is rotated by the direction control process, it can be any timing (that is, the attachment process). Any one before, during, and after implementation). For example, as shown in FIG. 4(c), in the state where the application process is a process of applying an external force by pressurization using the pressurizing pressure roller 42, the application process is performed after the attachment process is performed. Add process.

As another specific example of the directional control process, the laminated layer body 33 can be rotated as a rotation axis in the normal direction of the main surface of the adhesive structure 31, and the layered body 33 is attached as a rotation. After the direction control process, the method of attaching the process is implemented. Specifically, as shown in FIG. 5(a), when the direction in which the external force is applied is the first direction 37, the normal direction of the main surface of the adhesive structure 31 (in the upper and lower directions of FIG. 5) is As the rotating shaft, the layered body 33 is attached and rotated, and the first direction 37 is controlled to perform the direction control process. As shown in FIG. 5( b ), after the first direction 37 and the second direction 38 satisfy the condition 1 , the attached layered body 33 is attached to the adhesive structure 31 . In this state, as shown in FIG. 5(b), the attached layered body 33 which is previously biased in the first direction 37 can be attached, and as shown in FIG. 5(c), pressurization can be used. The layered body 33 is press-bonded by the pressure roller 42 while being moved, and the pressing is applied to the layered body 33.

Further, in FIGS. 4 and 5, the thickness of the layered body 33 attached to the long rule and the thickness of the adhesive laminate 32 are different, but in reality, they have the same thickness. In addition, in FIG. 4 and FIG. 5, the unit laminated body 11 and the adhesive structure 31 of the adhesive structure 31 correspond to the shape of the board|substrate 12, However, It is not limited to this, and is demonstrated by the cutting process mentioned later. It is also possible that there is no shape corresponding to the substrate 12.

More specifically, a specific example of a method of setting the inter-stress angle R to satisfy the condition 1 in the direction control process will be described below.

(Setting method 1)

Each of the unit laminate 11 and the cover layer 13 (in the present embodiment, collectively referred to as "attached layered body") of the laminated structure 14 of the present embodiment is set to have an inter-stress angle R and satisfies the following relationship. In other words, the setting method 1 is a method of setting the inter-stress angle R in consideration of the position and the number of laminations in which the layered body is laminated.

The laminated layer i of the i-th layer is laminated with respect to the adhesive structure 31 (however, i is an integer of 2 to n, and the total number of layered bodies of the n-type laminated structure 14 is attached). The first direction of the direction of the component in the principal surface of the tensile stress is attached to the side of the substrate 12 which is laminated in the attached layered body closest to the closest position of the attached layered body i The inter-stress angle R1 in the second direction of the direction of the component in the principal surface of the tensile stress (i-1) satisfies the formula (I); R1 = 360° × m / n (I)

However, m is an integer of 1 or more.

By setting as described above, the first direction in which the direction of the component in the main surface of the tensile stress is applied is not overlapped with each other, and the dispersion is performed. By this, the concentration of the tensile stress remaining in the laminated structure 14 can be reduced, and the lamination of the multilayer optical recording medium or its manufacturing process caused by the residual stress in the direction of the principal surface of the laminated structure can be effectively prevented. The curvature of the structure. Further, as shown in the laminated structure 14 shown in Fig. 2(a), the layered body which is laminated between the substrate 12 and the attached layered body 11-1 which is closest to the substrate 12 is adhered as a whole. In the state of the agent layer 15, there is no set inter-stress angle R ₁ .

(Setting method 2)

In the state in which the unit laminate 11 has a hard layer, the tensile stress per unit layer 11 is greatly dependent on the tensile stress of the hard layer. Further, most of the state in which the cover layer 13 or the optical recording layer 1 also has a high tensile stress occurs. In other words, in the state where the unit laminate 11 has a hard layer, the inter-stress angle R is set by the setting method 2.

Then, the total thickness of the cover layer 13, the optical recording layer, and the hard layer of the laminated structure 14 is taken as the total thickness of the cover layer, the optical recording layer, and the hard layer including the first attached layered body. When B ₁ is the B ₂ and the total thickness of the cover layer, the optical recording layer, and the hard layer included in the second attached layered body closest to the closest position of the first attached layered body is B ₂ , The first direction in which the first layer direction of the tensile stress is in the first direction of the tensile stress is caused by the second direction in the direction of the main surface of the tensile stress which is the second additional layered body. The angle R ₂ can be set in the lamination process, and the inter-stress angle R is set to satisfy the following formula (II).

R ₂ =180°×[(B ₁ +B ₂ )/A]/2 (II)

In this state, the influence of the thickness of the hard layer on each of the attached layered bodies is considered. Therefore, the laminated structure 14 which is more likely to reduce the occurrence of bending is obtained.

In addition, when the relationship between the first attached layered body and the second attached layered body is applied to the adhesive laminated body 32 and the laminated layered body 33, the lamination by the attached laminated body 33 can be reduced. It is preferable that the residual stress of the laminated body of the laminated layered body 33 and the adhesive structure 31 which are laminated by the process is obtained.

(4) Cutting process with attached layered body

A cutting process in which the layered body 33 is provided to have a shape corresponding to the substrate 12 will be described. The relationship between the execution period of the cutting process and the execution period of the aforementioned lamination process is arbitrary. In the following, examples are made regarding the number of different forms of these implementation periods.

(4-1) The state of the stratification process after the process is cut off

In the present embodiment, as shown in FIG. 8, the layered body 33 is attached and cut into a shape corresponding to the substrate 12, and an attached layered body 60 having a desired shape is formed (cutting process). As shown in Fig. 4(c), the obtained laminated body 60 having a desired shape is laminated on the adhesive laminate 32 (layering process). In this state, there is also a possibility that the state of the multilayer optical recording medium 20 can be completed by performing a lamination process.

Here, a detailed description will be given with reference to Fig. 8 . FIG. 8 is a cross-sectional view conceptually showing a specific example of the attached layered body 60 corresponding to the shape of the substrate in advance. In Fig. 8(a), a plurality of the additional layered bodies 60 having the shape corresponding to the substrate 2 are cut in advance and provided on one side of the long-side peeling material 35. In Fig. 8(a), the surface on the side of the optical recording layer 1 is attached to the long-length peeling material 35. On the other hand, in Fig. 8(b), in the same manner as in the state of Fig. 8(a), a plurality of the attached layered bodies 60 which have been subjected to the cutting process in advance are provided on one side of the long-length peeling material 34. surface. In Fig. 8(b), a long-length peeling material 34 is attached to the surface of the adhesive layer 2 side. Other peeling materials may be attached to the surface opposite to the side of the peeling materials 34 and 35 on the long side of the layered body 60, and other peeling materials may not be attached. In the state in which other peeling materials are attached, the shape is arbitrary, and it can be peeled off like a long rule. The materials 34 and 35 are used as long pieces, and a material for peeling corresponding to the shape of the layered body 60 may be attached. The productivity of the lamination process of the present embodiment is improved by using such an attached layered body 60. In addition, the attached layered body 60 shown in FIG. 8 has a loop shape including a through hole in the thickness direction at the center portion of the main surface in accordance with a general optical disc shape.

(4-2) The state of the cutting process after the stratification process

Further, in the present embodiment, as shown in FIG. 4(b), FIG. 5 and the like, the laminated body 33 may be laminated on the adhesive layer 32 without the shape corresponding to the shape of the substrate 12. After the lamination process, a cutting process in which the layered body 33 is laminated on the adhesive structure 31 and cut into a shape corresponding to the substrate 12 is performed.

At this time, the adhesive laminate 32 has a shape corresponding to the substrate 12, and only the layered body 33 can be processed as a cutting process, and the attached layered body 33 and the adhesive laminate 32 can also be formed. Cut the processed object. In the latter state, in the cutting process, the layered body 33 and the adhesive layered body 32 are simultaneously cut and formed to have a shape corresponding to the substrate 12.

In the state in which the layered body 33 and the adhesive layered body 32 are simultaneously cut, the state of the unit laminate is also present between the adhesive layered body 32 and the substrate 12 (as a specific example, as shown in FIG. 3) The state in which the unit laminates 11-1 and 11-2 are present under the unit laminate 11-3 of the adhesive laminate 32 is formed.), these unit laminates (the unit laminate 11 of Fig. 3) -1 and 11-2) can also be cut at the same time. At this time, in a state in which the cover layer body 33 is also included in the cover layer 13, the cover layer 13 may be simultaneously cut. By doing this, after the stratification process, the cutting process can be performed. On the other hand, the cutting process is performed once, and the layered body 33, the adhesive structure 31, the unit laminated body 11, and the cover layer 13 are simultaneously cut.

The embodiments described above are described in order to facilitate the understanding of the present invention and are not intended to limit the present invention. Therefore, the various elements disclosed in the above-described embodiments are intended to encompass all of the design changes and equivalents of the technical scope of the invention.

[Examples]

In the following, the present invention will be more specifically described by way of examples, but the scope of the invention is not limited to the examples and the like. Fig. 6 is a schematic plan view of the multilayer optical recording medium of the first embodiment viewed from the upper side (the surface side of the substrate on which the substrate is placed), and shows the first direction and the second direction of each of the lamination processes.

[Example 1] (1) Formation of optical recording layer

100 parts by mass of polymethyl methacrylate, 10 parts by mass of 1,3,3-trimethylindanyl-6'-nitrochroman, 500 masses as a photochromic material A portion of the ethyl acetate and 490 parts by mass of toluene were prepared to prepare a coating liquid having a solid concentration of 10% by mass.

The coating liquid was applied to the single surface of a polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., PET 50A4100) having a thickness of 50 μm as the material for the first peeling, by a gravure coating method. At ° C, drying was performed for 1 minute to form an optical recording layer having a thickness of 2 μm.

(2) Formation of adhesive layer

30 parts by mass of n-butyl acrylate polymer (BA; Mw = 500,000), dissolved in 100 parts by mass of ethyl acetate to prepare a coating liquid having a solid concentration of 30% by mass.

a peeling surface of a peeling material which is formed by providing an oxime release layer on one side of a polyethylene terephthalate film (manufactured by Toray Co., Ltd., PET38T-100) having a thickness of 38 μm as a material for the second peeling material, The coating liquid was applied by a knife coater and heated at 90 ° C for 1 minute ^. It was dried to form an adhesive layer having a thickness of 8 μm.

(3) Production of attached layered body

By combining the adhesive layer formed in the above (2) and the optical recording layer formed in the above (1), press-bonding is performed by two rubber press rolls, and the stacking is performed in this order. A layered body having a long length of a unit laminate composed of a material for peeling, an optical recording layer, an adhesive layer, and a second peeling material is produced.

(4) Production of adhesive structure

A substrate made of polycarbonate (manufactured by Teijin Chemicals Co., Ltd.) having a thickness of 1 mm in a disk shape of 5 mm is clamped on a base having a rotating mechanism as a rotating shaft in a vertical direction, and one side is exposed upward. surface. On the exposed surface of the substrate, the same material as the coating liquid of the above (2) is used for coating ^. It was dried to provide an adhesive layer having a thickness of 40 μm. Then, the attached layered body of the long length obtained in the above (3) is conveyed in a predetermined direction, and the first peeling material is peeled off to expose the side of one side of the optical recording layer. Then, the attached layered body is attached to the substrate, and is pressed by a rubber press roll (5 kgf/m in terms of the tension in the main surface direction), and is opposite to the opposite side of the substrate on which the layered body is attached. And simultaneously, moving on one side of the in-plane direction, and bonding the exposed surface opposite to the opposite side of the substrate of the adhesive layer on the substrate and the surface of the optical recording layer, so that the laminated layer is laminated on the substrate . In this manner, an adhesive structure having a structure in which a substrate, an adhesive layer, and a unit laminate are laminated in this order is obtained. Further, at this point of time, the second peeling material is attached to the farthest position surface of the substrate farthest from the adhesive structure. Next, the attached layered body of the long rule is cut so that the adhesive laminate has a slightly larger shape slightly larger than the 5-inch disc shape.

(5) The first layer process

Further, in the first embodiment, the inter-stress angle set using the above formula (I) of the above-described setting method 1 is set. In order to make the inter-stress angle R 45°, the base of the provided adhesive structure is rotated by 45° in the counterclockwise direction as viewed from the upper side. That is, the second direction 38 is controlled. Next, the second peeling material attached to the uppermost surface of the adhesive structure is peeled off to expose the side of one side of the adhesive layer. On the other hand, as described above, the attached layered body of the long length to be manufactured is conveyed in a predetermined direction, and the first peeling material is peeled off to expose the side of one side of the optical recording layer. Next, the surface of the adhesive layer on which the adhesive structure is exposed is exposed and the surface of the recording layer on which the laminated layer is attached is exposed, and the laminated structure is bonded to the adhesive structure. Then, the surface of the second release material side of the layered body is pressed by a rubber press roll, and the layered body and the adhesive structure are press-fitted by moving one side of the in-plane direction. A laminate in which a layered body is laminated in an adhesive structure is obtained. Here, the moving direction of the rubber pressure roller is the same as (2) above.

As a result, the first direction (37-1 in FIG. 6) of the main in-plane direction of the tensile stress which is provided by the external force applied to the layered body by the first lamination process is relative to the layer. Adhesive laminate of the integrated process The second direction in the direction of the main surface of the force (38-1 in Fig. 6) is viewed from the upper side (the surface side of the substrate on which the base is placed), and becomes an angle of 45° in the clockwise direction. In this manner, the inter-stress angle R of the laminated layered body of the lamination process with respect to the adhesive laminate is 45° (the clockwise direction becomes a positive value when viewed from above). Next, the attached layered body of the long rule is cut so that the laminated body has a slightly larger shape slightly larger than the 5-inch disc shape.

A series of processes consisting of the rotation of the base (the direction control process), the attaching of the layered body and the adhesive structure (attachment process), and the lamination (application process) of the layered body are described. For the first layer of the process.

(6) 2nd to 6th stacking process

By the implementation of the first lamination process, a laminate in which the adhesive layer and the two-layer unit laminate are arranged in this order on the substrate is obtained. Further, the second peeling material is attached to the farthest position surface of the substrate farthest from the laminate. Then, in order to make the inter-stress angle R 45°, after the base is viewed from the upper side and rotated 45° in the counterclockwise direction, the laminated body is used as the adhesive structure. The second peeling material attached to the adhesive structure is the same as the first layering process, and the attached layered body is conveyed along a predetermined direction, and the first peeling material attached to the attached layered body is peeled off. In the adhesive structure, a layered body is attached and attached, and press-bonding by pressing of a press roll is performed. This series of processes, referred to as the second layering process, will be followed by the stratification process, referred to as the third stack process and the fourth stack process. In addition, even if it is about any one of the lamination processes, after the end, the attached layered body of the long rule is cut.

The result of the second layer process is viewed from the top side and becomes According to the first direction of the in-plane direction of the tensile stress (37-2 in FIG. 6) and the adhesion layer of the second lamination process, which are given to the external layer of the second lamination process, The inter-stress angle R between the second direction (38-2 in Fig. 6) of the main surface in the tensile stress is 45°.

The third layer process is continuously performed to the sixth layer process in the same manner as the second layer process. As a result, the main in-plane direction (37-1 in FIG. 6) of the tensile stress which is laminated in the unit stacking process in the first layering process, as viewed from the upper side, is given to the fifth layer. The angle of the first direction (37-5 in Fig. 6) of the direction in which the tensile force is applied to the main surface of the tensile stress is 180°. In addition, the first direction (37-6 in FIG. 6) of the main in-plane direction of the tensile stress which is provided by the force applied to the external layered body of the sixth layering process is the closest to the closest to the substrate. The angle of the main in-plane direction of the tensile stress (the 37-1 in Fig. 6) of the unit laminate of the position is 270°. Further, in Fig. 6, the first direction (37-4 to 37-7) from the fourth layering process to the seventh layering process is displayed from the viewpoint of easy visibility, and the direction is not displayed ( The arrow is omitted, but the first direction shown in 38-1, 37-1 to 37-3, and the direction parallel to the direction are opposite.

(7) 7th layer process

It consists of an adhesive structure (a laminated substrate, an adhesive layer, and a 7-layer unit laminate) obtained by the sixth layering process, and is attached to the surface farthest from the substrate. (2) The material for peeling is used to peel off the second peeling material, and the surface of the adhesive layer of the unit laminate laminated in the sixth layering process is exposed. On the other hand, a polycarbonate film having a thickness of 78 μm is prepared. On the other side, a cover layer composed of a corona film (Pureace made by Teijin Co., Ltd., Pureace) was applied as a layered body. After the adhesive laminate is rotated in the counterclockwise direction by 45° from the upper side, the exposed surface of the adhesive structure is attached to the adhesive structure, and the exposed surface of the adhesive layer and the cover layer are bonded to the adhesive structure. The surface of corona treatment. At this time, no special tension is imparted to the cover layer. In the following, press-bonding is performed by pressurization of the same press roll which is the same as the first lamination process. As a result, the main in-plane direction (38-1 in Fig. 6) of the tensile stress which is present in the unit laminated body closest to the closest position of the substrate is relative to the stretching which is based on the force applied to the covering layer. The angle of the first direction (37-7 in Fig. 6) of the direction of the main surface of the stress is -45.

(8) cutting process

By the above-described process, a laminated structure composed of a substrate, an adhesive layer, a seven-layer unit laminate, and a cover layer in this order is obtained. The laminated structure was subjected to punching and cut into a disc shape of 5 inches.

As a result, the unit laminate of the seven layers and the outer diameter of the cover layer were collectively cut to obtain a multilayer optical recording medium.

In the multilayer optical recording medium, the total number n of the unit laminated body and the covering layer of the laminated structure is 8, and each of the first directions is 45° with respect to the inter-stress angle R in the second direction. Therefore, the above formula (I) is satisfied. ).

[Embodiment 2] (1) Formation of optical recording layer

Mix 100 parts by mass of polymethyl methacrylate, 10 mass a 1,3,3-trimethylindanyl-6'-nitrochroman, 500 parts by mass of ethyl acetate and 490 parts by mass of toluene as a photochromic material to prepare a solid component A coating liquid having a concentration of 10% by mass.

The coating liquid was applied to the single surface of a polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., PET 50A4100) having a thickness of 50 μm as the material for the first peeling, by a gravure coating method. At ° C, drying was performed for 1 minute to form an optical recording layer having a thickness of 2 μm.

(2) Formation of adhesive layer

30 parts by mass of n-butyl acrylate polymer (BA; Mw = 500,000) was dissolved in 100 parts by mass of ethyl acetate to prepare a coating liquid having a solid concentration of 30% by mass.

a peeling surface of a peeling material which is formed by providing an oxime release layer on one side of a polyethylene terephthalate film (manufactured by Toray Co., Ltd., PET38T-100) having a thickness of 38 μm as a material for the second peeling material, The coating liquid was applied by a knife coater and heated at 90 ° C for 1 minute ^. It was dried to form an adhesive layer having a thickness of 8 μm.

(3) Formation of coating liquid for energy ray hardening type adhesive

30 parts by weight of an ethyl acetate solution containing 30% by weight of an n-butyl/acrylic acid copolymer of acrylic acid (composition weight ratio of 80/20) in a solid content concentration, relative to 100 equivalents of the acrylic acid component in the copolymer 2-Methyl propylene methoxyethyl isocyanate was reacted under a nitrogen atmosphere for 48 hours to obtain an average side chain introduction ratio of methacryl oxime group which is an energy hardening functional group of 9.2 mol% and a weight average A solution (A) of an energy hardening type copolymer having a molecular weight of about 850,000.

To the low energy (2-hydroxy-2-methyl-1-[4-(1-propenyl)phenyl) as a photopolymerization initiator, relative to 100 parts by weight of the energy-hardening copolymer solution (A) 3.0 parts by weight of propane) (product name "ESCURE KIP150" manufactured by Lamberti Spa Co., Ltd.) and 1.0 part by weight of an isocyanate crosslinking agent (manufactured by Toyo Ink Co., Ltd., trade name "Oribain BPS-8515") as a crosslinking agent A coating liquid for modulating an energy ray-curable adhesive.

(4) Production of unit laminate

In the optical recording layer formed in the above (1), the coating liquid prepared by the above (3) is applied by a doctor blade applicator, and heated at 90 ° C for 1 minute ^. It is dried to form a layer composed of an energy ray-curable adhesive (also referred to as "unhardened layer" in the present specification). The thickness of the uncured layer is 20 μm.

Next, the coating liquid for the optical recording layer prepared in the above (1) is applied by a doctor applicator on the exposed side opposite to the opposite side of the optical recording layer of the uncured layer, at 90 ° C. Drying was performed for 1 minute to form an optical recording layer having a thickness of 2 μm.

Next, by combining the optical recording layer thus obtained and the adhesive layer formed in the above (2), press-bonding is performed by two rubber press rolls, and the laminated optical recording layer and the adhesive layer are included. The laminate of the long-length unit of the unit laminate is composed.

In the laminate produced in this manner, a high-pressure mercury lamp (manufactured by EYE GRAPHICS Co., Ltd., a high-pressure mercury lamp) was used, and ultraviolet rays of a light amount of 500 mJ/cm ^{2 were} irradiated to cure the uncured layer. The laminated layered body 50 composed of the first peeling material 51, the optical recording layer 52, the support layer 53, the optical recording layer 54, the adhesive layer 55, and the second peeling material 56 is laminated in this order. .

(5) Setting the angle between stresses

In the present embodiment, a corrugated film (Pureace made by Teijin Co., Ltd., manufactured by Teijin Co., Ltd.) was used on the side of one side of the polycarbonate film having a thickness of 78 μm. A cover layer composed of a plastic film. Therefore, the total thickness of the hard layers included in all of the five attached layered bodies and the cover layer is 198 μm (= (2+20 + 2) × 5 + 78). In addition, the total thickness of the hard layer of each of the laminated layer bodies which are included in the laminated structure produced by using these laminated layered bodies is 24 μm in a state in which the laminated layered body is composed of a unit laminated body (= 2+20+2) is 78 μm in a state in which the layered body is composed of a coating layer.

Therefore, the second to fifth unit laminates are stacked between any of the first to fourth unit laminates of the respective lower layers by using the above formula (II) of the above-described setting method 2. As a result of the inter-stress angle, the angle between the stresses from the second to fifth unit laminates was 21.8° (= (180 × 24 + 24) / 2 / 198)). Similarly, the angle between stresses of the cover layer and the fifth unit laminate is 46.4° = (180 × (78 + 24) / 2 / 198)).

(6) Production of laminated structure

Using the inter-stress angle set by the above (5), the rotation angle of the base is set in the same manner as in the first embodiment, and the second to sixth lamination processes are performed to form a laminated structure, and finally, the cutting is performed. The process is interrupted to produce a multilayer optical recording medium.

[Example 3] (1) Production of adhesive structure

A substrate made of polycarbonate (manufactured by Teijin Chemicals Co., Ltd.) having a thickness of 1 mm in a disk shape of 5 mm is clamped on a base having a rotating mechanism as a rotating shaft in a vertical direction, and one side is exposed upward. surface. The second peeling material was peeled off by exposing the surface of one side of the adhesive layer, and the surface was attached to the substrate, and the rubber was pressed by a rubber press roll, starting from the layered body attached to the long ruler produced in Example 1. The pressure (5 kgf/m in terms of the tension in the direction of the main surface) is opposite to the surface on the opposite side of the substrate on which the layered body is attached, and is moved to one side of the in-plane direction, so that the layered body is laminated and laminated. On the substrate. In this way, an adhesive structure in which the substrate and the layered body as the adhesive laminate are laminated in this order are obtained. Further, the first peeling material which is the farthest position from the substrate of the adhesive structure is peeled off. Next, the attached layered body of the long rule is cut so that the adhesive laminate has a slightly larger shape slightly larger than the 5-inch disc shape.

(2) The first layer process

Next, in the same manner as in the first embodiment, in order to make the inter-stress angle R 45°, the base of the adhesive structure obtained in the foregoing description is rotated by 45° in the counterclockwise direction. Next, as described above, the attached layered body of the long length to be manufactured is conveyed in a predetermined direction, and the second peeling material is peeled off to expose the side of one side of the adhesive layer. Next, the surface of the optical recording layer on which the adhesive structure is exposed is exposed and the surface of the adhesive layer on which the layered body is attached is exposed, and the laminated structure is bonded to the adhesive structure. Then, the surface of the first release material side of the layered body is pressed by a rubber press roll, and the layered body and the adhesive structure are press-fitted by moving one side of the in-plane direction. A laminate in which a layered body is laminated in an adhesive structure is obtained. Here, the aforementioned rubber pressure roller The moving direction is the same as the moving direction of the rubber pressure roller at the time of fabricating the aforementioned adhesive structure. By the implementation of the first layering process, a laminate in which two unit unit layers are arranged in this order on the substrate is obtained.

Next, the first peeling material which is farthest from the surface of the substrate of the adhesive structure is peeled off. Then, the attached layered body of the long rule is cut so that the attached layered body after cutting has a shape larger than the shape of the disk.

(3) 2nd stack process to 6th stack process

Next, the attached layered body from the second layering process to the sixth layering process and the long length after each layering process is cut in the same manner as the first layering process.

(4) 7th layer process

Using the same material as the coating liquid of the above-mentioned adhesive layer, the coating liquid was applied to the peeling surface of the second peeling material by a knife coater, and heated at 90 ° C for 1 minute ^. It was dried to form an adhesive layer having a thickness of 40 μm. On the other hand, a cover layer composed of a plastic film (Pureace made by Teijin Co., Ltd.) which is a polycarbonate film having a thickness of 78 μm and which is subjected to corona treatment on one side is prepared. The surface on the side of the adhesive layer of the laminate composed of the pressure-sensitive adhesive layer and the second release material and the surface on which the prepared cover layer was subjected to corona treatment were attached. Then, the laminated body obtained by the attachment is press-bonded by two rubber press rolls to obtain the attached layered body composed of the adhesive layer and the cover layer, and the second peeling is attached. A layer of material.

Then, the adhesive structure (the laminated substrate and the unit laminate of 7 layers) which are obtained by the above-described sixth stacking process are formed, and the first peeling is attached to the surface farthest from the substrate. Using the material.), to peel off the first peeling material, The surface on the side of the optical recording layer of the unit laminate laminated in the sixth laminate process is exposed. Next, the adhesive laminate 45° was rotated in the counterclockwise direction from the upper side.

Then, the second peeling material attached to the laminated body including the cover layer is peeled off, and the adhesive layer is bonded to the adhesive structure, and the exposed adhesive layer side surface is bonded to the exposed laminated body. And the farthest position of the substrate farthest from the adhesive structure. At this time, no special tension is imparted to the attached laminate including the cover layer. In the following, the first laminate process is performed on the surface of the cover layer side of the laminated body to which the adhesive structure is laminated.

(5) cutting process

By the above process, a laminated structure composed of a substrate, a 7-layer unit laminate, an adhesive layer, and a cover layer in this order is obtained. This laminated structure was punched and cut into a disk shape of 5 inches to obtain a multilayer optical recording medium.

The multilayer optical recording medium produced by the above manufacturing method is also the same as the multilayer optical recording medium of the first embodiment, and the inter-stress angle set using the above formula (I) of the setting method 1 is set. That is, the total number n of the unit laminated body and the covering layer of the laminated structure is 8, and the inter-stress angle R ₁ between each is 45°.

[Example 4]

A multilayer optical recording medium was produced in the same manner as in Example 2 except that the cutting process was carried out before the lamination process. Specifically, the first peeling material in which the layered body is attached is peeled off from the exposed light recording layer side, and only the optical recording layer, the support layer, and the optical recording layer are cut into 5 inches. The shape of the disc. By this, the cutting process is performed in advance to form an attached layered body having a 5-inch disc shape (having a structure in which the optical recording layer, the support layer, and the optical recording layer are laminated in this order), and is provided for the second peeling. A layered body is attached to one side of the material. Using the obtained layered body, a lamination process was carried out by the same inter-stress angle as in Example 2, and a laminated structure was produced to produce a multilayer optical recording medium.

[Comparative Example 1]

A multilayer optical recording medium was produced by performing the same manufacturing method as in Example 1 except that the angle between the stresses was not set, and the lamination process was performed by the same inter-stress angle. That is to say, the angle R between stresses is 0°.

(Test Example 1) Evaluation of bending

With respect to the multilayer optical recording medium of the example and the multilayer optical recording medium of the comparative example, the inclination of the disc was confirmed by a film thickness measuring instrument (Core9930a manufactured by Cores). If the radiation tilt is ±6° and the tangential tilt is ±3°, it is judged that no bending has occurred, and if it is not satisfied, it is judged that the bending has occurred.

The results of the evaluation are shown in Table 1.

[Industrial Availability]

The present invention is useful for producing a multilayer optical recording medium having less curvature.

11-1, 11-2, 11-3, 11-4‧‧‧ unit layer

12‧‧‧Substrate

31‧‧‧Adhesive structures

32‧‧‧Adhesive laminate

32a‧‧‧ opposite to the opposite side of the substrate 12 of the adhesive laminate 32

33‧‧‧With layered body

33a‧‧‧ facing the side of the adhesive laminate 32 of the unit laminate 11-4

33b‧‧‧ opposite to the opposite side of the face 33a of the unit laminate 11-4

34, 35‧‧‧ peeling materials

Claims (11)

A method of manufacturing a multilayer optical recording medium, wherein a unit laminate including at least an adhesive layer and an optical recording layer is laminated on a side of one side of a substrate and is to be laminated on a farthest side farthest from the substrate The laminated structure comprising the unit layer formed by forming the coating layer, comprising: the substrate comprising the adhesive structure including the substrate and the at least one unit laminate; a layered body selected from the group consisting of the unit laminate and the cover layer and the group of the laminates on the side of the adhesive layered body of the unit laminate on the farthest position side And at the same time, a lamination process for laminating the attached layered body of the adhesive structure to have a tensile stress; the lamination process includes attaching the attached layered body to the adhesive structure a process for attaching a body; an application process for applying an external force to the layered body; and controlling a direction in which the external layer is applied to the layered body by the application process To the control process, the direction control process controls the external force to be applied to the direction in which the layered body is attached, so that the tensile stress is caused by the external force of the attached layered body laminated on the adhesive structure. The first direction of the direction of the component in the main surface is equal to or less than 120° with respect to the inter-stress angle R in the second direction which is the direction of the component in the main surface of the tensile stress of the adhesive layer. . The method for manufacturing a multilayer optical recording medium according to the first aspect of the invention, wherein the application process is before, during, and after the implementation of the attaching process At least one of the above-described attached layered bodies is provided with a process of forming an external force by at least one of tension and pressing force. The method of manufacturing a multilayer optical recording medium according to the second aspect of the invention, wherein the application process is on a side opposite to a side opposite to a facing surface of the adhesive layered body of the attached layered body. The external force is applied to the member to impart an external force, and the attached layered body is subjected to a process of having a tensile stress in the direction of the main surface. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the adhesive structure system is rotatable as a rotation axis in a normal direction of a main surface thereof as the directional control process After the rotation of the adhesive structure, the attachment process is performed. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the attached layered system is rotatable as a rotation axis in a normal direction of a main surface of the adhesive structure. As the direction control process, after the above-described attached layered body is rotated, the above-described attaching process is performed. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the unit laminated system includes a hard layer having a layer having a glass transition temperature Tg of 25 ° C or higher. The method for producing a multilayer optical recording medium according to any one of the first to third aspects of the present invention, wherein a material for peeling off is laminated on at least one side of the layered body, and the layered body is peeled off from the layered body The peeling material exposes a surface of one side of the layered body, and the surface is opposite to the surface of the substrate opposite to the substrate of the adhesive layer A layered body is attached and attached to the above-mentioned adhesive structure. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the adhesive structure system laminates a material for peeling off from the surface on the side of the adhesive laminate, and the adhesive structure is The peeling material is peeled off, and the surface of one side of the adhesive laminate is exposed, and the surface of one side of the layered body is bonded to the surface, and the attached layered body is attached to the adhesive structure. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the layering process is performed in advance, and the attached layered body having a shape corresponding to the substrate is formed in advance , laminated on the aforementioned adhesive structure. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, further comprising: a cutting process for cutting the attached layered body to have a shape corresponding to the substrate. The method for producing a multilayer optical recording medium according to any one of claims 1 to 3, wherein the attaching process transports the attached layered body of a long length in a predetermined direction and attaches to the adhesive structure Attachment process.