WO2020195443A1

WO2020195443A1 - Production method for layered product

Info

Publication number: WO2020195443A1
Application number: PCT/JP2020/007298
Authority: WO
Inventors: 武春豊島; 利之小材
Original assignee: 信越化学工業株式会社
Priority date: 2019-03-25
Filing date: 2020-02-25
Publication date: 2020-10-01
Also published as: JP7111041B2; JP2020158548A; TW202100367A

Abstract

This production method for a layered product including a substrate, and an adhesive layer stacked on the substrate, wherein the adhesive layer is cured and formed by irradiating a composition containing components (A)-(C) with light having a peak wavelength of 380-420 nm. This method enables production of the layered product without inhibition of the curing by an adherend such as a polarizing plate even when the curing of the adhesive layer containing a photocurable silicone composition is performed at room temperature. (A) A polysiloxane (1): (R¹R² ₂SiO_1/2)_a(R² ₃SiO_1/2)_2-a(Ar₂SiO_2/2)_b(R² ₂SiO_2/2)_c {R¹ represents alkenyl, R² represents alkyl, Ar represents aryl, 'a' represents 0.3-2, b represents 0-100, c represents 1-1,000, and b/(b+c) = 0 to 0.7 is satisfied}. (B) A hydrogen polysiloxane (2) having at least two SiH bonds per molecule (2): R³ _dH_eSiO_[(4-d-e)/2] (R³ represents a monovalent hydrocarbon group, except for a C=C group, and d and e satisfy 0.7≤d≤2.5, 0.01≤e≤1.0, and 0.8≤d+e≤2.7). (C) A platinum compound having at least one of a β-diketonate group, a β-ketoesterate group, and a 1,3-diesterate group as a ligand

Description

Method of manufacturing a laminate

The present invention relates to a method for producing a laminate, and more specifically, to a method for producing a laminate having an adhesive layer made of a cured product of a photocurable silicone composition.

Electronic devices such as displays and touch panels that have image display capability generally include protective cover panels made of highly transparent resin such as acrylic or polycarbonate or glass, and polarizing plates and image display elements. It has an image display unit provided on the substrate.
An optical transparent resin layer is often arranged between the cover panel and the image display unit in order to improve visibility and mechanical strength.

As the optical transparent resin layer, an ultraviolet addition-curable transparent silicone adhesive composition has been proposed (Patent Document 1). Since the curing reaction of this adhesive composition by the platinum catalyst gradually proceeds with the irradiation of ultraviolet rays, the adhesive composition is applied on the polarizing plate of the image display portion, and the cover panel is attached after the irradiation with ultraviolet rays. A processing process can be adopted. As a result, the above-mentioned integrated molding method has the advantages that it can be used in places (dark areas) that are not irradiated with ultraviolet rays, and that a cover panel having an ultraviolet absorber can also be used to impart weather resistance. can get.

On the other hand, when the polarizing plate and the liquid resin are in contact with each other and irradiated with ultraviolet rays having a peak wavelength of 365 nm, which is generally used for ultraviolet curing, the curing of the resin may be delayed. It is considered that this phenomenon is because the curing inhibitor generated from the polarizing plate by the irradiation of ultraviolet rays inhibits the activity of the platinum catalyst. When this phenomenon occurs, the resin is not sufficiently cured on the polarizing plate, and as a result, the adhesive force and the adhesive force are lowered, and the reliability of the device is impaired.
In such a case, it becomes necessary to add a temperature raising process using a heating facility to ensure curability, or to extend the standing time until curing, which may reduce mass productivity and heat. There is a concern that the member may warp or the resin may deteriorate due to expansion and contraction. Moreover, since the curing behavior changes depending on the type of the polarizing plate, there is also a problem that the manufacturing process must be reviewed every time the polarizing plate is changed.

JP-A-2015-10752

The present invention has been made in view of the above circumstances, and even when the adhesive layer made of a photocurable silicone composition is cured at room temperature, it is not hindered by the adherend such as a polarizing plate. It is an object of the present invention to provide a method for producing a laminate.

As a result of diligent studies to solve the above problems, the present inventors irradiate a silicone composition containing a predetermined organopolysiloxane with light of a specific wavelength and cure it to form an adhesive layer at room temperature. The present invention has been completed by finding that the adhesive layer is rapidly cured on the polarizing plate even when the curing is performed with.

That is, the present invention
1. 1. A method for producing a laminated body including a first base material and an adhesive layer laminated on the first base material, wherein the adhesive layer contains the following components (A) to (C). A method for producing a laminate, which comprises irradiating a photocurable silicone composition with light having a peak wavelength of 380 to 420 nm and curing the photocurable silicone composition.
(A) Linear organopolysiloxane represented by the following average formula (1): 100 parts by mass (R ¹ R ² ₂ SiO _1/2 ) _a (R ² ₃ SiO _1/2 ) _2-a (Ar ₂₎ SiO _2/2 ) _b (R ² ₂ SiO _2/2 ) _c (1)
{In the formula, R ¹ independently represents a substituted or unsubstituted alkenyl group, R ² independently represents a substituted or unsubstituted alkyl group, and Ar independently represents a substituted or unsubstituted alkyl group. It represents a substituted or unsubstituted aryl group, a represents a number of 0.3 to 2, b is 0 to 100, c is 1 to 1,000, and b / (b + c) = 0 to 0. . Represents a number that satisfies 7. }
(B) represented by the following average compositional formula (2), organohydrogenpolysiloxane having at least two Si-H bonds in one molecule: 1 to 200 parts by weight ^{_{_{_{R 3 d H e SiO [(}}}} 4- _{de) / 2]} (2)
(In the formula, R ³ independently represents a substituted or unsubstituted monovalent hydrocarbon group excluding the aliphatic unsaturated hydrocarbon group, and d and e are 0.7 ≦ d ≦ 2.5, respectively. It represents a number that satisfies 0.01 ≦ e ≦ 1.0 and 0.8 ≦ d + e ≦ 2.7.)
(C) A platinum compound having at least one of a β-diketonato group, a β-ketoesterate group, and a 1,3-diesterate group as a ligand. A method for producing a laminate of 1 in which the component (C) is bisacetylacetonato platinum (II).
3. 3. (I) A coating step of applying the photocurable silicone composition to the surface of the first substrate, and
(Ii) A light irradiation step of irradiating a photocurable silicone composition with light having a peak wavelength of 380 to 420 nm, and
(Iii) A curing step of curing a photocurable silicone composition to form an adhesive layer,
(Iv) Laminating a second base material on a photocurable silicone composition or an adhesive layer, and laminating the first and second base materials via the adhesive composition or the adhesive layer. A method for producing a laminate of 1 or 2 including steps,
4. 3. A method for producing a laminate of 3, wherein the curing step is performed at 5 to 35 ° C.
5. A method for producing a laminate of 3 or 4 in which the second base material is a polarizing plate or a polarizing film.
6. The method for producing a laminate according to any one of 1 to 5, wherein the first base material is a polarizing plate or a polarizing film.
7. The method for producing a laminate according to any one of 1 to 6, wherein the peak wavelength of light is 405 nm.
8. Provided is a method for manufacturing a laminate according to any one of 1 to 7, wherein the laminate is an image display device.

According to the method for producing a laminate of the present invention, the photocurable silicone composition cures rapidly even at room temperature of about 25 ° C. regardless of the type of polarizing plate with which it comes into contact. The manufacturing method of the present invention having such characteristics can be suitably used as a bonding method for image display devices such as touch panels and displays.

Hereinafter, the present invention will be specifically described.
The method for producing a laminate according to the present invention is a method for producing a laminate including a first base material and an adhesive layer laminated on the first base material, wherein the adhesive layer is formed as described above ( It is characterized in that a photocurable silicone composition containing the components A) to (C) is irradiated with light having a peak wavelength of 380 to 420 nm and cured to be formed.

[Photo-curable silicone adhesive composition]
Each component constituting the photocurable silicone adhesive composition used in the present invention will be described.
[1] Component (A) The component (A) in the photocurable silicone composition used in the present invention is a linear organopolysiloxane represented by the following average formula (1).
(R ¹ R ² ₂ SiO _1/2 ) _a (R ² ₃ SiO _1/2 ) _2-a (Ar ₂ SiO _2/2 ) _b (R ² ₂ SiO _2/2 ) _c (1)

In formula (1), R ¹ independently represents a substituted or unsubstituted alkenyl group.
The alkenyl group is not particularly limited and may be linear, branched or cyclic, but those having 2 to 20 carbon atoms are preferable, those having 2 to 10 carbon atoms are more preferable, and carbon atoms are more preferable. Those having the numbers 2 to 6 are even more preferable.
Specific examples of the alkenyl group include vinyl, allyl, butenyl, pentenyl, hexenyl group and the like, but the vinyl group is preferable.
Further, a part or all of the hydrogen atom of the alkenyl group may be substituted with a halogen atom such as F, Cl, Br, a cyano group or the like.

R ² independently represents a substituted or unsubstituted alkyl group.
The alkyl group is not particularly limited and may be linear, branched or cyclic, but those having 1 to 20 carbon atoms are preferable, those having 1 to 10 carbon atoms are more preferable, and carbon atoms are more preferable. Those having the numbers 1 to 5 are even more preferable.
Specific examples of the alkyl group include linear or branched alkyl groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, n-pentyl, n-hexyl and n-heptyl groups; cyclohexyl groups and the like. Cyclic alkyl groups and the like can be mentioned.
Further, a part or all of the hydrogen atom of the above alkyl group may be substituted with a halogen atom such as F, Cl, Br, a cyano group or the like, and specific examples of such a group include chloromethyl and 3 -Halogen-substituted alkyl groups such as chloropropyl and 3,3,3-trifluoropropyl groups can be mentioned.
Among these, a methyl group is preferable from the viewpoint of heat resistance.

Ar represents an independently substituted or unsubstituted aryl group.
The aryl group is not particularly limited, but preferably has 6 to 20 carbon atoms, and more preferably 6 to 10 carbon atoms.
Specific examples of the aryl group include phenyl, naphthyl, trill, xsilyl, mesitylene and the like.
Further, a part or all of the hydrogen atom of the aryl group may be substituted with a halogen atom such as F, Cl, Br, a cyano group or the like, and specific examples of such a group include a chlorophenyl group or the like. Can be mentioned.
Of these, a phenyl group is preferable.

In the above formula (1), a represents a number of 0.3 to 2. If a is less than 0.3, the content of R ¹ is low, so that there is a risk of bleeding out of uncrosslinked components and the composition becoming too soft.
b is a number from 0 to 100, but a number from 0 to 50 is preferable. If b is larger than 100, the viscosity may become too high.
c is a number of 1 to 1,000, preferably a number of 1 to 500, and more preferably a number of 100 to 300. If c is less than 1, the cured product may become too hard, and if it is more than 1,000, the viscosity may become too high.
b / (b + c) is 0 to 0.7, but 0 to 0.3 is preferable. If b / (b + c) is larger than 0.7, the viscosity may become too high.

As for the molecular weight of the component (A), the weight average molecular weight (Mw) in terms of standard polystyrene as measured by gel permeation chromatography (GPC) using a THF solvent is preferably 500 to 100,000, preferably 700 to 50,000. More preferably, 1,000 to 30,000 is even more preferable.

Specific examples of the component (A) include those represented by the following average formulas (3) to (5), but are not limited thereto.
The organopolysiloxane of the component (A) may be used alone or in combination of two or more.

[In the formula, Me represents a methyl group, Ph represents a phenyl group, and Vi represents a vinyl group (the same applies hereinafter). In the formula (3), the sequence order of the siloxane units is arbitrary. ]

[2] Component (B) The component (B) in the photocurable silicone composition used in the present invention has at least two Si—H bonds in one molecule represented by the following average composition formula (2). Organohydrogen polysiloxane.
^{_{_{_{R 3 d H e SiO [(}}}} 4-de) / 2] (2)

In formula (2), R ³ independently represents a substituted or unsubstituted monovalent hydrocarbon group excluding the aliphatic unsaturated hydrocarbon group.
The monovalent hydrocarbon group of R ³ is not particularly limited as long as it does not have an aliphatic unsaturated hydrocarbon group, and may be linear, branched, or cyclic, but those having 1 to 20 carbon atoms are used. Preferably, one having 1 to 10 carbon atoms is more preferable, and one having 1 to 5 carbon atoms is even more preferable.
Specific examples thereof include linear or branched alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl and n-hexyl groups; cyclic alkyl groups such as cyclohexyl groups; phenyl and trill groups. And other aryl groups; examples thereof include aralkyl groups such as benzyl and phenylethyl groups.
Further, a part or all of the hydrogen atoms of these monovalent hydrocarbon groups may be substituted with halogen atoms such as F, Cl and Br, cyano groups and the like, and specific examples of such groups include. Halogen-substituted hydrocarbon groups such as 3,3,3-trifluoropropyl group; cyano-substituted hydrocarbon groups such as 2-cyanoethyl group and the like can be mentioned.
Among these, a methyl group is preferable.

Further, from the viewpoint of compatibility with the component (A) and physical properties of the cured product, 20 mol% or more of the total number of R ³ and Si—H groups in the component (B) is preferably a methyl group, and 50 A methyl group is more preferable in terms of molar% or more.

In the formula (2), d is a number of 0.7 ≦ d ≦ 2.5, preferably a number of 0.7 ≦ d ≦ 2.1, and a number of 1.0 ≦ d ≦ 1.8. More preferred. If d is less than 0.7, foaming may occur during curing, and the change in hardness with time tends to be large. If d exceeds 2.5, sufficient hardness cannot be obtained.
Although e is a number of 0.01 ≦ e ≦ 1.0, a number of 0.02 ≦ e ≦ 1.0 is preferable, and a number of 0.1 ≦ e ≦ 1.0 is more preferable. If e is less than 0.01, sufficient hardness cannot be obtained, and if it exceeds 1.0, foaming may occur during curing, and the hardness change with time tends to be large.
d + e satisfies 0.8 ≦ d + e ≦ 2.7, preferably 1 ≦ d + e ≦ 2.4, and more preferably 1.6 ≦ d + e ≦ 2.2. If d + e is less than 0.8, the cured product tends to be hard and brittle, so that cracks are likely to occur in the adhesive layer, and if it exceeds 2.7, the cured product becomes soft and the reinforcing property of the laminated body becomes poor.

The kinematic viscosity of the component (B) component organohydrogenpolysiloxane at 25 ° C. is preferably 1,000 mm ² / s or less, more preferably 0.5 to 1,000 mPa · s, and more preferably 1 to 500 mm ² / s. More preferred. In the present invention, the kinematic viscosity is a measured value using a Canon Fenceke viscometer.

The blending amount of the organohydrogenpolysiloxane of the component (B) is 1 to 200 parts by mass with respect to 100 parts by mass of the component (A), but 5 to 80 parts by mass is preferable. If the blending amount is less than 1 part by mass, the curability becomes insufficient, and if it exceeds 200 parts by mass, sufficient hardness and strength cannot be obtained.
Further, in the organohydrogenpolysiloxane of the component (B), the molar ratio of the silicon atom-bonded hydrogen atom (that is, SiH group) in the component (B) to the alkenyl group in the component (A) is 0.5 to 2. It is preferably blended in an amount of mol / mol, and more preferably blended in an amount of 1 to 1.5 mol / mol.

Specific examples of the component (B) include those represented by the following average formulas (6) to (8), but are not limited thereto.
The organohydrogenpolysiloxane of the component (B) may be used alone or in combination of two or more.
Me _2.0 H _0.1 SiO _{[1.9 / 2]} (6)
Me _1.8 H _0.3 SiO _{[1.9 / 2]} (7)
Me _1.7 H _0.4 SiO _{[1.9 / 2]} (8)

[3] Component (C) The component (C) in the photocurable silicone composition used in the present invention coordinates at least one of a β-diketonato group, a β-ketoesterate group, and a 1,3-diesterate group. It is a platinum compound having as a child. Although this platinum compound is inactive in the shaded state, it changes to a platinum catalyst that is active at room temperature when irradiated with light having a wavelength of 380 to 420 nm, and the alkenyl group in the above-mentioned component (A) and ( B) It has a function of promoting the hydrosilylation reaction with the silicon atom-bonded hydrogen atom in the component.

Specific examples of the component (C) include a trimethyl (acetylacetonato) platinum complex, a trimethyl (2,4-pentanetone) platinum complex, a trimethyl (3,5-heptanzionate) platinum complex, and a trimethyl (methylacetoacetate). ) Platinum complex, bis (acetylacetonato) platinum complex, bis (2,4-pentandionato) platinum complex, bis (2,4-hexandionato) platinum complex, bis (2,4-heptandionat) platinum complex, Examples thereof include a bis (3,5-heptandionat) platinum complex, a bis (1-phenyl-1,3-butandionato) platinum complex, and a bis (1,3-diphenyl-1,3-propanedionat) platinum complex. May be used alone or in combination of two or more.
Among these, a bis (acetylacetonato) platinum complex and a derivative modified on the acetylacetonato group thereof are preferable.

The content of the component (C) is not limited as long as it is an amount that promotes curing (hydrosilylation reaction) of the photocurable silicone composition, but the metal atoms in the composition are mass-converted with respect to the component (A). The amount in the range of 0.01 to 500 ppm is preferable, the amount in the range of 0.05 to 100 ppm is more preferable, and the amount in the range of 0.01 to 50 ppm is even more preferable.

[4] Component (D) The photocurable silicone composition used in the present invention has adhesiveness to a substrate such as a polarizing plate, glass, polycarbonate resin or acrylic resin as a component (D), if necessary. Adhesive aids for imparting may be added.
Among the components (D), specific examples of the adhesion aid containing a siloxane bond include vinyl trimethoxysilane (KBM-1003 manufactured by Shin-Etsu Chemical Industry Co., Ltd.) and γ- (glycidyloxypropyl) trimethoxysilane ( Shin-Etsu Chemical Industry Co., Ltd., KBM-403), γ- (methacryloxypropyl) trimethoxysilane (Shin-Etsu Chemical Industry Co., Ltd., KBM-503), their hydrolyzates, and the following structural formulas. Examples thereof include compounds to be used.

Specific examples of the adhesive aid containing no siloxane bond include allyl glycidyl ether, vinyl cyclohexene monooxide, diethyl 2-allyl malonate, diallyl bisphenol ether, allyl benzoate, diallyl phthalate, and tetraallyl ester pyromellitic acid. TRIAM805) manufactured by Fujifilm Wako Junyaku Co., Ltd., triallyl isocyanurate, and the like.
The component (D) may be used alone or in combination of two or more.

When the component (D) is used, the amount added is preferably 0.05 to 10 parts by mass, more preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the component (A). When the blending amount of the component (D) is within the above range, appropriate adhesiveness can be imparted.

[5] Ingredients (E) The photocurable silicone adhesive composition used in the present invention includes thickening and gel before heat curing such as when preparing the composition or when applying the composition to a substrate. If necessary, the reaction control agent (E) may be added for the purpose of controlling the reactivity of the hydrosilylation reaction catalyst so as not to cause the formation.
Specific examples of the reaction control agent include 3-methyl-1-butyne-3-ol, 3-methyl-1-pentyne-3-ol, 3,5-dimethyl-1-hexin-3-ol, and 1-ethynyl. Cyclohexanol, ethynylmethyldecylcarbinol, 3-methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 1-ethynyl-1-trimethylsiloxycyclohexane, bis (2,2-dimethyl-3-butynoxy) dimethylsilane, 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane, Examples thereof include 1,1,3,3-tetramethyl-1,3-divinyldisiloxane, which may be used alone or in combination of two or more.
Among these, 1-ethynylcyclohexanol, ethynylmethyldecylcarbinol, 3-methyl-1-butyne-3-ol, and bis (2,2-dimethyl-3-butynoxy) dimethylsilane are preferable.

The blending amount of the component (E) is preferably 0.01 to 2.0 parts by mass, more preferably 0.01 to 0.1 parts by mass with respect to 100 parts by mass of the total of the component (A). Within such a range, the effect of reaction control is fully exhibited.

[6] Other Ingredients In addition to the above components (A) to (E), the photocurable silicone adhesive composition used in the present invention contains other components exemplified below as long as the object of the present invention is not impaired. It may be contained.
Other components include, for example, a thixophilic control agent such as fumed silica; a reinforcing agent such as crystalline silica; an antioxidant; a light stabilizer; a heat resistance improver such as a metal oxide and a metal hydroxide; and titanium oxide. Colorants such as: Thermal conductivity-imparting fillers such as alumina and crystalline silica; Viscosity modifiers such as non-reactive silicone oil having no reactive functional group; Conductivity-imparting agents such as metal powders such as silver and gold And so on.

The photocurable silicone adhesive composition used in the present invention is a mixture of the above components (A) to (C), components (D) and (E) used as necessary, and other components by a known method. Can be prepared.

[Manufacturing method of laminate]
A method for producing a laminate using the above-mentioned photocurable silicone adhesive composition will be described.
The above-mentioned photocurable silicone adhesive composition is suitably used as a composition for forming an adhesive layer when two base materials constituting a laminate such as an optical device, a display, and a touch panel are bonded together via an adhesive layer. it can.
In this case, the method for producing the laminate includes a coating step, a light irradiation step, a curing step, and a bonding step, and details of each step include, for example, those shown below.

(I) Coating Step In the coating step, the above-mentioned photocurable silicone adhesive composition is coated on a base material (first base material).
Examples of the coating method include coating using a slit coat, a DAM-Fill method, a fishbone method, and the like.
The coating amount is not particularly limited, but is preferably an amount such that the thickness of the silicone layer after curing is 100 to 5,000 μm.

Examples of the base material include polarizing materials and composite materials, metal members, plastic members, ceramic members, etc., and in particular, casings for electrical applications, electronic applications, optical applications, etc., coating of members, casting, bonding, sealing, etc. It is useful for those used in the above fields, and is particularly useful for polarizing plates and polarizing films.
The photocurable silicone adhesive composition can also be used for a substrate activated by a well-known pretreatment step such as primer treatment, plasma treatment, and excimer light treatment.

(Ii) Light Irradiation Step In the light irradiation step, the photocurable silicone adhesive composition is irradiated with light.
Examples of the light irradiation method include a method of using a lamp having a peak wavelength of 380 to 420 nm as a light source and irradiating an appropriate amount of light.
As the light source, a 405 nm UV-LED lamp is preferable.
The light to be irradiated is light having a peak wavelength of 380 to 420 nm, preferably 395 to 410 nm, and more preferably 405 nm.
The temperature at the time of light irradiation is preferably 5 to 60 ° C., more preferably 5 to 35 ° C. from the viewpoint of curing speed and prevention of discoloration.
The irradiation intensity is preferably 300 to 2,000 mW / cm ² , and the irradiation dose is preferably 1,000 to 20,000 mJ / cm ² from the viewpoint of curability and workability.

(Iii) Curing Step In the curing step, the light-irradiated composition is cured.
The curing method is not particularly limited, and examples thereof include a method in which a light-irradiated composition is allowed to stand in a predetermined environment to be cured to form an adhesive layer.
The curing temperature is not particularly limited, but is preferably 5 to 60 ° C., more preferably 5 to 35 ° C., from the viewpoint of suppressing warpage and deterioration due to thermal expansion / contraction of the laminate.
The curing atmosphere is arbitrary, but is preferably in an air atmosphere.
The curing time is not particularly limited, but is preferably about 1 minute to 24 hours.

(Iv) Laminating Step In the laminating step, the second base material is laminated on the photocurable silicone adhesive composition or the adhesive layer, and the two base materials are combined with the adhesive composition or the adhesive layer. A laminated body is formed which is bonded to each other.
As a bonding method, an adhesive layer-base material laminate that has changed from a liquid to a semi-solid state through a coating step, a light irradiation step, and a curing step, a photocurable silicone adhesive composition after the coating step, or a bonding method. The photocurable silicone adhesive composition layer-base material laminate after the coating step and the light irradiation step is installed in a vacuum or atmospheric pressure bonding device, and the second base material is a photocurable silicone adhesive composition or Examples thereof include a method of laminating and laminating on an adhesive layer, and in the case of a composition, performing the remaining steps to cure and form a laminated body.

The method for producing a laminate of the present invention is a flat display or a curved display because it is not hindered by oxygen and the curing time after irradiation with light can be changed depending on the design of the adhesive composition and the heating temperature. Etc., the procedures of the coating process, the light irradiation process, the curing process, and the bonding process can be freely selected and changed according to the structure of the device to be manufactured.

Specific examples of the method for manufacturing the laminate of the present invention include a method for producing a laminate having a cover panel and an image display panel.
First, the photocurable silicone composition of the present invention is applied onto a polarizing plate constituting an image display panel. After that, using a UV-LED lamp having a wavelength peak of 405 nm, light with an irradiation intensity of 100 mW / cm ² using 405 nm light as an index was applied to the photocurable silicone composition at 25 ° C. for 100 seconds at a dose of 10, Irradiate to 000 mJ / cm ² . Subsequently, the silicone composition is allowed to stand in an environment of 25 ° C. for 30 minutes to cure the silicone composition to form an adhesive layer. Then, the cover panel is laminated on the adhesive layer using a vacuum bonding device to obtain a laminated body in which the cover panel and the image display panel are bonded via the adhesive layer.
Further, after the light irradiation step, the cover panel is first laminated on the silicone composition using a vacuum bonding device, so that the image display panel and the cover panel are bonded via the silicone composition, and then at 25 ° C. The silicone composition may be cured by allowing it to stand in the environment for 30 minutes. Alternatively, since the cover panel is transparent, vacuum bonding may be performed after the coating step, and then light irradiation may be performed through the cover panel to cure the cover panel. Further, the silicone composition that has been irradiated with light in advance may be applied to the image display panel, vacuum-bonded to the cover panel, and cured.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.
In the following example, Mw represents the weight average molecular weight in terms of standard polystyrene measured by GPC using a THF solvent.

[Production Examples 1 and 2 and Comparative Production Examples 1 and 2]
The following components were mixed in the blending amounts (parts by mass) shown in Table 1 to prepare a photocurable silicone composition.
(A) Ingredient:
(A-1) Organopolysiloxane (Mw: 28,000) represented by the following average structural formula (3).

(In the formula, the sequence order of siloxane units is indefinite.)

(A-2) Organopolysiloxane (Mw: 22,400) represented by the following average structural formula (4).

(A-3) Organopolysiloxane (Mw: 16,500) represented by the following average formula (5)
(ViMe ₂ Si) _0.57 (Me ₃ SiO) _1.43 (Me ₂ SiO) ₂₂₀ (5)

(B) Ingredient:
(B-1) Dimethylsiloxane Me _2.0 H _0.1 SiO _{[1.9 / 2]} , which is represented by the following average composition formula (6) and has a kinematic viscosity of 17 mm ² / s at 23 ° C. and a hydrodimethylsiloxy group blockade at both ends of the molecular chain _. (6)
(B-2) Dimethylsiloxane Me _1.8 H _0.3 SiO _{[1.9 / 2]} , which is represented by the following average composition formula (7) and has a kinematic viscosity of 27 mm ² / s at 23 ° C. and a hydrodimethylsiloxy group blockade at both ends of the molecular chain _. (7)
(B-3) Dimethylsiloxane Me _1.7 H _0.4 SiO _{[1.9 / 2]} , which is represented by the following average composition formula (8) and has a kinematic viscosity at 23 ° C. of 105 mm ² / s and a hydrodimethylsiloxy group blockade at both ends of the molecular chain _. (8)

(C) component:
(C-1) Ethyl acetate 2- (2-butoxyethoxy) ethyl acetate solution of bisacetylacetonato platinum complex (platinum content 0.5% by mass)
(C-2) Comparative component Toluene solution of trimethyl (methylcyclopentadienyl) platinum complex (platinum content 0.5% by mass)

Component (D): Adhesive aid (D-1) 7-octenyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-1083)
(D-2) Compound represented by the following structural formula (10)

(D-3) Compound represented by the following structural formula (11)

Component (E): Reaction control agent (E-1) Compound represented by the following formula (9)

Other ingredients:
Fumed silica (Aerosil NSX-200 (average primary particle size 8 nm), Nippon Aerosil Co., Ltd.)

[Examples 1 and 2 and Comparative Examples 1 to 4]
The gelation time of the photocurable silicone adhesive composition prepared in each of the above production examples and the comparative production examples was evaluated by the following method. The results are shown in Table 2.
[Gelification time]
The gelation time was measured using a viscoelasticity measuring device ARES-G2 (manufactured by TA Instruments Japan Co., Ltd.) equipped with a UV curing accessory.
1 ml of each of the prepared photocurable silicone compositions was applied to a stainless steel plate portion or each of the following polarizing plates fixed on the plate portion, and a UV-LED lamp having a peak wavelength of 365 nm (Panasonic Corporation). ANOJ6186 (manufactured by ANOJ6186) or a UV-LED lamp having a wavelength of 405 nm (ANOJ6189, manufactured by Panasonic Corporation) was used to irradiate each composition with 100 mW / cm ² light at 25 ° C. to 10,000 mJ / cm ² . ..
Then, the temperature was maintained at 25 ° C., and the viscoelasticity was measured. The time (minutes) required from the completion of UV irradiation until tan δ = 1 was defined as the gelation time.

Polarizing plate 1: NPF-CWQ1463VCU manufactured by Nitto Denko Corporation
Polarizing plate 2: NAZ-EFCFWQVAG15AR manufactured by Nitto Denko Corporation
Polarizing plate 3: NAZ-EFCFWQVAG150 manufactured by Nitto Denko Corporation
Polarizing plate 4: NPF-CWQ1463VCUAG15ARS manufactured by Nitto Denko KK
Polarizing plate 5: NPF-SWQ1423CUARC380 manufactured by Nitto Denko Corporation
Polarizing plate 6: NPF-CWQ1463VCUAG150 manufactured by Nitto Denko Corporation

As shown in Table 2, according to the method for producing a laminate of the present invention, the photocurable silicone composition is rapidly cured at 25 ° C. regardless of the type of polarizing plate to be contacted, and the touch panel, display, etc. It can be said that it has been shown that it can be suitably used for bonding image display devices.
On the other hand, in Comparative Examples 1 and 2 using an addition reaction catalyst other than the component (C) of the present invention, curing by light irradiation using an LED light source having a peak wavelength of 405 nm did not occur, and the light source in Examples 1 and 2 peaked. It can be seen that in Comparative Examples 3 and 4 in which the LED light source having a wavelength of 365 nm was changed, curing inhibition due to the polarizing plate may occur.

Claims

A method for producing a laminate including a first base material and an adhesive layer laminated on the first base material.
A laminate characterized by forming the adhesive layer by irradiating a photocurable silicone composition containing the following components (A) to (C) with light having a peak wavelength of 380 to 420 nm and curing the adhesive layer. Production method.
(A) Linear organopolysiloxane represented by the following average formula (1): 100 parts by mass (R 1 R 2 2 SiO 1/2 ) a (R 2 3 SiO 1/2 ) 2-a (Ar 2) SiO 2/2 ) b (R 2 2 SiO 2/2 ) c (1)
{In the formula, R 1 independently represents a substituted or unsubstituted alkenyl group, R 2 independently represents a substituted or unsubstituted alkyl group, and Ar independently represents a substituted or unsubstituted alkyl group. It represents a substituted or unsubstituted aryl group, a represents a number of 0.3 to 2, b is 0 to 100, c is 1 to 1,000, and b / (b + c) = 0 to 0. . Represents a number that satisfies 7. }
(B) represented by the following average compositional formula (2), organohydrogenpolysiloxane having at least two Si-H bonds in one molecule: 1 to 200 parts by weight R 3 d H e SiO [( 4- de) / 2] (2)
(In the formula, R 3 independently represents a substituted or unsubstituted monovalent hydrocarbon group excluding the aliphatic unsaturated hydrocarbon group, and d and e are 0.7 ≦ d ≦ 2.5, respectively. It represents a number that satisfies 0.01 ≦ e ≦ 1.0 and 0.8 ≦ d + e ≦ 2.7.)
(C) A platinum compound having at least one of a β-diketonato group, a β-ketoesterate group, and a 1,3-diesterate group as a ligand.
The method for producing a laminate according to claim 1, wherein the component (C) is bisacetylacetonato platinum (II).
(I) A coating step of applying the photocurable silicone composition to the surface of the first substrate, and
(Ii) A light irradiation step of irradiating a photocurable silicone composition with light having a peak wavelength of 380 to 420 nm, and
(Iii) A curing step of curing a photocurable silicone composition to form an adhesive layer,
(Iv) Laminating a second base material on a photocurable silicone composition or an adhesive layer, and laminating the first and second base materials via the adhesive composition or the adhesive layer. The method for producing a laminate according to claim 1 or 2, which includes a step.
The method for producing a laminate according to claim 3, wherein the curing step is performed at 5 to 35 ° C.
The method for producing a laminate according to claim 3 or 4, wherein the second base material is a polarizing plate or a polarizing film.
The method for producing a laminate according to any one of claims 1 to 5, wherein the first base material is a polarizing plate or a polarizing film.
The method for producing a laminate according to any one of claims 1 to 6, wherein the peak wavelength of the light is 405 nm.
The method for manufacturing a laminate according to any one of claims 1 to 7, wherein the laminate is an image display device.