TW202100349A - Display body and adhesive sheet in which the display body at least includes a display body constituting element, an other display body constituting element, and an adhesive layer for bonding the display body constituting element and the other display body constituting elements - Google Patents

Abstract

The object of the present invention is to provide a display body with improved design and an adhesive sheet that can improve the design of the display body. A display body 2 has a display unit and a non-display unit. The display body 2 at least includes a display body constituting element 21, an other display body constituting element 22, and an adhesive layer 11 for bonding the display body constituting element 21 and the other display body constituting elements 22. The total light transmittance of the adhesive layer 11 in the display unit is 3% or more. According to the color system defined by CIE1976 L*a*b*, when the lightness L* of the display unit being L*2, the chromaticity a* of the display unit is a*2, the chromaticity b* of the display unit is b*2, the lightness L* of the non-display unit is L*3, the chromaticity a* of the non-display unit is a*3, and the chromaticity b* of the non-display unit is b*3, the color difference [Delta]E calculated by the following formula (I) is 2.00 or less.

Description

Display body and adhesive sheet

The present invention relates to a suitable display body for vehicles, etc., and an adhesive sheet used for the display body.

Displays (displays) in recent years, such as automotive display panels, car navigation systems, various meters installed on the dashboard, display bodies such as tablet terminals for general users, and commercial tablet terminals Or display bodies such as digital signage, and display bodies such as outdoor digital signage, and more use image display devices such as liquid crystal display devices or organic light emitting diode devices.

In the above-mentioned display bodies for vehicles, it is required that when the lamp of the display body is turned off, the display part of the display body and the non-display part, such as peripheral elements such as frame materials, should be coordinated in appearance and improved design. . Therefore, considering the coloring of the display, for example, patent documents 1 to 4 disclose inventions related to the coloring of the display. [Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2000-313871 [Patent Document 2] JP 2009-188298 A [Patent Document 3] JP 2012-234028 A [Patent Document 4] JP 2017-57375 A

[Problems to be solved by the invention]

However, the technologies disclosed in Patent Documents 1 to 4 listed above have different purposes of coloring. Therefore, it is impossible to coordinate the appearance of the display portion and the non-display portion and improve the design when the display body is turned off.

The present invention is made in view of the above-mentioned actual situation, and aims to provide a display with improved design and an adhesive sheet that can improve the design of the display. [Means to solve the problem]

。In order to achieve the above-mentioned object, first, the present invention provides a display body having a display portion and a non-display portion, and at least one display body constituent element and other display body constituent elements, and the aforementioned one display body constituent element and The above-mentioned other display body constitutes a display body of an adhesive layer to which an element is bonded, characterized in that the total light transmittance of the adhesive layer in the display portion is 3% or more, according to CIE1976 L*a*b* The system stipulates that the lightness L* of the display part is L*2, the chromaticity a* of the display part is a*2, the chromaticity b* of the display part is b*2, and the lightness L of the non-display part * Is L*3, the chromaticity a* of the non-display portion is a*3, and the chromaticity b* of the non-display portion is b*3, the color difference ΔE calculated by the following formula (I) is 2.00 or less (Invention 1 )

.

In the above invention (Invention 1), since the total light transmittance is 3% or more, the visibility of the screen and image when the display body is lit can be ensured. In addition, since the color difference ΔE is as described above, it is possible to achieve the coordination of the appearance of the display portion and the non-display portion when the indicator light is off, and it becomes a design enhancer.

In the above invention (Invention 1), it is preferable that L*3 of the non-display part is 0.1 to 50, a*3 of the non-display part is -20 to 20, and b*3 of the non-display part is -20 ~20 (Invention 2).

In the above inventions (Inventions 1 and 2), it is preferable that the non-display portion is black (Invention 3).

In the above inventions (Inventions 1 to 3), it is preferable that at least one of the one display component and the other display component has a convex portion on the surface on the side of the adhesive layer, and the convex portion constitutes the non- Part or all of the display unit (Invention 4).

。Secondly, the present invention provides an adhesive sheet having an adhesive layer for bonding one of the display constituent elements and other display constituent elements that constitute a display having a display portion and a non-display portion, It is characterized in that the total light transmittance of the adhesive layer is 3% or more, and the adhesive layer is colored so that the one display component and the other display component are bonded via the adhesive layer. The obtained display body meets the requirements of the CIE1976 L*a*b* color system, and the lightness L* of the display part is L*2, the chromaticity a* of the display part is a*2, and the display The chromaticity b* of the part is b*2, the lightness L* of the non-display part is L*3, the chromaticity a* of the non-display part is a*3, and the chromaticity b* of the non-display part is b* At 3, the color difference ΔE calculated by the following formula (I) is 2.00 or less (Invention 5)

.

In the above invention (Invention 5), it is preferable that the lightness L* of the adhesive layer is L*1 in accordance with the CIE1976 L*a*b* color system, and the chromaticity a* of the adhesive layer When the chromaticity b* of the adhesive layer is b*1, the L*1 of the adhesive layer is 5 to 95, and the a*1 of the adhesive layer is -20 to 20, and the adhesive The b*1 of the layer is -20 to 20 (Invention 6).

In the above inventions (Inventions 5 and 6), it is preferable that the haze value of the adhesive layer is 0.1% or more and 80% or less (Invention 7).

In the above inventions (Inventions 5 to 7), it is preferable that the adhesive constituting the adhesive layer contains a coloring agent (Invention 8).

In the aforementioned invention (Invention 8), it is preferable that the aforementioned colorant is a black pigment or dye (Invention 9).

In the above inventions (Inventions 5 to 9), it is preferable to have two release sheets and the adhesive layer in contact with the release surfaces of the two release sheets and sandwiched between the release sheets (Invention 10). [Invention Effect]

The display body of the present invention becomes a coordinated appearance and improved design of the display part and the non-display part when the light is off. Furthermore, according to the adhesive sheet of the present invention, the design of the display body can be improved.

Hereinafter, embodiments of the present invention will be described. [Display body] A display body (display) according to one embodiment of the present invention has a display portion and a non-display portion, and has at least one display body constituent element and other display body constituent elements, and a display body constituent element and other display body constituent elements Laminated adhesive layer.

The types of displays in this embodiment include, for example, car mounting panels, car navigation systems, car displays such as various meters installed on the dashboard, displays such as tablet terminals for general users, and flat panels for commercial use. Displays such as terminals and digital signs, and displays such as outdoor digital signs. However, the display body of the present invention is not limited to these.

In addition, the types of display devices of the display of this embodiment, such as liquid crystal (LCD) displays, light emitting diodes (LED) displays, organic light emitting diodes (organic EL) displays, e-books, etc., may also be touch-sensitive panel.

The display portion of the display in this embodiment refers to a portion that displays screens and images via the above-mentioned display device. In addition, the non-display portion of the display in this embodiment refers to a portion of the display that does not display screens or images. For example, it corresponds to a portion where a frame-like printed layer is formed on the display component or is provided in the display structure. Elements such as the periphery of the element, and element parts such as the element of the split screen.

In the display of this embodiment, the total light transmittance of the adhesive layer in the display portion is 3% or more. With a total light transmittance of 3% or more, the visibility of the screen and image when the display body is on can be ensured. In addition, the total light transmittance in this specification is a value measured in accordance with JIS K7361-1:1997.

In addition, in the display of this embodiment, according to the CIE1976 L*a*b* color system, the lightness L* of the display part is L*2, and the chromaticity a* of the display part is a*2. When the chromaticity b* is b*2, the lightness L* of the non-display part is L*3, the chromaticity a* of the non-display part is a*3, and the chromaticity b* of the non-display part is b*3, the following The color difference ΔE calculated by the formula (I) is 2.00 or less.

In the display body of the present embodiment, since the color difference ΔE is as described above, it is possible to achieve the coordination of the appearance of the display portion and the non-display portion when the display body is turned off, and it becomes a design enhancer. In addition, the measurement methods of lightness L*, chromaticity a*, and chromaticity b* in this specification are as shown in the test examples described later.

From the viewpoint of visibility of screens and images, the total light transmittance of the adhesive layer in the display portion is 3% or more, preferably 10% or more, more preferably 25% or more, particularly preferably 40% or more, and still more Preferably, it is 50% or more. The upper limit of total light transmittance is usually 100% or less. When considering the relationship with the above-mentioned color difference ΔE, it is preferably 98% or less, more preferably 90% or less, particularly preferably 80% or less, and even more preferably 70 % Or less, preferably 57% or less.

In addition, from the viewpoint of the appearance coordination of the display part and the non-display part, the color difference ΔE is 2.00 or less, preferably 1.80 or less, more preferably 1.50 or less, and particularly preferably 1.20 or less. When considering the visibility of screens and images , It is more preferably below 1.00, and the best below 0.80. The lower limit of the color difference ΔE is not particularly limited, and the minimum value is 0. However, when considering the relationship with the above-mentioned total light transmittance, it is preferably 0.01 or more, particularly 0.05 or more, and more preferably 0.1 or more.

It is preferable that the L*3 of the non-display part is 0.1-50, the a*3 of the non-display part is -20-20, and the b*3 of the non-display part is -20-20, and the L*3 of the non-display part 0.5 to 30, a*3 of the non-display part is -10 to 10, and b*3 of the non-display part is -10 to 10 is more preferable, especially when L*3 of the non-display part is 1.0 to 10, the non-display part The a*3 of the non-display part is -5 to 5, the b*3 of the non-display part is preferably -5 to 5, and the L*3 of the non-display part is 2.0 to 5.0, and the a*3 of the non-display part is- 1 to 1, the b*3 of the non-display part is preferably -1 to 1. Through these, it is easy to satisfy the above-mentioned color difference ΔE, and the non-display portion in the display body has a preferable color tone. The non-display part is preferably black.

On the other hand, the L*2 of the display section is 0.1-50, the a*2 of the display section is -20-20, and the b*2 of the display section is -20-20. The L*2 of the display section 0.5-30, a*2 of the display part is -10-10, and b*2 of the display part is -10-10, especially L*2 of the display part is 1.0-10, a* of the display part 2 is from -5 to 5, the b*2 of the display part is preferably from -5 to 5, and the L*2 of the display part is 2.0 to 5.0, and the a*2 of the display part is -1 to 1. b*2 is -1 to 1 is better. Through these, it is easy to satisfy the above-mentioned color difference ΔE, and the display portion in the display body has a better hue when the display body is turned off. The display part is preferably black.

In addition, according to the CIE1976 L*a*b* color system, the lightness L* of the adhesive layer used in this embodiment is L*1, and the chromaticity a* of the adhesive layer is a*1. When the chromaticity b* of the layer is b*1, the L*1 of the adhesive layer is 5 to 95, the a*1 of the adhesive layer is -20 to 20, and the b*1 of the adhesive layer is -20 to 20 The L*1 of the adhesive layer is 8～93, the a*1 of the adhesive layer is -10～10, and the b*1 of the adhesive layer is -10～10. L*1 of the adhesive layer is preferably 10 to 90, a*1 of the adhesive layer is -5 to 5, and b*1 of the adhesive layer is preferably -5 to 5. Through these, it is easy to satisfy the above-mentioned chromatic aberration ΔE and total light transmittance. The above-mentioned adhesive layer is preferably colored to be black.

In the above formula (I), the difference (L*2-L*3) between the lightness L*2 of the display part and the lightness L*3 of the non-display part is preferably -2.00～2.00, but when considering the chromaticity of the display part The difference between a*2 and the chromaticity a*3 of the non-display part (a*2-a*3) and the difference between the chromaticity b*2 of the display part and the chromaticity b*3 of the non-display part (b*2－ In the relationship of b*3), -1.50 to 1.50 is preferred, -1.00 to 1.00 is preferred, especially -0.80 to 0.80 is preferred, -0.60 to 0.60 is more preferred, and -0.40 to 0.40 is most preferred. Through these, the above-mentioned color difference ΔE is easily satisfied.

In the above formula (I), the difference (a*2-a*3) between the chromaticity a*2 of the display part and the chromaticity a*3 of the non-display part is preferably -2.00～2.00, but when considering the display part The difference between the lightness L*2 and the lightness L*3 of the non-display part (L*2－L*3) and the difference between the chromaticity b*2 of the display part and the chromaticity b*3 of the non-display part (b*2－ In the relationship of b*3), -1.50 to 1.50 is preferable, 1.00 to 1.00 is more preferable, －0.80 to 0.80 is especially preferable, －0.60 to 0.60 is more preferable, and －0.54 to 0.54 is more preferable. Through these, the above-mentioned color difference ΔE is easily satisfied.

In the above formula (I), the difference between the chromaticity b*2 of the display part and the chromaticity b*3 of the non-display part (b*2－b*3) is preferably -2.00～2.00, but when considering the display part The difference between the lightness L*2 and the lightness L*3 of the non-display part (L*2－L*3) and the difference between the chromaticity a*2 of the display part and the chromaticity a*3 of the non-display part (a*2－ In the relationship of a*3), -1.50 to 1.50 is preferred, -1.00 to 1.00 is preferred, especially -0.80 to 0.80 is preferred, -0.50 to 0.50 is more preferred, and -0.25 to 0.25 is most preferred. Through these, the above-mentioned color difference ΔE is easily satisfied.

Here, it is preferable that at least one of the above-mentioned one display body constituent element and the other display body constituent elements has a convex portion on the surface on the side where the adhesive layer is bonded. In this case, the convex portion may constitute a part or all of the aforementioned non-display portion. For such a convex portion, for example, a printed layer or the like in a frame shape in plan view is formed on the adhesive layer side of the display component. An example of a display body having such a convex portion will be described below with reference to the drawings.

As shown in FIG. 1, the display body 2 of this embodiment has a first display body constituent element 21 (a display body constituent element), a second display body constituent element 22 (other display body constituent elements), and a In between, the first display component 21 and the second display component 22 are formed by an adhesive layer 11 that is bonded to each other. In this embodiment, the first display component 21 has the printed layer 3 as an example of the convex portion on the surface on the adhesive layer 11 side. For this reason, the printed layer 3 of the convex portion forms a step with respect to the portion where the printed layer 3 does not exist.

In addition to glass plates, plastic plates, etc., the first display body component 21 is preferably a protective panel composed of laminates containing these, especially plastic plates, or laminates containing plastic plates, etc. The protective panel is better. In this case, the printed layer 3 is generally formed in a frame shape on the adhesive layer 11 side of the first display component 21.

The above-mentioned glass plate is not particularly limited, such as chemically strengthened glass, alkali-free glass, quartz glass, soda lime glass, barium and strontium-containing glass, aluminosilicate glass, lead glass, borosilicate glass, barium borosilicate glass Wait. The thickness of the glass plate is not particularly limited, but is usually 0.1 to 5 mm, preferably 0.2 to 2 mm.

The above-mentioned plastic plates are not particularly limited, and for example, acrylic resin plates such as polycarbonate resin (PC) plates, polymethyl methacrylate resin (PMMA) plates, etc., polycarbonate resin plates are laminated with methyl methacrylate resin layers, etc. The acrylic resin layer of plastic board, etc. In addition, the above-mentioned polycarbonate resin sheet may contain resins other than polycarbonate resin as a material constituting it, and the above-mentioned acrylic resin sheet may also contain resins other than acrylic resin as a material constituting it. In addition, this plastic plate may be one with an ultraviolet absorber added.

The thickness of the plastic plate is not particularly limited, and is usually 0.2-5 mm, preferably 0.4-3 mm, particularly preferably 0.6-2.5 mm.

Various functional layers (transparent conductive film, metal layer, silicon oxide layer, hard coating layer, anti-glare film layer, etc.) can be provided on one or both sides of the glass plate or plastic plate, and optical elements can also be laminated. In addition, the transparent conductive film and the metal layer may also be patterned.

The second display body constituent element 22 is an optical element that should be attached to the first display body constituent element 21, a display body module (for example, a liquid crystal (LCD) module, a light emitting diode (LED) module, an organic light emitting diode) (Organic EL) modules, etc.), optical elements as part of the display module, or a laminate including the display module.

The above-mentioned optical elements such as anti-scattering film, polarizing plate (polarizing film), polarizer, retardation plate (phase difference film), viewing angle compensation film, brightness enhancement film, contrast enhancement film, liquid crystal polymer film, diffusion film, semi-transmissive reflection Film, transparent conductive film, etc. The anti-scattering film is, for example, a hard coat film formed by forming a hard coat layer on one surface of a base film.

The material constituting the printing layer 3 is not particularly limited, and known materials for printing can be used. The lower limit of the thickness of the printed layer 3, that is, the height of the step difference, is preferably 3 μm or more, preferably 5 μm or more, particularly preferably 7 μm or more, and more preferably 10 μm or more. The lower limit of the height of the transmission step is the above-mentioned, and it is possible to sufficiently ensure the concealment of the electric wiring etc. from the side of the viewer. In addition, the upper limit of the height of the step is preferably 50 μm or less, more preferably 35 μm or less, particularly preferably 25 μm or less, and more preferably 20 μm or less. The upper limit value of the height of the transmission level difference is as described above, and the deterioration of the level difference followability of the adhesive layer 11 to the printed layer 3 can be prevented.

The adhesive layer 11 can be suitably formed via the adhesive layer of the adhesive sheet demonstrated below. However, as long as the above-mentioned physical properties are satisfied, the present invention is not limited to these.

[Adhesive Sheet] The adhesive sheet of one embodiment of the present invention has an adhesive layer for bonding one of the display body constituent elements and other constituent elements that constitute a display body having a display portion and a non-display portion. It is formed by laminating release sheets on one or both sides of the agent layer.

The adhesive layer in this embodiment is one that has a total light transmittance of 3% or more and is colored with the above-mentioned color difference ΔE satisfying 2.00 or less. These preferred ranges, and the lightness L* (=L*1) of the adhesive layer, the chromaticity a* (=a*1) of the adhesive layer, and the chromaticity b of the adhesive layer in this embodiment The preferable ranges of *(=b*1) are as described above.

The specific structure of an example of the adhesive sheet of this embodiment is shown in FIG. As shown in FIG. 2, the adhesive sheet 1 is composed of two peeling sheets 12a, 12b, and the peeling surfaces of the two peeling sheets 12a, 12b and are sandwiched between the two peeling sheets 12a, 12b. The agent layer 11 is formed. In addition, the peeling surface of the peeling sheet in this specification means the surface which has peelability in a peeling sheet, and includes any one of the surface that has been peeled off and the surface that has not been peeled off but shows peelability.

1. Each component 1-1. Adhesive layer The type of adhesive constituting the adhesive layer 11 of the adhesive sheet 1 of this embodiment is not particularly limited, such as acrylic adhesives, polyester adhesives, polyurethane adhesives, rubber adhesives, silicone adhesives, etc. Either way. In addition, the adhesive may be either an emulsion type, a solvent type, or a solvent-free type, and may be either a crosslinked type or a non-crosslinked type. Among these, acrylic adhesives with excellent adhesive properties and optical properties are preferred.

In addition, the acrylic adhesive may be active energy ray curable or active energy ray non-curable. Furthermore, the acrylic adhesive is preferably a cross-linked type, and more preferably a thermally cross-linked type.

The above-mentioned adhesive is specifically made of an adhesive composition containing (meth)acrylate polymer (A), crosslinking agent (B), and coloring agent (C) (hereinafter referred to as "adhesive composition P" Situation) Cross-linked is better. In addition, when the adhesive is an active energy ray curable adhesive, the adhesive composition P preferably further contains an active energy ray curable component (D).

The adhesive obtained from such an adhesive composition P can exhibit excellent optical properties, adhesive strength, durability (step followability under high temperature and high humidity conditions, blister resistance), etc. In addition, in this specification, (meth)acrylic acid means both acrylic acid and methacrylic acid. Other similar terms are the same. In addition, "polymer" also includes the concept of "copolymer".

(1) Ingredients of adhesive composition (1-1) (Meth)acrylate polymer (A) The (meth)acrylate polymer (A) of this embodiment uses a reactive group-containing monomer having a reactive group that reacts with the crosslinking agent (B) in the molecule as the monomer unit constituting the polymer Better. The reactive group from the monomer containing the reactive group reacts with the cross-linking agent (B) to form a cross-linked structure (three-dimensional network structure) to obtain an adhesive with the desired cohesive force.

The above-mentioned reactive group-containing monomer is preferably, for example, a monomer having a hydroxyl group in the molecule (a hydroxyl group-containing monomer), a monomer having a carboxyl group in the molecule (a carboxyl group-containing monomer), and a monomer having an amine group in the molecule ( Monomers containing amine groups) and so on. Among these, a hydroxyl group-containing monomer or a carboxyl group-containing monomer having excellent reactivity with the crosslinking agent (B) is preferred, and a combination of a hydroxyl group-containing monomer and a carboxyl group-containing monomer may be used.

Hydroxyl-containing monomers, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate , Hydroxyalkyl (meth)acrylates such as 3-hydroxybutyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate. Among them, from the viewpoint of the reactivity of the hydroxyl group in the obtained (meth)acrylate polymer (A) with the crosslinking agent (B) and the copolymerizability with other monomers, a hydroxyalkane having 1 to 4 carbon atoms The hydroxyalkyl (meth)acrylate is preferred. Specifically, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. are preferable examples, and 2-hydroxyethyl acrylate or 4-hydroxybutyl acrylate are particularly preferable examples. These can be used individually or in combination of 2 or more types.

Carboxyl group-containing monomers include, for example, ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Among them, from the viewpoint of the reactivity of the carboxyl group in the obtained (meth)acrylate polymer (A) and the crosslinking agent (B) and the copolymerizability with other monomers, acrylic acid is preferred. These can be used individually or in combination of 2 or more types.

Amino group-containing monomers, for example, aminoethyl (meth)acrylate, n-butylaminoethyl (meth)acrylate, etc. These can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A) contains a reactive group-containing monomer as a monomer unit constituting the polymer, and the lower limit is preferably 1% by mass or more, and particularly containing 5% by mass or more. It is more preferable to contain 10% by mass or more. When the monomer containing a reactive group is a hydroxyl-containing monomer, it is preferably to contain 15% by mass or more, and it is particularly preferable to contain 20% by mass or more. In addition, the (meth)acrylate polymer (A) contains a reactive group-containing monomer as a monomer unit constituting the polymer, and the upper limit is preferably 35% by mass or less, particularly 30% by mass The following is preferable, and it is more preferable to contain 25 mass% or less. When the (meth)acrylate polymer (A) contains a reactive group-containing monomer as a monomer unit in the above-mentioned amount, a good crosslinked structure is formed in the obtained adhesive and the desired aggregation is obtained force. In addition, the dispersibility of the coloring agent (C) in the adhesive tends to become good, and the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and easily satisfies the above-mentioned color difference ΔE. Furthermore, when the reactive group-containing monomer is a hydroxyl-containing monomer, when the content is 15% by mass or more, a predetermined amount of hydroxyl groups remain in the adhesive. The hydroxyl group is a hydrophilic group. When such a hydrophilic group is present in the adhesive in a predetermined amount, even if the adhesive is placed under high temperature and high humidity conditions, the compatibility with the water immersed in the adhesive under such high temperature and high humidity conditions Good, as a result, the whitening of the adhesive at the time of returning to normal temperature and humidity is suppressed (excellent heat and humidity resistance to whitening).

In addition, the (meth)acrylate polymer (A) may not contain a carboxyl group-containing monomer as a monomer unit constituting the polymer. Since the carboxyl group is an acid component, by not containing carboxylic acid monomers, even if there are problems caused by acid in the object to be attached to the adhesive, such as tin-doped indium oxide (ITO) and other transparent conductive films or metal films It can also suppress the problems (corrosion, resistance value change, etc.) caused by acid. However, it is allowed to contain a predetermined amount of carboxyl group-containing monomer to the extent that such a problem does not occur. Specifically, the (meth)acrylate polymer (A) is allowed to contain the carboxyl group-containing monomer as a monomer unit in an amount of 0.1% by mass or less, preferably 0.01% by mass or less, and more preferably 0.001% by mass or less.

The (meth)acrylate polymer (A) preferably contains alkyl (meth)acrylate as the monomer unit constituting the polymer. Therefore, good adhesion can be expressed. The alkyl group may be linear or branched.

From the viewpoint of adhesiveness, the alkyl (meth)acrylate is preferably an alkyl (meth)acrylate having 1 to 20 carbon atoms in the alkyl group. Alkyl (meth)acrylate having 1 to 20 carbon atoms, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate Ester, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-(meth)acrylate Decyl ester, n-dodecyl (meth)acrylate, tetradecyl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, etc. Among them, from the viewpoint of further improving the adhesiveness, alkyl (meth)acrylates having 1 to 8 carbon atoms in the alkyl group are preferred, and methyl (meth)acrylate, n-butyl (meth)acrylate, or (Meth) 2-ethylhexyl acrylate is particularly preferred, and methyl methacrylate, n-butyl acrylate, or 2-ethylhexyl acrylate is more preferred. These can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A) preferably contains 40% by mass or more of alkyl (meth)acrylate as a monomer unit constituting the polymer, particularly preferably 50% by mass or more, and more preferably 60% by mass or more good. When the lower limit of the content of the alkyl (meth)acrylate is the above, the (meth)acrylate polymer (A) can exhibit suitable adhesiveness. In addition, the dispersibility of the colorant (C) in the adhesive tends to be good, and the loss of the desired adhesiveness of the (meth)acrylate polymer (A) can be suppressed. Therefore, the obtained adhesive can exhibit suitable adhesiveness, has good reproducibility and uniformity of the above-mentioned optical properties, and easily satisfies the above-mentioned color difference ΔE. In addition, the (meth)acrylate polymer (A) preferably contains 99% by mass or less of alkyl (meth)acrylate as a monomer unit constituting the polymer, preferably 95% by mass or less, and contains 90 Mass% or less is particularly preferred, 85% by mass or less is more preferred, and 80% by mass or less is most preferred. When the upper limit of the content of alkyl (meth)acrylate is as described above, an appropriate amount of other monomer components such as monomers containing reactive functional groups can be introduced into the (meth)acrylate polymer (A) .

It is preferable that the said (meth)acrylate polymer (A) also contains the monomer (alicyclic structure containing monomer) which has an alicyclic structure in a molecule|numerator as a monomer unit which comprises this polymer. Due to the large volume of the alicyclic structure-containing monomer, it is presumed that the presence of the monomer in the polymer increases the distance between the polymers, so that the obtained adhesive can be made with excellent flexibility. Therefore, the adhesive has excellent step followability.

The carbocyclic ring of the alicyclic structure in the alicyclic structure-containing monomer may be a saturated structure, or may partially have an unsaturated bond. In addition, the alicyclic structure may be a monocyclic alicyclic structure or a polycyclic alicyclic structure such as bicyclic and tricyclic. From the viewpoint of making the distance between the obtained (meth)acrylate polymers (A) appropriate and imparting high stress relaxation properties via an adhesive, the above-mentioned alicyclic structure is a polycyclic alicyclic structure (polycyclic structure) Better. Furthermore, considering the compatibility of the (meth)acrylate polymer (A) with other components, the above-mentioned polycyclic structure is particularly preferably bicyclic to tetracyclic. In addition, from the same viewpoint of imparting stress relaxation properties as above, the carbon number of the alicyclic structure (that is, the total carbon number of the part forming the ring, if multiple rings exist independently, the total carbon number) is usually Above 5 is preferred, and above 7 is particularly preferred. On the other hand, the upper limit of the carbon number of the alicyclic structure is not particularly limited, and from the viewpoint of the same compatibility as described above, 15 or less is preferable, and 10 or less is particularly preferable.

Specific examples of the above-mentioned alicyclic structure-containing monomers include cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, adamantyl (meth)acrylate, isobornyl (meth)acrylate, (meth) ) Dicyclopentenyl acrylate, dicyclopentenyloxyethyl (meth)acrylate, etc., among them, dicyclopentyl (meth)acrylate (carbon of alicyclic structure) that exerts better step followability Number: 10), Adamantyl (meth)acrylate (carbon number of alicyclic structure: 10), or isocamyl (meth)acrylate (carbon number of alicyclic structure: 7) is preferred, especially (former (Base) Isobornyl acrylate is preferred, more preferably isobornyl acrylate. These may be used individually by 1 type, and may be used in combination of 2 or more types.

In the case where the (meth)acrylate polymer (A) contains an alicyclic structure-containing monomer as the monomer unit constituting the polymer, the alicyclic structure-containing monomer is preferably contained at 1% by mass or more, and 4% by mass The above is particularly preferable, and it is more preferable to contain 8% by mass or more. In addition, the (meth)acrylate polymer (A) preferably contains an alicyclic structure-containing monomer as a monomer unit constituting the polymer at 30% by mass or less, particularly preferably 22% by mass or less, and 14% by mass or less Better. When the content of the alicyclic structure-containing monomer is within the above range, the adhesive obtained has better step-following properties and better adhesion to plastics.

In addition, the (meth)acrylate polymer (A) preferably also contains a nitrogen atom-containing monomer as a monomer unit constituting the polymer. The presence of the nitrogen atom-containing monomer as a structural unit in the polymer can impart a predetermined polarity to the adhesive, and it can also have a good affinity for an adherend having a certain degree of polarity such as glass. From the viewpoint that the (meth)acrylate polymer (A) has moderate rigidity, the above-mentioned nitrogen atom-containing monomer is preferably a monomer having a nitrogen-containing heterocyclic ring. In addition, from the viewpoint of increasing the degree of freedom derived from the nitrogen atom-containing monomer portion in the high-level structure of the formed adhesive, the nitrogen atom-containing monomer is preferably used to form (meth)acrylate polymerization Except for the one polymerizable group used in the polymerization of the substance (A), one that does not contain a reactive unsaturated double bond group.

Monomers with nitrogen-containing heterocycles such as N-(meth)acryloylmorpholine, N-vinyl-2-pyrrolidone, N-(meth)acryloylpyrrolidone, N-(methyl) Acrylic piperidine, N-(meth)acrylic pyrrolidine, N-(meth)acrylic aziridine, aziridinyl ethyl (meth)acrylate, 2-vinyl pyridine, 4-vinylpyridine, 2-vinylpyrazine, 1-vinylimidazole, N-vinylcarbazole, N-vinylphthalimide, etc., among them, N-(methyl) ) Acrylic morpholine is preferred, and N-acrylic morpholine is particularly preferred. These may be used individually by 1 type, and may be used in combination of 2 or more types.

In the case where the (meth)acrylate polymer (A) contains a nitrogen atom-containing monomer as the monomer unit constituting the polymer, 1% by mass or more of the nitrogen atom-containing monomer is preferable, and 4% by mass or more is particularly preferable , More preferably 8 mass% or more. In addition, the (meth)acrylate polymer (A) contains the nitrogen atom-containing monomer as a monomer unit constituting the polymer, preferably 20% by mass or less, particularly preferably 16% by mass or less, and more preferably 12% by mass or less . When the content of the nitrogen atom-containing monomer is in the above range, the obtained adhesive can fully exhibit excellent adhesion to glass.

The (meth)acrylate polymer (A) may optionally contain other monomers as monomer units constituting the polymer. In order not to impair the aforementioned functions of the reactive functional group-containing monomer, other monomers are preferably monomers that do not contain a reactive functional group. Such monomers include, for example, alkoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, and other alkoxyalkyl (meth)acrylates, vinyl acetate, styrene, and the like. These can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A) is preferably a linear polymer. Since it is a linear polymer, entanglement of molecular chains easily occurs, and improvement in cohesive force can be expected. Therefore, the obtained adhesive easily exhibits a suitable gel fraction, adhesive force, etc., and is likely to be excellent in step followability and foam resistance under high temperature and high humidity conditions.

In addition, the (meth)acrylate polymer (A) is preferably a solution polymer obtained by a solution polymerization method. Since it is a solution polymer, it is easy to obtain a high molecular weight polymer, and an improvement in cohesive force can be expected. Therefore, the obtained adhesive easily exhibits a suitable gel fraction, adhesive force, etc., and is likely to be excellent in step followability and foam resistance under high temperature and high humidity conditions.

The polymerization state of the (meth)acrylate polymer (A) may be a random copolymer or a block copolymer.

The lower limit of the weight average molecular weight of the (meth)acrylate polymer (A) is preferably 200,000 or more, particularly preferably 300,000 or more, and more preferably 400,000 or more. From the viewpoint of the dispersibility of the colorant (C), More than 450,000 is better. When the lower limit of the weight average molecular weight of the (meth)acrylate polymer (A) is the above, the gel fraction or the adhesive force of the obtained adhesive is likely to be suitable, and it becomes a high temperature and high humidity condition. The following is better in step following or blistering resistance. In addition, the colorant (C) tends to have good dispersibility in the adhesive. Therefore, the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and easily satisfies the above-mentioned color difference ΔE.

In addition, the upper limit of the weight average molecular weight of the (meth)acrylate polymer (A) is preferably 2 million or less, preferably 1.5 million or less, particularly preferably 1 million or less, and even more preferably 800,000 or less. From the viewpoint of high adhesion, 650,000 or less is better. When the upper limit value of the weight average molecular weight of the (meth)acrylate polymer (A) is as described above, the obtained value of the gel fraction of the adhesive is likely to be suitable, and the initial step followability becomes The better. In addition, the weight average molecular weight in this specification is a value in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method.

Moreover, in the adhesive composition P, (meth)acrylate polymer (A) may be used individually by 1 type, and may be used in combination of 2 or more types.

(1-2) Crosslinking agent (B) The crosslinking agent (B) can crosslink the (meth)acrylate polymer (A) by heating the adhesive composition P, and can form a three-dimensional network structure well. Therefore, the cohesive force of the obtained adhesive is improved, and it is excellent in step followability and foam resistance under high temperature and high humidity conditions.

The crosslinking agent (B) only needs to be reactive with the reactive group of the (meth)acrylate polymer (A), such as isocyanate crosslinking agent, epoxy crosslinking agent, amine crosslinking agent , Melamine crosslinking agents, aziridine crosslinking agents, diamine crosslinking agents, aldehyde crosslinking agents, azoline crosslinking agents, metal alkoxide crosslinking agents, metal chelating agents Linking agents, metal salt crosslinking agents, ammonium salt crosslinking agents, etc. Among the above, when the reactive group of the (meth)acrylate polymer (A) is a hydroxyl group, it is preferable to use an isocyanate-based crosslinking agent having excellent reactivity with the hydroxyl group. When the reactive group of the polymer (A) is a carboxyl group, it is better to use an epoxy-based crosslinking agent having excellent reactivity with the carboxyl group. Moreover, the crosslinking agent (B) may be used individually by 1 type, and may be used in combination of 2 or more types.

The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. Polyisocyanate compounds, for example, aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, xylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diisocyanate Alicyclic polyisocyanates such as phenylmethane diisocyanate, etc., and the biuret, isocyanurate, and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil The adducts of the reactants of such small molecules containing active hydrogen compounds. Among them, from the viewpoint of reactivity with hydroxyl groups, trimethylolpropane-modified aromatic polyisocyanates, especially trimethylolpropane-modified toluene diisocyanate and trimethylolpropane-modified xylene diisocyanate are good.

Epoxy crosslinking agent, for example, 1,3-bis(N, N-diglycidylaminomethyl)cyclohexane, N, N, N', N', -tetraepoxypropyl- m-xylene diamine, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, Diglycidylamine and so on. Among them, from the viewpoint of reactivity with a carboxyl group, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane is preferred.

In the adhesive composition P, the content of the crosslinking agent (B) relative to 100 parts by mass of the (meth)acrylate polymer (A) is preferably 0.01 parts by mass or more, particularly preferably 0.03 parts by mass or more, and 0.05 parts by mass More than one serving is better. Moreover, the content is preferably 10 parts by mass or less, preferably 5 parts by mass or less, particularly preferably 1 part by mass or less, and more preferably 0.4 parts by mass or less. When the content of the crosslinking agent (B) is in the above range, the obtained adhesive exerts good cohesive force, and the gel fraction or adhesive force is easy to become a suitable one, and becomes a step follower under high temperature and high humidity conditions. The ones with better performance and blistering resistance.

(1-3) Coloring agent (C) The colorant (C) may be a pigment or a dye. The dye can be an inorganic pigment or an organic pigment. From the viewpoint of durability of the obtained adhesive, inorganic pigments are preferred. The color of the coloring agent is selected to have a color difference ΔE within the above range. Generally, dark or dark colors such as black, brown, dark blue, purple, and blue are preferred, and black is particularly preferred.

Inorganic pigments, such as carbon black, cobalt pigments, iron pigments, chromium pigments, titanium pigments, vanadium pigments, zirconium pigments, molybdenum pigments, ruthenium pigments, platinum pigments, ITO (indium tin oxide) Pigments, ATO (antimony tin oxide) pigments, etc.

In addition, organic pigments and organic dyes, for example, aminium-based pigments, cyanine-based pigments, merocyanine-based pigments, croconium-based pigments, squaraine (Squarylium) pigments, azulenium pigments, polymethine pigments, naphthoquinone pigments, pyrylium pigments, phthalocyanine pigments, naphthalocyanines Naphthalocyanine pigments, naphtholactam pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene ) Pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, quinophthalone pigments, pyrrole pigments, Thioindigo pigments, metal complex pigments (metal complex salt dyes), dithiol metal complex pigments, indophenol pigments, triarylmethane pigments, anthraquinone ( anthraquinone pigments, dioxazine pigments, naphthol pigments, azomethine pigments, benzimidazolone pigments, pyranthrone pigments and Reduction class (threne) color, etc.

Black pigments include, for example, carbon black, copper oxide, ferroferric oxide, manganese dioxide, aniline black, activated carbon and the like. In addition, black dyes include high-concentration vegetable dyes or azo dyes.

In addition, the above-mentioned pigments or dyes may be appropriately mixed and used depending on the purpose.

From the viewpoint of color difference ΔE, carbon black, nigrosine-based black dyes, and chromate-based black dyes are preferable among the above-mentioned colorants. In addition, the surface of carbon black may be subjected to a predetermined treatment (for example, a solvophilization treatment) or not.

The above-mentioned colorant, a liquid diluted 10,000 times with ethyl acetate, the average haze value of the average value of the haze value at a wavelength of 780nm and the haze value at a wavelength of 380nm, the lower limit is 1% or more The better is better, the better is more than 2%, the better is more than 3%. In addition, the upper limit of the average haze value of the colorant is preferably 60% or less, preferably 40% or less, particularly preferably 30% or less, more preferably 20% or less, and most preferably 10% or less . By using an appropriate amount of such a coloring agent, the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and can easily satisfy the above-mentioned color difference ΔE.

In addition, for the colorant, the colorant is a liquid diluted 10,000 times with ethyl acetate, the difference between the haze value at a wavelength of 780nm and the haze value at a wavelength of 380nm is preferably 30 points or less, and 25 points The following is preferable, 20 points or less is particularly preferable, 16 points or less is more preferable, and 10 points or less is most preferable. By using an appropriate amount of such a coloring agent, the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and can easily satisfy the above-mentioned color difference ΔE.

In addition, the lower limit of the difference in the haze value may be 0 point, but from the viewpoint of easy adjustment of the optical properties of the adhesive layer 11, it is preferably 0.1 point or more, 0.5 point or more, and More than 1 point is particularly preferred, and more than 3 points is more preferred.

The colorant is a liquid diluted 10,000 times with ethyl acetate. The haze value at a wavelength of 780nm is preferably 0.1-50%, 0.5-40% is preferred, 1-30% is particularly preferred, and 1.5-20% is more preferred. 2～10% is best. In addition, the colorant is a liquid diluted 10,000 times with ethyl acetate. The haze value at a wavelength of 380nm is preferably 1-60%, preferably 3-50%, particularly preferably 6-40%, and more preferably 8-30%. Good, 10-20% is the best. Therefore, it is easy to satisfy the above difference in haze value.

In addition, the colorant is a liquid diluted 10,000 times with ethyl acetate, and the haze of each wavelength (ie, 380nm, 385nm, 390nm, ･･･, 775nm, 780nm) in the 5nm interval of the wavelength region of 380-780nm The standard deviation of the value is preferably 10 or less, preferably 8 or less, particularly preferably 5 or less, and more preferably 2 or less. The lower limit of the above standard deviation is preferably 0, but usually 0.1 or more is preferred, 0.5 or more is particularly preferred, and 1 or more is more preferred. Therefore, the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and can easily satisfy the above-mentioned color difference ΔE.

The content of the colorant (C) in the adhesive composition P is preferably 0.001 parts by mass or more, preferably 0.005 parts by mass or more, 0.01 parts by mass relative to 100 parts by mass of the (meth)acrylate polymer (A) The above is particularly preferred, more preferably 0.02 parts by mass or more, and most preferably 0.03 parts by mass or more. When the lower limit of the content of the colorant (C) is the above, the value that can adjust the total light transmittance is low to a predetermined level, and the color difference ΔE is easily satisfied. Furthermore, the above content is preferably 1.3 parts by mass or less, preferably 1.0 parts by mass or less, particularly preferably 0.4 parts by mass or less, more preferably 0.3 parts by mass or less, and most preferably 0.15 parts by mass or less. When the upper limit of the content of the coloring agent (C) is as described above, the obtained adhesive is likely to exhibit suitable optical properties, and it is easier to satisfy the chromatic aberration ΔE and the total light transmittance.

(1-4) Active energy ray hardening component (D) In the adhesive formed by cross-linking the adhesive composition P with active energy rays, the active energy ray curable component (D) is polymerized with each other, and the polymerized active energy ray curable component (D) is entangled It is the cross-linked structure (stereo network structure) of (meth)acrylate polymer (A). Adhesives with such a high-level structure exhibit very good durability and become particularly excellent in step following and foaming resistance under high temperature and high humidity conditions.

The active energy ray curable component (D) is not particularly limited as long as it is cured by active energy ray irradiation to obtain the above-mentioned effects, and it may be any of monomers, oligomers, or polymers, or these mixture. Among them, for example, a polyfunctional acrylate monomer having more excellent foam resistance can be preferred.

Multifunctional acrylate monomers such as 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylic acid Esters, polyethylene glycol di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, hydroxytrimethyl acetate neopentyl glycol di(meth)acrylate, dicyclopentyl Di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, caprolactone modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified di(methyl) phosphate ) Acrylate, bis(acryloxyethyl) isocyanurate, allylated cyclohexyl di(meth)acrylate, ethoxylated bisphenol A diacrylate, 9,9-bis[ 4-(2-propenyloxyethoxy)phenyl] fluorene and other bifunctional groups; trimethylolpropane tri(meth)acrylate, dineopentyl erythritol tri(meth)acrylate, Propionic acid modified dineopentaerythritol tri(meth)acrylate, neopentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, ginseng (propylene) (Oxyethyl) isocyanurate, ε-caprolactone modified ginseng-(2-(meth)acryloxyethyl) isocyanurate, etc. trifunctional type; diglycerol tetra 4-functional type such as (meth)acrylate and neopentylerythritol tetra(meth)acrylate; 5-functional type such as propionic acid-modified dineopentaerythritol penta(meth)acrylate; two new 6-functional type such as pentaerythritol hexa(meth)acrylate, caprolactone modified dineopentaerythritol hexa(meth)acrylate, etc. These may be used individually by 1 type, and may be used in combination of 2 or more types. From the viewpoint of compatibility with the (meth)acrylate polymer (A), the polyfunctional acrylate monomer is preferably one having a molecular weight of less than 1,000.

Among the above, from the viewpoint of the foam resistance of the obtained adhesive, bis(acryloxyethyl) isocyanurate, ginseng (acryloxyethyl) isocyanurate, ε- Caprolactone modified ginseng-(2-(meth)acryloyloxyethyl) isocyanurate and other multifunctional acrylate monomers containing isocyanurate structure in the molecule, or tricyclic Polyfunctional acrylate monomers such as decane dimethanol (meth)acrylate and the like that contain a cyclic structure (especially a cycloalkane structure) in the molecule are preferred, with three or more functional groups and isocyanurea in the molecule A polyfunctional acrylate monomer with an acid ester structure, or a polyfunctional acrylate monomer with more than two functional groups and a polycyclic structure (especially a cycloalkane polycyclic structure) in the molecule is preferable, and ε －Caprolactone modified ginseng－(2-(meth)acryloyloxyethyl) isocyanurate or tricyclodecane dimethanol (meth)acrylate is particularly preferred, and ε-caprolactone Ester-modified ginseng-(2-acryloyloxyethyl) isocyanurate or tricyclodecane dimethanol acrylate is more preferable, and ε-caprolactone-modified ginseng-(2-acryloyloxy) (Ethyl) isocyanurate is the best.

In the adhesive composition P, the content of the active energy ray curable component (D) relative to 100 parts by mass of the (meth)acrylate polymer (A), the lower limit is preferably 1 part by mass or more, 3 parts by mass The above is particularly good, more preferably 4 parts by mass or more. On the other hand, from the viewpoint of the adhesive force of the adhesive after curing by active energy rays, the upper limit of the above content is preferably 20 parts by mass or less, particularly preferably 12 parts by mass or less, and more preferably 10 parts by mass or less. From the viewpoint of higher adhesion, 9 parts by mass or less is preferable. When the content of the curable component (D) through active energy rays is within the above range, the adhesive after the active energy rays is hardened is likely to make the gel fraction or adhesive force suitable for the value, which becomes a step difference under high temperature and high humidity conditions Those with better followability and blistering resistance.

(1-5) Photopolymerization initiator (E) When ultraviolet rays are used as the active energy ray for curing the adhesive composition P, the adhesive composition P preferably contains a photopolymerization initiator (E). By containing such a photopolymerization initiator (E), the active energy ray curable component (D) can be efficiently polymerized, and the polymerization curing time and the irradiation amount of the active energy ray can be reduced.

Such a photopolymerization initiator (E), for example, benzoin (benzoin), benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone (Acetophenone), dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxyl -2-Methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl- Propan-1-one, 4-(2-hydroxyethoxy) phenyl-2-(hydroxy-2-propyl) ketone, benzophenone, p-phenyl diphenyl ketone, 4, 4'-Diethylamino diphenyl ketone, dichloro diphenyl ketone, 2-methylanthraquinone, 2-ethyl anthraquinone, 2-tertiary butyl anthraquinone, 2-amino anthraquinone, 2-methyl thioxanthone (2-methyl thioxanthone), 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone , Benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylamino benzoate, oligo[2-hydroxy-2-methyl-1-[4-(1-methyl) Vinyl group) phenyl] acetone], 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzyl)-benzene Phosphine oxides, etc. These can be used individually or in combination of 2 or more types.

In the adhesive composition P, the content of the photopolymerization initiator (E) relative to 100 parts by mass of the active energy ray curable component (D), the lower limit is preferably 0.1 part by mass or more, and particularly preferably 1 part by mass or more , 5 parts by mass or more is more preferable. In addition, the upper limit is preferably 30 parts by mass or less, particularly preferably 20 parts by mass or less, and more preferably 12 parts by mass or less.

(1-6) Various additives Various additives commonly used in acrylic adhesives, such as silane coupling agents, rust inhibitors, ultraviolet absorbers, antistatic agents, tackifiers, antioxidants, light stabilizers, and softeners, can be added to the adhesive composition P as needed. , Refractive index adjuster, etc. In addition, the additives constituting the adhesive composition P do not contain the polymerization solvent or the dilution solvent described later.

Among the above, the adhesive composition P preferably contains a silane coupling agent. Therefore, even if the adherend is a plastic plate or a glass element, the adhesion to the adherend can be increased, and the step followability and blistering resistance under high temperature and high humidity conditions can be better.

The silane coupling agent is an organosilicon compound having at least one alkoxysilyl group in the molecule, and is preferably compatible with the (meth)acrylate polymer (A) and has light transmittance.

Such silane coupling agents, for example, vinyl trimethoxy silane, vinyl triethoxy silane, methacryloxy propyl trimethoxy silane, and other silicon compounds containing polymerizable unsaturated groups; 3-epoxy Silicon compounds with epoxy structure such as propoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc.; 3-mercaptopropyltrimethoxysilane, 3 -Mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane and other mercapto group-containing silicon compounds; 3-aminopropyltrimethoxysilane, N-(2-aminoethyl) )-3-Aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane and other amino-containing silicon compounds; 3-chloropropane Trimethoxysilane, 3-isocyanate propyltriethoxysilane; or at least one of these and methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, ethyltrimethyl Condensates of alkyl-containing silicon compounds such as oxysilane. These may be used individually by 1 type, and may be used in combination of 2 or more types.

The content of the silane coupling agent in the adhesive composition P, relative to 100 parts by mass of the (meth)acrylate polymer (A), is preferably 0.01 parts by mass or more, particularly preferably 0.05 parts by mass or more, and more preferably 0.1 parts by mass or more good. In addition, the content is preferably 1 part by mass or less, particularly preferably 0.5 parts by mass or less, and more preferably 0.3 parts by mass or less.

(2) Preparation of adhesive composition The adhesive composition P can be produced by manufacturing (meth)acrylate polymer (A), mixing the obtained (meth)acrylate polymer (A), crosslinking agent (B), and coloring agent (C), and It is manufactured by adding active energy ray curable component (D), photopolymerization initiator (E), additives, etc. as needed.

The (meth)acrylate polymer (A) can be produced by polymerizing a mixture of monomers constituting the polymer by a general radical polymerization method. The polymerization of the (meth)acrylate polymer (A) is preferably carried out by a solution polymerization method using a polymerization initiator as necessary. However, the present invention is not limited to these, and polymerization may be carried out without solvent. A polymerization solvent, for example, ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone, etc., can also use 2 or more types together.

The polymerization initiator, for example, an azo compound, an organic peroxide, etc., may be used in combination of two or more kinds. Azo compounds, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane 1- Carbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile), Dimethyl 2,2'-azobis(2-methylpropyl), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-hydroxymethyl) Base propionitrile), 2,2'-azobis[2-(2-imidazoline-2-yl)propane], etc.

Organic peroxides such as benzoyl peroxy, t-butyl peroxybenzoate, cumene hydroperoxy, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, peroxy Di(2-ethoxyethyl) dicarbonate, t-butyl peroxyneodecanoate, t-butyl peroxybivalate, (3,5 , 5-Trimethylhexyl peroxide, dipropionyl peroxide, diacetyl peroxide, etc.

Moreover, in the above-mentioned polymerization step, the weight average molecular weight of the obtained polymer can be adjusted by formulating a chain transfer agent such as 2-mercaptoethanol.

After obtaining the (meth)acrylate polymer (A), add the crosslinking agent (B), the coloring agent (C), and if necessary, the diluent solvent and active agent to the solution of the (meth)acrylate polymer (A) The energy-ray curable component (D), photopolymerization initiator (E), additives, etc., are thoroughly mixed to obtain an adhesive composition P (coating solution) diluted with a solvent. In addition, in the case of any of the above components, when a solid substance is used, or when they are mixed with other components in an undiluted state, the components can be dissolved or diluted in a dilution solvent beforehand, and then mixed with other components. .

As the above-mentioned dilution solvent, for example, aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and vinyl chloride; methanol, ethanol, propanol, butane Alcohols, 1-methoxy-2-propanol, etc.; ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, cyclohexanone, etc.; ethyl acetate, butyl acetate, etc. Esters; Cellosolve solvents such as ethyl cellosolve.

The concentration and viscosity of the coating solution prepared in this way are not particularly limited as long as the coating solution can be coated, and can be selected appropriately depending on the situation. For example, the concentration of the adhesive composition P is diluted to 10 to 60% by mass. In addition, when the coating solution is obtained, the addition of a diluted solution or the like is not an essential condition, and if the adhesive composition P has a coatingable viscosity or the like, the dilution solvent may not be added. In this case, the adhesive composition P is a coating solvent in which the polymerization solvent of the (meth)acrylate polymer (A) is directly used as the dilution solvent.

(3) Formation of adhesive layer The adhesive layer 11 of this embodiment is preferably formed of an adhesive that crosslinks the adhesive composition P (the coating layer). The crosslinking of the adhesive composition P can usually be performed by heat treatment. In addition, this heat treatment can also be performed together with the drying treatment when the coating layer of the adhesive composition P applied to the desired object is volatilized with a dilution solvent.

The heating temperature of the heat treatment is preferably 50 to 150°C, particularly preferably 70 to 120°C. The heating time is preferably 10 seconds to 10 minutes, and 50 seconds to 2 minutes is particularly good.

After the heat treatment, an aging period of about 1 to 2 weeks at normal temperature (for example, 23° C., 50% RH) may be provided as necessary. In the case where this aging period is necessary, the adhesive is formed after the aging period, and in the case where the aging period is not required, the adhesive is formed after the heat treatment is completed.

Through the above-mentioned heat treatment (and aging), the (meth)acrylate polymer (A) is fully crosslinked through the crosslinking agent (B). The adhesive thus obtained has a value that easily satisfies the desired gel fraction, adhesive force, etc., and is excellent in step followability and foam resistance under high temperature and high humidity conditions.

(4) The physical properties of the adhesive (gel fraction) In this embodiment, the lower limit of the gel fraction of the adhesive is preferably 20% or more, preferably 25% or more, and particularly preferably 30% or more. When the lower limit of the gel fraction of the adhesive is the above, the cohesive force of the adhesive increases, and it becomes one having better step followability under high temperature and high humidity conditions. In addition, the upper limit of the gel fraction of the adhesive of this embodiment is preferably 100% or less, preferably 90% or less, particularly preferably 80% or less, and more preferably 70% or less. When the upper limit value of the gel fraction of the adhesive is the above, the adhesive will not be too hard, and will be the one that is excellent in both the initial step followability and the durable step followability. In addition, it becomes the one that exhibits good adhesion and has better adhesion to the adherend. Here, the method of measuring the gel fraction of the adhesive is as shown in the test example described later.

In the case of an active energy ray curable adhesive, the lower limit of the gel fraction of the adhesive after active energy ray curing is preferably 40% or more, 45% or more is preferred, 50% or more is particularly preferred, and 62% The above is the best. In addition, the upper limit of the gel fraction is preferably 100% or less, preferably 95% or less, particularly preferably 90% or less, and more preferably 85% or less. When the gel fraction of the adhesive after curing by active energy rays is in the above range, it is better in step followability and foam resistance under high temperature and high humidity conditions. In addition, it becomes the one that exhibits good adhesion and has better adhesion to the adherend.

(5) The thickness of the adhesive layer The lower limit of the thickness of the adhesive layer 11 is preferably 10 μm or more, preferably 25 μm or more, and particularly preferably 50 μm or more. When the lower limit of the thickness of the adhesive layer 11 is the above, the relationship between the transmission and the content of the coloring agent (C) can easily satisfy the above-mentioned optical properties, and furthermore, it is easy to exhibit the desired adhesive force. In addition, from the viewpoint of easily exhibiting excellent step followability, the lower limit is preferably 120 μm or more, preferably 140 μm or more, particularly preferably 160 μm or more, and more preferably 180 μm or more.

In addition, the upper limit of the thickness of the adhesive layer 11 is preferably 1000 μm or less, preferably 500 μm or less, particularly preferably 400 μm or less, and more preferably 300 μm or less. When the upper limit value of the thickness of the adhesive layer 11 is as mentioned above, it becomes a thing with good workability. In addition, appearance problems due to indentation are hard to occur. Furthermore, the relationship between the transmission and the content of the coloring agent (C), etc., easily satisfy the above-mentioned optical properties. In addition, the adhesive layer 11 may be formed as a single layer, or may be formed by stacking multiple layers.

In addition, the thickness of the adhesive layer 11 in the display body 2 is basically the same as the thickness of the adhesive layer 11 of the adhesive sheet 1 in this embodiment.

1－2. Peeling sheet The peeling sheets 12a, 12b protect the adhesive layer 11 to the time the adhesive sheet 1 is used, and are peeled off when the adhesive sheet 1 (adhesive layer 11) is used. In the adhesive sheet 1 of this embodiment, one or both of the release sheets 12a and 12b are not necessarily necessary.

The release sheets 12a, 12b use, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate Diester film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene vinyl acetate film, ionomer resin film, ethylene•(meth)acrylic acid copolymer film, ethylene •(Meth)acrylate copolymer film, polystyrene film, polycarbonate film, polyimide film, fluororesin film, etc. Moreover, these crosslinked films can also be used. Furthermore, these laminated films can also be used.

It is preferable to perform a peeling treatment on the peeling surface of the peeling sheet 12a, 12b (especially the surface contacting the adhesive layer 11). The release agent used in the release treatment, for example, alkyd, silicone, fluorine, unsaturated polyester, polyolefin, wax, etc. release agent. Furthermore, among the release sheets 12a, 12b, it is preferable that one release sheet is a heavy release type release sheet with a large release force, and the other release sheet is a light release type release sheet with a small release force.

The thickness of the release sheets 12a, 12b is not particularly limited, but is usually about 20 to 150 μm.

2. Physical properties (1) Haze value The haze value of the adhesive layer 11 is usually 0% or more. When the coloring agent (C) in the adhesive layer 11 is a dye, 0.01% or more is preferable, 0.05% or more is preferable, and 0.1% or more is particularly preferable . In addition, when the coloring agent (C) in the adhesive layer 11 is a pigment, the haze value of the adhesive layer 11 is preferably 0.1% or more, 0.5% or more is preferable, 1.0% or more is particularly preferable, and 1.5% or more More preferably, more than 3.0% is the best. Since the lower limit of the haze value of the adhesive layer 11 is the above, it is easy to satisfy the aforementioned color difference ΔE. On the other hand, the haze value of the adhesive layer 11 is preferably 80% or less, preferably 60% or less, particularly preferably 40% or less, and from the viewpoint of visibility, 30% or less is preferable, and 20% or less is most preferable. Since the upper limit of the haze value of the adhesive layer 11 is the above, it is easy to satisfy the above-mentioned total light transmittance and color difference ΔE. In addition, the haze value in this specification is a value measured based on JIS K7361:2000.

(2) Adhesion The lower limit of the adhesive force of the adhesive sheet 1 of this embodiment to the soda lime glass is preferably 3N/25mm or more, preferably 5N/25mm or more, particularly preferably 10N/25mm or more, and more preferably 20N/25mm or more. When the lower limit of the adhesive force is the above, it is better in step followability and blistering resistance under high temperature and high humidity conditions. In addition, the upper limit of the adhesive force of the adhesive sheet 1 of this embodiment to the soda lime glass is preferably 100N/25mm or less, preferably 90N/25mm or less, and particularly preferably 70N/25mm or less. When the upper limit of the adhesive force is the above-mentioned value, good reworkability can be obtained, and when a bonding error occurs, it becomes possible to reuse the display component, especially the expensive display component.

Here, the adhesive force in this manual is basically the adhesive force measured by the 180 degree peeling method according to JIS Z0237:2009, but the measurement sample is 25mm wide and 100mm long, and the measurement sample is attached to the adherend to After applying pressure at 0.5 MPa and 50°C for 20 minutes, leave it under normal pressure, 23°C, and 50% RH for 24 hours, and measure at a peeling speed of 300 mm/min. In addition, in the case of an active energy ray-curable adhesive, it refers to the adhesive force of the adhesive layer on which the active energy ray hardens after being attached to the adherend.

3. Manufacture of adhesive sheet An example of the production of the adhesive sheet 1 is to apply the above-mentioned coating solution of the adhesive composition P to the release surface of a release sheet 12a (or 12b), and heat-process the adhesive composition P to thermally crosslink the adhesive composition P to form After the coating layer, the coating layer and the release surface of the other release sheet 12b (or 12a) are laminated. In the case where the aging period is necessary, after the aging period, and when the aging period is not required, the above-mentioned coating layer directly becomes the adhesive layer 1. Thus, the above-mentioned adhesive sheet 1 was obtained. The conditions for heat treatment and maturation are as described above.

Another example of the production of the adhesive sheet 1 is to apply the above-mentioned coating solution of the adhesive composition P to the release surface of a release sheet 12a, and heat-treat the adhesive composition P to thermally crosslink the adhesive composition P to form a coating layer. A release sheet 12a with a coating layer was obtained. In addition, on the peeling surface of the other peeling sheet 12b, the coating solution of the adhesive composition P is applied, and heat treatment is performed to thermally crosslink the adhesive composition P to form a coating layer to obtain a coating layer.的release sheet 12b. After that, the release sheet 12a with a coating layer and the release sheet 12b with a coating layer are bonded together so that both coating layers are in contact with each other. Here, it is also possible to produce a plurality of release sheets with coating layers, and to bond the coating layers by a desired number. In the case where the aging period is necessary, after the aging period, and when the aging period is not required, the above-mentioned laminated coating layer directly becomes the adhesive layer 11. Thus, the above-mentioned adhesive sheet 1 was obtained. According to this manufacturing example, even when the adhesive layer 11 is thick, stable manufacturing is possible.

As a method of applying the coating solution of the adhesive composition P, for example, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, etc. can be used.

[Manufacture of display body] In the manufacture of the above-mentioned display body 2, one example is to peel off a release sheet 12a of the adhesive sheet 1, and bond the exposed adhesive layer 11 of the adhesive sheet 1 to the side surface where the printed layer 3 of the first display body component 21 exists. .

After that, the other release sheet 12b is peeled from the adhesive layer 11 of the adhesive sheet 1, and the adhesive layer 11 exposed on the adhesive sheet 1 and the second display constituent element 22 are bonded together. In other examples, the order of bonding the first display component 21 and the second display component 22 may be exchanged.

In the case where the adhesive layer 11 is curable with active energy rays, the first display component 21 and the second display component 22 are bonded through the adhesive layer 11 as described above, and then the adhesive layer 11 is irradiated with active energy line. Therefore, the energy ray curable component (C) in the adhesive layer 11 is polymerized to harden the adhesive layer 11. Irradiation of the energy ray to the adhesive layer 11 is usually performed through either the first display component 21 or the second display component 22, preferably through the first display component 21 as a protective panel. get on.

Active energy rays refer to electromagnetic waves or charged particle rays that have energy quantum, such as ultraviolet rays or electron rays. Among the active energy rays, ultraviolet rays that are easy to handle are particularly preferred.

Ultraviolet radiation can be carried out via high-pressure mercury lamps, electrodeless H lamps, xenon lamps, etc. The illuminance of the ultraviolet radiation is preferably about 50-1000 mW/cm ^2, preferably about 100-500 mW/cm ² . In addition, the amount of light is preferably 50 to 10,000 mJ/cm ² , 200 to 7000 mJ/cm ² is more preferable, and 500 to 3000 mJ/cm ² is particularly preferable. On the other hand, the electron beam can be irradiated via an electron beam accelerator or the like, and the irradiation amount of the electron beam is preferably about 10 to 1000 krad.

The display body 2 having the adhesive layer 11 cured by irradiation with active energy rays as described above exhibits excellent blistering resistance. For example, if the display body 2 is placed under high-temperature and high-humidity conditions (for example, 85°C, 85% RH), even if the first display body constituent element 21 and/or the second display body constituent element 22 degas, it will be suppressed Blisters such as bubbles, floating, and peeling occur at the interface between the adhesive layer 11 and the display body constituent elements 21 and 22.

In addition, in the display 2 described above, when the adhesive layer 11 is formed of the adhesive composition P, the adhesive layer 11 has excellent step followability under high temperature and high humidity conditions. Therefore, even if the display body 2 is placed under, for example, high temperature and high humidity conditions (for example, 85° C., 85% RH), the occurrence of bubbles, floating, and peeling in the vicinity of the level difference is suppressed.

[Other displays] The display body of another embodiment of the present invention is shown in FIG. 3. The display body 2A of the embodiment of FIG. 3 has the same structure as the aforementioned display body 2, but the adhesive layer 11 is composed of a laminated body of a colored adhesive layer 111 and a colorless adhesive layer 112. In addition, the colorless adhesive layer 112 is located on the side in contact with the printed layer 3 of the convex portion in the first display component 21.

The colored adhesive layer 111 is the same as the adhesive layer 11 of the aforementioned display 2 and is colored by a colorant. On the other hand, the colorless adhesive layer 112 is not colored by the colorant, and is preferably colorless and transparent.

If the colored adhesive layer 111 is located on the side in contact with the printed layer 3 in the first display component 21, the colored adhesive layer 111 is compressed or deformed due to the unevenness of the printed layer 3. Therefore, the color of the colored adhesive layer 111 may be dark or light, and the transmittance may be uneven. For example, in the compressed portion of the colored adhesive layer 111, the color becomes darker, and the transmittance may decrease. In this regard, as described above, since the layer in contact with the printed layer 3 in the first display component 21 is the colorless adhesive layer 112, it is possible to prevent the colored adhesive layer 111 from being compressed or compressed due to the unevenness of the printed layer 3. Transformation. By doing so, it is possible to suppress the unevenness of the transmittance of the adhesive layer 11, improve the appearance quality of the display, and further improve the design.

The embodiments described above are described in order to facilitate the understanding of the present invention, and are not described in order to limit the present invention. Therefore, the requirements disclosed in the above-mentioned embodiments also include all design changes or equivalents belonging to the technical scope of the present invention.

For example, either or both of the release sheets 12a and 12b in the adhesive sheet 1 may be omitted, and desired optical elements may be laminated by replacing the release sheets 12a and/or 12b. In addition, the first display component 21 may not have the printed layer 3. In this case, an example of the display body 2 may have a frame material such as black at the edge. [Example]

Hereinafter, the present invention will be described in more detail with examples, but the scope of the present invention is not limited to these examples.

[Example 1] 1. Preparation of (meth)acrylate polymer 60 parts by mass of 2-ethylhexyl acrylate, 10 parts by mass of isobornyl acrylate, 10 parts by mass of N-acrylomorpholine, and 20 parts by mass of 2-hydroxyethyl acrylate were copolymerized by a solution polymerization method, Prepare (meth)acrylate polymer (A). When the molecular weight of this (meth)acrylate polymer (A) is measured by the method described later, the weight average molecular weight (Mw) is 500,000.

2. Modulation of adhesive composition 100 parts by mass of the (meth)acrylate polymer (A) obtained in step 1 above (solid content conversion value; the same below), the trimethylolpropane modified toluene diisocyanate (Toyo) of the crosslinking agent (B) Produced by Chem, product name "BHS8515") 0.2 parts by mass, colorant (C) carbon black pigment (C1) 0.04 parts by mass, active energy ray curable component (D) ε-caprolactone modified ginseng －(2-Acrylic oxyethyl) isocyanurate (D1; manufactured by Shinnakamura Chemical Co., Ltd., product name "NK Ester A-9300-1CL") 5.0 parts by mass, photopolymerization initiator (E) 0.5 parts by mass of a 1:1 mixture of 1-hydroxycyclohexyl phenyl ketone and benzophenone by mass, and 0.2 parts by mass of 3-glycidoxy propyl trimethoxy silane as a silane coupling agent, mix and stir thoroughly , Dilute with methyl ethyl ketone to obtain a coating solution of the adhesive composition.

Here, each formulation (solid content conversion value) of each adhesive composition when the (meth)acrylate polymer (A) is 100 parts by mass (solid content conversion value) is shown in Table 1. In addition, the details of the symbols and the like described in Table 1 are as follows. [(Meth)acrylate polymer (A)] 2EHA: 2-ethylhexyl acrylate IBXA: Isobornyl acrylate ACMO: N-acryloylmorpholine HEA: 2-hydroxyethyl acrylate MMA: methyl methacrylate BA: n-butyl acrylate AA: Acrylic [Crosslinking agent (B)] TDI: Trimethylolpropane modified toluene diisocyanate (manufactured by Toyo Chem, product name "BHS8515") XDI: Trimethylolpropane modified xylene diisocyanate (manufactured by Soken Chemical Co., Ltd., product name "TD-75") Epoxy: 1, 3-bis (N, N-diglycidylaminomethyl) cyclohexane (manufactured by Mitsubishi Gas Chemical Corporation, product name "TETRAD-C") [Colorant (C)] C1～C2: Carbon black black pigments with physical properties shown in Table 2 [Active energy ray hardening component (D)] D1: ε-caprolactone modified ginseng-(2-propylene oxyethyl) isocyanurate (manufactured by Shinnakamura Chemical Co., product name "NK Ester A-9300-1CL") D2: Tricyclodecane dimethanol diacrylate (manufactured by Shinnakamura Chemical Co., Ltd., product name "NK Ester A-DCP")

For liquids of C1～C2 coloring agents diluted 10,000 times with ethyl acetate, measure the haze using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "SH-7000", optical path 10mm) in accordance with JIS K7136: 2000 Degree value (%). From the measured value, calculate the difference between the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm, the average haze of the average value of the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm, at the wavelength The standard deviation of the haze value of each wavelength in the 5nm interval from 380nm to 780nm. The results are shown in Table 2.

3. Manufacture of adhesive sheet Apply the coating solution of the adhesive composition obtained in the above step 2 with a knife coater to a heavy peeling type release sheet that is peeled off with a silicone release agent on one side of the polyethylene terephthalate film (Lintec Corporation, product name "SP-PET752150") peeling treatment surface. After that, the coating layer was heated at 90° C. for 1 minute to form a coating layer (thickness: 50 μm), and a heavy release type release sheet with the coating layer was produced.

On the other hand, the coating solution of the adhesive composition obtained in the above step 2 is applied with a knife coater on the side of the polyethylene terephthalate film to be peeled off with a silicone release agent. The peel-off treatment surface of a peel-off peel sheet (manufactured by Lintec, product name "SP-PET382120"). After that, the coating layer was heated at 90° C. for 1 minute to form a coating layer (thickness: 50 μm), and 4 lightly peelable release sheets with the coating layer were produced.

The surface of the heavy release release sheet with a coating layer obtained above on the coating layer side and the surface of one of the light release release sheets with a coating layer obtained above on the coating layer side are pasted Together, a first layered product in which a coating layer with a thickness of 100 μm is sandwiched between a heavy release release sheet and a light release release sheet is obtained.

After that, the light release release sheet was peeled off from the first laminate, and the exposed surface of the exposed coating layer and the coating layer side of one of the light release release sheets with a coating layer obtained above The surface of the film was bonded together to obtain a second laminate in which a 150μm thick coating layer was sandwiched between the heavy release release sheet and the light release release sheet. The same steps as described above were repeated to obtain a fourth layered product in which a 250 μm-thick coating layer is sandwiched between the heavy release release sheet and the light release release sheet.

After that, the fourth layered product was aged at 23°C and 50% RH for 7 days to produce an adhesive formed by a heavy peeling release sheet/adhesive layer (thickness: 250μm)/light peeling release sheet. sheet.

In addition, the thickness of the adhesive layer is a value measured using a constant pressure thickness gauge (manufactured by Lintec, product name "PG-02") in accordance with JIS K7130.

[Examples 2 to 11, Comparative Examples 1 to 2] Except as shown in Table 1, the types and proportions of the monomers constituting the (meth)acrylate polymer (A), the weight average molecular weight (Mw) of the (meth)acrylate polymer (A), and the crosslinking agent ( B) type and blending amount, coloring agent (C) type and blending amount, active energy ray curable component (D) type and blending amount, photopolymerization initiator (E) blending amount, silane coupling agent Except for the blending amount and the thickness of the adhesive layer, the rest was the same as in Example 1 to produce an adhesive sheet. In addition, in Examples 6, 10, and 11, the thickness of the adhesive layer and the number of layers formed on the release sheet were changed to change the thickness of the adhesive layer.

The above-mentioned weight average molecular weight (Mw) is a weight average molecular weight in terms of polystyrene measured (GPC measurement) using gel permeation chromatography (GPC) under the following conditions. <Measurement conditions> ・GPC measuring device: made by Tosoh, HLC-8020 ・GPC column (pass in the following order): Tosoh Corporation TSK guard column HXL-H TSK glue GMHXL (×2) TSK glue G2000HXL ・Measuring solvent: Tetrahydrofuran ・Measurement temperature: 40°C

[Test Example 1] (Measurement of Gel Fraction) The adhesive sheets obtained in each of the Examples and Comparative Examples were cut into a size of 80mm×80mm, the adhesive layer was wrapped in a polyester mesh (mesh size 200), and the mass was weighed on a precision balance, subtracting the above The individual mass of the net is calculated only the mass of the adhesive. The mass at this time is M1.

After that, the adhesive wrapped in the polyester mesh was immersed in ethyl acetate for 24 hours at room temperature (23°C). After that, the adhesive was taken out and dried in air for 24 hours at a temperature of 23°C and a relative humidity of 50%, and then dried in an oven at 80°C for 12 hours. After drying, weigh its mass on a precision balance and subtract the individual mass of the net above to calculate the mass of only the adhesive. The mass at this time is M2. Gel fraction (%) is expressed as (M2/M1)×100. Therefore, the gel fraction of the adhesive (before UV irradiation) is derived. The results are shown in Table 3.

On the other hand, for the adhesive layer of the adhesive sheet obtained in the examples (except Example 7) and the comparative example, the light-peelable release sheet was irradiated with active energy rays (ultraviolet rays; UV) under the following conditions to make the adhesive Layer hardening. For the adhesive of the cured adhesive layer, the gel fraction is derived as described above (after UV irradiation). The results are shown in Table 3.

<Active energy ray irradiation conditions> ・Using high-pressure mercury lamp ・Illumination 200mW/cm ² , light intensity 2000mJ/cm ²・UV illuminance ・Light meter uses "UVPF-A1" made by Eye Graphics

[Test Example 2] (Measurement of total light transmittance) The adhesive layers of the adhesive sheets obtained in the examples and comparative examples were bonded to glass, and these were used as samples for measurement. In addition to the background measurement with glass, for the above-mentioned measurement samples, the total light transmittance (%) was measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "NDH-5000") in accordance with JIS K7361-1:1997 . The results are shown in Table 3.

[Test Example 3] (Measurement of Haze Value) For the adhesive layer of the adhesive sheet obtained in the Examples and Comparative Examples, the haze value (%) was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd., product name "NDH-5000") in accordance with JIS K7136:2000. The results are shown in Table 3.

[Test Example 4] (Measurement of L*a*b*) For the adhesive layer of the adhesive sheet obtained in the Examples and Comparative Examples, a simultaneous photometric spectrophotometer (manufactured by Nippon Denshoku Industries Co., Ltd., product name "SQ2000") was used to measure the transmitted light, CIE1976 L*a*b *Lightness L*(L*1), chromaticity a*(a*1), and chromaticity b*(b*1) specified by the color system. The results are shown in Table 3.

The surface of the first glass plate (manufactured by NSG Precision, product name "Corning glass Eagle XG", length 90mm×width 50mm×thickness 0.5mm) is screened in a frame shape (outer shape: length 90mm×width 50mm, width 5mm) Printing UV-curable ink (manufactured by Teikoku Ink, product name "POS-911 ink"). After that, irradiate ultraviolet rays (80W/cm ² , ² metal halide lamps, lamp height 15cm, belt rotation speed 10-15m/min) to harden the printed UV-curable ink, and produce a step caused by the printing layer. Difference (the height of the step difference: 10μm) glass plate with a printed layer.

After that, two polarizing plates are interposed with a transparent adhesive sheet (manufactured by Lintech, product name "OPTERIA MO-T015"), so that the polarization axis is in a cross-polarized state (polarization axis: ∠45°, ∠135°). Laminate to produce a first laminate composed of polarizing plate/transparent adhesive sheet/polarizing plate. Furthermore, a transparent adhesive sheet (manufactured by Lintech, product name "OPTERIA MO-T015") is interposed on the surface of a polarizing plate, and a second glass plate (manufactured by NSG Precision, product name "Corning glass Eagle XG") is interposed. ", 90mm in length × 50mm in width × 0.5mm in thickness) to produce a second laminate composed of polarizing plate/transparent adhesive sheet/polarizing plate/transparent adhesive sheet/glass plate. In addition, since the two polarizing plates are arranged in cross-polarized light, they are in an extinct state.

After cutting the adhesive sheets obtained in the Examples and Comparative Examples into a length of 90 mm × a width of 50 mm, the light-peelable release sheet was peeled from the adhesive sheet, and the exposed adhesive layer was bonded to the polarizing plate of the second laminate obtained above On the side, a third layered body is produced. Then, the heavy peeling type release sheet was peeled, and the said 3rd laminated body was bonded to the glass plate with a printing step so that the exposed adhesive layer may cover the whole surface of a frame-shaped printing layer. After that, the first glass plate was passed through, and under the same conditions as in Test Example 1, active energy rays were irradiated to harden the adhesive layer, and these were used as samples. In addition, Example 7 was in a state where active energy rays were not irradiated.

For the non-printed layer portion (equivalent to the display portion of the display body) and the printed layer portion (equivalent to the non-display portion of the display body) of the sample obtained above, a spectrophotometer (manufactured by BYK, product name) "Spectro guide"), for the reflected light of the incident light from the side of the first glass plate, measure the brightness L* (L*2) of the display unit specified by the CIE1976 L*a*b* color system, and the Chromaticity a*(a*2) and chromaticity b*(b*2) of the display part, lightness L*(L*3) of the non-display part, and chromaticity a*(a*3) of the non-display part And the chromaticity of the non-display area b*(b*3). The results are shown in Table 3.

From the above results, the color difference ΔE is calculated according to the following formula (I). The results are shown in Table 3.

[Test Example 5] (Measurement of Adhesion) The light-peelable release sheet was peeled from the adhesive sheets obtained in the Examples and Comparative Examples, and the exposed adhesive layer and a polyethylene terephthalate (PET) film with an easily bonding layer (manufactured by Toyobo Co., Ltd., product name " PET A4300", thickness: 100μm) easy-to-adhesive layer is bonded to obtain a laminate of heavy-peelable release sheet/adhesive layer/PET film. The obtained laminate was cut into 25 mm wide and 100 mm long, and these were used as samples.

In an environment of 23°C and 50% RH, the heavy-peelable release sheet was peeled from the above sample, and the exposed adhesive layer was pasted on soda lime glass (manufactured by Nippon Sheet Glass Co., Ltd.), and then used in an autoclave manufactured by Kurihara Manufacturing Co., Ltd. Press 0.5MPa and 50°C for 20 minutes. After that, it was left for 24 hours under the conditions of 23°C and 50% RH.

After that, the heavy peeling type peeling sheet was passed through, and active energy rays were irradiated under the same conditions as in Test Example 1 to harden the adhesive layer. In addition, the pressure-sensitive adhesive sheet of Example 7 was in a state not irradiated with active energy rays. After that, using a tensile tester (manufactured by Orientec, product name "Tensilon"), the adhesive force (N/25mm) was measured under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180 degrees. Except for conditions other than those described here, the measurement was performed in accordance with JIS Z0237:2009. The results are shown in Table 3.

[Test Example 6] (Evaluation of Appearance Coordination) In the sample obtained in Test Example 4, under a 3-wavelength fluorescent lamp (distance from the fluorescent lamp: 200cm), the non-printed layer portion (equivalent to the display portion of the display) and the printed layer portion (equivalent to Whether the non-display part in the display body is fused (with a sense of integrity), the appearance coordination is evaluated according to the following criteria. The results are shown in Table 3. ◎: The non-printing layer and the printing layer are very fused. ○: A certain degree of fusion between the non-printed layer and the printed layer. ×: The non-printing layer part and the printing layer part are obviously not fused.

[Test Example 7] (Evaluation of visibility) The adhesive sheets obtained in the Examples and Comparative Examples were cut into length 70 mm × width 70 mm, and the adhesive layer of the adhesive sheet was sandwiched between two soda lime glass plates (manufactured by Nippon Sheet Glass Co., Ltd., length 70 mm × width 70 mm × thickness 1.1 mm ) And fit. After that, the soda lime glass plate on one side was irradiated with active energy rays under the same conditions as in Test Example 1 to harden the adhesive layer, and these were used as samples. In addition, Example 7 was in a state where active energy rays were not irradiated.

On the other hand, in a monitor with a size of 15.6 inches and a resolution of 1366×768 (manufactured by Fujitsu, the product name "LITEBOOK A574/H"), the white background and black text (font: MS PGothic) are set from 5 to 20 points. The dot size (1 dot scale) is displayed at 100%.

On the above display, the samples obtained above are arranged. After that, at a distance of 50 cm from the display, confirm the size of the text that can be visually recognized, and evaluate the visibility based on the following criteria. The results are shown in Table 3. ◎: 6-point text can be visually recognized. ○: The 6-point text cannot be seen at all, but the 8-point text can be seen. △: The 8-point text cannot be seen at all, but the 15-point text can be seen. ×: The 15-point text cannot be seen.

[Test Example 8] (Evaluation of the level difference followability) The surface of the glass plate (manufactured by NSG Precision, product name "Corning glass Eagle XG", length 90mm×width 50mm×thickness 0.5mm) is frame-shaped (outer shape: Vertical 90mm × horizontal 50mm, width 5mm) screen printing UV-curable ink (manufactured by Teikoku Ink, product name "POS-911 ink"). After that, irradiate ultraviolet rays (80W/cm ² , ² metal halide lamps, lamp height 15cm, belt rotation speed 10-15m/min) to harden the printed UV-curable ink, and produce a step caused by the printing layer. Difference (the height of the step difference: 5μm, 10μm) with a stepped glass plate.

From the adhesive sheets obtained in the examples and comparative examples, the light-peelable release sheet was peeled off to expose the adhesive layer and the polyethylene terephthalate (PET) film with an easy-adhesion layer (manufactured by Toyobo Co., Ltd., product name) "PET A4300", thickness: 100μm) easy bonding layer bonding. After that, the re-peelable release sheet was peeled off to expose the adhesive layer. Next, using a laminator (manufactured by FUJIPLA, product name "LPD3214"), the laminate is laminated on each glass plate with a step so that the adhesive layer covers the entire frame-like printed surface. After that, after autoclave treatment under the conditions of 50°C and 0.5MPa for 20 minutes, it was left at normal pressure, 23°C, and 50% RH for 24 hours.

After that, the PET film was traversed, and under the same conditions as in Test Example 1, active energy rays were irradiated to harden the adhesive layer. Then, it was stored for 72 hours under humid heat conditions of 85°C and 85% RH. After that, the step followability is evaluated according to the following criteria. When the printing step is completely buried in the adhesive layer, the step followability is judged to be good, and when the interface between the printing step and the adhesive layer is floating or peeling, it is judged that it cannot follow the printing step . In addition, except that Example 7 was not irradiated with active energy rays, the rest was evaluated in the same manner as the above-mentioned method for step followability. The results are shown in Table 3. ◎: 10μm in print level is good ○: 5μm difference in printing is good ×: There is floating and peeling at the step difference of 5μm in printing

[Test Example 9] (Evaluation of resistance to foaming) From the adhesive sheets obtained in the Examples and Comparative Examples, the light-peelable release sheet was peeled off, and the exposed adhesive layer was bonded to a plastic board (manufactured by Mitsubishi Gas Chemical Co., Ltd., product name "Iupilon" with a PMMA layer laminated on a PC board). ˙Sheet MR58U", thickness: 0.7mm, containing UV absorber) on the PC board side to obtain a plastic board with an adhesive layer.

From the plastic board with the adhesive layer obtained above, peel off the heavy peeling type release sheet, and stick the plastic board to a 70mm×150mm soda-lime glass plate (manufactured by Nippon Plate Glass Co., Ltd., through the exposed adhesive layer) Thickness: 0.7mm). After that, it was treated in an autoclave at 50°C and 0.5 MPa for 20 minutes, and left at normal pressure, 23°C, and 50% RH for 24 hours. After that, the adhesive layer was traversed through the plastic plate, and under the same conditions as in Test Example 1, active energy rays were irradiated to harden the adhesive layer.

The obtained laminate was stored for 72 hours under high temperature and high humidity conditions of 85°C and 85% RH. After that, visually confirm the state of the interface between the adhesive layer and the adherend (plastic plate, glass plate), and evaluate the blistering resistance based on the following criteria. In addition, except that Example 7 was not irradiated with active energy rays, it was the same as the above, and the foaming resistance was evaluated. The results are shown in Table 3. ◎: No bubbles, floating, or peeling. ○: There is no floating or peeling, and bubbles are slightly generated, but there is no problem. △: There is no floating or peeling, but many bubbles are generated. ×: Floating and peeling occurred.

[Table 1] (Meth)acrylate polymer (A)) Crosslinking agent (B) Colorant (C) Active energy ray hardening component (D) Photopolymerization initiator (E) Silane coupling agent Adhesive layer thickness composition Mw species Mass parts species Mass parts species Mass parts Mass parts Mass parts μm Example 1 2EHA/IBXA/ACMO/HEA =60/10/10/20 500000 TDI 0.2 C1 0.04 D1 5 0.5 0.2 250 Example 2 TDI 0.2 C1 0.02 D1 5 0.5 0.2 250 Example 3 TDI 0.2 C2 0.2 D1 5 0.5 0.2 250 Example 4 TDI 0.2 C1 0.04 D1 5 0.5 - 250 Example 5 XDI 0.2 C1 0.04 D1 5 0.5 0.2 250 Example 6 TDI 0.2 C1 0.06 D1 5 0.5 0.2 150 Example 7 TDI 0.2 C1 0.04 - - - - 250 Example 8 TDI 0.2 C1 0.04 D2 5 0.5 0.2 250 Example 9 2EHA/MMA/HEA =65/15/20 700 thousand TDI 0.2 C1 0.04 D1 5 0.5 0.2 250 Example 10 BA/AA=90/10 400000 Epoxy 0.05 C1 0.04 D1 10 1 0.2 230 Example 11 2EHA/IBXA/ACMO/HEA =60/10/10/20 500000 TDI 0.2 C1 0.11 D1 5 0.5 0.2 100 Comparative example 1 TDI 0.2 - - D1 5 0.5 0.2 250 Comparative example 2 TDI 0.2 C2 1.5 D1 5 0.5 0.2 250

[Table 2] Types of colorants Haze value at wavelength 380nm (%) Haze value at wavelength 780nm (%) Difference of haze value (point) Average haze (%) Standard deviation of haze value C1 10.1 2.3 7.8 4.11 1.49 C2 25.0 23.7 1.3 24.89 0.48

[table 3] Gel fraction (%) Total light transmittance (%) Haze value (%) Adhesive layer Display Non-display part ΔE Adhesion (N/25 mm) Appearance coordination Visibility Step followability Foam resistance Before UV irradiation After UV irradiation L*1 a*1 b*1 L*2 a*2 b*2 L*3 a*3 b*3 Example 1 52 62 51.8 4.2 74.4 -1.5 1.2 2.39 0.34 -0.44 2.74 -0.17 -0.20 0.66 50≦ ◎ ◎ ◎ ◎ Example 2 53 63 74.5 4.3 89.9 -0.6 0.1 1.68 0.50 0.02 2.74 -0.17 -0.20 1.27 50≦ ○ ◎ ◎ ◎ Example 3 52 63 46.4 31.5 71.3 0.1 0.9 1.70 0.16 0.03 2.74 -0.17 -0.20 1.12 50≦ ◎ ○ ◎ ◎ Example 4 52 62 51.7 4.3 74.5 -1.5 1.2 2.40 0.33 -0.45 2.74 -0.17 -0.20 0.65 50≦ ◎ ◎ ◎ ◎ Example 5 51 62 50.9 4.6 74.6 -1.4 1.1 2.37 0.32 -0.42 2.74 -0.17 -0.20 0.65 50≦ ◎ ◎ ◎ ◎ Example 6 52 64 59.1 2.0 78.7 -1.7 -0.4 1.58 0.40 -0.49 2.74 -0.17 -0.20 1.32 50≦ ○ ◎ ○ ◎ Example 7 56 - 53.1 4.1 73.8 -1.5 1.3 2.50 0.35 -0.45 2.74 -0.17 -0.20 0.62 50≦ ◎ ◎ ◎ × Example 8 52 61 51.9 4.3 74.4 -1.4 1.2 2.38 0.34 -0.45 2.74 -0.17 -0.20 0.67 50≦ ◎ ◎ ◎ ○ Example 9 65 80 58.0 1.4 78.0 -1.7 -0.9 1.73 0.60 -0.34 2.74 -0.17 -0.20 1.28 25 ○ ◎ ◎ ◎ Example 10 55 70 62.0 0.9 80.2 -1.3 -1.1 1.03 0.20 0.06 2.74 -0.17 -0.20 1.77 38 ○ ◎ ◎ ◎ Example 11 52 63 51.5 4.0 74.2 -1.2 1.1 2.35 0.32 -0.42 2.74 -0.17 -0.20 0.66 45 ◎ ◎ × ◎ Comparative example 1 52 63 99≦ 0.2 96.9 -0.3 0.3 0.65 0.12 -0.38 2.74 -0.17 -0.20 2.12 50≦ × ◎ ○ ◎ Comparative example 2 51 58 0.3 92.3 0.1 -2.4 -0.8 2.01 0.16 0.08 2.74 -0.17 -0.20 0.85 50≦ ○ × ○ △

From Table 3, it can be seen that the adhesive sheets obtained in the examples are excellent in appearance coordination and visibility. In addition, the adhesive sheets obtained in Examples other than Example 11 were also excellent in step followability. Moreover, the use of the adhesive sheet obtained by the examples other than Example 7 also had excellent foaming resistance. [Industrial availability]

The adhesive sheet of the present invention can be suitably used, for example, for bonding a protective panel having a black printed layer and a desired display component.

1: Adhesive sheet 11: Adhesive layer 12a, 12b: peeling sheet 2, 2A: Display body 111: Colored adhesive layer 112: Colorless adhesive layer 21: The first display component 22: The second display component 3: Printing layer (convex part)

[Fig. 1] is a cross-sectional view of a display according to an embodiment of the present invention. [Figure 2] is a cross-sectional view of an adhesive sheet according to an embodiment of the present invention. [Fig. 3] is a cross-sectional view of a display body of another embodiment of the present invention.

11: Adhesive layer

2: display body

21: The first display component

22: The second display component

3: Printing layer (convex part)

Claims (10)

A display body having a display portion and a non-display portion, and at least one display body constituent element, other display body constituent elements, and an adhesive for bonding the above-mentioned one display body constituent element and the above-mentioned other display body constituent elements The display body of the agent layer is characterized in that the total light transmittance of the adhesive layer in the display portion is 3% or more, according to the CIE1976 L*a*b* color system, and the lightness of the display portion is L * Is L*2, the chromaticity a* of the display part is a*2, the chromaticity b* of the display part is b*2, the lightness L* of the non-display part is L*3, and the chromaticity of the non-display part is L*3. When the chromaticity a* is a*3 and the chromaticity b* of the non-display part is b*3, the color difference ΔE calculated by the following formula (I) is 2.00 or less

. Such as the display of claim 1, wherein L*3 of the non-display part is 0.1-50, a*3 of the non-display part is -20-20, and b*3 of the non-display part is -20-20 . Such as the display body of claim 1, wherein the non-display part is black. The display body of claim 1, wherein at least one of the one display body constituent element and the other display body constituent element has a convex portion on the surface of the adhesive layer side, The convex portion constitutes a part or all of the non-display portion. An adhesive sheet having an adhesive layer for bonding one of the display body constituent elements and the other display body constituent elements that constitute a display body having a display portion and a non-display portion, characterized in that the above-mentioned adhesive The total light transmittance of the agent layer is 3% or more, and the adhesive layer is colored to achieve the display body obtained by bonding the one display body constituent element and the other display body constituent element through the adhesive layer In accordance with the regulations of CIE1976 L*a*b* color system, the lightness L* of the display section is L*2, the chromaticity a* of the display section is a*2, and the chromaticity b* of the display section is When the lightness L* of the non-display part is L*3, the chromaticity a* of the non-display part is a*3, and the chromaticity b* of the non-display part is b*3, the following formula ( I) The calculated color difference ΔE is below 2.00

. Such as the adhesive sheet of claim 5, in which, according to the CIE1976 L*a*b* color system, the lightness L* of the adhesive layer is L*1, and the color a* of the adhesive layer is a* 1. When the color b* of the adhesive layer is b*1, the L*1 of the adhesive layer is 5 to 95, the a*1 of the adhesive layer is -20 to 20, and the b of the adhesive layer *1 is -20-20. Such as the adhesive sheet of claim 5, wherein the haze value of the adhesive layer is 0.1% or more and 80% or less. The adhesive sheet of claim 5, wherein the adhesive constituting the adhesive layer contains a coloring agent. The adhesive sheet of claim 8, wherein the colorant is a black pigment or dye. An adhesive sheet according to claim 5, which has two release sheets and the adhesive layer which is in contact with the release surfaces of the two release sheets and is sandwiched between the release sheets.

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