TW202035618A - Colored adhesive sheet and display apparatus capable of improving the sense of design of a display apparatus - Google Patents

Abstract

An object of the present invention is to provide a colored adhesive sheet capable of improving the sense of design of a display apparatus, and a display apparatus with improved sense of design. The solution of the present invention provides a colored adhesive sheet (1), which is provided with a colored adhesive layer (11) containing coloring agent for bonding a display apparatus constituent member and other display apparatus constituent members. The average haze of the colored adhesive layer (11) , which is an average value of the haze value at a wavelength of 780 nm and the haze value at a wavelength of 380 nm, is 1% or more and 60% or less.

Description

Colored adhesive sheet and display device

The present invention relates to a colored adhesive sheet that can be used to bond constituent members of a display device, and a display device using the colored adhesive sheet.

Display devices (displays) in recent years, such as automotive dashboards, car navigation systems, various meters installed in consoles, display devices such as in-vehicle display devices, display devices such as tablet terminals for general users, and commercial tablet terminals LCD devices are mostly used in display devices such as mobile phones and digital signage, and display devices such as outdoor digital signage.

In the above-mentioned display devices, including in-vehicle use, it is required that when the display device is turned off, it is required to exhibit a sense of integration with the peripheral components of the display device, such as frame materials, so as to improve the design. For this reason, it can be considered to color the display device. For example, Patent Documents 1 to 4 disclose inventions about coloring the display device. [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

[The problem to be solved by the invention]

However, the technologies disclosed in Patent Documents 1 to 4 mentioned above have different purposes of coloring, and cannot make the display device and the peripheral components exhibit a sense of unity, and improve the design.

The present invention is completed in view of the above-mentioned reasons, and aims to provide a colored adhesive sheet that can improve the design of a display device and a display device that can improve the design. [Means for solving problems]

In order to achieve the above objectives, firstly, the present invention provides a colored adhesive sheet, which is characterized in that it is provided with a coloring agent composed of a coloring agent-containing adhesive for bonding a display device constituent member and other display device constituent members. In the colored adhesive sheet of the adhesive layer, the average haze of the haze value of the colored adhesive layer at a wavelength of 780 nm and the average haze value at a wavelength of 380 nm is 1% or more and 60% or less (Invention 1).

According to the above invention (Invention 1), when the colored adhesive layer that satisfies the above physical properties is used in a display device, the design of the display device when the display device is turned off can be improved, especially the appearance coordination. For example, the display device can be given a sense of unity with peripheral members (especially black frame materials, etc.).

In the above invention (Invention 1), wherein the colored adhesive layer, the difference between the haze value at a wavelength of 780nm and the haze value at a wavelength of 380nm is preferably 15% or less (Invention 2).

In the above inventions (Inventions 1 and 2), it is preferable that the standard deviation of the haze value of the colored adhesive layer at 5 nm pitch in the wavelength region of 380 nm to 780 nm is 5 or less (Invention 3).

In the above inventions (Inventions 1 to 3), the total light transmittance of the colored adhesive layer is 10% or more and less than 95%, and the CIE1976L*a*b* color system of the colored adhesive layer is specified The chromaticity a* and chromaticity b* are preferably -7~7 (Invention 4).

In the above inventions (Inventions 1 to 4), wherein the colorant is a liquid diluted 10,000 times with ethyl acetate, and the average haze value of the average haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm, It is preferably 1% or more and 60% or less (Invention 5).

In the above invention (Inventions 1 to 5), wherein 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 30% or less Better (Invention 6).

In the above inventions (Inventions 1 to 6), the above-mentioned colorant is preferably a black pigment (Invention 7).

In the above inventions (Inventions 1 to 7), the above-mentioned adhesive is preferably an acrylic adhesive (Invention 8).

In the aforementioned inventions (Inventions 1 to 8), the aforementioned adhesive is used to crosslink an adhesive composition containing (meth)acrylate polymer (A), crosslinking agent (B), and coloring agent (C) The one is better (Invention 9).

In the above inventions (Inventions 1 to 9), it is preferable to include: two release sheets; and the colored adhesive layer connected to the release surfaces of the two release sheets and sandwiched between the release sheets (Invention 10) .

Second, the present invention provides a display device characterized in that it includes: a display device constituent member; other display device constituent members; and a display device constituent member and the other display device constituent members are bonded to each other In a display device with a colored adhesive layer, the colored adhesive layer is the colored adhesive layer of the colored adhesive sheet (Inventions 1 to 10) (Invention 11).

In the above invention (Invention 11), it is preferable that at least one of the above-mentioned one display device constituent member and the above-mentioned other display device constituent members has a step at least on the surface where the colored adhesive layer is bonded (Invention 12).

In the above inventions (Inventions 11 and 12), it is preferable to have a black frame material (Invention 13). [Effects of Invention]

According to the colored adhesive sheet of the present invention, the design of the display device can be improved. Furthermore, the display device of the present invention can be improved in design.

Hereinafter, embodiments of the present invention will be described. [Colored adhesive sheet] Regarding the colored adhesive sheet of one embodiment of the present invention, a colored adhesive layer composed of an adhesive containing a coloring agent for bonding a display device constituent member with other display device constituent members is preferably used in the colored adhesive It is formed by laminating release sheets on one or both sides of the agent layer. The display device and its components will be described later.

As an example of the colored adhesive sheet of this embodiment, the specific structure is shown in FIG. As shown in Figure 1, the colored adhesive sheet 1 is composed of two peeling sheets 12a, 12b, and the peeling surface connected to the two peeling sheets 12a, 12b, and the adhesive is sandwiched by 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 which is peeled and the surface which shows peelability even if a peeling process is not performed.

1. Each component 1-1. Colored adhesive layer With regard to the colored adhesive sheet 1 of the present embodiment, the average haze of the colored adhesive layer 11 at the wavelength of 780 nm and the average value of the haze at the wavelength of 380 nm is 1% or more and 60% or less. In addition, the haze value in this specification is a value measured in compliance with JIS K7136:2000.

When the adhesive layer 11 that satisfies the above physical properties is applied to a display device, when the display device is turned off, the design of the display device can be improved. As an example of this design, the appearance coordination at the time of turning off the lights can be cited. At this time, the display device can be given a sense of integrity with peripheral components, such as a black frame material, thereby exhibiting a sense of luxury. Specifically, by making the above-mentioned average haze above 1%, when the display device is turned off, the light incident on the screen of the display device is appropriately scattered, and the boundary between the display unit and its surrounding components can be made difficult to detect (no frame) . In this way, the overall sense of the display device and the surrounding components can be improved when the display device is turned off. On the other hand, by making the above-mentioned average haze below 60%, when the display device is turned off, whitening of the display device screen is suppressed, and the sense of integration with peripheral components is improved. That is, with the above average haze of 1% or more and 60% or less, the display device can be given a sense of integrity with the peripheral components when the display device is turned off, and an excellent appearance can be presented. According to the colored adhesive sheet 1 of this embodiment, the design of the display device can be improved in this way.

As the above-mentioned peripheral member, specifically, for example, an automobile instrument panel with a lightness L* of 23.2, a chromaticity a* of -0.5, and a chromaticity b* of -1.5 as specified by the CIE1976L*a*b* color system . As the hue of the above-mentioned peripheral components, lightness L* is 5~90, chroma a* is -40~40, and chroma b* is -40~40, especially lightness L* is 10~80. -30~30 for a*, -30~30 for chroma b*, 15~70 for lightness L*, a*-20~20 for chroma, -20~20 for chroma b* Better. Regarding the colored adhesive sheet 1 of the present embodiment, it can be suitably used for display devices having peripheral members of the above-mentioned color tone.

The above-mentioned average haze should be 1% or more, preferably 1.5% or more, especially 1.8% or more, from the viewpoint of making the boundary between the display portion and its surrounding members difficult to detect when the display device is turned off. More than 2.2% is preferred. On the other hand, the above-mentioned average haze needs to be 60% or less, preferably 45% or less, and more preferably 30% or less from the viewpoint of suppressing whitening of the screen of the display device when the display device is turned off. In particular, it is preferably 20% or less, and further preferably 12% or less.

In the colored adhesive layer 11 of the present embodiment, the difference (absolute value) between the haze value at a wavelength of 780 nm and the haze value at a wavelength of 380 nm (absolute value) is preferably 15% or less, especially 10% or less. More preferably, it is less than 7 percent. Thereby, when the colored adhesive layer 11 of the present embodiment is applied to a display device, when the display device is turned on, the color balance of the screen will not be changed regardless of the viewing position, angle, etc. As a result, when the display device is turned on, the visibility of images and images when viewed from a wide angle (wide-angle visibility) can be improved, and good image quality can be provided.

The lower limit of the difference in the above-mentioned haze value may be 0%, but from the viewpoint that the above-mentioned average haze can be easily adjusted to a desired value, 1% or more is preferable, and 2% or more is more preferable. Preferably, it is particularly preferably 3% or more, and further preferably 4% or more.

The haze value of the colored adhesive layer 11 in the present embodiment at a wavelength of 780 nm is easy to adjust the above-mentioned average haze, the difference of the haze value, and the standard deviation of the haze value to a desired value. In general, 0.1-50% is preferable, 0.5-30% is more preferable, 0.7-20% is especially preferable, and 1-10% is further preferable.

In addition, the haze value of the colored adhesive layer 11 of the present embodiment at a wavelength of 380 nm can be easily adjusted to a desired value from the average haze, the difference in the haze value, and the standard deviation of the haze value described later From the point of view, 0.1~60% is preferred, 1~40% is more preferred, especially 2~30% is preferred, 4~20% is further preferred, and 5~15% is most preferred.

In the colored adhesive layer 11 of this embodiment, the standard deviation of the haze value of each wavelength (ie, 380nm, 385nm, 390nm, ‧‧‧, 775nm, 780nm) at a 5nm pitch in the wavelength region of 380nm~780nm is 5 or less Preferably, it is particularly preferably 3 or less, and more preferably 2 or less. With this, when the colored adhesive layer 11 of the present embodiment is applied to a display device, when the display device is turned on, the color balance of the screen will not change regardless of the observation position, angle, etc. As a result, when the display device is turned on, the visibility of images and videos when viewed from a wide angle (wide-angle visibility) can be improved, and good image quality can be provided.

Although the lower limit of the aforementioned standard deviation is preferably 0, it is generally preferably 0.1 or more, particularly 0.4 or more, and more preferably 0.8 or more.

The total light haze value of the colored adhesive layer 11 of this embodiment is easy to adjust the above-mentioned average haze, the difference of the haze value, and the standard deviation of the haze value described later to a desired value. , 0.1~60% is preferred, 0.5~40% is more preferred, especially 1~30% is preferred, 1.5~20% is further preferred, and 2~15% is the most preferred.

In the present embodiment, the total light transmittance of the colored adhesive layer 11 (measured in accordance with JIS K7361-1:1997) is preferably 10% or more and less than 95%. The colored adhesive layer 11 is in accordance with CIE1976L* a*b* The chromaticity a* and chromaticity b* specified by the color system are preferably -7~7. In addition, the measuring method of chromaticity a* and chromaticity b* in this specification is as shown in the test example mentioned later.

By making the colored adhesive layer 11 satisfy the above-mentioned optical properties, when it is applied to a display device, a black tint is added when the display device is turned off, which can further improve the design of the display device (for example, the appearance of the display device when turned off) Coordination). Specifically, for display devices, especially in-vehicle display devices, it is possible to further enhance the sense of integrity with peripheral components, such as the sense of integrity with black frame materials. In addition, by setting the total light transmittance to 10% or more, it is possible to ensure good visibility as a display device (image and image visibility due to screen brightness).

The upper limit of the total light transmittance is preferably less than 95% from the viewpoint that it is easy to adjust the average haze, the difference of the haze value, and the standard deviation of the haze value described later to the desired value. , 90% or less is more preferable, especially 85% or less, and more preferably 80% or less. In addition, from the viewpoint of the visibility of the display device, the lower limit of the total light transmittance is preferably 25% or more, more preferably 40% or more, particularly preferably 50% or more, and further preferably 60%. Above% is better.

From the viewpoint of the design of the display device, the chromaticity a* is preferably -7~7, more preferably -5~5, particularly preferably -3~3, and further preferably -1~ 1 is better. In addition, the above-mentioned chromaticity b*, from the viewpoint of the design of the above-mentioned display device, is preferably -7~7, more preferably -5~5, particularly preferably -3~3, and further preferably- 1~1 is better.

On the other hand, the lightness L* specified by the CIE1976L*a*b* color system of the colored adhesive layer 11 is easy to adjust the average haze above 1%, which can make the boundary between the display device and the peripheral components difficult From a perceptible point of view, 99 or less is preferable, 95 or less is more preferable, especially 92 or less is preferable, and 91 or less is more preferable. In addition, the lightness L* is from the viewpoint of easily adjusting the average haze value to 60% or less to suppress whitening of the screen, or adjusting the difference and standard deviation of the haze value to a desired value, It is preferably 10 or more, more preferably 25 or more, particularly preferably 50 or more, further preferably 70 or more, and most preferably 80 or more.

The above optical properties can be achieved by appropriately selecting the type and content of the coloring agent constituting the adhesive of the coloring adhesive layer 11.

The lower limit of the average haze value of the average value of the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm of the liquid obtained by diluting the colorant 10,000 times with ethyl acetate is 1% or more More preferably, it is more preferably 2% or more, and more preferably 3% or more. In addition, for the above-mentioned coloring agent, the upper limit of the average haze is preferably 60% or less, preferably 40% or less, particularly preferably 30% or less, and further preferably 25% or less. By using such a coloring agent in an appropriate amount, it is easy to satisfy the average haze of the colored adhesive layer 11 described above.

In addition, the above-mentioned colorant, the difference between the haze value at a wavelength of 780nm and the haze value at a wavelength of 380nm of a liquid in which the colorant is diluted 10,000 times with ethyl acetate, preferably 30% or less, 25% The following is more preferable, especially 20% or less is preferable, and 16% or less is more preferable. By using such a coloring agent in an appropriate amount, it is easy to satisfy the difference in the haze value of the colored adhesive layer 11 described above.

Furthermore, although the lower limit of the difference in the above-mentioned haze value may be 0%, it is easy to adjust the average haze of the above-mentioned colored adhesive layer 11 to 1% or more, or it is easy to adjust the above-mentioned colored adhesive layer 11 From the viewpoint of adjusting the difference and standard deviation of the haze value to the desired value, it is preferably 0.1% or more, especially 0.5% or more, and further preferably 1% or more.

The haze value of the above-mentioned colorant diluted 10,000 times with ethyl acetate at a wavelength of 780nm is preferably 0.1-50%, more preferably 0.5-40%, especially 1-30%. Further preferably 2-25%. In addition, the haze value at the wavelength of 380nm of the liquid diluted 10,000 times with ethyl acetate is preferably 1~60%, more preferably 3~50%, especially 6~40%. Better, further preferably 10~30%. Thereby, it is easy to satisfy the above-mentioned average haze, the difference of the haze value, and the standard deviation of the haze value mentioned later.

Furthermore, the haze of the liquid diluted 10,000 times with ethyl acetate in the wavelength range of 380nm~780nm at 5nm pitch (ie 380nm, 385nm, 390nm, ‧‧‧, 775nm, 780nm) The standard deviation of the value is preferably 10 or less, more preferably 8 or less, particularly preferably 6 or less, and further preferably 5 or less. Although the lower limit of the above standard deviation is preferably 0, it is usually 0.1 or more, especially 0.2 or more, and further 0.3 or more. As a result, it is easy to satisfy the standard deviation of the haze value of the colored adhesive layer 11 described above.

The above-mentioned colorant may be a pigment or a dye. The pigment may 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 can be appropriately selected according to the color of the peripheral components that you want to show the overall feeling, but generally dark or strong colors such as black, coffee, dark blue, purple, and blue are preferred, and black is particularly preferred.

Examples of inorganic pigments include carbon black, cobalt pigments, iron pigments, chromium pigments, titanium pigments, vanadium pigments, zirconium pigments, molybdenum pigments, ruthenium pigments, platinum pigments, ITO (Indium tin oxide)-based dyes, ATO (antimony tin oxide)-based dyes, etc.

In addition, as organic pigments and organic dyes, for example, amine-based pigments, cyanine-based pigments, merocyanine-based pigments, croconium-based pigments, and squalium ) Pigments, azulenium pigments, polymethine pigments, naphthoquinone pigments, pyrylium pigments, phthalocyanine pigments, naphthalocyanine pigments, naphthalene Naphtholactam pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene pigments, dioxazine pigments, quinacrine Quinacridone dyes, isoindolinone dyes, quinophthalone dyes, pyrrole dyes, thioindigo dyes, metal complex dyes (metal complex salt dyes) ), dithiol metal complex dyes, indole phenol dyes, triallylmethane dyes, anthraquinone dyes, dioxazine dyes, naphthol dyes , Azomethine (azomethine) pigments, benzimidazolone (benzimidazolone) pigments, pyranthron (pyranthron) dyes and threne dyes, etc.

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

The above-mentioned pigments or dyes can be appropriately mixed and used in order to obtain target physical properties in the colored adhesive layer 11.

Among the above-mentioned colorants, carbon black, nigrosine-based black dyes, and chromate-based black dyes are preferred from the viewpoint of easily satisfying the above-mentioned physical properties and easily exhibiting a sense of integration with peripheral members. Furthermore, carbon black may be subjected to a predetermined treatment (for example, a solvophilization treatment) on its surface, or not.

The type of adhesive constituting the colored adhesive layer 11 of the colored adhesive sheet 1 of the present embodiment is not particularly limited, and may be, for example, acrylic adhesive, polyester adhesive, polyurethane adhesive, and rubber adhesive. , Silicone-based adhesives, etc. In addition, the adhesive may be any of a latex type, a solvent type, or a solvent-free type, and may be either a crosslinked type or a non-crosslinked type. Among them, acrylic adhesives with excellent adhesive properties and optical properties are preferred.

In addition, as an acrylic adhesive, it may be active energy ray curable or active energy ray non-curable. In addition, as an acrylic adhesive, a cross-linked type is preferred, and a thermal cross-linked type is further preferred.

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

The coloring agent (C) contained in the adhesive composition P is the above-mentioned coloring agent. The adhesive obtained from the adhesive composition P can exhibit excellent optical properties, adhesive force, durability (step followability under high temperature and high humidity conditions) and the like. In addition, in this specification, (meth)acrylic acid means both acrylic acid and methacrylic acid. Other similar terms are also the same. In addition, "polymer" also includes the concept of "copolymer".

(1) Ingredients of the adhesive composition (1-1) (Meth) acrylate polymer (A) In the (meth)acrylate polymer (A) of this embodiment, as a monomer unit constituting the polymer, a reactive group-containing monomer having a reactive group that reacts with the crosslinking agent (B) in the molecule is included Body is good. The reactive group derived from the reactive group-containing monomer reacts with the crosslinking agent (B) to form a crosslinked structure (three-dimensional network structure), and an adhesive having a desired cohesive force is obtained.

Examples of the above-mentioned reactive group-containing monomers include monomers having a hydroxyl group in the molecule (hydroxyl-containing monomers), monomers having a carboxyl group in the molecule (carboxyl group-containing monomers), and an amine group in the molecule. The monomers (amine-containing monomers) and so on. Among them, 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 is also preferred.

Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxypropyl (meth)acrylate. Hydroxyalkyl (meth)acrylates such as hydroxybutyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like. Among them, from the viewpoint of the reactivity of the hydroxyl group of the obtained (meth)acrylate polymer (A) with the crosslinking agent (B) and the copolymerizability with other monomers, it is assumed that it has a carbon number of 1 to The hydroxyalkyl (meth)acrylate of 4 hydroxyalkyl is preferred. Specifically, for example, 2-hydroxyethyl (meth)acrylate or 4-hydroxybutyl (meth)acrylate, etc. can be mentioned well, especially 2-hydroxyethyl acrylate or acrylic acid 4 can be mentioned well. -Hydroxybutyl ester. These can be used individually or in combination of 2 or more types.

Examples of the carboxyl group-containing monomer include 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 of the obtained (meth)acrylate polymer (A) with 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.

Examples of the amine group-containing monomer include aminoethyl (meth)acrylate, n-butylaminoethyl (meth)acrylate, and the like. These can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A), as the monomer unit constituting the polymer, the lower limit is preferably 1% by mass or more of reactive group-containing monomers, and more preferably 5% by mass or more. Preferably, it is particularly preferable to contain 10% by mass or more. In addition, from the tendency that the dispersibility of the colorant (C) in the adhesive becomes better, it is more preferable to contain 12% by mass or more, and 15% by mass or more is most preferable. On the other hand, the (meth)acrylate polymer (A), as the monomer unit constituting the polymer, preferably contains 35% by mass or less of reactive group-containing monomer as the upper limit, and preferably contains 30% by mass % Or less is more preferable, especially 20 mass% or less is preferable. In addition, in terms of the tendency that the dispersibility of the colorant (C) in the adhesive becomes better, the content of 18% by mass or less is more preferable. The (meth)acrylate polymer (A) contains a reactive group-containing monomer as a monomer unit in the above-mentioned amount, and the resulting adhesive can form a good crosslinked structure and can obtain a desired cohesive force. In addition, the dispersibility of the colorant (C) in the adhesive tends to become better, and the obtained adhesive has good reproducibility and uniformity of the above-mentioned optical physical properties, and exhibits excellent design and visibility. Furthermore, when the reactive group-containing monomer is a hydroxyl group-containing monomer, the content is particularly preferably 15% by mass or more. At this time, a predetermined amount of hydroxyl groups will remain in the adhesive. The hydroxyl group is a hydrophilic group, and such a hydrophilic group is present in the adhesive in a predetermined amount. Even when the adhesive is placed under high temperature and high humidity conditions, it will be the same as the moisture immersed in the adhesive under the high temperature and high humidity conditions. The solubility is good, and as a result, the whitening of the adhesive can be suppressed when returning to normal temperature and humidity (excellent heat and humid whitening resistance).

In addition, the (meth)acrylate polymer (A) preferably does 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 the carboxyl group-containing monomer, the adhesion target of the adhesive can be suppressed, and the occurrence of defects due to acid, such as tin-doped indium oxide (ITO), etc. transparent conductive film, metal film, etc. At that time, such defects (corrosion, resistance value change, etc.) occur due to acid. However, it is acceptable to contain a carboxyl group-containing monomer to such an extent that this defect does not occur. Specifically, in the (meth)acrylate polymer (A), as a monomer unit, a carboxyl group-containing monomer may be allowed to be contained in 0.1% by mass or less, preferably 0.01% by mass or less, more preferably 0.001% by mass %the following.

The (meth)acrylate polymer (A) preferably contains an alkyl (meth)acrylate as a monomer unit constituting the polymer. This can show good adhesion. The alkyl group may be linear or branched.

The alkyl (meth)acrylate has an alkyl (meth)acrylate having 1 to 20 carbon atoms in the alkyl group from the viewpoint of adhesion and dispersibility of the coloring agent (C). (Meth) acrylate alkyl esters having 1 to 20 carbon atoms in the alkyl group include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, (meth) ) N-butyl acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-hexyl (meth)acrylate Decyl ester, n-lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, etc. Among them, from the viewpoint of improving the adhesiveness, (meth)acrylates with alkyl carbon numbers of 1 to 8 are preferred, and methyl (meth)acrylate, n-butyl (meth)acrylate or ( 2-ethylhexyl meth)acrylate is particularly preferred, and methyl methacrylate, n-butyl acrylate, or 2-ethylhexyl acrylate is more preferred. In addition, these can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A) preferably contains 50% by mass or more of alkyl (meth)acrylate as the monomer unit constituting the polymer, particularly preferably 60% by mass or more, and further It is preferable to contain 65% by mass or more. If the lower limit of the content of the alkyl (meth)acrylate is the above, the (meth)acrylate polymer (A) can exhibit appropriate adhesiveness. In addition, the dispersibility of the colorant (C) in the adhesive tends to become better, and the (meth)acrylate polymer (A) does not impair the desired adhesiveness. Thereby, the obtained adhesive can exhibit suitable adhesiveness, and at the same time, the reproducibility and uniformity of the above-mentioned optical physical properties are good, and it shows excellent design and visibility. On the other hand, the (meth)acrylate polymer (A) preferably contains 99% by mass or less of alkyl (meth)acrylate as the monomer unit constituting the polymer, and preferably contains 95% by mass or less. More preferably, the content is particularly preferably 90% by mass or less, and more preferably 85% by mass or less. The upper limit of the content of the alkyl (meth)acrylate is as described above, and an appropriate amount of other monomer components such as a reactive functional group-containing monomer can be introduced into the (meth)acrylate polymer (A).

The (meth)acrylate polymer (A) may preferably contain a monomer having an alicyclic structure (alicyclic structure-containing monomer) in the molecule as a monomer unit constituting the polymer. Since the alicyclic structure-containing monomer has a large volume, by making it exist in the polymer, it can be estimated that the distance between the polymers can be enlarged, and the obtained adhesive can be made excellent in flexibility. This can make the adhesive's step followability excellent.

The carbocyclic ring of the alicyclic structure containing the alicyclic structure monomer may have a saturated structure or may have a partially unsaturated bond. In addition, the alicyclic structure may be a monocyclic alicyclic structure or a polycyclic alicyclic structure such as a bicyclic ring or a tricyclic ring. From the viewpoint of making the obtained (meth)acrylate polymer (A) have an appropriate distance from each other and imparting higher stress relaxation to the adhesive, the above-mentioned alicyclic structure is a polycyclic alicyclic structure (multiple Ring structure) is preferred. 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 viewpoint of imparting stress relaxation properties as described above, the number of carbons in the alicyclic structure (refers to the number of carbons in all parts forming the ring, and the total number of carbons when a plurality of rings exist independently) is usually 5 The above is preferable, and 7 or more is particularly preferable. 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.

As the aforementioned alicyclic structure-containing monomer, specifically, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, adamantyl (meth)acrylate, (meth)acrylic acid Isocampanate, dicyclopentenyl (meth)acrylate, dicyclopentenoxyethyl (meth)acrylate, etc., among them, dicyclopentyl (meth)acrylate which can exhibit better step followability Ester (the number of carbons in the alicyclic structure: 10), adamantyl (meth)acrylate (the number of carbons in the alicyclic structure: 10) or isocamyl (meth)acrylate (the number of carbons in the alicyclic structure: 7) Preferably, isocamyl (meth)acrylate is more preferable, and isobornyl acrylate is more preferable. These can be used individually by 1 type, and can also be used in combination of 2 or more types.

When the (meth)acrylate polymer (A) contains an alicyclic structure-containing monomer as the monomer unit constituting the polymer, it is preferable to contain 1% by mass or more of the alicyclic structure-containing monomer, especially The content is preferably 4% by mass or more, and more preferably 8% by mass or more. In addition, the (meth)acrylate polymer (A) preferably contains 30% by mass or less of an alicyclic structural monomer as the monomer unit constituting the polymer, and particularly preferably contains 22% by mass or less. It is more preferable to contain 14% by mass or less. By making the content of the alicyclic structure-containing monomer within the above range, the resulting adhesive can have better step-following properties and better adhesion to plastics.

In addition, the (meth)acrylate polymer (A) described above preferably contains a nitrogen atom-containing monomer as a monomer unit constituting the polymer. The presence of a nitrogen atom-containing monomer as a structural unit in the polymer can impart a predetermined polarity to the adhesive, and can have a certain degree of polarity to an adherend like glass, and has excellent affinity. From the viewpoint of allowing the (meth)acrylate polymer (A) to have appropriate rigidity, a monomer having a nitrogen-containing heterocyclic ring is preferably used as the nitrogen atom-containing monomer. In addition, from the viewpoint of increasing the degree of freedom from the nitrogen atom-containing monomer portion in the high-dimensional structure constituting the adhesive, the nitrogen atom-containing monomer can be used to form the (meth)acrylate polymer (A) In addition to one polymerizable group in the polymerization of ), it is preferable that the reactive unsaturated double bond bonding group is not contained.

As the monomer having a nitrogen-containing heterocyclic ring, for example, N-(meth)acryloyl morpholine, N-vinyl-2-pyrrolidone, and N-(meth)acryloyl Pyrrolidone, N-(meth)acryloylpiperidine, N-(meth)acryloylpyrrolidine, N-(meth)acryloylaziridine, aziridinylethyl (methyl) ) Acrylate, 2-vinylpyridine, 4-vinylpyridine, 2-vinylpyrazine (pyrazine), 1-vinylimidazole, N-vinylcarbazole, N-vinylphthalimide Etc., N-(meth)acrylic methrin, which can exert better adhesive force, is preferable, especially N-acrylic methrin. These can be used individually by 1 type, and can also be used in combination of 2 or more types.

When the (meth)acrylate polymer (A) contains a nitrogen atom-containing monomer as the monomer unit constituting the polymer, it is preferable to contain the nitrogen atom-containing monomer at 1% by mass or more, especially 4 mass% % Or more is preferable, and it is more preferable to contain 8 mass% or more. In addition, the (meth)acrylate polymer (A) preferably contains 20% by mass or less of the nitrogen atom-containing monomer as the monomer unit constituting the polymer, particularly preferably 16% by mass or less, and further The content is preferably 12% by mass or less. If the content of the nitrogen atom-containing monomer is within the above range, the resulting adhesive can fully exhibit excellent adhesion to glass.

The (meth)acrylate polymer (A) may contain other monomers as monomer units constituting the polymer as desired. As other monomers, it is preferable that the above-mentioned function of the reactive functional group-containing monomer is not hindered, and a monomer that does not contain a reactive functional group is preferable. Examples of the monomer include alkoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, and other alkoxyalkyl (meth)acrylates, vinyl acetate, and styrene. Wait. These can be used individually or in combination of 2 or more types.

The (meth)acrylate polymer (A) is preferably a linear polymer. By using a linear polymer, molecular chain entanglement is likely to occur, and the improvement of cohesive force can be expected, so it is easy to make the storage elastic modulus, gel fraction and adhesive force of the obtained adhesive suitable. It has excellent step followability 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. By using solution polymer, it is easy to obtain high molecular weight polymer, and the improvement of cohesive force can be expected, so it is easy to make the storage elastic modulus, gel fraction and adhesive force of the obtained adhesive become suitable, and it is high at high temperature. It has excellent step followability under wet conditions.

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

The weight average molecular weight of the (meth)acrylate polymer (A) is preferably 200,000 or more as the lower limit, especially 300,000 or more, and further preferably 400,000 or more. From the colorant (C) From the viewpoint of dispersibility, 500,000 or more is preferable, and 700,000 or more is particularly preferable. By setting the lower limit of the weight average molecular weight of the (meth)acrylate polymer (A) within the above range, it is easy to make the storage elastic modulus, gel fraction, and adhesive force of the resulting adhesive suitable. And under the conditions of high temperature and humidity, the followability of the step difference is excellent. In addition, since the dispersibility of the colorant (C) in the adhesive tends to be good, the resulting adhesive has good reproducibility and uniformity of the above-mentioned optical properties, and exhibits excellent design and visibility.

In addition, the upper limit of the weight average molecular weight of the (meth)acrylate polymer (A) is preferably 2 million or less, particularly preferably 1.5 million or less, and further preferably 1 million or less. By making the upper limit of the weight average molecular weight of the (meth)acrylate polymer (A) within the above-mentioned range, it is easy to make the storage elastic modulus, gel fraction, and adhesive force of the obtained adhesive suitable. However, the initial stage difference followability is better. In addition, the weight average molecular weight in this specification is a standard polystyrene conversion value measured by a gel permeation chromatography (GPC) method.

In the adhesive composition P, the (meth)acrylate polymer (A) may be used alone or in combination of two or more.

(1-2) Crosslinking agent (B) The crosslinking agent (B) crosslinks the (meth)acrylate polymer (A) by heating the adhesive composition P, thereby forming a good three-dimensional network structure. Thereby, the cohesive force of the obtained adhesive can be increased, and the step followability under high temperature and high humidity conditions is excellent.

As the above-mentioned crosslinking agent (B), any one that can react with the reactive group possessed by the (meth)acrylate polymer (A) may be used. For example, isocyanate-based crosslinking agents, epoxy-based crosslinking agents Linking agent, amine crosslinking agent, melamine crosslinking agent, aziridine crosslinking agent, amine crosslinking agent, aldehyde crosslinking agent, oxazoline crosslinking agent, metal alkoxy compound crosslinking agent Linking agents, metal chelate-based cross-linking agents, metal salt-based cross-linking agents, ammonium salt-based cross-linking 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, and the (meth)acrylate polymer ( A) When the reactive group possessed is a carboxyl group, it is better to use an epoxy-based crosslinking agent having excellent reactivity with the carboxyl group. In addition, the crosslinking agent (B) can be used individually by 1 type or in combination of 2 or more types.

The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. Examples of polyisocyanate compounds include aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene isocyanate; isocyanate; Alicyclic polyisocyanates such as phorone diisocyanate, hydrogenated diphenylmethane diisocyanate, etc., and these biuret, trimeric isocyanate, and further with ethylene glycol, propylene glycol, neopentyl glycol, three Addition products of reactants of low-molecular-weight active hydrogen-containing compounds such as methylolpropane and castor oil. Among them, from the viewpoint of reactivity with hydroxyl groups, aromatic polyisocyanates modified with trimethylolpropane are preferred, toluene diisocyanate modified with trimethylolpropane and xylene diisocyanate modified with trimethylolpropane Base diisocyanate is particularly preferred.

Examples of epoxy-based crosslinking agents include 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N′,N′-tetraglycidyl M-xylene diamine, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, diglycidyl ether Base amine and so on. Among them, from the viewpoint of reactivity with a carboxyl group, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane is preferred.

For the content of the crosslinking agent (B) in the adhesive composition P, with respect to 100 parts by mass of the (meth)acrylate polymer (A), the lower limit is preferably 0.01 parts by mass or more, especially 0.05 parts by mass The above is preferable, and more preferably 0.1 part by mass or more. In addition, the content is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, particularly preferably 1 part by mass or less, and further preferably 0.4 parts by mass or less. By setting the content of the crosslinking agent (B) in the above range, the resulting adhesive exerts good cohesive force, and easily meets the desired storage elastic modulus, gel fraction and adhesive force, etc., under high temperature and high humidity conditions The level difference is good to follow.

(1-3) Coloring agent (C) The colorant (C) is the above-mentioned colorant. The specific types are as described above.

The content of the colorant (C) to 100 parts by mass of the (meth)acrylate polymer (A) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and particularly preferably 0.1 parts by mass or more, More preferably, it is 0.2 parts by mass or more. In addition, the aforementioned content is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, particularly preferably 2 parts by mass or less, and further preferably 1 part by mass or less. By setting the content of the coloring agent (C) in the above range, it is easy to satisfy the above optical properties.

(1-4) Active energy ray hardening component (D) In the adhesive formed by cross-linking the adhesive composition P, the active energy ray hardening component (D) is presumably polymerized with the active energy ray hardening component (D) and The crosslinked structure (three-dimensional mesh structure) of the (meth)acrylate polymer (A) is entangled. The adhesive with this high-dimensional structure exhibits very excellent durability, and has excellent step followability under high temperature and high humidity conditions.

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

Multifunctional acrylate monomers, for example, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth) Acrylate, polyethylene glycol di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, hydroxytrimethyl acetate neopentyl glycol di(meth)acrylate, dicyclopentane Di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, caprolactone modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified di(meth) phosphate Base) acrylate, bis(acryloxyethyl) trimer isocyanate, allylated cyclohexyl di(meth)acrylate, ethoxylated bisphenol A diacrylate, 9,9-bis[4 -(2-propenyloxyethoxy)phenyl] pyridine and other bifunctional types; 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, tris(acrylic acid) Ethylethyl) trimeric isocyanate, ε-caprolactone modified tris (2-(meth)acryloyloxyethyl) trimeric isocyanate and other trifunctional types; diglycerol tetra(meth)acrylate, new 4-functional type such as pentaerythritol tetra(meth)acrylate; 5-functional type such as dineopentaerythritol penta(meth)acrylate modified by propionic acid; dineopentaerythritol hexa(meth)acrylate , Caprolactone is used to modify the 6-functional type of dineopentaerythritol hexa(meth)acrylate, etc. These can be used individually by 1 type, and can also be used in combination of 2 or more types. From the viewpoint of compatibility with the (meth)acrylate polymer (A), the polyfunctional acrylate monomer preferably has a molecular weight of less than 1,000.

Among the above, from the viewpoint of the foaming resistance of the resulting adhesive, di(acryloxyethyl) trimer isocyanate, tris(acryloxy ethyl) trimer isocyanate, and ε-caprolactone Modified tris (2-(meth)acryloyloxyethyl) trimer isocyanate and other multifunctional acrylate monomers containing trimer isocyanate structure in the molecule, or tricyclodecane dimethanol (meth)acrylic acid A polyfunctional acrylate monomer having a cyclic structure (especially a cycloalkane structure) in the molecule, such as an ester, is preferably a multifunctional acrylate monomer having trifunctional or higher and a trimeric isocyanate structure in the molecule, or It is more preferable to use a polyfunctional acrylate-based monomer having two or more functions and a polycyclic structure (especially a cycloalkane polycyclic structure) in the molecule, and ε-caprolactone is used to modify tris(2-(methyl) Acrylic oxyethyl) trimeric isocyanate or tricyclodecane dimethanol (meth) acrylate is particularly preferred, and ε-caprolactone is further used to modify tris(2-propylene oxyethyl) trimeric isocyanate Or tricyclodecane dimethanol acrylate is better, and ε-caprolactone is used to modify tris(2-propenyloxyethyl) trimeric isocyanate.

The content of the active energy ray curable component (D) in the adhesive composition P, from the viewpoint that the adhesive after curing the active energy ray has more excellent step followability under high temperature and high humidity conditions, it is suitable for (A The lower limit of 100 parts by mass of the base) acrylate polymer (A) is preferably 1 part by mass or more, particularly preferably 3 parts by mass or more, and more preferably 4 parts by mass or more. On the other hand, the above content, from the viewpoint of the adhesive force of the adhesive after curing by active energy rays, the upper limit is preferably 20 parts by mass or less, particularly preferably 12 parts by mass or less, and 8 parts by mass or less For better.

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

As such a photopolymerization initiator (E), for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminobenzene Ethanone, 2,2-Dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenyl Propan-1-one, 1-hydroxycyclohexylphenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl-propan-1-one, 4-( 2-Hydroxyethoxy) phenyl-2-(hydroxy-2-propyl) ketone, diphenyl ketone, p-phenyl diphenyl ketone, 4,4-diethylamino diphenyl ketone, two Chlorodiphenyl ketone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methyl thioxanthone (2-methyl thioxanthone), 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl Ketal, p-dimethylaminobenzoate, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]acetone], 2,4,6- Trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzyl)phenylphosphine oxide, etc. These can be used individually or in combination of 2 or more types.

Among the above, when irradiated with ultraviolet rays through a plastic plate containing an ultraviolet absorber, a phosphine oxide-based photopolymerization initiator that is easy to be broken and is easy to harden the adhesive is preferred. Specifically, 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzyl)phenylphosphine oxide, etc. are preferable.

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

The mass ratio of the amount of the photopolymerization initiator (E) to the amount of the colorant (C) (photopolymerization initiator (E)/colorant (C)) is preferably 0.01 or more, especially 0.1 or more Better, more preferably 0.2 or more. In addition, the mass ratio is preferably 5 or less, particularly 3 or less, and more preferably 1 or less. By setting the ratio of the amount of the photopolymerization initiator (E) to the amount of the coloring agent (D) in the above range, the above optical properties can be satisfied, and at the same time, it is easy to obtain a suitable cohesive force or adhesiveness by curing with active energy rays Adhesives, and the followability of the step under the conditions of high temperature and humidity is easy to become better.

(1-6) Various additives Adhesive composition P can be added with various additives commonly used in acrylic adhesives as desired, such as silane coupling agents, rust inhibitors, ultraviolet absorbers, antistatic agents, adhesion imparting agents, antioxidants, light stabilizers, and softening agents. Agents, refractive index modifiers, etc. In addition, the polymerization solvent and the dilution solvent mentioned later are not included in the additive which comprises the adhesive composition P.

Among the above, the adhesive composition P preferably contains a silane coupling agent. As a result, even if the adherend is a plastic plate or even a glass member, the adhesion to the adherend can be improved, and the step followability under high temperature and high humidity conditions is better.

As the silane coupling agent, an organosilicon compound having at least one alkoxysilyl group in the molecule, which has good compatibility with the (meth)acrylate polymer (A) and light penetration is preferred .

As the silane coupling agent, for example, vinyl trimethoxy silane, vinyl triethoxy silane, methacryloxy propyl trimethoxy silane and other polymerizable unsaturated group-containing silicon compounds, 3 -Glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and other silicon compounds having epoxy structure, 3-mercaptopropyltrimethoxysilane, Mercapto-containing silicon compounds such as 3-mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl )-3-Aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane and other amino-containing silicon compounds, 3-chloropropyl Trimethoxysilane, 3-isocyanatopropyltriethoxysilane, or at least one of these, with methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, ethyl Condensates of alkyl-containing silicon compounds such as trimethoxysilane. These can be used individually by 1 type, and can also be used in combination of 2 or more types.

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

(2) Preparation of adhesive composition The adhesive composition P can be produced by producing a (meth)acrylate polymer (A), and the resulting (meth)acrylate polymer (A) can be combined with a crosslinking agent (B) and a coloring agent ( C) It is produced by adding active energy ray curable component (D), photopolymerization initiator (E), additives, etc. as desired while mixing.

The (meth)acrylate polymer (A) can be produced by polymerizing a mixture of monomers constituting the polymer by a normal radical polymerization method. The polymerization of the (meth)acrylate polymer (A) can be carried out by a solution polymerization method using a polymerization initiator as desired. However, the present invention is not limited to this, and solventless polymerization is also possible. Examples of the polymerization solvent include ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone, etc., and two or more of them are also used in combination.

Examples of the polymerization initiator include azo compounds, organic peroxides, and the like, and two or more types may be used in combination. 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-methylpropionate), 4,4′-azobis(4-cyanovaleric acid) (4,4′-azobis(4-cyanovaleric acid )), 2,2'-azobis(2-hydroxymethylpropionitrile), 2,2'-azobis[2-(2-imidazolin-2-yl)propane], etc.

Examples of organic peroxides include benzyl peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, and di-n-propyl peroxydicarbonate. , Peroxydicarbonate bis(2-ethoxyethyl), t-butyl peroxyneodecanoate, t-butyl peroxyisobutyrate, (3,5,5-trimethylhexyl) Peroxide, dipropylene peroxide, diacetyl peroxide, etc.

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

To obtain the (meth)acrylate polymer (A), to the solution of the (meth)acrylate polymer (A), add a crosslinking agent (B), a colorant (C), and a diluting solvent as desired , Active 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. Furthermore, when any of the above-mentioned components is used in a solid state, or when precipitation occurs when mixed with other components in an undiluted state, the component may be separately dissolved or diluted with a diluting solvent in advance. Mix with other ingredients.

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 methylene chloride and vinyl chloride, methanol, ethanol, and propanol Alcohols such as, butanol, 1-methoxy-2-propanol, ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, cyclohexanone, etc., esters such as ethyl acetate and butyl acetate, Serosu series solvents such as ethyl Serosu.

The concentration and viscosity of the coating solution prepared in this manner are not particularly limited as long as they are in the coatable range, and can be appropriately selected according to the situation. For example, the adhesive composition P is diluted to a concentration of 10 to 60% by mass. In addition, when obtaining a coating solution, the addition of a dilution solvent etc. is not an essential condition, as long as the adhesive composition P has the viscosity which can apply|coat, the dilution solvent may not be added. At this time, the adhesive composition P becomes a coating solution in which the polymerization solvent of the (meth)acrylate polymer (A) is directly used as the dilution solvent.

(3) Formation of colored adhesive layer The colored adhesive layer 11 of this embodiment is preferably composed of an adhesive crosslinked by 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 used as a drying treatment at the time of volatilizing a dilution solvent or the like from the coating layer of the adhesive composition P applied to the desired object.

The heating temperature of the heat treatment is preferably 50~150℃, especially 70~120℃. In addition, the heating time is preferably 10 seconds to 10 minutes, especially 50 seconds to 2 minutes.

After the heat treatment, if necessary, an aging period of about 1 to 2 weeks at room temperature (for example, 23° C., 50% RH) can also be set. When the aging period is required, after the aging period has passed, and when the aging period is not required, the adhesive is formed after the heat treatment is completed.

By the above-mentioned heat treatment (and aging), the (meth)acrylate polymer (A) is sufficiently crosslinked via the crosslinking agent (B). The adhesive obtained in this way easily meets the desired storage elastic modulus, gel fraction and adhesive force, etc., and has excellent step followability under high temperature and high humidity conditions.

(4) Physical properties of adhesive The adhesive of this embodiment preferably has the following physical properties. (4-1) Gel fraction The gel fraction of the adhesive of this embodiment is preferably 20% or more as the lower limit, more preferably 40% or more, particularly preferably 50% or more, and further preferably 60% or more. When the lower limit of the gel fraction of the adhesive is the above, the cohesive force of the adhesive becomes higher, and the step followability under high temperature and high humidity conditions is better. In addition, as for the gel fraction of the adhesive of the present embodiment, the upper limit is preferably 100% or less, more preferably 90% or less, particularly preferably 80% or less, and more preferably 70% or less. The upper limit of the gel fraction of the adhesive is as described above, so that the adhesive does not harden excessively, and is excellent in the initial step followability and the step followability under high temperature and high humidity conditions. In addition, good adhesion can be displayed, and the adhesion to the adherend is better.

Here, the method of measuring the gel fraction of the adhesive is as shown in the test example described later. In addition, in the case of an active energy ray-curable adhesive, it is set as the gel fraction of the adhesive after the active energy ray has been cured. Furthermore, in the case of an active energy ray-curable adhesive, the gel fraction of the adhesive before curing of the active energy ray is preferably 20 to 70% from the viewpoint of good initial step followability. 30~60% is particularly preferred, and 40~55% is more preferred.

(4-2) Storage elastic modulus Regarding the storage elastic modulus of the adhesive of this embodiment at 23°C, as the lower limit, it is preferably 0.001 MPa or more, more preferably 0.01 MPa or more, especially 0.05 MPa or more, and further 0.1 MPa or more Better. By setting the lower limit of the storage elastic modulus to the above, the step followability under high temperature and high humidity conditions is excellent. In addition, the upper limit of the storage elastic modulus is preferably 2 MPa or less, more preferably 1 MPa or less, especially 0.8 MPa or less, further preferably 0.4 MPa or less, and most preferably 0.2 MPa or less. By setting the upper limit of the storage elastic modulus within the above range, the initial step followability and the step followability under high temperature and high humidity conditions are excellent.

Here, the storage modulus of elasticity in this specification is a value measured by the torsional shear method in compliance with JIS K7244-6 with a measurement frequency of 1 Hz. Specifically, it is as shown in the test example mentioned later. In addition, in the case of an active energy ray-curable adhesive, it is set as the storage elastic modulus of the adhesive after the active energy ray has been cured. Furthermore, in the case of an active energy ray curable adhesive, the storage elastic modulus of the adhesive before curing of the active energy ray is preferably 0.01 to 1 MPa from the viewpoint that the initial step followability is good. 0.02~0.5MPa is particularly preferred, and 0.04~0.1MPa is more preferred.

(5) The thickness of the colored adhesive layer The lower limit of the thickness of the colored adhesive layer 11 is preferably 1 μm or more, more preferably 2 μm or more, and particularly preferably 4 μm or more. By setting the lower limit of the thickness of the colored adhesive layer 11 within the above range, it is easy to satisfy the above-mentioned optical properties in relation to the content of the coloring agent (C), and at the same time, 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 10 μm or more, more preferably 20 μm or more, particularly preferably 50 μm or more, and more preferably 80 μm or more.

On the other hand, the upper limit of the thickness of the colored adhesive layer 11 is preferably 500 μm or less, more preferably 300 μm or less, especially 200 μm or less, and further preferably 150 μm or less. When the upper limit of the thickness of the colored adhesive layer 11 is within the above-mentioned range, the workability is good, and furthermore, the appearance defect due to the pressing trace is less likely to occur. Furthermore, in relation to the content of the coloring agent (C), it is easy to satisfy the aforementioned optical properties. In addition, the colored adhesive layer 11 can be formed in a single layer, or may be formed by stacking a plurality of layers.

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

As the release sheets 12a, 12b, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyparaphenylene film can be used. Ethylene dicarboxylate film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate film, ionomer resin film, ethylene‧(methyl ) Acrylic copolymer film, ethylene‧(meth)acrylate copolymer film, polystyrene film, polycarbonate film, polyimide film, fluorinated resin film, etc. In addition, such crosslinked films can be used. Furthermore, these laminated films may also be used.

The peeling surface of the peeling sheet 12a, 12b (especially the surface connected to the colored adhesive layer 11) is preferably subjected to a peeling treatment. Examples of the release agent used in the release treatment include alkyd, silicone, fluorine, unsaturated polyester, polyolefin, and wax release agents. In addition, among the release sheets 12a and 12b, one of the release sheets is preferably a heavy release type with a large release force, and the other release sheet is a light release type with a small release force.

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

2. Physical properties (adhesion) Regarding the adhesion of the colored adhesive sheet 1 of this embodiment to soda lime glass, as the lower limit, 1N/25mm or more is preferable, 2N/25mm or more is more preferable, 4N/25mm or more is particularly preferable, and 8N/ More preferably, it is 25 mm or more. If the lower limit of the adhesive force is within the above range, the step followability under high temperature and high humidity conditions is better. In addition, regarding the adhesive force of the colored adhesive sheet 1 of this embodiment to the soda lime glass, as the upper limit, 80N/25mm or less is preferred, 50N/25mm or less is more preferred, and 30N/25mm or less is particularly preferred . If the upper limit of the adhesive force is within the above range, good reworkability can be obtained, and when a bonding error occurs, the display device component can be reused, especially the expensive display device component.

Here, the adhesive force in this specification basically refers to the adhesive force measured in compliance with the 180∘ peeling method of JIS Z0237:2009, but the measured sample is 25mm wide and 100mm long, and the measured sample is pasted on the adherend , After pressurizing at 0.5MPa, 50℃ for 20 minutes, after leaving it under normal pressure, 23℃, 50%RH conditions for 24 hours, measuring at a peeling speed of 300mm/min. In addition, in the case of an active energy ray-curable adhesive, it is about the adhesive force of the colored adhesive layer hardened by the active energy ray after being adhered to the adherend. Furthermore, in the case of an active energy ray-curable adhesive, the adhesive force of the adhesive before curing of the active energy ray is 1 to 80 N from the viewpoint of adhesion to the adherend and reworkability /25mm is better, 2~50N/25mm is particularly preferred, and 4~30N/25mm is better.

3. Manufacturing of colored adhesive sheets As an example of the production of the colored adhesive sheet 1, the peeling surface of one peeling sheet 12a (or 12b) is coated with the coating liquid of the adhesive composition P, and the adhesive composition P is thermally crosslinked by heat treatment. After the coating layer is formed, the release surface of the release sheet 12b (or 12a) on the other side is laminated with the coating. When the aging period is required, the aging period is given, and the aging period is not required, and the coating layer directly becomes the colored adhesive layer 11. Thus, the colored adhesive sheet 1 can be obtained. The conditions for heat treatment and maturation are as described above.

As another example of the production of the colored adhesive sheet 1, the release surface of one release sheet 12a is coated with the above-mentioned coating liquid of the adhesive composition P, and the adhesive composition P is thermally crosslinked to form a coating. The cloth layer, the release sheet 12a with the coating layer was obtained. In addition, on the release surface of the other release sheet 12b, the coating liquid of the adhesive composition P is applied, and the adhesive composition P is thermally crosslinked by a heat treatment to form a coating layer to obtain a coating layer的release sheet 12b. Then, the peeling sheet 12a with a coating layer and the peeling sheet 12b with a coating layer are adhered so that the two coating layers are in contact with each other. Here, a plurality of release sheets with coating layers may be produced, and the coating layers may be pasted only in a desired number. When the aging period is required, the aging period is given, and the aging period is not required, and the coating layer directly becomes the colored adhesive layer 11. Thus, the colored adhesive sheet 1 can be obtained. According to this manufacturing example, even when the colored adhesive layer 11 is thick, it can be manufactured stably.

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

[display screen] The types of display devices (displays) related to this embodiment include, for example, automobile dashboards, car navigation systems, various meters installed in consoles, and other vehicle-mounted display devices, and general user-use tablet terminals. Display devices, display devices such as commercial tablet terminals or digital signage, and display devices such as outdoor digital signage. Such display devices are sometimes required to have an appearance coordination with peripheral components, or a sense of luxury. However, the display device of the present invention should not be limited to these.

As shown in FIG. 2, regarding the display device 2 of this embodiment, the structure includes: a first display device constituent member 21 (a display device constituent member); a second display device constituent member 22 (other display device constituent members); And the colored adhesive layer 11, which is located between these, adheres the first display device constituent member 21 and the second display device constituent member 22 to each other.

At least one of the first display device constituent member 21 and the second display device constituent member 22 may have a step at least on the surface to be adhered by the colored adhesive layer 11. In the present embodiment shown in FIG. 2, the first display device constituent member 21 has a level difference of the printed layer 3 and the like on the surface on the side of the colored adhesive layer 11.

The colored adhesive layer 11 of the above-mentioned display device 2 is the colored adhesive layer 11 of the above-mentioned colored adhesive sheet 1.

As the display device 2, for example, a liquid crystal (LCD) display, a light emitting diode (LED) display, an organic electroluminescence (organic EL) display, an electronic paper, etc. may be mentioned, and it may be a touch panel.

The first display device constituent member 21 is preferably a protective plate composed of a laminate containing such a glass plate, a plastic plate, and the like. At this time, the printing layer 3 is generally formed in a frame shape on the side of the colored adhesive layer 11 of the first display device constituent member 21.

The glass plate is not particularly limited, and examples include chemically strengthened glass, alkali-free glass, quartz glass, soda lime glass, barium-strontium-containing glass, aluminosilicate glass, lead glass, borosilicate glass, barium Borosilicate glass, etc. 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 plastic plate is not particularly limited, and examples include acrylic plates and polycarbonate plates. The thickness of the plastic plate is not particularly limited, and is usually 0.2 to 5 mm, preferably 0.4 to 3 mm.

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

The second display device constituent member 22 should be attached to the optical member and display module (for example, liquid crystal (LCD) module, light emitting diode (LED) module, organic electric An electroluminescence (organic EL) module, etc.), an optical member as a part of the display module, or a laminate including the display module is preferable.

Examples of the above-mentioned optical members include anti-scattering films, polarizers (polarizing films), polarizers, retardation films (retardation films), viewing angle compensation films, brightness enhancement films, contrast enhancement films, and liquid crystal polymer films , Diffusion film, transflective film, transparent conductive film, etc. As the anti-scattering film, a hard coat film formed by forming a hard coat layer on one side of a base film, etc. can be exemplified.

The material constituting the printed layer 3 is not particularly limited, and conventional materials for printing can be used. The thickness of the printed layer 3, that is, the lower limit of the height of the step, is preferably 3 μm or more, more preferably 5 μm or more, particularly preferably 7 μm or more, and most preferably 10 μm or more. By setting the lower limit value to be above the above, it is possible to sufficiently ensure the concealment of the circuit arrangement and the like from the side of the viewer. In addition, the upper limit is preferably 50 μm or less, more preferably 35 μm or less, particularly preferably 25 μm or less, and further preferably 20 μm or less. By setting the upper limit to the above-mentioned or less, it is possible to prevent deterioration of the step followability of the colored adhesive layer 11 to the printed layer 3.

As an example of manufacturing the display device 2 described above, the peeling sheet 12a on one side of the colored adhesive sheet 1 is peeled off, and the exposed colored adhesive layer 11 of the colored adhesive sheet 1 is printed with the presence of the first display device constituent member 21 The surface of the layer 3 side is pasted.

After that, from the colored adhesive layer 11 of the colored adhesive sheet 1, the other release sheet 12 b is peeled off, and the exposed colored adhesive layer 11 of the colored adhesive sheet 1 and the second display device constituent member 22 are bonded. In addition, as another example, the bonding order of the first display device constituent member 21 and the second display device constituent member 22 may be alternated.

When the colored adhesive layer 11 is curable with active energy rays, the first display device constituent member 21 and the second display device constituent member 22 are bonded via the colored adhesive layer 11 as described above, and then the colored adhesive layer 11 is irradiated. Energy line. Thereby, the energy ray curable component (D) in the colored adhesive layer 11 is polymerized, and the colored adhesive layer 11 is hardened. The energy ray irradiation to the colored adhesive layer 11 is usually carried out via either the first display device constituent member 21 or the second display device constituent member 22, preferably the first display device constituent member which is a protective panel. 21 to proceed.

The term "active energy ray" means that there are energy ions in electromagnetic waves or charged particle rays, and specific examples include ultraviolet rays, electron beams, and the like. Among the active energy rays, ultraviolet rays that are easy to operate are particularly preferred.

Ultraviolet rays can be irradiated by high-pressure mercury lamps, Fusion H lamps, xenon lamps, etc. The amount of ultraviolet radiation is preferably 50~1000mW/cm ² and 100~500mW/cm ² . Further, the light amount to 50 ~ 10000mJ / cm ² preferably, to 200 ~ 7000mJ / cm ² is more preferably to 500 ~ 3000mJ / cm ² is particularly preferred. On the other hand, the irradiation of electron beams can be carried out by an electron beam accelerator, etc. The irradiation dose of electron beams is preferably about 10 to 1000 krad.

As shown in FIG. 3, regarding the display device 2 of this embodiment, it is preferable to have a frame material 4 at the peripheral edge of the display device 2. The frame material 4 is preferably black. In addition, as the color tone of the frame material 4, the preferable range of lightness L*, chromaticity a*, and chromaticity b* specified in the CIE1976L*a*b* color system is used as a peripheral member as described earlier Tones. The frame material 4, by having this hue, is easily recognized by the human eye as a frame material with high-quality visually. In addition, in the colored adhesive layer 11 of this embodiment, since the frame material 4 has the above-mentioned color tone, the overall feeling with the frame material 4 is increased, and the appearance coordination is better.

In the display device 2, the physical properties of the colored adhesive layer 11 suppress whitening when the display device is turned off, thereby improving the design. Thereby, for example, a sense of integration with the black frame material 4 is imparted, and excellent appearance coordination is achieved. In addition, the above-mentioned display device 2 ensures visibility as a display device.

Furthermore, in the above-mentioned display device 2, when the colored adhesive layer 11 is formed of the adhesive composition P, since the colored adhesive layer 11 has excellent step followability under high temperature and high humidity conditions, even if the display device 2 is When placed in, for example, high temperature and high humidity conditions (for example, 85°C, 85%RH), it can also prevent floating and peeling near the step.

The above-mentioned level difference followability can be judged using the level difference follow-up rate (%) as an indicator. For the colored adhesive layer 11, the step following rate (%) shown in the following formula is used as the lower limit, preferably 10% or more, more preferably 20% or more, especially 40% or more, and further More than 60% is better. In addition, the upper limit of the step following rate is not particularly limited. Generally, it is preferably 80% or less, and particularly preferably 70% or less. Level difference follow-up rate (%)={(After a predetermined endurance test, the level difference height (μm) to maintain the state of being buried without bubbles, floating, peeling, etc.)/(the thickness of the colored adhesive layer)}×100 In addition, the test method of the step following rate is as shown in the test example described later.

The embodiments described above are described for easy understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above-mentioned embodiment includes all design changes or equivalents belonging to the technical scope of the present invention.

For example, one or both of the release sheets 12a and 12b of the colored adhesive sheet 1 may be omitted, and a desired optical member may be laminated instead of the release sheets 12a and/or 12b. In addition, the first display device constituent member 21 may have no step. In addition, not only the first display device constituent member 21 but the second display device constituent member 22 may have a step on the side of the colored adhesive layer 11. [Example]

Hereinafter, the present invention will be explained more specifically with examples and the like, but the scope of the present invention is not limited to these examples and the like.

[Example 1] 1. Preparation of (meth)acrylate polymer Copolymerize 70 parts by mass of 2-ethylhexyl acrylate, 15 parts by mass of methyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate by solution polymerization to prepare (meth)acrylate polymerization物(A). The molecular weight of the (meth)acrylate polymer (A) was measured by the method described later, and as a result, the weight average molecular weight (Mw) was 800,000.

2. Preparation of adhesive composition Change 100 parts by mass (based on solid content conversion value; the same below), using the (meth)acrylate polymer (A) obtained in step 1 above and 0.2 parts by mass of trimethylolpropane as the crosslinking agent (B) Toluene diisocyanate (manufactured by TOYO CHEM, product name "BHS8515"), 0.4 parts by mass of carbon black-based black pigment (C1) as the colorant (C), and 0.2 parts by mass of 3-glycidyl ether as the silane coupling agent The oxypropyltrimethoxysilane is mixed, fully stirred, and diluted with methyl ethyl ketone to obtain a coating solution of the adhesive composition.

Here, each blending amount (solid content conversion value) of the 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 abbreviations described in Table 1 are as follows. [(Meth)acrylate polymer (A)] 2EHA: 2-ethylhexyl acrylate MMA: methyl methacrylate HEA: 2-hydroxyethyl acrylate IBXA: Isobornyl acrylate ACMO: N-Acrylic Folin BA: n-butyl acrylate AA: Acrylic [Colorant (C)] C1~C6: Carbon black black pigments with physical properties shown in Table 2

3. Manufacturing of colored adhesive sheets The coating solution of the adhesive composition obtained in the above step 2 is applied with a knife coater, and one side of the polyethylene terephthalate film is peeled off with a silicone-based release agent. After the peeling treatment surface of the sheet (manufactured by LINTEC, product name "SP-PET752150"), a coating layer (thickness: 50 μm) was formed by heat treatment at 90°C for 1 minute. In addition, the coating solution of the adhesive composition obtained in the above step 2 was applied with a knife coater, and one side of the polyethylene terephthalate film was peeled off with a silicone-based release agent. After the peeling treatment surface of the lightly peelable peeling sheet (manufactured by LINTEC, product name "SP-PET381130"), a coating layer (thickness: 50 μm) was formed by heat treatment at 90°C for 1 minute.

Next, the above-obtained heavy release release sheet with a coating layer and the light release release sheet with a coating layer obtained above are pasted with the two coating layers in contact with each other, at 23°C, 50%RH It was aged for 7 days under the conditions of, and a colored adhesive sheet composed of a heavy peeling type release sheet/colored adhesive layer (thickness: 100 μm)/light peeling type peeling sheet was produced.

In addition, the thickness of the said adhesive layer is the value measured using the constant pressure thickness measuring device (The product name "PG-02" made by TECLOCK) in compliance with JIS K7130.

[Examples 2 to 8, Comparative Examples 1 to 2] The type and ratio of each monomer constituting the (meth)acrylate polymer (A), the weight average molecular weight (Mw) of the (meth)acrylate polymer (A), the type and blending of the colorant (C) Except that the amount, the blending amount of the silane coupling agent, and the thickness of the colored adhesive layer were changed to those shown in Table 1, the colored adhesive sheet was produced in the same manner as in Example 1. However, in Example 5, 5.0 parts by mass of ε-caprolactone was further added as the active energy ray curable component (D) to modify tris(2-propenoxyethyl) triisocyanate (manufactured by Shinnakamura Chemical Co., Ltd., Product name "NK ESTER A-9300-CL") and 0.5 parts by mass of 2,4,6-trimethylbenzyldiphenylphosphine oxide as a photopolymerization initiator (E) to obtain active energy ray hardening Sexual adhesive. In Comparative Example 1, although the coloring agent (C) was not used, the terms colored adhesive layer and colored adhesive sheet were used expediently.

In addition, the colored adhesive sheets of Examples 3 to 8 and Comparative Examples 1 to 2 were manufactured as follows. The coating solution of the adhesive composition prepared in the same manner as in Example 1 was applied with a knife coater, and one side of the polyethylene terephthalate film was peeled off with a silicone-based release agent After the peeling treatment surface of the heavy peeling type peeling sheet (manufactured by LINTEC, product name "SP-PET752150"), the coating layer was formed by heat treatment at 90°C for 1 minute. A light-peelable release sheet in which the coated layer side surface of the obtained heavy-peelable release sheet with a coating layer and one side of the polyethylene terephthalate film are peeled off with a silicone-based release agent (Product name "SP-PET381130" made by LINTEC) is bonded on the peel-off treated surface and cured at 23°C and 50%RH for 7 days to produce a heavy peeling type peeling sheet/coloring adhesive layer/light peeling type peeling Colored adhesive sheet

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): made by TOSOH TSK guard column HXL-H TSK ge1 GMHXL (×2) TSK ge1 G2000HXL ‧Measuring solvent: Tetrahydrofuran ‧Measuring temperature: 40℃

[Test Example 1] (Measurement of Haze Value of Colorant Diluent) Dilute C1~C6 colorants with ethyl acetate 10,000 times as a liquid, comply with JIS K7136:2000, and measure the haze using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd., product name "SH-7000", optical path length 10mm) 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; in the wavelength region The standard deviation of the haze value of each wavelength at a 5nm pitch from 380nm to 780nm. The respective results are shown in Table 2.

[Test Example 2] (Measurement of Gel Fraction) The colored adhesive sheets obtained in the examples and comparative examples were cut into a size of 80mm×80mm, the adhesive layer was placed on a polyester mesh (mesh size 200), and the mass was weighed with a precision balance, and the net alone was deducted Calculate the quality of only the adhesive. The mass at this time is M1.

Next, the adhesive attached to the above-mentioned polyester mesh was immersed in ethyl acetate at room temperature (23°C) for 24 hours. 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 further dried in an oven at 80°C for 12 hours. After drying, weigh the mass with a precision balance and deduct the mass of the net alone to calculate the mass of only the adhesive. The mass at this time is M2. The gel fraction (%) is expressed as (M2/M1)×100. The results are shown in Table 3.

Furthermore, regarding the colored adhesive sheet of Example 5, a plastic sheet (Mitsubishi Gas Chemical Co., Ltd.) is laminated on a polycarbonate resin (PC) sheet and a layer of methyl methacrylate resin (PMMA) on a lightly peelable release sheet. Made by the company, product name "Iupilon sheet MR58U", thickness: 0.7mm, containing UV absorber), through the plastic sheet, irradiated with active energy rays under the following conditions to harden the colored adhesive layer. Regarding the adhesive of the colored adhesive layer after curing, the gel fraction (after UV) is derived in the same manner as described above.

>Active energy ray irradiation conditions> ‧Using a high-pressure mercury lamp ‧Illuminance 200mW/cm ² , light intensity 2000mJ/cm ² ‧UV illuminance ‧Light meter uses EYE GRAPHICS company "UVPF-A1"

[Test Example 3] (Measurement of Storage Elastic Modulus) The release sheet was peeled off from the colored adhesive sheets obtained in the examples and comparative examples, and a plurality of colored adhesive layers were laminated with a thickness of 3 mm. From the obtained laminated body of the colored adhesive layer, a cylinder with a diameter of 8 mm (height 3 mm) was punched out, and this was used as a sample.

Regarding the above sample, in compliance with JIS K7244-6, using a viscoelasticity measuring device (manufactured by Physica, product name "MCR300"), the storage elastic modulus (MPa) was measured under the following conditions by the torsional shear method. The results are shown in Table 3. Measuring frequency: 1Hz Measuring temperature: 23℃

Furthermore, the colored adhesive sheet of Example 5 was irradiated with active energy rays in the same manner as in Test Example 2 to harden the colored adhesive layer, and the cured colored adhesive layer was also measured for storage elastic modulus as described above. Number (after UV).

[Test Example 4] (Measurement of Haze Value) For the colored adhesive layer of the colored adhesive sheets 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 "SH-7000") in accordance with JIS K7136: 2000 . The obtained total light haze value (%) is shown in Table 3. In addition, the average haze value of the average value of the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm is calculated from the measured value; the difference between the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm; in the wavelength range The standard deviation of the haze value of each wavelength at a 5nm pitch from 380nm to 780nm.

Furthermore, the colored adhesive sheet of Example 5 was irradiated with active energy rays in the same manner as in Test Example 2 to harden the colored adhesive layer, and the total light haze of the cured colored adhesive layer was also measured as described above Value (after UV). Then, calculate the average haze between the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm (after UV) from the measured values; the difference between the haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm (after UV) ); The standard deviation of the haze value of each wavelength (after UV) at the 5nm pitch in the wavelength region of 380nm~780nm. The respective results are shown in Table 3.

[Test Example 5] (Measurement of total light transmittance) The colored adhesive layer of the colored adhesive sheets obtained in the Examples and Comparative Examples were bonded to glass, and this was used as a measurement sample. The background measurement was performed on glass, and the total light transmittance (%) was measured using a haze meter (manufactured by Nippon Denshoku Kogyo Co., Ltd., product name "SH-7000") for the above-mentioned measurement sample in compliance with JIS K7361-1:1997. Furthermore, the colored adhesive sheet of Example 5 was irradiated with active energy rays in the same manner as in Test Example 2 to harden the colored adhesive layer, and the cured colored adhesive layer was also measured for total light transmittance as described above (After UV). The results are shown in Table 3.

[Test Example 6] (L*a*b* measurement) For the colored adhesive layer of the colored adhesive sheets obtained in the Examples and Comparative Examples, the CIE1976L*a*b* color was measured using a simultaneous photometric spectrophotometer (manufactured by Nippon Denshoku Kogyo Co., Ltd., product name "SQ2000") It is the specified lightness L*, chroma a*, and chroma b*. Furthermore, the colored adhesive sheet of Example 5 was irradiated with active energy rays in the same manner as in Test Example 2 to harden the colored adhesive layer, and the lightness L*(UV) of the colored adhesive layer after curing was also measured as described above. After), chromaticity a* (after UV) and chromaticity b* (after UV). The results are shown in Table 3.

[Test Example 7] (Measurement of Adhesion) The light-peelable release sheet was peeled from the colored adhesive sheets obtained in the Examples and Comparative Examples, and the exposed colored adhesive layer was pasted on a polyethylene terephthalate (PET) film with an easy-adhesion layer (Toyobo Co., Ltd. Product name "PET A4300", thickness: 100μm) easy-to-adhesive layer to obtain a laminate of release sheet/colored adhesive layer/PET film. The obtained laminate was cut into a width of 25 mm and a length of 100 mm, and this was used as a sample.

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 an autoclave made by Kurihara Manufacturing Co., Ltd. 0.5MPa, 50℃, pressurized for 20 minutes. Then, after leaving for 24 hours under the conditions of 23°C and 50%RH, the adhesion was measured using a tensile tester (manufactured by Orientec, product name "Tensilon") at a peeling speed of 300 mm/min and a peeling angle of 180 degrees. Force (N/25mm). Conditions other than those described here were measured in compliance with JIS Z0237:2009. The results are shown in Table 3.

In addition, for the colored adhesive sheet of Example 5, the colored adhesive layer was adhered to soda lime glass in the same manner as above, and after autoclave treatment, it was left for 24 hours under the conditions of 23°C and 50%RH, and then In Test Example 2, active energy rays were irradiated in the same manner to harden the colored adhesive layer. The adhesive force (after UV) of the colored adhesive layer after curing was also measured in the same manner as above.

[Test Example 8] (Measurement of the following rate of step difference) On the surface of a glass plate (product name "Corning Glass EAGLE XG" manufactured by NSG Precision Co., Ltd., length 90mm×width 50mm×thickness 0.5mm), UV curable ink (manufactured by Teikoku Printing Inks Mfg, product name "POS-911 BLACK”), screen printing into a frame shape (outer shape: vertical 90mm × horizontal 50mm, width 5mm). Then, irradiate ultraviolet rays (80W/cm2, 2 metal halide lamps, 15cm height of bulb, 10~15m/min of conveyor belt speed) to harden the above-mentioned ultraviolet curable ink for printing, and produce a step with printing (the height of the step: 5μm, 10μm, 15μm, 20μm, 25μm, 50μm, 60μm and 70μm) glass plate with stepped.

In the adhesive sheet obtained from the colored adhesive sheets obtained in the Examples and Comparative Examples, the light-peelable release sheet was peeled off, and the exposed colored adhesive layer was adhered to a polyethylene terephthalate film with an easy-adhesive layer (Toyobo The easy-adhesive layer made by the company, product name "PET A4300", thickness: 100μm). Next, the heavy peeling type release sheet is peeled off to expose the colored adhesive layer. Then, using a laminating machine (manufactured by FUJIPLA, product name "LPD3214"), the colored adhesive layer was used to cover the frame-like printed surface, and the laminate was laminated on a glass plate with steps, and this was used as an evaluation sample .

The obtained evaluation sample was subjected to autoclave treatment under the conditions of 50° C. and 0.5 MPa for 30 minutes, and then left for 24 hours under the conditions of normal pressure, 23° C., and 50% RH. Next, it was stored under high temperature and high humidity conditions of 85° C. and 85% RH for 72 hours (endurance test), and after that, the step followability was evaluated. The step followability is judged based on whether the printing step is completely buried by the colored adhesive layer. When bubbles, floating, peeling, etc. are observed at the interface between the printing step and the colored adhesive layer, it is judged that the printing step cannot be followed. Here, the level difference followability is evaluated by the level difference followability rate (%) shown by the following formula. The results are shown in Table 3. Level difference follow-up rate (%)={(After the durability test, the level difference height (μm) to maintain the state of being buried without bubbles, floating, peeling, etc.)/(the thickness of the colored adhesive layer)}×100

Furthermore, with regard to the colored adhesive sheet of Example 5, a colored adhesive layer with a thickness of 25 μm was prepared, and the resulting evaluation sample was subjected to autoclave treatment in the same manner as above, and then it was left at 23°C and 50% RH for 24 After hours, the active energy ray was irradiated in the same manner as in Test Example 2 to harden the colored adhesive layer. For the colored adhesive layer after curing, the step following rate (after UV) was measured in the same manner as described above.

[Test Example 9] (Design evaluation) The colored adhesive sheets obtained in the Examples and Comparative Examples were cut to a length of 70 mm × width 70 mm, and the colored adhesive layer of the colored adhesive sheet was covered with 2 sheets of soda lime glass (manufactured by Japan Plate Glass Co., Ltd., length 70 mm × width 70 mm × thickness 1.1mm) Glue in a clamping manner, and use this as a sample. In addition, the colored adhesive sheet of Example 5 was irradiated with active energy rays in the same manner as in Test Example 2 to harden the colored adhesive layer, and this was used as a sample.

The obtained sample was set directly in front of a display (manufactured by Fujitsu Corporation, product name "LITEBOOK A574/H", size 15.6 inches, resolution 1366×768) in a light-off state. At this time, the sample is set so that the peripheral edge of the sample is adjacent to the frame material of the display. Then, under a 3-wavelength fluorescent lamp (distance from the fluorescent lamp: 200cm), the color tone of the sample (the degree of black and whiteness) was visually judged, and the design of the color tone of the screen was evaluated based on the following criteria. The results are shown in Table 3. ◎: There is a deep black tone even under the reflection of fluorescent lamps. ○: If there is no reflection from the fluorescent lamp, there is a deep black tone. ╳: The whole looks pale.

In addition, the appearance of the boundary between the sample portion and the frame material of the above-mentioned display was judged visually, and the design of framelessness was evaluated based on the following criteria. The results are shown in Table 3. ◎: The boundary cannot be seen. ○: The boundary can be slightly visualized but is not obvious. ╳: Can clearly see the boundary.

Furthermore, the hue of the display frame material (CIE1976L*a*b* color system) was measured using a spectrophotometer (manufactured by BYK, product name "SPECRO GUIDE"). The result was L*: 19.7, a* : -0.3, b*: -1.5.

[Test Example 10] (Evaluation of visibility) A sample was produced in the same manner as in Test Example 9, and it was installed in front of a display (manufactured by Fujitsu Corporation, product name "LITEBOOK A574/H", size 15.6-inch, resolution 1366×768) in a lighting state. At this time, on the display, ARIB multi-format color bars are displayed. Then, under a three-wavelength fluorescent lamp (distance from the fluorescent lamp: 200cm), the sample was visually judged from the front and inclined surface (45∘ angle), and the look and feel of the display across the sample was evaluated by the following criteria (wide-angle visibility) ). The results are shown in Table 3. ◎: There is no change between the frontal look and the oblique look. ○: Compared with the frontal look, the oblique look becomes darker, but the color tone does not change. ╳: The color tone will change from the frontal look and the oblique look.

Furthermore, in either example, the screen when viewed from the front is bright, so the visibility of the image due to the brightness of the screen is good.

[Table 1] (Meth)acrylate polymer (A) Crosslinking agent (B) Colorant (C) Active energy ray hardening ingredient (D) Photopolymerization initiator (E) Silane coupling agent Colored adhesive layer thickness [μm] ingredient Mw Mass parts species Mass parts Mass parts Mass parts Mass parts Example 1 2EHA/MMA/HEA =70/15/15 800 000 0.2 C1 0.4 - - 0.2 100 Example 2 0.2 C2 0.9 - - 0.2 100 Example 3 2EHA/IBXA/ACMO/HEA =60/10/10/20 600000 0.2 C1 1.5 - - 0.2 25 Example 4 BA/AA/HEA =90/1/9 500000 0.2 C1 1.5 - - 0.2 25 Example 5 2EHA/MMA/HEA =70/15/15 800 000 0.2 C2 1.0 5.0 5.0 0.2 5 Example 6 0.2 C3 0.5 - - 0.2 25 Example 7 0.2 C4 0.5 - - 0.2 25 Example 8 0.2 C5 0.5 - - - 25 Comparative example 1 0.2 - - - - 0.2 25 Comparative example 2 0.2 C6 1.9 - - 0.2 25

[Table 2] Types of colorants 380nm haze value (%) Haze value at 780nm (%) Haze value difference (percentage point) Average haze (%) Standard deviation of haze value C1 25.0 23.7 1.3 24.89 0.48 C2 10.1 2.3 7.8 4.11 1.49 C3 9.6 2.6 7.0 5.31 2.03 C4 19.0 3.8 15.2 9.20 4.31 C5 47.8 20.6 27.2 32.56 7.99 C6 84.9 81.0 3.9 84.66 1.45

[table 3] Visibility evaluation Wide-angle visibility ◎ ◎ ○ ○ ◎ ○ ◎ ╳ ◎ ○ Design evaluation Borderless ◎ ◎ ◎ ◎ ◎ ◎ ◎ ◎ ╳ ◎ Hue of the picture ◎ ◎ ○ ○ ◎ ◎ ◎ ○ ◎ ╳ Segment followability (%) 60 60 60 40 60 40 40 40 40 40 Storage elastic modulus (MPa) 0.13 0.13 0.12 0.13 Before UV: 0.08 After UV: 0.12 0.13 0.13 0.12 0.14 0.14 Adhesion (N/25mm) 26 18 twenty one 41 Before UV: 7 After UV: 8 16 18 16 twenty two twenty one Color system b* 0.5 0.7 0.9 0.9 0.1 5.7 5.2 5.5 0.0 0.2 a* 0.2 -0.6 0.4 0.4 -1.1 1.2 1.2 1.7 0.0 0.6 L* 90.5 86.4 77.5 83.5 84.7 77.1 82.4 60.8 100 77.0 Total light transmittance (%) 77.5 69.8 52.3 63.1 65.3 51.9 61.4 29.2 ≧99 50.2 Haze value Full light haze value (%) 11.2 4.7 28.5 18.3 2.2 6.6 2.9 15.6 0.3 86.6 Standard deviation of haze value 1.6 1.8 2.6 2.8 0.9 2.4 1.4 5.1 0.0 1.7 Average haze (%) 10.9 3.9 27.9 17.8 2.4 6.7 3.0 15.4 0.3 86.8 Haze value difference (percentage point) 5.5 4.9 8.9 9.5 4.6 8.4 5.0 17.8 0.0 2.6 780nm haze value (%) 8.4 1.3 23.3 13.2 1.3 3.5 1.3 8.4 0.3 83.5 380nm haze value (%) 13.9 6.2 32.2 22.7 5.9 11.9 6.3 26.2 0.3 86.1 Gel fraction (%) 68 69 69 68 Before UV: 50 After UV: 67 68 68 69 70 65 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Comparative example 1 Comparative example 2

It can be seen from Table 3 that the use of the colored adhesive sheets obtained in the examples has excellent design properties (especially design properties regarding the hue of the screen) and visibility (especially wide-angle visibility and visibility due to the brightness of the screen). In addition, the colored adhesive sheets obtained in the examples have excellent step followability. [Industrial Profitability]

The colored adhesive sheet of the present invention can be suitably used for, for example, bonding of display device constituent members of a display device with a black frame material, particularly bonding of a protective plate with a step and a desired display device constituent member, etc.

1: Colored adhesive sheet 11: Colored adhesive layer 12a, 12b: peeling sheet 2: display device 21: The first display device component 22: The second display device component 3: Printing layer 4: Frame material

Fig. 1 is a cross-sectional view of a colored adhesive sheet according to an embodiment of the present invention. Fig. 2 is a cross-sectional view of a display device related to an embodiment of the present invention. Fig. 3 is a plan view of a display device having a frame material related to an embodiment of the present invention.

1: Colored adhesive sheet

11: Adhesive layer

12a, 12b: peeling sheet

Claims (13)

A colored adhesive sheet, characterized in that it is provided with a colored adhesive layer composed of an adhesive containing a coloring agent for bonding a display device constituent member and other display device constituent members, The average haze value of the haze value at the wavelength of 780 nm and the haze value at the wavelength of 380 nm of the colored adhesive layer is 1% or more and 60% or less. The colored adhesive sheet according to claim 1, wherein the difference between the haze value of the colored adhesive layer at a wavelength of 780 nm and the haze value at a wavelength of 380 nm is 15% or less. The colored adhesive sheet according to claim 1, wherein the standard deviation of the haze value of the colored adhesive layer at each wavelength at a pitch of 5 nm in the wavelength region of 380 nm to 780 nm is 5 or less. The colored adhesive sheet according to claim 1, wherein the total light transmittance of the colored adhesive layer is more than 10% and less than 95%, and the CIE1976L*a*b* color system of the colored adhesive layer The specified chromaticity a* and chromaticity b* are -7~7 respectively. The colored adhesive sheet according to claim 1, wherein the colorant is a liquid diluted 10,000 times with ethyl acetate, and the average haze value of the average haze value at the wavelength of 780nm and the haze value at the wavelength of 380nm It is 1% or more and 60% or less. The colored adhesive sheet according to claim 1, wherein the colorant is a liquid diluted 10,000 times with ethyl acetate, and the difference between the haze value at a wavelength of 780nm and the haze value at a wavelength of 380nm is less than 30% . The colored adhesive sheet according to claim 1, wherein the colorant is a black pigment. The colored adhesive sheet according to claim 1, wherein the adhesive is an acrylic adhesive. The colored adhesive sheet according to claim 1, wherein the adhesive is an adhesive composition containing a (meth)acrylate polymer (A), a crosslinking agent (B), and a coloring agent (C) Become. The colored adhesive sheet as described in claim 1, which has: 2 peel-off sheets; and The colored adhesive layer which is sandwiched by the peeling sheet is held by the peeling surfaces of the two peeling sheets. A display device, characterized in that it is a display device with the following: A component of the display device; Other display device components; and A colored adhesive layer for bonding the one display device constituent member and the other display device constituent members to each other, wherein The colored adhesive layer is the colored adhesive layer of the colored adhesive sheet described in any one of claims 1-10. The display device according to claim 11, wherein at least one of the one display device constituent member and the other display device constituent member has a level difference at least on the side where the colored adhesive layer is bonded. The display device described in claim 11 has a black frame material.

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