JPWO2013065662A1 - Heat ray shielding adhesive composition and heat ray shielding adhesive sheet - Google Patents

Abstract

An object of the present invention is to efficiently shield not only the infrared region but also the heat rays in the near infrared region. The present invention relates to a heat ray-shielding pressure-sensitive adhesive composition containing (A) metal fine particles, (B) an acrylic pressure-sensitive adhesive, (C) a dispersant, and (D) a near-infrared absorbing dye, and A heat ray-shielding pressure-sensitive adhesive sheet is provided. [Selection figure] None

Description

  The present invention relates to a heat ray-shielding pressure-sensitive adhesive composition that can be attached to a window glass or the like and can efficiently shield heat rays, and a heat ray-shielding pressure-sensitive adhesive sheet using the same.

  In recent years, from the viewpoint of energy saving and global environmental problems, it has been demanded to reduce the load on air conditioning equipment. For example, in the field of houses and automobiles, it is required to apply a heat ray shielding material capable of shielding heat rays from sunlight to the window glass to suppress the temperature rise in the room or in the vehicle. Although there are various materials having heat ray shielding properties, Patent Literature 1 discloses a pressure-sensitive adhesive imparted with heat ray shielding properties and an adhesive sheet thereof. This pressure-sensitive adhesive sheet is obtained by processing a pressure-sensitive adhesive having heat ray shielding properties into a sheet shape, and can be processed into an arbitrary shape in advance and has reworkability that enables re-stretching. However, the pressure-sensitive adhesive sheet imparted with the heat ray shielding property is insufficient in the heat shielding property, and further improvement is desired.

Japanese Patent Application No. 10-8010

  It is an object of the present invention to provide a heat ray-shielding pressure-sensitive adhesive composition and a heat ray-shielding pressure-sensitive adhesive sheet that have greatly improved heat ray-shielding properties compared to conventional heat-ray-shielding pressure-sensitive adhesive sheets.

  As a result of intensive studies to obtain a heat ray-shielding pressure-sensitive adhesive sheet having greatly improved heat ray-shielding properties, the present inventors have found that metal fine particles including tin-doped indium oxide, near-infrared absorbing dyes, dispersants and pressure-sensitive adhesives. The heat-ray-shielding pressure-sensitive adhesive composition capable of efficiently shielding heat rays and a heat-ray-shielding pressure-sensitive adhesive sheet obtained by processing the same into a sheet, thereby completing the present invention. .

That is, the present invention
“(1) (A) Metal fine particles, (B) Acrylic adhesive, (C) Dispersant, and (D) Heat ray-shielding adhesive composition containing near-infrared absorbing dye,
(2) (A) The heat ray shielding pressure-sensitive adhesive composition according to (1), wherein the metal fine particles are a kind of metal fine particles selected from the group consisting of tin oxide, indium oxide, and zinc oxide,
(3) (B) The acrylic pressure-sensitive adhesive is a polymer in which the proportion of structural units of a carboxy group or an acid anhydride-containing monomer is 1 to 5% of all monomer structural units in the polymer ( 1) or the heat ray shielding adhesive composition according to any one of (2),
(4) The heat ray-shielding pressure-sensitive adhesive composition according to any one of (1) to (3), wherein the weight average molecular weight of the acrylic pressure-sensitive adhesive is 100,000 to 1,200,000,
(5) (D) The heat ray according to any one of (1) to (4), wherein the near-infrared absorbing dye is a phthalocyanine compound, a naphthalocyanine compound, and / or a diimonium compound. Shielding adhesive composition,
(6) (D) The heat ray-shielding pressure-sensitive adhesive composition according to (5), wherein the near-infrared absorbing dye is a naphthalocyanine compound represented by the formula (1),

［式（１）中、Ｍは金属原子、金属酸化物、金属水酸化物、若しくは金属ハロゲン化物、又は水素原子を表し、Ｘは低級アルキル基、低級アルコキシ基、置換アミノ基、ニトロ基、ハロゲン基、ヒドロキシ基、カルボキシ基、スルホン酸基、スルホンアミド基を表す。Ａは二価の架橋基を、Ｙはスルホン酸基、カルボキシ基、第１〜２級アミノ基の窒素原子上の水素の少なくとも１つを除いた残基、又は窒素を含む複素環の窒素原子上の水素の少なくとも１つを除いた残基を表す。ｍ及びｎはいずれも平均値であり、ｍ、ｎはそれぞれ０以上１２以下、かつ、ｍとｎとの和は０以上１２以下である。］
（７）式（１）中のＭはＶＯであり、Ａは炭素数１〜３のアルキレン基であり、Ｙは置換基を有してもよいフタルイミド基である（６）に記載の熱線遮蔽性粘着剤組成物、
（８）式（１）中のＭはＣｕであり、Ａは炭素数１〜３のアルキレン基であり、Ｙは置換基を有してもよいフタルイミド基である（６）に記載の熱線遮蔽性粘着剤組成物、
（９）（１）乃至（８）の何れか一項に記載の熱線遮蔽性粘着剤組成物を塗布してなる熱線遮蔽性粘着シート」に関する。

[In the formula (1), M represents a metal atom, a metal oxide, a metal hydroxide, a metal halide, or a hydrogen atom, and X represents a lower alkyl group, a lower alkoxy group, a substituted amino group, a nitro group, a halogen atom. Represents a group, a hydroxy group, a carboxy group, a sulfonic acid group, or a sulfonamide group. A is a divalent bridging group, Y is a sulfonic acid group, a carboxy group, a residue obtained by removing at least one of hydrogen on the nitrogen atom of the primary or secondary amino group, or a nitrogen atom of a heterocyclic ring containing nitrogen Represents a residue excluding at least one of the above hydrogens. m and n are both average values, m and n are each 0 or more and 12 or less, and the sum of m and n is 0 or more and 12 or less. ]
(7) M in Formula (1) is VO, A is an alkylene group having 1 to 3 carbon atoms, and Y is a phthalimide group which may have a substituent. Adhesive composition,
(8) M in formula (1) is Cu, A is an alkylene group having 1 to 3 carbon atoms, and Y is a phthalimide group which may have a substituent. Adhesive composition,
(9) It is related with the heat ray shielding adhesive sheet formed by apply | coating the heat ray shielding adhesive composition as described in any one of (1) thru | or (8).

  According to the present invention, a heat ray-shielding pressure-sensitive adhesive composition in which metal fine particles including tin-doped indium oxide and a near-infrared absorbing dye are dispersed in an acrylic pressure-sensitive adhesive using a dispersant is processed into a sheet shape. Thereby, compared with the conventional heat ray shielding adhesive sheet, the heat ray shielding adhesive sheet which can suppress the temperature rise by a heat ray more can be provided. Thereby, the temperature rise of the space of a house or a car can be suppressed, and the load on the air conditioner can be reduced. Therefore, the present invention can contribute to energy saving and the solution of global environmental problems.

  The present invention will be described in detail. The pressure-sensitive adhesive composition for forming a heat ray-shielding pressure-sensitive adhesive sheet according to the present invention is characterized in that metal fine particles including tin-doped indium oxide and a near-infrared absorbing dye are dispersed in an acrylic pressure-sensitive adhesive using a dispersant. The pressure-sensitive adhesive composition can be processed into a sheet shape.

  As the metal fine particles used in the heat ray-shielding pressure-sensitive adhesive composition, those having low absorption of visible light and having good absorption characteristics for light in the near infrared to far infrared region are suitable. As such a thing, the electroconductive metal oxide which has a plasma wavelength in a near-infrared region is mentioned. Specific examples include tin oxide, indium oxide, zinc oxide, tungsten oxide, chromium oxide, and molybdenum oxide. Of these, tin oxide, indium oxide, and zinc oxide, which have a small light absorption property particularly in the visible light region, are preferable.

  In addition, it is very preferable to dope the third component in order to improve the electrical conductivity of these oxides. As the dopant for this, Sb, V, Nb, Ta, etc. are selected for tin oxide, Zn, Al, Sn, Sb, Ga, Ge, etc. are selected for indium oxide, and zinc oxide is used. For this, Al, Ga, In, Sn, Sb, Nb or the like is selected.

  The method for producing the metal fine particles is not particularly limited as long as a particle size of 100 nm or less is obtained, and known methods such as a gas phase synthesis method and a liquid layer synthesis method can be used. For example, for indium oxide fine particles, the method disclosed in JP-A-6-227815 can be used. That is, this is a method of obtaining metal fine particles by neutralizing an aqueous solution of a salt containing a specific metal fine particle element with an alkali, filtering and washing the obtained precipitate, and heat-treating it at a high temperature. Examples of the tin oxide fine particles and the zinc oxide fine particles include JP-A-2-105875 and JP-A-6-234522, respectively.

  A conventional method can be used as a method of dispersing the metal fine particles in the organic solvent. That is, metal fine particles and an organic solvent are mixed at a predetermined ratio, and a dispersant, a surfactant, etc. are added to this mixture as necessary, and the mixture is used using a dispersing device such as a sand mill, attritor, ball mill, homogenizer, roll mill, etc. Can be dispersed.

  In the metal fine particles of the present invention, the half width of the first main peak obtained by the XRD pattern is 0.01 to 0.8 °, and when the half width is 0.01 ° or less, the primary particle diameter becomes large. Therefore, it is difficult to ensure transparency. Moreover, when the half width exceeds 0.8 °, it is difficult to develop sufficient heat shielding properties. The metal fine particles have a preferred lower limit of the half width of 0.1 °, a preferred upper limit of more than 0.8 °, a preferred lower limit of 0.2, and a more preferred upper limit of 0.5 °.

Metal fine particles used in the present invention, preferably the measured specific surface area is 5 to 200 m ³ / g by the BET method, more preferably from 10 to 150 m ³ / g, particularly preferably 10 to 100 m ³ / g is there. Those having a specific surface area of less than 5 m ³ / g by the BET method have a large primary particle size, and therefore, when a sheet, film, paint or resin composition is used, the finished surface may not be smooth. Furthermore, there is a risk that disadvantages such as the inability to expect transparency can occur. On the other hand, when the BET specific surface area is larger than 200 m ³ / g, a special technique is required for production, and sufficient crystallinity cannot be obtained, which may impair heat ray shielding. The BET method is a method in which a specific surface area of a sample is measured based on the amount of molecules and ions having a known size adsorbed on the powder particle surface.

  The near-infrared absorbing dye is a general term for dyes that absorb the near-infrared ray (wavelength of about 780 to 2000 nm) that is the closest to the visible region, and the types of near-infrared absorbing dyes are azo, aminium, and anthra. Examples include quinone, cyanine, diimonium, dithiol metal complex, squarylium, phthalocyanine, and naphthalocyanine. From the viewpoint of increasing durability, phthalocyanine-based, naphthalocyanine-based, and diimonium-based are preferable, and from the viewpoint of efficiently blocking heat rays, naphthalocyanine-based is preferable, and the compound represented by the formula (1) is particularly preferable. . In the formula (1), M represents a hydrogen atom, a metal atom, a metal oxide, a metal hydroxide, or a metal halide. When M is other than a hydrogen atom, the M means that the naphthalocyanine ring in the formula (1) has a so-called central metal. Further, when M is a hydrogen atom, it means that the naphthalocyanine ring does not have a central metal.

  Specific examples of the metal atom in M include, for example, Li, Na, K, Mg, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Ru, Rh, Pd, Examples include Os, Ir, Pt, Cu, Ag, Au, Zn, Cd, Hg, Al, Ga, In, Si, Ge, Sn, Pb, Sb, and Bi.

Examples of the metal oxide include VO and GeO. Examples of the metal hydroxide include Si (OH) ₂ , Cr (OH) ₂ , Sn (OH) ₂ , AlOH and the like. As the metal halide, for _{example, SiCl 2, VCl, VCl 2} , VOCl, FeCl, GaCl, ZrCl, AlCl , and the like. Among these, metal atoms such as Fe, Co, Cu, Ni, Zn, Al, and V, metal oxides such as VO, metal hydroxides such as AlOH, and the like are preferable, and Cu and VO are more preferable.

  The M is Li, Na, K, Mg, Ti, Zr, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, Cu, Ag. , Au, Zn, Cd, Hg, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi A heat-shielding adhesive sheet prepared using a toluene dispersion of a naphthalocyanine-based compound In the property test, the temperature inside the box used for the test was lowered, and a good heat ray shielding effect was shown. In particular, when a naphthalocyanine-based compound in which M is Cu is used, the temperature in the box is remarkably reduced, and an excellent heat ray heat shielding effect is exhibited, which is preferable. A naphthalocyanine-based compound in which M is VO is also preferable because it significantly reduces the temperature in the box and exhibits an excellent heat-ray heat shielding effect.

X represents a lower alkyl group, a lower alkoxy group, a substituted amino group, a nitro group, a halogen group, a hydroxy group, a carboxy group, a sulfonic acid group or a sulfonamide group. A is a divalent bridging group, for example, an alkylene group having 1 to 3 carbon atoms, —CO ₂ —, —SO ₂ —, —SO ₂ NH (CH ₂ ) _a — (where a represents 0 to 4). The alkylene group having 1 to 3 carbon atoms and —SO ₂ NH— in which a is 0 are preferable, and the alkylene group having 1 to 3 carbon atoms is more preferable. Y represents a sulfonic acid group, a carboxy group, a residue excluding at least one hydrogen on the nitrogen atom of the primary or secondary amino group, or at least one hydrogen on the nitrogen atom of the heterocyclic ring containing nitrogen. Represents a removed residue, such as a carboxy group, a sulfonic acid group, a phthalimide group which may have a substituent, a piperazino group which may have a substituent, a piperidino group which may have a substituent, etc. The phthalimide group which may have a carboxy group, a sulfonic acid group and a substituent is preferable, and a phthalimide group which may have a substituent is more preferable. In addition, when Y is a phthalimide group that may have a substituent, a piperazino group that may have a substituent, or a piperidino group that may have a substituent, the substituent may be a hydrogen atom or a lower alkyl group. , A lower alkoxy group, a substituted amino group, a nitro group, a halogen group and a sulfonic acid group, preferably a hydrogen atom or a halogen group.

  In the present invention, the substituted amino group is not particularly limited, and examples thereof include an amino group substituted with a lower alkyl group. Moreover, a lower alkyl group and a lower alkoxy group point out a linear or branched C1-C4 alkyl group and alkoxy group, respectively. A conventional method can be used as a method of dispersing the near-infrared absorbing dye in an organic solvent. That is, a near-infrared absorbing dye and an organic solvent are mixed in a predetermined ratio, and a dispersant, a surfactant, etc. are added to this mixture as necessary, and a dispersing device such as a sand mill, an attritor, a ball mill, a homogenizer, or a roll mill is added. Can be used to disperse the mixture.

  The heat ray-shielding pressure-sensitive adhesive composition in which the metal fine particles and the near-infrared absorbing dye are dispersed and the heat ray-shielding pressure-sensitive adhesive sheet obtained by processing this composition into a sheet shape are attached to the window glass, and are included in the wavelength included in sunlight. Therefore, the first condition is that the weather resistance is good. Therefore, the pressure-sensitive adhesive resin used in this embodiment is preferably an acrylic copolymer pressure-sensitive adhesive resin with good weather resistance. The acrylic copolymer-based pressure-sensitive adhesive can be usually produced by copolymerization of a main monomer having a low glass transition point and a comonomer having a high glass transition point.

  As a monomer as a main component of the acrylic copolymer-based pressure-sensitive adhesive, an acrylic acid alkyl ester having a low glass transition point and an alkyl group having 2 to 14 carbon atoms or an alkyl group having 4 to 16 carbon atoms is used. A monomer having a glass transition point higher than them and copolymerizable therewith is used together with the main monomer.

  Examples of acrylic acid alkyl ester monomers having a low glass transition point include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, methoxyethyl acrylate, n-butyl actylate, isobutyl acrylate, secondary butyl acrylate, acrylic acid 2 -Ethylhexyl, n-octyl acrylate, isooctyl acrylate, isononyl acrylate, isostearyl acrylate, and the like.

  Examples of the methacrylic acid alkyl ester monomer having a low glass transition point include 2-ethylhexyl methacrylate, n-octyl methacrylate, and n-lauryl methacrylate.

  Examples of the copolymerizable monomer include vinyl acetate, acrylonitrile, acrylamide, styrene, methyl methacrylate, methyl acrylate, and the like.

  In order to obtain the required adhesion performance in addition to the above monomers, (meth) acrylic acid, itaconic acid, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, acrylic as functional group-containing monomers Amide, methylol acrylamide, dimethylacrylamide, glycidyl methacrylate, maleic anhydride and the like are also used.

  Further, since the molecular weight greatly affects the dispersibility of the metal fine particles and the near-infrared absorbing dye, the weight average molecular weight of the acrylic pressure-sensitive adhesive is preferably 100,000 to 1,200,000. More preferably, it is 200,000 to 800,000.

  The degree of crosslinking of the polymer material constituting the pressure-sensitive adhesive varies depending on various conditions such as the type and composition of the pressure-sensitive adhesive (pressure-sensitive adhesive composition), and is not particularly limited. If necessary, the pressure-sensitive adhesive composition may contain a plasticizer. As this plasticizer, esters such as phthalic acid ester, trimellitic acid ester, pyromellitic acid ester, adipic acid ester, sebacic acid ester, phosphoric acid triester or glycol ester, process oil, liquid polyether, liquid polyterpene, Other liquid resin etc. are mentioned, Among these, 1 type or 2 types or more can be mixed and used. Such a plasticizer is preferably one having good compatibility with the pressure-sensitive adhesive. Moreover, the adhesive composition can contain various additives, such as a ultraviolet absorber or antioxidant, as needed, in addition to the plasticizer.

  Dispersants include fatty acid salts (soap), α-sulfo fatty acid ester salts (MES), alkylbenzene sulfonates (ABS), linear alkylbenzene sulfonates (LAS), alkyl sulfates (AS), alkyl ether sulfates Low molecular weight anionic (anionic) compounds such as salt (AES) and alkyl sulfate triethanol, fatty acid ethanolamide, polyoxyethylene alkyl ether (AE), polyoxyethylene alkylphenyl ether (APE), sorbitol, sorbitan Nonionic compounds, low molecular weight cationic (cationic) compounds such as alkyltrimethylammonium salt, dialkyldimethylammonium chloride, alkylpyridinium chloride, alkylcarboxyl betaine, sulfobetatai Low molecular amphoteric compounds such as lecithin, formalin condensate of naphthalene sulfonate, polystyrene sulfonate, polyacrylate, copolymer salt of vinyl compound and carboxylic acid monomer, carboxymethyl cellulose, polyvinyl alcohol, etc. Typical examples are polymeric water-based dispersants such as polyacrylic acid partial alkyl esters and polyalkylene polyamines, and polymer cationic dispersants such as polyethyleneimine and aminoalkyl methacrylate copolymers. However, as long as it is suitably applied to the particles of the present invention, those having a structure other than the ones exemplified here are not excluded.

  The following are known as specific dispersants. That is, Floren DOPA-15B, Floren DOPA-17 (manufactured by Kyoeisha Chemical Co., Ltd.), Solplus AX5, Solplus TX5, Solsperse 9000, Solsperse 12000, Solsperse 17000, Solsperse 20000, Solsperse 21000, Solsperse 24000, Solsperse 26000, Solsperse 27000, Solsperse 28000, Solsperse 32000, Solsperse 35100, Solsperse 54000, Sol Six 250, (manufactured by Nippon Lubrizol Corporation), EFKA4008, EFKA4009, EFKA4010, EFKA4015, EFKA4046, EFKA4047, EFKA4060, EFKA4080, EFKA4080, EFKA4080, EFKA4080, EFKA4080 055, EFKA4400, EFKA4401, EFKA4402, EFKA4403, EFKA4300, EFKA4330, EFKA4340, EFKA6220, EFKA6225, EFKA6700, EFKA6780, EFKA6782, EFKA8503, EFKA8503, EFKA8503 Famex L-12 (manufactured by Ajinomoto Fine Techno Co., Ltd.), TEXAPHOR-UV21, TEXAPHOR-UV61 (manufactured by Cognis Japan Co., Ltd.), DisperBYK101, DisperBYK102, DisperBYK106, DisperBYK108, DisperBYK111, Dispe BYK116, DisperBYK130, DisperBYK140, DisperBYK142, DisperBYK145, DisperBYK161, DisperBYK162, DisperBYK163, DisperBYK164, DisperBYK166, DisperBYK167, DisperBYK168, DisperBYK170, DisperBYK171, DisperBYK174, DisperBYK180, DisperBYK182, DisperBYK192, DisperBYK193, DisperBYK2000, DisperBYK2001, DisperBYK2020, DisperBYK2025, DisperBYK2050, DisperBYK2070, DisperBY K2155, DisperBYK2164, BYK220S, BYK300, BYK306, BYK320, BYK322, BYK325, BYK330, BYK340, BYK350, BYK377, BYK378, BYK380N, BYK410, BYK425, BYK Spa, BYK425, BYK425, SPA , Disparon 1860, Disparon 1934, Disparon DA-400N, Disparon DA-703-50, Disparon DA-725, Disparon DA-705, Disparon DA-7301, Disparon DN-900, Disparon NS-5210, Disparon NVI-8514L, Hip Lard ED-152, Hip Lard D-216, Hiprad ED-251, Hiprad ED-360 (Enomoto Kasei Co., Ltd.), FTX-207S, FTX-212P, FTX-220P, FTX-220S, FTX-228P, FTX-710LL, FTX-750LL, Aftergent 212P, Aftergent 220P, Aftergent 222F, Aftergent 228P, Aftergent 245F, Aftergent 245P, Aftergent 250, Aftergent 251, Aftergent 710FM, Aftergent 730FM, Aftergent 730LL, Aftergent 730LS, Aftergent 750DM, aftergent 750FM (manufactured by Neos Co., Ltd.), AS-1100, AS-1800, AS-2000 (manufactured by Toagosei Co., Ltd.), Kaosela 200 , Kaosela 2100, KDH-154, MX-2045L, Homogenol L-18, Homogenol L-95, Rheodor SP-010V, Rheodor SP-030V, Rheodor SP-L10, Rheodor SP-P10 (manufactured by Kao Corporation), Evan U103 , Cyanol DC902B, Neugen EA-167, BRYSURF A219B, BRYSURF AL (Daiichi Kogyo Seiyaku Co., Ltd.), Megafuck F-477, MegaFuck 480SF, MegaFuck F-482, (DIC Corporation), Sil Face SAG503A, Dinol 604 (manufactured by Nissin Chemical Industry Co., Ltd.), SN spurs 2180, SN spurs 2190, SN leveler S-906 (manufactured by San Nopco Co., Ltd.), S-386, S-420 (manufactured by AGC Seimi Chemical Co., Ltd.) Toi Can be illustrated.

  Generally, the smaller the RED (relative energy difference) of the metal fine particles and the dispersant, the better the dispersibility, and a combination of 1.5 or less is preferable. Dispersants with a RED of 1.5 or less with metal fine particles include DISPERBYK-116, DISPERBYK-142, DISPERBYK-145, DISPERBYK-163, DISPERBYK-2000, DSPERBYK-2155, BYK-P105, ANTI-TERRA U, Examples thereof include EFKA-4010 and DOPA-17HF.

  Hansen's proposed solubility parameter shown in Equation 1 in consideration of the dispersion force, dipole interaction, and hydrogen bond effects involved in the Hildebrand solubility parameter (δ), δD (contribution by dispersion force) Known as the contribution from London or van der Waals forces caused by the formation of dipoles induced by molecular collisions), δP (contributions from polar interactions; targeted when molecules are present in solution ΔH (contribution by hydrogen bond; represents a specific interaction, for example, contribution by hydrogen bond, acid / base bond and donor / acceptor bond) is calculated. Further, the interaction radius R0 and the HSP distance Ra are calculated using Equation 2, and from Equation 3, R0 and Ra, RED (Re ative Enelgy Difference) can be calculated.

  The heat ray shielding adhesive composition can be prepared by a known method. For example, the target heat ray-shielding pressure-sensitive adhesive composition can be obtained by dispersing metal fine particles or near-infrared absorbing dyes in a monomer that is a main component of an acrylic copolymer-based pressure-sensitive adhesive and then polymerizing it. In addition, as disclosed in Patent Document 1, there is a method in which a dispersion liquid of metal fine particles or near infrared absorbing dye is prepared in advance, mixed with a monomer, and then polymerized and then a desired pressure-sensitive adhesive is obtained. As a simpler method, there is a method of obtaining a desired pressure-sensitive adhesive composition by directly mixing a dispersion of metal fine particles or a near-infrared absorbing dye with a pressure-sensitive adhesive. The pressure-sensitive adhesive composition can also be obtained by mixing metal fine particles and a near-infrared absorbing dye with a dispersant and dispersing the mixture in the pressure-sensitive adhesive.

  In the production of the heat ray-shielding pressure-sensitive adhesive sheet, the method of applying the pressure-sensitive adhesive is not particularly limited, but use of a comma coater, bar coater, spin coater, spray coater, roll coater, gravure coater, knife coater or other various coating apparatuses Is possible.

  The dispersion ratio of the metal fine particles and the near-infrared absorbing dye to the monomer of the acrylic copolymer pressure-sensitive adhesive or the pressure-sensitive adhesive is determined by the coating thickness of the pressure-sensitive adhesive layer and the shielding performance. The ideal optical performance of a film coated with a heat-shielding pressure-sensitive adhesive is high in visible light transmittance and low in solar radiation transmittance. The optical performance is determined depending on whether or not to do so.

  A film coated with this heat-shielding pressure-sensitive adhesive was actually applied to window glass of buildings and automobiles, and the effects in summer and winter were measured. It has been concluded that the visible light transmittance should be 50% or more in order to minimize the increase in lighting costs and heating costs in winter. Therefore, the optical characteristics of the film coated with the heat ray-shielding pressure-sensitive adhesive are preferably such that the visible light transmittance is 50% or more and the solar radiation transmittance is 80% or less.

  In general, the coating thickness of the pressure-sensitive adhesive layer is usually 10 to 50 μm in consideration of the followability to the adherend surface, the adhesive strength and the economy, but the fine particles that give the above-mentioned heat ray shielding properties within this range The amount of (metal fine particles + near infrared absorbing dye): resin solid content = 3: 97 to 1: 1 (weight ratio) is preferable. If the proportion of the heat ray shielding fine particles is smaller than this, a film thickness of 50 μm or more is required to obtain the necessary heat ray shielding properties. On the other hand, if the proportion is larger than this, the visible light transmittance becomes too small. It is. Furthermore, the haze value of the film needs to be such that the transparency of the glass is not impaired, and should be 8% or less, more preferably 3% or less.

  The present invention will be specifically described with reference to the following examples and comparative examples, but the present invention is not limited thereto.

Synthesis example 1 (metal fine particles)
5.9 g of stannic chloride (SnCl ₄ .5H ₂ O) and 75.9 g of indium chloride (InCl ₃ ) are dissolved in 4000 ml of water, to which 2% aqueous ammonia is added over 58 minutes, and the pH is finally adjusted. In this case, a hydrate of tin oxide and indium oxide was coprecipitated to 7.85. During this time, the liquid temperature was maintained at 5 ° C. Next, the coprecipitate was washed and dried, and further calcined at 900 ° C. for 2 hours to obtain tin-containing indium oxide (ITO) fine powder (metal fine particles).

Synthesis Example 2 (Near-infrared absorbing dye)
3.9 parts of vanadyl 2,3-naphthalocyanine (manufactured by Aldrich), 5.0 parts of phthalimide (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1.0 part of paraformaldehyde are added to 40 parts of polyphosphoric acid and stirred at 140 ° C. for 8 hours. Then, it was poured into 300 parts of water, and the precipitated solid was filtered to obtain 7.5 parts of a naphthalocyanine compound.

Production Example 1 (Metal fine particle dispersion)
To a 7 ml toluene solution was added 1.12 g ITO synthetic particles obtained in Synthesis Example 1, 0.7 g acetylacetone, and 0.175 g dispersant DispersBYK140, and a batch type bead milling device (TK Fillmix 30-25, Primix ( The product was put into a crushing container manufactured by Co., Ltd. Zirconia beads having an average particle size of 30 μm were used as the crushing beads, and the crushing beads were filled up to 35% of the grinding container volume. The crushing was performed under the condition that the motor was set so that the peripheral speed was 6.8 m / s and the crushing time was 10 minutes. Further, the obtained dispersion (metal fine particle dispersion) was centrifuged for 15 minutes at a rotational speed of 5000 rpm using a centrifuge (Hitachi Koki Co., Ltd. Himac CR18).

Production Example 2 (Near-infrared absorbing dye dispersion 1)
0.21 g of the near-infrared absorbing dye obtained in Synthesis Example 2 and 0.21 g of the dispersing agent DisperBYK140 were added to 7 ml of a toluene solution, and a batch type bead milling device (TK Fillmix 30-25 type, manufactured by Primix Co., Ltd.) ). Zirconia beads having an average particle diameter of 30 μm were used as the crushing beads, and the crushing beads were filled up to 70% of the crushing vessel volume. The crushing was performed under the condition that the motor was set so that the peripheral speed was 10 m / s and the crushing time was 30 minutes. Moreover, the near-infrared absorption pigment | dye dispersion liquid 1 was obtained by centrifuging the obtained dispersion for 15 minutes at 5000 rpm with a centrifuge (Hitachi Koki Co., Ltd. Himac CR18).

Production Example 3 (Near-infrared absorbing dye dispersion 2)
A near-infrared pigment dispersion 2 was obtained in the same manner as in Production Example 2 except that the near-infrared absorbing pigment obtained in Synthesis Example 2 was replaced with 2,3-naphthalocyanine (manufactured by Aldrich).

Synthesis example 3 (acrylic adhesive A)
291 g of n-butyl acrylate and 9 g of acrylic acid as monomers are dissolved in 366 g of toluene, 0.15 g of azobisisobutyronitrile is added, and these monomers are polymerized at 70 ° C. for 6 hours under a nitrogen stream. An acrylic resin copolymer (weight average molecular weight: Mw = 320,000) was obtained. Further, the resultant was diluted with toluene to obtain an acrylic resin copolymer solution having a solid content of 29.36% and a viscosity of 2700 mPas.

Production Example 1 of heat ray shielding adhesive and heat ray shielding adhesive sheet
100 parts by weight of acrylic adhesive A obtained in Synthesis Example 3 (butyl acrylate: acrylic acid = 97: 3), 144 parts by weight of toluene dispersion of tin-containing indium oxide (ITO) obtained in Production Example 1, Production Example 14.7 parts by weight of the toluene dispersion of the near-infrared absorbing dye obtained in 2 was mixed and dissolved in a uniform manner to obtain a heat ray shielding adhesive. In addition, this is a release sheet polyester film (silicone treatment on one side) (manufactured by Lintec)
3811 (thickness: 38 μm), coated with a comma coater and dried, release sheet polyester film (one side coated with silicone) (manufactured by Lintec)
3801 (thickness: 38 μm) to produce a heat ray shielding adhesive sheet (thickness: 15 μm).

Example 2
A heat ray-shielding pressure-sensitive adhesive and a heat ray-shielding pressure-sensitive adhesive sheet were produced in the same manner as in Example 1, except that the toluene dispersion of the near-infrared absorbing dye was changed to that produced in Production Example 3.

Comparative Example 1
In Example 1, 144 parts by weight of the toluene dispersion of tin-containing indium oxide (ITO) obtained in Production Example 1 and 100 parts by weight of acrylic adhesive A were used without mixing the toluene dispersion of the near infrared absorbing dye. A heat ray shielding adhesive sheet (thickness: 15 μm) was prepared in the same manner as Example 1 except for the above.

Example 3
A heat ray shielding test was conducted on the heat ray shielding adhesive sheets produced in Example 1, Example 2 and Comparative Example 1 by the method shown below. The results are shown in Table 1.
Test method Test environment: A test box having an inner diameter width of 150 mm, a length of 235 mm, and a height of 110 mm and having an outside air-blocking property and airtightness is prepared. Co., Ltd.) was installed at a height of 40 cm from the ceiling of the test box to constitute a test apparatus for evaluating thermal insulation. Next, the heat ray shielding adhesive sheet produced in the ceiling part of the test box was installed, and the four sides were fixed with tape. In addition, a thermometer was installed in the center of the test box so that the light from the lamp was not directly applied. Thereafter, the lamp was turned on, the temperature was measured every 10 seconds, and the temperature in the test box after 30 minutes was measured. The test box was installed in a room at about 25 ° C. In this test, the temperature inside the box when the heat ray shielding adhesive sheet prepared in the comparative example and the heat ray shielding adhesive sheet of the present invention were used was compared, and the temperature inside the box using the heat ray shielding adhesive sheet of the present invention was low. In this case, the heat ray shielding effect is improved. In addition, the calculation method of the temperature difference in a box is guide | induced by subtracting the temperature in a box using the heat ray shielding adhesive sheet of this invention from the temperature in the box using the heat ray shielding adhesive sheet produced by the comparative example.

  As shown in Table 1, the temperature in the box when using the heat ray shielding adhesive sheet prepared in Comparative Example 1 was 72.5 ° C. On the other hand, the temperature in the box at the time of using the heat ray shielding adhesive sheet produced in Example 1 and Example 2 of the present invention was 68.4 ° C. and 68.0 ° C., respectively. That is, the temperature in the box of the heat ray shielding adhesive sheet produced in Example 1 and Example 2 of the present invention was 4.1 ° C. and 4.5 ° C., respectively, than the temperature in the box of the heat ray shielding adhesive sheet produced in the comparative example. ℃ was low. From this result, it became clear that the heat ray shielding adhesive sheet of the present invention has an improved heat ray shielding effect.

  In the present invention, heat ray-shielding metal fine particles and near-infrared absorbing dye are dispersed in a pressure-sensitive adhesive using a dispersant, thereby suppressing a temperature rise due to heat rays as compared with a conventional heat-ray-shielding pressure-sensitive adhesive sheet. it can. Thereby, this invention can suppress the temperature rise of the space of a house or a motor vehicle, can reduce the load of an air-conditioning apparatus, and can contribute to energy saving and a global environmental problem.

Claims (9)

  A heat ray-shielding pressure-sensitive adhesive composition containing (A) metal fine particles, (B) an acrylic pressure-sensitive adhesive, (C) a dispersant, and (D) a near-infrared absorbing dye.   (A) The heat ray-shielding pressure-sensitive adhesive composition according to claim 1, wherein the metal fine particles are one kind of metal fine particles selected from the group consisting of tin oxide, indium oxide and zinc oxide.   (B) The acrylic pressure-sensitive adhesive is a polymer in which the proportion of structural units of a carboxy group or an acid anhydride-containing monomer is 1 to 5% of all monomer structural units in the polymer. The heat ray shielding adhesive composition as described in any one of 2.   (B) The heat-shielding pressure-sensitive adhesive composition according to any one of claims 1 to 3, wherein the acrylic pressure-sensitive adhesive has a weight average molecular weight of 100,000 to 1,200,000.   (D) The near-infrared absorbing dye is a phthalocyanine compound, a naphthalocyanine compound, and / or a diimonium compound, The heat ray-shielding pressure-sensitive adhesive composition according to any one of claims 1 to 4 object. (D) The heat ray-shielding pressure-sensitive adhesive composition according to claim 5, wherein the near-infrared absorbing dye is a naphthalocyanine compound represented by the formula (1).

[In the formula (1), M represents a metal atom, a metal oxide, a metal hydroxide, a metal halide, or a hydrogen atom, and X represents a lower alkyl group, a lower alkoxy group, a substituted amino group, a nitro group, a halogen atom. Represents a group, a hydroxy group, a carboxy group, a sulfonic acid group, or a sulfonamide group. A is a divalent bridging group, Y is a sulfonic acid group, a carboxy group, a residue obtained by removing at least one of hydrogen on the nitrogen atom of the primary or secondary amino group, or a nitrogen atom of a heterocyclic ring containing nitrogen Represents a residue excluding at least one of the above hydrogens. m and n are both average values, m and n are each 0 or more and 12 or less, and the sum of m and n is 0 or more and 12 or less. ] The heat ray-shielding pressure-sensitive adhesive according to claim 6, wherein M in the formula (1) is VO, A is an alkylene group having 1 to 3 carbon atoms, and Y is a phthalimide group which may have a substituent. Composition. The heat ray-shielding pressure-sensitive adhesive according to claim 6, wherein M in the formula (1) is Cu, A is an alkylene group having 1 to 3 carbon atoms, and Y is a phthalimide group which may have a substituent. Composition. The heat ray shielding adhesive sheet formed by apply | coating the heat ray shielding adhesive composition as described in any one of Claims 1 thru | or 8.