TW201418393A - A photocurable sealant material composition - Google Patents

Abstract

The present invention provides a photocurable sealant material composition, which comprises: (a) a (meth)acrylate oligomer having one or more functional groups, (b) a photoinitiator, and (c) a plasticizer having a high refractive index, wherein the viscosity of the sealant material composition is not less than 8000cps. The photocurable sealant material composition of the present invention has good transparency, high refractive index and proper flowability and softness, which is easy to be coated and adhered to the elements of touch panels together with liquid optical curable adhesive (aqueous adhesive) such that the formation of an interface between sealants and aqueous adhesives can be obviated. The photocurable sealant material composition of the present invention can be applied to optical products and simplify current manufacturing processes.

Description

Photocurable frame material composition

The invention relates to a photocurable frame material composition, in particular to a photocurable frame material composition which can be used for bonding a display to a touch panel.

With the rapid development of the information industry, electronic products such as mobile phones, personal digital assistants, and notebook computers have become a necessity in people's daily lives. Among these electronic products, the display is an indispensable human-machine communication interface. How to provide a lighter, thinner and better visual product has always been one of the main research and development purposes of the industry. In recent years, the touch panel has been integrated with the display and used in various electronic products, allowing users to directly select various operations on the panel to provide a more convenient and user-friendly operation mode.

As shown in FIG. 1 , the outer surface of the touch panel has an ITO film or ITO glass 11 composed of a polyester film or glass; and a glue layer comprising a liquid optically clear adhesive (LOCA) 12 and A light-cured sealant material composition 13 for attaching the substrate 11 to the display element 14.

This type of sealant has a wide range of applications. Among them, optically clear adhesives have been widely used in displays and touch panels to provide bonding. For example, attaching the touch panel to the display and bonding the ITO film or ITO glass in the touch panel to the outer film or the inner display element are typical application scopes of such a bonding glue. In order not to affect the visual effect, this The frame-like glue must have suitable optical properties such as transparency and refractive index.

As light travels through different media, the difference in refractive index causes light to reflect and affect the light yield. Optical components such as films or glasses typically have a relatively high refractive index, for example, the refractive index of the glass is about 1.52. However, commonly used optically clear adhesives, such as acrylate adhesives, can provide refractive indices generally ranging from 1.40 to 1.45, which still do not meet the needs of the industry. In addition, the optically transparent adhesives used in the industry, such as optical adhesives and lip glues, must be kept flat at all times during the bonding process, otherwise bubbles or wrinkles may occur. In order to improve the process yield, simplify the process steps and meet the requirements of light and thin products, in a new generation process, a liquid optical adhesive with high refractive index is fully integrated, which not only makes the composites look more beautiful. It can also increase the penetration rate. In addition, the full fit can increase the adhesion and tightness of the substrate 11 and the display element 14, and prevent dust and impurities from entering the component more than the conventional adhesive.

However, liquid optical adhesives generally have the disadvantage of being easy to overflow when used. When the adhesive penetrates into the bonding component, it will cause damage to the function of the bonding component, so the fluidity must be properly adjusted to avoid the problem of overflow.

In view of the above, the present invention provides a photocurable frame material composition having a high viscosity and a high refractive index, which will have a significant improvement in the problem of coating the overflow of the liquid optical glue in the process. The frame rubber material composition of the invention has suitable fluidity, softness and refractive index matched with the liquid optical glue, is not only easy to be closely adhered to the liquid optical glue, and avoids the problem of overflowing glue; and the adhesive layer can be achieved in optical properties. Consistency, resulting in sealant and liquid optics There is no interface at the glue junction, which can effectively solve the problems in the prior art.

In order to achieve the above and other objects, the present invention provides a photocurable frame material composition which can be used for the bonding of a display panel and a touch panel, and has a liquid optical adhesive The matching refractive index is not only easy to be in close contact with the liquid optical glue, but also avoids the problem of overflowing of the liquid optical glue.

The present invention provides a photocurable sealant material composition comprising: a) a (meth) acrylate oligomer having one or more functional groups; b) a photoinitiator; and c) a high refraction The plasticizer of the ratio; wherein the viscosity of the sealant material composition is not less than 8000 cps.

The detailed technical features and preferred embodiments of the present invention will be described in the following, which will be understood by those of ordinary skill in the art.

The (meth) acrylate oligomer suitable for the component a) of the present invention has one or more functional groups, preferably a polyfunctional group. The viscosity range of the oligomer suitable for use in the present invention is more than 60,000 cps, preferably 70,000 to 1,200,000 cps, more preferably 80,000 to 1,000,000 cps. If the viscosity is too low, it will affect the viscosity of the whole rubber material, so that it does not have the effect of protecting the components; if the viscosity is too high, it will affect the printing property of the overall rubber material, making it difficult to be used for subsequent construction. The type of the above (meth) acrylate oligomer is, for example, not Limited to: urethane (meth) acrylate, such as aliphatic urethane (meth) acrylate, aromatic polyamine Aromatic urethane (meth) acrylate, aliphatic urethane di (meth) acrylate, aromatic polyamine Aromatic urethane di (meth) acrylate, siliconized urethane (meth) acrylate, aliphatic polyamine amide Aliphatic urethane hexa (meth) acrylate, aromatic urethane hexa (meth) acrylate; epoxy (methyl) Epoxy (meth) acrylate, such as bisphenol-A epoxy di(meth)acrylate, novolac epoxy (meth) Acrylate); polyester (meth)acrylate, such as polyester di(meth)acrylate (meth)acrylate; (meth)acrylate; or a mixture thereof. According to the invention, a polyurethane (meth) acrylate is preferred.

Commercially available (meth) acrylate oligomers suitable for use in the present invention include those manufactured by Eternal Corporation under the trade names 6101-100, 611A-85, 6112-100, 6113, 6114, 6123, 6131, 6144-100. , 6145-100, 6150-100, 6160B-70, 621A-80, 621-100, EX-06, 6315, 6320, 6323-100, 6325-100, 6327-100, 6336-100 or 6361-100; Produced by Sartomer, the trade name is CN9001, CN9002, CN9004, CN9006, CN9014, CN9021, CN963J75, CN966J75, CN973J75, CN962, CN964, CN965, CN940, CN945 or CN990.

According to the present invention, the (meth) acrylate oligomer is used in an amount of from about 40% to about 95%, preferably from about 40% to about 90%, more preferably about 50% by weight based on the total mass of the framing material composition. % to about 85%.

The photoinitiator of component b) used in the photocurable sealant material composition of the present invention is not particularly limited, and is free radicals upon light irradiation, and is initiated by radical polymerization. Responder. The amount of the photoinitiator used can be adjusted according to the type and amount of the monomer/oligomer contained in the sealant material composition of the present invention. Generally, the photoinitiator is present in an amount of from about 0.05% to about 8%, preferably from about 0.1% to about 5%, based on the total weight of the sealant material composition.

Photoinitiators suitable for use in the present invention are, for example but not limited to, benzophenone, benzoin, 2-hydroxy-2-methyl-1-phenylpropan-1-one (2) -hydroxy-2-methyl-1-phenyl-propan-1-one), 2,2-dimethoxy-1,2-diphenylethan-1-one (2,2-dimethoxy-1,2- Diphenylethan-1-one), 1-hydroxy cyclohexyl phenyl ketone, 2,4,6-trimethylbenzhydryldiphenylphosphine oxide (2,4,6- Trimethylbenzoyl diphenyl phosphine oxide), or a mixture thereof. Preferred photoinitiators are benzophenone, 1-hydroxycyclohexyl phenyl ketone or 2,4,6-trimethylbenzimidyl diphenylphosphine oxide.

The high refractive index plasticizer of the component c) used in the present invention must have a refractive index of not less than 1.5, preferably having a refractive index of not less than 1.52. Plasticizer An inert organic material that physically combines with a polymer to produce a homogeneous phase that increases the softness and flexibility of the polymer. The type of plasticizer is well known to those of ordinary skill in the art to which the invention pertains, for example: phthalates, aliphatic dibasic acid esters, phosphate esters, benzene polyesters, lanthanide diesters ( Fluorene-containing diester), alkyl sulfonate, polyol ester or epoxy compound. The plasticizer used in the present invention is preferably selected from the group consisting of phthalic acid esters, fluorene-containing dialkyl benzoates, phosphate esters, and mixtures thereof. The plasticizer included in the photocurable sealant material composition of the present invention can also be used to increase the refractive index of the overall sealant material composition, and the sealant material composition of the present invention has a refractive index of not less than 1.48. Preferably, it has a refractive index of not less than 1.49, more preferably a refractive index of not less than 1.50.

According to an embodiment of the present invention, the plasticizer used in the present invention is an alkyl 4,4'-(9H-fluorene-9,9-diyl)dibenzoate (dialkyl 4,4'-(9H) -fluorene-9,9-diyl)dibenzoate), which has the formula: Wherein R ₁ and R ₂ may be the same or different and are each independently a straight or branched chain C ₁ -C ₁₈ alkyl, C ₃ -C ₈ cycloalkyl, C ₂ -C ₈ alkenyl or C ₆ -C ₁₄ aralkyl, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, decyl, undecyl, propenyl, cyclopropyl, cyclo Butyl, cyclopentyl, cyclohexyl, benzyl.

According to another embodiment of the present invention, the plasticizer used in the present invention is a phosphate having the following formula (2), formula (3) or formula (4):

Wherein R ₃ , R ₄ and R ₅ may be the same or different and each independently is a linear or branched chain C ₁ -C ₁₂ alkyl or phenyl, which may optionally be 1 to 3 straight or branched Chain C _1- C ₄ alkyl substituted; R ₆ is a linear or branched chain C _1- C ₁₂ alkyl, phenyl, which may be 1 to 3 straight or branched C _1- C ₄ alkyl substitution.

According to a preferred embodiment of the present invention, the plasticizer used in the present invention has a phosphate of the formula: Wherein n may be the same or different and each independently is 0, 1, 2 or 3, and R may be the same or different and each independently is a linear or branched chain C ₁ -C ₄ alkyl group, preferably a methyl group.

According to another preferred embodiment of the present invention, the plasticizer used in the present invention has a phosphate of the formula: Wherein n may be the same or different and each independently is 0, 1, 2 or 3, and R may be the same or different and each independently is a linear or branched chain C ₁ -C ₄ alkyl group, preferably a methyl group.

The use of phosphate ester plasticizers can have a flame retardant effect, reducing the possibility of burning materials and reducing fires without the need for additional flame retardants.

The phosphate ester suitable for use in the present invention is preferably triphenyl phosphate (TPP), tricresyl phosphate (TCP), tri(isopropylphenyl)phosphate, phosphoric acid. Cresyl diphenyl phosphate, resorcinol tetraphenyl diphosphate (tetraphenyl resorcinol Diphosphate), tetraphenyl 4,4'-(propane-2,2-diyl)bis(4,1-phenylene)diphosphate or a mixture thereof.

According to the present invention, the plasticizer is used in an amount of from about 4% to about 55%, preferably from about 5% to about 50%, more preferably from about 10% to about 40%, based on the total weight of the sealant material composition. .

The invention provides a photocurable frame material composition with high viscosity and high refractive index. Due to the high viscosity of the sealant material composition of the present invention, the problem of overcoating of the liquid optical glue coating process in the touch display process can be improved, and the sealant material composition of the present invention has appropriate fluidity, softness, and The refractive index close to the liquid optical glue is not only easy to be adhered to the liquid optical glue, but also can achieve the consistency of the optical properties of the bonding layer, so the frame glue and the liquid optical glue do not form an interface after curing, and the excellent Optical effects.

In order to further provide bridging action and reduce the phenomenon of plasticizer precipitation, the sealant material composition of the present invention needs to have a certain viscosity value (not less than 8000 cps) to meet the characteristics required for the sealant, and is the frame sealant material of the present invention. The composition may optionally be added with a component d) having a bridging action and a viscosity adjusting function: a monofunctional group, a polyfunctional monomer or a mixture thereof.

The type of the monomer of the above component d) is, for example but not limited to, a (meth)acrylic monomer, a (meth)acrylate monomer or a mixture thereof, preferably a (meth)acrylate monomer.

The monofunctional (meth) acrylate monomer suitable for use in the present invention may be selected from, but not limited to, methyl methacrylate; MMA), butyl methacrylate, 2-phenoxy ethyl acrylate, ethoxylated 2-phenoxy ethyl acrylate, 2-(2) 2-(2-ethoxyethoxy)ethyl acrylate, cyclic trimethylolpropane formal acrylate, β-carboxyethyl acrylate --carboxyethyl acrylate), 3,3,5-trimethyl cyclohexane acrylate, Ortho-phenyl phenoxy ethyl acrylate, 2-(p-Phenylphenylphenoxyl ethyl acrylate), lauryl methacrylate, isooctyl acrylate, stearic acid Stearyl methacrylate, isodecyl acrylate, isoborny methacrylate, benzyl acrylate, 2-hydroxyethyl methacrylate phosphoric acid 2-hydroxyethyl metharcrylate phosphate, caprolactone A group consisting of caprolactone acrylate, hydroxyethyl acrylate (HEA), 2-hydroxyethyl methacrylate (HEMA), and mixtures thereof.

The polyfunctional (meth) acrylate monomer suitable for use in the present invention may be selected from, but not limited to, 3-hydroxy-2,2-dimethylpropionic acid 3-hydroxy-2,2-dimethyl Hydroxyvalyl hydroxypivalate diacrylate, 1,6-hexanediol diacrylate, ethoxylated 1,6-hexanediol diacrylate (ethoxylated 1,6-hexanediol Diacrylate), dipropylene glycol diacrylate, Tricyclodecane dimethanol diacrylate, ethoxylated dipropylene glycol diacrylate, neopentyl glycol diacrylate (neopentyl glycol diacrylate), propoxylated neopentyl glycol diacrylate, ethoxylated bisphenol-A dimethacrylate, 2-methyl-1,3-propanediol 2-methyl-1,3-propanediol diacrylate, ethoxylated 2-methyl-1,3-propanediol diacrylate, 2-butyl 2-butyl-2-ethyl-1,3-propanediol diacrylate, ethylene glycol dimethacrylate (EGDMA), diethylene glycol Diethylene glycol dimethacrylate, Tris(2-hydroxyethyl)isocyanurate triacrylate, pentaerythritol triacrylate (pentaerythrit) Ol triacrylate), ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate , pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, propofol tetraol tetrapropyl Propoxylated pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, tripropylene glycol dimethacrylate, 1,4-butanediol dimethacrylate (1,4-butanediol) Dimethacrylate), 1,6-hexanediol dimethacrylate, allylated cyclohexyl dimethacrylate, isocyanuric acid dimethacrylate (isocyanurate dimethacrylate), ethoxylated trimethylolpropane trimethacrylate, propoxylated glycerol trimethacrylate, tris(propyleneoxyethyl)isocyanate A group consisting of tris(acryloxyethyl)isocyanurate, trimethylolpropane triacrylate, and mixtures thereof.

Preferably, the monofunctional or polyfunctional monomer usable in the present invention is 2-phenoxy ethyl acrylate, lauryl methacrylate, isodecyl. Isodecyl acrylate, isoborny methacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, ethoxylated trishydroxylate Ethoxylated trimethylol propane trimethacrylate, propoxylated glycerol trimethacrylate, trimethylolpropane triacrylate (trimethylolpropane triacrylate).

Commercially available monofunctional or polyfunctional monomers useful in the present invention include: manufactured by Eternal Corporation under the trade names EM223, EM328, EM2308, EM231, EM219, EM90, EM70, EM235, EM2381, EM2382, EM2383, EM2384, EM2385, EM2386, EM2387, EM331, EM3380, EM241, EM2411, EM242, EM2421 or EM265.

According to the present invention, the monofunctional or polyfunctional monomer or a mixture thereof is used in an amount of from about 0% to about 30%, preferably from about 0% to about 25%, based on the total weight of the sealant material composition, more preferably It is from about 0.1% to about 20%.

The sealant material composition of the present invention may further comprise any additives known to those skilled in the art as needed, component e), such as, but not limited to, a chain transfer agent, a synergist (synergist). , a sensitizer, a coupling agent, a dispersing agent, a wetting agent, a thinning agent, an antifoaming agent, an anti-yellowing agent or a rocking agent.

The sealant material composition of the present invention may also be added with a chain transfer agent as needed; wherein the chain transfer agent is selected from the group consisting of ruthenium tetrapentate (3-mercaptopropionate) (PETAMAP) and 2-mercaptobenzothiazole ( 2-MBT), 2-mercaptobenzoxazole (2-MBO), 4-methyl-4H-1,2,4-triazole-3-thiol (MMT); N-phenylglycine, 1,1-dimethyl-3,5-dione cyclohexane, 2-mercaptobenzimidazole, isoprene tetrahydrazide (mercaptoacetate), 4-ethylguanidinothiophenol, decyl succinic acid, Dodecanethiol, β-mercaptoethanol, carbon tetrabromide, dimethylaniline, ethanethiol, butyl mercaptan, tert-butyl mercaptan, thiophenol and thioglycolate a group of esters and mixtures thereof. The chain transfer agent is present in an amount of from about 0% to about 10%, preferably from about 0.1% to about 6%, more preferably from about 0.5% to about 4%, based on the total weight of the sealant material composition.

The use of the sealant material composition of the present invention, as is well known to those of ordinary skill in the art to which the present invention pertains, is to apply the sealant material composition to a component prior to radiation curing, and other Component fit. For example, the ITO film or ITO glass used as a sensor in the touch panel may be bonded to a glass cover or a cover lens using the sealant material composition of the present invention, or may be used as a sensor. The ITO film or the ITO glass is bonded to another ITO film or ITO glass, or the touch panel is bonded to the display panel module. The present invention also provides a touch display structure comprising: a display panel; a touch panel: and a bonding layer between the display panel and the touch panel for connecting the display panel and the touch The panel, the above-mentioned bonding layer comprises the frame material composition of the present invention.

The present invention further provides a method for manufacturing a touch display, comprising the steps of: providing a display panel; coating the sealant material composition of the present invention around a surface of one of the display panels to form a closed pattern; After the first radiation curing, the frame material composition forms a dish space with the display panel, and fills the liquid optical glue material in the dish space, as shown in FIG. 2, to form a bonding layer; Providing a touch panel cover on the bonding layer; and after performing the second radiation curing, the surface of the display panel is bonded to the touch panel by the bonding layer.

The above display panels are well known to those of ordinary skill in the art to which the present invention pertains, such as, but not limited to, liquid crystal (LCD) panels, organic light emitting diode (OLED) panels, and the like.

The touch panel is well known to those skilled in the art, such as but not limited to a resistive touch panel, an infrared touch panel, a wave touch panel, an optical touch panel, and a capacitive type. Touch panel technology, etc.

According to the present invention, the coating method of the sealant material composition in the above step is, for example but not limited to, knife coating, roller coating, flexographic coating, heat transfer coating. Thermal transfer coat, micro gravure coating, injecting printing, flow coating, dip coating, screen printing , offset printing, spray coating, and curtain coating, or other conventional methods, or a combination of the above. According to a preferred embodiment of the invention, the coating method is dispensing. The pattern formed on the element after the sealant composition is applied is not particularly limited, and is, for example, but not limited to, coated to form a closed pattern. According to a preferred embodiment of the present invention, the pattern is such that the sealant material composition forms a dish-like space with the display panel, such as, but not limited to, forming a square-shaped sealant pattern by dispensing.

The thickness of the bonding layer suitable for use in the present invention is about 50 to 300 μm, preferably 100 to 250 μm. The sealant material composition suitable for use in the present invention has a viscosity of not less than 8000 cps, preferably 8,000 to 120,000 cps, more preferably 9000 to 100,000 cps.

According to the present invention, in the above steps, the sealant material composition of the present invention can be cured by photopolymerization by irradiation with radiation, and provides good adhesion after curing for bonding between components. The above radiation refers to a light source of a certain range of wavelengths, such as ultraviolet light, infrared light, visible light or high energy rays (electron beam), etc., preferably ultraviolet light. The irradiation intensity may be from 500 to 5000 mJ/cm ² (mJ/cm ² ), preferably from 2,000 to 4,000 mJ/cm ² . The intensity of the illumination used for the first and second radiation curing of the present invention may be the same or different.

According to the present invention, the liquid optical glue used in the above step is characterized in that it has a viscosity value of less than 8000 cps, preferably a viscosity value of from 200 cps to 7500 cps, and an optimum viscosity of from 500 cps to 5000 cps. The liquid optical adhesive having the above viscosity range is advantageous for subsequent processing and coating, and the coating method may be selected from the coating method of the sealant material composition of the present invention, preferably by dispensing. The preferred embodiment of the liquid optical gel is selected from the group consisting of ethylenically unsaturated groups, and more preferably the component further comprises the aforementioned plasticizers which are suitable for use in the present invention. In accordance with a preferred embodiment of the present invention, a liquid optical adhesive suitable for use in the present invention has the same refractive index as the sealant material composition of the present invention.

The sealant material composition of the present invention comprises a plasticizer having a refractive index of not less than 1.5, and the bridging material composition of the present invention has a high bridging density after curing, The plasticizer is not easily precipitated, does not cause environmental problems, and can have good light transmittance and high refractive index after curing the frame material composition. The frame sealant composition of the present invention has a higher overall refractive index after curing than the sealant composition without the plasticizer. The frame rubber material composition of the invention has good softness and can be used for optical electronic products, especially in the bonding of the display panel and the touch panel, and the liquid optical glue material can provide a buffering effect and enhance the visual beauty of the screen.

Taking FIG. 2 as an example, the sealant material composition 24 of the present invention has suitable fluidity, and is favorable for coating and laminating the touch panel 22 (having a protective cover 21 on the 22), and has good workability. Therefore, it can replace the optical tape and is applied to related fields such as the bonding of the touch panel and the display panel, thereby simplifying the process and improving the yield. In addition, after the first radiation curing of the sealant material composition 24, the function of protecting the display element is ensured, and the function of the original component can be ensured. It is effectively avoided that the liquid optical adhesive 23 or the sealant material composition 24 itself erodes into the slit 26 of the display member 25, damaging the display member.

The following examples are intended to illustrate the invention and are not intended to limit the scope of the invention. Modifications and variations that may be readily made by those skilled in the art are included within the scope of the disclosure of the present disclosure and the scope of the appended claims.

Examples 1 to 10 and Comparative Example 1

The glues of the photocurable sealant material compositions of Examples 1 to 10 and Comparative Example 1 were prepared in the manner described below, and the compositions are as listed in Table 1.

First, the components were mixed in the weights (g) listed in Table 1, and stirred at room temperature and in a dark room until completely mixed uniformly to form a photocurable sealant material composition.

(a): Polyurethane acrylate oligomer (produced by Changxing Co., Ltd., EX-06) (b1): Monofunctional monomer (tetrahydrofurfuryl acrylate; produced by Changxing Co., Ltd., EM214) B2): polyfunctional monomer (ethoxylated bisphenol A diacrylate; produced by Changxing Co., Ltd., EM2261) (c): photoinitiator (1-hydroxycyclohexyl phenyl ketone; produced by BASF, Irgacure 184 (d1): plasticizer (tetraphenyl 4,4'-(propane-2,2-diyl)bis(4,1-phenylene)diphosphate)) (d2): Plasticizer (Tetraphenyl resorcinol bis (diphenylphosphate) (d3): plasticizer (Tricresyl phosphate (TCP)) (e): chain transfer agent (C12 thiol) The above (a)-(g) are all >99% pure.

Comparative example 2

Commercially available optical glue: DBA2000, DuPont.

testing method:

Viscosity : The viscosity of the glue was tested at 25 ° C using a Brookfield LV viscometer.

Refractive index : The refractive index of the glue was measured using a DR-A1 A-Line inflection meter (ATAGO). Subsequently, the glue was cured by ultraviolet light at an irradiation intensity of 3000 mJ/cm ² , and the refractive index after curing was measured.

Penetration : The penetration of the sealant after curing was measured using an NDH 5000W haze meter (Nippon Denshoku Co., Ltd.).

Protection test slot (leakage test): In the first embodiment each dispensing the sealant in the sealing material composition of the gap between the two glass thickness of 0.5 mm, the slot length of 2 cm and a gap size of 0.5 mm, followed by using 0.1 g of red A mixture of 0.4 g of a dye (Taiwan Super) and 0.4 g of a monomer (tetrahydrofurfuryl acrylate; manufactured by Changxing Co., Ltd., EM214) was dropped on the sealant material composition and allowed to stand for 1 hour.

If the monomer or sealant material composition with red dye between the gaps is filled, it is unqualified, indicated by X. If no ink is infiltrated or the frameless material composition is filled, it is qualified, indicated by ○.

Test Results:

The test results obtained above are recorded in Table 2.

As can be seen from Table 2, the sealant material composition of the present invention has a transmittance of more than 99% after curing; and compared to a sealant material composition containing no plasticizer (Comparative Example 1) and a commercially available optical glue (Comparative Example 2), the sealant material composition of the present invention has a relatively high refractive index and can effectively increase the refractive index after curing to 1.50 or higher. After the leakage test of the sealant material composition of Comparative Example 2, it was observed that the sealant material composition and the monomer having the red dye were present in the test glass gap. Therefore, the sealant material composition suitable for use in the present invention has a viscosity value (greater than 8000 cps) in order to form a sealant as a container capable of holding a liquid optical adhesive. In addition, the sealant material composition of the present invention can reduce the hardness of the prepared coating layer by providing a plasticizer, and provides better cushioning property, and avoids water ripple caused by stress of the touch panel. Good visual effect.

11‧‧‧Protective cover/ITO film or ITO glass

12‧‧‧Liquid optical glue

13‧‧‧Photocurable frame material composition

14‧‧‧ITO film or ITO glass/display component

21‧‧‧Protection cover

22‧‧‧Touch components

23‧‧‧Liquid optical glue

24‧‧‧Frame material composition

25‧‧‧Display components

26‧‧‧Show gaps in components

Figure 1 is a schematic view showing the application of a liquid optical glue to a conforming layer having a frame structure.

11‧‧‧Protective cover/ITO film or ITO glass

12‧‧‧Liquid optical glue

13‧‧‧Photocurable frame material composition

14‧‧‧ITO film or ITO glass/display component

Claims (10)

A photocurable sealant material composition comprising: a) a (meth) acrylate oligomer having one or more functional groups; b) a photoinitiator; and c) a high refractive index a plasticizer; wherein the sealant material composition has a viscosity value of not less than 8000 cps. The sealant material composition of claim 1, wherein the (meth) acrylate oligomer is selected from the group consisting of urethane (meth) acrylate, epoxy (meth) acrylate, and polyester (meth) acrylate. A group of esters, (meth) acrylate oligomers, and mixtures thereof. The sealant material composition of claim 1, wherein the (meth) acrylate oligomer is used in an amount of from about 40% to about 95% by total weight of the composition. The sealant material composition of claim 1, wherein the photoinitiator is selected from the group consisting of benzophenone, benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2 , 2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethylbenzhydryldiphenylphosphine oxide and a group of mixtures The sealant material composition of claim 1 wherein the photoinitiator is present in an amount of from about 0.05% to about 8%, based on the total weight of the composition. The sealant material composition of claim 1, wherein the plasticizer has an alkyl phthalate of the following formula (1); a phosphate of (2), (3) or (4): Wherein R ₁ and R ₂ may be the same or different and are each independently a straight or branched chain C ₁ -C ₁₈ alkyl, C ₃ -C ₈ cycloalkyl, C ₂ -C ₈ alkenyl or C ₆ -C _{a 14} aralkyl group, wherein R ₃ , R ₄ and R ₅ may be the same or different and each independently is a linear or branched chain C ₁ -C ₁₂ alkyl or phenyl group, and the phenyl group may be subjected to 1 to 3 Straight or branched chain C _1- C ₄ alkyl substituted; R ₆ is a linear or branched chain C _1- C ₁₂ alkyl or phenyl, which may be 1 to 3 linear or branched chain C _1- C ₄ alkyl. The sealant material composition of claim 1, wherein the plasticizer has not less than 1.5 refractive index. The sealant material composition of claim 1 wherein the plasticizer is present in an amount of from about 4% to about 55% by weight based on the total weight of the composition. The sealant material composition of claim 1, wherein the sealant material composition has a refractive index of not less than 1.48. The sealant material composition of any one of claims 1 to 9, which is used in the process of a touch display.