Photosensitive resin composition for packaging optoelectronic component and use method thereof

Abstract

The invention belongs to the field of organic thin film packaging materials, and particularly discloses a photosensitive resin composition for packaging a photoelectron component and a use method of the photosensitive resin composition, and the photosensitive resin composition comprises the following components in parts by mass: 20-50 parts of an ultraviolet curable monomer, 2-8 parts of a photo-crosslinking initiator and 5-30 parts of functional dispersion liquid. Wherein the ultraviolet light curable monomer is formed by mixing (methyl) acrylate containing a long carbon chain and a bridged ring light curable monomer according to a specific mass ratio; the functional dispersion liquid comprises a monofunctional group reaction monomer and hollow microspheres, and the surfaces of the hollow microspheres are connected with organic modification groups. The photosensitive resin composition is excellent in comprehensive performance, the viscosity and surface tension of the photosensitive resin composition meet the range of ink-jet printing requirements, the photosensitive resin composition has high curing rate, light transmittance and refractive index, especially the dielectric constant can be controlled to be 2 or below, and the photosensitive resin composition has excellent mechanical property and water and oxygen isolation capacity and provides material support for packaging of related electronic components.

Description

Technical Field

[0001] The invention belongs to the technical field of organic thin films, and in particular relates to a photosensitive resin composition for encapsulating optoelectronic components and a use method thereof. Background Art

[0002] As semiconductor technology continues to make progress, Organic Light-Emitting Diode (OLED), a device that uses a multi-layer organic thin film structure to generate electroluminescence, has been widely used in the field of flexible displays. It has a series of significant advantages such as easy production, low driving voltage, light weight and portability, wide color gamut, excellent brightness, low power consumption, fast response, high clarity, excellent flexibility and high luminous efficiency. It is one of the display technologies with the most development potential at present and can greatly meet consumers' new demands for display technology.

[0003] However, the current OLED technology still has some problems, such as short life, insufficient brightness and poor reliability. These problems mainly stem from the fact that OLED devices are susceptible to the adverse effects of external water, oxygen and outgassing, which causes oxidation of the organic layer and electrode layer, resulting in bad points, and ultimately leads to a significant decrease in device performance and a serious shortening of life. At present, in order to prevent organic molecular materials from being damaged by water and oxygen, the commonly used method is to prepare the organic encapsulation layer with the help of inkjet printing thin film encapsulation composition, so as to achieve complete isolation of organic molecular materials from the air and build a strict encapsulation system. In this process, on the one hand, the thin film encapsulation composition is required to have good spreadability to avoid negatively affecting the effect of inkjet printing; on the other hand, the organic encapsulation layer needs to have a low dielectric constant and dielectric loss, so as to effectively reduce the signal-to-noise ratio of the device and reduce signal delay. Therefore, the development of thin film encapsulation compositions with low dielectric constants has become the key to the field of flexible OLED encapsulation technology.

[0004] At present, the commonly used method includes adding substances with low dielectric constant characteristics, such as fluorinated monomers, but generally large-volume fluorinated monomers are often less reactive, which will not only cause the thermal and mechanical properties of the material to be lost during use, but also accompanied by higher costs. In addition, there is another method of introducing air micropores into the resin, using the low dielectric constant characteristics of air to reduce the average dielectric constant of the material, but this method has obvious disadvantages. The introduction of air micropores will cause the stability of the film encapsulation material to deteriorate, and it is very easy to cause other problems such as pore blocking or phase separation during inkjet printing, so this type of material is currently not applicable to inkjet printing technology. In addition, the introduction of excessive cavities will also cause serious obstacles to the mechanical properties and water-oxygen barrier properties of the film material. For example, a low dielectric constant hollow carbon ball / epoxy resin composite material disclosed in China Announcement No. CN103756253B, although it has the advantages of light weight, low dielectric constant, good thermal conductivity, dimensional stability and chemical stability, but its surface tension and viscosity cannot meet the requirements of the inkjet printing process, and the mechanical properties and water-oxygen barrier properties are also difficult to be effectively guaranteed.

[0005] In view of this, this invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a photosensitive resin composition for optoelectronic component packaging and a method of using the same, which are mainly used to solve a series of problems existing in existing thin film packaging materials in practical application scenarios, specifically manifested in high dielectric constants, frequent pore blocking and phase separation during inkjet printing, and poor mechanical properties and water and oxygen barrier properties.

[0007] The purpose of the present invention is to be solved by the following technical solutions: In a first aspect, the present invention provides a photosensitive resin composition for encapsulating optoelectronic components, comprising the following raw materials in parts by mass: 20 to 50 parts of an ultraviolet light-curable monomer, 2 to 8 parts of a photocrosslinking initiator, and 5 to 30 parts of a functional dispersion; Wherein, the functional dispersion includes monofunctional reactive monomers and hollow microspheres.

[0008] Note: The hollow microspheres of the present invention refer to spherical structures with a cavity inside.

[0009] Preferably, the formulation of the photosensitive resin composition for encapsulating optoelectronic components is: 25 to 45 parts of UV-curable monomer, 2 to 5 parts of photocrosslinking initiator and 14 to 21 parts of functional dispersion.

[0010] Furthermore, the mass ratio of the monofunctional reaction monomer to the hollow microspheres is (2-3):1.

[0011] Preferably, the mass ratio of the monofunctional reactive monomer to the hollow microspheres is (2.4-2.6):1.

[0012] Furthermore, the monofunctional reactive monomer is an acrylate monomer, and has a viscosity of 2 cps to 10 cps.

[0013] Specifically, the acrylic acid ester monomer includes any one of lauric acid acrylate, isodecyl acrylate, isooctyl acrylate, isononyl acrylate, lauric acid methacrylate and 2-ethylhexyl methacrylate.

[0014] Furthermore, the surface of the hollow microsphere is connected with an organic modification group, and the organic modification group is an acrylate group or a methacrylate group; The hollow microspheres include hollow silicon dioxide microspheres; The particle size of the hollow microspheres is 10nm to 100nm, preferably 20nm to 50nm; The wall thickness of the hollow microspheres is 2nm to 6nm.

[0015] Furthermore, the monofunctional reactive monomer and the surface-modified hollow microspheres are mixed in the above mass ratio to obtain a functional dispersion.

[0016] Specifically, the method for preparing the surface-modified hollow microspheres of the present invention comprises the following steps: Step 1, firstly mix hexadecyltrimethylammonium bromide (surfactant) and tetraethyl orthosilicate in a molar ratio of (0.1-0.5):1, then add into an ammonia solution, stir and dissolve, then react the mixed solution at a constant temperature of 30°C-80°C for 5h-10h, centrifuge the obtained reaction product, remove the supernatant and dry the residue to obtain a white powder, finally calcine the obtained white powder at a temperature of 600°C-650°C for 0.5h-1h to remove the surfactant, thereby obtaining mesoporous spherical silica microspheres, i.e., obtaining hollow microspheres; Step 2: adding an organic substance for treating the surface of the hollow microspheres obtained in step 1, so that the surface of the hollow microspheres is connected with an organic modification group, wherein the organic modification group is an acrylate group or a methacrylate group.

[0017] Wherein, in step 2, the mass ratio of the hollow microspheres to the organic substance is (1-2): (1-2); the organic substance includes any one of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane or 3-(isomethacryloyloxy)propyltrimethoxysilane.

[0018] It should be noted that the present invention firstly mixes the hollow microspheres (with modified groups connected to the surface) and the monofunctional reactive monomers in proportion to obtain a functional dispersion, and then adds the dispersion into the system to obtain a photosensitive resin composition. Compared with directly adding the hollow microspheres into the system, the present invention has the following effects: (1) Interaction between the modifying group and the monofunctional reactive monomer: There is a chemical affinity between the modifying group (acrylate or methacrylate) on the surface of the hollow microspheres and the monofunctional reactive monomer (acrylate monomer). This affinity enables the hollow microspheres to form a stable mixture with the acrylate monomer, thereby improving the solubility of the hollow microspheres in the UV-curable monomer.

[0019] (2) Regulating the viscosity of the system: The interaction between the modified groups on the surface of the hollow microspheres and the acrylic monomers reduces the viscosity of the system. At the same time, the acrylic monomers have a lower viscosity and can help regulate the distribution of the hollow microspheres in the system, thereby improving the fluidity of the mixture and effectively reducing the overall viscosity of the system. When the hollow microspheres are mixed with acrylic monomers, they can fill the gaps between the monomers, further reducing the viscosity of the system.

[0020] (3) Preventing the aggregation of nano-scale hollow microspheres: Hollow microspheres usually have low solubility, especially nano-scale hollow microspheres, which have high surface energy and are prone to aggregation, thus affecting the performance of the photosensitive resin composition. Monofunctional acrylate monomers have strong surface activity. They can be adsorbed on the surface of hollow microspheres and interact with the surface of hollow microspheres through physical adsorption or chemical reaction. This surface modification reduces the surface energy of hollow microspheres, thereby reducing their aggregation tendency.

[0021] (4) Enhance system stability: Photocurable monomers usually have low polarity and high viscosity. Directly adding hollow microspheres may cause microsphere aggregation. By first mixing with acrylate monomers, the hollow microspheres are well dispersed in the acrylate monomers with lower viscosity. When the UV-curable monomers are added, the hollow microspheres are already in a uniformly dispersed state and are not easy to aggregate, thereby improving the uniformity and stability of the mixed system.

[0022] In addition, adding hollow microspheres can reduce the density of the material, but adding too much will reduce the mechanical properties and barrier properties of the material. In order to overcome this problem, the present invention preferably uses hollow microspheres with a particle size of 20nm to 50nm and a wall thickness of 2nm to 6nm, and the amount of functional dispersion added is 5 to 30 parts. At the same time, by properly adjusting the ratio of monofunctional reactive monomers to ultraviolet light curable monomers, it is possible to achieve a balance between tensile strength and elongation at break, and improve the barrier properties of the film, thereby effectively blocking the penetration of water and oxygen.

[0023] Furthermore, the UV-curable monomer is a mixture of a (meth)acrylate containing a long carbon chain and a bridged ring photocurable monomer.

[0024] Furthermore, the mass ratio of the monofunctional reactive monomer, the (meth)acrylate containing a long carbon chain and the bridged ring photocurable monomer is (10-15): (15-30): (10-15).

[0025] Among them, (meth)acrylates containing long carbon chains can give the material flexibility and fluidity, which helps to achieve high-quality printing effects, and can effectively reduce the surface tension of the material, thereby improving the fluidity of the material. At the same time, (meth)acrylates containing long carbon chains can produce cross-linking reactions with bridge-ring monomers, thereby building a three-dimensional network structure and strengthening the strength of the material. In addition, the introduction of bridge-ring photocurable monomers can help increase the cross-linking density, enhance the barrier properties of the material, and reduce the water and oxygen permeability. The functional dispersion works synergistically with (meth)acrylates containing long carbon chains and bridge-ring photocurable monomers, which can not only balance the cross-linking density, flexibility and photocuring performance of the material, but also effectively reduce the dielectric constant and dielectric loss of the material, and improve the transmittance of the cured film.

[0026] Further, the (meth)acrylate containing a long carbon chain includes one or more of 1,6-hexanediol diacrylate, 2-methyl-2-acrylate-1,10-decanediol, 2-methyl-2-acrylate-1,9-nonanediol dimethacrylate, 1,5-pentanediol dimethacrylate, 1,11-undecanediol dimethacrylate, 1,12-dodecanediol di(meth)acrylate, 1,13-tridecanediol dimethacrylate, 1,14-tetradecanediol di(meth)acrylate or 1,18-octadecanediol dimethacrylate; The bridged ring photocurable monomer includes a bridged ring diacrylate monomer containing six to twenty-five carbon atoms, specifically one or more of dicyclopentenyl acrylate, isobornyl acrylate, cyclohexyl methacrylate, isobornyl methacrylate, dicyclopentyl methacrylate, tricyclodecane dimethanol diacrylate, tricyclodecane dimethanol dimethacrylate, dicyclopentenyl ethoxylated acrylate, dicyclopentenyl ethoxylated methacrylate, isobornyl (meth)acrylate or dicyclopentenyl (meth)acrylate.

[0027] Among them, the glass transition temperature (Tg) of the bridge ring photocurable monomer is 80°C to 170°C.

[0028] Further, the photocrosslinking initiator includes one or more of TPO, TEPO, 1173, 184, 819, 4-methoxybenzaldehyde, 4,4'-bis(dimethylamino)benzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, bisbenzoylphenylphosphine oxide or benzoyldiphenylphosphine oxide.

[0029] After actual testing, the photosensitive resin composition formed by the present invention has a surface tension of 27 dyne / cm to 30 dyne / cm at a temperature of 25±5° C., a viscosity of 21 cps to 24 cps, is suitable for inkjet printing, and has a dielectric constant of only 1.9 to 22.

[0030] In a second aspect, the present invention provides a method for using the above-mentioned photosensitive resin composition for encapsulating optoelectronic components, and the specific steps are as follows: Step 1: firstly attach the photosensitive resin composition to the surface of the optoelectronic component to be packaged by spin coating, doctor blade coating, screen printing or inkjet printing; Step 2: Next, the photosensitive resin composition is irradiated with ultraviolet light having a wavelength between 250 nm and 400 nm for 30 s to 600 s, and finally the photosensitive resin composition is cured to form an organic film having a thickness of 5 μm to 50 μm.

[0031] Furthermore, the optoelectronic components include light emitting diodes, photosensors, photovoltaic devices, etc.

[0032] Taking a flexible OLED device as an example, it includes an ITO substrate, an organic light-emitting diode, an inorganic packaging film layer and an organic packaging film layer stacked in sequence.

[0033] Among them, the organic encapsulation film layer uses the photosensitive resin composition of the present invention and is formed by inkjet printing; the inorganic encapsulation film layer is a film layer of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, indium oxide, silicon nitride, etc., which is formed by chemical vapor deposition or atomic deposition.

[0034] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention premixes hollow microspheres with modified groups on the surface with acrylate monomers, and then adds ultraviolet light-curable monomers and photo-crosslinking initiators to prepare a photosensitive resin composition, which can significantly improve the solubility of hollow microspheres, adjust the viscosity of the system, and effectively curb the aggregation of nano-scale hollow microspheres. That is, this premixing mechanism not only optimizes the processing performance of the system, but also fundamentally strengthens the stability and comprehensive performance of the photosensitive resin composition, laying a solid foundation for its reliable operation in practical applications.

[0035] 2. The functional dispersion of the present invention is added with hollow microspheres filled with gas. When the hollow microspheres are evenly dispersed in the system, a multiphase system containing air is constructed. With the low dielectric properties of the gas, the polarization ability of the composite material under the action of the electric field is reduced, thereby significantly reducing the overall dielectric constant of the composite material. At the same time, the outer shell of the hollow microspheres can play a shielding role, effectively hindering the transmission of charge in the medium, and its presence reduces the density of polar molecules in the resin, further reducing the polarization effect, so that the dielectric constant can be further reduced, meeting the stringent requirements of the packaging material for low dielectric properties.

[0036] 3. The present invention adjusts the mass ratio of the monofunctional reactive monomer, the (meth)acrylate containing a long carbon chain and the bridge ring photocurable monomer within the range of (10-15): (15-30): (10-15), and controls the addition amount of the functional dispersion, thereby achieving the following effects: First, in terms of inkjet printing performance, the surface tension and viscosity can be adjusted to a suitable range to improve the printing quality; second, in terms of material performance, the toughness of the material can be effectively improved, the brittleness can be significantly reduced, and the durability and reliability of the film can be greatly enhanced, so that it can still maintain excellent performance in complex environments; third, in terms of barrier performance, it can achieve efficient blocking of water and oxygen penetration, provide a long-lasting and stable protective barrier for electronic components, and extend the service life of electronic components. DETAILED DESCRIPTION

[0037] Here, exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples consistent with some aspects of the present invention described in detail in the appended claims.

[0038] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with relevant experiments.

[0039] Preparation Example 1 The functional dispersion in the embodiment of the present invention uses surface-modified hollow microspheres, and the preparation process is as follows: 1) Hexadecyltrimethylammonium bromide and tetraethyl orthosilicate were mixed in a molar ratio of 0.3:1, and then added to an ammonia solution, stirred and dissolved, and then the mixed solution was reacted at a constant temperature of 60°C for 6 hours, the obtained reaction product was centrifuged, the supernatant was removed and the residue was dried to obtain a white powder, and finally the obtained white powder was calcined at 600°C for 1 hour to remove the surfactant, thereby obtaining mesoporous spherical silica microspheres, that is, hollow microspheres with a particle size of 50nm and a wall thickness of 3nm; 2) 3-(methacryloyloxy)propyltrimethoxysilane was added to the above hollow microspheres at a mass ratio of 1:1 for surface treatment, thereby obtaining surface-modified hollow microspheres with a particle size of 50 nm (in the present invention, the particle size of the hollow microspheres refers to the average particle size).

[0040] Preparation Example 2 The functional dispersion in the embodiment of the present invention uses surface-modified hollow microspheres, and the preparation process is as follows: 1) Hexadecyltrimethylammonium bromide and tetraethyl orthosilicate were mixed in a molar ratio of 0.3:1, and then added to an ammonia solution, stirred and dissolved, and then the mixed solution was reacted at a constant temperature of 60°C for 6 hours, the obtained reaction product was centrifuged, the supernatant was removed and the residue was dried to obtain a white powder, and finally the obtained white powder was calcined at 600°C for 1 hour to remove the surfactant, thereby obtaining mesoporous spherical silica microspheres, that is, hollow microspheres with a particle size of 50nm and a wall thickness of 3nm; 2) 3-(acryloyloxy)propyltrimethoxysilane was added to the above hollow microspheres at a mass ratio of 1:2 for surface treatment, thereby obtaining surface-modified hollow microspheres with a particle size of 50 nm.

[0041] Preparation Example 3 The functional dispersion in the embodiment of the present invention uses surface-modified hollow microspheres, and the preparation process is as follows: 1) Hexadecyltrimethylammonium bromide and tetraethyl orthosilicate were mixed in a molar ratio of 0.3:1, and then added to an ammonia solution, stirred and dissolved, and then the mixed solution was reacted at a constant temperature of 60°C for 6 hours, the obtained reaction product was centrifuged, the supernatant was removed and the residue was dried to obtain a white powder, and finally the obtained white powder was calcined at 600°C for 1 hour to remove the surfactant, thereby obtaining mesoporous spherical silica microspheres, that is, hollow microspheres with a particle size of 50nm and a wall thickness of 3nm; 2) 3-(isobutyleneoxy)propyltrimethoxysilane was added to the above hollow microspheres at a mass ratio of 2:1 for surface treatment, thereby obtaining surface-modified hollow microspheres with a particle size of 50 nm.

[0042] Preparation Example 4 The functional dispersion in Comparative Example 3 of the present invention uses surface-modified hollow microspheres, and the preparation process is as follows: 1) Hexadecyltrimethylammonium bromide and tetraethyl orthosilicate were first mixed at a molar ratio of 0.2:3, and then added to an ammonia solution, stirred and dissolved, and then the mixed solution was reacted at a constant temperature of 60°C for 6 hours, the obtained reaction product was centrifuged, the supernatant was removed, and the residue was dried to obtain a white powder, and finally the obtained white powder was calcined at 600°C for 1 hour to remove the surfactant, thereby obtaining mesoporous spherical silica microspheres, that is, hollow microspheres with a particle size of 200 nm; 2) 3-(methacryloyloxy)propyltrimethoxysilane was added to the above hollow microspheres at a mass ratio of 1:1 for surface treatment, thereby obtaining surface-modified hollow microspheres with a particle size of 200 nm. Example 1

[0043] The photosensitive resin composition provided in the embodiment of the present invention comprises, by weight, 14.5 parts of a functional dispersion, 25 parts of an ultraviolet light-curable monomer, and 5 parts of a photocrosslinking initiator. The mass ratio of the monofunctional reaction monomer to the hollow microspheres in the functional dispersion is 10:4.5; the ultraviolet light-curable monomer is a mixture, comprising 15 parts of a (meth)acrylate containing a long carbon chain and 10 parts of a bridged ring photocurable monomer.

[0044] Specifically, the monofunctional reactive monomer is lauric acid acrylate, and the hollow microspheres are prepared according to Preparation Example 1 to finally obtain surface-modified hollow microspheres with a particle size of 50 nm.

[0045] The (meth)acrylate containing a long carbon chain is selected from 1,6-hexanediol diacrylate.

[0046] The bridge ring photocurable monomer is isobornyl acrylate.

[0047] TPO was selected as the photocrosslinking initiator.

[0048] When preparing the photosensitive resin composition, at room temperature and in a light-proof environment, 10 parts of lauric acid acrylate and 4.5 parts of the surface-modified hollow microspheres with a particle size of 50 nm finally obtained in Preparation Example 1 are pre-mixed to obtain 14.5 parts of a functional dispersion liquid, and then 15 parts of 1,6-hexanediol diacrylate, 10 parts of isobornyl acrylate and 5 parts of TPO are added thereto, and the mixture is mixed and stirred until the initiator is completely dissolved, and the photosensitive resin composition is obtained after standing. Example 2

[0049] The photosensitive resin composition provided in the embodiment of the present invention comprises, by weight, 14.3 parts of a functional dispersion, 25 parts of an ultraviolet light-curable monomer, and 2 parts of a photocrosslinking initiator. The mass ratio of the monofunctional reaction monomer to the hollow microspheres in the functional dispersion is 10:4.3; the ultraviolet light-curable monomer is a mixture, comprising 15 parts of a (meth)acrylate containing a long carbon chain and 10 parts of a bridged ring photocurable monomer.

[0050] Specifically, the monofunctional reactive monomer is isooctyl acrylate, and the hollow microspheres are prepared according to Preparation Example 1 to finally obtain surface-modified hollow microspheres with a particle size of 50 nm.

[0051] The (meth)acrylate containing a long carbon chain is selected from 1,6-hexanediol diacrylate.

[0052] The bridge ring photocurable monomer is isobornyl methacrylate.

[0053] TPO was selected as the photocrosslinking initiator.

[0054] When preparing the photosensitive resin composition, at room temperature and in a light-proof environment, 10 parts of isooctyl acrylate and 4.3 parts of the surface-modified hollow microspheres with a particle size of 50 nm finally obtained in Preparation Example 1 are pre-mixed to obtain 14.3 parts of a functional dispersion, and then 15 parts of 1,6-hexanediol diacrylate, 10 parts of isobornyl acrylate and 5 parts of TPO are added thereto, and the mixture is stirred until the initiator is completely dissolved, and the photosensitive resin composition is obtained after standing. Example 3

[0055] The photosensitive resin composition provided in the embodiment of the present invention comprises, by weight, 14 parts of a functional dispersion, 30 parts of an ultraviolet light-curable monomer, and 3 parts of a photocrosslinking initiator. The mass ratio of the monofunctional reaction monomer to the hollow microspheres in the functional dispersion is 10:4; the ultraviolet light-curable monomer is a mixture, comprising 20 parts of a (meth)acrylate containing a long carbon chain and 10 parts of a bridged ring photocurable monomer.

[0056] Specifically, the monofunctional reactive monomer is isononyl acrylate, and the hollow microspheres are prepared according to Preparation Example 2 to finally obtain surface-modified hollow microspheres with a particle size of 50 nm.

[0057] The (meth)acrylate containing a long carbon chain is selected from 1,11-undecanediol dimethacrylate.

[0058] The bridge ring photocurable monomer is dicyclopentenyl ethoxylated acrylate.

[0059] The photocrosslinking initiator is 4-methoxybenzaldehyde.

[0060] When preparing the photosensitive resin composition, at room temperature and in a light-proof environment, 10 parts of isononyl acrylate and 4 parts of the surface-modified hollow microspheres with a particle size of 50 nm finally obtained in Preparation Example 2 are pre-mixed to obtain 14 parts of a functional dispersion, and then 20 parts of 1,11-undecanediol dimethacrylate, 10 parts of dicyclopentenyl ethoxylated acrylate and 3 parts of 4-methoxybenzaldehyde are added thereto, and the mixture is stirred until the initiator is completely dissolved, and the photosensitive resin composition is obtained after standing. Example 4

[0061] The photosensitive resin composition provided in the embodiment of the present invention comprises, by weight, 18 parts of a functional dispersion, 40 parts of an ultraviolet light-curable monomer, and 5 parts of a photocrosslinking initiator. The mass ratio of the monofunctional reaction monomer to the hollow microspheres in the functional dispersion is 13:5; the ultraviolet light-curable monomer is a mixture, comprising 25 parts of a (meth)acrylate containing a long carbon chain and 15 parts of a bridged ring photocurable monomer.

[0062] Specifically, the monofunctional reactive monomer is 2-ethylhexyl methacrylate, and the hollow microspheres are prepared according to Preparation Example 2 to finally obtain surface-modified hollow microspheres with a particle size of 50 nm.

[0063] The (meth)acrylate containing a long carbon chain is selected from 1,11-undecanediol dimethacrylate.

[0064] The bridged ring photocurable monomer is dicyclopentenyl acrylate.

[0065] The photo cross-linking initiator selected is 819.

[0066] When preparing the photosensitive resin composition, at room temperature and in a light-proof environment, 13 parts of 2-ethylhexyl methacrylate and 5 parts of the surface-modified hollow microspheres with a particle size of 50 nm obtained in Preparation Example 2 were pre-mixed to obtain 18 parts of a functional dispersion, and then 25 parts of 1,11-undecanediol dimethacrylate, 15 parts of dicyclopentenyl acrylate and 5 parts of TPO were added thereto, and the mixture was stirred until the initiator was completely dissolved, and the photosensitive resin composition was obtained after standing. Example 5

[0067] The photosensitive resin composition provided in the embodiment of the present invention comprises, by weight, 21 parts of a functional dispersion, 45 parts of an ultraviolet light-curable monomer, and 5 parts of a photocrosslinking initiator. The mass ratio of the monofunctional reaction monomer to the hollow microspheres in the functional dispersion is 15:6; the ultraviolet light-curable monomer is a mixture, comprising 30 parts of a (meth)acrylate containing a long carbon chain and 15 parts of a bridged ring photocurable monomer.

[0068] Specifically, the monofunctional reactive monomer is isodecyl acrylate, and the hollow microspheres are prepared according to Preparation Example 3 to finally obtain surface-modified hollow microspheres with a particle size of 50 nm.

[0069] The (meth)acrylate containing a long carbon chain is selected from 1,18-octadecanediyl dimethacrylate.

[0070] The bridge ring photocurable monomer is dicyclopentenyl (meth)acrylate.

[0071] The photo cross-linking initiator selected was 819.

[0072] When preparing the photosensitive resin composition, at room temperature and in a light-proof environment, 15 parts of isodecyl acrylate and 6 parts of the surface-modified hollow microspheres with a particle size of 50 nm finally obtained in Preparation Example 3 were pre-mixed to obtain 21 parts of a functional dispersion, and then 30 parts of 1,18-octadecanediyl dimethacrylate, 15 parts of (meth)acrylate dicyclopentenyl ester and 5 parts of 819 were added thereto, and the mixture was stirred until the initiator was completely dissolved, and the photosensitive resin composition was obtained after standing.

[0073] Comparative Example 1 The only difference between this comparative example and Example 1 is that no functional dispersion liquid is added to the photosensitive resin composition of this comparative example.

[0074] Comparative Example 2 The only difference between this comparative example and Example 1 is that no monofunctional reactive monomer is added to the functional dispersion liquid of this comparative example.

[0075] Comparative Example 3 The only difference between this comparative example and Example 1 is that the particle size of the hollow microspheres added to the functional dispersion of this comparative example adopts the particle size of Preparation Example 4 to finally obtain surface-modified hollow microspheres with a particle size of 200 nm, that is, the particle size of the hollow microspheres in the functional dispersion of this comparative example is not in the range of 10 nm to 100 nm.

[0076] Comparative Example 4 The only difference between this comparative example and Example 1 is that the amount of the functional dispersion added in this comparative example is 40 parts, that is, the amount of the functional dispersion added in the photosensitive resin composition of this comparative example is too much.

[0077] Comparative Example 5 The only difference between this comparative example and Example 1 is that the mass ratio of the monofunctional reactive monomer, the long carbon chain-containing (meth)acrylate and the bridge ring photocurable monomer in the photosensitive resin composition of this comparative example is 20:10:20, that is, it is not within the ratio range of (10-15): (15-30): (10-15).

[0078] Comparative Example 6 The only difference between this comparative example and Example 1 is that in this comparative example, 15 parts of butyl methacrylate and 10 parts of isobornyl acrylate are selected as the UV-curable monomers, that is, the photosensitive resin composition of this comparative example does not contain (meth)acrylate containing a long carbon chain.

[0079] Comparative Example 7 The only difference between this comparative example and Example 1 is that in this comparative example, 15 parts of 1,6-hexanediol diacrylate and 10 parts of dodecafluoroheptyl methacrylate are added as the UV-curable monomers, that is, the photosensitive resin composition of this comparative example does not contain bridged ring photocurable monomers.

[0080] The raw material ratios of Examples 1 to 5 and Comparative Examples 1 to 7 are shown in Table 1 below: Table 1 Raw material ratios of Examples 1 to 5 and Comparative Examples 1 to 7

[0081]

[0082] In order to verify the efficacy of the present invention, the applicant used 30 mW / cm 2 The film was cured by irradiation with UV light for 600s, and a 30μm thick cured film was obtained for performance testing. The specific aspects include the following: (1) Surface tension: The surface tension was tested using a surface tension meter (QBZY-2 surface tension meter). The test was conducted at 25°C. Defoaming centrifugation was performed before the test. Each sample was tested 5 times and the final data was averaged.

[0083] (2) Viscosity: The viscosity of the high-refractive precursor liquid was tested using a rotational rheometer (EVO type rotational viscometer). The test was performed at 25°C, using a 20 mm diameter conical rotor, and the shear rate was set to 0.01 s. -1 ~500s -1 , and select 10s -1 The viscosity of the samples under different shear rates was compared, and each sample was tested 5 times, and the final data was averaged.

[0084] (3) Refractive index: Pure organic inkjet printing with high refractive index ink was printed on a glass substrate and heated to 30 mW / cm2 in a nitrogen atmosphere. 2 The film was subjected to UV curing by UV irradiation under reduced pressure to produce a cured film layer having a size of 5 mm×15 mm×0.1 mm (width×length×thickness), which was then tested using an Abbe refractometer.

[0085] (4) Transmittance: The same method as the method for forming a cured pattern was followed except that no mask was used. The transmittance of the cured film in the visible light range of 400 nm to 800 nm was measured using a UV-visible spectrophotometer (U-3900 Hitachi).

[0086] (5) Photocuring rate: The encapsulation ink composition was inkjet printed on a glass substrate and subjected to a light curing rate of 30 mW / cm 2 The sample was subjected to UV curing for 120 s by UV irradiation under low temperature to produce a sample with a size of 3 cm × 7.5 cm × 18 μm (width × length × thickness), and then the encapsulant before curing and the film after curing were measured by FT-IR (Nicolet iS50, Thermo-Fisher) at 1635 cm -1 (C=C) and 1720cm -1 Absorption peak intensity near (C=O).

[0087] Photocuring rate (%) = |1-(F / S)|×100; Where F is the cured film at 1635cm -1 The absorption peak intensity near 1720cm -1 The ratio of the absorption peak intensities near 1635cm -1 The absorption peak intensity near 1720cm -1 The ratio of the absorption peak intensities near

[0088] (6) Dielectric constant: The dielectric constant of the composition was tested at 10 GHz using GB / T 1693-2007.

[0089] (7) Water vapor transmission rate: The water vapor transmission rate was measured using a water vapor transmission rate tester (PERMATRAN-W3 / 33, manufactured by MOCON) at 85° C. and 85% relative humidity for 24 hours.

[0090] The final test results are shown in Table 2 below: Table 2 Test results of Examples 1 to 5 and Comparative Examples 1 to 7

[0091]

[0092] The test results in Table 2 show that the photosensitive resin compositions formed by specific proportions of UV-curable monomers, photocrosslinking initiators and functional dispersions in Examples 1 to 5 of the present invention have excellent comprehensive performance. The viscosity and surface tension meet the requirements of inkjet printing, and have high curing rate, transmittance and refractive index. In particular, the dielectric constant is significantly reduced and can be controlled below 2. In addition, the photosensitive resin composition also has excellent mechanical properties and the ability to isolate water and oxygen, and the water vapor permeability is less than or equal to 2.8g / m 2 ·24h, can provide reliable performance guarantee for related applications, and effectively meet the stringent requirements of various complex application scenarios for comprehensive material performance.

[0093] However, the test results of comparative example 1 show that if the functional dispersion is not added to the formula, the dielectric reduction effect cannot be achieved; the test results of comparative example 2 show that without using a monofunctional reactive monomer for mixing pretreatment, the dielectric is difficult to be further reduced; the test results of comparative example 3 show that the particle size of the hollow microspheres is too large and easy to agglomerate, which will affect the transmittance and photocuring rate; the test results of comparative example 4 show that if the amount of functional dispersion added is too much, the water vapor permeability is significantly increased, which is not conducive to isolating water and oxygen; the test results of comparative example 5 show that the mass ratio of the monofunctional reactive monomer, the (meth) acrylate containing a long carbon chain and the bridge ring photocurable monomer is not within the ratio range given in the present invention, and the viscosity of the formed photosensitive resin composition is not within the appropriate range, which is not suitable for inkjet printing; the test results of comparative examples 6 and 7 show that the surface tension and viscosity of the ultraviolet light curable monomers using short carbon chain (meth) acrylates and dodecafluoroheptyl methacrylate are not within the appropriate range, which is not suitable for inkjet printing, and printing inks with low dielectric properties cannot be obtained, and the water vapor permeability is also high.

[0094] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0095] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A photosensitive resin composition for encapsulating optoelectronic components, characterized in that: The method comprises the following raw materials in parts by weight: 20 to 50 parts of an ultraviolet light curable monomer, 2 to 8 parts of a photocrosslinking initiator, and 5 to 30 parts of a functional dispersion liquid; Wherein, the functional dispersion includes monofunctional reactive monomers and hollow microspheres.

2. The photosensitive resin composition for encapsulating optoelectronic components according to claim 1, characterized in that: The mass ratio of the monofunctional reactive monomer to the hollow microspheres is (2-3):

1.

3. The photosensitive resin composition for encapsulating optoelectronic components according to claim 1, characterized in that: The monofunctional reactive monomer is an acrylic ester monomer, and has a viscosity of 2 cps to 10 cps.

4. The photosensitive resin composition for encapsulating optoelectronic components according to claim 1, characterized in that: The surface of the hollow microspheres is connected with an organic modification group, and the organic modification group is an acrylate group or a methacrylate group; The hollow microspheres include hollow silica; The particle size of the hollow microspheres is 10nm to 100nm.

5. The photosensitive resin composition for encapsulating optoelectronic components according to claim 1, characterized in that: The ultraviolet light curable monomer is a mixture of (meth)acrylate containing a long carbon chain and a bridged ring type photocurable monomer.

6. The photosensitive resin composition for encapsulating optoelectronic components according to claim 5, characterized in that: The mass ratio of the monofunctional reactive monomer, the (meth)acrylate containing a long carbon chain and the bridge ring photocurable monomer is (10-15): (15-30): (10-15).

7. The photosensitive resin composition for encapsulating optoelectronic components according to claim 5, characterized in that: The (meth)acrylate containing a long carbon chain includes one or more of 1,6-hexanediol diacrylate, 2-methyl-2-acrylic acid-1,10-decanediol, 2-methyl-2-acrylic acid-1,9-nonanediol dimethacrylate, 1,5-pentanediol dimethacrylate, 1,11-undecanediol dimethacrylate, 1,12-dodecanediol di(meth)acrylate, 1,13-tridecanediol dimethacrylate, 1,14-tetradecanediol di(meth)acrylate or 1,18-octadecanediyl dimethacrylate; The bridged ring photocurable monomers include bridged ring diacrylate monomers containing six to twenty-five carbon atoms.

8. The photosensitive resin composition for encapsulating optoelectronic components according to claim 1, characterized in that: The photocrosslinking initiator includes one or more of TPO, TEPO, 1173, 184, 819, 4-methoxybenzaldehyde, 4,4'-bis(dimethylamino)benzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, hydroxybenzophenone, bisbenzoylphenylphosphine oxide or benzoyldiphenylphosphine oxide.

9. A method for using the photosensitive resin composition for encapsulating optoelectronic components according to any one of claims 1 to 8, characterized in that: The specific steps include: Step 1: firstly attach the photosensitive resin composition to the surface of the optoelectronic component to be packaged by spin coating, doctor blade coating, screen printing or inkjet printing; Step 2: Next, the photosensitive resin composition is irradiated with ultraviolet light having a wavelength between 250 nm and 400 nm for 30 s to 600 s, and finally the photosensitive resin composition is cured to form an organic film having a thickness of 5 μm to 50 μm.

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