Preparation method of photosensitive resin, photosensitive resin prepared by preparation method and application of photosensitive resin

Abstract

The invention provides a preparation method of photosensitive resin, the photosensitive resin prepared by the preparation method and application, and relates to the technical field of photosensitive slurry. The preparation method of the photosensitive resin comprises the following steps: carrying out polymerization reaction on o-cresol formaldehyde epoxy resin and unsaturated binary acid in an organic solvent in the presence of a polymerization inhibitor and a catalyst to obtain an intermediate P; in the presence of a polymerization inhibitor and a catalyst, carrying out a grafting reaction on the intermediate P and 3-glycidyl ether oxypropyl triethoxy silane in an organic solvent to obtain an intermediate P-O; and in the presence of a polymerization inhibitor and a catalyst, reacting the intermediate P-O with an anhydride compound in an organic solvent to obtain the photosensitive resin P-O-S. The photosensitive resin provided by the invention has good chemical bonding strength and film-forming property on a substrate, has excellent wetting dispersion stability on an inorganic phase, and has good development resolution and development morphology; and the method has a good application prospect in photosensitive slurry.

Description

Technical Field

[0001] The present invention relates to the technical field of photosensitive pastes, and in particular to a method for preparing a photosensitive resin, the photosensitive resin prepared thereby, and applications thereof. Background Art

[0002] Currently, high-end industries such as artificial intelligence, 5G communications, new display screens, smart cars, integrated circuits, and flexible circuit boards are booming in my country. This has also prompted the midstream electronic component industry to develop towards the goals of small size, high-density wiring, multi-functional integration, and high reliability. Among them, electronic paste is one of the key materials for manufacturing these electronic components. It mainly plays a role in wiring conductivity, insulation protection, through-hole and current conduction control inside and outside the device. Its performance will have a decisive impact on the device's processing size and precision, mechanical properties, electrical properties, heat dissipation performance, and device reliability.

[0003] Limited by the development of screen printing equipment and process technologies, traditional screen-printed electronic pastes are no longer able to meet the manufacturing process requirements for high-end electronic components with wiring densities of line / space (L / S) ≤ 50 μm / 50 μm and via apertures (R) ≤ 50 μm. Consequently, the development of new electronic pastes and supporting processes has become necessary. Photosensitive pastes are a type of photosensitive electronic paste that integrates screen printing and photolithography techniques for construction. Their advantage lies in leveraging the flexibility and convenience of screen printing to form films on substrates of various sizes. Photolithography then uses a photochemical reaction to alter the solubility contrast in aqueous alkaline solutions between the exposed and non-exposed areas of the paste film, enabling the creation of fine circuits and / or vias with line / space ≤ 50 μm / 50 μm and / or via apertures R ≤ 50 μm.

[0004] Photosensitive resin is a core key raw material in photosensitive paste, which plays a decisive role in the dispersion stability, film forming properties, development resolution, development line fineness and adhesion of photosensitive paste. However, most of the photosensitive resins currently used in photosensitive paste are traditional modified epoxy acrylic resins, and this type of resin currently faces some performance problems: (1) After development, it is difficult to achieve high resolution results of 15um / 15um and below due to poor adhesion; (2) When the molecular weight is low and the acid value is high, line breakage is prone to occur, and when the molecular weight is high, it is prone to rough edges and unclean development problems; (3) The adhesion contribution capacity of the resin itself is limited, and additional adhesion-promoting functional additives need to be added to improve the overall adhesion of the photosensitive paste system.

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

[0006] One of the objects of the present invention is to provide a method for preparing a photosensitive resin, specifically a method for preparing a photosensitive resin for photosensitive paste that is soluble in a weak alkaline solution. The preparation method uses o-cresol epoxy resin as a matrix, and sequentially performs epoxy ring-opening reaction, coupling modification, and anhydride modification on the matrix, so that the photosensitive resin has good chemical bonding strength and film-forming properties on substrates such as ceramics, metal oxides, and glass. At the same time, it also has excellent wetting and dispersion stability on inorganic phases such as metal powder, ceramic powder, and inorganic glass powder, and further gives the photosensitive resin good development resolution and development morphology.

[0007] A second object of the present invention is to provide a photosensitive resin, which is prepared by the above-mentioned method for preparing the photosensitive resin.

[0008] The third purpose of the invention is to provide an application of a photosensitive resin in the preparation of photosensitive paste. The photosensitive resin prepared by the present invention has good application prospects in photosensitive pastes such as photosensitive silver paste, photosensitive silver-coated copper paste, and photosensitive ceramic paste.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted: In a first aspect, the present invention provides a method for preparing a photosensitive resin, the method comprising: (1) In the presence of a polymerization inhibitor and a catalyst, an o-cresol epoxy resin and an unsaturated dibasic acid are polymerized in an organic solvent to obtain an intermediate P; (2) in the presence of a polymerization inhibitor and a catalyst, the intermediate P and 3-glycidyloxypropyltriethoxysilane are subjected to a grafting reaction in an organic solvent to obtain an intermediate PO; (3) In the presence of a polymerization inhibitor and a catalyst, the intermediate PO and an acid anhydride compound are reacted in an organic solvent to obtain the photosensitive resin POS.

[0010] Furthermore, in step (1) and step (2), the intermediate P comprises any one or a combination of at least two of the intermediates represented by the following formulae Pa to Pc: ; Style Pa; ; Formula Pb;

[0011] Formula Pc; Wherein, x is an integer between 4 and 14.

[0012] Furthermore, step (1) specifically includes: An organic solvent and o-cresol-formaldehyde epoxy resin are mixed, stirred and heated to the first stage temperature for dissolution; after dissolution, a polymerization inhibitor and a catalyst are added, stirred and dissolved and heated to the second stage temperature; after the temperature stabilizes, an organic solution of an unsaturated dibasic acid is added dropwise, and the second stage temperature is maintained for polymerization reaction to obtain an intermediate P.

[0013] Furthermore, in step (1), the molar ratio of the unsaturated dibasic acid to the epoxy group in the o-cresol-formaldehyde epoxy resin is (0.85-1.2):1.

[0014] Furthermore, in step (1), the unsaturated dibasic acid includes any one of methylene succinic acid, maleic acid or glutaconic acid, or a combination of at least two thereof.

[0015] Furthermore, in step (1), the temperature of the first stage is 65-80°C.

[0016] Furthermore, in step (1), the temperature of the second stage is 95-110°C.

[0017] Furthermore, in step (1), the organic solution of the unsaturated dibasic acid is added dropwise within 1 hour.

[0018] Furthermore, in step (1), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the intermediate P is ≤5 mgKOH / g.

[0019] Furthermore, in step (2) and step (3), the intermediate PO comprises any one or a combination of at least two of the intermediates represented by the following formulae Pa-O to Pc-O:

[0020] Pa-O; ; Pb-O; ; Pc-O; Wherein, n is an integer between 2 and 8, and m is an integer between 2 and 6.

[0021] Furthermore, step (2) specifically includes: The intermediate P is controlled at the third stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve it; after dissolution, 3-glycidyloxypropyltriethoxysilane is added dropwise, and the third stage temperature is maintained for grafting reaction to obtain the intermediate PO.

[0022] Furthermore, the molar ratio of the unsaturated dibasic acid to 3-glycidyloxypropyltriethoxysilane is 1:(0.12-0.45).

[0023] Furthermore, in step (2), the temperature of the third stage is 85-95°C.

[0024] Furthermore, in step (2), the grafting reaction time is 3 to 5 hours.

[0025] Furthermore, the photosensitive resin POS in step (3) comprises any one or a combination of at least two of the photosensitive resins represented by the following formulas Pa-OS to Pc-OS: ; Formula Pa-OS; ; Formula Pb-OS; ; Type PC-OS; wherein Ra, Rb and Rc are each independently selected from , " ” represents the attachment site of the group; Wherein, M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time.

[0026] Furthermore, step (3) specifically includes: The intermediate PO is controlled at the fourth stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve it; after dissolution, an organic solution of an acid anhydride compound is added dropwise, and the fourth stage temperature is maintained for reaction to obtain the photosensitive resin POS.

[0027] Furthermore, the structure of the acid anhydride compound is shown in the following formula A: ; Formula A Wherein, M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time.

[0028] Furthermore, the molar ratio of the unsaturated dibasic acid to the acid anhydride compound to the acid anhydride compound is 1:(0.8-1.2).

[0029] Furthermore, in step (3), the temperature of the fourth stage is 75-85°C.

[0030] Furthermore, in step (3), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the photosensitive resin POS is ≤5 mgKOH / g.

[0031] Furthermore, in steps (1) to (3), the organic solvent includes any one of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate or dipropylene glycol methyl ether acetate, or a combination of at least two thereof.

[0032] Furthermore, in steps (1) to (3), the polymerization inhibitor includes p-hydroxyanisole and / or hydroquinone.

[0033] Furthermore, in steps (1) to (3), the amount of the polymerization inhibitor used is independently 0.1 to 0.6% of the mass of the o-cresol novolac epoxy resin.

[0034] Furthermore, in steps (1) to (3), the catalyst comprises N,N -Dimethylbenzylamine, N,N - Any one of dimethylaniline, triethylamine or triphenylphosphine, or a combination of at least two thereof.

[0035] Furthermore, in steps (1) to (3), the amount of the catalyst used is independently 0.4 to 1.2% of the mass of the o-cresol-formaldehyde epoxy resin.

[0036] In a second aspect, the present invention provides a photosensitive resin, which is prepared by the method for preparing the photosensitive resin according to the first aspect.

[0037] In a third aspect, the present invention provides a use of the photosensitive resin described in the second aspect in preparing a photosensitive paste.

[0038] Furthermore, the photosensitive paste includes any one of photosensitive silver paste, photosensitive silver-coated copper paste or photosensitive ceramic paste.

[0039] Compared with the prior art, the present invention has the following beneficial effects: (1) Compared with conventional photosensitive o-cresol epoxy acrylate resins, the photosensitive resin prepared by the present invention contains flexible siloxane segments (-Si(OC2H5)3), which can effectively reduce the glass transition temperature and overall rigidity of the resin system, and improve the flexibility and internal stress of the resin. This is conducive to the formation of more uniform, dense, crack-free films on substrates (such as ceramics, glass, metal oxides, etc.), especially during the drying or pre-baking process. In addition, the reactivity of the double bonds of the dibasic unsaturated acid esters in the photosensitive resin prepared by the present invention is moderate, and the molecular structure itself also has a certain degree of flexibility, which has less negative impact on film formation than acrylates (especially novolac epoxy acrylates containing rigid benzene rings).

[0040] (2) The siloxane segments in the photosensitive resin prepared by the present invention can form strong Si-O-Si or Si-OM (M=metal) covalent bonds with the hydroxyl groups on the substrate (such as ceramics, glass, metal oxides, etc.) and the surface of the inorganic powder particles, significantly improving the chemical bonding strength between the resin and the substrate / powder interface, which can not only improve the adhesion on the substrate, but also increase the wettability of the resin to the inorganic powder and the overall stability of the slurry. The hydroxyphthalic anhydride structure in the photosensitive resin prepared by the present invention can also form physical adsorption and hydrogen bonding with the powder surface, which has the effect of assisting in improving compatibility and dispersion stability. This is the key to achieving the preparation of high solid content and high performance photosensitive slurry.

[0041] (3) The photosensitive resin prepared by the present invention contains flexible siloxane segments and hydroxyphthalic anhydride structures, which can improve the density of the exposed area of ​​the photosensitive material, improve the anti-swelling property of the film layer in the exposed area and the lateral drilling of the developer, and ensure that the edge of the pattern is smooth and burr-free; and the hydroxyphthalic anhydride structure in the photosensitive resin has acidic carboxyl groups and acidic phenolic hydroxyl groups, and the dibasic unsaturated acid ester structure contains acidic carboxyl groups, which can greatly improve the hydrophilicity and dissolution rate of the unexposed area, forming a strong contrast with the insolubility of the exposed area, and can meet the stringent requirements of high-precision photosensitive paste for development resolution and contrast. DETAILED DESCRIPTION

[0042] Unless otherwise defined herein, scientific and technological terms used in conjunction with the present invention shall have the meanings commonly understood by those of ordinary skill in the art. The meaning and scope of the terms should be clear, however, in the case of any potential ambiguity, the definitions provided herein take precedence over any dictionary or external definitions. In this application, unless otherwise stated, the use of "or" means "and / or". In addition, the use of the term "including" and other forms is non-limiting.

[0043] It should be noted that the following description sets forth specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways than those described herein, and those skilled in the art may make similar generalizations without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0044] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0045] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted: In a first aspect, the present invention provides a method for preparing a photosensitive resin, the method comprising: (1) In the presence of a polymerization inhibitor and a catalyst, an o-cresol epoxy resin and an unsaturated dibasic acid are polymerized in an organic solvent to obtain an intermediate P; (2) in the presence of a polymerization inhibitor and a catalyst, the intermediate P and 3-glycidyloxypropyltriethoxysilane are subjected to a grafting reaction in an organic solvent to obtain an intermediate PO; (3) In the presence of a polymerization inhibitor and a catalyst, the intermediate PO and an acid anhydride compound are reacted in an organic solvent to obtain the photosensitive resin POS.

[0046] In the present invention, the photosensitive resin is based on an o-cresol-formaldehyde epoxy resin, which is subjected to an epoxy ring-opening reaction, coupling modification, and anhydride modification. This results in the photosensitive resin having good chemical bonding strength and film-forming properties on substrates such as ceramics, metal oxides, and glass. It also exhibits excellent wetting and dispersion stability on inorganic phases such as metal powder, ceramic powder, and inorganic glass powder, and further imparts good development resolution and development morphology to the photosensitive resin. Furthermore, the photosensitive resin prepared by the present invention has promising application prospects in photosensitive pastes such as photosensitive silver paste, photosensitive silver-coated copper paste, and photosensitive ceramic paste.

[0047] As an optional embodiment, in step (1) and step (2), the intermediate P comprises any one or a combination of at least two of the intermediates represented by the following formulae Pa to Pc: ; Style Pa; ; Formula Pb;

[0048] Type PC.

[0049] As an optional implementation, x is an integer between 4 and 14, for example, it can be 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or 14.

[0050] As an optional implementation, step (1) specifically includes: An organic solvent and o-cresol-formaldehyde epoxy resin are mixed, stirred and heated to the first stage temperature for dissolution; after dissolution, a polymerization inhibitor and a catalyst are added, stirred and dissolved and heated to the second stage temperature; after the temperature stabilizes, an organic solution of an unsaturated dibasic acid is added dropwise, and the second stage temperature is maintained for polymerization reaction to obtain an intermediate P.

[0051] As an optional embodiment, in step (1), the molar ratio of the unsaturated dibasic acid to the epoxy group in the o-cresol epoxy resin is (0.85-1.2):1, specifically but not limited to 0.85:1, 0.86:1, 0.87:1, 0.88:1, 0.89:1, 0.9:1, 0.91:1, 0.92:1, 0.93:1, 0.94:1, 0.95:1, 0.96:1, 0.97:1, 0.98:1, 0.99:1, 1:1, 1.01:1, 1.02:1, 1.03:1, 1.04:1, 1.05:1, 1.06:1, 1.07:1, 1.08:1, 1.09:1, 1.1:1, 1.11:1, 1.12:1, 1.13:1, 1.14:1, 1.15:1, 1.16:1, 1.17:1, 1.18:1, 1.19:1 or 1.2:1, etc.

[0052] As an optional embodiment, in step (1), the o-cresol epoxy resin can be any one of the o-cresol epoxy resins NPCN-701, NPCN-702, NPCN-703, NPCN-704 produced by Taiwan Changchun Company, or the o-cresol epoxy resins EOCN6650, EOCN6700, EOCN6800, EOCN6900 produced by Hunan Jiashengde Materials Technology Co., Ltd.

[0053] As an optional embodiment, in step (1), the unsaturated dibasic acid includes any one of methylene succinic acid, maleic acid or glutaconic acid, or a combination of at least two thereof.

[0054] As an optional embodiment, in step (1), the temperature of the first stage is 65-80°C, specifically but not limited to 65°C, 66°C, 67°C, 68°C, 69°C, 70°C, 71°C, 72°C, 73°C, 74°C, 75°C, 76°C, 77°C, 78°C, 79°C or 80°C, etc.

[0055] As an optional embodiment, in step (1), the temperature of the second stage is 95-110°C, specifically but not limited to 95°C, 96°C, 97°C, 98°C, 99°C, 100°C, 101°C, 102°C, 103°C, 104°C, 105°C, 106°C, 107°C, 108°C, 109°C or 110°C, etc.

[0056] As an optional embodiment, in step (1), the organic solution of the unsaturated dibasic acid is added dropwise within 1 h, specifically but not limited to 1 h, 58 min, 56 min, 55 min, 54 min, 52 min, 50 min, 48 min, 46 min, 45 min, 44 min, 42 min, 40 min, etc.

[0057] As an optional embodiment, in step (1), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the intermediate P is ≤5 mgKOH / g. Specifically but not limited to, 5 mgKOH / g, 4.5 mgKOH / g, 4 mgKOH / g, 3.5 mgKOH / g, 3 mgKOH / g, 2.5 mgKOH / g, 2 mgKOH / g, 1.5 mgKOH / g, 1 mgKOH / g, etc.

[0058] As an optional implementation, step (1) specifically includes the following steps: An organic solvent and o-cresol-formaldehyde epoxy resin are added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the temperature is raised to the first stage temperature at a certain stirring speed to fully dissolve. After complete dissolution, a certain amount of polymerization inhibitor and catalyst are continuously added to the round-bottom flask until fully stirred and dissolved. After dissolution is completed, the temperature is continuously raised to the second stage temperature. After the temperature stabilizes, a pre-dissolved unsaturated dibasic acid organic solution is slowly added dropwise using a constant pressure funnel. The addition is controlled to be completed within 1 hour, and the second stage temperature is maintained for a period of time. The acid value is tested at hourly intervals. The reaction is stopped when the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, and the intermediate P is obtained.

[0059] As an optional embodiment, in step (2) and step (3), the intermediate PO includes any one or a combination of at least two of the intermediates represented by the following formulae Pa-O to Pc-O:

[0060] Pa-O; ; Pb-O; ; Pc-O.

[0061] As an optional implementation, n is an integer between 2 and 8, for example, it can be 2, 3, 4, 5, 6, 7, or 8.

[0062] As an optional implementation, m is an integer between 2 and 6, for example, it can be 2, 3, 4, 5, or 6.

[0063] As an optional implementation, step (2) specifically includes: The intermediate P is controlled at the third stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve it; after dissolution, 3-glycidyloxypropyltriethoxysilane is added dropwise, and the third stage temperature is maintained for grafting reaction to obtain the intermediate PO.

[0064] As an optional embodiment, the molar ratio of the unsaturated dibasic acid to 3-glycidyloxypropyltriethoxysilane is 1:(0.12~0.45), specifically but not limited to 1:0.12, 1:0.14, 1:0.16, 1:0.18, 1:0.2, 1:0.22, 1:0.24, 1:0.26, 1:0.28, 1:0.3, 1:0.32, 1:0.34, 1:0.36, 1:0.38, 1:0.4, 1:0.42, 1:0.44 or 1:0.45, etc.

[0065] As an optional embodiment, in step (2), the temperature of the third stage is 85-95°C, specifically but not limited to 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C or 95°C.

[0066] As an optional embodiment, in step (2), the grafting reaction time is 3 to 5 h, specifically but not limited to 3 h, 3.2 h, 3.4 h, 3.5 h, 3.6 h, 3.8 h, 4 h, 4.2 h, 4.4 h, 4.5 h, 4.6 h, 4.8 h, 5 h, etc.

[0067] As an optional implementation, step (2) specifically includes: The temperature of the intermediate P is controlled at the third stage temperature, and a small amount of polymerization inhibitor and catalyst are continuously added to the round-bottom flask for dissolution. After the dissolution is completed, 3-glycidyloxypropyltriethoxysilane is slowly added dropwise using a constant pressure funnel for modification reaction for 3 to 5 hours to obtain the intermediate PO.

[0068] As an optional embodiment, the photosensitive resin POS in step (3) includes any one or a combination of at least two of the photosensitive resins represented by the following formulas Pa-OS to Pc-OS: ; Formula Pa-OS; ; Formula Pb-OS; ; Type PC-OS; wherein Ra, Rb and Rc are each independently selected from , " ” represents the attachment site of the group; Wherein, M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time.

[0069] As an optional implementation, step (3) specifically includes: The intermediate PO is controlled at the fourth stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve it; after dissolution, an organic solution of an acid anhydride compound is added dropwise, and the fourth stage temperature is maintained for reaction to obtain the photosensitive resin POS.

[0070] As an optional embodiment, the structure of the acid anhydride compound is shown in the following formula A: ; Formula A Wherein, M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time.

[0071] As an optional embodiment, the molar ratio of the unsaturated dibasic acid to the acid anhydride compound to the acid anhydride compound is 1:(0.8~1.2), specifically but not limited to 1:0.80, 1:0.82, 1:0.84, 1:0.86, 1:0.88, 1:0.9, 1:0.92, 1:0.94, 1:0.96, 1:0.98, 1:1, 1:1.02, 1:1.04, 1:1.06, 1:1.08, 1:1.1, 1:1.12, 1:1.14, 1:1.16, 1:1.18 or 1:1.2, etc.

[0072] As an optional embodiment, in step (3), the temperature of the fourth stage is 75-85°C, specifically but not limited to 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C or 85°C, etc.

[0073] As an optional embodiment, in step (3), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the photosensitive resin POS is ≤5 mgKOH / g. Specifically but not limitedly, 5 mgKOH / g, 4.5 mgKOH / g, 4 mgKOH / g, 3.5 mgKOH / g, 3 mgKOH / g, 2.5 mgKOH / g, 2 mgKOH / g, 1.5 mgKOH / g, 1 mgKOH / g, etc. can be selected.

[0074] As an optional implementation, step (3) specifically includes: The reaction liquid of the intermediate PO is maintained at the fourth stage temperature, and a certain amount of inhibitor and catalyst are continuously added. Then, the pre-dissolved acid anhydride compound is slowly added dropwise using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value. The reaction is stopped when the difference in the actual acid value between the last two samples is less than or equal to 5 mgKOH / g. The organic solvent is then partially removed by vacuum distillation to obtain a photosensitive resin POS product.

[0075] As an optional embodiment, in steps (1) to (3), the organic solvent includes any one of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate or dipropylene glycol methyl ether acetate, or a combination of at least two thereof.

[0076] As an optional embodiment, in steps (1) to (3), the polymerization inhibitor includes p-hydroxyanisole and / or hydroquinone.

[0077] As an optional embodiment, in steps (1) to (3), the amount of the polymerization inhibitor used is independently 0.1% to 0.6% of the mass of the o-cresol novolac epoxy resin, specifically but not limited to 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, etc.

[0078] As an optional embodiment, in steps (1) to (3), the catalyst includes N,N -Dimethylbenzylamine, N,N - Any one of dimethylaniline, triethylamine or triphenylphosphine, or a combination of at least two thereof.

[0079] As an optional embodiment, in steps (1) to (3), the amount of the catalyst used is independently 0.4-1.2% of the mass of the o-cresol epoxy resin, specifically but not limited to 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, etc.

[0080] In a second aspect, the present invention provides a photosensitive resin, which is prepared by the method for preparing the photosensitive resin according to the first aspect.

[0081] In a third aspect, the present invention provides a use of the photosensitive resin described in the second aspect in preparing a photosensitive paste.

[0082] As an optional embodiment, the photosensitive paste includes any one of photosensitive silver paste, photosensitive silver-coated copper paste or photosensitive ceramic paste.

[0083] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples were prepared according to existing methods or directly purchased from the market.

[0084] Example 1 This embodiment provides a photosensitive resin P a1 -O-S1, the photosensitive resin P a1 The synthesis process of -O-S1 is as follows: (1) Preparation of intermediate P a1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved itaconic acid hot solution (wherein the molar ratio of itaconic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is ≤5 mgKOH / g, the reaction stops, and the intermediate P is obtained. a1 ; (2) Preparation of intermediate P a1 -O The intermediate P prepared in step (1) a1 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to itaconic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P a1 -O; (3) Preparation of photosensitive resin P a1 -O-S1 The intermediate P prepared in step (2) a1 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3-hydroxyphthalic anhydride solution (the molar amount of 3-hydroxyphthalic anhydride relative to itaconic acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference in the measured acid value between the last two samples is ≤5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pa1-O-S1.

[0085] The structural formula of the photosensitive resin Pa1-O-S1 is as follows: ; Among them, Ra is .

[0086] Example 2 This embodiment provides a photosensitive resin P a1 -O-S2, the photosensitive resin P a1 The synthesis process of -O-S2 is as follows: (1) Preparation of intermediate P a1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved itaconic acid hot solution (wherein the molar ratio of itaconic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is ≤5 mgKOH / g, the reaction stops, and the intermediate P is obtained. a1 ; (2) Preparation of intermediate P a1 -O The intermediate P prepared in step (1) a1 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to itaconic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P a1-O; (3) Preparation of photosensitive resin P a1 -O-S2 The reaction solution of intermediate Pa1-O was maintained at 80°C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3,6-dihydroxyphthalic anhydride solution (the molar amount of 3,6-dihydroxyphthalic anhydride relative to itaconic acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference in the measured acid value between the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pa1-O-S2.

[0087] The structural formula of the photosensitive resin Pa1-O-S2 is as follows: ; Among them, Ra is .

[0088] Example 3 This embodiment provides a photosensitive resin P b1 -O-S1, the photosensitive resin P b1 The synthesis process of -O-S1 is as follows: (1) Preparation of intermediate P b1 Ethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved maleic acid hot solution (wherein the molar ratio of maleic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, the reaction is stopped to obtain the intermediate P b1 ; (2) Preparation of intermediate P b1 -O The intermediate P prepared in step (1) b1The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N- Dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar weight of 0.15 relative to maleic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P b1 -O; (3) Preparation of photosensitive resin P b1 -O-S1 The intermediate P prepared in step (2) b1 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3-hydroxyphthalic anhydride solution (the molar amount of 3-hydroxyphthalic anhydride relative to itaconic acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference in the measured acid value between the last two samples is ≤5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pb1-O-S1.

[0089] The structural formula of the photosensitive resin Pb1-O-S1 is as follows: ; Among them, R b for .

[0090] Example 4 This embodiment provides a photosensitive resin P b2 -O-S3, the photosensitive resin P b2 The synthesis process of -O-S3 is as follows: (1) Preparation of intermediate P b2 Diethylene glycol methyl ether acetate and o-cresol epoxy resin EOCN6650 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C at a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of phenolic acid were added to the round-bottom flask, respectively, relative to the mass of o-cresol epoxy resin. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved maleic acid hot solution (wherein the molar ratio of maleic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, the reaction is stopped to obtain the intermediate P b2 ; (2) Preparation of intermediate P b2 -O The intermediate P prepared in step (1) b2 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole polymerization inhibitor (0.2% relative to the mass of o-cresol epoxy resin) and N,N -Dimethylbenzylamine catalyst (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to maleic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P b2 -O; (3) Preparation of photosensitive resin P b2 -O-S3 The intermediate P prepared in step (2) b2 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole polymerization inhibitor (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine catalyst (0.8% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 4-hydroxyphthalic anhydride solution (the molar amount of 4-hydroxyphthalic anhydride relative to itaconic acid is 1.2) through a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference between the measured acid values ​​of the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pb2-O-S3.

[0091] The structural formula of the photosensitive resin Pb2-O-S3 is as follows: ; Among them, R b for .

[0092] Example 5 This embodiment provides a photosensitive resin P c1 -O-S1, the photosensitive resin P c1 The synthesis process of -O-S1 is as follows: (1) Preparation of intermediate Pc1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After the mixture was completely dissolved, 0.3% p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine was stirred and dissolved until fully dissolved. After the dissolution was completed, the temperature was continued to rise to 100 ° C. After the temperature stabilized, the pre-dissolved hot solution of glutaconic acid (wherein the molar ratio of glutaconic acid to the epoxy group in o-cresol epoxy resin was 1:1) was slowly added dropwise using a constant pressure funnel. The addition was controlled to be completed within 1 hour, and the temperature was maintained at 100 ° C for a period of time. The acid value was tested by sampling every half an hour. The reaction was stopped when the difference between the measured value and the theoretical acid value was less than or equal to 5 mgKOH / g to obtain the intermediate P. c1 ; (2) Preparation of intermediate P c1 -O The intermediate P prepared in step (1) c1 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to glutaconic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P c1 -O; (3) Preparation of photosensitive resin P c1 -O-S1 The intermediate P prepared in step (2) c1 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3-hydroxyphthalic anhydride solution (the molar amount of 3-hydroxyphthalic anhydride relative to glutaric acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference between the measured acid values ​​of the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pc1-O-S1.

[0093] The structural formula of the photosensitive resin Pc1-O-S1 is as follows:

[0094] Among them, R c for .

[0095] Example 6 This embodiment provides a photosensitive resin P c2 -O-S2, the photosensitive resin P c2 The synthesis process of -O-S2 is as follows: (1) Preparation of intermediate P c2 Diethylene glycol methyl ether acetate and o-cresol epoxy resin EOCN6650 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C at a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved hot solution of glutaconic acid (wherein the molar ratio of glutaconic acid to the epoxy group in o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, the reaction is stopped to obtain the intermediate P c2 ; (2) Preparation of intermediate P c2 -O The intermediate P prepared in step (1) c2 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to glutaconic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P c2 -O; (3) Preparation of photosensitive resin P c2 -O-S2 The intermediate P prepared in step (2) c2 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3,6-dihydroxyphthalic anhydride solution (the molar amount of 3,6-dihydroxyphthalic anhydride relative to glutaric acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference in the actual acid value between the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to use reduced pressure distillation to remove part of the organic solvent to obtain the photosensitive resin Pc2-O-S2.

[0096] The structural formula of the photosensitive resin Pc2-O-S2 is as follows:

[0097] Among them, R c for .

[0098] Comparative Example 1 This comparative example provides a photosensitive resin P a1 , the photosensitive resin P a1 The synthesis process is as follows: Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C at a stirring speed of 200 rpm / min and fully dissolved. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of N, N-dimethylbenzylamine were added to the round-bottom flask relative to the mass of the o-cresol epoxy resin, respectively, and stirred and dissolved. After dissolution, the mixture was heated to 100°C. After the temperature stabilized, the pre-dissolved itaconic acid hot solution (wherein the molar ratio of itaconic acid to the epoxy group in the o-cresol epoxy resin was 1:1) was slowly added dropwise using a constant pressure funnel. The addition was completed within 1 h, and the temperature was maintained at 100°C for a period of time. The acid value was tested at intervals of half an hour. The reaction was stopped when the difference between the measured value and the theoretical acid value was less than or equal to 5 mgKOH / g. The reduced pressure distillation method was continued to remove part of the organic solvent to obtain a photosensitive resin P a1 .

[0099] The photosensitive resin P a1 The structural formula is as follows: .

[0100] Comparative Example 2 This comparative example provides a photosensitive resin P a1 -O, the photosensitive resin P a1 The synthesis process of -O is as follows: (1) Preparation of intermediate P a1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved itaconic acid hot solution (wherein the molar ratio of itaconic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, the reaction is stopped to obtain the intermediate P a1 ; (2) Preparation of photosensitive resin P a1 -O The intermediate P prepared in step (1) a1 The temperature was controlled at 90°C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin), after the dissolution is completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to itaconic acid is slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the photosensitive resin P a1 -O.

[0101] The photosensitive resin P a1 The structural formula of -O is as follows: .

[0102] Comparative Example 3 This comparative example provides a photosensitive resin P b1 -S1, the photosensitive resin P b1 -S1 synthesis process is as follows: (1) Preparation of intermediate P b1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved maleic acid hot solution (wherein the molar ratio of maleic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is less than or equal to 5 mgKOH / g, the reaction is stopped to obtain the intermediate P a1 ; (2) Preparation of photosensitive resin P b1 -S1 The intermediate P a1 The reaction solution was maintained at 80 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved 3-hydroxyphthalic anhydride solution (the molar amount of 3-hydroxyphthalic anhydride relative to maleic acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference between the actual acid values ​​of the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to use reduced pressure distillation to remove part of the organic solvent to obtain a photosensitive resin P b1 -S1.

[0103] The photosensitive resin P b1 The structural formula of -S1 is as follows: .

[0104] Comparative Example 4 This comparative example provides a photosensitive resin P a1 -O-S0, the photosensitive resin P a1 -O-S0 synthesis process is as follows: (1) Preparation of intermediate P a1 Diethylene glycol methyl ether acetate and o-cresol epoxy resin NPCN-702 were added to a four-necked round-bottom flask equipped with a mechanical stirring paddle, a thermometer, a reflux condenser and a thermometer in sequence, and the mixture was heated to 75°C with a stirring speed of 200 rpm / min to fully dissolve. After complete dissolution, 0.3% of p-hydroxyanisole and 1% of o-cresol epoxy resin were added to the round-bottom flask respectively. N,N -dimethylbenzylamine until fully stirred and dissolved, continue to heat to 100 ° C after the dissolution is completed, and after the temperature stabilizes, slowly add the pre-dissolved itaconic acid hot solution (wherein the molar ratio of itaconic acid to the epoxy group in the o-cresol epoxy resin is 1:1) using a constant pressure funnel, and control the addition to be completed within 1 hour, and maintain the temperature at 100 ° C for a period of time, and take samples every half an hour to test the acid value. When the difference between the measured value and the theoretical acid value is ≤5 mgKOH / g, the reaction stops, and the intermediate P is obtained. a1 ; (2) Preparation of intermediate P a1 -O The intermediate P prepared in step (1) a1 The temperature was controlled at 90 ° C, and a small amount of p-hydroxyanisole (0.2% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.8% relative to the mass of o-cresol epoxy resin) was dissolved, and after the dissolution was completed, 3-glycidyloxypropyltriethoxysilane with a molar amount of 0.15 relative to itaconic acid was slowly added dropwise using a constant pressure funnel for modification reaction for 4 hours to obtain the intermediate P a1 -O; (3) Preparation of photosensitive resin P a1 -O-S0 The intermediate P prepared in step (2) a1 -O reaction solution was maintained at 80 ° C, and a small amount of hydroxyanisole (0.1% relative to the mass of o-cresol epoxy resin) and N,N -dimethylbenzylamine (0.6% relative to the mass of o-cresol epoxy resin), and then slowly add the pre-dissolved phthalic anhydride solution (the molar amount of phthalic anhydride relative to itaconic acid is 1.2) using a constant pressure funnel. After the addition is completed, samples are taken every half hour to measure the acid value until the difference between the measured acid values ​​of the last two samples is less than or equal to 5 mgKOH / g. Stop the reaction and continue to remove part of the organic solvent by reduced pressure distillation to obtain the photosensitive resin Pa1-O-S0.

[0105] The structural formula of the photosensitive resin Pa1-O-S0 is as follows: ; Among them, Ra is .

[0106] Comparative Example 5 Commercially available modified o-cresol acrylic resin B-196S (produced by Guangdong Boxing New Material Technology Co., Ltd.)

[0107] Test Case Test samples: the photosensitive resins provided in Examples 1 to 6 and the photosensitive resins provided in Comparative Examples 1 to 5; Test method: (1) Preparation of photosensitive composition: 42 parts of the photosensitive resin of the corresponding sample, 0.5 parts of 2-isopropylthioxanthone, 2 parts of 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, 46 parts of diethylene glycol methyl ether acetate, 3 parts of 1,6-hexanediol diacrylate, and 6 parts of dipentaerythritol hexaacrylate were dissolved and compounded to prepare a photosensitive composition.

[0108] (2) Photosensitive composition process test: (i) Construction substrate: 50mm*50mm alumina ceramic substrate, 50mm*50mm ITO substrate, 100mm*100mm ITO / PET film; (ii) Glue coating: 500rpm*5sec+2500rpm*30sec; (iii) Pre-baking: Hot plate, 60℃@10min; (iv) Exposure: i-line UV lithography machine, 150 mj / cm 2 (v) Development: 0.6% Na2CO3 developer, development time 23±2℃; (vi) Post-development rinsing: high-pressure water rinse for 3 minutes; (vii) Post-development drying: blow dry with high-purity nitrogen.

[0109] (3) Adhesion after curing: The cured photosensitive composition was tested with reference to the standard ASTM D3359; Development performance: The resolution, line edges, and whether there were any breakages on the substrate after development and drying were observed using an optical microscope.

[0110] The specific test results are shown in Table 1 below: Table 1

[0111] As can be seen from Table 1, the photosensitive compositions prepared in Examples 1 to 6 have good adhesion and developing properties, while Comparative Example 1, which does not contain a flexible siloxane segment and a hydroxyphthalic anhydride structure, exhibits poor adhesion and developing properties. Similarly, Comparative Example 2, which does not contain a hydroxyphthalic anhydride structure, and Comparative Example 3, which does not contain a flexible siloxane segment, also fail to exhibit good cured adhesion and / or developing properties. Comparative Example 4, in which the hydroxyphthalic anhydride structure is replaced with a hydroxyl-free phthalic anhydride structure, also fails to achieve the expected developing performance results. Comparative Example 5, which is prepared using a commercially available photosensitive modified o-cresol acrylic resin, also exhibits poor cured adhesion and developing properties due to the brittleness of its resin skeleton, insufficient swelling resistance of the exposed area after curing, and insufficient density of carboxyl or phenolic hydroxyl groups in the resin.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a photosensitive resin, characterized in that: The preparation method of the photosensitive resin comprises: (1) In the presence of a polymerization inhibitor and a catalyst, an o-cresol epoxy resin and an unsaturated dibasic acid are polymerized in an organic solvent to obtain an intermediate P; (2) in the presence of a polymerization inhibitor and a catalyst, the intermediate P and 3-glycidyloxypropyltriethoxysilane are subjected to a grafting reaction in an organic solvent to obtain an intermediate PO; (3) In the presence of a polymerization inhibitor and a catalyst, the intermediate PO and an acid anhydride compound are reacted in an organic solvent to obtain the photosensitive resin POS.

2. The method for preparing a photosensitive resin according to claim 1, wherein: In step (1) and step (2), the intermediate P comprises any one or a combination of at least two of the intermediates represented by the following formulae Pa to Pc: ； Style Pa; ； Formula Pb; Formula Pc; Wherein, x is an integer between 4 and 14.

3. The method for preparing a photosensitive resin according to claim 1, wherein: Step (1) specifically includes: An organic solvent and an o-cresol epoxy resin are mixed, stirred, and heated to a first-stage temperature for dissolution; after dissolution, a polymerization inhibitor and a catalyst are added, stirred and dissolved, and the temperature is raised to a second-stage temperature; after the temperature stabilizes, an organic solution of an unsaturated dibasic acid is added dropwise, and the second-stage temperature is maintained for polymerization reaction to obtain an intermediate P; Preferably, in step (1), the molar ratio of the unsaturated dibasic acid to the epoxy group in the o-cresol-formaldehyde epoxy resin is (0.85-1.2):1; Preferably, in step (1), the unsaturated dibasic acid comprises any one of methylene succinic acid, maleic acid or glutaconic acid, or a combination of at least two thereof; Preferably, in step (1), the temperature of the first stage is 65-80°C; Preferably, in step (1), the temperature of the second stage is 95-110°C; Preferably, in step (1), the organic solution of the unsaturated dibasic acid is added dropwise within 1 h; Preferably, in step (1), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the intermediate P is ≤5 mgKOH / g.

4. The method for preparing a photosensitive resin according to claim 1, wherein: In step (2) and step (3), the intermediate PO includes any one or a combination of at least two of the intermediates represented by the following formulae Pa-O to Pc-O: Pa-O; ； Pb-O; ； Pc-O; Wherein, n is an integer between 2 and 8, and m is an integer between 2 and 6.

5. The method for preparing a photosensitive resin according to claim 1, wherein: Step (2) specifically includes: The intermediate P is controlled at the third stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve the intermediate P; after dissolution, 3-glycidyloxypropyltriethoxysilane is added dropwise, and the third stage temperature is maintained for a grafting reaction to obtain the intermediate PO; Preferably, the molar ratio of the unsaturated dibasic acid to 3-glycidoxypropyltriethoxysilane is 1:(0.12-0.45); Preferably, in step (2), the temperature of the third stage is 85-95°C; Preferably, in step (2), the grafting reaction time is 3 to 5 hours.

6. The method for preparing a photosensitive resin according to claim 1, wherein: The photosensitive resin POS in step (3) includes any one or a combination of at least two of the photosensitive resins represented by the following formulas Pa-OS to Pc-OS: ； Formula Pa-OS; ； Formula Pb-OS; ； Type PC-OS; wherein Ra, Rb and Rc are each independently selected from , " ” represents the attachment site of the group; Wherein, M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time.

7. The method for preparing a photosensitive resin according to claim 1, wherein: Step (3) specifically includes: The intermediate PO is controlled at the fourth stage temperature, and a polymerization inhibitor and a catalyst are added to dissolve it; after it is dissolved, an organic solution of an acid anhydride compound is added dropwise, and the fourth stage temperature is maintained for reaction to obtain the photosensitive resin POS; Preferably, the structure of the acid anhydride compound is as shown in the following formula A: ； Formula A wherein M1, M2, M3, and M4 are each independently selected from -H or -OH, and M1, M2, M3, and M4 are not selected from -H at the same time; Preferably, the molar ratio of the unsaturated dibasic acid to the acid anhydride compound to the acid anhydride compound is 1:(0.8-1.2); Preferably, in step (3), the temperature of the fourth stage is 75-85°C; Preferably, in step (3), the criterion for stopping the reaction is: the reaction stops when the difference between the measured value and the theoretical acid value of the photosensitive resin POS is ≤5 mgKOH / g.

8. The method for preparing a photosensitive resin according to claim 1, wherein: In steps (1) to (3), the organic solvent includes any one of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate or dipropylene glycol methyl ether acetate, or a combination of at least two thereof; Preferably, in steps (1) to (3), the polymerization inhibitor includes p-hydroxyanisole and / or hydroquinone; Preferably, in steps (1) to (3), the amount of the polymerization inhibitor used is independently 0.1 to 0.6% of the mass of the o-cresol novolac epoxy resin; Preferably, in steps (1) to (3), the catalyst comprises N,N -Dimethylbenzylamine, N,N - any one of dimethylaniline, triethylamine or triphenylphosphine, or a combination of at least two; Preferably, in steps (1) to (3), the amount of the catalyst used is independently 0.4 to 1.2% of the mass of the o-cresol-formaldehyde epoxy resin.

9. A photosensitive resin, characterized in that: The photosensitive resin is prepared by the method for preparing the photosensitive resin according to any one of claims 1 to 8.

10. Use of the photosensitive resin according to claim 9 in preparing photosensitive paste; And / or, the photosensitive paste includes any one of photosensitive silver paste, photosensitive silver-coated copper paste or photosensitive ceramic paste.

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