Photoetching flexible end paste resin composition as well as preparation method and application thereof

Abstract

The invention provides a photoetching flexible end paste resin composition as well as a preparation method and application thereof. The photoetching flexible end paste resin composition comprises aliphatic photosensitive resin and fluorine-containing auxiliary resin, the molecular structure of the aliphatic photosensitive resin contains carbon-carbon double bonds; the molecular structure of the fluorine-containing auxiliary resin contains carboxyl; the mass ratio of the aliphatic photosensitive resin to the fluorine-containing auxiliary resin is (4-6): 1. According to the photoetching flexible end paste resin composition disclosed by the invention, the aliphatic photosensitive resin and the fluorine-containing auxiliary resin are compounded according to a specific content, so that the photoetching flexible end paste resin composition has proper developing time, good hole filling effect and hole wetting effect and excellent long-term ultraviolet aging resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a photolithography flexible end paste resin composition and a preparation method and application thereof. Background Art

[0002] Electronic components are an indispensable part of modern electronic devices. They realize various functions by generating electrical signals. Electronic components include inductors, resistors, capacitors, etc. Usually, electronic components are terminally processed by photolithography electronic conductive paste to transmit electrical signals.

[0003] At present, photolithography electronic conductive paste is a metal paste, such as conductive silver paste, and the resin in the photolithography electronic conductive paste mostly adopts an aromatic resin system. However, aromatic resin has a few shortcomings in the printing and wiring of end paste. First, when the end paste of electronic components is printed on materials with holes on the surface, the holes cannot be wetted and filled, resulting in possible errors in the transmission of electrical signals. Second, aromatic resin paste has poor long-term UV aging resistance. When used outdoors for a long time, it needs to be replaced and maintained regularly, which increases costs.

[0004] Therefore, developing a photolithography flexible end paste resin material with good hole filling and hole wetting effects and good long-term UV aging resistance is an urgent problem to be solved in the field. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a photolithography flexible end paste resin composition and its preparation method and application. The photolithography flexible end paste resin composition solves the problems in the prior art that the photolithography electronic conductive paste has poor hole filling effect and hole wetting effect and poor long-term UV aging resistance.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a photolithography flexible end paste resin composition, which comprises an aliphatic photosensitive resin and a fluorine-containing auxiliary resin; the aliphatic photosensitive resin contains a carbon-carbon double bond in its molecular structure; the fluorine-containing auxiliary resin contains a carboxyl group in its molecular structure; the mass ratio of the aliphatic photosensitive resin to the fluorine-containing auxiliary resin is (4~6):1.

[0008] In the present invention, the aliphatic photosensitive resin can improve the hole filling effect and wetting effect of the conductive paste, and can also improve the long-term ultraviolet aging resistance of the paste; the fluorine-containing auxiliary resin can adjust the development time, so that the conductive paste has a suitable development time, and can improve the long-term ultraviolet aging resistance of the conductive paste; the aliphatic photosensitive resin and the fluorine-containing auxiliary resin are compounded in specific contents, so that the photolithography flexible end paste resin composition has a suitable development time, good hole filling effect and wetting effect, and excellent long-term ultraviolet aging resistance.

[0009] In the present invention, the mass ratio of the aliphatic photosensitive resin to the fluorine-containing auxiliary resin is (4-6):1, which refers to the solid mass ratio of the two, excluding the solvent; wherein the specific values ​​in (4-6) can be, for example, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6, etc.

[0010] In the present invention, the mass ratio of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin is within a specific range, which can control the development time within an appropriate range to ensure the development effect; and can ensure that the resin composition has good hole filling effect and wetting effect and excellent long-term UV aging resistance.

[0011] Preferably, the raw materials for preparing the aliphatic photosensitive resin include fluorine-containing epoxy acrylic resin and acrylic acid.

[0012] Preferably, the molar ratio of the acrylic acid to the epoxy group in the fluorinated epoxy acrylic resin is (1.05-1.2):1, wherein the specific value in (1.05-1.2) can be, for example, 1.05, 1.055, 1.06, 1.065, 1.07, 1.075, 1.08, 1.085, 1.09, 1.095, 1.1, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.2, etc.

[0013] In the present invention, the carboxyl group in the acrylic acid can react with the epoxy group in the fluorine-containing epoxy acrylic resin, thereby introducing a carbon-carbon double bond into the photosensitive resin, so that the resin composition can undergo a photocuring reaction, while improving the development effect, improving production efficiency, and reducing costs; if the acrylic acid content is too low, the content of double bonds in the aliphatic photosensitive resin on the main chain segment is reduced, resulting in insufficient crosslinking and poor development effect; if the acrylic acid content is high, the cost is high, resulting in material waste.

[0014] Preferably, the raw materials for preparing the fluorine-containing epoxy acrylic resin include monofunctional acrylate monomers and a first initiator.

[0015] Preferably, the monofunctional acrylate monomer includes a first C1-C6 alkyl acrylate, an epoxy acrylate and a first fluorine-containing acrylate.

[0016] In the present invention, the C1~C6 alkyl ester refers to a straight or branched alkyl ester having 1 to 6 carbon atoms, exemplarily including methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester, n-pentyl ester, isopentyl ester, neopentyl ester, n-hexyl ester, etc.; if the same expression is used below, it means the same meaning.

[0017] Preferably, the mass ratio of the first C1-C6 alkyl acrylate, epoxy acrylate and first fluorinated acrylate is (30-45):(1-3):(7-10), wherein the specific value in (30-45) can be, for example, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, etc.; the specific value in (1-3) can be, for example, 1, 1 .1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, etc.; the specific value in (7-10) can be, for example, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9, 9.2, 9.4, 9.6, 9.8, 10, etc. Preferably, the mass of the first initiator is 1.3-2% of the total mass of the monofunctional acrylate monomer, for example, it can be 1.3%, 1.35%, 1.4%, 1.45%, 1.5%, 1.55%, 1.6%, 1.65%, 1.7%, 1.75%, 1.8%, 1.85%, 1.9%, 1.95%, 2%, etc.

[0018] In the present invention, the first initiator is selected from commonly used initiators in the art, and any initiator that can initiate a polymerization reaction can be selected, including but not limited to peroxide initiators, azo initiators, redox initiators, etc.; the peroxide initiators include benzoyl peroxide, cumene peroxide, potassium persulfate, sodium persulfate, ammonium persulfate, etc.; the azo initiators include but are not limited to azobisisobutyronitrile (AIBN), azobisisoheptanenitrile, etc.

[0019] Preferably, the first C1-C6 alkyl acrylate includes at least one of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-propyl methacrylate, n-propyl acrylate, isopropyl methacrylate, isopropyl acrylate, n-butyl methacrylate or n-butyl acrylate.

[0020] Preferably, the first C1-C6 alkyl acrylate comprises methyl methacrylate and ethyl methacrylate; the mass ratio of methyl methacrylate to ethyl methacrylate is (20-30):(10-15), wherein the specific value in (20-30) can be, for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30; the specific value in (10-15) can be, for example, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, etc.

[0021] In the present invention, the monofunctional acrylic ester monomer is compounded with monomers of a specific composition and a specific mass ratio, which is beneficial to improving the hole filling effect and hole wetting effect of the resin composition.

[0022] Preferably, the epoxy acrylate comprises glycidyl methacrylate.

[0023] Preferably, H groups on at least two carbon atoms in the first fluorine-containing acrylate are all replaced by F, for example, H groups on 2 carbon atoms are all replaced by F, H groups on 6 carbon atoms are all replaced by F, H groups on 8 carbon atoms are all replaced by F, etc.

[0024] In the present invention, the first fluorine-containing acrylic ester includes fluorine-containing acrylic C1~C8 alkyl esters, and the C1~C8 alkyl esters refer to straight-chain or branched alkyl esters with 1 to 8 carbon atoms, and exemplarily include methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester, n-pentyl ester, isopentyl ester, neopentyl ester, n-hexyl ester, n-heptyl ester, n-octyl ester, etc.

[0025] Preferably, the first fluorine-containing acrylate includes 1,1,1,3,3,3-hexafluoroisopropyl methacrylate.

[0026] Preferably, the raw materials for preparing the fluorine-containing auxiliary resin include monomers and a second initiator.

[0027] Preferably, the monomers include a second C1-C6 alkyl acrylate, a styrene monomer, methacrylic acid and a second fluorine-containing acrylate.

[0028] Preferably, the mass ratio of the second C1-C6 alkyl acrylate, the styrene monomer, methacrylic acid and the second fluorinated acrylate is (20-30): (10-15): (1-3): (7-10); wherein the specific value in (20-30) can be, for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30; the specific value in (10-15) can be, for example, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, etc.; the specific value in (1-3) can be, for example, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, etc.; the specific values ​​in (7-10) can be, for example, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9, 9.2, 9.4, 9.6, 9.8, 10, etc.

[0029] In the present invention, the monomers in the fluorine-containing auxiliary resin are compounded with monomers of specific composition and specific mass ratio, which is beneficial to improving the hole filling effect and hole wetting effect of the resin composition; and compared with acrylic acid, methacrylic acid with a slightly weaker cross-linking effect is used, which can avoid the phenomenon of falling off in pieces during development, which is beneficial to control the development time within a suitable range and improve the development effect.

[0030] Preferably, the mass of the second initiator is 3.3-4.2% of the total mass of the monomers, for example, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4%, 4.1%, 4.2%, etc.

[0031] In the present invention, the second initiator is selected from commonly used initiators in the art, and any initiator that can initiate a polymerization reaction may be used, including but not limited to peroxide initiators, azo initiators, redox initiators, etc.; the peroxide initiators include benzoyl peroxide, cumene peroxide, potassium persulfate, sodium persulfate, ammonium persulfate, etc.; the azo initiators include but are not limited to azobisisobutyronitrile (AIBN), azobisisoheptanenitrile, etc.

[0032] Preferably, the second C1-C6 alkyl acrylate includes at least one of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-propyl methacrylate, n-propyl acrylate, isopropyl methacrylate, isopropyl acrylate, n-butyl methacrylate or n-butyl acrylate.

[0033] Preferably, H groups on at least two carbon atoms in the second fluorine-containing acrylate are all replaced by F, for example, H groups on 2 carbon atoms are all replaced by F, H groups on 6 carbon atoms are all replaced by F, H groups on 8 carbon atoms are all replaced by F, etc.

[0034] In the present invention, the second fluorine-containing acrylic ester includes fluorine-containing acrylic C1~C8 alkyl esters, and the C1~C8 alkyl esters refer to straight-chain or branched alkyl esters with 1 to 8 carbon atoms, and exemplarily include methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester, n-pentyl ester, isopentyl ester, neopentyl ester, n-hexyl ester, n-heptyl ester, n-octyl ester, etc.

[0035] Preferably, the second fluorine-containing acrylate includes 1,1,1,3,3,3-hexafluoroisopropyl methacrylate.

[0036] Preferably, the photolithography flexible end paste resin composition further comprises a solvent and / or an auxiliary agent.

[0037] Preferably, the solvent comprises nonafluorobutyl ethyl ether and / or dimethylacetamide; more preferably, the low polar solvent nonafluorobutyl ethyl ether.

[0038] Preferably, the solid content of the photolithography flexible end paste resin composition is 10-90%, for example, it may be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, etc.

[0039] In the present invention, the solvent in the photolithography flexible end paste resin composition can be an externally added solvent, that is, the solvent is prepared with a solid aliphatic photosensitive resin and a solid fluorine-containing auxiliary resin to obtain a photolithography flexible end paste resin composition; it can also be a residual solvent from the process of preparing an aliphatic photosensitive resin and a fluorine-containing auxiliary resin.

[0040] Preferably, the auxiliary agent comprises a wetting agent and / or a leveling agent.

[0041] Preferably, the mass of the auxiliary agent in the photolithography flexible end paste resin composition is 0.1-5%, for example, it can be 0.1%, 0.2%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc.

[0042] In a second aspect, the present invention provides a method for preparing the photolithography flexible end paste resin composition according to the first aspect, the preparation method comprising the following steps:

[0043] The aliphatic photosensitive resin, the fluorine-containing auxiliary resin, and the optional solvent and auxiliary agent are mixed to obtain the photolithography flexible end paste resin composition.

[0044] Preferably, the preparation method of the aliphatic photosensitive resin comprises:

[0045] (1) mixing a monofunctional acrylate monomer with a first initiator and a solvent, and reacting the mixture at 70-76° C. (for example, 70° C., 72° C., 74° C., 76° C., etc.) for more than 1 hour (for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, etc.) to obtain a fluorine-containing epoxy acrylic resin;

[0046] (2) mixing the fluorinated epoxy acrylic resin obtained in step (1) with acrylic acid, a catalyst and a solvent, and reacting the mixture at 70-130° C. (for example, 70° C., 75° C., 80° C., 85° C., 90° C., 95° C., 100° C., 110° C., 120° C., 125° C., 130° C.) for more than 0.5 h (for example, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, etc.) to obtain the aliphatic photosensitive resin.

[0047] In the present invention, the solvent in step (1) includes nonafluorobutyl ether; the solvent in step (2) includes dimethylacetamide; the mass of the solvent in step (2) is 20-30% of the total mass of the system; the catalyst in step (2) includes at least one of triphenylphosphine and N,N-dimethylbenzylamine; the mass of the catalyst is 0.4-0.8% of the total mass of the fluorinated epoxy acrylic resin and acrylic acid, for example, it can be 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, etc.

[0048] Preferably, the preparation method of the fluorine-containing auxiliary resin comprises:

[0049] S1: Mix the monomer with the second initiator and the solvent, and react at 70-76°C (for example, 70°C, 72°C, 74°C, 76°C, etc.) for more than 1h (for example, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc.) to obtain a fluorine-containing auxiliary resin.

[0050] In the present invention, the solvent in step S1 includes nonafluorobutyl ethyl ether.

[0051] In a third aspect, the present invention provides a photolithography electronic conductive paste for electronic components, wherein the photolithography electronic conductive paste comprises the photolithography flexible end paste resin composition described in the first aspect.

[0052] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] The photolithography flexible end paste resin composition provided by the present invention adopts aliphatic photosensitive resin of specific structure and fluorine-containing auxiliary resin of specific structure to be compounded in specific content, so that the photolithography flexible end paste resin composition has suitable development time, good hole filling effect and wetting effect and excellent long-term ultraviolet aging resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is an infrared spectrum of the aliphatic photosensitive resin provided in Example 1 of the present invention.

[0056] Figure 2 This is the infrared spectrum of the fluorine-containing auxiliary resin provided in Example 1 of the present invention.

[0057] Figure 3 A gel permeation chromatography elution curve of the aliphatic photosensitive resin provided in Example 1 of the present invention;

[0058] Among them, curve 1 is the calibration curve of the standard sample polystyrene; curve 2 is the elution curve of the polymer; among them, peak 1 represents a polymer with a number average molecular weight of 1849; peak 2 represents a polymer with a number average molecular weight of 937; peak 3 represents a compound with a number average molecular weight of 274; peak 4 represents a compound with a number average molecular weight of 130.

[0059] Figure 4 This is a gel permeation chromatography elution curve of the fluorine-containing auxiliary resin provided in Example 1 of the present invention;

[0060] Among them, curve 1 is the calibration curve of the standard sample polystyrene; curve 2 is the elution curve of the polymer; among them, peak 1 represents a polymer with a number average molecular weight of 22811; peak 2 represents a polymer with a number average molecular weight of 3806; peak 3 represents a compound with a number average molecular weight of 234. DETAILED DESCRIPTION

[0061] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0062] Example 1

[0063] This embodiment provides a photolithography flexible end paste resin composition, which includes an aliphatic photosensitive resin and a fluorine-containing auxiliary resin in a mass ratio of 5:1.

[0064] The raw materials for preparing the aliphatic photosensitive resin include fluorinated epoxy acrylic resin and acrylic acid; the molar ratio of the acrylic acid to the epoxy group in the fluorinated epoxy acrylic resin is 1.12:1; the raw materials for preparing the fluorinated epoxy acrylic resin include monofunctional acrylate monomers and an initiator (AIBN, the mass of which is 1.5% of the total mass of the monofunctional acrylate monomers); the monofunctional acrylate monomers include methyl methacrylate, ethyl methacrylate, glycidyl methacrylate and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 25:12:2:8.5.

[0065] The raw materials for preparing the fluorine-containing auxiliary resin include monomers and an initiator (AIBN, the mass of which is 3.5% of the total mass of the monomers); the monomers include methyl methacrylate, styrene, methacrylic acid and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 25:12:2:8.5.

[0066] The photolithography flexible end paste resin composition further includes a solvent, a leveling agent (0.3% by mass of the photolithography flexible end paste resin composition, BYK-333) and a wetting agent (0.2% by mass of the photolithography flexible end paste resin composition, BASF EFKA® FL 3772).

[0067] This embodiment provides a method for preparing a photolithography flexible end paste resin composition, which specifically includes the following steps:

[0068] (1) 300 parts of monofunctional acrylate monomers are mixed with a formula amount of AIBN and 120 parts of low-polarity solvent nonafluorobutyl ether, and the mixture is reacted at 76°C for 8 hours to obtain a fluorinated epoxy acrylic resin; dimethylacetamide (25% by weight of the fluorinated epoxy acrylic resin) is added to the fluorinated epoxy acrylic resin, the solvent nonafluorobutyl ether is removed under vacuum, and then a formula amount of acrylic acid and triphenylphosphine (0.6% by weight of the total weight of the fluorinated epoxy acrylic resin and acrylic acid) are added, and the mixture is reacted at 110°C for 5 hours to obtain the aliphatic photosensitive resin;

[0069] (2) 300 parts of the monomers were mixed with the formulated amount of AIBN and 120 parts of nonafluorobutyl ether, and reacted at 76° C. for 5 hours to obtain a fluorine-containing auxiliary resin;

[0070] (3) According to the formula amount, the aliphatic photosensitive resin obtained in step (1), the fluorine-containing auxiliary resin obtained in step (2), a leveling agent and a wetting agent are mixed to obtain the photolithography flexible end paste resin composition; the solvent in the photolithography flexible end paste resin composition is the residual solvent of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin.

[0071] The structures of the aliphatic photosensitive resin obtained in step (1) and the fluorine-containing auxiliary resin obtained in step (2) were characterized by Fourier transform infrared spectroscopy. Figure 1 (Aliphatic photosensitive resin) and Figure 2 (fluorinated auxiliary resin) shown.

[0072] The number average molecular weight (Mn) of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin was characterized by gel permeation chromatography, and the elution curves obtained were as follows: Figure 3 (Aliphatic photosensitive resin) and Figure 4 (fluorinated auxiliary resin) shown.

[0073] Figure 3 In the figure, curve 1 is the calibration curve of the standard sample (polystyrene); curve 2 is the elution curve of the polymer; wherein peak 1 represents a polymer with a number average molecular weight of 1849; peak 2 represents a polymer with a number average molecular weight of 937; peak 3 represents a compound with a number average molecular weight of 274; and peak 4 represents a compound with a number average molecular weight of 130.

[0074] Figure 4 In the figure, curve 1 is the calibration curve of the standard sample (polystyrene); curve 2 is the elution curve of the polymer; wherein peak 1 represents a polymer with a number average molecular weight of 22811; peak 2 represents a polymer with a number average molecular weight of 3806; and peak 3 represents a compound with a number average molecular weight of 234.

[0075] Example 2

[0076] This embodiment provides a photolithography flexible end paste resin composition, which is different from Embodiment 1 in that the total mass of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin in the photolithography flexible end paste resin composition remains unchanged, and the mass ratio of the two is 4:1.

[0077] The raw materials for preparing the aliphatic photosensitive resin include fluorinated epoxy acrylic resin and acrylic acid; the molar ratio of the acrylic acid to the epoxy group in the fluorinated epoxy acrylic resin is 1.18:1; the raw materials for preparing the fluorinated epoxy acrylic resin include monofunctional acrylate monomers and an initiator (AIBN, the mass of which is 1.8% of the total mass of the monofunctional acrylate monomers); the total mass of the monofunctional acrylate monomers remains unchanged, and include methyl methacrylate, ethyl methacrylate, glycidyl methacrylate and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 22:14:1:10.

[0078] The raw materials for preparing the fluorine-containing auxiliary resin include monomers and an initiator (AIBN, the mass of which is 4% of the total mass of the monomers); the total mass of the monomers remains unchanged, and include methyl methacrylate, styrene, methacrylic acid and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 30:10:3:7; the other components, amounts used and preparation methods are the same as those in Example 1.

[0079] Example 3

[0080] This embodiment provides a photolithography flexible end paste resin composition, which is different from Embodiment 1 in that the total mass of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin in the photolithography flexible end paste resin composition remains unchanged, and the mass ratio of the two is 6:1.

[0081] The raw materials for preparing the aliphatic photosensitive resin include fluorinated epoxy acrylic resin and acrylic acid; the molar ratio of the acrylic acid to the epoxy group in the fluorinated epoxy acrylic resin is 1.05:1; the raw materials for preparing the fluorinated epoxy acrylic resin include monofunctional acrylate monomers and an initiator (AIBN, the mass of which is 1.3% of the total mass of the monofunctional acrylate monomers); the total mass of the monofunctional acrylate monomers remains unchanged, and include methyl methacrylate, ethyl methacrylate, glycidyl methacrylate and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 28:10.5:2.8:7.2.

[0082] The raw materials for preparing the fluorine-containing auxiliary resin include monomers and an initiator (AIBN, with a mass of 3.3% of the total mass of the monomers); the total mass of the monomers remains unchanged, and include methyl methacrylate, styrene, methacrylic acid and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in a mass ratio of 21:15:1:10; other components, amounts and preparation methods are the same as those in Example 1.

[0083] Example 4

[0084] This embodiment provides a photolithography flexible end paste resin composition, which differs from Example 1 only in that the content of acrylic acid in the aliphatic photosensitive resin is reduced so that the molar ratio of acrylic acid to the epoxy group in the fluorine-containing epoxy acrylic resin is 1.02:1, and the other components, amounts and preparation methods are the same as those in Example 1.

[0085] Example 5

[0086] This embodiment provides a photolithography flexible end paste resin composition, which is different from Example 1 only in that the content of acrylic acid is increased in the aliphatic photosensitive resin so that the molar ratio of acrylic acid to the epoxy group in the fluorine-containing epoxy acrylic resin is 1.3:1, and the other components, amounts and preparation methods are the same as those in Example 1.

[0087] Example 6

[0088] This embodiment provides a photolithography flexible end paste resin composition, which is different from Example 1 only in that in the aliphatic photosensitive resin, the total mass of methyl methacrylate, ethyl methacrylate, glycidyl methacrylate and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate remains unchanged, and the mass ratio is 12:25:5:5, and the other components, amounts, ratios and preparation methods are the same as those in Example 1.

[0089] Example 7

[0090] This embodiment provides a photolithography flexible end paste resin composition, which is different from Example 1 only in that in the aliphatic photosensitive resin, the total mass of methyl methacrylate, ethyl methacrylate, glycidyl methacrylate and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate remains unchanged, and the mass ratio is 35:5:0.5:12, and the other components, amounts, ratios and preparation methods are the same as those in Example 1.

[0091] Example 8

[0092] This embodiment provides a photolithography flexible end paste resin composition, which differs from Embodiment 1 only in that ethyl methacrylate in the aliphatic photosensitive resin is replaced with an equal mass of methyl methacrylate, and other components, amounts and preparation methods are the same as those in Embodiment 1.

[0093] Example 9

[0094] This embodiment provides a photolithography flexible end paste resin composition, which is different from Example 1 only in that in the fluorine-containing auxiliary resin, the total mass of methyl methacrylate, styrene, methacrylic acid and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate remains unchanged, and the mass ratio is 35:5:0.5:12. The other components, amounts and preparation methods are the same as those in Example 1.

[0095] Example 10

[0096] This embodiment provides a photolithography flexible end paste resin composition, which is different from Example 1 only in that in the fluorine-containing auxiliary resin, the total mass of methyl methacrylate, styrene, methacrylic acid and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate remains unchanged, and the mass ratio is 15:20:5:5. The other components, amounts and preparation methods are the same as those in Example 1.

[0097] Embodiment 11

[0098] This embodiment provides a photolithography flexible end paste resin composition, which differs from Embodiment 1 only in that methacrylic acid is replaced with acrylic acid of equal mass in the fluorine-containing auxiliary resin, and other components, amounts and preparation methods are the same as those in Embodiment 1.

[0099] Comparative Example 1

[0100] This comparative example provides a photolithography flexible end paste resin composition, which differs from Example 1 only in that the total mass of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin remains unchanged, and the mass ratio between the two is 2:1. Other components, amounts and preparation methods are the same as those in Example 1.

[0101] Comparative Example 2

[0102] This comparative example provides a photolithography flexible end paste resin composition, which differs from Example 1 only in that the total mass of the aliphatic photosensitive resin and the fluorine-containing auxiliary resin remains unchanged, and the mass ratio between the two is 8:1. Other components, amounts and preparation methods are the same as those in Example 1.

[0103] Comparative Example 3

[0104] This comparative example provides a photolithography flexible end paste resin composition, which differs from Example 1 only in that 1,1,1,3,3,3-hexafluoroisopropyl methacrylate in the raw materials for preparing the aliphatic photosensitive resin and the fluorine-containing auxiliary resin is replaced with an equal mass of isopropyl methacrylate, and the other components, amounts and preparation methods are the same as those in Example 1.

[0105] Comparative Example 4

[0106] This comparative example provides a photolithography flexible end paste resin composition, which differs from Example 1 only in that, in the aliphatic photosensitive resin, methyl methacrylate is replaced by an equal mass of phenyl methacrylate, and ethyl methacrylate is replaced by an equal mass of benzyl methacrylate, and other components, amounts and preparation methods are the same as those in Example 1.

[0107] Performance Testing

[0108] The photolithography flexible end paste resin compositions provided in Examples 1 to 11 and Comparative Examples 1 to 4 were subjected to the following performance tests.

[0109] (1) Hole filling effect and hole wetting effect: To prepare hole filling silver paste, the resin composition, conductive agent and photoinitiator are mixed in a mass ratio of 20:80:5 using a three-roll mill, and the environment needs to be in the yellow light zone; wherein the conductive agent is silver powder with a D95 of 10 μm, and the photoinitiator is ITX (2-isopropylthioxanthone); the three-roll mill has an inlet roller spacing of 30 μm and an outlet roller spacing of 10 μm, and the mixture is repeatedly mixed for 40 min until the slurry is uniform, thus obtaining the hole filling silver paste; then the hole filling silver paste is used to print on the substrate; the printed substrate is a substrate with holes, the hole diameter is about 40 μm, and the depth is 0. 5mm; after printing, it was baked at 80℃ for 30min, exposed to UV light, and then developed in a 0.4wt% sodium carbonate aqueous solution for 60s, and the filling of silver paste in the hole was observed under a 400x microscope; among them, the silver paste filling degree was 100% (that is, the entire hole was filled with silver paste), marked as "0", indicating that the filling effect was good, and the hole filling effect and hole wetting effect were good; the silver paste filling degree was 50-100% (not including 100%), marked as "1", indicating that the filling effect was second; the silver paste filling degree was less than 50%, marked as "2", indicating that the filling effect was poor.

[0110] (2) Long-term UV aging resistance: The mass ratio of the resin composition to the photoinitiator is 100:6, and ITX is selected as the initiator. The resin composition and ITX are mixed evenly, and then coated on a white ceramic sheet. The same process as in (1) is used for baking and development to form a resin dry film on the white ceramic sheet. The dry film thickness is about 30 μm. The long-term UV aging resistance of the dry film is tested.

[0111] The test reference standard is GB / T 16422.3-2014, fluorescent ultraviolet lamp (lamp model UVB-313, light intensity 40W / m, 8 320W lamps in total; wavelength 280nm~400nm). The ceramic sheet is fixed on the test frame in a way that it is not subjected to any external stress. The irradiation surface is the preparation material surface (i.e., dry film surface). It is irradiated for 4 hours at a temperature of 60℃±2℃, and then stopped for 4 hours (darkness). 8 hours is one cycle. After 3 cycles and 24 hours, the color difference △E before and after is measured. The color difference is required to be less than 1.5;

[0112] (3) Development time: Prepare silver paste in the same manner as in (1), apply it on a white ceramic sheet and dry it, then expose it using a musical note-shaped exposure pattern, and develop it in a 0.4 wt% sodium carbonate aqueous solution. Observe the time it takes for the pattern to reach a clear musical note shape after development. The optimal time is 45-60 seconds.

[0113] The specific test results are shown in Table 1.

[0114] Table 1

[0115]

[0116] As can be seen from Table 1, the photolithography flexible end paste resin composition provided by the present invention adopts a specific structure of aliphatic photosensitive resin and a specific structure of fluorine-containing auxiliary resin compounded in a specific content, so that the photolithography flexible end paste resin composition has a suitable development time, good hole filling effect and wetting effect and excellent long-term ultraviolet aging resistance; the hole filling filling degree is greater than 50%, and can even reach 100%; △E≤1.2, and the development time is suitable.

[0117] In Comparative Examples 1 and 2, the ratio of auxiliary resin to photosensitive resin exceeds a reasonable range, which will result in a development time that is too short or too long; in Comparative Example 3, a fluorine-free monomer is used instead of a fluorine-containing monomer, resulting in a very poor filling effect; and in Comparative Example 4, due to the large difference in monomer structure and completely different main chain segment performance, the filling effect is also poor. At the same time, due to the aromatic group, the UV aging effect is also poor.

[0118] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A photolithography flexible end paste resin composition, characterized in that: The photolithography flexible end paste resin composition comprises an aliphatic photosensitive resin and a fluorine-containing auxiliary resin; The molecular structure of the aliphatic photosensitive resin contains a carbon-carbon double bond; the molecular structure of the fluorine-containing auxiliary resin contains a carboxyl group; The mass ratio of the aliphatic photosensitive resin to the fluorine-containing auxiliary resin is (4-6):

1.

2. The photolithography flexible end paste resin composition according to claim 1, characterized in that: The raw materials for preparing the aliphatic photosensitive resin include fluorine-containing epoxy acrylic resin and acrylic acid.

3. The photolithography flexible end paste resin composition according to claim 2, characterized in that: The molar ratio of the acrylic acid to the epoxy group in the fluorinated epoxy acrylic resin is (1.05-1.2):

1.

4. The photolithography flexible end paste resin composition according to claim 3, characterized in that: The raw materials for preparing the fluorine-containing epoxy acrylic resin include monofunctional acrylate monomers and a first initiator; The monofunctional acrylate monomer includes a first C1-C6 alkyl acrylate, an epoxy acrylate and a first fluorine-containing acrylate; The mass ratio of the first C1-C6 alkyl acrylate, epoxy acrylate and first fluorine-containing acrylate is (30-45):(1-3):(7-10); The mass of the first initiator is 1.3-2% of the total mass of the monofunctional acrylate monomer.

5. The photolithography flexible end paste resin composition according to claim 4, characterized in that: The first C1-C6 alkyl acrylate includes at least one of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-propyl methacrylate, n-propyl acrylate, isopropyl methacrylate, isopropyl acrylate, n-butyl methacrylate or n-butyl acrylate; The epoxy acrylate includes glycidyl methacrylate; All H atoms on at least two carbon atoms in the first fluorine-containing acrylate are replaced by F atoms.

6. The photolithography flexible end paste resin composition according to claim 5, characterized in that: The first fluorine-containing acrylate includes 1,1,1,3,3,3-hexafluoroisopropyl methacrylate; The raw materials for preparing the fluorine-containing auxiliary resin include monomers and a second initiator; The monomers include a second C1-C6 alkyl acrylate, a styrene monomer, methacrylic acid, and a second fluorine-containing acrylate; The mass ratio of the second C1-C6 alkyl acrylate, the styrene monomer, methacrylic acid and the second fluorinated acrylate is (20-30):(10-15):(1-3):(7-10); The mass of the second initiator is 3.3-4.2% of the total mass of the monomers.

7. The photolithography flexible end paste resin composition according to claim 6, characterized in that: The second C1-C6 alkyl acrylate includes at least one of methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-propyl methacrylate, n-propyl acrylate, isopropyl methacrylate, isopropyl acrylate, n-butyl methacrylate or n-butyl acrylate; In the second fluorine-containing acrylate, H atoms on at least two carbon atoms are all replaced by F atoms.

8. The photolithography flexible end paste resin composition according to claim 7, characterized in that: The second fluorine-containing acrylate includes 1,1,1,3,3,3-hexafluoroisopropyl methacrylate; The photolithography flexible end paste resin composition further comprises a solvent and / or an auxiliary agent; The solvent includes nonafluorobutyl ether and / or dimethylacetamide; The solid content of the photolithography flexible end paste resin composition is 10-90%; The auxiliary agent includes a wetting agent and / or a leveling agent; The mass of the auxiliary agent in the photolithography flexible end paste resin composition is 0.1-5%.

9. A method for preparing a photolithography flexible end paste resin composition according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: Mixing an aliphatic photosensitive resin, a fluorine-containing auxiliary resin, and optional solvents and additives to obtain the photolithography flexible end paste resin composition; The preparation method of the aliphatic photosensitive resin comprises: (1) mixing a monofunctional acrylate monomer with a first initiator and a solvent, and reacting the mixture at 70-76° C. for more than 1 hour to obtain a fluorinated epoxy acrylic resin; (2) mixing the fluorinated epoxy acrylic resin obtained in step (1) with acrylic acid, a catalyst and a solvent, and reacting the mixture at 70 to 130° C. for more than 0.5 h to obtain the aliphatic photosensitive resin; The preparation method of the fluorine-containing auxiliary resin comprises: S1: Mix the monomer, the second initiator and the solvent, and react at 70-76° C. for more than 1 hour to obtain the fluorine-containing auxiliary resin.

10. A photolithography electronic conductive paste for electronic components, characterized in that: The photolithography electronic conductive paste comprises the photolithography flexible end paste resin composition according to any one of claims 1 to 8.

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