High-heat-resistant yellowing-resistant chemical corrosion-resistant negative photosensitive resin

Abstract

The application discloses a high-heat-yellowing-resistance and chemical-corrosion-resistance negative photosensitive resin, which is used for the insulating layer between electrodes or the covering layer of RGB color resist in a liquid crystal panel and comprises an alkali-soluble acrylic copolymer, an ethylenic unsaturated double bond monomer, a photoinitiator, a solvent and an epoxy crosslinking agent. The negative photosensitive resin obtained by the application can form the insulating layer between electrodes or the covering layer of RGB color resist in the liquid crystal panel and has excellent heat-yellowing resistance and chemical corrosion resistance.

Description

Technical Field

[0001] This invention belongs to the field of photoresist mask technology, and particularly relates to a negative photosensitive resin with good heat resistance to yellowing and chemical corrosion resistance. Background Technology

[0002] In the current COA (color filter on array) process of TFT-LCD (Thin film transistor liquid crystal display) panels, photosensitive resin compositions are typically used as organic insulating films to fill the gaps between RGB color resists and to cover the metal electrodes. Therefore, this photosensitive resin composition requires a high light transmittance of the underlying RGB color resists, meaning it needs high transmittance for visible light wavelengths. Considering the subsequent ITO sputtering and wet etching processes, the organic insulating film also needs to have high resistance to chemical corrosion.

[0003] However, resin compositions commonly used in organic insulating films do not exhibit excellent heat resistance and yellowing resistance, and poor array substrate yield can occur in COA processes due to poor chemical corrosion resistance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a negative photosensitive resin with high heat resistance to yellowing and chemical corrosion resistance, exhibiting excellent heat resistance to yellowing and chemical corrosion resistance.

[0005] To achieve the above technical objectives, the present invention adopts the following technical solution: a negative photosensitive resin with high heat resistance, yellowing resistance, and chemical corrosion resistance, used as an insulating layer between electrodes or a covering layer for RGB color resists in a liquid crystal panel, comprising the following components in parts by weight: 100 parts of alkali-soluble acrylic copolymer Contains 10-200 parts of vinyl unsaturated double bond monomers 1-50 parts of photoinitiator Solvent 50-400 parts 8-35 parts of epoxy crosslinking agent 0-10 parts of additives The epoxy crosslinking agent has the following general chemical formula (Ⅰ). (I) In the above general chemical formula, R1, R2, and R3 are each C1 to C12 alkylene groups.

[0006] Preferably, the additive is a silane coupling agent and / or a surfactant.

[0007] Preferably, the weight-average molecular weight of the alkali-soluble acrylic acid copolymer is 5000-20000 when converted to polystyrene, and the acid value is 30-200 mg / g.

[0008] Preferably, the monomer containing ethylene unsaturated double bonds is a compound having two or more (meth)acryloyl groups.

[0009] Preferably, the monomer containing the ethylene unsaturated double bond is ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerol di(meth)acrylate, tripropylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1, 10-Decanediol di(meth)acrylate; one or more of the following: glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, tetrapentaerythritol nona(meth)acrylate, tetrapentaerythritol deca(meth)acrylate, pentapentaerythritol undeca(meth)acrylate, and pentapentaerythritol dodeca(meth)acrylate.

[0010] Furthermore, the components and contents of the aforementioned high heat resistance, yellowing resistance, and chemical corrosion resistance negative photosensitive resin are as follows: 100 parts of acrylic copolymer Dipentaerythritol hexaacrylate (DPHA) 24 parts 8 parts of photoinitiator 350 parts of methyl 3-methoxypropionate 16 parts of triglycidyl isocyanurate 1 part of silane coupling agent 1 part surfactant.

[0011] Beneficial effects: Compared with the prior art, the present invention obtains a negative photosensitive resin with superior heat resistance and chemical corrosion resistance by screening the ratio of acrylic acid copolymer, monomer containing ethylene unsaturated double bond, photoinitiator (c), solvent (d) and specific epoxy crosslinking agent, and by exploring the optimal content of each component. Detailed Implementation

[0012] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0013] The present invention proposes a negative photosensitive resin with high heat resistance, yellowing resistance and chemical corrosion resistance, which is used as an insulating layer between electrodes or a cover layer for RGB color resist in liquid crystal panels. It has excellent heat resistance, yellowing resistance and chemical corrosion resistance. It includes an alkali-soluble acrylic copolymer (a), a monomer containing ethylene unsaturated double bonds (b), a photoinitiator (c), a solvent (d), and an epoxy crosslinking agent of the following chemical formula 1 (e).

[0014] [Chemical Formula 1]

[0015] In the above chemical formula, R1, R2, and R3 are each a C1-C12 alkylene group. Preferably, the above negative photosensitive resin composition is characterized by comprising: a) 100 parts by weight of acrylic copolymer b) Contains 10-200 parts by weight of monomers with ethylene-unsaturated double bonds. c) 1-50 parts by weight of photoinitiator d) Solvent 50~400 parts by weight e) 8 to 30 parts by weight of the epoxy crosslinking agent of the above chemical formula 1.

[0016] The composition, preparation method, and application performance of the negative photosensitive resin of the present invention are described in detail below through specific embodiments and comparative examples. Example 1

[0017] Depending on the physical properties required for actual production, the negative photosensitive resin composition of the present invention may also contain some known conventional additives. Preferably, the additives may be silane coupling agents and surfactants.

[0018] The preparation process is as follows: 100 parts of acrylic copolymer (weight average molecular weight Mw 8700, acid value 86 mg / g), 24 parts of dipentaerythritol hexaacrylate (DPHA), 8 parts of photoinitiator (OXE01), 16 parts of epoxy crosslinking agent (TGIC), 1 part of silane coupling agent, and 1 part of surfactant are mixed in proportion, and then 350 parts of methyl 3-methoxypropionate solvent are added and stirred to dissolve, thus obtaining the corresponding negative photosensitive resin composition. The photoinitiator used is 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime) (OXE01) manufactured by BASF, and the epoxy crosslinking agent used is triglycidyl isocyanate TGIC.

[0019] Example 2-10 The difference between this embodiment and the previous embodiment lies in the different types and amounts of components, as detailed in Table 1.

[0020] Table 1. Content of each component in various embodiments of the present invention

[0021] Then, the evaluation is conducted through the following steps and methods: Photoresist film and development experiments: A resin composition was spin-coated onto a glass plate, followed by low-pressure evacuation to remove most of the solvent. The plate was then baked on a hot plate at 100 °C for 90 s to obtain a photoresist film approximately 3 μm thick. The glass plate covered with the photoresist film was exposed to an exposure dose of 50 mJ / cm², then developed with a 2.48% tetramethylammonium hydroxide aqueous solution for 90 s. It was then rinsed with ultrapure water and baked in a 230 °C oven for 30 min to obtain a photoresist glass sheet with the corresponding pattern.

[0022] Heat resistance and yellowing test: The above-mentioned photoresist glass sheet was baked in an oven at 250 °C for 1 hour, and then its transmittance at a wavelength of 400 nm was measured. Transmittance greater than 96% is indicated by "○", transmittance between 90 and 96% is indicated by "△", and transmittance less than 90% is indicated by "×".

[0023] Chemical corrosion resistance test: The above-mentioned patternless photoresist glass slide was marked with a cross-cut pattern using a cross-cutting tool. Then, it was placed in propylene glycol methyl ether acetate (PGMEA), N-methylpyrrolidone (NMP), 1% oxalic acid aqueous solution (acidic aqueous solution), and diethylene glycol monobutyl ether solution containing 10% triethanolamine (alkaline organic solution) for 10 min respectively. After that, it was taken out, rinsed with ultrapure water, and dried. The film layer was then treated with 3M tape according to the cross-cut pattern test and classified into ATSM grades.

[0024] Table 2 shows the performance test results for each embodiment.

[0025] Table 2 shows that, with the addition of TGIC as an epoxy crosslinking agent, the photosensitive resin composition exhibits superior heat resistance and chemical corrosion resistance compared to general epoxy crosslinking agent (GMA) photosensitive resin compositions or those obtained without epoxy crosslinking agents. Furthermore, when the TGIC addition amount is in the range of 8-30 parts by weight, the photosensitive resin film demonstrates optimal 400nm transmittance, heat resistance, and corrosion resistance. When the addition amount is less than 8 parts, the film's heat resistance and chemical corrosion resistance decrease sharply; when the addition amount is greater than 30 parts, scum appears during the resin development process, leading to unclear patterns after development, and the chemical corrosion resistance and yellowing resistance also decrease significantly.

[0026] In this embodiment of the invention, the weight-average molecular weight (Mw) of the acrylic copolymer is 8700 and the acid value is 86 mg / g. Excessively high polymer molecular weight will lead to a significant decrease in the light transmittance, heat resistance, yellowing resistance, and corrosion resistance of the product resin film. Through experiments, the weight-average molecular weight (Mw) of the acrylic copolymer is preferably between 5000 and 20000.

[0027] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A negative photosensitive resin with high heat resistance, yellowing resistance, and chemical corrosion resistance, used as an insulating layer between electrodes or a covering layer for RGB color resists in a liquid crystal panel, characterized in that... Composed of the following components in parts by weight composition: 100 parts of alkali-soluble acrylic copolymer Contains 10-200 parts of vinyl unsaturated double bond monomers 1-50 parts of photoinitiator Solvent 50-400 parts 8-30 parts of epoxy crosslinking agent Functional additives 0-10 parts The epoxy crosslinking agent has the following general chemical formula (Ⅰ). （Ⅰ） In the above general chemical formula, R1, R2, and R3 are each a C1 to C12 alkylene group; The weight-average molecular weight of the alkali-soluble acrylic acid copolymer is 5000-20000 when converted to polystyrene, and the acid value is 30-200 mg / g. The monomer containing the vinyl unsaturated double bond is selected from dipentaerythritol hexaacrylate.

2. The high heat resistance, yellowing resistance, and chemical corrosion resistance negative photosensitive resin according to claim 1, characterized in that: The functional additives are silane coupling agents and / or surfactants.

3. The high heat resistance, yellowing resistance, and chemical corrosion resistance negative photosensitive resin according to claim 1, characterized in that: The components and their contents are as follows: 100 parts of alkali-soluble acrylic copolymer Dipentaerythritol hexaacrylate (DPHA) 24 parts 8 parts of photoinitiator Solvent: methyl 3-methoxypropionate 350 parts 16 parts of epoxy crosslinking agent triglycidyl isocyanate 1 part silane coupling agent 1 part surfactant.

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