Photosensitive resin composition, and dry film photoresist and preparing method therefor, resist pattern, and display device each using same

Abstract

The present invention relates to a photosensitive resin composition, and a dry film photoresist and a preparing method therefor, a resist pattern, and a display device each using same, wherein the composition is capable of forming fine patterns even in a 120-μm thick coating film and achieving excellent adhesion, resolution, rigidity, and chemical resistance.

Description

Photosensitive resin composition, dry film photoresist using the same, method for manufacturing the same, resist pattern, and display device

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0133318 dated September 30, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003] The present invention relates to a photosensitive resin composition, a dry film photoresist using the same, a method for manufacturing the same, a resist pattern, and a display device.

[0004] Photosensitive resin compositions are used in the form of dry film photoresist (DFR) and liquid photoresist ink, which are used in printed circuit boards (PCBs) or lead frames.

[0005] Currently, dry film photoresist is widely used not only for manufacturing printed circuit boards (PCBs) and lead frames, but also for manufacturing rib barriers of plasma display panels (PDPs), ITO electrodes, bus address electrodes, and black matrices of other displays.

[0006] Generally, such dry film photoresists are widely used for lamination onto copper clad laminates. In this regard, as an example of the manufacturing process for a Printed Circuit Board (PCB), a pretreatment process is first performed to laminate the copper clad laminate, which serves as the base material for the PCB. The pretreatment process for the outer layer involves drilling, deburring, and face-off in that order, while the inner layer process involves face-off or pickling. Bristle brushes and jet pumice are mainly used for the face-off process, and pickling may involve soft etching and 5 wt% sulfuric acid pickling.

[0007] In order to form a circuit on a copper laminate that has undergone a pretreatment process, a dry film photoresist (hereinafter referred to as DFR) is generally laminated onto the copper layer of the copper laminate. In this process, a laminator is used to remove the protective film of the DFR while laminating the photoresist layer of the DFR onto the copper surface. Generally, the process is carried out at a lamination speed of 0.5 to 3.5 m / min, a temperature of 100 to 130°C, and a roller pressure of 10 to 90 psi.

[0008] After the printed circuit board has undergone the lamination process, it is left for at least 15 minutes to stabilize the substrate, and then exposure is performed on the photoresist of the DFR using a photomask with a desired circuit pattern formed thereon. During this process, when ultraviolet light is irradiated onto the photomask, polymerization is initiated in the irradiated photoresist by the photoinitiator contained in the irradiated area. Initially, oxygen within the photoresist is consumed, followed by the polymerization of activated monomers to undergo a cross-linking reaction, and subsequently, the polymerization reaction proceeds as a large amount of monomer is consumed. Meanwhile, the unexposed area remains in a state where the cross-linking reaction has not taken place.

[0009] Next, a development process is performed to remove unexposed portions of the photoresist. In the case of an alkaline developable DFR, an aqueous solution of 0.8 to 1.2 wt% potassium carbonate and sodium carbonate is used as the developer. In this process, the photoresist in the unexposed portions is washed away by the saponification reaction between the carboxylic acid of the binder polymer and the developer within the developer, and the cured photoresist remains on the copper surface.

[0010] A circuit is formed through different processes according to the following inner and outer layer processes. In the inner layer process, a circuit is formed on the substrate through etching and stripping processes, and in the outer layer process, after undergoing plating and tenting processes, etching and solder stripping are performed to form a predetermined circuit.

[0011] Generally, a pattern is formed using a photosensitive resin composition comprising an epoxy resin such as an alkali-developable binder resin or bisphenol A novolac resin, a photopolymerization initiator, and a photopolymerizable compound.

[0012] However, conventional technology has a limit of 8 / 15 μm in the resolution pitch of the line width / line spacing of the resist pattern based on a 120 μm film, so photolithography using conventional photosensitive resin compositions has shown limitations in forming fine patterns of 8 / 15 μm or less.

[0013] Therefore, it is necessary to develop a photosensitive resin composition that enables the formation of fine patterns while also possessing excellent physical properties such as rigidity and chemical resistance.

[0014]

[0015] The present invention aims to provide a photosensitive resin composition capable of forming fine patterns even on thick films based on a 120㎛ film thickness, and capable of achieving excellent adhesion, resolution, rigidity, and chemical resistance.

[0016] In addition, the present invention is intended to provide a dry film photoresist, a resist pattern, and a display device using the above-described photosensitive resin composition.

[0017]

[0018] The present specification provides a photosensitive resin composition comprising: an epoxy resin; a cationic initiator containing a sulfonium complex salt; and a plasticizer; wherein the plasticizer comprises an alkyl group represented by the following chemical formula 1.

[0019] [Chemical Formula 1]

[0020]

[0021] In the above chemical formula 1, R1 is hydrogen or an alkyl group having 2 or more carbon atoms, and R2 is hydrogen or an alkyl group having 1 or more carbon atoms.

[0022] In addition to the above, a dry film photoresist is provided, comprising a photosensitive resin layer containing the photosensitive resin composition.

[0023] The present specification also provides a method for manufacturing a dry film photoresist, comprising the step of coating the photosensitive resin composition on a polymer substrate.

[0024] In addition to the above, a resist pattern is provided, comprising a photosensitive resin pattern containing the photosensitive resin composition.

[0025] The present specification also provides a display device comprising the resist pattern or a metal pattern formed by the resist pattern.

[0026]

[0027] A photosensitive resin composition according to a specific embodiment of the invention, a dry film photoresist, a resist pattern, and a display device using the same will be described in more detail below.

[0028] Prior to that, unless explicitly stated otherwise in this specification, technical terms are used merely to refer to specific embodiments and are not intended to limit the invention.

[0029] The singular forms used in this specification include plural forms unless the phrases clearly indicate otherwise.

[0030] As used in this specification, the meaning of 'includes' specifies certain characteristics, regions, integers, steps, actions, elements, and / or components, and does not exclude the existence or addition of other specific characteristics, regions, integers, steps, actions, elements, components, and / or groups.

[0031] In this specification, the weight-average molecular weight refers to the weight-average molecular weight equivalent to polystyrene measured by the GPC method. In the process of measuring the weight-average molecular weight equivalent to polystyrene measured by the GPC method, commonly known analytical devices, detectors such as a refractive index detector, and analytical columns may be used, and commonly applied temperature conditions, solvents, and flow rates may be applied.

[0032] As a specific example of the above measurement conditions, an epoxy binder resin was dissolved in tetrahydrofuran to a concentration of 1.0 (w / w)% in THF (approx. 0.5 (w / w)% based on solid content), filtered using a 0.45㎛ pore size syringe filter, and 20㎛ was injected into the GPC. The mobile phase of the GPC was tetrahydrofuran (THF), introduced at a flow rate of 1.0 mL / min, and the column consisted of one Agilent PLgel 5㎛ Guard (7.5 x 50 mm) and two Agilent PLgel 5㎛ Mixed D (7.5 x 300 mm) connected in series. The measurement was performed at 40℃ using an Agilent 1260 Infinity II System RI Detector.

[0033] The weight-average molecular weight (Mw) of the epoxy binder resin was determined using a calibration curve formed by injecting polystyrene standard samples (STD A, B, C, D), in which polystyrene with various molecular weights as shown below was dissolved in tetrahydrofuran at a concentration of 0.1 (w / w)%, into a GPC after filtering through a 0.45㎛ pore size syringe filter.

[0034] STD A (Mp): 791,000 / 27,810 / 945

[0035] STD B (Mp): 282,000 / 10,700 / 580

[0036] STD C (Mp): 126,000 / 4,430 / 370

[0037] ST D (Mp): 51,200 / 1,920 / 162

[0038]

[0039] The present invention will be described in detail below.

[0040]

[0041] According to one embodiment of the invention, a photosensitive resin composition may be provided, comprising: an epoxy resin; a cationic initiator containing a sulfonium complex salt; and a plasticizer; wherein the plasticizer comprises an alkyl group represented by Formula 1.

[0042] The above photosensitive resin composition is a curable composition including an epoxy resin, and by introducing a UV absorber together with a specific plasticizer, a cationic initiator, and the epoxy resin, it is possible to achieve fine pitch circuit properties.

[0043] The inventors of the present invention confirmed through experiments that by including a plasticizer of a specific structure, the rigidity within the coating film is lowered and flexibility is increased, thereby enabling improvements in process yield and processability by preventing film cracking during the process.

[0044] In addition, the present invention can achieve fine pitch in thick films by introducing a specific cation initiator with low reactivity, and can achieve fine pitch with a stable profile by introducing multi-functional epoxy into the epoxy resin composition to improve the rigidity, chemical resistance, and coefficient of thermal expansion of the fine circuit line width.

[0045] Since the above photosensitive resin composition has circuit properties of fine pitch compared to conventional technology, it is possible to implement a fine pitch with a resolution of 20 µm or less based on a 120 µm coating film.

[0046] In addition, the above photosensitive resin composition can be applied to various display devices, but is particularly suitable for use in the barrier plating method of power inductors and can be applied as a material required for energy efficiency and precision technology.

[0047]

[0048] Hereinafter, each component of the photosensitive resin composition of the present invention will be described in more detail.

[0049]

[0050] The photosensitive resin composition of the above embodiment may include a plasticizer. Specifically, the plasticizer may include an alkyl group represented by the following chemical formula 1.

[0051] [Chemical Formula 1]

[0052]

[0053] In the above chemical formula 1, R1 is hydrogen or an alkyl group having 2 or more carbon atoms, and R2 is hydrogen or an alkyl group having 1 or more carbon atoms.

[0054]

[0055] As the photosensitive resin composition of the above embodiment includes a plasticizer comprising an alkyl group represented by Chemical Formula 1, the rigidity within the coating film is lowered and flexibility is increased, thereby enabling improvements in process yield and processability due to coating film cracking during the process.

[0056]

[0057] The above plasticizer may include one or more plasticizers selected from the group consisting of, for example, triethylene glycol bis(2-ethylhexanoate), di-2-ethylhexyl terephthalate, di-isononyl cyclohexane-1,2-dicarboxylate, and di-isononyl adipate.

[0058]

[0059] More specifically, the plasticizer may include a polyethylene glycol ester compound. For example, the plasticizer may include triethylene glycol bis(2-ethylhexanoate).

[0060]

[0061] The photosensitive resin composition of the above embodiment may include the plasticizer in an amount of 0.1 parts by weight or more and 5.0 parts by weight or less per 100 parts by weight of the epoxy resin.

[0062] Specifically, the photosensitive resin composition of the above embodiment may include the plasticizer in an amount of 0.1 parts by weight or more, 0.3 parts by weight or more, 0.5 parts by weight or more, 5.0 parts by weight or less, 2.5 parts by weight or less, 0.1 parts by weight or more and 5.0 parts by weight or less, 0.3 parts by weight or more and 5.0 parts by weight or less, 0.5 parts by weight or more and 5.0 parts by weight or less, 0.1 parts by weight or more and 2.5 parts by weight or less, 0.3 parts by weight or more and 2.5 parts by weight or less, and 0.5 parts by weight or more and 2.5 parts by weight or less, based on 100 parts by weight of the epoxy resin.

[0063] If the photosensitive resin composition of the above embodiment contains less than 0.1 parts by weight of the plasticizer per 100 parts by weight of the epoxy resin, technical problems such as reduced yield and reduced processability may occur due to film breakage during the process caused by insufficient flexibility in the film, and if it contains more than 5.0 parts by weight, technical problems such as contamination due to surface tackiness may occur due to a decrease in the glass transition temperature.

[0064]

[0065] In addition, the photosensitive resin composition of the above embodiment may contain the plasticizer in an amount of 50 parts by weight or more and 400 parts by weight or less per 100 parts by weight of the cation initiator.

[0066] Specifically, the photosensitive resin composition of the above embodiment may include the plasticizer in an amount of 50 parts by weight or more, 75 parts by weight or more, 80 parts by weight or more, 400 parts by weight or less, or 350 parts by weight or less, or 50 parts by weight or more and 400 parts by weight or less, 75 parts by weight or more and 400 parts by weight or less, 80 parts by weight or more and 400 parts by weight or less, 50 parts by weight or more and 350 parts by weight or less, 75 parts by weight or more and 350 parts by weight or less, or 80 parts by weight or more and 350 parts by weight or less, based on 100 parts by weight of the cationic initiator.

[0067] If the photosensitive resin composition of the above embodiment contains less than 50 parts by weight of the plasticizer per 100 parts by weight of the cation initiator, the processability may be poor due to increased rigidity and decreased flexibility within the film, and if the plasticizer contains more than 400 parts by weight of the plasticizer per 100 parts by weight of the cation initiator, problems such as reduced circuit resolution and the occurrence of non-development may occur due to the solvent effect caused by the increase in liquid components.

[0068]

[0069] The photosensitive resin composition of the above embodiment may include a cationic initiator containing a sulfonium complex salt. The cationic initiator refers to a cationic polymerization initiator that generates cationic species upon irradiation such as UV and active energy rays, and plays an important role in the curing of dry film photoresist. Accordingly, the cationic initiator is characterized by using a material that includes the function of a photo-generating agent with low reactivity while having sufficient performance to cure the epoxy resin, thereby enabling the formation of a fine pattern (i.e., fine pitch) in a thick film.

[0070] According to one embodiment of the invention, the cation initiator containing the sulfonium complex salt is thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium) bis tetrakis(pentafluorophenyl) borate (PAG-TR-21608), thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium) hexafluorophosphate, triarylsulfonium bis tetrakis(pentafluorophenyl) borate, triarylsulfonium hexafluorophosphate, 4-{[4-(diphenylsulfonium)phenyl]sulfanyl}phenyl)diphenylsulfonium) hexafluorophosphate (4-{[4-(diphenyl sulfonium)phenyl]sulfanyl}phenyl)diphenylsulfonium) It may be one or more selected from the group consisting of hexafluorophosphate (TR-PAG-202S). Preferably, it may be thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium)bistetrakis(pentafluorophenyl)borate.

[0071] The above specific type of cation initiator enables the maintenance of a high aspect ratio of 1:20 or higher even in thick films with a film thickness of 120㎛ without the Halation phenomenon due to low reactivity.

[0072]

[0073] Specifically, the photosensitive resin composition of the above embodiment may contain the cationic initiator in an amount of 0.1 parts by weight or more and 5.0 parts by weight or less per 100 parts by weight of the epoxy resin.

[0074] Specifically, the photosensitive resin composition of the above embodiment may include the cationic initiator in an amount of 0.1 parts by weight or more, 0.5 parts by weight or more, or 5.0 parts by weight or less, 3.0 parts by weight or less, 2.5 parts by weight or less, 1.0 parts by weight or less, or 0.1 parts by weight or more and 5.0 parts by weight or less, 0.1 parts by weight or more and 3.0 parts by weight or less, 0.1 parts by weight or more and 2.5 parts by weight or less, 0.1 parts by weight or more and 1.0 parts by weight or less, 0.5 parts by weight or more and 5.0 parts by weight or less, 0.5 parts by weight or more and 3.0 parts by weight or less, 0.5 parts by weight or more and 2.5 parts by weight or less, or 0.5 parts by weight or more and 1.0 parts by weight or less, based on 100 parts by weight of the epoxy resin.

[0075] If the content of the above-mentioned cationic initiator is less than 0.1 parts by weight, the degree of polymerization becomes insufficient, and circuit loss problems occur due to reduced solvent resistance and chemical resistance, and if the content exceeds 5.0 parts by weight, the realization of fine circuit patterns may be reduced due to line width expansion caused by overpolymerization of the photosensitive resin composition.

[0076]

[0077] The photosensitive resin composition of the above embodiment may include an epoxy resin.

[0078] The above epoxy resin may include three or more different types of epoxy resins, including a first epoxy resin, a second epoxy resin, and a third epoxy resin. The above epoxy resin includes at least three types of epoxy resins, and these at least three types of epoxy resins are each different from one another. Thus, three or more different types of epoxy resins may include a first epoxy resin, a second epoxy resin, and a third epoxy resin. The first epoxy resin, the second epoxy resin, and the third epoxy resin have different molecular structures.

[0079] The above three or more different types of epoxy resins may each independently have a softening point of 60°C to 105°C, 60°C to 102°C, 60°C to 85°C, or 60°C to 75°C. The softening point refers to the temperature at which deformation proceeds to a certain extent when an object such as a polymer resin is heated, and is measured for the purpose of determining what is the appropriate temperature for molding the polymer resin. Examples of methods for measuring the softening point are not significantly limited, and conventional methods for measuring the softening point of polymer resins may be applied without limitation. However, as an example, the softening point may be measured according to the standard of ASTM E 28-14.

[0080] That is, each of the first epoxy resin, the second epoxy resin, and the third epoxy resin may have a softening point of 60°C to 105°C, 60°C to 102°C, 60°C to 85°C, or 60°C to 75°C.

[0081] If the softening point of the three or more different types of epoxy resins mentioned above is excessively reduced independently, a problem may occur in which the photosensitive resin layer comes into contact with the exposure equipment during the exposure process, which is essential for pattern formation using the photosensitive resin composition, and the sticky, uncured photosensitive resin layer adheres to the exposure equipment, contaminating the exposure equipment.

[0082] On the other hand, if the softening point of the three or more different types of epoxy resins mentioned above increases excessively independently, the resolution may be reduced when forming a pattern using a photosensitive resin composition, making it difficult to implement fine patterns.

[0083] More specifically, the first epoxy resin may have a softening point of 60°C to 85°C, or 60°C to 70°C, or 75°C to 85°C. On the other hand, if the softening point of the first epoxy resin is reduced to less than 60°C, a problem may occur in which the photosensitive resin layer comes into contact with the exposure equipment during the exposure process, which is essential for pattern formation using the photosensitive resin composition, and the sticky, uncured photosensitive resin layer adheres to the exposure equipment, contaminating the exposure equipment. In addition, if the softening point of the first epoxy resin is excessively increased, the resolution may be reduced during pattern formation using the photosensitive resin composition, making it difficult to implement fine patterns.

[0084] In addition, the first epoxy resin may have an epoxy equivalent of 190 g / eq to 235 g / eq.

[0085] In addition, the first epoxy resin may have a weight-average molecular weight of 1,500 to 5,000 g / mol. As such, the first epoxy resin has the advantage of having a very small weight-average molecular weight due to steric hindrance caused by an aromatic ring, which results in minimal linewidth expansion (halation).

[0086]

[0087] Additionally, based on 100 wt% of the above-mentioned three or more different types of epoxy resins, the first epoxy resin may be contained in an amount of 55 wt% to 90 wt%, or 65 wt% to 90 wt%, or 70 wt% to 90 wt%, or 75 wt% to 90 wt%, or 85 wt% to 90 wt%. If the content of the first epoxy resin is too low, the peeling time for the cured epoxy resin increases, which may reduce process efficiency. If the content of the first epoxy resin is too high, the sensitivity becomes too fast, which may cause a problem of reduced yield due to decreased uniformity on the same panel (substrate).

[0088] The first epoxy resin may be a bisphenol A novolak-type epoxy resin. The first epoxy resin has excellent chemical resistance, heat resistance, and rigidity due to the aromatic ring, and can increase curing reactivity while maintaining the curing framework. Specific examples of the bisphenol A novolak-type epoxy resin are not significantly limited, but as an example, an epoxy resin having the structure of the following chemical formula A may be cited.

[0089] [Chemical Formula A]

[0090]

[0091] In the above chemical formula A, n is an integer greater than or equal to 1.

[0092]

[0093] More specifically, examples of the above-mentioned bisphenol A novolak type epoxy resin include KEB-3165M80 or KEB-3180M80.

[0094]

[0095] Meanwhile, the second epoxy resin may have a softening point of 65°C to 75°C.

[0096] In addition, the second epoxy resin may have an epoxy equivalent of 160 g / eq to 180 g / eq.

[0097] In addition, based on 100% by weight of the three or more different types of epoxy resins mentioned above, the second epoxy resin may be contained in an amount of 0.1% to 5% by weight, or 1% to 5% by weight, or 1% to 3% by weight, or 1% to 2% by weight. If the content of the second epoxy resin is too low, the peeling time for the cured epoxy resin may increase, thereby reducing process efficiency. If the content of the second epoxy resin is too high, the realization of a fine circuit pattern may be degraded due to line width expansion caused by overpolymerization of the photosensitive resin composition.

[0098] The second epoxy resin above may be a polyfunctional novolak epoxy resin.

[0099] The above photosensitive resin composition includes the polyfunctional novolak epoxy as the second epoxy resin, thereby improving rigidity, chemical resistance, and coefficient of thermal expansion to maintain a high aspect ratio, which makes it easier to form fine patterns than conventional ones.

[0100] The above-mentioned polyfunctional novolak epoxy resin may have three or more functional groups and a weight-average molecular weight of 800 to 1,500 g / mol. The above-mentioned polyfunctional novolak epoxy resin may have three or more, four or more, or five or more functional groups. Accordingly, the coating properties of the dry film photoresist, the mechanical strength of the resist itself after circuit formation, chemical resistance, and coefficient of thermal expansion may be improved.

[0101] Specific examples of the above-mentioned polyfunctional novolak epoxy resin are not limited, but as an example, KES-7270 having the structure of the following chemical formula B can be cited.

[0102] [Chemical Formula B]

[0103]

[0104] In the above chemical formula B, R is hydrogen or methyl, and n is an integer greater than or equal to 1.

[0105] The above photosensitive resin composition includes the above-described polyfunctional epoxy resin, thereby improving rigidity, chemical resistance, and coefficient of thermal expansion to maintain a high aspect ratio, which makes it easier to form fine patterns than conventional ones.

[0106]

[0107] The photosensitive resin composition of the above embodiment may contain 10 parts by weight or more and 150 parts by weight or less of a plasticizer with respect to 100 parts by weight of the second epoxy resin.

[0108] Specifically, the photosensitive resin composition of the above embodiment may include the sensitizer in an amount of 10 parts by weight or more, 15 parts by weight or more, 25 parts by weight or more, 150 parts by weight or less, 125 parts by weight or less, or 120 parts by weight or less, based on 100 parts by weight of the second epoxy resin, or 10 parts by weight or more and 150 parts by weight or less, 10 parts by weight or more and 125 parts by weight or less, 10 parts by weight or more and 120 parts by weight or less, 15 parts by weight or more and 150 parts by weight or less, 15 parts by weight or more and 125 parts by weight or less, 15 parts by weight or more and 120 parts by weight or less, 25 parts by weight or more and 150 parts by weight or less, 25 parts by weight or more and 125 parts by weight or less, or 25 parts by weight or more and 120 parts by weight or less.

[0109]

[0110] If the photosensitive resin composition of the above embodiment contains less than 10 parts by weight of the sensitizer per 100 parts by weight of the second epoxy resin, technical problems such as pattern loss and pattern warping may occur due to a decrease in curing degree caused by a decrease in absorption intensity in the long wavelength band, and if it contains more than 150 parts by weight, technical problems such as a decrease in resolution due to an increase in curing density and the occurrence of non-perfection due to line width expansion may occur.

[0111]

[0112] Meanwhile, the third epoxy resin may have a softening point of 60°C to 102°C, or 60°C to 70°C, or 91°C to 102°C. On the other hand, if the softening point of the third epoxy resin is reduced to less than 60°C, a problem may occur in which the photosensitive resin layer comes into contact with the exposure equipment during the exposure process, which is essential for pattern formation using the photosensitive resin composition, and the sticky, uncured photosensitive resin layer adheres to the exposure equipment, contaminating the exposure equipment. In addition, if the softening point of the third epoxy resin is increased to more than 102°C, the resolution may be reduced during pattern formation using the photosensitive resin composition, making it difficult to implement fine patterns.

[0113] In addition, the third epoxy resin may have an epoxy equivalent of 450 g / eq to 1000 g / eq, or 450 g / eq to 500 g / eq, or 900 g / eq to 1000 g / eq.

[0114] In addition, the third epoxy resin may have a weight-average molecular weight of 1,500 to 5,000 g / mol. As such, the third epoxy resin has the advantage of having a very small weight-average molecular weight due to steric hindrance caused by an aromatic ring, which results in minimal linewidth expansion (halation).

[0115] In addition, based on 100% by weight of the above three or more different types of epoxy resins, the third epoxy resin may be contained in an amount of 1% to 20% by weight, or 5% to 20% by weight, or 5% to 15% by weight, or 5% to 10% by weight. If the content of the third epoxy resin is too low, the degree of polymerization becomes insufficient, and circuit loss problems may occur due to reduced solvent resistance and chemical resistance. If the content of the third epoxy resin is too high, the realization of fine circuit patterns may be reduced due to line width expansion caused by overpolymerization of the photosensitive resin composition.

[0116]

[0117] The third epoxy resin may be a bisphenol A type epoxy resin. The second epoxy resin may have excellent chemical resistance, heat resistance, and rigidity due to the aromatic ring, and may have excellent flexibility and adhesion. Specific examples of the bisphenol A type epoxy resin are not significantly limited, but as an example, an epoxy resin having the structure of the following chemical formula C may be cited.

[0118] [Chemical Formula C]

[0119]

[0120] In the above chemical formula C, n is an integer greater than or equal to 1.

[0121] More specifically, examples of the above-mentioned bisphenol A type epoxy resin include KER-3001 (YD-011) or KER-3004 (YD-014).

[0122]

[0123] The photosensitive resin composition of the above embodiment may further include a UV absorber; an additive; and a solvent.

[0124] The above UV absorber uses a hydroxyphenylbenzotriazole-based liquid UV absorber with excellent coating properties that has thermal stability and durability of the photocuring film formed by an epoxy resin and a cationic initiator.

[0125] The above UV absorber may be, for example, one or more selected from the group consisting of TINUVIN (registered trademark) 384-2, 292, 477, 770, and 479.

[0126]

[0127] The above UV absorber comprises 0.01 to 2.0 parts by weight per 100 parts by weight of the epoxy resin.

[0128]

[0129] The amount of the solvent added is not particularly limited, but for example, it may be included in an amount of 1.0 to 10.0 parts by weight per 100 parts by weight of the epoxy resin.

[0130] The above solvent is not limited in type as long as it can dissolve each component and is chemically stable, and examples include alcohol, ether, glycol ether, ethylene glycol alkyl ether acetate, diethylene glycol, propylene glycol monoalkyl ether, propylene glycol alkyl ether acetate, propylene glycol alkyl ether propionate, aromatic hydrocarbons, ketones, esters, etc.

[0131] Specifically, the solvent may be one or more selected from the group consisting of butanol, dimethylformamide, N-methyl-2-pyrrolidone, gamma-butyrolactone, butylcapitol, butylcellosolve, methylcellosolve, butyl acetate, diethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether propionate, dipropylene glycol dimethyl ether, cyclohexanone, methyl ethyl ketone (MEK), and propylene glycol monomethyl ether acetate (PGMEA).

[0132] In addition, additives may be included to the extent that they do not impair the purpose of the present invention.

[0133] For example, the above additive may include various additives such as leveling agents, curing accelerators, antioxidants, fillers, reaction retardants, anti-aging agents, pigments (dyes), plasticizers, flame retardants, surfactants, dispersants, dehydrating agents, adhesion promoters, and antistatic agents.

[0134] Specifically, the above additive may include a leveling agent, and the leveling agent may be a polyether modified polysiloxane.

[0135] In addition, the content of the above additive is not particularly limited, but for example, it may be included in an amount of 0.01 to 3.0 parts by weight per 100 parts by weight of the epoxy resin.

[0136]

[0137] For a photosensitive resin layer containing the photosensitive resin composition of the above embodiment, the minimum radius at which no breakage occurs during 20 repeated bending tests using a Mandrel device may be 20 mm or less.

[0138] Specifically, regarding the photosensitive resin layer, five specimens per sample are bent 20 times repeatedly at a radius of curvature of 35mm / 30mm / 25mm / 20mm / 15mm / 10mm / 8mm using a Mandrel device, and then the occurrence of cracks or damage is visually checked, and the minimum radius where damage does not occur may be 20mm or less.

[0139] Specifically, for a photosensitive resin layer containing the photosensitive resin composition of the above embodiment, the minimum radius at which breakage occurs during a 20-cycle repeated bending test using a Mandrel device may be 20 mm or less, or 5 mm or more and 20 mm or less.

[0140] As the photosensitive resin composition described above includes a plasticizer comprising an alkyl group represented by Chemical Formula 1, the rigidity within the film is lowered and flexibility is increased, so that the photosensitive resin layer containing the photosensitive resin composition of the above embodiment can achieve excellent flexibility.

[0141] According to another embodiment of the invention, a dry film photoresist comprising a photosensitive resin layer containing the photosensitive resin composition of the first embodiment may be provided. The details regarding the photosensitive resin composition include all the details described above in the first embodiment.

[0142] Specifically, the photosensitive resin layer may include a dried or cured product of the photosensitive resin composition of the above embodiment. The dried product refers to a material obtained through a drying process of the photosensitive resin composition of the above embodiment. The cured product refers to a material obtained through a curing process of the photosensitive resin composition of the above embodiment. Although the thickness of the photosensitive resin layer is not significantly limited, it can be freely adjusted, for example, within a range of 0.01 μm to 1 mm.

[0143] The thickness of the dry film photoresist is not significantly limited, but can be freely adjusted within, for example, a range of 0.01 μm to 1 mm. When the thickness of the dry film photoresist increases or decreases by a specific amount, the physical properties measured in the dry film photoresist can also change by a certain amount.

[0144] The above dry film photoresist may further include a substrate film and a protective film. The substrate film serves as a support for the photosensitive resin layer during the manufacture of the dry film photoresist, thereby facilitating easy handling during the exposure of the photosensitive resin layer having adhesive properties.

[0145] The above-mentioned substrate film may be any type of plastic film, and may include one or more plastic films selected from the group consisting of, for example, acrylic film, polyethylene terephthalate (PET) film, triacetylcellulose (TAC) film, polynorbornene (PNB) film, cycloolefin polymer (COP) film, and polycarbonate (PC) film. The thickness of the above-mentioned substrate film is not significantly limited, but can be freely adjusted within, for example, a range of 0.01 μm to 1 mm.

[0146] The above protective film serves as a protective cover that prevents damage to the resist during handling and protects the photosensitive resin layer from foreign substances such as dust, and is laminated on the back side where the substrate film of the photosensitive resin layer is not formed. As the protective film serves to protect the photosensitive resin layer from the outside, it requires appropriate release properties and adhesiveness so that it can be easily detached when applying the dry film photoresist to subsequent processes, while preventing release during storage and distribution.

[0147] The above protective film may be any type of plastic film, and may include one or more plastic films selected from the group consisting of, for example, acrylic film, polyethylene (PE) film, polyethylene terephthalate (PET) film, triacetylcellulose (TAC) film, polynorbornene (PNB) film, cycloolefin polymer (COP) film, and polycarbonate (PC) film. The thickness of the above protective film is not significantly limited, but can be freely adjusted within, for example, a range of 0.01 μm to 1 mm.

[0148]

[0149] For the above dry film photoresist, the minimum radius at which no breakage occurs during 20 repeated bending tests using a Mandrel device may be 20 mm or less.

[0150] Specifically, regarding the dry film photoresist, five specimens per sample are bent 20 times repeatedly at a radius of curvature of 35mm / 30mm / 25mm / 20mm / 15mm / 10mm / 8mm using a Mandrel device, and then the occurrence of cracks or breakage is visually checked, and the minimum radius where no breakage occurs may be 20mm or less.

[0151] Specifically, for the dry film photoresist, the minimum radius at which breakage occurs during a 20-cycle repeated bending test using a Mandrel device may be 20 mm or less, or 5 mm or more and 20 mm or less.

[0152] As the above photosensitive resin composition includes a plasticizer comprising an alkyl group represented by Chemical Formula 1 as described above, the rigidity within the film is lowered and flexibility is increased, so that the dry film photoresist of the above embodiment can achieve excellent flexibility.

[0153]

[0154] Examples of methods for manufacturing the above dry film photoresist are not significantly limited. For example, a photosensitive resin composition of the above embodiment can be coated onto a conventional substrate film, such as polyethylene terephthalate, using a conventional coating method, dried, and then a dry film can be manufactured by laminating a conventional protective film, such as polyethylene, onto the surface of the dried photosensitive resin layer.

[0155] The method of coating the photosensitive resin composition of the above embodiment is not particularly limited, and, for example, a method such as a coating bar may be used.

[0156] The step of drying the above-mentioned coated photosensitive resin composition can be carried out by a heating means such as a hot air oven, a hot plate, a hot air circulation furnace, or an infrared furnace, and can be performed at a temperature of 50°C or higher and 120°C or lower.

[0157]

[0158] In addition, according to another embodiment of the present invention, a method for manufacturing a dry film photoresist may be provided, comprising the step of coating the photosensitive resin composition on a polymer substrate.

[0159] The above polymer substrate refers to the substrate film described above. Accordingly, the content regarding the above polymer substrate includes all the details described above in the above embodiment.

[0160] The method of coating the above photosensitive resin composition onto a polymer substrate can be carried out according to methods well known in the art. For example, comma coating, slot die, lip die, spin coating, etc. may be used, but are not limited thereto.

[0161] In addition, after the step of coating the photosensitive resin composition on a polymer substrate, the method may further include a step of drying the coated photosensitive resin composition.

[0162] The step of drying the above-mentioned coated photosensitive resin composition can be carried out by a heating means such as a hot air oven, a hot plate, a hot air circulation furnace, or an infrared furnace, and can be performed at a temperature of 50°C or higher and 140°C or 80°C to 135°C or 85°C to 130°C.

[0163] However, the above drying is preferably performed for 25 to 50 minutes or 30 to 40 minutes within the above temperature range. That is, the photosensitive resin layer is a dried or cured product dried for 25 to 50 minutes at a temperature of 50°C or higher and 140°C or lower, and this may be a single layer of photosensitive resin. Through this, the thickness of the photosensitive resin layer is 85 μm or more or 100 μm or more, and the resolution of the resist pattern based on a 120 μm film of the photosensitive resin layer after exposure and development may be 20 μm or less. Accordingly, according to the present invention, it is possible to implement a fine pattern of 20 μm or less on a dry film resist.

[0164] In addition, if the above drying is carried out at a temperature exceeding 140°C for less than 25 minutes, the solvent and bubbles may remain within the dried resin monolayer due to the increased solvent evaporation rate, which may cause the resolution pitch of the photosensitive resin monolayer to increase after exposure and development, making it difficult to implement a fine circuit pattern. Furthermore, if the above drying is carried out at a temperature below 50°C for more than 50 minutes, the drying time may increase excessively, leading to a decrease in process efficiency.

[0165]

[0166] According to another embodiment of the invention, a resist pattern may be provided comprising a pattern of a photosensitive resin layer containing the photosensitive resin composition of the first embodiment. The details regarding the photosensitive resin composition include all the details described above in the first embodiment.

[0167] The pattern of the above photosensitive resin layer may be a photosensitive composition in the form of a pattern having an opening.

[0168] The above resist pattern can maintain an aspect ratio of 1:20 or higher, or 1:21 or higher, or 1:22 or higher, or 1:24 or higher.

[0169] Examples of methods for forming the above-described photosensitive resin pattern include coating a photosensitive resin composition of the dry film photoresist of the other embodiment onto a substrate, stacking a photosensitive resin layer on the substrate by drying in the manner described above, and then proceeding with exposure, baking, and development. Additionally, methods include stacking a photosensitive resin layer of the photosensitive element of the other embodiment onto a substrate, and then proceeding with exposure and development.

[0170] The thickness of the photosensitive resin single layer may be 100 μm or more, or 120 μm or more, or 1000 μm or less, or 85 μm to 1000 μm, or 100 μm to 1000 μm, or 120 μm to 1000 μm. Through the method described above, a fine pitch of the photosensitive resin single layer can be formed after exposure, baking after exposure, and development, thereby enabling the manufacture of a high-resolution microcircuit pattern.

[0171] As a substrate, the following may be used: a copper foil laminate, a glass substrate on which a transparent electrode such as ITO and IZO is sputtered or deposited, a film substrate such as the same, a glass substrate coated with dielectric paste, a silicon wafer, a glass wafer on which amorphous silicon is deposited, a silicon wafer on which a metal thin film such as copper, tantalum, or molybdenum is sputtered.

[0172] The above exposure process can be carried out using light sources well known in this field, such as UV, visible light, and lasers. Among these, it is preferable to use a laser direct exposure machine that includes light with a wavelength of 350 to 410 nm, particularly an i-line (365 nm) light source. When using a laser direct exposure machine, the process can be performed under conditions where the exposure energy is 300 to 700 mJ / ㎠ or less, whereas when using a general lamp exposure machine, the process can be performed under conditions where the exposure energy is 200 mJ / ㎠ or less, making it useful for manufacturing images of PCBs, lead frames, PDPs, and other display devices.

[0173] In addition, to increase the efficiency of the above-mentioned cation initiator, a post-exposure baking process may be performed. For the post-exposure baking process, a hot air oven or a hot plate may be used. As a preferred example, when using a hot air oven, the baking process may be performed at 70 to 90°C for 10 to 60 minutes.

[0174] The development process can be carried out by the dipping method, shower method, spray method, brush method, etc., and as the developer, an organic developer containing an organic solvent such as PGMEA is used instead of an alkaline developer, unlike the developer of a general photoresist. As such an organic developer, organic solvents such as methyl-2-hydroxyisobutyrate, ethylene glycol methyl ether acetate, 2-methoxy-1-methyl ethyl ester, propylene acetate, dibutyl ether, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate (PGMEA), and propylene glycol dimethyl ether can be used, and these can be used alone or in a mixture of two or more. According to a preferred embodiment, the developer may be PGMEA.

[0175] Accordingly, the photosensitive resin layer may be developed with one or more organic solvents selected from the group consisting of methyl-2-hydroxyisobutyrate, ethylene glycol methyl ether acetate, 2-methoxy-1-methyl ethyl ester, propylene acetate, dibutyl ether, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, and propylene glycol dimethyl ether.

[0176] In the case where the dry film photoresist or photosensitive element of the above other embodiment has a protective film on the photosensitive resin layer, the photosensitive resin layer may undergo an additional process of removing the protective film before the lamination process on the circuit board or substrate for manufacturing a display device.

[0177] In addition, if the dry film photoresist or photosensitive element of the above other embodiment has a polymer substrate or substrate film laminated on one surface of a photosensitive resin layer, a process of removing the polymer substrate or substrate film immediately after the exposure process may be further performed.

[0178]

[0179] According to another embodiment of the invention, a display device may be provided comprising the resist pattern or a metal pattern formed by the resist pattern. Additionally, the resist pattern or the metal pattern formed by the resist pattern may be included in a circuit board.

[0180] That is, a circuit board or display device may be provided comprising a resist pattern of the other embodiment, or a metal pattern formed by the resist pattern of the other embodiment. The details regarding the resist pattern include all details described above in the other embodiment.

[0181]

[0182] The specific details regarding the above circuit board or display device are not particularly limited, and various conventionally known technical configurations can be applied without restriction.

[0183] The metal pattern described above can be formed by the resist pattern described above. Specifically, the metal pattern can be formed by performing etching or plating through the openings included in the resist pattern. That is, the metal pattern may include the lower metal remaining after etching the lower metal of the resist pattern through the openings included in the resist pattern, or the metal plated in the openings included in the resist pattern.

[0184] Specifically, for example, by etching or plating the lower substrate exposed by the above-described resist pattern, a barrier of a power inductor, a microelectromechanical system (MEMS) component, an electronic circuit, a conductor pattern, a printed circuit board, a lead frame, an ITO electrode, a black matrix, a semiconductor bump, etc., can be manufactured. If necessary, after the etching or plating, the resist pattern may be peeled off and removed from the substrate using an aqueous solution having a stronger alkalinity than the developer.

[0185] As described above, the resist pattern can achieve a fine pitch with a resolution of 20 μm or less based on a 120 μm film.

[0186] The above-mentioned resist pattern can be applied to the barrier of a power inductor or to a microelectromechanical system (MEMS) component, and best applied to the barrier of a power inductor.

[0187] Accordingly, by using the dry film photoresist of the present invention, a circuit having a fine line width is formed through a conventional etching / plating process, and productivity can be maximized in generating images for power inductors, MEMS, PCB lead frames, PDPs, other display devices, semiconductor devices, etc., having a fine line width through a known process.

[0188]

[0189] By using the photosensitive resin composition of the present invention, the resolution of the resist pattern based on a 120 μm film can be 20 μm or less. In particular, by implementing the resist pattern with a fine pitch such that the resolution based on a 120 μm film is 20 μm or less, power inductor efficiency and MEMS precision can be maximized.

[0190] In addition, the photosensitive resin composition of the present invention is a material that can be applied in various ways to wearable electronic devices that are becoming increasingly miniaturized as high-resolution film materials.

[0191]

[0192] The operation and effects of the invention will be described in more detail below through specific embodiments. However, these embodiments are merely examples of the invention and do not define the scope of the invention.

[0193]

[0194] <Examples and Comparative Examples: Preparation of Photosensitive Resin Composition and Dry Film Photoresist>

[0195] A photosensitive resin composition was prepared by mixing each component according to the composition and content of Table 1 below (Unit: g)

[0196]

[0197] (Ingredients)

[0198] (A) Epoxy resin

[0199] A-1: Bisphenol A Novolak Epoxy (KEB-3165M80, Kolon Industries)

[0200] A-2: Polyfunctional Epoxy (Novolac Epoxy, KES-7270M70, Kolon Industries)

[0201] A-3: Bisphenol A Epoxy (KER-3004, Manufacturer: Kumho P&B Chemical)

[0202] (B) Cation initiator:

[0203] B: TR-PAG-21608, Thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium) bis tetrakis(pentafluorophenyl) borate

[0204] (C) Plasticizer

[0205] C-1: TEG-EH, Triethylene glycol bis(2-ethylhexanoate)

[0206] C-2: Texanol, 2,2,4-trimethyl-1,3-pentanediol isobutyrate

[0207] C-3: TXIB, 2,2,4-Trimethyl-1,3-pentanediol diisobutyrate

[0208] C-4: Benzoflex 9-88, Dipropylene glycol dibenzoate

[0209] (D) UV absorber

[0210] D: Tinuvin 384-2, Benzenepropanoic acid, 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy-, C7-9-branched and linear alkyl esters

[0211] (E) Leveling agent: Tego Flow 425 (Polyether modified polysiloxane)

[0212] (F) Solvent: MEK (Methyl Ethyl ketone)

[0213]

[0214] The above-mentioned photosensitive resin composition was coated onto a PET film with a thickness of 36 μm using a film applicator to form a photosensitive resin layer, and then dried at 100°C for 60 minutes using a hot air oven to form a photosensitive resin layer with a thickness of 120 μm.

[0215] A dry film photoresist was prepared by laminating a protective film (polyethylene) onto a photosensitive resin layer after drying was complete.

[0216]

[0217] <Experimental Example>

[0218] For the dry film photoresists prepared in the above examples and comparative examples, physical properties were measured by the following method, and the results are shown in Table 1.

[0219]

[0220] 1. Resolution (Line / Space, Unit: μm)

[0221] To remove the protective film of the dry film photoresist prepared in the above examples and comparative examples so that the photosensitive resin layer of the dry film photoresist comes into contact with the surface of the copper layer of a 1.6 mm thick brush-polished copper laminate, the substrate preheating roll temperature is 120 ℃, the laminator roll temperature is 115 ℃, and the roll pressure is 4.0 kgf / ㎠. Then, a laminate was formed by lamination using a HAKUTO MACH 610i under a roll speed of 0.5 min / m.

[0222] After peeling off the PET film supporting the dry film photoresist from the above laminate, ultraviolet light with a wavelength of 355 nm was irradiated onto the organic coating using Orbotech’s Paragon-8000m and a Stouffer Graphic Arts Equipment’s 41-step tablet with an exposure amount that resulted in 17 remaining steps, then left for 15 minutes, and cured at 85°C for 20 minutes using a hot air oven. Afterward, development was performed using a dipping method with a 98% PGMEA solution for 20 minutes, and the resolution was measured.

[0223] In the developed laminate, the resolution was evaluated by measuring the minimum value of the spacing between photosensitive resin layers using a ZEISS AXIOPHOT Microscope. The smaller this value, the better the resolution value can be evaluated.

[0224]

[0225] 2. Evaluation of Copper Plating Resistance

[0226] After the development is complete, a 2.5-inch acrylic tape is attached to a specimen with a measured copper plating pattern after 90㎛ copper plating is performed on the laminate. After separating the acrylic tape from the specimen at a 90-degree angle using a SurTA (ChemiLAB) device, the presence or absence of lifting of the copper plating pattern is checked. Copper plating resistance was measured using this tape test method.

[0227] (Evaluation Criteria)

[0228] ○: No lifting or peeling of the pattern plating

[0229] X: Pattern plating peeling and peeling occurred

[0230]

[0231] 3. Flexibility Assessment

[0232] To remove the protective film of the dry film photoresist prepared in the above examples and comparative examples so that the photosensitive resin layer of the dry film photoresist comes into contact with the surface of the copper layer of a 1.6 mm thick brush-polished copper laminate, the substrate preheating roll temperature is 120 ℃, the laminator roll temperature is 115 ℃, and the roll pressure is 4.0 kgf / ㎠. Then, a laminate was formed by lamination using a HAKUTO MACH 610i under a roll speed of 0.5 min / m.

[0233] The above laminate was cut into 25mm x 150mm (width x height) to produce specimens, and the produced specimens were bent 20 times using a Mandrel device at curvature radii of 35mm / 30mm / 25mm / 20mm / 15mm / 10mm / 8mm, with 5 specimens per sample, and then the occurrence of cracks or breakage was visually checked and the minimum radius at which no breakage occurred was measured.

[0234]

[0235] Example Comparative Example 1 231 234 567 Epoxy Resin (A) A-1: ​​KEB-3165M80 85.085.085.085.085.085.085.085.085.085.085.0A-2: KES-7270M70 1.81.81.81.81.81.81.81.81.81.81.8A-3: KER-300 49.09.09.09.09.09.09.09.09.09.09.0 Cationic Initiator (B) B: TR-PAG-2160 80.60.60.60.60.60.60.60.60.60.60.6 Plasticizer (C) C-1: TEG-EH 0.5 1.02.0 C-2: Texanol 0.52.0 C-3:TXIB 0.52.0 C-4:Benzoflex 9-88 0.52.0 UV Absorber D:Tinuvin384-20.10.10.10.10.10.10.10.10.10.10.10.1 Leveling Agent E:Polysiloxane 0.10.10.10.10.10.10.10.10.10.10.1 Solvent F:MEK2.9 2.4 1.4 3.4 2.9 1.4 2.9 1.4 2.9 1.4 2.9 1.4 Film Manufacturing Thickness (㎛) 120 120 120 120 120 120 120 120 120 Exposure Amount (mJ / cm²) 2 )400400400400400400400400400400400 Resolution (L / S) (㎛)6 / 146 / 146 / 146 / 146 / 146 / 158 / 158 / 156 / 148 / 15 Copper Plating Resistance Evaluation (Plating Thickness 80㎛)OOOOOOOOOO Film Flexibility Before Curing (Mandrel, R-value)2015835353035303025

[0236] Raw Material Type Raw Material Name Softening Point (°C) Epoxy Equivalent (g / eq) Bisphenol A Novolak Type Epoxy KEB-31 65M 80 60 ~ 70 190~235 Polyfunctional Novolak Epoxy KES-72 70 65~75 160~180 Bisphenol A Type Epoxy KER-3004(YD-014) 91 ~ 102 900~1,000

[0237] * Measurement of Softening Point: The softening point was measured according to the ASTM E 28-14 standard. Specifically, melted epoxy resin was poured into a round ring; once the resin solidified, the ring was mounted on a softening point measuring device, and a steel ball was placed on top of the solidified resin. The temperature was then increased at a rate of 5 ℃ / min, and the softening point was determined as the temperature at which the steel ball fell off as the resin melted. * Measurement of Epoxy Equivalent: An appropriate amount of the sample (estimated equivalent value / 400) was placed in an Erlenmeyer flask and completely dissolved by adding 15 ml of 1,4-dioxane. After dissolution, 25 ml of 0.2N HCl (dioxane) was accurately added. The lid was closed, and one or two drops of dioxane were placed at the boundary with the flask. The mixture was then allowed to react at room temperature for 30 minutes. After the reaction, the flask and stopper were rinsed with approximately 10 ml of 2-methoxyethanol and placed back into the flask. Three drops of cresol red indicator were added, and titration was performed with 0.1 NaOH (methanol) solution, with the endpoint being the point where the color changed from pink to yellow and turned purple.

[0238] In addition, a blank test was conducted using the same method, except that no sample was added.

[0239] And, the epoxy equivalent was calculated using the following mathematical formula 1.

[0240] [Mathematical Formula 1]

[0241] Epoxy equivalent (g / eq) = 10,000 x W / {(BA) x F}

[0242] B: 0.1 N NaOH (methanol) consumption (ml) during blank titration

[0243] A: 0.1 N NaOH (methanol) consumption (ml) during sample titration

[0244] F: 0.1 N NaOH (methanol) Factor

[0245] W: Sample amount (g)

[0246]

[0247] Through the results of Table 1, it was confirmed that Examples 1 to 3, by including a plasticizer of a specific structure, can be designed to enable the formation of fine patterns by exhibiting excellent resolution and copper plating resistance, as well as being easy to peel off and having excellent flexibility.

[0248] On the other hand, Comparative Examples 1 to 7 did not use a plasticizer or used a general plasticizer different from the examples, so it was confirmed that the flexibility was poor.

Claims

1. Epoxy resin; a cationic initiator containing a sulfonium complex salt; and a plasticizer; comprising, A photosensitive resin composition comprising an alkyl group represented by the following chemical formula 1, wherein the above plasticizer: [Chemical Formula 1] In the above chemical formula 1, R1 is hydrogen or an alkyl group having 2 or more carbon atoms, and R2 is hydrogen or an alkyl group with 1 or more carbon atoms.

2. In Paragraph 1, With respect to the photosensitive resin layer containing the above photosensitive resin composition, A photosensitive resin composition having a minimum radius of 20 mm or less that does not break during 20 repeated bending tests using a mandrel device.

3. In Paragraph 1, A photosensitive resin composition comprising one or more plasticizers selected from the group consisting of triethylene glycol bis(2-ethylhexanoate), di-2-ethylhexyl terephthalate, di-isononyl cyclohexane-1,2-dicarboxylate, and di-isononyl adipate.

4. In Paragraph 1, A photosensitive resin composition comprising one or more selected from the group consisting of thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium)bistetrakis(pentafluorophenyl)borate, thio-p-phenylenebis(4,4'-dimethyldiphenylsulfonium)hexafluorophosphate, triarylsulfonium bistetrakis(pentafluorophenyl)borate, triarylsulfonium hexafluorophosphate, and 4-{[4-(diphenylsulfonium)phenyl]sulfanyl}phenyl)diphenylsulfonium)hexafluorophosphate.

5. In Paragraph 1, A photosensitive resin composition comprising the above plasticizer in an amount of 0.1 parts by weight or more and 5.0 parts by weight or less per 100 parts by weight of the epoxy resin.

6. In Paragraph 1, A photosensitive resin composition comprising the above plasticizer in an amount of 50 parts by weight or more and 400 parts by weight or less per 100 parts by weight of the above cation initiator.

7. In Paragraph 1, A photosensitive resin composition comprising the above-mentioned cationic initiator in an amount of 0.1 parts by weight or more and 5.0 parts by weight or less per 100 parts by weight of the above-mentioned epoxy resin.

8. In Paragraph 1, The above epoxy resin is a photosensitive resin composition comprising three or more different types of epoxy resins, including a first epoxy resin, a second epoxy resin, and a third epoxy resin.

9. In Paragraph 8, The above three or more different types of epoxy resins are, 55% to 90% by weight of first epoxy resin; 0.1% to 5% by weight of a second epoxy resin; and A photosensitive resin composition comprising 1% to 20% by weight of a third epoxy resin.

10. In Paragraph 8, The first epoxy resin above is a bisphenol A novolak-type epoxy resin, and The above second epoxy resin is a polyfunctional novolak epoxy resin, and The above-mentioned third epoxy resin is a bisphenol A type epoxy resin, a photosensitive resin composition.

11. In Paragraph 8, The above-mentioned first epoxy resin is a photosensitive resin composition having a softening point of 60°C to 85°C.

12. In Paragraph 8, The above second epoxy resin is a photosensitive resin composition having a softening point of 65°C to 75°C.

13. In Paragraph 8, The above third epoxy resin is a photosensitive resin composition having a softening point of 60°C to 102°C.

14. In Paragraph 8, The above second epoxy resin is a photosensitive resin composition having an epoxy equivalent weight of 160 g / eq to 180 g / eq.

15. In Paragraph 8, The above photosensitive resin composition comprises a plasticizer in an amount of 10 parts by weight or more and 150 parts by weight or less per 100 parts by weight of the second epoxy resin.

16. In Paragraph 1, The above photosensitive resin composition further comprises a UV absorber; an additive; and a solvent.

17. A dry film photoresist comprising a photosensitive resin layer containing the photosensitive resin composition of claim 1.

18. In Paragraph 17, The above dry film photoresist is a dry film photoresist having a minimum radius of 20 mm or less that does not break when subjected to 20 repeated bending tests using a Mandrel device.

19. A method for manufacturing a dry film photoresist comprising the step of coating a photosensitive resin composition of claim 1 onto a polymer substrate.

20. A resist pattern comprising a pattern of a photosensitive resin layer containing the photosensitive resin composition of claim 1.

21. A display device comprising the resist pattern of claim 20, or a metal pattern formed by the resist pattern of claim 20.

Images