PHOTOSENSITIVE RESIN COMPOSITION AND USE THEREOF

Abstract

The present disclosure discloses a photosensitive resin composition and a use the same. The resin composition of the present disclosure includes 40-70 parts by weight of an alkali-soluble resin, 20-50 parts by weight of a photopolymerizable monomer, 0.5-10.0 parts by weight of a photoinitiator, and 0.1-10.0 parts by weight of additives. The photopolymerizable monomer includes 0.5-15.0 parts by weight of a monomer containing carbonate structure. The photosensitive resin composition is used as a dry film resist. It has characteristics such as easy breakage of film strip, smaller film strip fragments, faster film strip speed, excellent flexibility, and good circuit resolution and adhesion, thereby effectively improving production efficiency and product yield.

Claims

1. A photosensitive resin composition, wherein comprising 40-70 parts by weight of an alkali-soluble resin, 20-50 parts by weight of a photopolymerizable monomer, 0.5-10.0 parts by weight of a photoinitiator, and 0.1-10.0 parts by weight of additives; in the photosensitive resin composition, the photopolymerizable monomer comprising 0.5-15.0 parts by weight of a monomer containing a carbonate structure, and/or the additives comprising 0.1-8.0 parts by weight of a plasticizer containing a carbonate structure.

2. The photosensitive resin composition according to claim 1, wherein the monomer containing a carbonate structure is one or more of the following three general structures: ##STR00003## wherein, in the above general formulas (1), (2) and (3), R1 is hydrogen or phenyl; R2 is hydrogen or methyl; R3 is 1,4-phenylene, or an alkylene group with 1˜10 carbon atoms; R4 is a straight or branched chain alkyl group with 1˜10 carbon atoms, or an alkenyl group with 2˜10 carbon atoms; R5 is selected from a group consisting of a linear or branched alkylene group with 1˜10 carbon atoms, an arylene group with 6˜10 carbon atoms, or a linear or branched alkylene group with 1˜10 carbon atoms in which acyclic —CH2— is optionally substituted by —O—, —S— or 1,4-phenylene, and an arylene group with 6-10 carbon atoms in which acyclic —CH2— is optionally substituted by —O—, —S— or 1,4-phenylene.

3. The photosensitive resin composition according to claim 1, wherein the monomer containing carbonate structure is selected one or more from cinnamyl methyl carbonate, tert-butyl allyl formate, tert-Butyl 4-vinyl phenyl carbonate, allyl methyl carbonate, bis(2-methylallyl) carbonate, and allyl diethylene glycol dicarbonate.

4. The photosensitive resin composition according to claim 1, wherein the plasticizer containing a carbonate structure has a structural formula as shown in general formula (4): ##STR00004## wherein, R1 and R2 are independently selected from C1-C10 linear or branched chain alkyl, C3-C10 cycloalkyl, C4-C10 alkylcycloalkyl or cycloalkylalkyl, phenyl, benzyl, C6-C10 aryl groups, C4-C10 heteroaryl groups, C2-C10 heterocyclic groups, or C2-C20 ester-containing groups; and the acyclic —CH2— in the above groups is capable to be optionally substituted by —O—, —CO—, —NH—, —S— or 1,4-phenylene.

5. The photosensitive resin composition according to claim 1, wherein the photopolymerizable monomer contains an ethylenically unsaturated double bond monomer.

6. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin is formed by copolymerization of at least two of methacrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, benzyl (meth)acrylate, styrene, and styrene derivatives.

7. The photosensitive resin composition according to claim 1, wherein the alkali-soluble resin has a weight average molecular weight of 20,000 to 150,000, and an acid value of 100 to 350 mg KOH/g.

8. The photosensitive resin composition according to claim 1, wherein the photoinitiator is one or more selected from a group consisting of benzoin ether, benzophenone and derivatives thereof, thioxanthone-based compounds, anthraquinone and derivatives thereof, thioxanthone series compounds, and hexaarylbisimidazole series compounds.

9. The photosensitive resin composition according to claim 1, wherein the additives comprise one or more selected from a group consisting of a plasticizer, a defoamer, and a polymerization inhibitor.

10. Use of the photosensitive resin composition according to claim 1 as a dry film resist.

Description

DESCRIPTION OF EMBODIMENTS

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be described clearly and completely below. Obviously, the described embodiments are a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without inventive work shall fall within the protection scope of the present disclosure.

[0034] Unless otherwise defined, the technical or scientific terms used in the present disclosure shall have the usual meanings understood by those with ordinary skills in the field to which the present disclosure belongs.

[0035] 1. Specific components and the weight ratios thereof in the photosensitive resin compositions of Examples (Ex.) 1-18 and Comparative Examples (Cp. Ex.) 1-4 (see Table 1 and Table 2)

[0036] (1) Alkali-soluble resin A: it is prepared by solution polymerization; the main components may be methacrylic acid/methyl methacrylate/n-butyl methacrylate/lauryl acrylate/styrene=22/40/15/5/18 (Mw=80,000).

[0037] (2) Photopolymerizable monomer B:

[0038] B-1: (8) ethoxylated nonylphenol acrylate, with a molecular weight of 626 (Sartomer);

[0039] B-2: (9) ethoxylated dimethacrylate, with a molecular weight of 598 (Bigen);

[0040] B-3: (3) ethoxylated trimethylolpropane triacrylate, with a molecular weight of 428 (Sartomer);

[0041] B-4: allyl diethylene glycol dicarbonate, (Hubei Guangao Biological Technology Co., Ltd.);

[0042] B-5: allyl methyl carbonate, (Hubei Guangao Biological Technology Co., Ltd.);

[0043] B-6: bis (2-methylallyl) carbonate, (Hubei Guangao Biological Technology Co., Ltd.).

[0044] (3) Photoinitiator C:

[0045] C-1: 2,2′,4-tris(2-chlorophenyl)-5-(3,4-dimethoxyphenyl)-4′,5′-diphenyl-1,1′-diimidazole (Tronly, Changzhou);

[0046] C-2: N-Phenylglycine (Xiya Chemistry).

[0047] (4) Additives D:

[0048] D-1: brilliant green pigment (J&K Scientific, Shanghai);

[0049] D-2: leuco crystal violet (J&K Scientific, Shanghai);

[0050] D-3: tribromomethyl phenyl sulfone (TCI Shanghai);

[0051] D-4: N,N-diethylhydroxylamine (J&K Scientific, Shanghai);

[0052] D-5: dibenzyl carbonate (Hubei Guangao Biological Technology Co., Ltd.);

[0053] D-6: benzyl phenyl carbonate (Hubei Guangao Biological Technology Co., Ltd.);

[0054] D-7: tert-butyl phenyl carbonate (Hubei Guangao Biological Technology Co., Ltd.).

TABLE-US-00001 TABLE 1 The weight ratio of each component of Example (Ex.) 1-9 and Comparative Example (Cp. Ex.) 1-2 Component Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Cp. Cp. (w%) 1 2 3 4 5 6 7 8 9 Ex. Ex. 1 2 Alkali-sol A 50 50 50 50 50 50 60 40 70 60 50 uble resin Photopoly B-1 20 20 20 20 20 25 19 49.5 5 16 5 merizable B-2 10 10 10 10 9 9 10 — — 10 10 monomer B-3 9.5 9.5 9.5 9.5 7.5 8 9 — — 10.5 11.5 B-4 7 — — 3.5 10 5 1.3 0.5 7.5 — 20 B-5 — 7 — 3.5 — — 0.1 — 7.5 — — B-6 — — — — — — — — — — — Photoiniti C-1 2 2 2 2 1.5 1.2 0.5 2.5 2.5 2 2 ator C-2 0.5 0.5 0.5 0.5 1 0.8 - 2.5 2.5 0.5 0.5 Additives D-1 0.05 0.05 0.05 0.05 0.1 0.1 0.05 0.6 0.6 0.05 0.05 D-2 0.4 0.4 0.4 0.4 0.6 0.9 0.05 1.7 1.7 0.4 0.4 D-3 0.5 0.5 0.5 0.5 0.3 — — 2.0 2.0 0.5 0.5 D-4 0.05 0.05 0.05 — — — — 0.7 0.7 0.05 0.05 Total: 100 100 100 100 100 100 100 100 100 100 100

TABLE-US-00002 TABLE 2 The weight ratio of each component of Examples 10-18 and Comparative Example 3-4 Component Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Cp. Cp. (w%) 10 11 12 13 14 15 16 17 18 Ex. 3 Ex. 4 Alkali-sol A 57 57 57 57 54 60 40 70 60 60 60 uble resin Photopoly B-1 17 17 17 17 21 16 50 5 20 16 5 merizable B-2 10 10 10 10 9 9 — 10 — 10 10 monomer B-3 9.5 9.5 9.5 9.5 7.5 7.5 — 5 — 10.5 11.5 Photoiniti C-1 2 2 2 2 2 2 0.5 1 3 2 2 ator C-2 0.5 0.5 0.5 0.5 0.5 0.5 — 1 7 0.5 0.5 Additives D-1 0.05 0.05 0.05 0.05 0.05 0.05 0.5 0.1 0.5 0.05 0.05 D-2 0.4 0.4 0.4 0.4 0.4 0.4 3.2 0.5 1.5 0.4 0.4 D-3 0.5 0.5 0.5 0.5 0.5 0.5 3.0 0.5 3 0.5 0.5 D-4 0.05 0.05 0.05 0.05 0.05 0.05 2.7 0.5 — 0.05 0.05 D-5 3 — — 1.5 5 4 0.1 3 — — 10 D-6 — 3 — 1.5 — — — 3.4 5 — — D-7 — — 3 — — — — — — — — Total: 100 100 100 100 100 100 100 100 100 100 100

[0055] 2. Preparation of photosensitive dry film of Examples and Comparative Examples

[0056] The specific preparation steps may be as follows:

[0057] (1) mixing the components according to the proportions of the components of the photosensitive resin composition in Table 1 and Table 2, then adding acetone; and fully stirring until completely dissolved, such that a resin composition solution with a solid content of 40% can be obtained;

[0058] (2) coating the above resin composition solution evenly on the surface of a PET support film with a thickness of 15 μm by using a coater, and placing the coated PET support film in an oven at 85° C. for 10 minutes to form a dry film resist layer with a thickness of 35 μm, which appears blue-green under a yellow light;

[0059] (3) attaching a polyethylene film protective layer with a thickness of 20 μm to the surface of the dry film resist layer, such that a photosensitive dry film with a three-layer structure can be obtained.

[0060] 3. Sample preparation methods (including filming, exposing, developing, etching, and stripping (removing) film), sample evaluation methods and evaluation results of Examples and Comparative Examples.

[0061] (1) Sample Preparation Method

[0062] Filming:

[0063] polishing the copper clad laminate on its copper surface by a grinder, washing with water, and wiping to obtain a bright and fresh copper surface; setting the pressure roller temperature of the film laminator to 110° C., the conveying speed to 1.5 m/min, and heat bonding under standard pressure.

[0064] Exposing:

[0065] exposing the sample by using Zhisheng Technology M-552 parallel light exposure machine, after standing for more than 15 minutes after filming, performing a photosensitivity test with stouffer 41-step exposure ruler, where the number of exposure grids may be controlled at 16-22 grids, and the exposure energy may be 25-60 mJ/cm.sup.2.

[0066] Developing:

[0067] standing the sample for more than 15 minutes after exposing, and washing the developed sample with water and drying; where the developing temperature may be 30° C., the pressure may be 1.2 Kg/cm.sup.2, the developing solution may be a 1% wt sodium carbonate aqueous solution, and the developing time may be 1.5-2.0 times the minimum developing time.

[0068] Etching:

[0069] etching with acid; where the etching solution may be a copper chloride (CuCl.sub.2)/hydrochloric acid (HCL) system, the etching temperature may be 50° C., the pressure may be 1.2 Kg/cm.sup.2, the specific gravity of the etching solution may be 1.20-1.30 g/mL, the concentration of hydrochloric acid may be 1.5 mol/L, and the concentration of copper ion may be 120-160 g/L.

[0070] Film Stripping:

[0071] removing (stripping) the film and washing with water and drying; where the stripper may be NaOH, the concentration may be 3.0 wt %, the temperature may be 50° C., the pressure may be 1.2 Kg/cm.sup.2, and the stripping time may be 1.5-2.0 times the minimum stripping Time.

[0072] (2) Evaluation Method

[0073] Stripping Speed Evaluation

[0074] The stripping speed may be evaluated by testing the film strip time. The shorter the film strip time, the faster the film strip speed.

[0075] Evaluation of the Size of the Film Strip Fragments

[0076] 1 substrate after filming, exposing, and developing may be taken, cut into a 5*5 cm square, and put into a beaker containing 100 mL film stripper (concentration 3 wt %, temperature 50° C.). It is magnetically stirred for 1 min, and the size of the film strip fragments is observed.

[0077] The evaluation criteria are as follows:

[0078] Good: Fragment size 10-20 mm;

[0079] Normal: Fragment size 20-30 mm;

[0080] Poor: Fragment size above 30 mm or below 5 mm.

[0081] Resolution Evaluation

[0082] Exposing may be carried out using a mask with a wiring pattern with a width of 1:1 for exposed and unexposed parts. After developing at 1.5 times the minimum development time, the minimum mask width that normally forms a cured resist line may be used as the resolution value, and observing may be performed using a magnifying glass.

[0083] Evaluation of Adhesion

[0084] A photosensitive dry film resist may be laminated on a copper board by hot-press filming, and exposing may be carried out using a mask with a wiring pattern with a width of n:400 for exposed and unexposed parts. After developing at 1.5 times the minimum development time, the minimum mask width that normally forms a cured resist line may be used as the adhesion value, and observing may be performed using a magnifying glass.

[0085] Evaluation of Flexibility

[0086] After filming, exposing, and developing, the flexible substrate may be folded 20 times from different angles to observe whether the dry film is cracked, the number of cracks are counted, and a number may be adopted to indicate the result. The smaller the value, the better the flexibility of the dry film.

[0087] The evaluation criteria are as follows:

[0088] Good: Dry film cracked 0 times after folding;

[0089] Normal: Dry film cracked 1-5 times after folding;

[0090] Poor: Dry film cracked more than 5 times after folding.

[0091] (3) See Table 3 and Table 4 for the evaluation results of adhesion, resolution, film strip speed, and film strip fragment size

TABLE-US-00003 TABLE 3 Evaluation results of Examples 1-9 and Comparative Examples 1-2 Perfor Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Ex. 9 Cp. Cp. mance Ex. 1 Ex. 2 Adhesi 27.5 27.5 27.5 27.5 25 27.5 27.5 27.5 27.5 30 27.5 on /μ m Revolut 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 27.5 ion/μ m Film 35 37 36 36 31 37 39 26 46 50 25 strip speed /s Film Good Good Good Good Good Good Good Norm Norm Poor Poo strip /20 /20 /20 /20 /15 /20 /20 a1/5 a1/30 /35 r/5 fragme nt size /mm

[0092] The weight part of the monomer containing carbonate structure in the photopolymerization monomer in Example 1-9 is in the range of 0.1-15.0. From the comparison between Example 1-9 and Comparative Example 1-2 in Table 3, it can be found that: in Examples 1-7, the film stripping breaks cleanly, the film strip speed is fast, the size of the film strip fragments is moderate, and the resolution and adhesion are good. In Examples 8-9, the adhesion and resolution are better, but the film strip fragments are moderate. In Comparative Example 1, the addition amount of the carbonate structure monomer is 0, resulting in unclean rupture of the film strip, film strip speed is reduced, the size of the film strip fragments is larger, and adhesion is decreased. In Comparative Example 2, the weight of the carbonate structure monomer exceeds 15.0, although it has no obvious effect on the resolution and adhesion performance, the size of the film strip fragments is too small, which is not conducive to the recovery of the film strip fragments, and it is easy to block the pipes and nozzles.

TABLE-US-00004 TABLE 4 Evaluation results of Examples 10-18 and Comparative Examples 3-4 Perform Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Cp. Cp. ance 10 11 12 13 14 15 16 17 18 Ex. 3 Ex. 4 Adhesi 30 30 30 30 27.5 30 30 30 30 30 32.5 on / μ m Revolut 32.5 32.5 32.5 32.5 32.5 32.5 32.5 32.5 32.5 32.5 32.5 ion/ μ m Film 40 39 40 41 36 38 38 35 36 54 33 strip speed /s Film Good Good Good Good Good Good Good Good Good Poor Poor strip /20 /20 /20 /20 /15 /15 /20 /15 /15 /35 /<5 fragme nt size /mm Flexibil Good Good Good Good Good Good Good Good Good Poor Good ity grade

[0093] From the comparison of Examples 10-18 and Comparative Examples 3-4, it can be found that the weight of the plasticizer containing carbonate structure in the additives of Example 10-18 is within the range of 0.1-8.0, and the film strip breaks cleanly and the film strip speed is fast; the size of film strip fragments is moderate, and the resolution and adhesion performance are stable, and the flexibility is excellent. In Comparative Example 3, the addition amount of the plasticizer containing carbonate structure is 0, resulting in unclean film strip, the film strip speed is reduced, the size of the film strip fragments is larger, and the flexibility is poor. In Comparative Example 4, the weight of the plasticizer containing carbonate structure exceeds 8.0, although it has no effect on the resolution and adhesion, the size of the film strip fragments is too small, which is not conducive to the recovery and treatment of the film strip fragments, and it is easy to block the pipes and nozzles.

[0094] The photosensitive resin composition of the present disclosure comprises a monomer containing carbonate structure and/or a plasticizer containing carbonate structure, the polymer long chain having a carbonate structure is obtained by photopolymerization. When the resin composition is used as a dry film resist, it has excellent flexibility and can quickly react with the strong alkaline sodium hydroxide or potassium hydroxide film strip solution when removing the film, so as to realize breakage of the long chain of the carbonate structure of the polymer or the carbonate structure of the plasticizer, and decomposition to generate carbon dioxide and small molecules, so that the dry film resist swells and breaks, and quickly peels off from the copper board. Therefore, when the photosensitive resin composition of the present disclosure is used as a dry film resist, it has the characteristics such as easy breakage of film strip, smaller film strip fragments, faster film strip speed, excellent flexibility, and good circuit resolution and adhesion, thereby effectively improving production efficiency and product yield.

[0095] The description of the above embodiments is only used to help understand the method of the present disclosure and its core concept. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present disclosure, several improvements and modifications can be made to the present disclosure, and these improvements and modifications also fall within the protection scope of the claims of the present disclosure.