KR19980084866A - Acrylic copolymer resin used in the photosensitive liquid composition for printed circuit board (PCB) and its manufacturing method - Google Patents

Abstract

The present invention relates to an acrylic copolymer resin used in a photoresist composition for an ultra-precision pattern printed circuit board and a method for manufacturing the same. More particularly, the present invention is used as a main resin of the photoresist composition to adhere to the surface of the photosensitive layer when the base film is removed. On the contrary, the metal surface of the PCB relates to a novel acrylic copolymer resin represented by the following Chemical Formula 1 showing a strong adhesive strength and a method of manufacturing the same.

[Formula 1]

In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, preferably 0.6 to 0.65, m is 0.1 to 0.4, preferably 0.2 to 0.3, x + y is 0.1 or less, and the mixing ratio of x: y is 2-3: 1.

Description

Acrylic copolymer resin used in the photosensitive liquid composition for printed circuit board (PCB) and its manufacturing method

The present invention relates to an acrylic copolymer resin used in a photosensitive liquid composition for an ultra-precision pattern printed circuit board (hereinafter referred to as a PCB) and a method of manufacturing the same, and more particularly, to a main resin of the photosensitive liquid composition. It relates to a novel acrylic copolymer resin represented by 1 and a preparation method thereof. As used herein, the term photoresist is used in the same sense as the photosensitive agent.

[Formula 1]

In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, preferably 0.6 to 0.65, m is 0.1 to 0.4, preferably 0.2 to 0.3, x + y is 0.1 or less, and the mixing ratio of x: y is 2-3: 1.

As ultra-precise patterning of PCBs is rapidly progressed due to the rapid rise of micro- and ultra-thin electronic products, dry films coated with a transparent film on a transparent film and dried to achieve ultra-precision patterns have been used. However, as the dry film used so far, the limit has been reached.

Until now, the ultra-precision pattern could be achieved by at least thinning the coating thickness, but there has been a lot of inconveniences due to the condition of the PCB depending on the coating method. For example, in the dipping method of depositing a liquid photosensitive component, 1. Non-uniformity of upper and lower coating thickness, 2. Unavailability of through-hole PCB board, and 3. Drying The problem of solvent odor and human toxicity is the problem of avoiding work, and it is not general supply and there is no general use. Second, it is the coating of PCB board by roller coating W / C. The problem of automation, 2. Excessive facility cost and location, and 3. Drying problem have not been spread yet. Third, the silk screen method is only partially distributed under similar conditions as the second.

On the other hand, in general, a dry film is prepared by coating a photoresist on a base film, and then drying and coating one side (base film relative surface) of the photoresist with a protective film. Looking at the manufacturing method of the conventional PCB substrate using such a dry film, after removing the protective film of the dry film, the photosensitive liquid surface is laminated on the metal plate, and thermal transfer. Then, the mask film is placed on the base film, and then proceeds in the order of exposure-removal of base film-development.

As such, conventionally, the base film is removed after the exposure, because the surface of the photosensitive layer is still sticky, and thus there is a risk that the mask film may stick and cause contamination and damage. Therefore, there is a disadvantage in that the resolution is reduced by about 20 μm when exposed without removing the base film (eg, PET film) having a thickness of about 20 μm used in the dry film. In conclusion, the removal of the base film is essential in order to increase the resolution, and in order to remove the base film, it should not be adhered when the mask film is peeled off, and a photoresist having excellent adhesion with a metal substrate is required.

In accordance with this demand, the present inventors have conducted extensive research, and have developed an acrylic copolymer resin that exhibits excellent adhesion on a PCB and does not adhere to a mask film, and the present invention has been completed based thereon.

Accordingly, an object of the present invention is to provide an acrylic copolymer resin that is used as a main resin of a photoresist composition for ultra-precision pattern circuit boards, which does not have a disadvantage in that a mask film is adhered to the surface of a photosensitive layer and, on the contrary, exhibits strong adhesive strength on a metal surface of a PCB. have.

Another object of the present invention to provide a method for producing the acrylic copolymer resin.

Acrylic copolymer resin of the present invention for achieving the above object is represented by the following formula (1).

[Formula 1]

In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, preferably 0.6 to 0.65, m is 0.1 to 0.4, preferably 0.2 to 0.3, x + y is 0.1 or less, and the mixing ratio of x: y is 2-3: 1.

The production method of the present invention for achieving the above another object is 0.5 to 0.8 mole of methyl methacrylate (MMA), 0.1 to 0.4 mole of methacrylic acid (MAA), 2-hexylethyl methacrylate on the basis of 1 mole in the presence of a polymerization catalyst (2-HEAM) 0.05 to 0.09 mol and 0.025 to 0.04 mol of isobutyl methacrylate are polymerized, and then 5 to 15 parts by weight of triethylene glycol diacetate is added to 100 parts by weight of the resin solid as a plasticizer. .

Looking at the present invention in more detail as follows.

The acrylic copolymer resin of the present invention is represented by the following Chemical Formula 1, and is a copolymer resin containing methyl methacryl ester and methacrylic acid having chemically active hydrogen. The copolymer resin is used as a main resin of the photosensitive liquid composition, and thus, there is no disadvantage of sticking to the surface of the photosensitive layer when the mask film is peeled off, and on the contrary, the copolymer resin has physical and chemical properties showing strong adhesive strength on the metal surface of the PCB. In addition, it is acid resistant and exhibits strong corrosion-resistant properties.

[Formula 1]

In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, preferably 0.6 to 0.65, m is 0.1 to 0.4, preferably 0.2 to 0.3, x + y is 0.1 or less, and the mixing ratio of x: y is 2-3: 1.

For reference, the photosensitive liquid composition comprising the acrylic copolymer resin represented by Chemical Formula 1 has been filed under the same name of the present invention by the applicant of the photosensitive liquid composition for a high precision pattern printed circuit board (PCB) and a developing method using the same. The contents of the patent are included in the present invention.

The acrylic copolymer resin according to the present invention is 0.5 to 0.8 mol of methyl methacrylate (MMA), 0.1 to 0.4 mol of methacrylic acid (MAA) and 0.05 to 0.09 mol of 2-hexylethyl methacrylate (2-HEAM) on a molar basis. And 0.025 to 0.04 moles of isobutyl methacrylate.

The amount of the methyl methacrylate used is 0.5 to 0.8 moles, preferably 0.6 to 0.65 moles, based on 1 mole, and when the amount is less than 0.5 moles, the resin becomes soft, causing adhesion of the mask film. Hardened and photocured resins have problems with adhesion.

The amount of the methacrylic acid used is 0.1 to 0.4 moles, preferably 0.2 to 0.3 moles on a molar basis, and less than 0.1 moles leads to poor development, and when the molar excess exceeds 0.4 moles, etching is caused by penetration of the developer into the photocured resin. It is poor and there is a problem in resolution.

The amount of the 2-hexylethyl methacrylate is preferably 0.05 to 0.09 mol based on 1 mol, and the amount of isobutyl methacrylate is preferably 0.025 to 0.04 mol based on 1 mol.

The total mole number of 2-hexylethyl methacrylate and isobutyl methacrylate used in the present invention is preferably less than 0.1 mole based on 1 mole, and when exceeded, the physical properties of the resin decrease and cause contamination of the mask film. Moreover, as for the mixing molar ratio of the said 2-hexyl ethyl methacrylate and isobutyl methacrylate, 2-3: 1 are preferable.

On the other hand, the process according to the invention is carried out in the presence of a polymerization catalyst, a preferred polymerization catalyst is azobisisobutyronitrile (AIBN). In addition, triethylene glycol diacetate is used as a plasticizer, and 5-15 weight part is used with respect to 100 weight part of resin solid content. At this time, when less than 5 parts by weight, the resin is hardened to degrade adhesiveness, and when it exceeds 15 parts by weight, the adhesiveness rises, causing damage to the mist film.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following examples.

Example 1

Methyl methacrylate (MMA) 185 parts (1.85 mole)

Methacrylic acid (MAA) 62.5 parts (0.726 mole)

45 parts (0.227 mole) of 2-hexylethyl methacrylate (2-HEAM)

Isobutyl methacrylate (IBMA) 5 parts (0.035 mole)

The above ingredients are placed in a four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer, and diluted with 450 parts of methyl ethyl ketone (MEK), followed by stirring by heating. Separately, about one third of the polymerization catalyst solution in which 1.5 parts of azobisisobutyronitrile (AIBN) was mixed and dissolved in 50 parts of MEK was added to the flask, and the stirring was continued. When the temperature of the contents reached 70 ° C, the heating was stopped. 2/3 of the catalyst solution is added dropwise over 2 hours. It raises to 89 degreeC by internal heat of reaction, and a solvent refluxs. After completion of the dropwise addition, the reaction was continued for 3 hours at 89 ° C, and stirring was continued until the temperature reached room temperature. 15 parts of triethylene glycol diacetate was added thereto and mixed well to prepare an acrylic copolymer resin represented by Chemical Formula 1.

Example 2

The composition of Example 1 was changed as follows, except that a resin solution was prepared.

Methyl methacrylate (MMA) 200 parts (2 mole)

Methacrylic acid (MAA) 49 parts (0.568 mole)

45 parts (0.227 mole) of 2-hexylethyl methacrylate (2-HEAM)

Isobutyl methacrylate (IBMA) 5 parts (0.035 mole)

Example 3

The composition of Example 1 was changed as follows, except that a resin solution was prepared.

Methyl methacrylate (MMA) 172.5 parts (1.725 mole)

Methacrylic acid (MAA) 73 parts (0.851 mole)

45 parts (0.227 mole) of 2-hexylethyl methacrylate (2-HEAM)

Isobutyl methacrylate (IBMA) 5 parts (0.035 mole)

Application Examples 1 to 3

100 parts of the acrylic copolymer resin of Examples 1 to 3

Pentaerythritol triacrylate 40 parts

Irga Cure 369 from Shiba-Geigi, part 16

Loika's Crystal Violet Part 6

2,2-dichloroacetophenone 6 parts

Tong Yang Orient Chemical, Oil Blue Ⅱ N 0.25

Iribaox 1010 from Shiba-Geigi

Mix the mixture with ethyl cellosolve (EC) and MEK to make 500 parts in total. 50㎛ the thickness of the liquid after drying, the coating thickness of 15㎛ to the COMA coater on a PET film of 20㎛ thickness. This was attached to the PCB at a roller temperature of 120 DEG C, a pressure of 5 kg / cm < 2 >, and a speed of 1.5 to 2.0 m / min in a normal laminator, and then immediately peeled off the upper PET film. After cooling, exposure-development treatment was performed to compare the development degree with the conventional dry film.

Treatment with an exposure dose of 60 mJ / cm 2 and a 1% Na ₂ CO ₃ solution resulted in 100% reproduction of the PCB circuit having a line width of 30 μm, while 50% reproduction of the conventional dry film. The number of moles of MAA and the thickness of the cured film according to the treatment time of the 1% Na ₂ CO ₃ solution and the thickness of the photoresist layer preferred for application are shown in Table 1 below.

TABLE 1

Example Mole of MAA (based on 1 mole%) Development time at 25 ° C with 1% Na ₂ CO ₃ solution Cured film state Remarks Example 1 0.25 1 minute Great Excellent for 10-20㎛ coating Example 2 0.20 1 minute 30 seconds ″ Excellent for 5-10㎛ coating Example 3 0.30 40 seconds ″ Excellent for 30 ~ 40㎛ coating

As described above, the acrylic copolymer resin according to the present invention does not have the disadvantage that the mask film is adhered to the surface of the photosensitive layer, and on the contrary, exhibits a strong adhesive strength on the PCB metal surface. Therefore, the dry film containing the resin can be exposed and developed after removing the base film, the resolution is improved by the thickness of the base film, thereby developing a high-precision printed circuit board without the need for a new facility. . In addition, there is an effect that the coating thickness can be adjusted according to the needs of the product to the desired level.

Claims (4)

Acrylic copolymer resin used in the photosensitive liquid composition for a printed circuit board (PCB) represented by the formula (1). [Formula 1] In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, m is 0.1 to 0.4, and x + y is 0.1 or less, and the mixed molar ratio of x: y is 2 to 3: 1 0.5 to 0.8 mole of methyl methacrylate (MMA), 0.1 to 0.4 mole of methacrylic acid (MAA), 0.05 to 0.09 mole of 2-hexylethyl methacrylate (2-HEAM) in the presence of a polymerization catalyst, and isobutyl meta Printed circuit board represented by the following formula (1) characterized by polymerizing the acrylate 0.025-0.04 moles and then adding 5-15 parts by weight of triethylene glycol diacetate as a plasticizer with respect to 100 parts by weight of the resin solids (PCB) Method for producing an acrylic copolymer resin used in the photosensitive liquid composition for). [Formula 1] In the above formula, n, m, x and y are the moles of each component, when n + m + x + y is 1, n is 0.5 to 0.8, m is 0.1 to 0.4, and x + y is 0.1 or less, and the mixed molar ratio of x: y is 2 to 3: 1 The method of claim 2, wherein the amount of the methyl methacrylate (MMA) is 0.6 to 0.65 moles based on 1 mole of a method for producing an acrylic copolymer resin used in the photosensitive liquid composition for a printed circuit board (PCB). The method of claim 2, wherein the amount of the methacrylic acid (MAA) is 0.2 to 0.3 mole based on 1 mole of the acrylic copolymer resin used in the photosensitive liquid composition for printed circuit board (PCB).