KR100218705B1 - Flame retardant copper laminate resin composition for automatic detection of fluorescence - Google Patents

Abstract

The present invention is a resin composition for flame retardant copper foil laminates for fluorescence detection type automatic visual inspection consisting of trifunctional epoxy resins, benzophenone-based or benzotriazole-based UV stabilizers, pyrazoline-based fluorescent dyes, curing agents and curing accelerators.

Description

Resin composition for flame retardant copper clad laminate for fluorescence detection method

The present invention relates to a method of manufacturing a high heat resistant copper clad laminate used for automatic visual inspection using a fluorescence detection method having ultraviolet shielding function and flame retardancy.

Thin copper core laminates used for multilayer circuit boards among copper foil laminates are formed through several processes to form multilayer circuit boards. Therefore, considerable thermal changes are made. Therefore, thin copper laminates for core materials It requires high heat resistance and high glass transition temperature as its characteristic value.

In the case of the lack of heat resistance, during the manufacture of multilayer printed circuit boards, the thermal phenomenon of copper laminates is caused by hot thermal lamination such as lead treatment (above 260 ℃), and the chip is mounted after completion of the circuit due to thermal expansion due to thermal change. The misalignment of the holes (Hole) causes a defect that becomes impossible to use.

In addition, there is a problem of introducing an automatic visual inspection device when inspecting a multilayer circuit board. In general, the automatic visual inspection method is divided into two types in the manufacturing process of a printed circuit board.

Conventional inspection method is applied to a method of inspecting the pattern of the circuit by detecting the intensity of the emitted light reflected by irradiating the white light on the substrate, which is applied when the light is irradiated after etching the substrate (Etching) It is based on the principle that light is strongly reflected on the metal surface and light is weakly reflected on the etched insulating layer.

However, since this method uses strong light, there is a high possibility of damage to the metal surface, and in the case of applying a resin for forming a circuit on the substrate or applying solderresist ink during the whole process to lead after etching. There is a disadvantage that the reflected light from the surface is strong and difficult to distinguish from the reflected light on the metal surface.

In particular, this method has a disadvantage in that inspection becomes poor as the back surface of the surface to be inspected reflects the copper circuit of the circuit as the substrate becomes thinner.

Therefore, in recent years, the automatic visual inspection method using fluorescence is gradually increasing, which is generated from organic materials such as image shape resin of insulating layer of copper foil laminate by irradiating light of low specific wavelength (generally 400 ~ 600nm) onto the substrate. It is a method of inspecting the appearance by detecting fluorescence of a specific wavelength.

In particular, this method is highly accurate and there is no problem appearing in the existing method is expected to use a lot of holiday, especially in the case of the copper clad laminate for the core material used in the multilayer board, the situation is absolutely required.

For the automatic visual inspection method of the fluorescence detection method, the insulating layer should have a function of displaying fluorescence. Since the detection method cannot be used with a conventional copper clad laminate, a special function should be given.

In addition, in order to prevent lead from soldering when forming a circuit when manufacturing a copper foil laminate for multilayer printed circuits, a photosensitive film or photosensitive ink is applied to a substrate and cured with ultraviolet rays. When the ultraviolet rays harden the photosensitive film or ink on the back surface through the base of the copper-clad laminate, there is a problem that causes an afterimage to form a residual image.

Therefore, in order to solve such a problem, a method of providing an ultraviolet shielding function to the photosensitive ink itself or a method of providing an ultraviolet shielding function to the substrate itself of the copper-clad laminate is used. The former method provides a function because the thickness of the ink is thin. In the case of a multilayer printed circuit board, the latter method is widely used because there is a disadvantage in that the effect is remarkably deteriorated.

As the latter method, a method of dispersing an inorganic filler (TiO ₂ ) is shown in Japanese Patent Application Laid-Open No. 2-219642. However, the method of dispersing such an inorganic filler becomes an opaque laminate, which is an inner layer of a copper clad laminate, and is rather irradiated by an inorganic filler. This scattering problem may occur.

As another method, a method of using a benzophenone-based or a benzotriazole-based ultraviolet stabilizer as a method of adding an ultraviolet stabilizer is disclosed in Japanese Patent Laid-Open No. 2-198189 and No. 63-289986, and alkyl thioxanthone -thioxanthone) is described in Japanese Patent Laid-Open No. 2-227442.

However, this method has only the effect of shielding ultraviolet rays below 400 nm, has no fluorescence effect, and has the disadvantage that the color of the copper clad laminate is significantly discolored.

Therefore, the present invention solves these problems, etc.

1) High Tg characteristics,

2) Fluorescence emitting function corresponding to automatic visual inspection device for fluorescence method,

3) UV shielding function

The present invention relates to the production of a resin composition used for producing a thin copper clad laminate used as a core material, especially for a high-functional copper clad laminate having the same.

Hereinafter, the present invention will be described in detail.

The present invention is 100 parts by weight of trifunctional epoxy resin, 0.1 to 4.0 parts by weight of benzophenone- or benzotriazole-based UV stabilizer, 0.005 to 3.0 parts by weight of parazoline-based fluorescent dye, 1.0 to 30 PHR of dicyanodiamide as a curing agent, as a curing accelerator. Resin composition for a flame-retardant copper foil laminate for fluorescence detection method characterized in that it consists of a catalytic amount of one or more mixtures selected from 2-methylimidazole, 2-ethyl-4-methylimidazole, benzoimidazole. It is about.

Hereinafter, the present invention will be described in more detail.

In the present invention, the trifunctional epoxy resin is represented by the following Structural Formula (II) and the epoxy equivalent is 200 to 700, which is a basic composition of the resin composition.

UV stabilizers include benzophenone and benzotriazole-based, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2 -Hydroxy-4-n-dodecyloxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2 Benzophenone-based ultraviolet absorbers such as -hydroxy-4-benzyloxybenzophenone, 2- (2-hydroxy-5'-methylphenyl) benzotriazole, and 2- (2-hydroxy-3,5-di-t -Butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'- It is used with benzotriazole type ultraviolet absorbers, such as t-butyl-5'-methylphenol) benzotriazole.

The amount used is 0.1 to 4.0 parts by weight based on 100 parts by weight of trifunctional epoxy resin. When it is less than 0.1, the UV shielding effect is insignificant. The color of the copper clad laminate laminate is deteriorated and the heat resistance is somewhat reduced.

It is also shown that the benzotriazole type is more suitable than the benzophenone type because of its good absorption of the magnetic beam at the wavelength of 300 to 400 nm.

Pyrazoline-based fluorescent dyes are compounds represented by the following structural formula (I)

In general, when irradiated with light of 400 ~ 650nm it emits less than 800nm fluorescence.

In particular, pyrazoline-based fluorescent dyes absorb ultraviolet rays in the ultraviolet region of 200-420 nm (maximum absorption wavelength 370 nm), so they are absorbed by benzophenone and benzotriazole (absorption wavelength: 400 nm or less, maximum absorption wavelength 350 nm or less). ) Shows the effect of shielding against ultraviolet rays, and also reinforces the existing absorption zone.

The amount used is 0.005 to 3.0 parts by weight based on 100 parts by weight of trifunctional epoxy resin. When using less than 0.005 parts by weight, the amount of fluorescent light emission may be small, causing an error. There is a problem that the physical properties of the copper-clad laminate, such as a large rise and the heat resistance is reduced as the fluorescent material is added.

Curing agent uses dicyanoodiamide (Dicyanodiamide) 1.0 ~ 30PHR. When using less than 1.0PHR, the amount of hardening agent is small, so that the hardening is not complete, the physical properties are significantly lowered. Since the agent remains in the state of a monomer, there is a disadvantage in that physical properties are lowered rather than using an appropriate amount of a curing agent.

The hardening accelerator is used alone or in combination of 2-methylimidazole, 2-ethyl-4-methylimidazole and benzimidazole which are imidazole-based curing accelerators, and a catalytic amount is used.

Since it is a curing accelerator to promote the reaction, it can be controlled according to the manufacturing conditions of the copper-clad laminate, and when using too much, it is difficult to control the reaction, and the cost of the curing agent hinders the reaction and the cost is increased.

The effect of the present invention is to give a fluorescent light emitting function to the existing FR-4 for the flame-retardant printed circuit by manufacturing a copper-clad laminate that can be used for automatic appearance inspection using fluorescence and applied to automatic appearance inspection printed circuit board Increasing the inspection efficiency, it has the effect of reducing the defect rate of the printed circuit board, improving the productivity by shortening the inspection time, and making it possible to inspect what was difficult in the automatic external inspection method using conventional light reflection. By giving the function, the ultraviolet ray reaches the back side when curing the solder ink using ultraviolet rays, and it has the effect of UV shielding copper clad laminate to remove the afterimage defect caused by curing the part outside the circuit as well as the existing benzophenone And ultraviolet light not shielded from benzotriazole By extensively shielding the station it may have the effect of amplifying the function.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by Examples.

Example 1

2.5 g of dicyanodiamide was added to 20 g of N, N'-dimethylformamide and completely dissolved. 0.15 g of 2-methylimidazole and 15 g of methyl cellosolve were added thereto, followed by stirring to completely dissolve it. )

0.2 g of 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) benzotriazole (Tinubin 326, Ciba-Geigy Co., Ltd.), an ultraviolet stabilizer, and Neo Super HR-21 (a fluorescent dye) 0.05 g of Japan Central Synthetic Chemicals) was completely dissolved in 20 g of acetone. (Solution 2)

After adding (Solution 2) to (Solution 1) for 10 minutes, adding 100g of VG3101M80 trifunctional epoxy resin (Epoxy equivalent 210, Nippon Samjung Petrochemical Co., Ltd.) and stirring until thoroughly mixed. Was prepared.

The resin composition prepared as described above was impregnated into glass fibers and then dried by hot air to prepare a prepreg having a resin content of 43% by weight. After laminating two sheets of prepreg, copper foil having a thickness of 18 μm was placed on both sides, and then laminated. Then, a press was heated and pressurized at a temperature of 180 ° C. and 40 kg / cm 2 for 90 minutes and pressurized to prepare a copper foil laminated plate having a thickness of 0.4 nm. . After etching the copper-clad laminate using an etching solution, the amount of fluorescence was measured by using the OPTROTECH (USA) VISION-206 automatic visual inspection device. The UV shielding rate was high-pressure mercury lamp (wavelength 300-400nm, 1kW). Was irradiated with a light amount of 700 mj and the degree of transmission thereof was measured with a photometer.

Example 2

Neo Super HR-21 of (Solution 2) of Example 1 was used in an amount of 0.1 g instead of 0.05 g.

Example 3

Neo Super HR-21 of (Solution) of Example 1 was increased to 0.2 g instead of 0.05 g, and the other procedures were carried out in the same manner.

Example 4

Instead of 0.2 g of Tinuvin 326 of Example 1 (Solution 2), the amount was increased to 0.4 g, and the other procedures were carried out in the same manner.

Comparative Example 1

YDB424A80 (Epoxy equivalent 400, Kukdo Chemical Co., Ltd.) was used in place of the VG3101M80 resin of Example 1, and the other procedures were carried out in the same manner.

Comparative Example 2

Other than (Solution 2) of Example 1 was carried out in the same manner.

Comparative Example 3

In the solution 2 of Example 1, except that Neo Neo HR-21 was not used, the same procedure was followed.

[result]

※ Ref. : Minimum Testable Fluorescence (Standard: ORBOTTECH Reference Material)

※ UV transmittance = (ultraviolet light quantity with copper clad laminate / ultraviolet light without copper clad laminate) × 100

Claims (2)

100 parts by weight of the trifunctional epoxy resin, 0.1 to 4.0 parts by weight of a benzophenone-based or benzotriazole-based ultraviolet stabilizer, 0.005-3.0 parts by weight of a pyrazoline-based fluorescent dye represented by the following structural formula (1), and 1.0 to dicyanodiamide as a curing agent. 30PHR, flame-retardant copper foil for automatic detection of fluorescence detection method characterized in that it consists of a catalytic amount of one or two or more mixtures selected from 2-methylimidazole, 2-ethyl-4-methyl imidazole and benzimidazole as a curing accelerator. Resin composition for laminated boards. The resin composition according to claim 1, wherein the trifunctional epoxy resin is represented by the following Structural Formula (II) and has an epoxy equivalent of 200 to 700.