KR101115162B1 - Film type transfer material - Google Patents

Abstract

The present invention provides a film-type photosensitive transfer material comprising a base film, a resin protective layer, a photosensitive resin layer and a protective film, wherein the adhesive force of the resin protective layer is 0.005 kgf / cm 2 or less, which can be applied to a printed circuit board. In this case, the exposure can be performed with the base film removed, so that the gap between the mask and the photosensitive resin layer can be narrowed during exposure, thereby improving the resolution of the pattern and even removing the base film before the exposure process. It is possible to work in the form or apply to a roll to roll process.

Film-type photosensitive transfer material, resin protective layer

Description

Film-type photosensitive transfer material

The present invention relates to a film-type photosensitive transfer material.

In general, as a film-type photosensitive transfer material, a dry film form (hereinafter, referred to as a 'dry film photoresist') is typically used.

Dry film photoresists are used for printed wiring boards, printed circuit boards, IC packaging, metal relief phase formation, and the like, and generally include a base film, a photosensitive resin layer, and a protective film.

The base film serves as a support for the photosensitive resin layer to facilitate handling during exposure of the photosensitive resin layer having adhesive force. The photosensitive resin layer is manufactured to suit the purpose, including, for example, a photopolymerizable monomer, a photopolymerization initiator, a binder polymer, and the like. On the other hand, the protective film is formed on the surface where the base film of the photosensitive resin layer is not formed may serve to prevent damage to the photosensitive resin layer.

As an example of a pattern forming method using such a dry film photoresist, for example in manufacturing a printed circuit board, the protective film is first peeled off and laminated on a copper clad laminate (CCL), and then a mask having a desired pattern is applied. Exposing through irradiation with ultraviolet (UV) light, and developing (developing) the uncured portion using a suitable solvent. Typically, exposure is performed with the base film 40 attached to the photosensitive resin layer 20, as shown in FIG. 3, in which case the photosensitive resin layer 20 and the mask 60 are attached to the base film 40. Since it is spaced apart by the thickness of, as a result, the degradation of the resolution may occur. This may be exposed after peeling off the base film, but in general, the photosensitive resin layer has adhesiveness, and when the base film is peeled off, the mask adheres to the photosensitive resin layer, thereby damaging the photosensitive resin layer, and consequently, the resolution decreases. do. Therefore, in reality, the exposure after peeling off the base film is difficult to be achieved, and thus the problem of deterioration of resolution remains.

Furthermore, as the density of printed circuit boards increases and the density of circuit lines increases with the development of semiconductor packaging technology, there is an urgent need for a high resolution film-type photosensitive transfer material that can be applied to such a fine circuit board.

 Accordingly, the present invention is to provide a film-type photosensitive transfer material capable of removing the base film and exposure.

In addition, the present invention is to provide a film-type photosensitive transfer material that can increase the resolution by minimizing the gap between the mask and the photosensitive resin layer during exposure, and a substrate for a display element formed with a pattern.

In one embodiment of the present invention includes a base film, a resin protective layer, a photosensitive resin layer and a protective film; The resin protective layer is defined as the force per unit area required to peel off the base film, laminate a separate PET film on the resin protective layer, and then begin to release it to release from 5 cm to 8 cm from the starting point. Provided is a film-type photosensitive transfer material having an adhesive force of 0.005 kgf / cm 2 or less.

In the film type photosensitive transfer material according to the embodiment of the present invention, the resin protective layer may be an alkali developable polymer layer.

In the film type photosensitive transfer material according to an embodiment of the present invention, the resin protective layer may be a solubility of 5 g or less in methyl ethyl ketone solution at 25 ℃ defined as follows.

Solubility: Add 50 g of a resin protective layer to 100 g of methyl ethyl ketone, stir at 25 ° C. for 1 hour, filter with filter paper, and measure the weight of the resin protective layer remaining on the filter paper to define a reduction in the weight of the resin protective layer.

In the film-type photosensitive transfer material according to an embodiment of the present invention, the resin protective layer may be formed from a coating liquid containing a water-soluble polymer having a weight average molecular weight of 5,000 to 300,000.

In the film-type photosensitive transfer material according to an embodiment of the present invention, the release force of the protective film and the photosensitive resin layer may be less than the release force of the base film and the resin protective layer.

In addition, the resin protective layer may be a thickness of 0.001 ~ 10㎛.

In the film-type photosensitive transfer material according to a preferred embodiment of the present invention, the resin protective layer may be a change in adhesion force of 5000% or less represented by the following equation (1).

Equation 1

In the above formula, the first adhesive force is the force per unit area required to release a separate PET film on the resin protective layer immediately after peeling off the base film, and then start to release the mold from 5 cm to 8 cm from the starting point. The second adhesive force is defined, and the second adhesive force is peeled off and left for 240 hours under a temperature of 25 ° C. and a humidity of 50%, and then a separate PET film is laminated on the resin protective layer and then released to release from 5 cm from the starting point. It is defined as the force per unit area required to release up to 8 cm.

In the film-type photosensitive transfer material according to a preferred embodiment of the present invention, the resin protective layer may be a polyvinyl alcohol-based resin layer. In this case, the resin protective layer may include at least one or more additives selected from a wetting agent, a leveling agent, an antifoaming agent, an adhesive, and an adhesive.

In the film-type photosensitive transfer material according to an embodiment of the present invention, the protective film may be a polyester film with or without a release layer.

In the film type photosensitive transfer material according to an embodiment of the present invention, the base film may be a polyester film with or without a release layer.

An exemplary embodiment of the present invention provides a display device substrate having a pattern formed by using the film-type photosensitive transfer material described above.

The film-type photosensitive transfer material of the present invention is a film-type photosensitive transfer material and a display element substrate that can further improve the resolution of the pattern by narrowing the distance to the photosensitive resin layer during exposure as the base film is peeled off and then exposed. Can provide.

In addition, the present invention can provide a film-type photosensitive transfer material that can be peeled off the base film prior to exposure and can be applied in a sheet unit or applied to a roll to roll process without damaging the photosensitive resin layer.

In addition, since the present invention removes the base film and the exposure process is performed immediately, the conventional process of removing the base film after performing the foreign material removal process after the exposure process can be simplified, and the manufacturing cost of the display device substrate can be reduced. Can be.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail with reference to the accompanying drawings.

1 shows an embodiment of the film-type photosensitive transfer material of the present invention. The film-type photosensitive transfer material of the present invention has a structure including a protective film 10, a photosensitive resin layer 20, a resin protective layer 30, and a base film 40.

Although not shown in FIG. 1, the protective film 10 and / or the base film 40 may include a release layer on at least one surface thereof.

2 is a cross-sectional view of a laminated structure during exposure of a substrate for a display device to which a film type photosensitive transfer material of the present invention is applied. Such a film-type photosensitive transfer material of the present invention, when applied to a display device substrate such as a printed wiring board, a printed circuit board, peeling off the protective film 10 and laminating the dry film so that the photosensitive resin layer is on the copper-clad laminate 50. After the base film 40 is peeled off, the mask is placed on the resin protective layer, subjected to an exposure process, and then subjected to a development process.

Hereinafter, each layer is explained in full detail.

<Base film>

Since the base film of the present invention serves as a support for the resin protective layer and the photosensitive resin layer, it is preferable to have sufficient mechanical properties. Suitable materials for the base film include polyester film such as polyethylene terephthalate or polyethylene naphthalate, polyethylene, polypropylene, polyimide, polyamide, cellulose triacetate, cellulose diacetate, alkylpoly (meth) acrylate, ( Meth) acrylic acid ester copolymers, copolymers of polyvinylchloride and vinyl acetate, polytetrafluoroethylene and polytrifluoroethylene, and the like, and polyethylene terephthalate is particularly preferred. The thickness of a base film is the range of 10-100 micrometers, Preferably it is 15-30 micrometers, but it is not limited to this.

According to the resin protective layer composition to be described later may be a base film including a release layer for controlling the release property. At this time, the method and specific composition of the formation of the release layer is not particularly limited, but damage to the resin protective layer while satisfying the degree that the release force between the base film and the resin protective layer is higher than the release force between the protective film and the photosensitive resin layer. It is sufficient to be able to satisfy the surface properties to the extent that can be prevented.

<Resin protective layer>

The resin protective layer is positioned between the base film and the photosensitive resin layer, and the film-type photosensitive transfer material according to one embodiment of the present invention including such a resin protective layer is masked on the resin protective layer after peeling off the base film during exposure. The exposure can be carried out with.

Therefore, the resin protective layer should be easily released from the base film and should not stick to the mask. In addition, it is required to have a low adhesive strength so that no defects occur even when the resin protective layers are laminated or the copper-clad laminate and the resin protective layer are in contact with each other during sheet-based work or roll-to-roll operation after exposure.

In particular, it is important that the resin protective layer does not stick to the mask when the base film is peeled off and then exposed in a state where the resin protective layer is exposed. In this case, the mask may mainly use polyethylene terephthalate (PET), glass substrate (glass), etc., and thus the resin protective layer of the present invention is easily peeled off after re-laminating the polyethylene terephthalate film after peeling the base film. It should be possible.

In this regard, the resin protective layer of the present invention peels off the base film, and then laminates a separate PET film on the resin protective layer and starts to release it, per unit area required to release from 5 cm to 8 cm from the starting point. It is preferable that the adhesive force defined by force is 0.005 kgf / cm <2> or less. A specific method of measuring the adhesive force was to remove the protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm, laminating the copper clad laminate at 110 ° C and 4 kgf / cm 2 at a speed of 2 m / min, and then removing the base film. Remove Here, after laminating a PET film having a width of 4 cm, a length of 25 cm, and a thickness of 19 μm at a speed of 2 m / min under conditions of 110 ° C. and 4 kgf / cm 2, the PET film was started to be released from the point 5 cm from the starting point. The force per unit area required to release to the point of 8 cm is measured using a universal tensile tester.

When the adhesive force obtained by such a measuring method is larger than 0.005kgf / cm 2, release is not easy and tearing occurs when contacting the mask passes, and thus it is difficult to obtain an advantageous effect due to exposure after removing the base film.

On the other hand, the resin protective layer should be able to block the oxygen inhibiting the polymerization reaction of the photosensitive resin layer during exposure, it is preferable that can be removed together in the development process after the exposure process.

In consideration of this point, it may be preferable that the resin protective layer is an alkali developable polymer layer. As used herein, the term " alkali developable type " will be understood to mean a property developed by an alkaline solution such as Na 2 CO 3, NaOH or KOH at a low concentration.

In consideration of this point, the resin protective layer is a water-soluble salt of polyvinyl ether maleic anhydride, a water-soluble salt of cellulose ether, a water-soluble salt of carboxyalkyl cellulose, a carboxyl alkyl starch water-soluble salt, polyvinyl alcohol, polyvinylpyrrolidone, poly It may be formed from a composition containing water-soluble polymers such as acrylamide, water-soluble salts of polyamide, water-soluble salts of polyacrylic acid, polyethylene glycol, polypropylene glycol, gelatin, ethylene oxide polymer, starch and the like.

In particular, since the viscosity of the composition for forming a resin protective layer affects the physical properties of the coating layer, and the viscosity is also affected by the degree of polymerization of the polymer, the weight average molecular weight of the polymer in the composition is preferably 5,000 to 300,000. If the weight average molecular weight is less than 5000, the coating on the film becomes difficult, and the strength is weak, so that it is difficult to perform the protective function of the photosensitive resin layer, and if the weight average molecular weight exceeds 300,000, the development time is long and after lamination on the copper clad laminate There is a risk of damage when peeling the base film.

In addition, in the film type photosensitive transfer material according to the preferred embodiment of the present invention, the resin protective layer has a solubility of 5 g or less in methyl ethyl ketone solution at 25 ° C. in the distribution process of components between the photosensitive resin layer and the resin protective layer ( It may be desirable in terms of preventing diffusion and ultimately extending the shelf life of the product.

Herein, the solubility in methyl ethyl ketone solution was specifically, 50 g of a resin protective layer was added to 100 g of methyl ethyl ketone, stirred at 25 ° C. for 1 hour, filtered through a filter paper, and then the weight of the resin protective layer remaining on the filter paper was measured. It is defined as the amount of reduction of the resin protective layer weight.

Meanwhile, as described above, in the case of the film-type photosensitive transfer material according to the exemplary embodiment of the present invention, the exposure process may be performed after removing the base film in a later process, in which case a predetermined time may be required before entering the exposure process. In this case, the resin protective layer absorbs moisture when exposed to the external environment, and may cause a change in physical properties. In consideration of this point, in the film type photosensitive transfer material according to the preferred embodiment of the present invention, the resin protective layer may preferably have an adhesive change rate of 5000% or less represented by Equation 1 below.

Equation 1

In the above formula, the first adhesive force is the force per unit area required to release a separate PET film on the resin protective layer immediately after peeling off the base film, and then start to release the mold from 5 cm to 8 cm from the starting point. After the base film is peeled off and left for 10 days at 25 ° C. and 50% humidity conditions, the second adhesive force is laminated to a separate PET film on the resin protective layer, and then starts to release it, starting from 5 cm from the starting point. It is defined as the force per unit area required to release to the point cm.

Considering the above aspect, the preferred resin protective layer may be a polyvinyl alcohol-based resin layer. Here, the polyvinyl alcohol-based resin layer will be understood as a resin layer in which the polyvinyl alcohol-based resin occupies at least 10% by weight or more of the composition for forming the resin layer.

When the resin protective layer is a polyvinyl alcohol-based resin layer, the coatability may vary depending on the base film, and may further include a wetting agent in consideration of this.

In addition, depending on the selection of the base film and the protective film to be described later it may be necessary to control the release force, even in this case, additives that can control the release property, for example, wetting agent (leveling agent), leveling agent (defoamer), adhesive and At least one additive selected from the pressure-sensitive adhesives may be included.

There is no particular limitation on such additives, and as described above, any additive capable of controlling the release force between the protective film and the photosensitive resin layer to a small extent as compared with the release force between the base film and the resin protective layer may be used.

It does not specifically limit as a method of forming such a resin protective layer, The composition for resin protective layer formation can be melt | dissolved in the organic solvent and water, Preferably water, and can apply | coat and dry on a base film, and can form.

Since the exposure process is performed in a state where the resin protective layer is formed, the thickness of the resin protective layer is better to increase the resolution, and preferably 0.001 to 10 μm.

<Photosensitive resin layer>

The photosensitive resin layer composition is generally composed of a binder polymer, a photopolymerizable monomer, a photoinitiator, and other additives, and may be variably formed according to the characteristics and characteristics of the printed circuit board.

The method of forming the photosensitive resin layer in contact with the resin protective layer is not particularly limited, but a method of applying the photosensitive resin layer on the protective film and bonding the resin protective layer formed on the base film may be advantageous.

The thickness of the photosensitive resin layer may be generally 10 to 100 μm depending on the type of the printed circuit board.

<Protective Film>

As a protective film, a suitable release property is required so that a film-type transfer material is easily detached when applied to a post process and is not released when stored and distributed.

In view of the method of producing a film-type photosensitive transfer material by applying a photosensitive resin layer to a protective film and then laminating with a resin protective layer formed on a base film, the protective film is considered in view of the applicability of the photosensitive resin layer. It is preferable that it is a polyester film. In particular, considering the release property, it may be preferable that the polyester film including a release layer. An example of the release layer may be a method of coating or igniting silicon, but is not limited thereto. As described above, as long as the release force between the protective film and the photosensitive resin layer is small compared with the release force between the base film and the resin protective layer and does not impair the surface properties of the photosensitive resin layer, formation of the release layer is particularly limited in the method and composition. This is not the case.

If a resin protective layer is formed on the base film, the photosensitive resin layer is applied on the resin protective layer, and the protective film is finally laminated, a polyolefin film having a thickness of 15 to 25 μm may also be preferable as a protective film.

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

&Lt; Example 1 >

(a) Methacrylic acid (Acthacrylic acid): Acrylic acid (Acrylc acid): Methyl methacrylate (Methylmethacrylate: MAA) using a weight ratio of 20:10:70 (weight average molecular weight 70,000, solid content 50%), solvent MEK, An acrylic acid polymer was prepared by polymerization under conditions of a polymerization initiator AIBN of 1%, a reaction temperature of 80 ° C., a reaction time of 4 hours, and a post initiator AIBN of 3%.

(b) diluting the acrylic acid polymer to 200 cps with methyl ethyl ketone to obtain a composition for a resin protective layer, coating it on a 20 μm thick base film (OPP) using a coating bar and drying at 80 ° C. for 10 minutes using a hot air oven. A resin protective layer having a thickness of 2 μm was formed.

(c) A photosensitive resin composition was prepared in the composition and content used for UH-9200 series (Kolon). Specifically, the photoinitiators were dissolved in methyl ethyl ketone and methyl alcohol as solvents, and then photopolymerizable oligomers and binder polymers were added and mixed for 1 hour using a mechanical stirrer to prepare a photosensitive resin composition.

(d) The photosensitive resin composition was coated on a 20 μm thick protective film (OPP) using a coating bar and then dried at 80 ° C. for 6 minutes using a hot air oven to form a photosensitive resin layer having a thickness of 15 μm.

(e) film-sensitive photosensitive film having a thickness of 57 μm in the form as shown in FIG. 1 by laminating at a pressure of 4 kgf / cm 2 at 50 ° C. such that the dried photosensitive resin layer of the film of (d) and the resin protective layer of (b) contact each other. A transfer material was prepared.

<Example 2>

A film-type photosensitive transfer material having a thickness of 57 μm was obtained in the same manner as in Example 1, except that polyethylene glycol (manufacturer: Sigma-Aldrich, weight average molecular weight 20,000) was diluted to 200 cps with secondary distilled water as a resin protective layer composition. Prepared.

<Example 3>

A film-type photosensitive transfer material having a thickness of 55.5 μm was prepared in the same manner as in Example 1, except that the composition for resin protective layer of Example 1 was coated with 0.5 μm.

<Example 4>

A film-type photosensitive transfer material having a thickness of 56 μm was manufactured in the same manner as in Example 1, except that a polyethylene terephthalate film (thickness 19 μm, CY201-19um, KOLON), instead of OPP, was used as a protective film. It was.

Comparative Example 1

A photosensitive resin composition was prepared using the composition and content used in the UH-9200 series (manufactured by Kolon), coated on a 19 μm-thick PET film (FDFR, Kolon) using a coating bar, and then heated to 80 ° C. using a hot air oven. It dried for 6 minutes at and formed the photosensitive resin layer of thickness 15micrometer. The dried film was laminated with a polyester film (23 μm) at 4 kgf / cm 2 at 25 ° C. to prepare a film type photosensitive transfer material having a thickness of 57 μm.

The release force, adhesive force, and adhesive force change rate of the film-type photosensitive transfer material prepared according to Examples and Comparative Examples were measured as follows, and the results are shown in Table 1 below.

(1) release force

<Protective Film>

While releasing the protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm, the universal testing machine (UTM, 4303 series, Instron Co., Ltd.) Measured using.

<Base film>

After removing the protective film of the film-type photosensitive transfer material specimen of 3cm in width, 20cm in length, it was laminated on the copper clad laminate at 110 ° C. at a speed of 2 m / min and a pressure of 4 kgf / cm 2. Then, the force per unit area required for releasing the base film from 5 cm to 8 cm from the starting point while releasing the base film was measured using UTM (4303 series, Instron).

(2) adhesion

The protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm was removed, and the base film was removed after laminating the copper-clad laminate at 110 ° C. and 4 kgf / cm 2 at a speed of 2 m / min. After laminating a 4 cm wide, 25 cm long, 19 μm thick PET film (FDFR, manufactured by Kolon) at 110 ° C. and 4 kgf / cm 2 conditions at a rate of 2 m / min, the PET film began to be released. The force per unit area required to release from 5 cm to 8 cm from the starting point was measured using UTM (4303 series, Instron).

The conditions for laminating the PET film are the same as the conditions for bonding with a mask during general exposure, and the measured adhesive force is the adhesive force between the resin protective layer and the PET film in Examples and Comparative Examples 2 and 1. It is adhesive force between the photosensitive resin layer and PET film.

(3) Change rate of adhesion of resin protective layer

For the film transfer material according to Examples 1 to 4, the first adhesive force and the second adhesive force were obtained by the following method, and the adhesive force change rate was calculated using Equation 1 below.

Equation 1

The protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm was removed, and the base film was removed after laminating the copper-clad laminate at 110 ° C. and 4 kgf / cm 2 at a speed of 2 m / min. Immediately after removing the base film, the PET film (FDFR, manufactured by Kolon) having a width of 4 cm, a length of 25 cm, and a thickness of 19 μm was laminated at a speed of 2 m / min under conditions of 110 ° C and 4 kgf / cm 2, The force per unit area required for releasing the PET film and releasing from 5 cm to 8 cm from the starting point was measured using UTM (4303 series, Instron) and defined as the first adhesive force.

In addition, the base film was peeled off in the same manner, and left for 24 hours under a temperature of 25 ° C. and a humidity of 50%. Then, a separate PET film was laminated on the resin protective layer by the method described above, and then the mold film was released. The force per unit area required for releasing from 5 cm to 8 cm was measured using UTM (4303 series, Instron) and defined as the second adhesive force.

Release force (kgf / ㎠) Adhesion (kgf / ㎠) Adhesive force change rate (%) Protective film Base film PET film (mask) Example 1 0.0039 0.0053 0.0001 Less than 10% Example 2 0.0037 0.0057 0.0005 Less than 10% Example 3 0.0038 0.0054 0.0001 Less than 10% Example 4 0.0038 0.0049 0.0001 Less than 10% Comparative Example 1 0.0031 0.0067 0.0064 Less than 10%

As a result of the measurement, it can be seen that the releasing force between the photosensitive resin layer and the protective film and the releasing force between the resin protective layer and the base film are in a range that does not impair workability. You can see low. As a result, it can be seen that the adhesive force between the resin protective layer of the embodiment and the mask material generally used under the exposure conditions is very low, and thus, the handling is easy during exposure.

Thereafter, the film-type photosensitive transfer material prepared in Examples and Comparative Examples was formed on a printed circuit board by the following method, and physical property evaluation was performed as follows.

A brush preprocessor is used for the copper clad laminate (CCL) to form new copper surfaces and to form the appropriate surface finish. After acid treatment in 5% sulfuric acid solution, washed with water, dried and added to the laminator. As a laminator, Hakuto Mach 610i was used, and the film-type photosensitive transfer material prepared in Examples and Comparative Examples was laminated on a copper clad laminate at 110 ° C. at a pressure of 4 kgf / cm 2 and a speed of 2 m / min. At this time, no preheating was performed. Then, the exposure was performed by irradiating with a UV exposure machine (Perkin Elmer OB-7120, 5KW parallel light). After the exposure, the printed circuit board was developed by passing through a developer.

In this case, in Examples 1 to 4 including the resin protective layer, the base film was peeled off before the exposure process, and in the case of Comparative Example 1 in which the resin protective layer was not included, the base film was peeled off before the developing process after exposure.

(4) sensitivity and exposure dose

In the case of exposure, after placing the sensitizer (21-stage Stouffer Step Tablet) on the resin protective layer in the case of Examples 1 to 4 and on the base film in the case of Comparative Example 1, The exposure amount was measured using a photometer (UV-351, manufactured by ORC), and the values are shown in Table 2. At this time, the sensitivity was evaluated by the maximum number of units of the photosensitive resist remaining on the substrate after development.

(5) Developing time

The development time was measured by passing the printed circuit board after the lamination on the copper-clad laminate through a developing device as the minimum development time and the time at which the laminated part was completely washed by the developer solution, and the actual development time was twice the minimum development time. Calculated as In this case, when the resin protective layer is present, the actual development time was calculated as the minimum development time plus the minimum development time plus the development time of the resin protection layer.

(6) Circuit Properties: Resolution, Fine Line Adhesion, 1/1 (Line / Space) Resolution

The Kolon Test Artwork was used to evaluate the circuit properties by measuring the resolution, thin line adhesion, and 1/1 (Line / Space) resolution.

In this experiment, the resolution is a measure of how small the line width was developed when the unexposed areas were developed. The smaller this value, the higher the resolution.The mask used for measuring the measured resolution was 0.5 to 4㎛ ~ 20㎛. The mask is formed at intervals of 탆 and a mask made of a thickness of 400 탆 is used for the resolution of the value to be realized. The thin line adhesion value is a measure of how small the line width after exposure is formed to form a straight line circuit without being eroded. The smaller the value, the better the fine line adhesion value, and the mask used for measuring the measured thin line adhesion value. Is formed at intervals of 0.5㎛ from 4㎛ ~ 20㎛ and using a mask made of a 400㎛ spacing to the thin line adhesion value of the value to be implemented. In addition, 1/1 resolution represents the value of the cleanest developed minimum line width with a distance of 1: 1 between the circuit line and the circuit line.

(7) surface analysis

After the printed circuit board to which the film-type photosensitive transfer material of Example 1 and Comparative Example 1 was applied was subjected to the exposure and development processes as described above, the surface of the printed circuit board was photographed with an electron microscope and shown in FIGS. 4 and 5, respectively.

Developing time Exposure conditions Circuit properties at least
Developing time
(sec) real
Developing time
(sec) Exposure
energy
(mJ / ㎠) Sensitivity
(sst / 21sst) resolution
(Μm) Fine wire adhesion
(Μm) 1/1 resolution
(Μm) Example 1

10

18

50 5/21 7 13 9 60 6/21 9 11 9 80 7/21 9 8 9 Example 2

11

19

50 5/21 7 13 9 60 6/21 9 11 9 80 7/21 10 9 10 Example 3

8.5

16.5

50 5/21 7 13 9 60 6/21 8 11 9 80 7/21 9 8 9 Example 4

10

18

50 5/21 7 13 9 60 6/21 9 11 9 80 7/21 9 8 9 Comparative Example 1
8

16

50 5/21 8 13 10 60 6/21 11 13 11 80 7/21 13 8 13

As a result of the measurement, the amount of exposure required to implement the same number of steps was almost no difference between the embodiment and the comparative example, the circuit property measurement results, it can be seen that the result of the embodiment, even better results, including the resolution.

On the other hand, in the case of the film-type photosensitive transfer material including the resin protective layer of the present invention, it can be seen that the developing time of the resin protective layer is about 0.5 to 3 seconds per 1 μm of the thickness of the resin protective layer.

In addition, as a result of surface observation through the electron micrographs of FIGS. 4 and 5, in the case of FIG. 4, which is a surface photograph of the printed circuit board to which the film-type photosensitive transfer material according to Example 1 is applied, the magnification is larger than that of FIG. 5 to which Comparative Example 1 is applied. Nevertheless, it can be seen that the irregularities of the side and the surface are less visible. Therefore, when the film-type photosensitive transfer material of this invention is applied, it turns out that not only handling is easy at the time of exposure, but resolution is improved.

Example 5

(a) 20 g of PVA205 (KURARAY Co., Japan) was added to 100 g of distilled water and stirred at 80 ° C. for 6 hours to completely dissolve to obtain a composition for the resin protective layer. 19 μm, KOLON) was coated using a coating bar and dried at 80 ° C. for 10 minutes using a hot air oven to form a resin protective layer having a thickness of 2 μm.

(c) A photosensitive resin composition was prepared in the composition and content used for UH-9200 series (Kolon). Specifically, the photoinitiators were dissolved in methyl ethyl ketone and methyl alcohol as solvents, and then photopolymerizable oligomers and binder polymers were added and mixed for 1 hour using a mechanical stirrer to prepare a photosensitive resin composition.

(d) coating the photosensitive resin composition on a 19 μm thick protective film (silicone release-treated polyethylene terephthalate film, CY201-19 μm, KOLON) using a coating bar and then using a hot air oven for 6 minutes at 80 ° C. It dried and the 15-micrometer-thick photosensitive resin layer was formed.

(e) film-type photosensitive transfer having a thickness of 55 μm in the form as shown in FIG. 1 by laminating at a pressure of 4 kgf / cm 2 at 50 ° C. such that the dried photosensitive resin layer of the film (d) and the resin protective layer of (b) contact each other. The material was prepared.

<Example 6>

(a) 20 g of PVA205 (KURARAY, Japan) and 0.5 g of BYK-349 (wetting agent, BYK Chemie) were added to 100 g of distilled water and stirred at 80 ° C. for 6 hours to completely dissolve to obtain a composition for a resin protective layer. A film was coated on a film (polyethylene terephthalate film, trade name FDFR-19, KOLON) using a coating bar, and dried at 80 ° C. for 10 minutes using a hot air oven to form a resin protective layer having a thickness of 2 μm.

(c) A photosensitive resin composition was prepared in the composition and content used for UH-9200 series (Kolon). Specifically, the photoinitiators were dissolved in methyl ethyl ketone and methyl alcohol as solvents, and then photopolymerizable oligomers and binder polymers were added and mixed for 1 hour using a mechanical stirrer to prepare a photosensitive resin composition.

(d) coating the photosensitive resin composition on a 19 μm thick protective film (silicone release-treated polyethylene terephthalate film, CY201-19 μm, KOLON) using a coating bar and then using a hot air oven for 6 minutes at 80 ° C. It dried and the 15-micrometer-thick photosensitive resin layer was formed.

(e) film-type photosensitive film having a thickness of 55 μm in the form as shown in FIG. 1 by laminating at a pressure of 4 kgf / cm 2 at 50 ° C. such that the dried photosensitive resin layer of the film of (d) and the resin protective layer of (b) are in contact with each other. A transfer material was prepared.

<Example 7>

(a) 20 g of PVA205 (KURARAY Co., Japan) was added to 100 g of distilled water and stirred at 80 ° C. for 6 hours to completely dissolve to obtain a composition for the resin protective layer. 19 μm, KOLON) was coated using a coating bar and dried at 80 ° C. for 10 minutes using a hot air oven to form a resin protective layer having a thickness of 10 μm.

(c) A photosensitive resin composition was prepared in the composition and content used for UH-9200 series (Kolon). Specifically, the photoinitiators were dissolved in methyl ethyl ketone and methyl alcohol as solvents, and then photopolymerizable oligomers and binder polymers were added and mixed for 1 hour using a mechanical stirrer to prepare a photosensitive resin composition.

(d) coating the photosensitive resin composition on a 19 μm thick protective film (silicone release-treated polyethylene terephthalate film, CY201-19 μm, KOLON) using a coating bar and then using a hot air oven for 6 minutes at 80 ° C. It dried and the 15-micrometer-thick photosensitive resin layer was formed.

(e) film-type photosensitive transfer having a thickness of 63 μm in the form as shown in FIG. The material was prepared.

The release force, the adhesive force of the resin protective layer, the MEK solubility, and the adhesive force change rate of the film-type photosensitive transfer material prepared in Examples 5 to 7 were measured as follows, and the results are shown in Table 3 below.

(1) release force

<Protective Film>

Using the universal testing machine (UTM, 4303 series, Instron Co., Ltd.), the force per unit area required to release the protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm from 5 cm to 8 cm from the starting point. It was measured by.

<Base film>

After removing the protective film of the film-type photosensitive transfer material specimen of 3cm in width, 20cm in length, it was laminated on the copper clad laminate at 110 ° C. at a speed of 2 m / min and a pressure of 4 kgf / cm 2. Then, the force per unit area required for releasing the base film from 5 cm to 8 cm from the starting point while releasing the base film was measured using UTM (4303 series, Instron).

(2) adhesion

The protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm was removed, and the base film was removed after laminating the copper-clad laminate at 110 ° C. and 4 kgf / cm 2 at a speed of 2 m / min. After laminating a 4 cm wide, 25 cm long, 19 μm thick PET film (FDFR, manufactured by Kolon) at 110 ° C. and 4 kgf / cm 2 conditions at a rate of 2 m / min, the PET film began to be released. The force per unit area required to release from 5 cm to 8 cm from the starting point was measured using UTM (4303 series, Instron).

The conditions for laminating the PET film are the same as the conditions for bonding with the mask during normal exposure, and the measured adhesive force is the adhesive force between the resin protective layer and the PET film.

(3) Change rate of adhesion of resin protective layer

For the film transfer material according to Examples 5 to 7, the first adhesive force and the second adhesive force were obtained by the following method, and the adhesive force change rate was calculated using the following equation (1).

Equation 1

The protective film of the film-type photosensitive transfer material specimen having a width of 3 cm and a length of 20 cm was removed, and the base film was removed after laminating the copper-clad laminate at 110 ° C. and 4 kgf / cm 2 at a speed of 2 m / min. Immediately after removing the base film, the PET film (FDFR, manufactured by Kolon) having a width of 4 cm, a length of 25 cm, and a thickness of 19 μm was laminated at a speed of 2 m / min under conditions of 110 ° C and 4 kgf / cm 2, The force per unit area required for releasing the PET film and releasing from 5 cm to 8 cm from the starting point was measured using UTM (4303 series, Instron) and defined as the first adhesive force.

In addition, the base film was peeled off in the same manner, and left for 24 hours under a temperature of 25 ° C. and a humidity of 50%. Then, a separate PET film was laminated on the resin protective layer by the above-described method, and then the mold film was released. The force per unit area required for releasing from 5 cm to 8 cm was measured using UTM (4303 series, Instron) and defined as the second adhesive force.

(4) Solubility in methyl ethyl ketone of the resin protective layer

The solubility of the resin protective layer in methyl ethyl ketone was 50 g of the resin protective layer in 100 g of methyl ethyl ketone, stirred at 25 ° C. for 1 hour, filtered through a filter paper, and the weight of the resin protective layer remaining on the filter paper was measured. Solubility is defined as the amount of reduction in the weight of the resin protective layer.

Release force (kgf / ㎠) Adhesion (kgf / ㎠) Adhesive force change rate (%) Solubility in MEK of the resin protective layer (g) Protective film Base film PET film (mask) Example 5 0.0048 0.0050 0.0001 10 0.1 Example 6 0.0048 0.0057 0.0001 10 0.1 Example 7 0.0048 0.0050 0.0001 10 0.1

As a result of the measurement, it can be seen that the release force between the photosensitive resin layer and the protective film and the release force between the resin protective layer and the base film are in a range that does not impair workability, and the resin protective layer has low adhesive force with the PET for mask. Able to know. As a result, it can be seen that the adhesive force between the resin protective layer of the embodiment and the mask material generally used under the exposure conditions is very low, and thus, the handling is easy during exposure.

In addition, the resin protective layer has a low solubility of MEK of less than 5 g. Thus, polyvinyl alcohol is prevented from diffusing components between the photosensitive resin layer and the resin protective layer in the storage and distribution of the film-type photosensitive resin for a long time. It turns out that a system resin layer is optimal as a resin protective layer.

In addition, the resin protective layer has a low adhesive force change rate of 5000% or less, thereby preventing problems such as adhesion with a mask due to moisture absorption even if a certain time is required after removing the base film in a post-process using a film-type photosensitive transfer material. It can be seen that.

Thereafter, the film-type photosensitive transfer material prepared in Examples and Comparative Examples was formed on the printed circuit board by the following method, and the physical properties were evaluated as follows, and the results are shown in Table 4 below.

A brush preprocessor is used for the copper clad laminate (CCL) to form new copper surfaces and to form the appropriate surface finish. After acid treatment in 5% sulfuric acid solution, washed with water, dried and added to the laminator. As a laminator, Hakuto Mach 610i was used, and the film-type photosensitive transfer material prepared in Examples and Comparative Examples was laminated on a copper clad laminate at 110 ° C. at a pressure of 4 kgf / cm 2 and a speed of 2 m / min. At this time, no preheating was performed. Then, the exposure was performed by irradiating with a UV exposure machine (Perkin Elmer OB-7120, 5KW parallel light). After the exposure, the printed circuit board was developed by passing through a developer.

At this time, the base film was peeled off before the exposure step.

(5) sensitivity and exposure dose

After exposing the sensitizer (21-stage Stouffer Step Tablet) on the protective layer at the time of exposure, the exposure amount for obtaining the 5-stage, 6-stage, and 7-stage sensitivity was measured using a photometer (UV-351, manufactured by ORC). And the values are shown in Table 1. At this time, the sensitivity was evaluated by the maximum number of units of the photosensitive resist remaining on the substrate after development.

(6) Developing time

The development time was measured by passing the printed circuit board after the lamination on the copper-clad laminate through a developing device as the minimum development time and the time at which the laminated part was completely washed by the developer solution, and the actual development time was twice the minimum development time. Calculated as In this case, the actual development time was calculated by adding the minimum development time to the minimum development time.

(7) Circuit Properties: Resolution, Fine Line Adhesion, 1/1 (Line / Space) Resolution

The Kolon Test Artwork was used to evaluate the circuit properties by measuring the resolution, thin line adhesion, and 1/1 (Line / Space) resolution.

In this experiment, the resolution is a measure of how small the line width was developed when the unexposed areas were developed. The smaller this value, the higher the resolution.The mask used for measuring the measured resolution was 0.5 to 4㎛ ~ 20㎛. The mask is formed at intervals of 탆 and a mask made of a thickness of 400 탆 is used for the resolution of the value to be realized. The thin line adhesion value is a measure of how small the line width after exposure is formed to form a straight line circuit without being eroded. The smaller the value, the better the fine line adhesion value, and the mask used for measuring the measured thin line adhesion value. Is formed at intervals of 0.5㎛ from 4㎛ ~ 20㎛ and using a mask made of a 400㎛ spacing to the thin line adhesion value of the value to be implemented. In addition, 1/1 resolution represents the value of the cleanest developed minimum line width with a distance of 1: 1 between the circuit line and the circuit line.

(6) surface analysis

The printed circuit boards to which the film-type photosensitive transfer materials of Examples 5 to 7 were subjected to the exposure and development processes as described above, and the surfaces thereof were photographed by electron microscopy, and are shown in FIGS. 6 to 8, respectively.

Developing time Exposure conditions Circuit properties at least
Developing time
(sec) real
Developing time
(sec) Exposure
energy
(mJ / ㎠) Sensitivity
(sst / 21sst) resolution
(Μm) Fine wire adhesion
(Μm) 1/1 resolution
(Μm) Example 5
9 17 50 5/21 7 13 9 60 6/21 9 11 9 80 7/21 9 8 9 Example 6
9 17 50 5/21 7 13 9 60 6/21 9 11 9 80 7/21 9 8 9 Example 7
13 21 50 5/21 8 13 9 60 6/21 9 11 9 80 7/21 10 8 10

As a result of the measurement, the amount of exposure required to implement the same number of steps was almost no difference between the embodiment and the comparative example, the circuit property measurement results, it can be seen that the result of the embodiment, even better results, including the resolution.

On the other hand, in the case of the film-type photosensitive transfer material including the resin protective layer of the present invention, it can be seen that the developing time per 1 μm of the thickness of the resin protective layer is about 0.5 to 3 seconds.

In addition, as a result of surface observation through the electron micrographs of FIGS. 6 to 8, Comparative Example 1 of FIG. 6 to FIG. Although the magnification is larger than that of FIG. Therefore, when the film-type photosensitive transfer material of this invention is applied, it turns out that not only handling is easy at the time of exposure, but resolution is improved.

1 is a cross-sectional view of a laminated structure of a film-type photosensitive transfer material of a preferred form according to the present invention,

2 is a cross-sectional view during exposure of a substrate for a display element to which a film-type photosensitive transfer material of the present invention is applied;

3 is a cross-sectional view during exposure of a substrate for a display device to which a film type photosensitive transfer material of a general three-layer laminated structure is applied;

4 is an electron micrograph taken at 800 times magnification of the surface of a printed circuit board after the development process manufactured in the embodiment of the present invention;

5 is an electron micrograph taken at 600 times magnification of the surface of a printed circuit board after the developing process manufactured in Comparative Example.

6 to 8 is an electron micrograph (1500 times, 2000 times, 2500 times, respectively) photographed by enlarging the surface of the printed circuit board after the developing process prepared in Examples 5 to 7 of the present invention.

* Detailed description of the main symbols in the drawing

10: cover film

20: photosensitive resin layer

30: resin protective layer

40: base film

50: copper clad laminate (FCCL)

60 mask

Claims (12)

A base film, a resin protective layer, a photosensitive resin layer, and a protective film; The resin protective layer is defined as the force per unit area required to peel off the base film, laminate a separate PET film on the resin protective layer, and then begin to release it to release from 5 cm to 8 cm from the starting point. Adhesive strength is 0.005kgf / cm 2 or less, The resin protective layer is an alkali developable polymer layer, and is formed from a coating liquid containing a water-soluble polymer having a weight average molecular weight of 5,000 to 300,000, The resin protective layer is a film-type photosensitive transfer material, characterized in that the solubility in the methyl ethyl ketone solution at 25 ℃ defined as follows 5g or less. Solubility: Add 50 g of resin protective layer to 100 g of methyl ethyl ketone, stir at 25 ° C. for 1 hour, filter with filter paper, and measure the weight of the resin protective layer remaining on the filter paper. delete delete delete The photosensitive transfer material according to claim 1, wherein the release force between the protective film and the photosensitive resin layer is smaller than the release force between the base film and the resin protective layer. The film type photosensitive transfer material according to claim 1, wherein the resin protective layer has a thickness of 0.001 to 10 µm. The film-type photosensitive transfer material according to claim 1, wherein the resin protective layer has a change in adhesion force of 5000% or less represented by the following formula (1). Equation 1

In the above formula, the first adhesive force is the force per unit area required to release a separate PET film on the resin protective layer immediately after peeling off the base film, and then start to release the mold from 5 cm to 8 cm from the starting point. Defined, the second adhesive force is peeled off the base film and left for 240 hours at a temperature of 25C, 50% humidity conditions, then laminating a separate PET film on the resin protective layer and starting to release it, starting from 5 cm from the starting point 8 It is defined as the force per unit area required to release to the point cm. The film type photosensitive transfer material according to claim 1 or 7, wherein the resin protective layer is a polyvinyl alcohol-based resin layer. The film type photosensitive transfer material according to claim 8, wherein the resin protective layer comprises at least one additive selected from a wetting agent, a leveling agent, an antifoaming agent, an adhesive, and an adhesive. The film-type photosensitive transfer material according to claim 1, wherein the protective film is a polyester film with or without a release layer. The film-type photosensitive transfer material according to claim 1 or 10, wherein the base film is a polyester film with or without a release layer. The display element substrate which formed the pattern using the film type photosensitive transfer material of Claim 1.

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