JP2023508163A - Photosensitive laminate, method for producing photosensitive laminate, and method for producing circuit board - Google Patents

Abstract

The present invention comprises a supporting substrate; and a photosensitive resin layer formed on the supporting substrate, wherein the photosensitive resin layer has 5 cells/mm ² or less of bubbles having a diameter of less than 1 μm. The present invention relates to a laminate and a method for producing the photosensitive laminate.

Description

The present invention relates to a photosensitive laminate, a method for producing a photosensitive laminate, and a method for producing a circuit board.

The photosensitive resin composition is used in printed circuit boards (PCB) and lead frames such as dry film photoresist (DFR) and liquid photoresist (Liquid Photoresist Ink). used in the form of
Recently, with the trend toward lighter, thinner, shorter and smaller semiconductor devices and multi-stage packaging, there is a demand for high-density circuit boards. A circuit board manufacturing process using a photosensitive laminate including a photosensitive resin layer is also widely used.
Accordingly, there is a continuing demand for the development of methods and processes that achieve higher density and sensitivity while ensuring higher reliability and enable the formation of finer wiring.

Japanese Patent Publication No. 2006-106287 (publication date: 2006.04.20.)

The present invention provides a photosensitive laminate capable of reducing defects in the formation of fine wiring, ensuring high reliability during development, and enabling high-density circuit formation.
Moreover, this invention provides the manufacturing method of the said photosensitive laminated body.
Furthermore, the present invention provides a method of manufacturing a circuit board using the photosensitive laminate.

The present specification includes a supporting substrate; and a photosensitive resin layer formed on the supporting substrate, and the photosensitive resin layer has 5 or less cells/ ^mm2 having a diameter of less than 1 μm. A photosensitive laminate is provided.
Further, the present specification provides a method for manufacturing a circuit board using the photosensitive laminate.
Furthermore, the present specification provides a method for manufacturing the photosensitive laminate.
Hereinafter, a photosensitive laminate, a method for producing the photosensitive laminate, and a method for producing a circuit board according to specific embodiments of the invention will be described in more detail.
As used herein, the weight average molecular weight means the polystyrene-equivalent weight average molecular weight measured by the GPC method. In the process of measuring the polystyrene-equivalent weight-average molecular weight measured by the GPC method, a commonly known analyzer and a detector such as a Refractive Index Detector and an analytical column can be used. Any temperature conditions, solvents, flow rates can be applied.
As a specific example of the measurement conditions, the alkali-developable binder resin is dissolved in tetrahydrofuran so as to have a concentration of 1.0 (w/w)% in THF (about 0.5 (w/w)% based on the solid content). After filtration using a syringe filter of 0.45 μm Pore Size, 20 μl was injected into GPC, and tetrahydrofuran (THF) was used as the mobile phase for GPC, flowing at a flow rate of 1.0 mL / min, The columns were one Agilent PLgel 5 μm Guard (7.5×50 mm) and two Agilent PLgel 5 μm Mixed D (7.5×300 mm) connected in series, and an Agilent 1260 Infinity II System, RI Detector was used as a detector. was measured at 40°C using
Polystyrene standard samples (STD A, B, C, D) in which polystyrene having the following various molecular weights were dissolved in tetrahydrofuran at a concentration of 0.1 (w / w)% were measured with a 0.45 μm Pore Size. After filtering with Syringe Filter, the value of the weight average molecular weight (Mw) of the alkali-developable binder resin was determined using a calibration curve formed by injecting into GPC.
STD A (Mp): 791,000/27, 810/945
STD B (Mp): 282,000/10,700/580
STD C (Mp): 126,000/4,430/370
STD D (Mp): 51,200/1,920/162
In the present specification, the term "(photo)cured product" or "(photo)cured" means that all constituents having unsaturated groups that can be cured or crosslinked in the chemical structure are cured, crosslinked or polymerized. Not only that, it can also include cases where a part thereof is cured, crosslinked or polymerized.
According to one embodiment of the invention, a supporting substrate; Provided is a photosensitive laminate in which 5 cells/mm ² or less of cells having a diameter of less than 1 μm are present in the photosensitive resin layer.
The present inventors have newly developed a photosensitive laminate containing a photosensitive resin layer in which 5 bubbles/mm ² or less having a diameter of less than 1 μm are present. It is possible to achieve high sensitivity to exposure during the substrate manufacturing process, which increases reliability during development. While maintaining high reliability, it also achieves high density and sensitivity, enabling the formation of finer wiring. Through experiments, the inventors have completed the invention.
The present inventors continue research and development to remove microbubbles or traces of microscopic by-products that can be generated for various reasons in the manufacturing process, and will be detailed in the method for manufacturing a photosensitive laminate described later. A resin composition containing a mixed solvent containing a high boiling point solvent having a boiling point of 115° C. or higher and a low boiling point solvent having a boiling point of 100° C. or lower together with an alkali developable binder resin, a photopolymerizable compound and a photoinitiator. By forming a photosensitive resin layer using , bubbles having a diameter of less than 1 μm were present in the photosensitive resin layer at 5/mm ² or less, or 3/mm ² or less.
Further, in the method for producing a photosensitive laminate, in addition to using a mixed solvent containing a high boiling point solvent having a boiling point of 115 ° C. or higher and a low boiling point solvent having a boiling point of 100 ° C. or lower, drying speed and / or By adjusting the drying temperature, the amount of microbubbles formed in the photosensitive resin layer can be greatly reduced or substantially eliminated.
Meanwhile, bubbles having a diameter of less than 1 μm may exist in the photosensitive resin layer at 5/mm ² or less, or 3/mm ² or less. There may be a slight amount of air bubbles having a diameter of less than 1 μm or substantially no air bubbles on the opposite side of the interface between or on the outer side of the photosensitive resin layer.
More specifically, three cells having a diameter of less than 1 μm are present within 50% of the total thickness of the photosensitive resin layer from the opposite side of the interface between the supporting substrate and the photosensitive resin layer. /mm ² or less.
Due to the existence of a small amount of air bubbles having a diameter of less than 1 μm or the absence of substantial air bubbles on the surface opposite to the interface between the support substrate and the photosensitive resin layer or on the outer surface side of the photosensitive resin layer. , during development, the reliability is increased, high-density circuit formation is possible, and defects in the formation of fine wiring can be reduced, so that when the photosensitive laminate is used, high sensitivity to exposure is achieved. can be realized, and the manufacturing yield of high-density printed circuit boards can be improved.

In addition, the photosensitive laminate contains a very small amount of bubbles having a diameter of less than 1 μm, or substantially does not contain bubbles having a diameter of less than 1 μm, and does not contain bubbles having a diameter of 1 μm or more and 5 μm or less.
Thus, when manufacturing a circuit board using the photosensitive laminate in which a small amount of air bubbles having a diameter of less than 1 μm are present in the photosensitive resin layer, high density and sensitivity can be achieved while ensuring high reliability. can be realized, and finer wiring can be formed.
More specifically, even when the photosensitive resin layer is exposed to ultraviolet light and developed with an alkaline solution, defects may not occur over the entire area, or may occur in very small amounts. There is substantially no defect on the upper surface of the photosensitive resin layer, and there may be a very small amount of defects on the lower surface and inside of the photosensitive resin layer after development. be.
Specifically, after the photosensitive resin layer is exposed to ultraviolet light and developed with an alkaline solution, there are 3 defects/mm having a cross-sectional diameter of 0.3 μm to 4 μm, or 0.5 μm to 3 μm. ² or less, or 1/mm ² or less, and may be substantially absent. The cross-sectional diameter of the defect may be defined as the largest diameter among the diameters of the defect defined by a cross section in one direction on the photosensitive resin layer.
The exposure and development conditions are not particularly limited. For example, the exposure is performed at an energy that causes the remaining number of steps to be 15 as measured using a 41-step tablet manufactured by Stouffer Graphic Arts Equipment in a wavelength range of 340 nm to 420 nm. 1 minute to 60 minutes. Also, the development can be carried out by a method such as a spraying method using an alkaline aqueous solution such as Na ₂ CO ₃ having a concentration of 0.1 to 3.0 wt %.
Also, with the photosensitive laminate, higher density and sensitivity can be achieved while using lower energy. More specifically, the energy at which the number of remaining steps is 15 when measured using a 41-step tablet manufactured by Stouffer Graphic Arts Equipment in the wavelength range of 340 nm to 420 nm of the light irradiated to the photosensitive laminate. The amount may be 300 mJ/cm ² or less, or 100 mJ/cm ² or less, and a resolution of 15 μm or less, or 10 μm or less can be achieved after development.
In the photosensitive laminate, the thicknesses of the supporting substrate and the photosensitive resin layer are not greatly limited. Preferably, the thickness of the photosensitive resin layer may be between 1 μm and 100 μm, or between 5 μm and 50 μm.
On the other hand, the characteristics of the photosensitive laminate and the structural characteristics of the presence of 5 cells/mm ² or less of bubbles having a diameter of less than 1 μm in the photosensitive resin layer are due to the manufacturing method described above. Alternatively, it may be due to the characteristics of the photosensitive resin layer.

前記化学式４において、Ｒ_３は、水素、または炭素数１～１０のアルキルであり、

前記化学式５において、Ｒ_４は、水素、または炭素数１～１０のアルキルであり、Ｒ_５は、炭素数１～１０のアルキルであり、

前記化学式６において、Ａｒは、炭素数６～２０のアリールである。
前記化学式４～６において、Ｒ_３およびＲ_４は、互いに同一または異なり、それぞれ独立して、水素、または炭素数１～１０のアルキルであり、Ｒ_５は、炭素数１～１０のアルキルであり、Ａｒは、炭素数６～２０のアリールである。 Specifically, the photosensitive resin layer may contain an alkali-developable binder resin. The alkali-developable binder contains at least one carboxyl group in the molecule and can react with an alkali during the development process.
Specific examples of the alkali-developable binder are not limited, but a repeating unit represented by the following chemical formula 4, a repeating unit represented by the following chemical formula 5, and a repeating unit represented by the following chemical formula 6 It may be a polymer or a copolymer containing one or more repeating units selected from the group consisting of.

In Formula 4, R ₃ is hydrogen or alkyl having 1 to 10 carbon atoms,

In Formula 5, R ₄ is hydrogen or alkyl having 1 to 10 carbon atoms, R ₅ is alkyl having 1 to 10 carbon atoms,

In Formula 6, Ar is an aryl having 6 to 20 carbon atoms.
In Formulas 4 to 6, R ₃ and R ₄ are the same or different from each other and each independently represent hydrogen or alkyl having 1 to 10 carbon atoms, and R ₅ represents alkyl having 1 to 10 carbon atoms. , Ar are aryl having 6 to 20 carbon atoms.

前記化学式４－１において、Ｒ_３は、水素、または炭素数１～１０のアルキルである。前記化学式４－１において、Ｒ_３に関する内容は、前記化学式４で上述した内容と同じである。前記化学式４－１で表される単量体の具体例として、アクリル酸（Ａｃｒｙｌｉｃ ａｃｉｄ、ＡＡ）、メタクリル酸（Ｍｅｔｈａｃｒｙｌｉｃ ａｃｉｄ、ＭＡＡ）が挙げられる。
前記化学式５で表される繰り返し単位は、下記の化学式５－１で表される単量体に由来する繰り返し単位であってもよい。

前記化学式５－１において、Ｒ_４は、水素、または炭素数１～１０のアルキルであり、Ｒ_５は、炭素数１～１０のアルキルである。前記化学式３－１において、Ｒ_４およびＲ_５に関する内容は、前記化学式３で上述した内容と同じである。前記化学式３－１で表される単量体の具体例として、メチルメタクリレート（Ｍｅｔｈｙｌｍｅｔｈａｃｒｙｌａｔｅ、ＭＭＡ）、ブチルアクリレート（Ｂｕｔｙｌ ａｃｒｙｌａｔｅ、ＢＡ）が挙げられる。
前記化学式６で表される繰り返し単位は、下記の化学式６－１で表される単量体に由来する繰り返し単位であってもよい。

前記化学式６－１において、Ａｒは、炭素数６～２０のアリールである。前記化学式６－１において、Ａｒに関する内容は、前記化学式４で上述した内容と同じである。前記化学式６－１で表される単量体の具体例として、スチレン（Ｓｔｙｒｅｎｅ、ＳＭ）が挙げられる。 R ₅ is an alkyl having 1 to 10 carbon atoms, and specific examples of the alkyl having 1 to 10 carbon atoms include methyl. Ar is an aryl having 6 to 20 carbon atoms, and specific examples of the aryl having 6 to 20 carbon atoms include phenyl.
The repeating unit represented by Chemical Formula 4 may be a repeating unit derived from a monomer represented by Chemical Formula 4-1 below.

In Formula 4-1, R ₃ is hydrogen or alkyl having 1 to 10 carbon atoms. In Chemical Formula 4-1, the contents of R ₃ are the same as those described in Chemical Formula 4 above. Specific examples of the monomer represented by Chemical Formula 4-1 include acrylic acid (AA) and methacrylic acid (MAA).
The repeating unit represented by Chemical Formula 5 may be a repeating unit derived from a monomer represented by Chemical Formula 5-1 below.

In Formula 5-1, R ₄ is hydrogen or alkyl having 1 to 10 carbon atoms, and R ₅ is alkyl having 1 to 10 carbon atoms. In Chemical Formula 3-1, the contents of R ₄ and R ₅ are the same as those described in Chemical Formula 3 above. Specific examples of the monomer represented by Formula 3-1 include methyl methacrylate (MMA) and butyl acrylate (BA).
The repeating unit represented by Chemical Formula 6 may be a repeating unit derived from a monomer represented by Chemical Formula 6-1 below.

In Formula 6-1, Ar is an aryl having 6 to 20 carbon atoms. In Chemical Formula 6-1, the contents of Ar are the same as those described in Chemical Formula 4 above. A specific example of the monomer represented by Formula 6-1 is styrene (SM).

On the other hand, the alkali-developable binder resin can serve as a base material for the photosensitive resin layer, and thus must have a minimum molecular weight, for example, 20,000 g/mol to 300 g/mol. 000 g/mol, or from 30,000 g/mol to 150,000 g/mol.
In addition, the alkali-developable binder resin should have a certain level of heat resistance or higher, so that it can have a glass transition temperature of 20° C. or higher and 150° C. or lower.
Further, the alkali-developable binder resin may have an acid value of 100 mgKOH/g to 300 mgKOH/g in consideration of the developability of the photosensitive resin layer.
Meanwhile, the alkali-developable binder resin may contain two or more alkali-developable binders having different types or different properties. Specifically, the alkali-developable binder resin may include a first alkali-developable binder resin and a second alkali-developable binder resin.
The first alkali-developable binder resin and the second alkali-developable binder resin may have a weight average molecular weight of 30000 g/mol or more and 150000 g/mol or less and a glass transition temperature of 20° C. or more and 150° C. or less, respectively. They can have different weight average molecular weights, glass transition temperatures, or acid numbers.
For example, the first alkali-developable binder resin may have an acid value of 140 mgKOH/g or more and 160 mgKOH/g or less. Further, the second alkali-developable binder resin may have an acid value of 160 mgKOH/g or more and 200 mgKOH/g or less.

Further, the glass transition temperature ratio between the first alkali-developable binder resin and the second alkali-developable binder resin is 1:1.5 or more and 1:5 or less, 1:1.5 or more and 1:3 or less, 1:1. 5 or more and 1:2 or less, 1:1.5 or more and 1:1.8 or less, 1:1.5 or more and 1:75 or less, or 1:1.6 or more and 1:7 or less.
Further, the acid value ratio of the first alkali-developable binder resin and the second alkali-developable binder resin is 1:1.01 or more and 1:1.5 or less, 1:1.1 or more and 1:1.5 or less, or 1 : 1.25 or more and 1:1.5 or less, or 1:1.4 or more and 1:1.5 or less.
Meanwhile, the photosensitive resin layer may comprise a cross-linked copolymer between an alkali-developable binder resin and a photopolymerizable compound containing (meth)acrylate monomers or oligomers.
The photopolymerizable compound containing the (meth)acrylate monomer or oligomer serves as a cross-linking agent that enhances the mechanical strength of the photosensitive resin layer, enhances resistance to developer, and imparts flexibility to the cured film. can play a role.
The content of the photopolymerizable compound containing the (meth)acrylate monomer or oligomer can be adjusted according to the specific use and characteristics of the photosensitive resin layer. 1 to 80 parts by weight of a photopolymerizable compound containing a (meth)acrylate monomer or oligomer can be included.
The photopolymerizable compound may be a monofunctional or polyfunctional (meth)acrylate monomer or oligomer. The photopolymerizable compound may be a commonly known monofunctional or polyfunctional (meth)acrylate monomer or oligomer. The functional compound can include a trifunctional or higher polyfunctional (meth)acrylate compound.
That is, the photosensitive laminate of the embodiment uses a mixture of two or more solvents having different boiling points as described in the manufacturing method described later, and the photopolymerizable compound used is selected to obtain a photosensitive layer. A minute amount of microbubbles may be present inside the resin layer, or they may be substantially absent.
Specifically, the trifunctional or higher polyfunctional (meth)acrylate compound has 3 or more alkylene oxide groups having 1 to 10 carbon atoms and 3 or more (meth)acrylate functional groups in the central group having 1 to 20 carbon atoms. It can have a bonded structure.

前記化学式１において、Ｒ_４は水素、または炭素数１～１０のアルキルであり、Ｒ_５は炭素数１～１０のアルキレンであり、Ｒ_６は炭素数１～２０の中心グループを含むｐが官能基であり、ｎ２は１～２０の整数であり、ｐは前記Ｒ_６に置換される官能基数であり、３～１０の整数である。
前記化学式１の化合物のより具体例としては、下記の化学式１－１の化合物が挙げられる。

前記化学式１－１において、
Ｒ_６’は炭素数１～１０の３価の官能基であり、
Ｒ_７～Ｒ_９はそれぞれ独立して、炭素数１～１０のアルキレンであり、
Ｒ_１０～Ｒ_１２はそれぞれ独立して、水素、または炭素数１～１０のアルキルであり、
ｎ３～ｎ５はそれぞれ独立して、１～３の整数である。
一方、前記光重合性化合物は、単官能（メタ）アクリレート化合物または二官能（メタ）アクリレート化合物をさらに含むことができる。
前記単官能（メタ）アクリレート化合物は、炭素数１～１０のアルキレンオキシド基を含む（メタ）アクリレートを含むことができる。 Due to the structure of such a tri- or higher polyfunctional (meth)acrylate compound, a minute amount of air bubbles having a diameter of 1 μm or less may exist in the photosensitive resin layer, resulting in defects in the formation of fine wiring. can be reduced, high reliability can be ensured during development, and a high-density circuit can be formed.
More specifically, the trifunctional or higher polyfunctional (meth)acrylate compound may include a compound represented by Formula 1 below.

In Formula 1, R ₄ is hydrogen or C 1-10 alkyl, R ₅ is C 1-10 alkylene, R ₆ is a C 1-20 central group containing p functionalized n2 is an integer of 1 to 20; p is the number of functional groups substituted by R ₆ and is an integer of 3 to 10;
More specific examples of the compound of Chemical Formula 1 include compounds of Chemical Formula 1-1 below.

In the chemical formula 1-1,
R ₆ ' is a trivalent functional group having 1 to 10 carbon atoms,
R ₇ to R ₉ are each independently an alkylene having 1 to 10 carbon atoms,
R ₁₀ to R ₁₂ are each independently hydrogen or alkyl having 1 to 10 carbon atoms,
n3 to n5 are each independently an integer of 1 to 3;
Meanwhile, the photopolymerizable compound may further include a monofunctional (meth)acrylate compound or a bifunctional (meth)acrylate compound.
The monofunctional (meth)acrylate compound may contain a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms.

前記化学式２において、Ｒ_１は水素、または炭素数１～１０のアルキルであり、Ｒ_２は炭素数１～１０のアルキレンであり、Ｒ_３は炭素数１～１０のアルキルであり、ｎ１は１～２０の整数である。
前記光重合性化合物は、上述した単官能（メタ）アクリレート化合物および３官能以上の多官能（メタ）アクリレート化合物を共に含むことができる。具体的には、前記光重合性化合物は、前記炭素数１～１０のアルキレンオキシド基を含む（メタ）アクリレートを含む単官能（メタ）アクリレート化合物；および炭素数１～２０の中心グループに炭素数１～１０のアルキレンオキシド基および（メタ）アクリレート官能基がそれぞれ３個以上結合した構造を有する３官能以上の多官能（メタ）アクリレート化合物；を含むことができる。
前記感光性樹脂層および感光性積層体の特性などを考慮して、前記光重合性化合物に含まれる単官能（メタ）アクリレート化合物および３官能以上の多官能（メタ）アクリレート化合物の含有量を調節することができる。
例えば、前記光重合性化合物は、前記単官能（メタ）アクリレート化合物１００重量部に対して前記３官能以上の多官能（メタ）アクリレート化合物を１１０重量部以上５００重量部以下で含むことができる。
また、前記光重合性化合物は、前記３官能以上の多官能（メタ）アクリレート化合物１００重量部に対して前記二官能（メタ）アクリレート化合物５００重量部以上１０００重量部以下で含むことができる。 Specifically, the monofunctional (meth)acrylate compound may include a monofunctional (meth)acrylate compound represented by Formula 2 below.

In Formula 2, R ₁ is hydrogen or alkyl having 1 to 10 carbon atoms, R ₂ is alkylene having 1 to 10 carbon atoms, R ₃ is alkyl having 1 to 10 carbon atoms, and n1 is 1. ˜20 integers.
The photopolymerizable compound may include both the above-described monofunctional (meth)acrylate compound and tri- or higher polyfunctional (meth)acrylate compound. Specifically, the photopolymerizable compound includes a monofunctional (meth)acrylate compound containing a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms; and a central group having 1 to 20 carbon atoms. trifunctional or higher polyfunctional (meth)acrylate compounds having a structure in which 1 to 10 alkylene oxide groups and 3 or more (meth)acrylate functional groups are combined;
Considering the characteristics of the photosensitive resin layer and the photosensitive laminate, the contents of the monofunctional (meth)acrylate compound and the trifunctional or higher polyfunctional (meth)acrylate compound contained in the photopolymerizable compound are adjusted. can do.
For example, the photopolymerizable compound may contain 110 parts by weight or more and 500 parts by weight or less of the polyfunctional (meth)acrylate compound having three or more functionalities with respect to 100 parts by weight of the monofunctional (meth)acrylate compound.
Also, the photopolymerizable compound may be included in an amount of 500 to 1000 parts by weight of the bifunctional (meth)acrylate compound with respect to 100 parts by weight of the tri- or higher polyfunctional (meth)acrylate compound.

Meanwhile, the photopolymerizable compound may further include a monofunctional or multifunctional (meth)acrylate compound that does not overlap with the monofunctional (meth)acrylate compound and the tri- or higher polyfunctional (meth)acrylate compound. can be done. At this time, the usable monofunctional or polyfunctional (meth)acrylate compound excludes the trifunctional or higher polyfunctional (meth)acrylate compound of Chemical Formula 1 and the monofunctional (meth)acrylate compound of Chemical Formula 2.
Examples of further usable photopolymerizable compounds include, but are not limited to, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate,プロピレングリコールジメタクリレート（ｐｒｏｐｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、ポリエチレングリコールジメタクリレート、ポリプロピレングリコールジメタクリレート（ｐｏｌｙｐｒｏｐｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、ブチレングリコールジメタクリレート（ｂｕｔｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、ネオペンチルグリコールジメタクリレート（ｎｅｏｐｅｎｔｙｌ ｇｌｙｃｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、１，６－ヘキサングリコールジメタクリレート（１，６－ｈｅｘａｎｅ ｇｌｙｃｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、トリメチロールプロパントリメタクリレート（ｔｒｉｍｅｔｈｙｏｌｐｒｏｐａｎｅ ｔｒｉｍｅｔｈａｃｒｙｌａｔｅ）、トリメチロールプロパントリアクリレート（ｔｒｉｍｅｔｈｙｏｌｐｒｏｐａｎｅ ｔｒｉａｃｒｙｌａｔｅ）、グリセリンジメタクリレート（ｇｌｙｃｅｒｉｎ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、ペンタエリスリトールジメタクリレート（ｐｅｎｔａｅｒｙｔｈｒｉｔｏｌ ｄｉｍｅｔｈａｃｒｙｌａｔｅ） , pentaerythritol trimethacrylate, dipentaerythritol pentamethacrylate, 2,2-bis(4-methacryloxydiethoxyphenyl)propane (2,2-bis(4-methacryloxydiethoxyphenyl), , 2-bis (4-methacryloxypolyethoxyphenyl) propane (2,2-bis (4-methacryloxypolyethoxyphenyl) propane), 2-hydroxy-3-methacryloyloxypropyl methacrylate (2-hydroxy-3-metha ｃｒｙｌｏｙｌｏｘｙｐｒｏｐｙｌ ｍｅｔｈａｃｒｙｌａｔｅ）、エチレングリコールジグリシジルエーテルジメタクリレート（ｅｔｈｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｇｌｙｃｉｄｙｌ ｅｔｈｅｒ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、ジエチレングリコールジグリシジルエーテルジメタクリレート（ｄｉｅｔｈｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｇｌｙｃｉｄｙｌ ｅｔｈｅｒ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、フタル酸ジグリシジルエステルジメタクリレート（ｐｈｔｈａｌｉｃ ａｃｉｄ ｄｉｇｌｙｃｉｄｙｌ ｅｓｔｅｒ ｄｉｍｅｔｈａｃｒｙｌａｔｅ）、グリセリンポリExamples include glycidyl ether polymethacrylate (glycerin polyglycidyl ether polymethacrylate) and polyfunctional (meth)acrylates containing urethane groups.
On the other hand, the supporting substrate can play the role of a support for the photosensitive laminate, and can facilitate handling of the adhesive photosensitive resin layer during exposure.

Various plastic films can be used as the base film, such as acrylic films, polyethylene terephthalate (PET) films, triacetylcellulose (TAC) films, polynorbornene (PNB) films, and cycloolefin polymer (COP) films. , and polycarbonate (PC) films.
Meanwhile, the photosensitive laminate may further include a protective film formed to face the support substrate with the photosensitive resin layer at the center. The protective film prevents damage to the resist during handling and serves as a protective lid that protects the photosensitive resin layer from foreign matter such as dust. is laminated to
The protective film serves to protect the photosensitive resin layer from the outside, and is easily removed when the dry film photoresist is applied to the post-process, and is not removed during storage and distribution. , requires suitable releasability and adhesiveness.
Various plastic films can be used as the protective film. It may contain one or more plastic films selected from the group consisting of polymer (COP) films and polycarbonate (PC) films. The thickness of the protective film is not particularly limited, but can be freely adjusted within the range of 0.01 μm to 100 μm, for example.

According to still another embodiment of the invention, a mixed solvent containing a high boiling point solvent having a boiling point of 115° C. or higher and a low boiling point solvent having a boiling point of 100° C. or lower; a photopolymerizable compound; an alkali-developable binder resin; and a photoinitiator; : There is provided a method for producing a photosensitive laminate comprising the low boiling point solvent having a boiling point of 100°C or less at a weight ratio of 1:2 to 1:18.
The photosensitive laminate described above in the embodiment is provided by the manufacturing method. As described above, the photosensitive laminate includes a supporting substrate; and a photosensitive resin layer containing a photopolymerizable compound containing a trifunctional or higher polyfunctional (meth)acrylate compound and an alkali-developable binder resin. . There may be 5 cells/mm ² or less of bubbles having a diameter of less than 1 μm in the photosensitive resin layer.
In the process of forming the photosensitive resin layer, a diameter of less than 1 μm may be formed in the photosensitive resin layer due to air bubbles generated during the process of preparing the solution of the photosensitive resin composition and the process of drying the solution of the composition. However, in the method for producing a photosensitive laminate, by using a mixed solvent containing a high boiling point solvent having a boiling point of 115 ° C. or higher and a low boiling point solvent having a boiling point of 100 ° C. or lower, the solution of the photosensitive resin composition Air bubbles can be prevented from being trapped in the resin layer by delaying the evaporation time, so that there may be no more than 5 air bubbles/mm ² with a diameter of less than 1 μm in the photosensitive resin layer. .
More specifically, bubbles having a diameter of less than 1 μm may be present in the photosensitive resin layer at 5/mm ² or less, or 3/mm ² or less.
Also, within 50% of the total thickness of the photosensitive resin layer from the opposite surface of the interface between the supporting substrate and the photosensitive resin layer, there are 3 cells/mm ² or less having a diameter of less than 1 μm. may exist.
Due to the existence of a small amount of air bubbles having a diameter of less than 1 μm or the absence of substantial air bubbles on the surface opposite to the interface between the support substrate and the photosensitive resin layer or on the outer surface side of the photosensitive resin layer. , during development, the reliability is increased, high-density circuit formation is possible, and defects in the formation of fine wiring can be reduced, so that when the photosensitive laminate is used, high sensitivity to exposure is achieved. can be realized, and the manufacturing yield of high-density printed circuit boards can be improved.

As described above, the high boiling point solvent having a boiling point of 115° C. or higher may delay the evaporation time of the liquid component of the photosensitive resin composition to prevent air bubbles from being trapped in the resin layer. . Accordingly, there may be 5 or less cells/mm ² having a diameter of less than 1 μm in the photosensitive resin layer.
The mixed solvent may contain a certain amount or more of the high boiling point solvent having a boiling point of 115° C. or higher. may be 3 parts by weight or more, or 5 parts by weight or more, or 3 to 50 parts by weight, or 5 to 40 parts by weight.
By using both the high boiling point solvent having a boiling point of 115° C. or higher and the low boiling point solvent having a boiling point of 100° C. or lower, the dissolving power of the photosensitive resin composition can be increased.
The mixed solvent may contain a higher content of the low boiling point solvent having a boiling point of 100° C. or lower than the high boiling point solvent having a boiling point of 115° C. or higher.
More specifically, the mixed solvent contains the high boiling point solvent having a boiling point of 115° C. or higher and the low boiling point solvent having a boiling point of 100° C. or lower at a weight ratio of 1:2 to 1:18, or 1:3 It can be included in a weight ratio of ~1:15. The high boiling point solvent having a boiling point of 115° C. or higher: By including the low boiling point solvent having a boiling point of 100° C. or lower in the above-mentioned content, the dissolving power of the photosensitive resin composition can be increased.
Examples of high-boiling solvents having a boiling point of 115° C. or higher include butanol, dimethylformamide, N-methyl-2-pyrrolidone, gamma-butyrolactone, butyl carbitol, butyl cellosolve, methyl cellosolve, butyl acetate, diethylene glycol methyl ethyl ether, and diethylene glycol. Dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol dimethyl ether, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether propionate, dipropylene glycol dimethyl ether, cyclohexanone, propylene glycol monomethyl ether acetate (PGMEA) and one or more mixed solvents thereof.

Examples of the low boiling point solvent having a boiling point of 100° C. or less include methyl ethyl ketone, methanol, ethanol, acetone, tetrahydrofuran, ethyl acetate, isopropyl alcohol and mixed solvents of one or more thereof.
A mixed solvent containing a high boiling point solvent having a boiling point of 115° C. or higher and a low boiling point solvent having a boiling point of 100° C. or lower; an alkali developable binder resin; and a photoinitiator; The solid content may be adjusted in consideration of the application field, etc. For example, the resin composition may contain 10 to 99% by weight of the mixed solvent.
On the other hand, the method and equipment that can be used in the step of coating and drying the resin composition on the supporting substrate are not greatly limited. A dry film can be prepared by coating the resin composition using a method and then drying it.
A method of coating the resin composition is not particularly limited, and for example, a coating bar method can be used.
In the method for producing a photosensitive laminate, in addition to using a mixed solvent containing a high boiling point solvent having a boiling point of 115 ° C. or higher and a low boiling point solvent having a boiling point of 100 ° C. or lower, drying speed and / or drying By adjusting the temperature, the amount of microbubbles formed in the photosensitive resin layer can be greatly reduced or substantially eliminated.
More specifically, the step of drying the coated resin composition can be performed by heating means such as a hot air oven, a hot plate, a hot air circulating oven, an infrared oven, etc., at a temperature of 50° C. to 100° C., or It can be carried out at a temperature of 60°C to 90°C, a temperature of 70°C to 85°C.

The time during which the drying is performed varies depending on the drying temperature, and may be, for example, 30 seconds to 20 minutes, more specifically 1 minute to 10 minutes, or 3 minutes to 7 minutes. good.
The content regarding the alkali-developable binder resin contained in the resin composition includes the content described above for the photosensitive laminate of the one embodiment.
The alkali developable binder resin has a weight average molecular weight of 20,000 g/mol to 300,000 g/mol, or 30,000 g/mol to 150,000 g/mol, and a glass transition temperature of 20° C. or higher and 150° C. or lower. can be done.
The alkali developable binder resin may have an acid value of 100 mgKOH/g to 300 mgKOH/g.
The resin composition may further include a photopolymerizable compound including a (meth)acrylate monomer or oligomer together with the alkali-developable binder resin.
The resin composition may include 1 to 80 parts by weight of a photopolymerizable compound including a (meth)acrylate monomer or oligomer based on 100 parts by weight of the alkali-developable binder resin.
The content regarding the photopolymerizable compound includes the content described above for the photosensitive laminate of the one embodiment.
The photopolymerizable compound may be a monofunctional or multifunctional (meth)acrylate monomer or oligomer. The photopolymerizable compound may be a commonly known monofunctional or polyfunctional (meth)acrylate monomer or oligomer. The polymerizable compound can contain a trifunctional or higher polyfunctional (meth)acrylate compound.

前記化学式１において、Ｒ_４は水素、または炭素数１～１０のアルキルであり、Ｒ_５は炭素数１～１０のアルキレンであり、Ｒ_６は炭素数１～２０の中心グループを含むｐが官能基であり、ｎ２は１～２０の整数であり、ｐは前記Ｒ_６に置換される官能基数であり、３～１０の整数である。 In the method for producing a photosensitive laminate of the above embodiment, two or more solvents having different boiling points are mixed and used, and depending on the selection of the photopolymerizable compound to be used, a minute amount of microbubbles may be present or substantially It is also possible to form a photosensitive resin layer that does not exist in the film.
Specifically, the trifunctional or higher polyfunctional (meth)acrylate compound has 3 or more alkylene oxide groups having 1 to 10 carbon atoms and 3 or more (meth)acrylate functional groups in the central group having 1 to 20 carbon atoms. It can have a bonded structure.
Due to the structure of such a tri- or higher polyfunctional (meth)acrylate compound, a minute amount of air bubbles having a diameter of 1 μm or less may exist in the photosensitive resin layer, resulting in defects in the formation of fine wiring. can be reduced, high reliability can be ensured during development, and a high-density circuit can be formed.
More specifically, the trifunctional or higher polyfunctional (meth)acrylate compound may include a compound represented by Formula 1 below.

In Formula 1, R ₄ is hydrogen or C 1-10 alkyl, R ₅ is C 1-10 alkylene, R ₆ is a C 1-20 central group containing p functionalized n2 is an integer of 1 to 20; p is the number of functional groups substituted by R ₆ and is an integer of 3 to 10;

前記化学式１－１において、
Ｒ_６’は炭素数１～１０の３価の官能基であり、Ｒ_７～Ｒ_９はそれぞれ独立して、炭素数１～１０のアルキレンであり、Ｒ_１０～Ｒ_１２はそれぞれ独立して、水素、または炭素数１～１０のアルキルであり、ｎ３～ｎ５はそれぞれ独立して、１～３の整数である。
一方、前記光重合性化合物は、単官能（メタ）アクリレート化合物または二官能（メタ）アクリレート化合物をさらに含むことができる。 More specific examples of the compound of Chemical Formula 1 include compounds of Chemical Formula 1-1 below.

In the chemical formula 1-1,
R ₆ ′ is a trivalent functional group having 1 to 10 carbon atoms, R ₇ to R ₉ are each independently alkylene having 1 to 10 carbon atoms, R ₁₀ to R ₁₂ are each independently It is hydrogen or alkyl having 1 to 10 carbon atoms, and n3 to n5 are each independently an integer of 1 to 3.
Meanwhile, the photopolymerizable compound may further include a monofunctional (meth)acrylate compound or a bifunctional (meth)acrylate compound.

前記化学式２において、Ｒ_１は水素、または炭素数１～１０のアルキルであり、Ｒ_２は炭素数１～１０のアルキレンであり、Ｒ_３は炭素数１～１０のアルキルであり、ｎ１は１～２０の整数である。
前記光重合性化合物は、上述した単官能（メタ）アクリレート化合物および３官能以上の多官能（メタ）アクリレート化合物を共に含むことができる。具体的には、前記光重合性化合物は、前記炭素数１～１０のアルキレンオキシド基を含む（メタ）アクリレートを含む単官能（メタ）アクリレート化合物；および炭素数１～２０の中心グループに炭素数１～１０のアルキレンオキシド基および（メタ）アクリレート官能基がそれぞれ３個以上結合した構造を有する３官能以上の多官能（メタ）アクリレート化合物；を含むことができる。 The monofunctional (meth)acrylate compound may contain a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms.
Specifically, the monofunctional (meth)acrylate compound may include a monofunctional (meth)acrylate compound represented by Formula 2 below.

In Formula 2, R ₁ is hydrogen or alkyl having 1 to 10 carbon atoms, R ₂ is alkylene having 1 to 10 carbon atoms, R ₃ is alkyl having 1 to 10 carbon atoms, and n1 is 1. ˜20 integers.
The photopolymerizable compound may include both the above-described monofunctional (meth)acrylate compound and tri- or higher polyfunctional (meth)acrylate compound. Specifically, the photopolymerizable compound includes a monofunctional (meth)acrylate compound containing a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms; and a central group having 1 to 20 carbon atoms. trifunctional or higher polyfunctional (meth)acrylate compounds having a structure in which 1 to 10 alkylene oxide groups and 3 or more (meth)acrylate functional groups are combined;

Considering the characteristics of the photosensitive resin layer and the photosensitive laminate, the contents of the monofunctional (meth)acrylate compound and the trifunctional or higher polyfunctional (meth)acrylate compound contained in the photopolymerizable compound are adjusted. can do.
For example, the photopolymerizable compound may contain 110 parts by weight or more and 500 parts by weight or less of the polyfunctional (meth)acrylate compound having three or more functionalities with respect to 100 parts by weight of the monofunctional (meth)acrylate compound.
Also, the photopolymerizable compound may be included in an amount of 500 to 1000 parts by weight of the bifunctional (meth)acrylate compound with respect to 100 parts by weight of the tri- or higher polyfunctional (meth)acrylate compound.
The photoinitiator is a substance that initiates a chain reaction of photopolymerizable monomers by UV and other radiation, and plays an important role in curing the resin composition and the photosensitive resin layer of the photosensitive laminate. .
Compounds that can be used as the photoinitiator include anthraquinone derivatives such as 2-methylanthraquinone and 2-ethylanthraquinone; derivatives.

In addition, 2,2'-bis(2-chlorophenyl)-4,4'-5,5'-tetraphenylbisimidazole, 1-hydroxycyclohexylphenyl ketone, 2,2-dimethoxy-1,2-diphenylethane -1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-[4-morpholinophenyl]butane-1- one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1-[4-(2-hydroxymethoxy)phenyl]-2-hydroxy-2 -methylpropan-1-one, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 3,3-dimethyl-4-methoxybenzophenone, benzophenone, 1-chloro-4-propoxythioxanthone, 1 -(4-isopropylphenyl) 2-hydroxy-2-methylpropan-1-one, 1-(4-dodecylphenyl)-2hydroxy-2-methylpropan-1-one, 4-benzoyl-4'-methyldimethyl sulfide, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, butyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2-isoamyl 4-dimethylaminobenzoate, 2, 2-diethoxyacetophenone, benzyl ketone dimethyl acetal, benzyl ketone β-methoxydiethyl acetal, 1-phenyl-1,2-propyldioxime-o,o'-(2-carbonyl) ethoxy ether, methyl o-benzoyl benzoate, Bis(4-dimethylaminophenyl)ketone, 4,4'-bis(diethylamino)benzophenone, 4,4'-dichlorobenzophenone, benzyl, benzoin, methoxybenzoin, ethoxybenzoin, isopropoxybenzoin, n-butoxybenzoin, isobutoxy Benzoin, tert-butoxybenzoin, p-dimethylaminoacetophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, dibenzosuberone, α,α-dichloro -4-phenoxyacetopheno can be used as photoinitiators, but not limited thereto.

The content of the photoinitiator is 0.1 to 20% by weight or 1% to 10% by weight based on the total weight of the resin composition, based on the solid content. Sufficient sensitivity can be obtained when the content of the photoinitiator is within the above range.
If the content of the photoinitiator is too low, the light efficiency is low and a large amount of exposure is required, which may significantly reduce production efficiency. If the content of the photoinitiator is too high, the film may be brittle, and developer contamination may increase, resulting in defects such as short circuits.
In addition, the resin composition may further contain other additives, if necessary. Other additives include plasticizers such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, and diallyl phthalate in the form of phthalates; triethylene glycol diacetate and tetraethylene glycol diacetate in the form of glycol esters; and acid amide forms. p-toluenesulfonamide, benzenesulfonamide, n-butylbenzenesulfonamide; triphenyl phosphate and the like can be used.
In order to improve the handleability of the resin composition, a leuco dye or a coloring substance may be added. Examples of the leuco dyes include tris(4-dimethylamino-2-methylphenyl)methane, tris(4-dimethylamino-2methylphenyl)methane, and fluorane dyes. Among them, when leuco crystal violet is used, the contrast is good and it is preferable. When the leuco dye is contained, the content thereof may be 0.1% by weight or more and 10% by weight or less in the photosensitive resin composition. 0.1% by weight or more is preferable from the viewpoint of development of contrast, and 10% by weight or less is preferable from the viewpoint of maintaining storage stability.
Examples of coloring substances include toluenesulfonic acid monohydrate, fuchsine, phthalocyanine green, auramine base, paramagenta, crystal violet, methyl orange, Nile blue 2B, Victoria blue, malachite green, diamond green, basic blue 20, and the like. mentioned. When the coloring substance is contained, the amount added may be 0.001% by weight or more and 1% by weight or less in the photosensitive resin composition. A content of 0.001% by weight or more has the effect of improving handling properties, and a content of 1% by weight or less has the effect of maintaining storage stability.

In addition, other additives may further include thermal polymerization inhibitors, dyes, discoloring agents, adhesion promoters, and the like.
On the other hand, according to still another embodiment of the invention, there is provided a method of manufacturing a circuit board using the photosensitive laminate of the one embodiment.
The photosensitive laminate of the one embodiment can be used for applications laminated on copper clad laminates.
As an example of a manufacturing process of a circuit board or a printed circuit board (PCB), a pretreatment process is first performed in order to laminate a copper-clad laminate, which is a base material of the PCB. The pretreatment process includes drilling, deburring, surface preparation, etc. in the order of the outer layer process, and surface preparation or pickling in the inner layer process. The bristle brush and jet pumice processes are mainly used in the surface preparation process, and the pickling can be through soft etching and sulfuric acid pickling.
In order to form a circuit on a copper-clad laminate that has undergone a pretreatment process, the photosensitive laminate or dry film photoresist (hereinafter referred to as DFR) can generally be laminated on the copper layer of the copper-clad laminate. . In this process, a laminator is used to laminate the DFR photoresist layer onto the copper surface while peeling off the DFR protective film. Generally, lamination speeds of 0.5-3.5 m/min, temperatures of 100-130° C., and roller pressure heated roll pressures of 10-90 psi can be used.

The printed circuit board that has undergone the lamination process is allowed to stand for 15 minutes or longer for stabilization of the board, and then exposed to the DFR photoresist using a photomask having a desired circuit pattern. . In this process, when the photomask is irradiated with UV light, the photo-initiator contained in the irradiated portion of the photoresist initiates polymerization. First, the oxygen in the photoresist is consumed in the initial stage, then the activated monomer is polymerized to cause a cross-linking reaction, and then the polymerization reaction progresses while a large amount of the monomer is consumed. It may exist in a state in which the cross-linking reaction does not proceed.
Next, a development step is performed to remove the unexposed portions of the photoresist. In the case of alkali developable DFR, a 0.8 to 1.2 wt% potassium carbonate and sodium carbonate aqueous solution can be used as the developer. can. In this step, the unexposed portions of the photoresist are washed away in the developer by the saponification reaction of the carboxylic acid of the binder polymer and the developer, and the hardened photoresist can remain on the copper surface.
Next, a circuit is formed through different steps of inner layer and outer layer steps. In the inner layer process, a circuit is formed on the substrate by corrosion and peeling processes, and in the outer layer process, after the plating and tenting processes, etching and solder peeling proceed to form a desired circuit.
For the exposure, a commonly known light source, more specifically, an ultra-high pressure mercury lamp, a laser direct exposure apparatus, or the like may be used.

ADVANTAGE OF THE INVENTION According to this invention, the photosensitive laminated body which can reduce the defect in formation of a fine wiring, improves reliability at the time of development, and can form a high-density circuit, and the manufacturing method of the said photosensitive laminated body. and a method for manufacturing a circuit board using the photosensitive laminate can be provided.

1 is a photograph of the surface and cross section of a photosensitive resin layer of Example 1, which was confirmed with a field emission scanning electron microscope (FE-SEM, 10,000 times) using a polarizing microscope. 4 is a photograph of the surface and cross section of the photosensitive resin layer of Comparative Example 2, which was confirmed with a field emission scanning electron microscope (FE-SEM, 12,000×) using a polarizing microscope. 4 is a photograph of a defect formed by exposing the photosensitive resin layer of Comparative Example 2 to ultraviolet light and developing with alkali, which was confirmed by a field emission scanning electron microscope (FE-SEM, 3000×).

The invention is explained in more detail in the following examples. However, the following examples are merely illustrative of the present invention, and the content of the present invention is not limited by the following examples.
<Production example: Production of alkali-developable binder resin>
Production example 1
After equipping a 4-necked round-bottom flask with a mechanical stirrer and a reflux device, the inside of the flask was purged with nitrogen. 170 g of methyl ethyl ketone (MEK) and 12.5 g of methanol (MeOH) were added to the flask purged with nitrogen, and then 2.25 g of azobisisobutyronitrile (AIBN) was added. completely dissolved. 60 g of methacrylic acid (MAA), 100 g of benzyl methacrylate (BzMA), 15 g of methyl methacrylate (MMA), and 75 g of styrene (SM) as monomers. The mixture was added, the temperature was raised to 80 ° C., and then polymerized for 6 hours to obtain an alkali developable binder resin 2 (weight average molecular weight 40,000 g / mol, glass transition temperature 102 ° C., solid content 50% by weight, acid value 156 mg KOH/g) was produced.
Measurement of weight average molecular weight (Mw) of alkali developable binder resin
The alkali-developable binder resins produced in Production Example 1 and Production Example 2 had a concentration of 1.0 (w/w)% in THF (about 0.5 (w/w)% based on the solid content). was dissolved in tetrahydrofuran, filtered using a Syringe Filter of 0.45 μm Pore Size, and 20 μl was injected into GPC. Tetrahydrofuran (THF) was used as the mobile phase for GPC, flowed at a flow rate of 1.0 mL/min, and analysis was performed at 40°C. As a column, one piece of Agilent PLgel 5 μm Guard (7.5×50 mm) and two pieces of Agilent PLgel 5 μm Mixed D (7.5×300 mm) were connected in series. As a detector, Agilent 1260 Infinity II System, RI Detector was used and measured at 40°C.
Polystyrene standard samples (STD A, B, C, D) were prepared by dissolving polystyrene having various molecular weights as shown below in tetrahydrofuran at a concentration of 0.1 (w/w)%. After filtering through Syringe Filter of Size, the weight-average molecular weight (Mw) of the alkali-developable binder resin was determined using a calibration curve formed by injecting into GPC.
STD A (Mp): 791,000/27, 810/945
STD B (Mp): 282,000/10,700/580
STD C (Mp): 126,000/4,430/370
STD D (Mp): 51,200/1,920/162

<Examples and Comparative Examples: Production of photosensitive resin composition and dry film photoresist>
After dissolving a photoinitiator in an organic solvent according to the composition shown in Table 1 below, a photopolymerizable compound and an alkali-developable binder resin are added and mixed for about 1 hour using a mechanical stirrer to form a photosensitive resin. A composition was produced.
The photosensitive resin composition obtained above was coated on a 16 μm PET film using a coating bar. The coated photosensitive resin composition layer is dried using a hot air oven at a drying temperature of 80° C., a drying time of 5 minutes, and a thickness of the photosensitive resin layer after drying of 25 μm. Met.
A protective film (polyethylene) was laminated on the dried photosensitive resin composition layer to prepare a photosensitive laminate (dry film photoresist).

[Comparative Example 2: Production of photosensitive resin composition and dry film photoresist]
Based on the identification codes [0088] and [0093] of the specification of Patent Document 1 (Patent Publication No. 2006-106287), an experiment was conducted to reproduce Example 4 of Patent Document 1.
1. Production of photosensitive resin composition Based on the items described in Example 4 of Patent Document 1, the following components were added to 300 parts by weight of the "alkali-developable binder resin" obtained in Production Example 1 of the present specification. A photosensitive resin composition was prepared by mixing for about 1 hour using a mechanical stirrer.
<Components of the photosensitive resin composition>
(1) 2,2-bis(4-(methacryloxypentaethoxy)phenyl)propane 100 parts by weight (2) EO, PO-modified urethane dimethacrylate 50 parts by weight (3) polypropylene glycol diacrylate (number of propylene glycol chains: 7) 50 parts by mass (4) Photopolymerization initiator: 25 parts by mass of benzophenone, 1.0 part by mass of 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer and 1.0 part by mass of diethylaminobenzophenone (5 ) Photochromic agent 5.0 parts by mass (6) Dye 0.15 parts by mass (7) Mixed solvent: acetone (boiling point 56°C) 477 parts by mass, toluene (boiling point 110°C) 26.5 parts by mass and propylene glycol monomethyl ether (boiling point 146.4° C.) 26.5 parts by mass [weight ratio of low boiling solvent having a boiling point of 100° C. or lower:high boiling solvent having a boiling point of 115° C. or higher=19:1]

2. Preparation of Dry Film Photoresist The photosensitive resin composition obtained above was coated on a 25 μm PET film using a coating bar. The coated photosensitive resin composition layer is dried using a hot air oven at a drying temperature of 80° C., a drying time of 5 minutes, and a thickness of the photosensitive resin layer after drying of 25 μm. Met.
<Experimental example>
The physical properties of the dry film photoresists prepared in Examples and Comparative Examples were measured according to the following methods, and the results are shown in Table 2.
1. Measurement of exposure dose (unit: mJ/cm ² ) The dry film photoresists prepared in the above examples and comparative examples were laminated on a brush-polished copper-clad laminate having a thickness of 1.6 mm. . At this time, the lamination was carried out using Hakuto MACH 610i with a substrate preheating roll temperature of 120° C., a laminator roll temperature of 115° C., a roll pressure of 4.0 kgf/cm ² and a roll speed of 2.0 min/m.
A dry film photoresist laminated on a copper-clad laminate was exposed to a wavelength of 405 nm using a 41-step tablet from Stouffer Graphic Arts Equipment using ORC's FDi-3 at an exposure dose that resulted in 15 remaining steps. After irradiating with ultraviolet rays, it was allowed to stand for 15 minutes. After that, development was performed with a 1.0 wt % aqueous solution of Na ₂ CO ₃ under the development conditions of the spray injection method. At this time, the amount of energy at which the predetermined number of remaining steps becomes 15 was measured.
2. Measurement of 1:1 resolution (unit: μm) The dry film photoresists produced in the above examples and comparative examples were applied to a brush-polished copper-clad laminate having a thickness of 1.6 mm. laminated. At this time, the lamination was carried out using Hakuto MACH 610i with a substrate preheating roll temperature of 120° C., a laminator roll temperature of 115° C., a roll pressure of 4.0 kgf/cm ² and a roll speed of 2.0 min/m.
After developing the laminate, data formed at intervals of 0.5 μm from 4 to 20 μm so that the width of the circuit line and the space between the circuit lines are 1:1. was used to irradiate UV rays with a wavelength of 405 nm using a 41-step tablet from Stouffer Graphic Arts Equipment using a 41-step tablet from Stouffer Graphic Arts Equipment Co., Ltd., with a wavelength of 405 nm, and then left for 15 minutes. . After that, development was performed with a 1.0 wt % aqueous solution of Na ₂ CO ₃ under the development conditions of the spray injection method.
Resolution was then determined using a ZEISS AXIOPHOT Microscope, with the spacing between circuit and non-circuit lines measured as 1:1.

3. Confirmation of air bubbles (unit: number/mm ² ) After removing the PET film and PE film from the dry film photoresists prepared in the above examples and comparative examples, the photosensitive resin layer (unit: number/mm 2 ) was examined using a polarizing microscope. The number of bubbles (number/mm ² ) having a diameter of less than 1 μm within the area (1 mm*1 mm) was confirmed.

4. Confirmation of defects (unit: number/mm ² ) after exposure/development The dry film photoresists produced in the above Examples and Comparative Examples were brush-polished and coated with a 1.6 mm thick copper clad film. Laminated to a laminate. At this time, the lamination was carried out using Hakuto MACH 610i with a substrate preheating roll temperature of 120° C., a laminator roll temperature of 115° C., a roll pressure of 4.0 kgf/cm ² and a roll speed of 2.0 min/m.
After development on the laminate, FDi-3 from ORC, 41 from Stouffer Graphic Arts Equipment, Inc., such that the width of the circuit line and the space between the circuit line is 14 μm:14 μm. After irradiating ultraviolet rays with a wavelength of 405 nm using a step step tablet with an exposure amount such that the number of remaining steps becomes 15 steps, the substrate was allowed to stand for 15 minutes. After that, development was performed with a 1.0 wt % aqueous solution of Na ₂ CO ₃ under the development conditions of the spray injection method.
For each of the developed dry film photoresists produced in the above Examples and Comparative Examples, the upper and lower surfaces of the resist were observed within a unit area (1 mm*1 mm) using an electron microscope, and the thickness was 0.5 μm. The number of defects (defects) of 3 μm or less (number/mm ² ) present was confirmed, and the surfaces and cross sections of the photosensitive resin layers obtained in Examples and Comparative Examples were examined with a field emission scanning electron microscope (FE- Observation was made using a SEM (manufactured by Hitachi, 3000 times magnification).

As can be seen from Table 2 and FIG. 1, in the photosensitive resin layer of the photosensitive laminate of the example, 1 cell/ ^mm2 or less having a diameter of less than 1 μm is present, and 1 μm to 5 μm is present. It was also confirmed that there were no giant bubbles with diameters below.
Further, in the photosensitive resin layer of the above example, even after being exposed to ultraviolet light and developed with an alkaline solution, defects having a diameter of 0.5 μm to 3 μm are not substantially generated, or It was confirmed that 1 piece/mm ² or less was generated.
A small amount of air bubbles having a diameter of less than 1 μm are present in the photosensitive resin layer of the above embodiment, thereby reducing defects in the formation of fine wiring when manufacturing a circuit board using the photosensitive laminate. It was also observed that high density and sensitivity can be achieved while ensuring high reliability, and finer wiring can be formed.
On the other hand, in the photosensitive resin laminate of Comparative Example 1, it was confirmed that it was difficult to achieve the resolution of the example level even if the same level of energy as in the example was used. It was confirmed that it is difficult to realize the resolution of the embodiment level even if the energy reaches 350 mJ/cm ² in the body.
Furthermore, in the dry film photoresists of Comparative Examples 1 and 2, 15 or more "bubbles with a diameter of less than 1 μm" were generated/mm ² , and as confirmed from FIG. After developing with an alkaline solution, it was confirmed that a plurality of defects (8/mm ² or more) having a diameter of 0.5 μm to 3 μm appeared.

Claims (28)

a support substrate; and a photosensitive resin layer containing a photopolymerizable compound containing a polyfunctional (meth)acrylate compound having three or more functionalities and an alkali-developable binder resin;
A photosensitive laminate in which 5 cells/mm ² or less having a diameter of less than 1 μm are present in the photosensitive resin layer. 2. The photosensitive laminate according to claim 1, wherein the photosensitive resin layer does not contain air bubbles having a diameter of 1 μm to 5 μm or less. Within 50% of the total thickness of the photosensitive resin layer from the opposite side of the interface between the supporting substrate and the photosensitive resin layer, there are 3 or less bubbles/ ^mm2 having a diameter of less than 1 μm. , The photosensitive laminate of claim 1. The thickness of the supporting substrate is 1 μm to 100 μm,
2. The photosensitive laminate according to claim 1, wherein the photosensitive resin layer has a thickness of 1 μm to 100 μm. 2. The photosensitive laminate according to claim 1, wherein the photosensitive resin layer has 3 defects/mm ² or less having a cross-sectional diameter of 0.3 μm to 4 μm after UV exposure and alkali development. The trifunctional or higher polyfunctional (meth)acrylate compound is
2. The photosensitive laminate according to claim 1, having a structure in which three or more alkylene oxide groups having 1 to 10 carbon atoms and three or more (meth)acrylate functional groups are bonded to a central group having 1 to 20 carbon atoms. The photosensitive laminate according to claim 1, wherein the tri- or higher polyfunctional (meth)acrylate compound includes a compound represented by Chemical Formula 1 below:

In the chemical formula 1,
R ₄ is hydrogen or alkyl having 1 to 10 carbon atoms,
R ₅ is alkylene having 1 to 10 carbon atoms,
R ₆ is a functional group containing a central group of 1 to 20 carbon atoms,
n2 is an integer from 1 to 20,
p is the number of functional groups substituted for R ₆ and is an integer of 3-10. The photosensitive laminate according to claim 1, wherein the photopolymerizable compound further comprises a monofunctional (meth)acrylate compound or a bifunctional (meth)acrylate compound. 9. The photosensitive laminate according to claim 8, wherein the monofunctional (meth)acrylate compound contains a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms. The photopolymerizable compound is a monofunctional (meth)acrylate compound containing a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms; and an alkylene oxide having 1 to 10 carbon atoms in the central group having 1 to 20 carbon atoms. 9. The photosensitive laminate according to claim 8, comprising a trifunctional or higher polyfunctional (meth)acrylate compound having a structure in which three or more groups and three or more (meth)acrylate functional groups are combined. 9. The photopolymerizable compound according to claim 8, wherein the trifunctional or higher polyfunctional (meth)acrylate compound is contained in an amount of 110 to 500 parts by weight with respect to 100 parts by weight of the monofunctional (meth)acrylate compound. photosensitive laminate. 9. The photopolymerizable compound according to claim 8, wherein the difunctional (meth)acrylate compound is included in an amount of 500 parts by weight or more and 1000 parts by weight or less with respect to 100 parts by weight of the trifunctional or higher polyfunctional (meth)acrylate compound. Photosensitive laminate. 2. The photosensitive laminate according to claim 1, wherein the alkali-developable binder resin has a weight average molecular weight of 20,000 g/mol to 300,000 g/mol and a glass transition temperature of 20° C. or higher and 150° C. or lower. The photosensitive laminate according to claim 1, wherein the alkali-developable binder resin has an acid value of 100 mgKOH/g or more and 300 mgKOH/g. A method for manufacturing a circuit board using the photosensitive laminate according to claim 1 . A mixed solvent containing a high boiling point solvent having a boiling point of 115° C. or higher and a low boiling point solvent having a boiling point of 100° C. or lower; a photopolymerizable compound containing a trifunctional or higher polyfunctional (meth)acrylate compound; an alkali developable binder resin; and a photoinitiator;
The method for producing a photosensitive laminate, wherein the mixed solvent contains the high boiling point solvent having a boiling point of 115° C. or higher and the low boiling point solvent having a boiling point of 100° C. or lower in a weight ratio of 1:2 to 1:18. 17. The photosensitive laminate according to claim 16, wherein the mixed solvent contains the high boiling point solvent having a boiling point of 115° C. or higher: the low boiling point solvent having a boiling point of 100° C. or lower in a weight ratio of 1:3 to 1:15. body manufacturing method. The high boiling point solvent having a boiling point of 115° C. or higher includes butanol, dimethylformamide, N-methyl-2-pyrrolidone, gamma-butyrolactone, butyl carbitol, butyl cellosolve, methyl cellosolve, butyl acetate, diethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, and diethylene glycol. The group consisting of diethyl ether, dipropylene glycol dimethyl ether, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether propionate, dipropylene glycol dimethyl ether, cyclohexanone and propylene glycol monomethyl ether acetate (PGMEA) 17. The method for producing a photosensitive laminate according to claim 16, comprising one or more selected organic solvents. 17. The photosensitive laminate according to claim 16, wherein the low boiling point solvent having a boiling point of 100°C or less comprises one or more organic solvents selected from the group consisting of methyl ethyl ketone, methanol, ethanol, acetone, tetrahydrofuran and isopropyl alcohol. body manufacturing method. The trifunctional or higher polyfunctional (meth)acrylate compound is
17. The method for producing a photosensitive laminate according to claim 16, which has a structure in which three or more alkylene oxide groups having 1 to 10 carbon atoms and three or more (meth)acrylate functional groups are bonded to the central group having 1 to 20 carbon atoms. 17. The method for producing a photosensitive laminate according to claim 16, wherein the tri- or higher polyfunctional (meth)acrylate compound includes a compound represented by Chemical Formula 1 below:

In the chemical formula 1,
R ₄ is hydrogen or alkyl having 1 to 10 carbon atoms,
R ₅ is alkylene having 1 to 10 carbon atoms,
R ₆ is a functional group containing a central group of 1 to 20 carbon atoms,
n2 is an integer from 1 to 20,
p is the number of functional groups substituted for R ₆ and is an integer of 3-10. 17. The method for producing a photosensitive laminate according to claim 16, wherein the photopolymerizable compound further includes a monofunctional (meth)acrylate compound or a bifunctional (meth)acrylate compound. 23. The method for producing a photosensitive laminate according to claim 22, wherein the monofunctional (meth)acrylate compound contains a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms. The photopolymerizable compound is a monofunctional (meth)acrylate compound containing a (meth)acrylate containing an alkylene oxide group having 1 to 10 carbon atoms; and an alkylene oxide having 1 to 10 carbon atoms in the central group having 1 to 20 carbon atoms. 23. The method for producing a photosensitive laminate according to claim 22, comprising a trifunctional or higher polyfunctional (meth)acrylate compound having a structure in which three or more groups and three or more (meth)acrylate functional groups are combined. 23. The photopolymerizable compound according to claim 22, wherein the trifunctional or higher polyfunctional (meth)acrylate compound is contained in an amount of 110 to 500 parts by weight with respect to 100 parts by weight of the monofunctional (meth)acrylate compound. A method for producing a photosensitive laminate. 23. The photopolymerizable compound according to claim 22, wherein the difunctional (meth)acrylate compound is included in an amount of 500 parts by weight or more and 1000 parts by weight or less with respect to 100 parts by weight of the trifunctional or higher polyfunctional (meth)acrylate compound. A method for producing a photosensitive laminate. The method for producing a photosensitive laminate according to claim 16, wherein the alkali-developable binder resin has a weight average molecular weight of 20,000 g/mol to 300,000 g/mol and a glass transition temperature of 20°C or higher and 150°C or lower. . 17. The method for producing a photosensitive laminate according to claim 16, wherein the alkali-developable binder resin has an acid value of 100 mgKOH/g or more and 300 mgKOH/g.

Images