Wiring board, positive photosensitive resin composition for forming light-blocking layer, light-blocking layer transfer film, and wiring board manufacturing method

Abstract

Provided are a wiring base material having excellent design visibility, and a positive photosensitive resin composition for forming a light-blocking layer suitable for the wiring base material. The wiring base material has, on a transparent base material, a multilayer pattern of an opaque wiring electrode and a light-blocking layer containing a resin and a colored component. An average value R1 of internal diffuse reflectance at a wavelength of 540-570 nm measured from the light-blocking layer side of a multilayer pattern forming portion is 0.03-0.11%.

Description

Wiring board, positive photosensitive resin composition for forming light-shielding layer, light-shielding layer transfer film, and method for manufacturing wiring board

[0001] The present invention relates to a wiring board, a positive photosensitive resin composition for forming a light-shielding layer, a light-shielding layer transfer film, and a method for producing a wiring substrate.

[0002] Touch panels, which have become widely used as input devices in recent years, consist of a display unit such as a liquid crystal panel and a touch panel sensor that detects information input at a specific position. While transparent wiring electrodes have generally been used as the wiring electrodes in touch panel sensors to reduce their visibility, opaque wiring electrodes made of metallic materials have become more common in recent years due to increased sensitivity and larger screen sizes. Opaque wiring electrodes made of metallic materials have a problem of being easily visible due to their metallic luster. As a method for reducing the visibility of opaque wiring electrodes, a wiring board has been proposed that includes a transparent substrate, an opaque wiring electrode patterned on at least one side of the transparent substrate, and a transparent protective layer formed on the transparent substrate and the opaque wiring electrode, where the internal reflectance R1 at the opaque wiring electrode formation portion measured from the transparent protective layer side of the wiring board is 0.1% or less, and the refractive index n1 of the transparent substrate and the refractive index n2 of the transparent protective layer satisfy a specific relationship, particularly a wiring board that includes a light-shielding layer on top of the opaque wiring electrode (see, for example, Patent Document 1). Furthermore, as positive-type photosensitive compositions to be used in light-shielding layers, there have been proposed photosensitive resin compositions containing a pigment, a novolac resin, an acrylic resin having a carboxy group, a photoacid generator, and an amine-based dispersant (see, for example, Patent Document 2), and positive-type photosensitive resin compositions containing an alkali-soluble resin (A) having an acrylic group and / or a methacrylic group in a side chain, a photosensitizer (B), and a colorant (C) (see, for example, Patent Document 3).

[0003] International Publication No. 2022 / 130803 Japanese Patent Application Laid-Open No. 2021-139971 International Publication No. 2021 / 149410

[0004] The light-shielding layers disclosed in Patent Documents 1 to 3 can reduce the visibility of opaque wiring electrodes due to their metallic luster. However, in bright locations, such as in automotive applications, external light is easily reflected, and light scattering on the surface of the wiring substrate tends to cause the laminated pattern-forming portion to appear whitish and cloudy compared to the non-laminated pattern-forming portion and the decorative portion. In applications where jet black is required from the standpoint of design, it is necessary to reduce this whitish cloudiness, i.e., to improve the visibility of the design.

[0005] Therefore, an object of the present invention is to provide a wiring substrate having excellent design visibility and a positive photosensitive resin composition for forming a light-shielding layer suitable for the wiring substrate.

[0006] In order to solve the above problems, the present invention mainly has the following configuration: <1> A wiring substrate having, on a transparent substrate, a laminate pattern of an opaque wiring electrode and a light-shielding layer containing a resin and a coloring component, wherein the average internal diffuse reflectance R1 at a wavelength of 540 to 570 nm measured from the light-shielding layer side of the laminate pattern-forming portion is 0.03 to 0.11%. <2> The wiring substrate according to <1>, wherein the average internal diffuse reflectance R1 [%] at a wavelength of 540 to 570 nm measured from the light-shielding layer side of the laminate pattern-forming portion, the average internal diffuse reflectance R2 [%] at a wavelength of 540 to 570 nm of the laminate pattern-non-forming portion, the line width W [μm] of the laminate pattern, and the ratio S of the laminate pattern area to the area of ​​the laminate pattern-forming portion (laminate pattern area / laminate pattern area) satisfy the relationship of the following formula (1): 0.0≦((R1×W)−(R2×(1−S))) / S≦7.0 (1) <3> The wiring substrate according to <1> or <2>, wherein the thickness T1 [μm] of the light-shielding layer is 0.2 to 2.0. <4> A positive photosensitive resin composition for forming a light-shielding layer, comprising (a) an alkali-soluble resin, (b) a quinone diazide compound, (c) metal nitride particles, and (d) a purple organic pigment. <5> The positive photosensitive resin composition for forming a light-shielding layer according to <4>, wherein the content of the (c) metal nitride particles is 2.0 to 6.0 vol%. <6> The positive photosensitive resin composition for forming a light-shielding layer according to <4> or <5>, further comprising (e) a red organic pigment. <7> The positive photosensitive resin composition for forming a light-shielding layer according to <6>, in which the total content of (c) metal nitride particles, (d) purple organic pigment, and (e) red organic pigment is 5 to 15 volume %. <8> A light-shielding layer transfer film having, on a release film, a light-shielding layer formed from the positive photosensitive resin composition for forming a light-shielding layer according to any one of <4> to <7>. <9> The light-shielding layer transfer film according to <8>, in which the thickness T1' [μm] of the light-shielding layer is 0.3 to 2.0.<10> A method for producing a wiring substrate according to any one of <1> to <3>, comprising the steps of: forming an opaque wiring electrode on a transparent substrate; applying the positive photosensitive resin composition for forming a light-shielding layer according to any one of <4> to <7> to a surface on which the opaque wiring electrode is formed; and exposing the photosensitive resin composition coating film from a surface opposite to the coated surface using the opaque wiring electrode as a mask, and developing it, thereby patterning the photosensitive resin composition coating film to form a laminate pattern of the opaque wiring electrode and the light-shielding layer. <11> A method for producing a wiring substrate according to any one of <1> to <3>, comprising the steps of forming an opaque wiring electrode on a transparent substrate; transferring the light-shielding layer of the light-shielding layer transfer film according to <8> or <9> to the surface on which the opaque wiring electrode is formed; and exposing the light-shielding layer from a surface opposite to the transfer surface using the opaque wiring electrode as a mask, and developing it, thereby patterning the light-shielding layer to form a laminate pattern of the opaque wiring electrode and the light-shielding layer.

[0007] The wiring substrate of the present invention has excellent design visibility. The positive photosensitive resin composition for forming a light-shielding layer of the present invention can provide a wiring substrate having excellent design visibility.

[0008] Fig. 1 is a schematic diagram showing an example of the configuration of a wiring substrate of the present invention. Fig. 2 is a schematic diagram showing another example of the configuration of a wiring substrate of the present invention. Fig. 3 is a schematic diagram showing an example of the configuration of a substrate for internal diffuse reflectance evaluation in the present invention. Fig. 4 is a schematic diagram showing an electrode pattern for visibility evaluation used in Examples and Comparative Examples. Fig. 5 is a schematic diagram of a mesh pattern of a negative-type mask used in Examples and Comparative Examples.

[0009] First, a wiring substrate will be described as a first aspect of the present invention. The wiring substrate of the present invention has an opaque wiring electrode on a transparent substrate and a light-shielding layer in a portion corresponding to the opaque wiring electrode. That is, it has a laminated pattern of an opaque wiring electrode and a light-shielding layer. The light-shielding layer may be provided on the opaque wiring electrode, or the opaque wiring electrode may be provided on the light-shielding layer. The light-shielding layer suppresses light reflection and light scattering of the opaque wiring electrode, thereby reproducing a highly decorative jet black and improving design visibility. Furthermore, a transparent protective layer may be provided thereon. The presence of the transparent protective layer protects the surfaces of the opaque wiring electrode and the light-shielding layer and prevents scratches, etc. Here, "transparent" refers to a light transmittance of 50% or more at a wavelength of 550 nm, and "opaque" refers to a light transmittance of less than 50% at a wavelength of 550 nm. The light transmittance at a wavelength of 550 nm can be measured using a UV-visible spectrophotometer (U-3310: manufactured by Hitachi High-Technologies Corporation).

[0010] Fig. 1 shows a schematic diagram of one example of the configuration of a wiring substrate of the present invention. A wiring substrate 4 has an opaque wiring electrode 2 on a transparent substrate 1, and a light-shielding layer 3 on the opaque wiring electrode 2. Fig. 2 shows another example of the configuration of a wiring substrate of the present invention. The wiring substrate 4 has a light-shielding layer 3 on a transparent substrate 1, and the opaque wiring electrode 2 on the light-shielding layer 3.

[0011] The wiring substrate of the present invention has a laminated pattern of an opaque wiring electrode and a light-shielding layer containing a resin and a coloring component. In the present invention, the average internal diffuse reflectance R1 at wavelengths of 540 to 570 nm measured from the light-shielding layer side of the laminated pattern-forming portion is 0.03 to 0.11%. Here, the laminated pattern-forming portion refers to the region where the laminated pattern is formed, and includes not only the portion corresponding to the laminated pattern but also the non-laminated pattern portion located between adjacent laminated patterns spaced apart by less than 1 mm. More specifically, for example, in the case of a striped laminated pattern, the laminated pattern-forming portion includes the portion corresponding to the striped laminated pattern with a pitch of less than 1 mm and the non-laminated pattern portion sandwiched between the laminated patterns. For example, in the case of a mesh-shaped laminated pattern shown in FIG. 5, the laminated pattern-forming portion includes the portion corresponding to the mesh-shaped laminated pattern with a mesh pitch of less than 1 mm (laminated pattern portion 12) and the non-laminated pattern portion (non-laminated pattern portion 13) surrounded by the mesh-shaped laminated pattern. On the other hand, the non-laminated pattern portion where the distance between adjacent laminated patterns is 1 mm or more is referred to as the non-laminated pattern-forming portion. As mentioned above, while conventional light-shielding layers can reduce the visibility of opaque wiring electrodes due to their metallic luster, they tend to cause the laminate pattern formation portion to appear cloudy and whitish due to light scattering on the wiring substrate surface, especially in bright locations. The inventors' research has revealed that while laminating conventional light-shielding layers on opaque wiring electrodes can reduce the total reflectance (SCI) of the laminate pattern formation portion, the diffuse reflectance (SCE) is higher than that of transparent wiring electrodes such as ITO. Therefore, the inventors investigated the relationship between diffuse reflectance and the issue of design visibility due to light scattering on the wiring substrate surface, and focused on diffuse reflectance in the wavelength range of 540 to 570 nm, where visibility is high. The average internal diffuse reflectance R1 at wavelengths of 540 to 570 nm, measured from the light-shielding layer side of the laminate pattern formation portion, is an index of diffuse reflectance in the wavelength range with high visibility. By setting R1 to 0.03 or more, the difference in diffuse reflectance between the laminate pattern formation portion and the laminate pattern non-formation portion can be prevented from being visible. R1 is preferably equal to or greater than 0.04.On the other hand, by setting R1 to 0.11% or less, it is possible to suppress the whitish clouding of the laminated pattern formation portion due to light scattering on the wiring substrate surface even in particularly bright places, reproduce a highly attractive jet black color, and improve the visibility of the design.

[0012] Here, the internal diffuse reflectance corresponds to the diffuse reflectance obtained by eliminating the reflection caused by the difference in refractive index at the interface between the wiring substrate surface and air. Figure 3 shows a schematic diagram of an example of the configuration of a substrate for evaluating the internal diffuse reflectance of a wiring substrate. The wiring substrate 4 has a laminated pattern of an opaque wiring electrode 2 and a light-shielding layer 3 on a transparent substrate 1, and further has a transparent protective layer 6. An anti-reflection film 8 is attached to the light-shielding layer-forming surface of the wiring substrate (here, on the transparent protective layer 6) via an adhesive layer 7, and a black film 9 is attached to the surface of the transparent substrate 1 opposite the light-shielding layer via an adhesive layer 7 to prepare a substrate for evaluating internal diffuse reflectance 16, which reduces reflection at the interface between the wiring substrate and air. Note that, although not shown, if the laminated pattern of the light-shielding layer and the opaque wiring electrode on the transparent substrate has a light-shielding layer on the transparent substrate side, an anti-reflection film is attached to the transparent substrate via a transparent adhesive layer, and a black film is attached to the transparent protective layer via an adhesive layer to prepare a substrate for evaluating internal diffuse reflectance, which reduces reflection at the interface between the wiring substrate and air. For the laminated pattern forming portion of the obtained substrate for internal diffuse reflectance evaluation, the diffuse reflectance at wavelengths of 540, 550, 560, and 570 nm is measured from the light-shielding layer forming side, i.e., the anti-reflection film 8 side in the case of the configuration shown in FIG. 3, using a colorimetric system or the like, and the average value is calculated, thereby allowing the average internal diffuse reflectance R1 to be calculated.

[0013] The diffuse reflectance is affected by the reflectance of the material forming the light-shielding layer itself, as well as the line width, area, and uneven shape of the light-shielding layer. For example, when the area of ​​the light-shielding layer is the same, a narrower line width W tends to result in a wiring substrate surface closer to a diffusing surface, resulting in a higher internal diffuse reflectance due to the uneven shape of the light-shielding layer. Examples of methods for achieving R1 of 0.03 to 0.11% include a method in which the ratio S of the laminate pattern area to the area of ​​the laminate pattern forming portion (laminate pattern area / laminate pattern forming portion area, hereinafter referred to as "occupancy rate"), the line width W of the laminate pattern, and the thickness T1 of the light-shielding layer are set within the preferred ranges described below, and a method in which the light-shielding layer is formed from the positive photosensitive resin composition for forming a light-shielding layer of the present invention described below. Among these, the method of forming the light-shielding layer from the positive photosensitive resin composition for forming a light-shielding layer of the present invention described below is preferred because it has fewer restrictions on the wiring pattern.

[0014] In the wiring substrate of the present invention, it is preferable that the average internal diffuse reflectance R1 [%], the average internal diffuse reflectance R2 [%] at a wavelength of 540 to 570 nm in the laminate pattern non-forming portion, and the occupancy rate S satisfy the relationship of the following formula (1): 0.0≦((R1×W)−(R2×(1−S))) / S≦7.0 (1) In the laminate pattern forming portion, the diffuse reflectance is affected by reflection and scattering from the wiring surface in the region with area ratio S (laminate pattern portion) and reflection and scattering from the non-wiring surface in the region with area ratio (1−S) (non-laminate pattern portion). Furthermore, as described above, the diffuse reflectance is affected by the area and uneven shape of the light-shielding layer. In the above formula (1), (R1×W) is an index of diffuse reflectance in the laminate pattern forming portion excluding the influence of line width. On the other hand, in the non-laminate pattern portion, the diffuse reflectance is affected by reflection and scattering from the non-wiring surface in the region with area ratio (1−S). The average value R2 of the internal diffuse reflectance in the wavelength range of 540 to 570 nm of the laminate pattern non-forming portion is an index of the diffuse reflectance in the wavelength region with high visibility, and (R2 x (1-S)) in the above formula (1) is an index of the diffuse reflectance of the non-wiring surface in the laminate pattern forming portion. Then, we focused on the diffuse reflectance of the wiring surface per unit area, which is the difference between these values ​​(i.e., the diffuse reflectance of the wiring surface in the laminate pattern forming portion) divided by the area ratio S. When these satisfy the relationship of the above formula (1), there are fewer constraints on the wiring pattern, and the design visibility can be further improved. Here, the average value R2 of the internal diffuse reflectance in the wavelength range of 540 to 570 nm of the laminate pattern non-forming portion can be calculated in the same manner as the above-mentioned R1 for the laminate pattern non-forming portion. The value of ((R1 x W) - (R2 x (1-S))) / S (hereinafter sometimes referred to as "diffuse reflectance per unit area") is more preferably 6.0 or less. An example of a method for satisfying the above formula (1) is a method in which a light-shielding layer is formed from the positive photosensitive resin composition for forming a light-shielding layer of the present invention, which will be described later.

[0015] The opaque wiring electrode preferably has a light transmittance of 25% or less at a wavelength of 550 nm. It also preferably has light-shielding properties against the exposure light used in the method for forming a light-shielding layer described below. Specifically, the light transmittance at a wavelength of 365 nm is preferably 15% or less. By setting the light transmittance at a wavelength of 365 nm to 15% or less, the function as a mask can be improved in the method for forming a light-shielding layer described below, and the desired light-shielding layer can be formed with greater processability. The light transmittance of the opaque wiring electrode can be measured using a microsurface spectrophotometer (VSS 400: manufactured by Nippon Denshoku Industries Co., Ltd.) for a square opaque wiring electrode with a side length of 0.1 mm or more.

[0016] Examples of materials constituting the opaque wiring electrode include metals such as silver, gold, copper, platinum, lead, tin, nickel, aluminum, tungsten, molybdenum, chromium, titanium, and indium, and conductive substances such as alloys of these. Two or more of these may be used. Among these, silver, copper, and the like are preferred from the viewpoint of conductivity.

[0017] The raw material used to form the opaque wiring electrode is preferably conductive particles containing the above-mentioned conductive material, and the shape thereof is preferably spherical. The average particle size of the conductive particles is preferably 0.03 μm or more from the viewpoint of improving the dispersibility of the conductive particles. On the other hand, the average particle size of the conductive particles is preferably 1.0 μm or less from the viewpoint of sharpening the edges of the pattern of the opaque wiring electrode. The average particle size of the conductive particles can be determined by observing the conductive particles at a magnification of 15,000 times using a scanning electron microscope (SEM) or a transmission electron microscope (TEM), measuring the major axis length of each of 100 randomly selected conductive particles, and calculating the number average value.

[0018] The opaque wiring electrode may contain an organic component in addition to the aforementioned conductive material. The opaque wiring electrode may be formed, for example, from a cured product of a photosensitive conductive composition containing conductive particles, an alkali-soluble resin, and a photopolymerization initiator. In this case, the opaque wiring electrode contains the photopolymerization initiator and / or its photodecomposition product. The photosensitive conductive composition may contain additives such as a heat curing agent and a leveling agent, as necessary.

[0019] Examples of the pattern shape of the opaque wiring electrode include a mesh shape and a stripe shape. Examples of the mesh shape include a lattice shape with unit shapes such as triangles, squares, polygons, and circles, or a lattice shape formed by a combination of these unit shapes. Among these, a mesh shape is preferred from the viewpoint of achieving uniform conductivity of the pattern. It is more preferred that the opaque wiring electrode be a metal mesh made of the above-mentioned metal and having a mesh-like pattern. When the opaque wiring electrode has a mesh-like pattern, the occupancy rate S can be reduced by increasing the mesh pitch.

[0020] The thickness T2 [μm] of the opaque wiring electrode is preferably 0.1 or more, more preferably 0.3 or more, from the viewpoint of improving conductivity. On the other hand, the thickness T2 [μm] of the opaque wiring electrode is preferably 10 or less, more preferably 5.0 or less, and even more preferably 3.0 or less, from the viewpoint of forming finer wiring. Furthermore, when the wiring substrate has a transparent protective layer, by setting the thickness T2 [μm] of the opaque wiring electrode to 10 or less, unevenness on the transparent substrate can be reduced and the generation of bubbles due to the unevenness when the transparent protective layer is laminated can be suppressed. Note that T2 can be measured using a stylus-type profilometer.

[0021] The line width of the pattern of the opaque wiring electrode is preferably 1 μm or more, more preferably 1.5 μm or more, and even more preferably 2 μm or more, from the viewpoint of improving conductivity. On the other hand, when the pattern shape of the opaque wiring electrode is the same, the line width of the pattern is preferably 10 μm or less, more preferably 8 μm or less, from the viewpoint of further reducing the value of the internal diffuse reflectance R1 and further improving the visibility of the design. Here, the line width of the pattern of the opaque wiring electrode can be determined by using an optical microscope to observe the laminated pattern formation portion at a magnified scale, measuring the line width of the opaque wiring electrode at three randomly selected locations, and calculating the average value.

[0022] The wiring substrate of the present invention has a light-shielding layer containing a resin and a coloring component.

[0023] The resin is preferably an alkali-soluble resin. Examples of alkali-soluble resins include resins having hydroxyl groups and / or carboxyl groups. Among these, resins having phenolic hydroxyl groups are preferred. Examples of resins having phenolic hydroxyl groups include novolac resins such as phenol novolac resins and cresol novolac resins, polymers of monomers having phenolic hydroxyl groups, and copolymers of monomers having phenolic hydroxyl groups with styrene, acrylonitrile, acrylic monomers, and the like. Two or more of these may be contained.

[0024] Examples of coloring components include pigments such as inorganic pigments and organic pigments, dyes, etc., with pigments being preferred because of their excellent weather resistance.

[0025] Examples of organic pigments include soluble azo pigments, insoluble azo pigments, metal complex azo pigments, phthalocyanine pigments, condensed polycyclic pigments, black organic pigments such as C.I. Pigment Black 31 and 32, purple organic pigments such as C.I. Pigment Violet 19, 23, 29, 30, 32, 36, 37, 38, 39, 40, and 50, and red organic pigments such as C.I. Pigment Red 9, 48, 97, 122, 123, 144, 149, 166, 168, 177, 179, 180, 190, 192, 196, 202, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 254, 255, 264, and 265. blue organic pigments such as C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 60, 64, 65, 75, 79, 80, etc., yellow organic pigments such as C.I. Pigment Yellow 12, 13, 17, 20, 24, 74, 83, 86, 93, 95, 109, 110, 117, 120, 125, 129, 138, 139, 150, 151, 175, 180, 181, 185, 192, 194, 199, etc., green organic pigments such as C.I. Pigment Green 7, 36, 37, etc., C.I. Pigment Orange 1, 5, 13, 14, 16, 17, 24, 34, 36, 38, 40, 43, 46, 49, 51, 55, 59, 61, 63, 64, 71, and 73.

[0026] Examples of inorganic pigments include carbon black, graphite, metal nitride particles such as titanium nitride and zirconium nitride, pine soot, iron oxides such as hematite, goethite and magnetite, chromium, lead, and composites of these metals. Among these, metal nitride particles are preferred because of their high transparency to exposure light.

[0027] From the viewpoint of setting the average value R1 of the internal diffuse reflectance within the aforementioned range, the coloring component preferably absorbs light in the wavelength range of 540 to 570 nm. Examples of coloring components that absorb light in the wavelength range of 540 to 570 nm include metal nitride particles, red organic pigments, purple organic pigments, and blue organic pigments. Two or more of these may be contained. Among these, when a high-pressure mercury lamp is used as the exposure light source during the formation of the light-shielding layer, metal nitride particles, red organic pigments, purple organic pigments, and blue organic pigments are preferred, and when an LED lamp (365 nm) is used, metal nitride particles, red organic pigments, and purple organic pigments are preferred. It is more preferred to include metal nitride particles and purple organic pigments, which can further improve visibility after the formation of the light-shielding layer while maintaining photosensitivity when an LED lamp (365 nm) is used as the light source during the formation of the light-shielding layer.

[0028] The coloring component more preferably further contains a red organic pigment. By containing the red organic pigment, it is possible to further improve the visibility after the light-shielding layer is formed while maintaining the photosensitivity when an LED lamp (365 nm) is used as a light source during the formation of the light-shielding layer.

[0029] The thickness T1 [μm] of the light-shielding layer is preferably 0.2 to 2.0. By setting T1 [μm] to 0.2 or more, an increase in internal diffuse reflectance due to surface irregularities of the opaque wiring electrode can be further suppressed, and R1 can be easily adjusted within the above-mentioned range. On the other hand, by setting T1 [μm] to 2.0 or less, unevenness on the transparent substrate can be reduced, and the generation of bubbles due to the unevenness when laminating the transparent protective layer can be suppressed. Note that T1 can be measured using a stylus-type profilometer.

[0030] The line width of the light-shielding layer is preferably equal to the line width of the opaque wiring electrode. Therefore, the line width W [μm] of the laminated pattern is preferably 1 or more, more preferably 1.5 or more, and even more preferably 2 or more, from the viewpoint of improving conductivity. On the other hand, when the laminated pattern has the same pattern shape, the line width W [μm] of the laminated pattern is preferably 10 or less, more preferably 8 or less, from the viewpoint of further reducing the value of the internal diffuse reflectance R1 and further improving the visibility of the design. Here, the line width W of the laminated pattern can be determined by magnifying and observing the laminated pattern formation portion using an optical microscope, measuring the line width of the laminated pattern at three randomly selected locations, and calculating the average value.

[0031] Next, a method for manufacturing the wiring substrate of the present invention will be described. For example, when a laminated pattern having an opaque wiring electrode and a light-shielding layer in this order is formed on a transparent substrate, the method for manufacturing the wiring substrate of the present invention preferably includes a step of forming an opaque wiring electrode on the transparent substrate (hereinafter, sometimes referred to as an "opaque wiring electrode forming step"), and a step of forming a light-shielding layer containing a resin and a coloring component on the surface on which the opaque wiring electrode is formed to form a laminated pattern (hereinafter, sometimes referred to as a "laminate pattern forming step").

[0032] In the opaque wiring electrode forming step, examples of the method for forming the opaque wiring electrode include a method of forming a pattern by photolithography using the above-mentioned photosensitive conductive composition, a method of forming a pattern by screen printing, gravure printing, inkjet, etc. using a conductive composition, a method of forming a film of a metal, a metal composite, a composite of a metal and a metal compound, a metal alloy, etc., and forming the film by photolithography using a resist, etc. When the pattern formed from the photosensitive conductive composition exhibits conductivity by heat curing, it is preferable to heat cure at 140 to 500°C.

[0033] In the laminate pattern forming step, examples of the light-shielding layer forming step include a method of applying a positive-type photosensitive resin composition for forming a light-shielding layer according to the second embodiment of the present invention described below onto an opaque wiring electrode, and then exposing the positive-type photosensitive resin composition coating film for forming a light-shielding layer from the side opposite the coated side using the opaque wiring electrode as a mask, and developing the film to pattern the positive-type photosensitive resin composition for forming a light-shielding layer; and a method of transferring a light-shielding layer onto an opaque wiring electrode using a light-shielding layer transfer film of the present invention described below, and then exposing the light-shielding layer from the side opposite the transferred side using the opaque wiring electrode as a mask, and developing the light-shielding layer to pattern the light-shielding layer. Among these, the latter method using a light-shielding layer transfer film is preferred. By using a light-shielding layer transfer film to transfer a light-shielding layer that maintains its shape, leveling of the light-shielding layer during film formation can be prevented, which can increase the film thickness of the non-opaque wiring electrode-forming portion and increase the required exposure dose and development time. By patterning the light-shielding layer on the opaque wiring electrode using these methods, a laminate pattern can be formed.

[0034] Examples of exposure light sources include mercury lamps, halogen lamps, xenon lamps, LED lamps (365 nm, 405 nm), semiconductor lasers, KrF or ArF excimer lasers, etc. Among these, the i-line (wavelength 365 nm) of a mercury lamp and LED lamps (365 nm, 405 nm) are preferred, and LED lamps (365 nm) are more preferred due to their high output. The exposure light may be irradiated while the substrate is left stationary, or may be irradiated while transporting the substrate over the light source in a direction in which the exposure light is irradiated onto the surface opposite the surface on which the light-shielding layer is formed.

[0035] The developer used for development is preferably one that does not inhibit the conductivity of the electrode pattern, and is preferably an alkaline developer. Examples of alkaline developers include those exemplified as developers in International Publication No. 2018 / 168325. Examples of development methods include spraying the developer onto the surface of the resin layer while the substrate is left standing or rotating, immersing the resin layer in the developer, and applying ultrasonic waves while immersing the resin layer in the developer.

[0036] The light-shielding layer pattern obtained by development may be subjected to a rinse treatment with a rinse liquid. Examples of the rinse liquid include those exemplified as rinse liquids in WO 2018 / 168325.

[0037] The obtained wiring substrate may be further heated at 100 to 300°C. Heating increases the hardness of the resin layer, suppresses chipping or peeling due to contact with other members, and further improves adhesion to the substrate and wiring. Examples of heating methods include heating with an oven, an inert oven, or a hot plate, and heating with electromagnetic waves such as an infrared heater.

[0038] Next, as a second aspect of the present invention, a positive photosensitive resin composition for forming a light-shielding layer will be described. The positive photosensitive resin composition for forming a light-shielding layer of the present invention can be preferably used to form a light-shielding layer in the wiring substrate of the first aspect of the present invention described above, and by forming a light-shielding layer from such a positive photosensitive resin composition for forming a light-shielding layer, the average value R1 of the internal diffuse reflectance can be easily adjusted to fall within the aforementioned range.

[0039] The positive-type photosensitive resin composition for forming a light-shielding layer of the present invention contains (a) an alkali-soluble resin, (b) a quinone diazide compound, (c) metal nitride particles, and (d) a purple organic pigment. Here, the positive-type photosensitivity refers to a property in which the irradiated area dissolves in a developer and the unirradiated area does not dissolve in the developer.

[0040] Examples of the (a) alkali-soluble resin include those exemplified for the light-shielding layer in the wiring substrate of the first embodiment of the present invention. The (a) alkali-soluble resin is preferably a resin having a phenolic hydroxyl group, and hydrogen bonding between the phenolic hydroxyl group and the (b) quinone diazide compound can further suppress the occurrence of film loss and peeling during development in unexposed areas, making the opaque wiring electrode pattern less visible. Examples of the resin having a phenolic hydroxyl group include those described for the light-shielding layer in the wiring substrate of the first embodiment of the present invention. The content of the (a) alkali-soluble resin in the solid content of the positive photosensitive resin composition for forming a light-shielding layer is preferably 45 to 65 mass%.

[0041] Examples of the (b) quinone diazide compound include those exemplified as quinone diazide compounds contained in the positive photosensitive composition in WO 2018 / 168325. The content of the quinone diazide compound in the solid content of the positive photosensitive resin composition is preferably 5 to 25 mass%.

[0042] The positive photosensitive resin composition for forming a light-shielding layer of the present invention contains (c) metal nitride particles and (d) a violet organic pigment that absorb light in the wavelength range of 540 to 570 nm, where visibility is high, and also absorbs visible light in the wavelength range of 570 to 640 nm, thereby enabling the light-shielding layer to maintain its photosensitivity when an LED lamp (365 nm) is used as the light source during formation, while further improving the visibility of the design after formation of the light-shielding layer. Examples of the (c) metal nitride particles and (d) violet organic pigment include those described for the light-shielding layer in the wiring substrate of the first aspect of the present invention.

[0043] The content of the (c) metal nitride particles in the solid content of the positive photosensitive resin composition for forming a light-shielding layer is preferably 2.0% by volume or more, more preferably 2.5% by volume or more, from the viewpoint of further improving the visibility of the design, while the content of the metal nitride particles is preferably 6.0% by volume or less, more preferably 5.0% by volume or less, from the viewpoint of photosensitivity.

[0044] The content of the purple organic pigment (d) in the solid content of the positive photosensitive resin composition for forming a light-shielding layer is preferably 1.0% by volume or more from the viewpoint of further improving the visibility of the design, while the content of the purple organic pigment (d) is preferably 8.0% by volume or less from the viewpoint of photosensitivity.

[0045] The positive photosensitive resin composition for forming a light-shielding layer of the present invention preferably further contains (e) a red organic pigment, which absorbs light in the wavelength range of 460 to 540 nm and also absorbs visible light in the wavelength range of 570 to 640 nm, and therefore can further improve the design visibility of the light-shielding layer while maintaining the photosensitivity when an LED lamp (365 nm) is used as the light source during the formation of the light-shielding layer.

[0046] When the positive photosensitive resin composition for forming a light-shielding layer of the present invention contains (e) a red organic pigment, the total content of (c) the metal nitride particles, (d) the purple organic pigment, and (e) the red organic pigment in the solid content of the positive photosensitive resin composition is preferably 5.0% by volume or more from the viewpoint of setting the diffuse reflection per unit area within the above-mentioned preferred range and further improving visibility, while the total content thereof is preferably 15.0% by volume or less from the viewpoint of photosensitivity.

[0047] The positive-type photosensitive resin composition for forming a light-shielding layer of the present invention may contain, as necessary, a monomer having an unsaturated double bond, a photopolymerization initiator, a photoacid generator, a thermal acid generator, a sensitizer, an adhesion improver, a surfactant, a thermosetting agent, a polymerization inhibitor, a rust inhibitor, a softener, a leveling agent, and the like.

[0048] The positive photosensitive resin composition for forming a light-shielding layer of the present invention can be obtained, for example, by mixing (a) an alkali-soluble resin, (b) a quinone diazide compound, (c) metal nitride particles, (d) a purple organic pigment, and, if necessary, other additives, and then dispersing the mixture using a disperser or kneader, such as a jet mill, a bead mill, a ball mill, or a planetary ball mill.

[0049] The positive photosensitive resin composition for forming a light-shielding layer of the present invention can be preferably used in the light-shielding layer transfer film of the present invention, and such a light-shielding layer transfer film can be preferably used for forming a light-shielding layer in the wiring substrate of the first aspect of the present invention described above.

[0050] The light-shielding layer transfer film of the present invention has a light-shielding layer formed from the positive photosensitive resin composition for forming a light-shielding layer according to the second embodiment of the present invention on a release film.

[0051] The release film is preferably a film having a release layer on the surface.

[0052] Examples of release agents that form the release layer include non-silicone release agents and silicone release agents. Examples of non-silicone release agents include long-chain alkyl and fluorine-based release agents. Two or more of these may be used. Among these, non-silicone release agents are preferred because, even if release agent transfer occurs during transfer, they are less likely to cause phenomena such as developer repellency in subsequent processes, particularly the development process, and can form fine patterns while suppressing in-plane unevenness. The thickness of the release layer is preferably 50 nm or more from the viewpoint of suppressing transfer unevenness during transfer. On the other hand, the thickness of the release layer is preferably 500 nm or less from the viewpoint of suppressing release agent transfer during transfer.

[0053] The peeling strength of the release film is preferably 500 mN / 20 mm or more from the viewpoint of suppressing repelling during the formation of the light-shielding layer. On the other hand, the peeling strength of the release film is preferably 5,000 mN / 20 mm or less from the viewpoint of widening the process margin during the transfer of the light-shielding layer. Here, the peeling strength of the release film refers to the peeling strength measured when an acrylic adhesive tape "31B" manufactured by Nitto Denko Corporation is applied to the surface on which the release layer is formed using a 2 kg roller, allowed to stand for 30 minutes, and then peeled at a peel angle of 180° and a peeling speed of 0.3 m / min.

[0054] Examples of films used for the release film include films containing resins such as polyethylene terephthalate (PET), cycloolefin polymer, polycarbonate, polyimide, aramid, fluororesin, acrylic resin, and polyurethane resin. Two or more of these may be used. Among these, those that are transparent to the exposure light used in the above-mentioned laminate pattern forming process are preferred, and films containing PET, cycloolefin polymer, and polycarbonate are preferred. By selecting a film that is transparent to the exposure light, exposure can be performed through the release film in the above-mentioned laminate pattern forming process, and by placing the release film between the light-shielding layer and the photomask, contamination of the photomask can be suppressed.

[0055] The thickness of the release film is preferably 5 μm or more, more preferably 10 μm or more, from the viewpoint of improving transport stability during the formation of the light-shielding layer and suppressing unevenness in the thickness of the light-shielding layer, while the thickness of the release film is preferably 300 μm or less, more preferably 200 μm or less, from the viewpoint of ease of handling during peeling.

[0056] The thickness T1' [μm] of the light-shielding layer of the light-shielding layer transfer film is preferably 0.3 or more, more preferably 0.5 or more, from the viewpoint of making the opaque wiring electrode less visible. On the other hand, the thickness T1' [μm] of the light-shielding layer is preferably 2.0 or less, from the viewpoint of reducing the development time and further improving processability. Note that T1' can be measured using a stylus-type step gauge. Furthermore, when the light-shielding layer is transferred to form a light-shielding layer on a wiring substrate, the thickness T1' of the light-shielding layer corresponds to the thickness T1 of the light-shielding layer, but may vary depending on the method of forming the light-shielding layer.

[0057] The light-shielding layer transfer film of the present invention can be obtained, for example, by applying a positive-type photosensitive resin composition for forming a light-shielding layer onto a release film.

[0058] Examples of methods for applying the positive photosensitive resin composition for forming a light-shielding layer onto a release film include spin coating using a spinner, spray coating, roll coating, screen printing, or coating using a slit coater, blade coater, die coater, calendar coater, meniscus coater, or bar coater. The coating thickness of the positive photosensitive resin composition for forming a light-shielding layer is preferably set so that the thickness T1 of the light-shielding layer falls within the above-mentioned preferred range.

[0059] When the positive photosensitive resin composition for forming a light-shielding layer contains a solvent, it is preferably dried by heating. The drying temperature is preferably 60 to 120°C, and the drying time is preferably 1 to 20 minutes. Examples of the heating and drying device are preferably an oven, a hot plate, etc.

[0060] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. The materials used in each example are as follows.

[0061] [(a) Alkali-soluble resin] Phenol novolak resin WR-104 (manufactured by DIC Corporation).

[0062] [(b) Quinone Diazide Compound] (Production Example 1: Quinone Diazide Compound) Under a dry nitrogen stream, 21.22 g (0.05 mol) of α,α,-bis(4-hydroxyphenyl)-4-(4-hydroxy-α,α-dimethyldimethylbenzylethylbenzene (trade name TrisP-PA, manufactured by Honshu Chemical Industry Co., Ltd.) and 33.58 g (0.125 mol) of 5-naphthoquinone diazide sulfonyl chloride were dissolved in 450 g of 1,4-dioxane and the solution was brought to room temperature. To this solution, 15.18 g of triethylamine mixed with 50 g of 1,4-dioxane was added dropwise so that the temperature in the system did not exceed 35°C. After the dropwise addition, the mixture was stirred at 30°C for 2 hours. The triethylamine salt was filtered, and the filtrate was poured into water. Thereafter, the deposited precipitate was collected by filtration. This precipitate was dried in a vacuum dryer to obtain a quinone diazide compound.

[0063] [Coloring components] (c) Metal nitride particles: titanium nitride particles (particle diameter 17 nm) (d) Purple organic pigment: Pigment Violet 23 (particle diameter 50 nm) (e) Red organic pigment: Pigment Red 254 (particle diameter 100 nm) Blue organic pigment: Pigment Blue 15:6 (particle diameter 100 nm) Carbon black: MA100 (manufactured by Mitsubishi Chemical Corporation).

[0064] [Others] (Production Example 2: Acrylic Resin Having Carboxy Groups) 150 g of diethylene glycol monoethyl ether acetate (hereinafter, "DMEA") was charged into a reaction vessel under a nitrogen atmosphere and heated to 80°C using an oil bath. To this was added dropwise a mixture of 20 g of ethyl acrylate (hereinafter, "EA"), 40 g of 2-ethylhexyl methacrylate (hereinafter, "2-EHMA"), 20 g of styrene (hereinafter, "St"), 15 g of acrylic acid (hereinafter, "AA"), 0.8 g of 2,2'-azobisisobutyronitrile, and 10 g of DMEA over 1 hour. After the dropwise addition was completed, the mixture was stirred for an additional 6 hours to carry out the polymerization reaction. Thereafter, 1 g of hydroquinone monomethyl ether was added to terminate the polymerization reaction. Subsequently, a mixture consisting of 5 g of glycidyl methacrylate (hereinafter referred to as "GMA"), 1 g of triethylbenzylammonium chloride, and 10 g of DMEA was added dropwise over 0.5 hours. After the completion of the dropwise addition, the mixture was stirred for an additional 2 hours to carry out the addition reaction. The resulting reaction solution was purified with methanol to remove unreacted impurities, and then vacuum dried for 24 hours to obtain an acrylic resin having carboxy groups with a copolymerization ratio (by mass): EA / 2-EHMA / St / GMA / AA = 20 / 40 / 20 / 5 / 15. The acid value of the resulting acrylic resin having carboxy groups was measured in accordance with JIS K 0070 (1992) and found to be 103 mgKOH / g. The weight-average molecular weight of the resulting acrylic resin having carboxy groups was 17,000.

[0065] (Production Example 3: Acrylic Resin Having Phenolic Hydroxyl Groups and Carboxy Groups) 150 g of 2-methoxy-1-methylethyl acetate (hereinafter "PMA") was charged into a reaction vessel under a nitrogen atmosphere and heated to 80°C using an oil bath. To this was added dropwise a mixture consisting of 20 g of EA, 20 g of 2-EHMA, 20 g of 4-hydroxystyrene (hereinafter "HS"), 15 g of N-methylolacrylamide (hereinafter "MAA"), 25 g of AA, 0.8 g of 2,2'-azobisisobutyronitrile, and 10 g of PMA over 1 hour. After completion of the dropwise addition, the mixture was heated and stirred at 80°C for an additional 6 hours to carry out a polymerization reaction. Thereafter, 1 g of hydroquinone monomethyl ether was added to terminate the polymerization reaction. The resulting reaction solution was purified with methanol to remove unreacted impurities, and then vacuum dried for 24 hours to obtain an acrylic resin having phenolic hydroxyl groups and carboxy groups with a copolymerization ratio (by mass): EA / 2-EHMA / HS / MAA / AA=20 / 20 / 20 / 15 / 25. The acid value was measured in the same manner as in Production Example 2 and was found to be 153 mgKOH / g. The weight-average molecular weight of the resulting acrylic resin having phenolic hydroxyl groups and carboxy groups was 10,000.

[0066] (Production Example 4: Photosensitive conductive paste) Into a 100 mL clean bottle were placed 3.0 g of the acrylic resin having a carboxy group obtained in Production Example 2, 0.3 g of a photopolymerization initiator N-1919 (manufactured by ADEK Corporation), 1.2 g of the monomer "Light Acrylate" (registered trademark) BP-4EA, 0.5 g of a dispersant "BYK (registered trademark)"-LP21116 (manufactured by BYK-Chemie), 79.0 g of propylene glycol monomethyl ether acetate (hereinafter referred to as "PGMEA"), and 16.0 g of silver fine particles (manufactured by Nisshin Engineering Inc.) having an average surface carbon coating layer thickness of 1 nm and a particle diameter of 40 nm, and mixed using "Awatori Rentaro (registered trademark)" ARE-310 (manufactured by Thinky Corporation) to obtain 100.0 g of a photosensitive conductive paste. The viscosity of the obtained photosensitive conductive paste was measured using an E-type viscometer at a temperature of 25° C. and a rotation speed of 100 rpm, and was found to be 3 mPa·s.

[0067] (Production Example 5: Photosensitive insulating paste) 15.5 g of the acrylic resin having a carboxy group obtained in Production Example 2, 5.2 g of "Light Acrylate (registered trademark)" BP-4EAL, 0.3 g of photopolymerization initiator N-1919, and 79.0 g of PGMEA were placed in a 100 mL clean bottle and mixed using a rotation-revolution vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 to obtain 100.0 g of photosensitive insulating paste. The obtained photosensitive insulating paste was applied to a 4-inch silicone wafer, and the refractive index at a wavelength of 550 nm was measured using a prism coupler (manufactured by Metricon, PC-2000) at room temperature of 23°C, resulting in a value of 1.53.

[0068] The evaluations in each of the examples and comparative examples were carried out by the following methods.

[0069] (1) Line Width W of Laminate Pattern For the substrate after the formation of the laminate pattern obtained in each Example and Comparative Example, the laminate pattern formation portion was observed under magnification using an optical microscope, and the line width of the laminate pattern was measured at three randomly selected locations, and the average value was taken as the line width W of the laminate pattern.

[0070] (2) Internal Diffuse Reflectance An anti-reflection film with an adhesive layer, MTAR-3 (manufactured by Mitate Imaging Co., Ltd.), was attached with a rubber roller to the transparent protective layer-formed surface of the wiring substrate obtained in each example and comparative example. Furthermore, an adhesive black PET film, Kakukiri Miel (manufactured by Tomoegawa Paper Co., Ltd.), was attached with a rubber roller to the laminated pattern-non-forming surface of the wiring substrate, to prepare the internal diffuse reflectance evaluation substrate 16 shown in FIG. 3. Using a spectrophotometer (CM-2500d) manufactured by Konica Minolta Sensing Co., Ltd., the diffuse reflectance SCE at wavelengths of 540, 550, 560, and 570 nm of the laminated pattern-forming portion of the internal diffuse reflectance evaluation substrate was measured, and the average value was taken as the average internal reflectance R1. Next, the diffuse reflectance SCE was measured at wavelengths of 540, 550, 560, and 570 nm of the laminate pattern non-forming portion of the substrate for internal diffuse reflectance evaluation using a spectrophotometer (CM-2500d) manufactured by Konica Minolta Sensing Co., Ltd., and the average value was taken as the average internal reflectance R2.

[0071] (3) Difficulty in Visibility For the wiring substrates obtained in each Example and Comparative Example, a black sheet SuperBlackIR (manufactured by Systems Engineering Co., Ltd.) was placed on the side opposite to the side on which the opaque wiring electrode was formed, and then light was projected onto the side on which the opaque wiring electrode was formed using a floodlight. Ten people each visually inspected the surface from a distance of 30 cm, and the difficulty in visibility was evaluated based on the number of people who could see the mesh-shaped opaque wiring electrode.

[0072] (4) Design visibility In each example and comparative example, a light projector was used to project light onto the anti-reflection film-attached surface of the substrate for evaluating internal diffuse reflectance prepared in (2) Internal Diffuse Reflectance. Ten people visually inspected the surface from a distance of 100 cm, and the design visibility was evaluated based on the number of people who could clearly see the boundary between the laminate pattern forming portion 10 and the laminate pattern non-forming portion 11.

[0073] (5) Photosensitivity In each example and comparative example, the exposure device in <Formation of light-shielding layer> was replaced with a 365 nm LED lamp (manufactured by CCS Inc.), and the exposure was 500 mJ / cm ２ , 800 mJ / cm ２ , 1500mJ / cm ２ , 3000mJ / cm ２ The minimum exposure amount at which the exposed area dissolves in the developer within 30 seconds was defined as the required exposure amount, and the photosensitivity was evaluated. ２ If the sample did not dissolve within 30 seconds, it was evaluated as 3000 or less.

[0074] Example 1 <Opaque Wiring Electrode Formation Step> The photosensitive conductive paste (D-1) obtained in Production Example 4 was applied by spin coating to one surface of alkali-free glass "AN Wizus (registered trademark)" (manufactured by AGC Corporation, transmittance at a wavelength of 365 nm: 91%, transmittance at a wavelength of 550 nm: 92%) so as to have a thickness of 1 μm after drying, and dried at 90° C. for 8 minutes. Using an exposure mask having a mesh-shaped laminated pattern forming portion 10 and a laminated pattern non-forming portion 11 shown in FIG. 4, an exposure amount of 150 mJ / cm was applied using an exposure device (PEM-6M; manufactured by Union Optical Co., Ltd.). ２The mask was exposed to light at a wavelength of 365 nm (equivalent to a wavelength of 365 nm). The mesh-shaped pattern shown in FIG. 5 had a mesh pitch 14 of 400 μm and a mesh angle 15 of 58°. It was a negative pattern having a 4 μm opening width laminated pattern portion (mask opening) 12 and a non-laminated pattern portion (mask light-shielding portion) 13. Note that the image in FIG. 5 is inverted in black and white for ease of illustration. The mask was then developed using a 0.1% by mass aqueous solution of tetramethylammonium hydroxide as a developer for twice the time it took for the exposed portion to dissolve. The mask was then rinsed with ultrapure water for 30 seconds, and then heated and cured in a box oven at 220°C for 60 minutes to form an opaque wiring electrode. The thickness of the opaque wiring electrode was measured using a stylus-type step profiler "Surfcom (registered trademark)" 1400 (manufactured by Tokyo Seimitsu Co., Ltd.) and found to be 0.5 μm.

[0075] <Layer Pattern Forming Step> (Preparation of Positive Photosensitive Resin Composition for Forming Light-Shielding Layer) Into a 100 mL clean bottle were placed (a) 2.89 g of ferronovolac resin WR-104 (manufactured by DIC Corporation) as an alkali-soluble resin, (b) 0.49 g of the quinone diazide compound obtained in Production Example 1 as a quinone diazide compound, 0.22 g of carboxybenzotriazole "VERZONE (registered trademark)" C-BTA (manufactured by Daiwa Chemical Industry Co., Ltd.), 0.01 g of leveling agent "BYK (registered trademark)"-331 (manufactured by BYK-Chemie), and 44.45 g of PGMEA, and the mixture was mixed using a rotation-revolution vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 (manufactured by Thinky Corporation) to obtain 48.07 g of a resin solution. The obtained 48.07 g of resin solution, 1.21 g of carbon black MA100 (manufactured by Mitsubishi Chemical Corporation), and 0.72 g of dispersant "BYK"-LP21116 (manufactured by BYK-Chemie) were mixed and kneaded using an Ultra Apex Mill (manufactured by Kotobuki Industries Co., Ltd.) equipped with a centrifugal separator filled with 70% by volume of 0.10 mmφ zirconia beads (manufactured by Toray Industries, Inc.), to obtain 50.0 g of a positive photosensitive resin composition 1 for forming a light-shielding layer.

[0076] (Formation of Light-Shielding Layer) The obtained positive photosensitive resin composition 1 for forming a light-shielding layer was spin-coated on the surface of the opaque wiring electrode formed in the <Opaque wiring electrode forming step> so that the film thickness after drying would be 1.4 μm, and then dried at 100° C. for 10 minutes. Thereafter, using the opaque wiring electrode as a mask, an exposure device (PEM-6M) was used to apply light from the side opposite the surface on which the opaque wiring electrode was formed at an exposure dose (equivalent to a wavelength of 365 nm) of 10,000 mJ / cm ２ The film was then developed using a 2.38% by mass aqueous solution of tetramethylammonium hydroxide as a developer until the transparent substrate in the exposed area was exposed, forming a light-shielding layer pattern on the opaque wiring electrode, thereby forming a laminated pattern. The film was then heated in a box oven at 220°C for 60 minutes.

[0077] <Transparent Protective Layer Formation Step> The photosensitive insulating paste obtained in (Production Example 5) was spin-coated onto the substrate with the laminated pattern obtained in the <Laminated Pattern Formation Step> so that the film thickness after drying would be 3.0 μm, and then dried at 80° C. for 5 minutes. Using an exposure device (PEM-6M), the applied surface was exposed to an exposure dose (equivalent to a wavelength of 365 nm) of 100 mJ / cm. ２ The exposed film was then developed for 60 seconds using a 0.1% by mass aqueous solution of tetramethylammonium hydroxide as a developer. The exposed film was then heated in a box oven at 220° C. for 60 minutes to obtain a wiring substrate having a transparent protective layer formed thereon.

[0078] (Example 2) A wiring substrate was obtained in the same manner as (Example 1), except that the mesh pitch and occupancy rate S of the exposure mask in the <opaque wiring electrode formation step> and the composition in (preparation of positive photosensitive resin composition for forming light-shielding layer) were changed as shown in Table 1.

[0079] (Examples 3 to 9) Wiring substrates were obtained in the same manner as (Example 2), except that the composition in (Preparation of positive photosensitive resin composition for forming light-shielding layer) and the exposure dose in (Formation of light-shielding layer) were changed as shown in Tables 1 and 2.

[0080] Comparative Example 1 A wiring substrate was obtained in the same manner as in Example 3, except that the formation of the light-shielding layer was not carried out.

[0081] (Comparative Examples 2 to 6) Wiring substrates were obtained in the same manner as (Example 2), except that the composition in (Preparation of positive photosensitive resin composition for forming light-shielding layer) and the exposure dose in (Formation of light-shielding layer) were changed as shown in Table 3.

[0082] Example 10 <Formation of Opaque Wiring Electrode> In the same manner as in Example 2, a substrate with an opaque wiring electrode was obtained.

[0083] <Layer Pattern Forming Step> (Preparation of Positive Photosensitive Resin Composition for Forming Light-Shielding Layer) Into a 100 mL clean bottle were placed 0.77 g of phenol novolak resin WR-104 (manufactured by DIC Corporation), 2.33 g of the acrylic resin having a phenolic hydroxyl group and a carboxy group obtained in Production Example 2, 0.77 g of the quinone diazide compound obtained in Production Example 1, 0.19 g of carboxybenzotriazole "VERZONE (registered trademark)" C-BTA (manufactured by Daiwa Chemical Industry Co., Ltd.), 0.01 g of leveling agent "BYK (registered trademark)"-331 (manufactured by BYK-Chemie), and 44.28 g of PGMEA, and the mixture was mixed using a rotation-revolution vacuum mixer "Awatori Rentaro (registered trademark)" ARE-310 (manufactured by Thinky Corporation) to obtain 48.77 g of a resin solution. The obtained 48.77 g of resin solution, 0.79 g of titanium nitride particles, 0.32 g of purple organic pigment, 0.11 g of red organic pigment, and 0.50 g of dispersant "BYK (registered trademark)"-LP21116 (manufactured by BYK-Chemie K.K.) were mixed together and kneaded using an Ultra Apex Mill (manufactured by Kotobuki Industries Co., Ltd.) equipped with a centrifugal separator filled with 70% by volume of 0.10 mmφ zirconia beads (manufactured by Toray Industries, Inc.), thereby obtaining 50.0 g of a positive photosensitive resin composition 2 for forming a light-shielding layer.

[0084] (Preparation of Light-Shielding Layer Transfer Film) A non-silicone release agent AL-5 (manufactured by Lintec Corporation) was applied to one side of a PET film "Lumirror (registered trademark)" FB40 (manufactured by Toray Industries, Inc.) (thickness: 16 μm), followed by heat treatment and drying to form a release layer having a thickness of 100 nm on the surface of the substrate, thereby obtaining a release film. For the obtained release film, an acrylic adhesive tape "31B" manufactured by Nitto Denko Corporation was attached to the surface on which the release layer was formed using a 2 kg roller, and after leaving it to stand for 30 minutes, the peel force when peeled under conditions of a peel angle of 180° and a peel speed of 0.3 m / min was measured and found to be 1,480 mN / 20 mm.

[0085] The obtained positive photosensitive resin composition 2 for forming a light-shielding layer was applied to the release layer surface of the obtained release film using a coater so that the thickness T1' after drying would be 1.4 μm, and the coating was dried at 80° C. for 4 minutes to form a light-shielding layer, thereby obtaining a light-shielding layer transfer film.

[0086] (Formation of Light-Shielding Layer) The light-shielding layer transfer film obtained in <Preparation of Light-Shielding Layer Transfer Film> was thermocompressed onto the opaque wiring electrode formed in the <Opaque Wiring Electrode Formation Step> at 80°C and at a speed of 0.1 m / min so that the light-shielding layer of the light-shielding layer transfer film was in contact with the opaque wiring electrode formed in the <Opaque Wiring Electrode Formation Step>, and the release film was peeled off. Thereafter, using an exposure device (PEM-6M), the opaque wiring electrode was used as a mask to expose the opaque wiring electrode from the side opposite the surface on which the opaque wiring electrode was formed with an exposure dose (equivalent to a wavelength of 365 nm) of 100 mJ / cm. ２ The film was then developed using a 1.00% by mass aqueous solution of sodium carbonate as a developer until the transparent substrate in the exposed area was exposed, forming a light-shielding layer pattern on the opaque wiring electrode, thereby forming a laminated pattern. The film was then heated in a box oven at 220°C for 60 minutes.

[0087] <Formation of Transparent Protective Layer> A transparent protective layer was formed in the same manner as in Example 1 to obtain a wiring substrate.

[0088] The main configurations and evaluation results of each of the examples and comparative examples are shown in Tables 1 to 4.

[0089]

[0090]

[0091]

[0092]

[0093] 1: Transparent substrate 2: Opaque wiring electrode 3: Light-shielding layer 4: Wiring substrate 5: Laminated pattern 6: Transparent protective layer 7: Adhesive layer 8: Anti-reflection film 9: Black film 10: Laminated pattern formed portion 11: Laminated pattern not formed portion 12: Laminated pattern portion (mask opening) 13: Non-laminated pattern portion (mask light-shielding portion) 14: Mesh pitch 15: Mesh angle 16: Substrate for evaluating internal diffuse reflectance

Claims

1. A wiring substrate having a laminated pattern of an opaque wiring electrode and a light-shielding layer containing a resin and a coloring component on a transparent substrate, wherein the average value R1 of the internal diffuse reflectance at a wavelength of 540 to 570 nm measured from the light-shielding layer side of the laminated pattern forming portion is 0.03 to 0.11%, The wiring substrate in which the average internal diffuse reflectance R1 [%], the average internal diffuse reflectance R2 [%] at a wavelength of 540 to 570 nm of the laminate pattern non-forming portion, the line width W [μm] of the laminate pattern, and the ratio S of the laminate pattern area to the area of ​​the laminate pattern forming portion (laminated pattern area / area of ​​laminate pattern forming portion) satisfy the relationship of the following formula (1). 0.0≦((R1×W)-(R2×(1-S))) / S≦7.0 (1)

2. 2. The wiring substrate according to claim 1, wherein the thickness T1 [μm] of the light-shielding layer is 0.2 to 2.0 μm.

3. (a) an alkali-soluble resin, (b) a quinone diazide compound, (c) metal nitride particles, and (d) a purple organic pigment; The positive photosensitive resin composition for forming a light-shielding layer contains the metal nitride particles (c) in an amount of 2.0 to 6.0% by volume.

4. The positive photosensitive resin composition for forming a light-shielding layer according to claim 3, further comprising (e) a red organic pigment.

5. 5. The positive photosensitive resin composition for forming a light-shielding layer according to claim 4, wherein the total content of (c) the metal nitride particles, (d) the purple organic pigment, and (e) the red organic pigment is 5.0 to 15.0% by volume.

6. A light-shielding layer transfer film having a light-shielding layer formed from the positive photosensitive resin composition for forming a light-shielding layer according to claim 3 on a release film.

7. 7. The light-shielding layer transfer film according to claim 6, wherein the thickness T1' [μm] of the light-shielding layer is 0.3 to 2.0 μm.

8. 2. The method for manufacturing a wiring substrate according to claim 1, forming an opaque wiring electrode on a transparent substrate; a step of applying the positive photosensitive resin composition for forming a light-shielding layer according to claim 3 to the surface on which the opaque wiring electrode is formed; and a step of exposing the photosensitive resin composition coating film from the side opposite to the coating side using the opaque wiring electrode as a mask and developing the same to pattern the photosensitive resin composition coating film, thereby forming a laminated pattern of the opaque wiring electrode and the light-shielding layer; A method for manufacturing a wiring substrate having the above structure.

9. 2. The method for manufacturing a wiring substrate according to claim 1, forming an opaque wiring electrode on a transparent substrate; A step of transferring the light-shielding layer of the light-shielding layer transfer film according to claim 6 onto the surface on which the opaque wiring electrode is formed; and a step of exposing the light-shielding layer from the surface opposite to the transfer surface using the opaque wiring electrode as a mask and developing the light-shielding layer to pattern the light-shielding layer, thereby forming a laminated pattern of the opaque wiring electrode and the light-shielding layer; A method for manufacturing a wiring substrate having the above structure.