TWI674043B - Printed wiring board - Google Patents

Abstract

An object of the present invention is to provide a thin printed wiring board capable of suppressing warpage during a component mounting step.

The solution of the present invention is a printed wiring board, which is a printed wiring board including first and second solder resist layers, wherein the thickness of the first solder resist layer is t ₁ (μm), and the elastic modulus after hardening ( 23 ° C) is G ₁ (GPa), the thickness of the second solder resist layer is t ₂ (μm), the elastic modulus after hardening (23 ° C) is G ₂ (GPa), and the thickness of the printed wiring board is Z (μm), satisfy the following conditions (1) to (3), G ₁ is 6 or more, (1) Z ≦ 250; (2) (t ₁ + t ₂ ) /Z≧0.1; and (3) G ₁ × [t ₁ / (t ₁ + t ₂ )] + G ₂ × [t ₂ / (t ₁ + t ₂ )] ≧ 6.

Description

Printed wiring board

The present invention relates to a printed wiring board.

The outermost layer of the printed wiring board is usually provided with a solder resist layer as a protection during the mounting step of the semiconductor wafer (hereinafter also referred to as a "part") in order to prevent the solder from adhering to the part that does not need to be attached and at the same time to prevent corrosion of the circuit board membrane. The solder resist layer is generally formed by providing a layer of a photocurable resin composition on a circuit board and exposing / developing the layer (for example, Patent Document 1).

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2009-258613

In recent years, with the replacement of lead-free solder with lead-free solder, solder reflow temperature has increased during the component mounting step. In recent years, in order to The miniaturization of electronic equipment has been achieved, and the thickness of printed wiring boards has been further reduced.

As the thickness of printed wiring boards has progressed, the inventors have found that during the mounting process of the parts, the printed wiring boards may warp, and problems such as circuit distortion or poor contact of the parts may occur.

The subject of the present invention is to provide a thin printed wiring board, which is capable of suppressing warpage in a component mounting step.

The present inventors have continually devoted themselves to reviewing the above-mentioned problems and found that by combining two solder resist layers having a specific thickness and elastic modulus, the above problems can be solved, and the present invention has been completed.

That is, the present invention includes the following.

[1] A printed wiring board, which is a printed wiring board including first and second solder resist layers, wherein the thickness of the first solder resist layer is t ₁ (μm), and the elastic modulus after curing (23 ° C) is When G ₁ (GPa), the thickness of the second solder resist layer is t ₂ (μm), the elastic modulus (23 ° C) after hardening is G ₂ (GPa), and the thickness of the printed wiring board is Z (μm) , Satisfy the following conditions (1) ~ (3): (1) Z ≦ 250; (2) (t ₁ + t ₂ ) /Z≧0.1; and (3) G ₁ × [t ₁ / (t ₁ + t ₂ )] + G ₂ × [t ₂ / (t ₁ + t ₂ )] ≧ 6, and G ₁ is 6 or more.

[2] The printed wiring board according to [1], wherein the glass transition temperature (Tg) after the first solder resist layer is cured is 150 ° C or higher.

[3] The printed wiring board according to [1] or [2], wherein the first solder resist layer is formed by curing a resin composition having an inorganic filler content of 60% by mass or more.

[4] The printed wiring board according to any one of [1] to [3], wherein the condition (2) is 0.1 ≦ (t ₁ + t ₂ ) /Z≦0.5.

[5] The printed wiring board according to any one of [1] to [4], wherein G ₂ is 6 or more.

[6] The printed wiring board according to any one of [1] to [5], wherein the elastic modulus (200 ° C) of the first solder resist layer after hardening is G ₁ ′ (GPa), and the second resistance When the elastic modulus (200 ° C) of the flux layer after hardening is G ₂ ′ (GPa), the following condition (4) is further satisfied: (4) G ₁ ′ × [t ₁ / (t ₁ + t ₂ )] + G ₂ '× [t ₂ / (t ₁ + t ₂ )] ≧ 0.2.

[7] A semiconductor device including the printed wiring board according to any one of [1] to [6].

[8] A resin sheet group, which is a resin sheet group for a solder resist layer of a printed wiring board, and includes a first resin composition layer having a first support and a first resin composition layer bonded to the first support. A resin sheet, a second resin sheet having a second support, and a second resin composition layer bonded to the second support, and the thickness of the first resin composition layer is t _1p (μm), after curing, The elastic modulus (23 ° C) is G ₁ (GPa), the thickness of the second resin composition layer is t _2p (μm), the cured elastic modulus (23 ° C) is G ₂ (GPa), and printed wiring When the thickness of the plate is Z (μm), the following conditions (1 ') to (3') are satisfied: (1 ') Z ≦ 250; (2') (t _1p + t _2p ) /Z≧0.1; and ( 3 ') G ₁ × [t _1p / (t _1p + t _2p )] + G ₂ × [t _2p / (t _1p + t _2p )] ≧ 6, and G ₁ is 6 or more.

According to the present invention, it is possible to provide a thin printed wiring board which can suppress warpage in a mounting step of a part.

[Form of Implementing Invention] [Printed wiring board]

The printed wiring board of the present invention includes the first and second solder resist layers, and is characterized in that the thickness of the first solder resist layer is t ₁ (μm), and the elastic modulus (23 ° C) after hardening is G ₁ (GPa ), When the thickness of the second solder resist layer is t ₂ (μm), the elastic modulus (23 ° C) after hardening is G ₂ (GPa), and the thickness of the printed wiring board is Z (μm), the following is satisfied: Conditions (1) ~ (3): (1) Z ≦ 250; (2) (t ₁ + t ₂ ) /Z≧0.1; and (3) G ₁ × [t ₁ / (t ₁ + t ₂ )] + G ₂ × [t ₂ / (t ₁ + t ₂ )] ≧ 6, and G ₁ is 6 or more.

The printed wiring board of the present invention, which is formed by combining the first and second solder resist layers having a specific thickness and elastic modulus, can suppress warpage and suppress a circuit during a mounting step of a part using a high solder reflow temperature. Problems such as distortion or poor contact of parts occur.

-Condition (1)-

Condition (1) relates to the thickness Z (μm) of the printed wiring board of the present invention. The thickness Z of the printed wiring board means the entire thickness of the printed wiring board including the circuit board and the first and second solder resist layers provided on both sides of the circuit board. From the viewpoint of thinning, the thickness (Z) of the printed wiring board of the present invention is 250 μm or less, preferably 240 μm or less, more preferably 230 μm or less, still more preferably 220 μm or less, and still more preferably 210 μm or less, Particularly preferred are 200 μm or less, 190 μm or less, 180 μm or less, 170 μm or less, 160 μm or less, or 150 μm or less. The printed wiring board of the present invention can suppress warpage in the mounting step even when the thickness is so thin. The lower limit of the thickness (Z) is not particularly limited, and is usually 20 μm or more, or 30 μm or more.

-Condition (2)-

Condition (2) relates to the thicknesses t ₁ (μm) and t ₂ (μm) of the first and second solder resist layers included in the printed wiring board of the present invention. Here, the thicknesses t ₁ (μm) and t ₂ (μm) of the first and second solder resist layers are the thicknesses from the base surface of the circuit substrate (the portion of the surface of the circuit substrate where there is no surface circuit). From the viewpoint of suppressing warpage of the printed wiring board during the mounting step, the ratio of the thickness of the first and second solder resist layers to (t ₁ + t ₂ ) to the thickness Z of the printed wiring board is (t ₁ + t ₂ ) / Z ratio is 0.1 or more. Although it depends on the value on the right side of condition (3), it is preferably 0.15 or more, more preferably 0.2 or more, 0.22 or more, 0.24 or more, 0.26 or more, 0.28 or more, or 0.3 or more. From the viewpoint of obtaining a printed wiring board having a desired wiring density, the upper limit of the (t ₁ + t ₂ ) / Z ratio is preferably 0.5 or less, more preferably 0.45 or less, still more preferably 0.4 or less, and 0.39. Below, 0.38 or less, 0.37 or less, 0.36 or less, 0.36 or less, or 0.34 or less.

The thickness t _{1 of the} first solder resist layer is not particularly limited as long as it satisfies the specific (t ₁ + t ₂ ) / Z ratio, and is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 15 μm or more, 20 μm or more, or 25 μm or more. The upper limit of the thickness t ₁ is not particularly limited. When the specific (t ₁ + t ₂ ) / Z ratio is satisfied, the upper limit is not particularly limited. It is preferably 120 μm or less, more preferably 100 μm or less, and even more preferably 80 μm. Below, 70 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less.

The thickness t _{2 of} the second solder resist layer is not particularly limited when the specific (t ₁ + t ₂ ) / Z ratio described above is satisfied, and the thickness t _{1 of the} first solder resist layer and the thickness of the printed wiring board are considered. The thickness Z may be determined. The upper limit of the thickness t ₂ of the second solder resist layer may be generally 120 μm or less or 100 μm or less, and the lower limit of the thickness t ₂ is usually 5 μm or more or 10 μm or more.

-Condition (3)-

Condition (3) relates to the elastic modulus (23 ° C) of the first and second solder resist layers contained in the printed wiring board of the present invention after hardening. The first and second solder resist layers are formed by curing a resin composition as described later. The elastic modulus (23 ° C) after curing refers to the elastic modulus of the solder resist layer at 23 ° C after the resin composition is cured. When the elastic modulus (23 ° C) of the first and second solder resist layers after hardening are G ₁ (GPa) and G ₂ (GPa), respectively, the formula: G ₁ × [t ₁ / (t ₁ + t ₂ ) ) + G ₂ × [t ₂ / (t ₁ + t ₂ )] value (hereinafter also referred to as "average thickness increase of G ₁ and G ₂ ") to suppress warpage of the printed wiring board during the mounting step From a viewpoint, it is 6 or more, preferably 6.2 or more, more preferably 6.4 or more, even more preferably 6.6 or more, and still more preferably 6.8 or more. If the average thickness increase of G ₁ and G ₂ is 6.8 or more, and if the thickness Z of the printed wiring board is 200 μm or less, the warpage of the printed wiring board in the mounting step can be suppressed even in a thin case. The weighted average of G ₁ and G ₂ reduces the thickness of the printed wiring board and reduces the (t ₁ + t ₂ ) / Z ratio. From a warping point of view, 7 or more, 7.5 or more, 8 or more, 8.5 or more, 9 or more, 9.5 or more, 10 or more, 10.5 or more, 11 or more, 11.5 or more, 12 or more, 12.5 or more, or 13 or more . The upper limit of the thickness-weighted average values of G ₁ and G ₂ is not particularly limited, and may generally be 40 or less, 30 or less. The elastic modulus (23 ° C) after curing of the first and second solder resist layers can be measured at 23 ° C by a tensile weighting method using a tensile tester. As a tensile testing machine, for example, "RTC-1250A" manufactured by ORIENTEC is available.

The elastic modulus (23 ° C) of the first solder resist layer after hardening, that is, G ₁ (GPa) is 6 or more. The value of G ₁ is 6 or more and the average thickness increase of G ₁ and G ₂ is not particularly limited in the above-mentioned specific range. From the viewpoint of sufficiently suppressing the warpage of the printed wiring board during the mounting step, it is preferable. 6.2 or more, more preferably 6.4 or more, even more preferably 6.6 or more, and still more preferably 6.8 or more, particularly preferably 7 or more, 7.5 or more, 8 or more, 8.5 or more, 9 or more, 9.5 or more, 10 or more, 10.5 Above, 11 or more, 11.5 or more, 12 or more, 12.5 or more, or 13 or more. The upper limit of G ₁ is not particularly limited, and may generally be 40 or less, 30 or less.

The elastic modulus (23 ° C.) of the second solder resist layer after hardening, that is, G ₂ (GPa) is not particularly limited as long as the average thickness increase of G ₁ and G ₂ is within the above-mentioned specific range. For example, as long as the value G ₂ is G ₁ and G ₂ the thickness of the average increase in the specific range may be determined to be in the range of 1 to 30. From the viewpoint that it is easy to suppress the warpage of the printed wiring board in the mounting step even when the thickness Z of the printed wiring board is made small and the (t ₁ + t ₂ ) / Z ratio is lowered, the value of G ₂ Those with a score of 6 or more are particularly preferred.

From the viewpoint of further suppressing the warpage of the printed wiring board in the mounting step, the elastic modulus (200 ° C) after curing of the first and second solder resist layers is G ₁ ′ (GPa) and G ₂ When '(GPa), the following conditions (4) are satisfied: (4) G ₁ ' × [t ₁ / (t ₁ + t ₂ )] + G ₂ '× [t ₂ / (t ₁ + t ₂ )] ≧ 0.2 is preferred.

G ₁ '× (t ₁ / (t ₁ + t ₂ )] + G ₂ ' × (t ₂ / (t ₁ + t ₂ )] value (hereinafter also referred to as "thickness of G ₁ 'and G ₂ '"Aggravated average value") is more preferably 0.22 or more, and more preferably 0.24 or more. When the weighted average of G ₁ ′ and G ₂ ′ is 0.24 or more, even when the thickness Z of the printed wiring board is made thinner to 200 μm or less, warpage of the printed wiring board in the mounting step can be suppressed. The average thickness increase of G ₁ ′ and G ₂ ′ suppresses the printed wiring in the mounting step even when the thickness Z of the printed wiring board is reduced and the (t ₁ + t ₂ ) / Z ratio is lowered. From the viewpoint of warpage of the plate, 0.3 or more, 0.4 or more, 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, 0.9 or more, 1.0 or more, 1.1 or more, 1.2 or more, 1.3 or 1.3 or more are particularly preferred. The upper limit of the thickness-weighted average value of G ₁ ′ and G ₂ ′ is not particularly limited, and may generally be 15 or less, 10 or less. In addition, the so-called elastic modulus after hardening (200 ° C) refers to the elastic modulus of the solder resist layer at 200 ° C after the resin composition is cured, and can be stretched at 200 ° C by a tensile weighting method using a tensile tester. Determination.

The elastic modulus (200 ° C) of the first solder resist layer, which is G ₁ ′ (GPa), is preferably 0.2 or more from the viewpoint of sufficiently suppressing warpage of the printed wiring board in the mounting step. , 0.22 or higher is better, 0.24 or higher is better, 0.3 or higher, 0.4 or higher, 0.5 or higher, 0.6 or higher, 0.7 or higher, 0.8 or higher, 0.9 or higher, 1.0 or higher, 1.1 or higher, 1.2 or higher, 1.3 or higher or 1.4 or higher Especially good. The upper limit of G ₁ ′ is not particularly limited, and may generally be 15 or less, 10 or less.

Elastic modulus (200 ℃) after the second curing solder resist layers, i.e., G ₂ '(GPa), with G _1' relationship, the thickness of G ₁ 'and G _2' is increased as the average of lines to be above A specific range value is preferred. For example, the 'value, as long as the G _1' G ₂ and a thickness G ₂ 'is the average increase in the specific range, preferably in the line to the range of 0.1 to 10. From the viewpoint that it is easy to suppress the warpage of the printed wiring board in the mounting step even when the thickness Z of the printed wiring board is made small and the (t ₁ + t ₂ ) / Z ratio is lowered, the value of G ₂ ′ Those with 0.2 or more are particularly preferred.

In the printed wiring board of the present invention that satisfies the above conditions (1), (2), and (3), warpage can be suppressed even in a mounting step using a high solder reflow temperature. In one embodiment, the printed wiring board of the present invention can suppress warpage of the printed wiring board to 50 μm or less in a mounting step using a high solder reflow temperature with a peak temperature of 260 ° C. In the present invention, the warpage of the printed wiring board is the difference between the maximum height and the minimum height of the displacement data when the warpage behavior of the central 25mm corner of the printed wiring board is observed with a Shadow Moire device. value. During the measurement, the reflow temperature curve (curve for lead-free components; peak temperature) described in IPC / JEDEC J-STD-020C ("Moisture / Reflow Sensitivity Classification For Nonhermetic Solid State Surface Mount Devices", July 2004) was reproduced. 260 ° C, the time required for the temperature rise from 25 ° C to the peak temperature is 5 minutes) After the reflow device is inserted into the printed wiring board once, the printed wiring is heat-treated with the reflow temperature curve based on the above IPC / JEDEC J-STD-020C as a guide The displacement data was obtained on one side of the board and the grid lines provided on the other side of the printed wiring board. In addition, the reflow device may be, for example, "HAS-6116" manufactured by ANTU Japan, and the shadow moire device may be, for example, "TherMoire AXP" manufactured by Akrometrix. By making the value on the right in the condition (3) the above-mentioned preferred value, even if the thickness Z of the printed wiring board is made small and the (t ₁ + t ₂ ) / Z ratio is made lower, the mounting can be made. In the step, the warpage of the printed wiring board is suppressed to 48 μm or less, 46 μm or less, 44 μm or less, 42 μm or less, or 40 μm or less.

[Resin sheet group for solder resist layer of printed wiring board]

The printed wiring board of the present invention can be manufactured by providing first and second solder resist layers having a specific thickness and elastic modulus on both sides of a circuit board.

Hereinafter, a group of resin sheets ("resin sheet group") which can be used when manufacturing the printed wiring board of this invention is demonstrated.

The resin sheet group for a solder resist layer of a printed wiring board of the present invention is characterized by including a first resin sheet having a first support and a first resin composition layer bonded to the first support, and a first resin sheet 2 support and a second resin sheet formed of a second resin composition layer bonded to the second support, and the thickness of the first resin composition layer is t _1p (μm), and the elastic modulus after curing (23 ℃) is G ₁ (GPa), the thickness of the second resin composition layer is t _2p (μm), the elastic modulus after curing (23 ° C.) is G ₂ (GPa), and the thickness of the printed wiring board is Z (μm), the following conditions (1 ') ~ (3') are satisfied: (1 ') Z ≦ 250; (2 ′) (t _1p + t _2p ) /Z≧0.1; and (3 ′) G ₁ × [t _1p / (t _1p + t _2p )] + G ₂ × [t _2p / (t _1p + t _2p )] ≧ 6, and G ₁ is 6 or more.

By using the resin sheet group to form the first and second solder resist layers, the printed wiring board of the present invention that satisfies the conditions (1), (2), and (3) can be easily manufactured.

Condition (1 ') corresponds to the above condition (1). The preferable range of Z is as described in the condition (1).

Condition (2 ') corresponds to the above condition (2). When the resin composition layer is laminated on the circuit substrate to form a solder resist layer, the existence of the surface circuit of the circuit substrate is the cause. Generally, the thickness of the resulting solder resist layer is thicker than the thickness of the resin composition layer. Therefore, by satisfying the condition (2 '), it is easy to satisfy the condition (2) without being affected by the thickness of the surface circuit or the density of the surface circuit of the circuit substrate. In the condition (2 '), when determining the preferred range of the (t _1p + t _2p ) / Z ratio, the "t ₁ " and "t ₂ " in the condition (2) can be interpreted as "t _1p " and "T _2p ". Similarly, when determining the preferred ranges of t _1p and t _2p , in the description of the preferred ranges of t ₁ and t ₂ attached to the above condition (2), "t ₁ " and "t ₂ " _Reapply as "t _1p " and "t _2p " to apply. In addition, when t _1p and t _2p are determined, it is preferable to determine the thickness of these circuits to be the same as or greater than the thickness of the surface circuit of the circuit board.

The condition (3 ') corresponds to the above condition (3). When the elastic modulus (23 ° C) after hardening of the solder resist layer indicates the elastic modulus (23 ° C) after hardening of the resin composition constituting the solder resist layer, as described above, the preferred ranges of G ₁ and G ₂ are: This is as explained under Condition (3). The preferable range of the value on the right side of the condition (3 ') is as described in the condition (3).

From the viewpoint that the warpage of the printed wiring board can be more suppressed in the mounting step, the elastic modulus (200 ° C) after curing of the first and second resin composition layers are G ₁ ′ (GPa) and G ₂ ′, respectively. (GPa), it satisfies the following conditions (4 '): (4') G ₁ '× [t _1p / (t _1p + t _2p )] + G ₂ ' × [t _2p / (t _1p + t _2p )] ≧ 0.2 is preferred. The preferable range of the value on the right side of the condition (4 ′) is as described in the condition (4), and the preferable ranges of G ₁ ′ and G ₂ ′ are as described in the condition (4).

<Resin composition>

The resin composition used in the first and second resin composition layers may be a thermosetting resin composition as long as it exhibits the above-mentioned specific elastic modulus and has sufficient chemical resistance and insulation properties after curing. It may be a photocurable resin composition. Examples of the thermosetting resin composition include a resin composition containing a thermosetting resin and a curing agent. As the thermosetting resin, a conventionally known thermosetting resin used when forming a solder resist layer of a printed wiring board can be used, and among them, epoxy resin is more preferable. Therefore, in one embodiment, the thermosetting resin composition system used in the first and second resin composition layers contains (a) an epoxy resin and (b) a curing agent. Moreover, a preferable photocurable resin composition can be formed by adding a photocurable resin to the said thermosetting resin composition. As for the photocurable resin, a conventionally known photocurable resin used in forming a solder resist layer of a printed wiring board can be used. From the viewpoint of easily performing exposure / development (light lithography) to form an opening, it is based on Light-curing alkali-soluble resin is good. Therefore, in one embodiment, the photocurable resin composition used in the first and second resin composition layers includes (a) an epoxy resin, (b) a curing agent, and (c) a photocurable alkali-soluble resin. . The photocurable resin composition further contains one or more selected from the group consisting of (d) a photopolymerization initiator, (e) a photosensitizer, and (f) a diluent. In addition, in the present invention, a resin composition containing a photocurable resin and capable of forming an opening by light lithography is referred to as a "photocurable resin composition" even when it has thermosetting properties. Regardless of the classification of the thermosetting resin composition and the photocurable resin composition, the resin composition that can be used in the first and second resin composition layers may further include (g) an inorganic filler and (h) heat as needed. Additives such as plastic resin, (i) hardening accelerator, (j) flame retardant, and (k) organic filler.

The following are epoxy resins, hardeners, light-curing alkali-soluble resins, photopolymerization initiators, photosensitizers, and diluents that can be used as materials for the resin composition in the first and second resin composition layers. And additives.

-(a) Epoxy resin-

As for the epoxy resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, Senate phenol epoxy resin, naphthol novolac epoxy resin, phenol novolac epoxy resin, tert-butyl-benzenediol epoxy resin, naphthalene epoxy resin, naphthol epoxy resin, Anthracene epoxy resin, epoxypropylamine epoxy resin, epoxypropyl ester epoxy resin Grease, cresol novolac epoxy resin, biphenyl epoxy resin, linear aliphatic epoxy resin, epoxy resin with butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, Spiro-containing epoxy resin, cyclohexanedimethanol epoxy resin, naphthalene ether epoxy resin, and trimethylol epoxy resin. The epoxy resin may be used singly or in combination of two or more kinds.

The epoxy resin is preferably an epoxy resin having two or more epoxy groups in one molecule. When the non-volatile content of the epoxy resin is 100% by mass, it is preferred that at least 50% by mass or more be an epoxy resin having two or more epoxy groups in one molecule. Among them, epoxy resins having two or more epoxy groups in one molecule and being liquid at a temperature of 20 ° C (hereinafter referred to as "liquid epoxy resins") and three or more epoxy groups in one molecule are further included. In addition, a solid epoxy resin (hereinafter referred to as a "solid epoxy resin") is preferred at a temperature of 20 ° C. As for the epoxy resin, a liquid epoxy resin and a solid epoxy resin are used together to obtain a resin composition having excellent flexibility. In addition, the breaking strength of the solder resist layer formed by curing the resin composition is also improved. In particular, when the resin composition is a thermosetting resin composition, a liquid epoxy resin and a solid epoxy resin are preferably used in combination. When the resin composition is a photocurable resin composition, a solid epoxy resin is preferably used as the epoxy resin.

For liquid epoxy resins, bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac epoxy resin, and naphthalene epoxy resin are preferred. Bisphenol A epoxy resin, Bisphenol F-type epoxy resins and naphthalene-type epoxy resins are more preferred. Specific examples of the liquid epoxy resin include "HP4032", "HP4032D", "HP4032SS" (naphthalene type epoxy resin), "jER828EL" (bisphenol A type epoxy resin), "jER807" (bisphenol F type epoxy resin), "jER152" (phenol novolac) manufactured by Mitsubishi Chemical Corporation Varnish-type epoxy resin), `` ZX1059 '' made by Nippon Steel & Sumitomo Chemical Co., Ltd. (mixed product of bisphenol A-type epoxy resin and bisphenol F-type epoxy resin), and `` EX made by Nagase ChemteX '' -721 "(epoxypropyl ester type epoxy resin). These can be used individually by 1 type or in combination of 2 or more types.

For solid epoxy resins, naphthalene type 4-functional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, ginseng phenol type epoxy resin, and naphthol novolac type epoxy resin are used. Resin, biphenyl type epoxy resin, or naphthyl ether type epoxy resin is preferred, naphthalene type 4 functional epoxy resin, biphenyl type epoxy resin, or naphthyl ether type epoxy resin is more preferred, and naphthalene type 4 functional epoxy resin Resins and biphenyl epoxy resins are even better. Specific examples of the solid epoxy resin include "HP-4700", "HP-4710" (naphthalene-type 4-functional epoxy resin), and "N-690" (cresol novolac) made by DIC. Type epoxy resin), "N-695" (cresol novolac type epoxy resin), "HP-7200" (dicyclopentadiene type epoxy resin), "EXA7311", "EXA7311-G3", " EXA7311-G4 "," EXA7311-G4S "," HP6000 "(naphthyl ether type epoxy resin)," EPPN-502H "(ginsylphenol epoxy resin)," NC7000L "(naphthol) Novolac epoxy resin), `` NC3000H '', `` NC3000 '', `` NC3000L '', `` NC3100 '' (biphenyl type epoxy resin), `` ESN475 '' (naphthol novolac type) made by Nippon Steel & Sumitomo Chemical Co., Ltd. Epoxy resin), `` ESN485V '' (naphthol novolac type epoxy resin), `` YX4000H '' made by Mitsubishi Chemical Corporation, `` YL6121 '' (biphenyl type epoxy resin), `` YX4000HK '' (dixylenol type epoxy resin) , "PG-100", "CG-500" made by Osaka Gas Chemical Co., Ltd., "YL7800" (茀 -type epoxy resin) made by Mitsubishi Chemical Co., Ltd., etc.

In terms of epoxy resin, when liquid epoxy resin and solid epoxy resin are used in combination, the amount ratio (liquid epoxy resin: solid epoxy resin) is based on the mass ratio of 1: 0.1 ~ 1. : The range of 4 is preferable. By setting the amount ratio of the liquid epoxy resin to the solid epoxy resin within this range, the following effects can be obtained: i) when used in the form of a resin sheet, it has moderate adhesiveness, and ii) when it is used in a resin sheet When the form is used, sufficient flexibility can be obtained, and extractability can be improved. Iii) A solder resist layer having sufficient breaking strength can be obtained. From the viewpoint of the effects of i) to iii) above, the amount ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin: solid epoxy resin) is based on a mass ratio of 1: The range of 0.3 ~ 1: 3.5 is better, the range of 1: 0.6 ~ 1: 3 is even better, and the range of 1: 0.8 ~ 1: 2.5 is particularly good.

The content of the epoxy resin in the resin composition is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 7% by mass or more and 9% by mass or more. The upper limit of the content of the epoxy resin is not particularly limited, but is preferably 50% by mass or less, more preferably 45% by mass or less, and still more preferably 40% by mass or less than 35% by mass.

In addition, in this invention, content of each component which comprises a resin composition is a value when the total of the non-volatile matter in a resin composition is 100 mass%.

Epoxy equivalent of epoxy resin, preferably 50 to 3000, more preferably It is 80 ~ 2000, and more preferably 110 ~ 1000. Because of this range, the cured product has a sufficient crosslinking density and has a solder resist layer excellent in heat resistance. The epoxy equivalent is measured in accordance with JIS K7236, and is the mass of a resin containing 1 equivalent of epoxy groups.

The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and even more preferably 400 to 1500. Here, the weight average molecular weight of an epoxy resin is a polystyrene conversion weight average molecular weight measured by the colloidal permeation chromatography (GPC) method.

-(b) Hardener-

The hardening agent is not particularly limited as long as it has a function of hardening an epoxy resin. For example, a phenol-based hardener, a naphthol-based hardener, an active ester-based hardener, a benzoxazine-based hardener, and a cyanate Ester-based hardener. The hardener can be used alone or in combination of two or more.

From the viewpoint of obtaining a solder resist layer having excellent heat resistance and water resistance, phenol-based hardeners and naphthol-based hardeners are phenol-based hardeners having a novolac structure or naphthols having a novolac structure. A hardener is preferred. From the viewpoint of obtaining a solder resist layer having excellent adhesion to a circuit board, a nitrogen-containing phenol-based hardener is preferred, and a triazine skeleton-containing phenol-based hardener is more preferred. Among them, a phenol novolak resin containing a triazine skeleton is more preferred from the viewpoint of obtaining a solder resist layer that satisfies high heat resistance, water resistance, and adhesion to a circuit board.

Specific examples of the phenol-based hardener and naphthol-based hardener include "MEH-7700" manufactured by Meiwa Chemical Co., Ltd., "MEH-7810", "MEH-7851", "NHN", "CBN", "GPH" made by Nippon Kayaku Co., Ltd., "SN170", "SN180", "SN190" made by Tohoku Kasei Co., Ltd. , "SN475", "SN485", "SN495", "SN375", "SN395", "LA7052", "LA7054", "LA3018" made by DIC (shares), etc.

From the viewpoint of obtaining a solder resist layer excellent in heat resistance, an active ester-based hardener is also preferable. There is no particular limitation on the active ester-based hardener. Generally, two or more molecules are used in a molecule having high reactivity such as phenol esters, thiophene esters, N-hydroxyamine esters, and heterocyclic hydroxyl compounds. Ester-based compounds are preferred. The active ester-based hardener is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. Especially from the viewpoint of improvement of heat resistance, an active ester-based hardener obtained from a carboxylic acid compound and a hydroxy compound is preferable, and an active ester-based hardener obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound is preferable. Better. Examples of the carboxylic acid compound include benzoic acid, osmic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthaloline, methylated bisphenol A, methylated bisphenol F, methyl Bisphenol S, phenol, o-cresol, m-cresol, p-cresol, resorcinol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxyl Naphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, 1,3,5-benzenetriol, 1,2,4-benzenetriol , Dicyclopentadiene-type diphenol compounds, phenol novolac, and the like. Here, the so-called "dicyclopentadiene type "Diphenol compound" is a diphenol compound obtained by condensing two molecules of phenol in one molecule of dicyclopentadiene.

Specifically, it is an active ester compound containing a dicyclopentadiene-type diphenol structure, an active ester compound containing a naphthalene structure, an active ester compound containing an acetamidate of a phenol novolak, and a benzyl containing a phenol novolac. An active ester compound of a fluorenyl compound is preferable. Among them, an active ester compound containing a naphthalene structure and an active ester compound containing a dicyclopentadiene type diphenol are more preferable. The "dicyclopentadiene-type diphenol structure" means a divalent structural unit formed by phenylene-dicyclopentadiene-phenylene.

In terms of commercially available active ester hardeners, as for active ester compounds containing a dicyclopentadiene-type diphenol structure, "EXB9451", "EXB9460", "EXB9460S", "HPC-8000-65T" ( DIC (product), naphthalene-containing active ester compounds, "EXB9416-70BK" (product of DIC (stock)), active ester compounds containing phenol novolak ethoxylates, etc. "DC808" (manufactured by Mitsubishi Chemical Corporation), and the active ester compound of the benzamidine compound containing phenol novolac, include "YLH1026" (manufactured by Mitsubishi Chemical Corporation).

Specific examples of the benzoxazine-based hardener include "HFB2006M" manufactured by Showa Polymer Co., Ltd., "P-d" and "F-a" manufactured by Shikoku Chemical Industry Co., Ltd.

Examples of the cyanate ester-based hardener include bisphenol A dicyanate, polyphenol cyanate, oligo (3-methylene-1,5-phenylene cyanate), 4,4 '-Methylenebis (2,6-dimethylphenylcyanate), 4,4'-Asia Ethyl diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis (4-cyanate) phenylpropane, 1,1-bis (4-cyanate phenylmethane) ), Bis (4-cyanate-3,5-dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (methylethylene)) benzene, bis ( Bifunctional cyanate resins such as 4-cyanate phenyl) sulfide and bis (4-cyanate phenyl) ether; polyfunctional cyanates derived from phenol novolac and cresol novolac Resins, such as cyanate resins, a part of which is a triazinated prepolymer, and the like. Specific examples of the cyanate ester-based hardener include "PT30" and "PT60" (both phenol novolac-type polyfunctional cyanate ester resins) and "BA230" (bisphenol A bis manufactured by Lonza Japan). Some or all of the cyanate esters are triazinated and formed into trimeric prepolymers).

The ratio of the amount to the epoxy resin and the hardener is preferably a ratio of [total number of epoxy groups of the epoxy resin]: [total number of reactive groups of the hardener]: 1: 0.2 to 1: 2 The range is more preferably 1: 0.3 ~ 1: 1.5, and more preferably 1: 0.4 ~ 1: 1.2. Here, the reactive groups of the hardener, such as an active hydroxyl group, an active ester group, and the like, differ depending on the type of the hardener. The total number of epoxy groups of an epoxy resin refers to the total value of all epoxy resins obtained by dividing the solid content of each epoxy resin by the epoxy equivalent. The reaction group of the so-called hardener The total count refers to the total value of all hardeners obtained by dividing the solid content of each hardener by the value of the reactive group equivalent. By setting the amount ratio of the epoxy resin to the hardener within this range, the heat resistance of the obtained solder resist layer can be further improved.

-(c) Light-curing alkali-soluble resin-

The light-curable alkali-soluble resin is not particularly limited as long as it is a light-curable resin containing an alkali-soluble group (for example, a carboxyl group, a phenolic hydroxyl group, or the like). It can also be used when forming a solder resist layer for a printed wiring board. A conventionally known photocurable alkali-soluble resin. Among them, the light-curable alkali-soluble resin is preferably a resin containing an alkali-soluble group and a radical polymerizable unsaturated group, a resin containing a carboxyl group and a radical polymerizable unsaturated group, a resin containing a phenolic hydroxyl group, and Radical polymerizable unsaturated resins are more preferred. The light-curable alkali-soluble resin may be used singly or in combination of two or more kinds.

As the resin containing a carboxyl group and a radically polymerizable unsaturated group, for example, an acid fork type unsaturated epoxy ester resin formed by reacting an epoxy resin with an unsaturated carboxylic acid and then reacting an acid anhydride with the acid anhydride may be used.

In terms of epoxy resin, it is only necessary to use the same component as (a). From the viewpoint of obtaining good developability and insulation reliability, bisphenol F-type epoxy resin and bisphenol A-type epoxy resin are used. Resins and cresol novolac epoxy resins are preferred, and bisphenol F-type epoxy resins and cresol novolac epoxy resins are more preferred. An epoxy resin may be used individually by 1 type, and may use 2 or more types together.

Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, cinnamic acid, and crotonic acid, and acrylic acid and methacrylic acid are preferred from the viewpoint of obtaining good photohardening characteristics. The unsaturated carboxylic acid may be used singly or in combination of two or more kinds.

Examples of carboxylic anhydrides include anhydrous maleic acid, anhydrous succinic acid, anhydrous itaconic acid, anhydrous phthalic acid, anhydrous tetrahydrophthalic acid, anhydrous hexahydrophthalic acid, anhydrous trimellitic acid, and anhydrous pyromellitic acid. Formic acid, From the viewpoint of obtaining good developability and insulation reliability, benzophenonetetracarboxylic acid dihydrate and the like are preferably anhydrous succinic acid and anhydrous tetrahydrophthalic acid. An acid anhydride may be used individually by 1 type, and may use 2 or more types together.

In the presence of a catalyst, the acid fork type unsaturated epoxy ester resin is formed by reacting an unsaturated carboxylic acid with an epoxy resin to form an unsaturated epoxy ester resin. Derived from acid anhydride reaction. This reaction system is well known, and reaction conditions such as reaction temperature, reaction time, type of catalyst, and amount of use may be appropriately determined by those skilled in the art.

A commercially available product can also be used for the acid fork type unsaturated epoxy ester resin. For commercially available products, for example, "ZFR-1533H" (reactant of bisphenol F-type epoxy resin, acrylic acid, and anhydrous tetrahydrophthalic acid) made by Nippon Kayaku Co., Ltd., and "ZAR-2000" (double Reactant of phenol A type epoxy resin, acrylic acid, and anhydrous succinic acid), "PR-3000" (reactant of cresol novolac epoxy resin, acrylic acid, and carboxylic anhydride) manufactured by Showa Denko Corporation.

The resin containing a phenolic hydroxyl group and a radical polymerizable unsaturated group can be synthesized by, for example, reacting a resin containing a phenolic hydroxyl group with a compound containing a radical polymerizable unsaturated group and an isocyanate group.

Examples of the phenolic hydroxyl-containing resin include phenol novolac resin, cresol novolac resin, bisphenol A novolac resin, and naphthol novolac resin. From the viewpoint of obtaining good developability and insulation reliability, Look, it is better to use phenol novolac resin, cresol novolac resin. The phenolic hydroxyl group-containing resin may be used singly or in combination of two or more kinds.

For compounds containing a radically polymerizable unsaturated group and an isocyanate group, for example, a (meth) acrylfluorenyl isocyanate, an isocyanate ethyl (meth) acrylate; and a polyisocyanate compound with a compound capable of reacting with an isocyanate group A reaction product or the like obtained by a partial addition reaction of a (meth) acrylate compound having a functional group (for example, a hydroxyl group). Examples of the polyisocyanate compound include 3-isocyanate-3,5,5-trimethylcyclohexyl isocyanate, trichloroethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and methylene Examples of the (meth) acrylate compound having a functional group capable of reacting with an isocyanate group, such as biphenyl isocyanate, polymethylene polyphenyl polyisocyanate, pentaerythritol tri (meth) acrylate, 2- Hydroxyethyl (meth) acrylate, N-hydroxymethacrylamide, glycerol di (meth) acrylate, dipentaerythritol penta (meth) acrylate, and the like.

The resin containing a phenolic hydroxyl group and a radical polymerizable unsaturated group can be obtained by reacting a resin containing a phenolic hydroxyl group with a compound containing a radical polymerizable unsaturated group and an isocyanate group in the presence of a catalyst. This reaction system is well known, and reaction conditions such as reaction temperature, reaction time, type of catalyst, and amount of use may be appropriately determined by those skilled in the art.

The polystyrene-equivalent number-average molecular weight (Mn) of the photocurable alkali-soluble resin is preferably from 500 to 1,000,000, more preferably from 1,000 to 50,000, and even more preferably from the viewpoint of obtaining good resolution. 1500 ~ 35000. The Mn of the photocurable alkali-soluble resin can be measured, for example, by a colloidal permeation chromatography (GPC) method. (GPC) method (polystyrene equivalent) can be measured. Mn is produced, for example, by Shimadzu Corporation LC-9A / RID-6A was used as a measuring device. Shodex K-800P / K-804L / K-804L manufactured by Showa Denko Corporation was used for the column. The mobile phase was chloroform. The column temperature was measured at 40 ° C. Calculated using a standard polystyrene calibration curve.

From the viewpoint of obtaining a solder resist layer exhibiting good insulation reliability, the solid acid value of the photocurable alkali-soluble resin is preferably 100 mgKOH / g or less, more preferably 90 mgKOH / g or less, and even more preferably It is 80 mgKOH / g or less or 70 mgKOH / g or less. As long as sufficient developability can be obtained, it is preferable that the solid acid value is lower. From this viewpoint, the light-curable alkali-soluble resin is based on a phenolic hydroxyl group and a radical polymerizable polymer. Saturated resins are particularly preferred.

The content of the photocurable alkali-soluble resin in the resin composition is preferably 10% by mass or more, more preferably 15% by mass or more, and still more preferably 20% by mass or more from the viewpoint of obtaining good developability. . The upper limit of the content of the photocurable alkali-soluble resin is preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 40% by mass or less from the viewpoint of obtaining a solder resist layer having excellent heat resistance.

-(d) Photopolymerization initiator-

The photopolymerization initiator is not particularly limited, and examples thereof include 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) -1-butanone and 2- (dimethylformate). Methylamino) -2-[(4-methylphenyl) methyl]-[4- (4-morpholinyl) phenyl] -1-butanone, 2-methyl- [4- (methyl Thio) phenyl] -morpholinyl-1-acetone, benzophenone, methylbenzophenone, o-benzyl benzoin Acid, benzamidine ethyl ether, 2,2-diethoxyacetophenone, 2,4-diethylthioxanthone, bis (2,4,6-trimethylbenzoyl (Fluorenyl) -phenylphosphine oxide, ethyl- (2,4,6-trimethylbenzylidene) phenylphosphonate, 4,4'-bis (diethylamino) dibenzoyl Ketone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1- [4- (2-hydroxyethoxy)- Phenyl] -2-hydroxy-2-methyl-1-propane-1-one and other alkyl-benzene-based photopolymerization initiators; bis (2,4,6-trimethylbenzyl)- Phenylphosphine oxide-based photopolymerization initiators such as phenylphosphine oxide; 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzidine Oxime)] and ethyl ketone, 1- [9-ethyl-6- (2-methylbenzylidene) -9H-carbazol-3-yl]-, 1- (O-acetamidooxime) Among the oxime ester-based photopolymerization initiators; and the sulfonium salt-based photopolymerization initiators, fluorenylphosphine oxide-based photopolymerization initiators and oxime ester-based photopolymerization initiators are preferred. The photopolymerization initiator may be used singly or in combination of two or more kinds.

Examples of commercially available photopolymerization initiators include "IRGACURE 819" (bis (2,4,6-trimethylbenzyl) -phenylphosphine oxide) manufactured by BASF JAPAN, and " IRGACURE 907 "(2-methyl- [4- (methylthio) phenyl] -morpholinyl-1-acetone)," OXE-01 "(1,2-octanedione, 1- [ 4- (phenylthio)-, 2- (O-benzylideneoxime)]), "OXE-02" (ethyl ketone, 1- [9-ethyl-6- (2-methylbenzene Formamyl) -9H-carbazol-3-yl]-, 1- (O-acetamidooxime)) and the like.

The content of the photopolymerization initiator in the resin composition is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and still more preferably 0.3 from the viewpoint of obtaining good photohardening characteristics and insulation reliability. quality Amount above. The upper limit of the content of the photopolymerization initiator is preferably 2% by mass or less, more preferably 1.5% by mass or less, and still more preferably 1% by mass or less from the viewpoint of preventing reduction in dimensional stability due to excessive sensitivity. .

-(e) Photosensitizer-

As for the photosensitizer, for example, tertiary amines, pyrarizones, anthracenes, coumarins, xanthone, thioxanthone, etc., of which thioxanthone is preferred, 2,4-Diethylthioxanthone is more preferred. The photosensitizer may be used alone or in combination of two or more. As a commercially available product of a photosensitizer, for example, "DETX-S" (2,4-diethylthioxanthone) manufactured by Nippon Kayaku Co., Ltd. may be mentioned.

The content of the photosensitizer in the resin composition is preferably from 0.01% by mass to 1% by mass, and more preferably from 0.05% by mass to 0.5% by mass from the viewpoint of obtaining good photohardening characteristics.

-(f) Thinner-

The diluent is used to promote the photo-hardening reaction of the resin composition. As a diluent, the photosensitive (meth) acrylate compound which is liquid, solid, or semi-solid at room temperature which has one or more (meth) acryl fluorenyl group in a molecule | numerator is mentioned, for example.

Examples of the photosensitive (meth) acrylate compounds include hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxybutyl acrylate; ethylene glycol and methoxytetraethylene glycol Alcohol, polyethylene glycol, propylene glycol, tricyclodecane dimethanol, etc. Diacrylates; acrylamides such as N, N-dimethylacrylamide, N-hydroxymethacrylamide; amine alkyl groups such as N, N-dimethylaminoethylacrylate Acrylates; polyhydric alcohols such as trimethylolpropane, pentaerythritol, dipentaerythritol, and the like, or polyvalent acrylates of ethylene oxide, propylene oxide, or ε-caprolactone; phenoxy acrylates, Phenols such as phenoxyethyl acrylate or acrylates such as ethylene oxide or propylene oxide adducts; rings derived from glycidyl ether such as trimethylolpropane triglycidyl ether Oxyacrylates; melamine acrylates; and / or methacrylates corresponding to the aforementioned acrylates. Among them, mono- or di (meth) acrylates and polyvalent (meth) acrylates of diol compounds are more preferred.

The diluent may be used alone or in combination of two or more. Examples of commercially available thinners include, for example, Nippon Kayaku Co., Ltd. "DPHA" (dipentaerythritol hexaacrylate), and "DCPA" (tricyclodecane dimethanol diacrylate) manufactured by Kyoeisha Chemical Industry Co., Ltd. )Wait.

The content of the diluent in the resin composition is preferably from 0.5% by mass to 10% by mass, and more preferably from 2% by mass to 8% by mass, from the viewpoint of promoting the photo-hardening reaction and preventing the adhesion of the cured product.

-(g) inorganic filler-

In terms of inorganic fillers, there can be mentioned, for example, silica, alumina, glass, apatite, silicic acid, barium sulfate, talc, clay, mica powder, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, Boron nitride, aluminum nitride, manganese nitride, aluminum borate, barium titanate, strontium titanate, calcium titanate, titanic acid Magnesium, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, amorphous silicon oxide, fused silicon oxide, crystalline silicon oxide, synthetic silicon oxide, and hollow silicon oxide are particularly preferred. In terms of silicon oxide, spherical silicon oxide is preferred. The inorganic fillers may be used singly or in combination of two or more kinds. For commercially available spherical fused silica, for example, "SOC1", "SOC2", "SOC3", and "SOC4" manufactured by Admatechs, "UFP-30" manufactured by Denki Chemical Industries, and "UFP- 80 ".

The average particle diameter of the inorganic filler is not particularly limited, and may be appropriately determined depending on the desired characteristics. From the viewpoint of improving the dispersibility of the inorganic filler, the average particle diameter of the inorganic filler is preferably 0.01 μm or more, and more preferably 0.05 μm or more. From the viewpoint of obtaining sufficient insulation reliability, the average particle diameter of the inorganic filler is preferably 4 μm or less, more preferably 3 μm or less, even more preferably 2 μm or less, and still more preferably 1 μm or less. In addition, when the resin composition is a photocurable resin composition, the upper limit of the average particle diameter of the inorganic filler is preferably 1 μm or less, more preferably 0.8 μm or less, from the viewpoint of obtaining good photohardening characteristics. It is more preferably 0.6 μm or less or 0.4 μm or less. The average particle size of the inorganic filler is based on laser diffraction based on Mie scattering theory. Scattering method. Specifically, with a laser diffraction scattering type particle size distribution measuring device, the particle size distribution of the inorganic filler can be prepared on a volume basis, and the median diameter is taken as the average particle size for measurement. For the measurement sample, the inorganic filler is preferably dispersed in water by ultrasonic waves. For laser diffraction scattering particle size distribution measurement devices, Horiba Ltd. "LA-500" and so on.

From the viewpoint of improving moisture resistance and dispersibility, inorganic fillers are available in the form of amine-based silane coupling agents, epoxy silane-based coupling agents, mercapto silane-based coupling agents, silane-based coupling agents, and organic silazane compounds. And titanate-based coupling agents are preferred. Commercially available surface treatment agents include, for example, "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd., and "KBM803" (3) manufactured by Shin-Etsu Chemical Industry Co., Ltd. -Testylpropyltrimethoxysilane), `` KBE903 '' (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd., and `` KBM573 '' (N-phenyl) manufactured by Shin-Etsu Chemical Industry Co., Ltd. -3-aminopropyltrimethoxysilane), "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Industry Co., Ltd., and the like.

The degree of surface treatment achieved by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. The carbon content per unit surface area of the inorganic filler is preferably 0.02 mg / m ² or more, more preferably 0.1 mg / m ² or more, and 0.2 mg / m ² or more from the viewpoint of improving the dispersibility of the inorganic filler. Even better. On the other hand, from the viewpoint of preventing an increase in the melt viscosity of the resin paint or the melt viscosity in the form of a sheet, it is preferably 1 mg / m ² or less, more preferably 0.8 mg / m ² or less, and 0.5 mg / m ² The following is even better.

The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (for example, methyl ethyl ketone (MEK)). Specifically, in terms of solvents, a sufficient amount of MEK can be added to the surface treatment of the surface treatment agent. The inorganic filler was ultrasonically cleaned at 25 ° C for 5 minutes. After removing the supernatant and drying the solid content, the carbon content per unit surface area of the inorganic filler was measured using a carbon analyzer. For the carbon analysis meter, "EMIA-320V" manufactured by Horiba Ltd. can be used.

The content of the inorganic filler in the resin composition is not particularly limited under a solder resist layer that can exhibit a desired elastic modulus. Although it depends on the kind of epoxy resin or hardener, if the content of the inorganic filler in the resin composition is increased, the elastic modulus of the resin composition after curing tends to be high. For example, a resin composition layer that exhibits a high elastic modulus (23 ° C) of 6 GPa or more after curing, and when forming a solder resist layer, the content of the inorganic filler in the resin composition is preferably 60% by mass or more. A resin composition layer having a higher elastic modulus (23 ° C) after curing, and when forming a solder resist layer, the content of the inorganic filler in the resin composition is more preferably 65% by mass or more, and 70% by mass or more. Or more preferably 75% by mass or more.

In one embodiment, the content of the inorganic filler in the first resin composition layer and further in the resin composition used in the first solder resist layer is preferably 60% by mass or more, more preferably 65% by mass or more, and even more It is preferably 70% by mass or more or 75% by mass or more. The upper limit of the content of the inorganic filler in the resin composition used in the first resin composition layer is not particularly limited. From the viewpoint of the mechanical strength of the obtained solder resist layer, it is usually 95% by mass or less, and may be 90% by mass or less.

The content of the inorganic filler in the resin composition used in the second resin composition layer and further in the second solder resist layer is such that In the case of the second solder resist layer showing a desired elastic modulus, it may be appropriately determined in accordance with the desired characteristics, and it is preferably in a range from 0% to 95% by mass, and more preferably 20%. The range of mass% to 85 mass% is preferably determined as appropriate.

In a preferred embodiment, the resin composition-based thermosetting resin composition used in the first resin composition layer includes the aforementioned (a) epoxy resin, (b) curing agent, and (g) inorganic Filling material. In this embodiment, the thermosetting resin composition used in the first resin composition layer preferably contains the following components: (a) liquid epoxy resin and solid epoxy resin as epoxy resin The mixture made of resin (liquid epoxy resin: solid epoxy resin has a mass ratio in the range of 1: 0.1 ~ 1: 4, more preferably in the range of 1: 0.3 ~ 1: 3.5, 1: 0.6 ~ The range of 1: 3 is even better, and the range of 1: 0.8 ~ 1: 2.5 is even better.) (B) Hardeners include phenol-based hardeners, naphthol-based hardeners, active ester-based hardeners, and cyanic acid. One or more selected from the group consisting of an ester-based hardener (preferably one or more selected from the group consisting of a phenol-based hardener, a naphthol-based hardener, and an active ester-based hardener), as (g) Silicon oxide for inorganic fillers. The preferable content of (a) an epoxy resin, (b) a hardening | curing agent, and (g) an inorganic filler containing the thermosetting resin composition formed by combining this specific component is as mentioned above.

In another preferred embodiment, the resin composition-based photocurable resin composition used in the first resin composition layer is (a) an epoxy resin, (b) a curing agent, and (c) a photocuring type. The alkali contains a soluble resin and (g) an inorganic filler. In this embodiment, the first resin The photocurable resin composition used in the composition layer preferably contains the following components: (a) a mixture of a liquid epoxy resin and a solid epoxy resin (liquid ring) The mass ratio of oxygen resin: solid epoxy resin is preferably in the range of 1: 0.1 ~ 1: 4, more preferably in the range of 1: 0.3 ~ 1: 3.5, and more preferably in the range of 1: 0.6 ~ 1: 3. The range of 1: 0.8 ~ 1: 2.5 is even better) or only solid epoxy resin, phenol-based hardener, naphthol-based hardener, active ester-based hardener, and cyanate ester as (b) hardener One or more selected from the group consisting of an ester-based hardener (preferably one or more selected from the group consisting of a phenol-based hardener, a naphthol-based hardener, and an active ester-based hardener), and (c) light curing Type alkali-soluble resins containing alkali-soluble groups and radically polymerizable unsaturated groups (preferably resins containing carboxyl groups and radically polymerizable unsaturated groups, resins containing phenolic hydroxyl groups and radically polymerizable unsaturated groups) A resin, more preferably a resin containing a phenolic hydroxyl group and a radically polymerizable unsaturated group), and (g) silica as an inorganic filler. The preferable content of the thermosetting resin composition containing (a) an epoxy resin, (b) a hardener, (c) a photocurable alkali-soluble resin, and (g) an inorganic filler in combination with the specific component As described above, from the viewpoint of obtaining good heat resistance, insulation reliability, and developability, when (c) the non-volatile content of the photocurable alkali-soluble resin is 100% by mass, (a) the ring The oxygen resin is preferably 5 mass% to 100 mass%, and more preferably 10 mass% to 85% by mass. In addition, when the resin composition used in the first resin composition layer is a photocurable resin composition, the photocurable resin composition further contains (d) a photopolymerization initiator and (e) photoincrease. One or more selected from the group consisting of sensitizer and (f) diluent are good.

From the viewpoint that the warpage of the printed wiring board can be further suppressed in the mounting step, the resin composition used in the first resin composition layer and further the first solder resist layer does not matter the thermosetting resin composition and the photocurable resin. The type of the composition is preferably a glass transition temperature (Tg) after curing of 150 ° C or higher, more preferably 155 ° C or higher. The upper limit of the Tg is not particularly limited, but is usually 300 ° C or lower, and may be 250 ° C or lower. The Tg of the cured resin composition can be measured by a thermomechanical analysis by a tensile weighting method. Examples of thermomechanical analysis devices that can be used for the measurement of the cured resin composition Tg include, for example, "Thermo Plus TMA8310" manufactured by Rigaku, and "TMA-SS6100" manufactured by Seiko Instruments.

In a preferred embodiment, the resin composition-based thermosetting resin composition used in the second resin composition layer contains the above-mentioned (a) epoxy resin and (b) curing agent. In this embodiment, the thermosetting resin composition used in the second resin composition layer preferably contains the following components: (a) liquid epoxy resin and solid epoxy resin as epoxy resin The resulting mixture (the mass ratio of liquid epoxy resin: solid epoxy resin is preferably in the range of 1: 0.1 ~ 1: 4, more preferably in the range of 1: 0.3 ~ 1: 3.5, 1: 0.6 ~ 1 : The range of 3 is even better, and the range of 1: 0.8 to 1: 2.5 is even better.) (B) Hardeners from phenol-based hardeners, naphthol-based hardeners, active ester-based hardeners, and cyanic acid One or more selected from the group consisting of an ester-based hardener (preferably one or more selected from the group consisting of a phenol-based hardener, a naphthol-based hardener, and an active ester-based hardener). Have Regarding the thermosetting resin composition containing the specific component, the preferable content of (a) the epoxy resin and (b) the hardener is as described above. The thermosetting resin composition used in the second resin composition layer is also the same as described above. In order to achieve the second solder resist layer showing a desired elastic modulus, it contains (g) an inorganic filler (preferably silicon oxide). The content of the resin composition is in a range of 0% by mass to 95% by mass. Here, the term “contained in the range of 0% by mass to n% by mass” of the constituents of the resin composition includes both cases where the constituents are not included and cases where the constituents are contained in a range of n% by mass or less.

In another preferred embodiment, the resin composition-based photocurable resin composition used in the second resin composition layer includes the aforementioned (a) epoxy resin, (b) curing agent, and (c) light. Hardening alkali soluble resin. In this embodiment, the photocurable resin composition used in the second resin composition layer preferably contains the following components: (a) liquid epoxy resin and solid epoxy resin as epoxy resin The resulting mixture (the mass ratio of liquid epoxy resin: solid epoxy resin is preferably in the range of 1: 0.1 ~ 1: 4, more preferably in the range of 1: 0.3 ~ 1: 3.5, 1: 0.6 ~ 1 : The range of 3 is even better, and the range of 1: 0.8 to 1: 2.5 is even better) or only solid epoxy resin, phenol-based hardener, naphthol-based hardener, (b) hardener, One or more selected from the group consisting of an active ester-based hardener and a cyanate ester-based hardener (preferably one selected from the group consisting of a phenol-based hardener, a naphthol-based hardener, and an active ester-based hardener (Above), (c) A resin containing an alkali-soluble group and a radical polymerizable unsaturated group (preferably containing a carboxyl group and Resin having a polymerizable unsaturated group, resin containing a phenolic hydroxyl group and a radical polymerizable unsaturated group, and more preferably resin containing a phenolic hydroxyl group and a radical polymerizable unsaturated group). Regarding the thermosetting resin composition containing the specific component, the preferable content of (a) epoxy resin, (b) hardener, and (c) light-curable alkali-soluble resin is as described above, but it is good from From the viewpoints of heat resistance, insulation reliability, and developability, (a) epoxy resin is preferably 5% by mass when the nonvolatile content of (c) photocurable alkali-soluble resin is 100% by mass. ~ 100% by mass, more preferably 10% to 85% by mass. When the resin composition is a photocurable resin composition used in the second resin composition layer, the photocurable resin composition further includes (d) a photopolymerization initiator and (e) photosensitization. One or more selected from the group consisting of an agent and (f) a diluent are preferred. The photocurable resin composition used in the second resin composition layer is also the same as above. In order to achieve the second solder resist layer showing a desired elastic modulus, the content of the resin composition is 0% to 95% by mass. The range may include (g) an inorganic filler (preferably silicon oxide).

Regardless of the type of the thermosetting resin composition or the photocurable resin composition, the resin composition used in the second resin composition layer and further in the second solder resist layer, as long as the desired elastic modulus is obtained, after curing, The glass transition temperature (Tg) is not particularly limited. From the viewpoint that the warpage of the printed wiring board can be more suppressed in the mounting step, the Tg of the second resin composition layer and further the resin composition used in the second solder resist layer after curing is 150 ° C or higher. Good, those above 155 ° C are more preferred. The upper limit of the Tg is not particularly limited, but is usually 300 ° C or lower, and may be 250 ° C or lower. Wait.

In a preferred embodiment, the resin compositions used in the first and second resin composition layers are both thermosetting resin compositions. In other preferred embodiments, the resin composition used in the first and second resin composition layers is a photocurable resin composition. In another preferred embodiment, the resin composition is a thermosetting resin composition used in the first resin composition layer, and the resin composition is a photocurable resin composition used in the second resin composition layer. Thing. In other preferred embodiments, the resin composition used in the first resin composition layer is a photocurable resin composition, and the resin composition used in the second resin composition layer is a thermosetting resin composition.

-(h) Thermoplastic resin-

The resin composition used in the first and second resin composition layers may further include a thermoplastic resin. In terms of thermoplastic resins, when forming a solder resist layer of a printed wiring board, any generally available thermoplastic resin can be used, such as phenoxy resin, polyvinyl acetal resin, polyolefin resin, and polybutadiene. Resin, polyimide resin, polyimide resin, polyether resin, polyphenylene ether resin, polyimide resin, etc. The thermoplastic resin may be used singly or in combination of two or more kinds.

The polystyrene equivalent weight average molecular weight of the thermoplastic resin is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and even more preferably in the range of 20,000 to 60,000. Polystyrene-equivalent weight average molecular weight of thermoplastic resin is based on colloidal permeation chromatography (GPC) method. Specifically, the polystyrene-equivalent weight average molecular weight of the thermoplastic resin is measured using LC-9A / RID-6A manufactured by Shimadzu Corporation, and Shodex K-800P / manufactured by Showa Denko Corporation is used for the string. For K-804L / K-804L and mobile phase, chloroform was used to measure at a column temperature of 40 ° C, and calculated using a standard polystyrene calibration curve.

The content of the thermoplastic resin in the resin composition is not particularly limited as long as a solder resist layer exhibiting a desired elasticity is obtained, preferably 0.1 mass% or more, more preferably 1 mass% or more, and even more preferably 3 More than mass%, more than 5 mass% or more than 7 mass%. The upper limit of the content of the thermoplastic resin is not particularly limited, but is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less. Although it varies depending on the type of the epoxy resin or the hardener and the content of the inorganic filler, if the content of the thermoplastic resin is increased in the resin composition, the cured composition tends to have a lower elastic modulus.

-(i) Hardening accelerator-

The resin composition used in the first and second resin composition layers may further include a hardening accelerator. In the case of a hardening accelerator, when forming a solder resist layer of a printed wiring board, any hardening accelerator generally used may be used, and examples thereof include a phosphorus-based hardening accelerator, an amine-based hardening accelerator, and an imidazole-based hardening accelerator. As the guanidine-based hardening accelerator, a phosphorus-based hardening accelerator, an amine-based hardening accelerator, or an imidazole-based hardening accelerator is preferred, and an amine-based hardening accelerator or an imidazole-based hardening accelerator is more preferred. Hardening accelerator can be used alone Use 1 type, or you can combine 2 or more types.

The content of the hardening accelerator in the resin composition is not particularly limited as long as a solder resist layer showing a desired elasticity is obtained. When the total amount of the non-volatile components of the epoxy resin and the hardener is 100% by mass, it is based on It is preferably used in the range of 0.03 mass% to 3 mass%.

-(j) Flame retardant-

The resin composition used in the first and second resin composition layers may further contain a flame retardant. In terms of flame retardants, any flame retardant generally used in forming a solder resist layer of a printed wiring board can be used, and examples thereof include organic phosphorus-based flame retardants, organic nitrogen-containing phosphorus compounds, nitrogen compounds, and polysiloxanes. Flame retardants, metal hydroxides, etc. The flame retardant can be used alone or in combination of two or more. The content of the flame retardant in the resin composition is not particularly limited as long as a solder resist layer exhibiting a desired elasticity is obtained, and is preferably 0.5% to 20% by mass, and more preferably 1% to 15% by mass. .

-(k) Organic Filler-

The resin composition used in the first and second resin composition layers may further include an organic filler. In terms of organic fillers, in forming a solder resist layer of a printed wiring board, any organic fillers generally used can be used, such as rubber particles, polyamide fine particles, and polysiloxane particles. Rubber particles are preferred.

In the case of rubber particles, if the resin exhibits rubber elasticity is chemically cross-linked and is insoluble and insoluble in organic solvents The fine particles are not particularly limited, and examples thereof include acrylonitrile butadiene rubber particles, butadiene rubber particles, and acrylic rubber particles. In terms of rubber particles, specifically, XER-91 (made by Japan Synthetic Rubber Co., Ltd.), Staphiroid AC3355, AC3816, AC3816N, AC3832, AC4030, AC3364, IM101 (above, manufactured by GANTSU KASEI), Pararoid EXL2655, EXL2602 ( Above, Wu Yu Chemical Industry Co., Ltd.).

The average particle diameter of the organic filler is preferably in a range of 0.005 μm to 1 μm, and more preferably in a range of 0.2 μm to 0.6 μm. The average particle diameter of an organic filler can be measured using a dynamic light scattering method. For example, an organic filler can be uniformly dispersed in a suitable organic solvent by ultrasonic waves, etc., and an organic filler can be prepared on a mass basis using a thick particle size analyzer (FPAR-1000; manufactured by Otsuka Electronics Co., Ltd.). The particle size distribution is determined by taking the median diameter as the average particle diameter.

The content of the organic filler in the resin composition is not particularly limited as long as a solder resist layer exhibiting a desired elasticity is obtained, and is preferably 0.1% by mass to 6% by mass, and more preferably 0.5% by mass to 4% by mass. .

-Other ingredients-

The resin composition used in the first and second resin composition layers may include other additives as necessary. Examples of the other additives include organometallic compounds such as organic copper compounds, organic zinc compounds, and organic cobalt compounds, and Resin additives such as tackifiers, defoamers, leveling agents, adhesion imparting agents, and coloring agents.

<Support body>

Regarding the support, regardless of the difference between the first support and the second support, for example, a film made of a plastic material, a metal foil, and a release paper, and a film made of a plastic material and a metal foil are preferred.

For the support, when using a thin film made of a plastic material, for example, polyethylene terephthalate (hereinafter referred to as "PET"), polyethylene naphthalate (hereinafter referred to as "" PEN ") and other polyesters, polycarbonates (hereinafter referred to as" PC "), polymethyl methacrylate (PMMA) and other acrylates, cyclic polyolefins, triethyl cellulose (TAC), polymer Ether sulfide (PES), polyether ketone, polyimide, etc. Among them, polyethylene terephthalate and polyethylene naphthalate are more preferable, and valence polyethylene terephthalate is particularly preferable.

For the support, when a metal foil is used, for the metal foil, copper foil, aluminum foil, etc. may be mentioned, and copper foil is preferred. As for the copper foil, a foil made of a single metal of copper can be used, or a foil made of an alloy of copper and other metals (for example, tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) can be used.

The support may be subjected to a matting treatment or a corona treatment on the surface bonded to the resin composition layer. Moreover, as a support body, you may use the support body which has a release layer on the surface joined to the resin composition layer, and the release layer. Examples of the release agent used on the release layer of the support with the release layer include alkyd resin, polyolefin resin, urethane resin, and silicone resin. One or more release agents selected by the group.

As for the commercially available products of the support, for example, SK-1, AL-5, and AL-7 made by LINTEC (stock), NS80A made by Toray (stock), and Mitsubishi Resin (stock) "R310-16B" and so on.

The thickness of the support is not particularly limited, but a range of 5 μm to 75 μm is preferred, a range of 10 μm to 60 μm is more preferred, and a range of 10 μm to 45 μm is more preferred. In addition, when a support with a release layer is used, the thickness of the entire support of the release layer is preferably within the above range.

Regardless of the difference between the first resin sheet and the second resin sheet, for example, the resin coating can be prepared by dissolving the resin composition in an organic solvent, and the resin coating can be applied to a support using a mold coater or the like. It is made by drying the resin paint.

In terms of organic solvents, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, ethyl acetate, butyl acetate, celex acetate, propylene glycol monomethyl ether acetate, and carbitol Acetates such as acetates, carbitols such as cyrus and butyl carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, and Amidamine-based solvents such as N-methylpyrrolidone and the like. The organic solvents may be used alone or in combination of two or more.

The drying of the resin coating can be performed by a known drying method such as heating or hot air blowing. Although it depends on the boiling point of the organic solvent in the resin coating, for example, when using a resin coating containing 30% to 60% by mass of an organic solvent, it can be dried at 50 ° C to 150 ° C for 3 minutes. ~ 10 minutes, and a resin composition layer was formed on the support.

Regardless of the difference between the first resin sheet and the second resin sheet, the resin sheet may further include a protective film on the surface of the resin composition layer that is not bonded to the support (that is, the surface on the opposite side to the support). The protective film acts to prevent adhesion or damage of dirt and the like on the surface of the resin composition layer. As the material of the protective film, the same materials as those described for the support can be used. The thickness of the protective film is not particularly limited, and is, for example, 1 μm to 40 μm. The resin sheet is used for producing a printed wiring board by peeling off the protective film.

[Manufacturing method of printed wiring board]

In the case where a printed wiring board that satisfies the above conditions (1), (2), and (3) can be obtained, the method of manufacturing the printed wiring board of the present invention is not particularly limited. Hereinafter, a method for manufacturing a printed wiring board using the resin sheet for a solder resist layer of the printed wiring board described above will be described as a preferred example of a method for manufacturing the printed wiring board of the present invention.

In a preferred embodiment, the printed wiring board of the present invention is manufactured by a method including the following steps (I) to (III) using the resin sheet group for a solder resist layer of the printed wiring board.

(I) A first resin sheet including a first support and a first resin composition layer bonded to the first support on a first main surface of a circuit substrate having first and second main surfaces, and The step of laminating the first resin composition layer and the first main surface of the circuit board

(II) A second resin sheet including a second support and a second resin composition layer bonded to the second support on the second main surface of the circuit board Sheet, and a step of laminating so that the second resin composition layer is bonded to the second main surface of the circuit board

(III) A step of curing the first and second resin composition layers to form the first and second solder resist layers

-Step (I)-

In step (I), a first resin including a first support and a first resin composition layer bonded to the first support is attached to a first main surface of a circuit substrate having first and second main surfaces. The sheet is laminated so that the first resin composition layer is bonded to the first main surface of the circuit board.

In the step (I), the first resin sheet used is as described in the above [Resin sheet group for solder resist layer of printed wiring board].

In the present invention, the "circuit board" refers to a substrate on which a solder resist layer is formed on both sides when a printed wiring board is manufactured. 2 Both sides of the main surface are provided with a patterned circuit wiring board. The layer configuration including the number of layers of circuit wiring is not particularly limited, and may be appropriately determined depending on the desired characteristics of the printed wiring board.

The thickness of the circuit board is not particularly limited when a printed wiring board that satisfies the above conditions (1) and (2) can be obtained. The thickness is preferably 240 μm or less, more preferably 220 μm or less, and still more preferably 200 μm or less. According to the present invention, even when a thinner circuit board is used, warping of the printed wiring board in the mounting step can be suppressed. For example, when using a circuit board with a thickness of 190 μm or less, 180 μm or less, 170 μm or less, 160 μm or less, 150 μm or less, 140 μm or less, 130 μm or less, 120 μm or less, 110 μm or less or 100 μm or less in thickness, it is possible to suppress Warping. The lower limit of the thickness of the circuit board is not particularly limited. From the viewpoint of improving the drawability during the production of the printed wiring board, it is preferably 10 μm or more, and more preferably 20 μm or more. In addition, the thickness of the circuit board refers to the thickness of the entire circuit board including the thickness of the surface circuit. Here, when the value obtained by excluding the thickness of the surface circuit from the thickness of the circuit substrate is t ₃ (μm), the above Z, t ₁ , t ₂ and t ₃ satisfy t ₁ + t ₂ + t ₃ = Z relationship.

The thickness of the surface circuit of the circuit board is not particularly limited. From the viewpoint of reducing the thickness of the printed wiring board, it is preferably 40 μm or less, more preferably 30 μm or less, still more preferably 25 μm or less, and still more preferably 20 μm. Below, 18 μm or less, 16 μm or less, 14 μm or less, 12 μm or less, or 10 μm or less. The lower limit of the thickness of the surface circuit is not particularly limited, and it may be generally 1 μm or more, 3 μm or more, and 5 μm or more.

The thermal expansion coefficient of the circuit board is preferably 16 ppm / ° C or less, more preferably 14 ppm / ° C or less, and even more preferably 12 ppm / ° C or less from the viewpoint of suppressing the occurrence of circuit distortion or cracks. Although the lower limit of the thermal expansion coefficient of the circuit board also varies depending on the composition of the resin composition used in the formation of the solder resist layer, it is preferably -2 ppm / ° C or more, more preferably 0 ppm / ° C or more, and even more preferably 4 ppm / ° C. the above. In the present invention, the thermal expansion coefficient of the circuit substrate is a linear thermal expansion coefficient in the plane direction of 25 to 150 ° C. obtained by thermomechanical analysis (TMA) by a tensile weighting method. Examples of thermo-mechanical analysis devices that can be used for measuring the linear thermal expansion coefficient of circuit boards For example, "Thermo Plus TMA8310" manufactured by Rigaku and "TMA-SS6100" manufactured by Seiko Instruments.

The flexural modulus of the circuit board is not particularly limited. In the present invention, it is possible to suppress warpage in the mounting step regardless of the bending elasticity of the circuit board.

The lamination of the circuit board and the first resin sheet can be performed, for example, by heating and pressing the first resin sheet onto the circuit board from the first support side. As a member for heating and pressing the first resin sheet onto a circuit board (hereinafter, also referred to as a "heating and pressing member"), for example, a heated metal plate (SUS mirror plate, etc.) or a metal roller (SUS roller). In addition, the first resin sheet is not directly pressed against the first resin sheet, but is caused by the unevenness of the circuit on the surface of the circuit board. The first resin sheet is sufficiently followed by an elastic material such as heat-resistant rubber. Pressure is better.

The heating and pressing temperature is preferably in the range of 80 ° C to 160 ° C, more preferably in the range of 100 ° C to 140 ° C, and the heating and pressing pressure is preferably in the range of 0.098MPa to 1.77MPa and more preferably in the range of 0.29MPa to 1.47MPa The heating and pressing time is preferably in the range of 20 seconds to 400 seconds, and more preferably 30 seconds to 300 seconds. The lamination is preferably carried out under a reduced pressure of a pressure of 26.7 hPa or less.

Lamination can be performed by a commercially available vacuum laminator. Commercially available vacuum laminators include, for example, a vacuum pressurized laminator manufactured by Nagaku Seisakusho, a vacuum applicator made by Nichigo-Morton, and the like.

After lamination, at atmospheric pressure (atmospheric pressure), for example, by The heat-pressing member is pressed from the first support side to smooth the first laminated sheet after lamination. The pressing conditions for the smoothing treatment may be the same conditions as those for the heat-pressing conditions of the laminate. The smoothing process can be performed by a commercially available laminator. The lamination and smoothing treatment can also be performed continuously using the above-mentioned commercially available vacuum laminator.

-Step (II)-

In step (II), the second resin sheet including the second support and the second resin composition layer bonded to the second support is attached to the second main surface of the circuit board, and the second resin composition layer is used. Lamination is performed so as to be bonded to the second main surface of the circuit board.

The second resin sheet used in step (II) is as described in the above [Resin sheet group for solder resist layer of printed wiring board].

The lamination of the circuit board and the second resin sheet can be performed in the same manner as in step (I). After the circuit substrate and the second resin sheet are laminated, the smoothing process described in step (I) may be performed on the second resin sheet.

Step (I) and step (II) can be performed simultaneously using a commercially available vacuum laminator.

The first and second supports can be removed before step (III). Alternatively, the first and second supports may be removed after step (III) (when using a thermosetting resin composition layer), or may be removed between steps (III) (using a photocurable resin composition layer) Case).

-Step (III)-

In step (III), the first and second resin composition layers are hardened to form the first and second solder resist layers.

The hardening conditions of the resin composition layer are not particularly limited, and the conditions generally used when forming a solder resist layer of a printed wiring board may be used.

When at least one of the first and second resin composition layers is a thermosetting resin composition layer, step (III) includes thermally curing the thermosetting resin composition layer to form a solder resist layer.

The conditions for heat curing vary depending on the composition of the resin composition used in the thermosetting resin composition layer, and the curing temperature is in the range of 120 ° C to 240 ° C (preferably in the range of 150 ° C to 210 ° C, more preferably) A range of 170 ° C to 190 ° C) and a curing time in a range of 5 minutes to 150 minutes (preferably 10 minutes to 120 minutes, and more preferably 15 minutes to 90 minutes). The heat curing is preferably performed at atmospheric pressure (under normal pressure). In addition, heat curing may be performed a plurality of times. For example, step (III) may be performed a plurality of times before step (IV) described later, step (III) may be performed more than once before step (IV) described later, and then after step (IV) and (V), 1 may be performed. More than two times of heat curing. When the heat curing is performed n times, the "elasticity after hardening" refers to the elastic modulus after n times of heat curing.

When at least one of the first and second resin composition layers is a photocurable resin composition layer, step (III) includes exposing, developing, and baking the photocurable resin composition layer to form a solder resist layer.

The exposure of the photocurable resin composition layer can be performed by irradiating a predetermined portion of the photocurable resin composition layer with active light using a mask pattern, for example. Thereby, the photocurable resin composition of an irradiation part can be photocured. As for the active light, for example, ultraviolet rays, visible rays, electron rays, X-rays, and the like are particularly preferred. The amount of ultraviolet radiation is not particularly limited, and may be a range generally used when forming a solder resist layer using a photocurable resin composition, but it is preferably 10 mJ / cm ² to 1000 mJ / cm ² . When a support is present on the photocurable resin composition layer, it can be exposed from the support.

The developing system uses a developing solution, and can also be carried out by removing the uncured portion (unexposed portion). Thereby, a desired pattern can be formed. If a support is present on the photocurable resin composition layer, the support may be removed and then developed. As the developing solution, an alkaline developing solution is preferred, and examples thereof include an aqueous solution of sodium carbonate and an aqueous solution of sodium hydroxide. As the development method, for example, spraying, shaking dipping, brushing, scraping, and the like can be mentioned.

The baking conditions vary depending on the composition of the resin composition used in the photocurable resin composition layer, but the baking temperature may be in the range of 120 ° C to 240 ° C (preferably in the range of 150 ° C to 210 ° C, The range is more preferably 170 ° C to 190 ° C), and the baking time may be in the range of 5 minutes to 150 minutes (preferably 10 minutes to 120 minutes, and more preferably 15 minutes to 90 minutes). The baking is preferably performed at atmospheric pressure (under normal pressure). In addition, baking may be performed multiple times. When the baking is performed n times, the aforementioned "elasticity rate after hardening" refers to the elasticity rate after n times of baking.

When one side of the first and second resin composition layers is a thermosetting resin composition layer and the other side is a photocurable resin composition layer, The curing of the curable resin composition layer can be performed simultaneously with the thermal curing of the thermosetting resin composition layer.

By performing the steps (I) to (III) using the resin sheet group of the present invention, a printed wiring board that satisfies the conditions (1), (2), and (3) described above can be easily manufactured.

-Other steps-

The method for manufacturing a printed wiring board may further include (IV) a step of forming an opening, and (V) a step of electroless copper plating. These steps (IV) and (V) are used for the manufacture of printed wiring boards, and can be carried out according to various methods known to those skilled in the art. In addition, when the first and second supports are peeled after step (III) (in the case of using a thermosetting resin composition layer), the peeling of the first and second supports can be performed in steps (III) and steps. (IV), between step (IV) and step (V), or after step (V).

Step (IV) is a step of forming an opening. Thereby, an opening can be formed in the solder resist layer formed using the thermosetting resin composition. In addition, if necessary, step (IV) may be performed in order to form an opening in the solder resist layer formed using the photocurable resin composition. Step (IV) is performed according to the composition of the resin composition constituting the solder resist layer, and can be performed using, for example, drilling, laser, or plasma. The size or shape of the opening is appropriately determined depending on the design of the component mounting substrate (also referred to as "semiconductor device").

When the opening is formed by a laser, Examples include carbon dioxide gas lasers, YAG lasers, excimer lasers, and the like. Among them, in terms of processing speed and cost, carbon dioxide gas laser is preferred.

Step (V) is a step of electroless copper plating. In the step (IV), a resin residue (smudge) is generally attached inside the formed opening. This stain may cause a poor electrical connection. Therefore, in step (V), a stain removal treatment (electroless copper plating treatment) is performed.

The electroless copper plating treatment can be implemented by combining dry electroless copper plating treatment, wet electroless copper plating treatment, or a combination thereof.

As for the dry-type electroless copper treatment, for example, electroless copper treatment using a plasma can be mentioned. The electroless copper electroplating treatment system using a plasma can be implemented using a commercially available electroless copper electroplating treatment apparatus. Among the commercially available plasma electroless copper treatment devices, more preferable examples of the manufacturing use of printed wiring boards include microwave plasma devices manufactured by Nissin and products manufactured by Sekisui Chemical Industry Co., Ltd. Normal piezoelectric slurry etching equipment.

For the wet electroless copper plating treatment, for example, an electroless copper plating treatment using an oxidizing agent solution can be mentioned. When using an oxidant solution to perform electroless copper plating, it is preferable to perform a swelling treatment with a swelling solution, an oxidation treatment with an oxidant solution, and a neutralization treatment in order. As for the swelling liquid, for example, "Swelling Dip Securiganth P" and "Swelling Dip Securiganth SBU" manufactured by ATOTECH JAPAN (stock) are mentioned. The swelling treatment is preferably performed by heating the substrate on which the openings are formed to 60 ° C to 80 ° C, and immersing the substrate in a swelling liquid for 5 to 10 minutes. Oxidant As the solution, an alkaline aqueous solution of permanganic acid is preferable, and for example, a solution in which potassium permanganate and sodium permanganate are dissolved in an aqueous solution of sodium hydroxide. The oxidation treatment using the oxidant solution is preferably performed by immersing the substrate after swelling treatment in an oxidant solution heated to 60 ° C to 80 ° C for 10 minutes to 30 minutes. Examples of commercially available products of the alkaline permanganic acid aqueous solution include "Concentrate Compact CP" and "Dosing Solution Securiganth P" manufactured by ATOTECH Japan. The neutralization treatment with the neutralization solution is preferably performed by immersing the substrate after the oxidation treatment in a neutralization solution at 30 ° C to 50 ° C for 3 minutes to 10 minutes. As the neutralizing solution, an acidic aqueous solution is preferred. For commercially available products, for example, "Reduction Solution Securiganth P" manufactured by ATOTECH JAPAN is available.

When the combination of dry electroless copper plating and wet electroless copper plating is implemented, the dry electroless copper plating may be performed first, or the wet electroless copper plating may be performed first.

Although the method of manufacturing a printed wiring board using the resin sheet set of the present invention has been described above, as long as a printed wiring board that satisfies the conditions (1), (2), and (3) described above can be obtained, the printing of the present invention is manufactured. The method of the wiring board is not particularly limited. For example, a printed circuit board can be manufactured by applying a coating of a resin composition to both surfaces of a circuit board, drying and curing the same.

[Semiconductor device]

A semiconductor device can be manufactured using the printed wiring board of the present invention. this invention Even if the printed wiring board is thin, it can suppress warpage during the mounting process of parts with high solder reflow temperature, which is helpful to reduce problems such as circuit distortion or poor contact of parts.

Examples of the semiconductor device include various semiconductor devices such as power supply gas products (for example, computers, mobile phones, digital cameras, and televisions) and vehicles (for example, motorcycles, automobiles, trams, ships, and airplanes).

[Example]

Hereinafter, the present invention will be specifically described by examples, but the present invention is not limited to these examples. In addition, "part" and "%" in the following respectively mean "mass part" and "mass%" unless otherwise clearly indicated.

First, various measurement methods and evaluation methods will be described.

[Preparation of evaluation substrate] (1) Preparation of circuit board

A glass cloth substrate epoxy resin two-area laminate on which circuits were formed on both sides was etched with a micro etchant ("CZ8100" made by MEC (strand)) for 1 µm, and a surface circuit was roughened to prepare a circuit board. For glass cloth substrate epoxy resin two-area laminates with circuits formed on both sides, Examples 1, 2 and 4 and Comparative Examples 1 and 2 use "HL832NSF-LCA" (size 100mm x 150mm) manufactured by Mitsubishi Gas Chemical Co., Ltd. , Thickness 100μm, The thermal expansion coefficient is 4 ppm / ° C, the flexural modulus is 34 GPa, and the thickness of the surface copper circuit is 16 μm.) Example 3 and Comparative Examples 3 and 4 use "E679FGR" (size 100 mm x 150 mm, thickness 200 μm, thermal expansion) manufactured by Hitachi Chemical Industries, Ltd. The rate was 14 ppm / K, the flexural modulus was 26 GPa, and the thickness of the surface copper circuit was 16 μm (Example 3 and Comparative Example 3), 8 μm (Comparative Example 4)).

(2) Lamination of resin sheet

The circuit board obtained in the above (1) is a resin vacuum sheet lamination machine (2 stage build-up laminator made by Nichigo-Morton Co., Ltd.) in the following production example. CVP700 ") and the resin composition layer and the circuit substrate are bonded to each other on both sides of the circuit substrate. After the laminate was decompressed for 30 seconds and the air pressure was 13 hPa or less, it was pressed at 100 ° C and a pressure of 0.74 MPa for 30 seconds. Next, a smoothing treatment was performed by hot pressing under normal pressure at 100 ° C. and a pressure of 0.5 MPa for 60 seconds.

In addition, the combination of the first and second resin sheets on the two area layers of the circuit board is shown in Table 1.

Next, as described below, the resin composition layer is cured to form a solder resist layer.

-When using resin sheets 1 and 2 containing a thermosetting resin composition layer-(3) Thermal curing of the resin composition layer

The support was peeled from the substrate obtained in the above (2). Then, at 180 The resin composition layer was thermally hardened at a temperature of 30 ° C for 30 minutes to form a solder resist layer.

(4) Formation of openings

Using a CO ₂ laser processing machine ("ML605GTWIII-5200U" manufactured by Mitsubishi Electric Corporation), circular holes having an opening diameter of 60 μm were formed under the following condition 1 and circular holes having an opening diameter of 500 μm were formed under the following condition 2.

Condition 1: mask diameter 0.9mm, pulse width 19μs, energy 0.24mJ, number of shots 2, pulse intermittent mode

Condition 2: Mask diameter 10mm, pulse width 15μs, energy 18mJ, number of shots 4, pulse intermittent mode

(5) Electroless copper treatment

After the openings were formed, the circuit board was immersed in a swelling liquid ("Swelling Dip Securiganth P" manufactured by ATOTECH JAPAN Co., Ltd., an aqueous solution containing diethylene glycol monobutyl ether and sodium hydroxide) at 60 ° C for 5 minutes, and immersed In an oxidant solution ("Concentrate Compact CP" manufactured by ATOTECH JAPAN), KMnO ₄ : 60 g / L, NaOH: 40 g / L aqueous solution at 80 ° C for 10 minutes, and finally a neutralizing solution (ATOTECH JAPAN (stock) " Reduction Solution Securiganth P ", aqueous hydroxylamine sulfate solution) at 40 ° C for 5 minutes. Then, it dried at 100 degreeC for 30 minutes, and was made to heat-harden further at 180 degreeC, and the evaluation board | substrate was produced.

-When using resin sheets 3, 4 and 5 containing a photocurable resin composition layer- (3 ') Exposure, development, and baking of the resin composition layer

The substrate obtained in (2) above was allowed to stand at room temperature for 1 hour. Then, using a mask pattern, 100 mJ / cm ² of ultraviolet light was exposed from the support in such a manner that circular holes having an opening diameter of 60 μm and 500 μm can be formed. The exposure was performed using a pattern forming device ("UX-2240" manufactured by USHIO Electric Co., Ltd.). Then, it stood still at room temperature for 30 minutes, and the support was peeled.

With respect to the obtained substrate, a developing solution (a 2% by mass sodium hydroxide aqueous solution at 30 ° C) was sprayed on the entire surface of the resin composition layer at a spray pressure of 0.2 MPa for 40 seconds for development. In Comparative Example 2 using the resin sheet 4, a 30 ° C, 1% by mass sodium carbonate aqueous solution was used for the developing solution.

After development, it was dried at 80 ° C for 30 minutes, and then baked at 180 ° C for 90 minutes to obtain an evaluation substrate.

[Preparation of hardened material for evaluation]

The hardened | cured material for evaluation was prepared by the following procedure.

-When using thermosetting resin composition layer-containing resin sheets 1 and 2-

The resin composition layers of the resin sheets 1 and 2 were contacted with the release surface of a PET film with a release layer ("PET501010" manufactured by LINTEC Corporation; hereinafter also referred to as "evaluation support"). Placed using a vacuum laminator ("VP160" manufactured by Nichigo-Morton Co., Ltd.) Build up. The lamination conditions were a vacuum for 20 seconds, a pressing temperature of 80 ° C, a pressing pressure of 0.2 MPa, and a pressing time of 20 seconds.

After the support from the resin sheet was peeled from the obtained laminate, the resin composition layer was thermally cured under a curing condition of 180 ° C. for 90 minutes. Then, the support for evaluation was peeled, and the hardened | cured material for evaluation was obtained.

-When using resin sheets 3, 4 and 5 containing a photocurable resin composition layer-

The resin composition layers of the resin sheets 3, 4 and 5 were implemented in the same manner as in the above-mentioned [Preparation of hardened material for evaluation 1], and laminated on a PET film with a release layer ("PET501010" manufactured by LINTEC Corporation); also called "Evaluation support").

After the obtained laminated body was allowed to stand at room temperature for 1 hour, the resin composition layer was exposed to ultraviolet rays of 100 mJ / cm ² from the support. After peeling off the support from the resin sheet, the resin composition layer was treated under baking conditions of 80 ° C, 30 minutes, and 180 ° C, 90 minutes. Then, the support for evaluation was peeled, and the hardened | cured material for evaluation was obtained.

<Evaluation of warpage>

First, the substrate for evaluation was passed through a reflow device ("HAS-6116" manufactured by Japan Antum Corporation) at a solder reflow temperature with a peak temperature of 260 ° C (the reflow temperature curve is based on IPC / JEDEC J-STD-020C). Next, a shadow moire device ("TherMoire AXP" by Akrometrix) was used to comply with IPC / JEDEC J-STD-020C The reflow temperature curve based on (peak temperature: 260 ° C) was used to heat the lower surface of the evaluation substrate, and based on the grid lines arranged on the upper surface of the evaluation substrate, the displacement at a 25 mm angle in the center of the evaluation substrate was measured.

The difference between the maximum height and the minimum height of the obtained displacement data is “×” for 50 μm or more in the entire temperature range, and “○” for less than 50 μm.

<Measurement of elasticity>

The hardened body for evaluation was cut out into a dumbbell shape to obtain a test piece. This test piece was measured for tensile strength using a tensile tester "RTC-1250A" manufactured by ORIENTEC Corporation, and the elastic modulus at 23 ° C and 200 ° C was determined. The measurement was performed in accordance with JIS K7127.

<Measurement of glass transition point temperature (Tg)>

The cured product for evaluation was cut into a test piece having a width of 5 mm and a length of 15 mm. A thermomechanical analysis device ("TMA-SS6100" manufactured by Seiko Instruments) was used for this test piece, and a thermomechanical analysis by a tensile weight method was performed. Specifically, after the test piece was installed in the aforementioned device, the measurement was performed twice under a measurement condition of a load of 1 g and a temperature increase rate of 5 ° C./min. In the second measurement, the glass transition point temperature Tg (° C) was calculated from the point where the slope of the dimensional change signal changed.

The resin sheets 1, 2, 3, 4, and 5 used in the examples and comparative examples were produced by the following procedure.

<Production Example 1> Production of Resin Sheet 1

12 parts of bisphenol A epoxy resin ("jER828EL" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 185), naphthalene epoxy resin ("HP4032SS" manufactured by DIC (equity), about 144 epoxy equivalent) 3 Parts, bixylenol type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent about 185) 6 parts, biphenyl type epoxy resin ("NC3000H" manufactured by Nippon Kayaku Co., Ltd., epoxy resin Approximately 288) 25 parts, 10 parts of phenoxy resin ("YX6954BH30" manufactured by Mitsubishi Chemical Corporation), 30% by mass of MEK and cyclohexanone in a solid content of 10 parts), dissolved in the solvent petroleum brain 15 while stirring The portion is heated to dissolve. After cooling to room temperature, 20 parts of a phenol novolac hardener ("LA-7054" manufactured by DIC Corporation), a hydroxyl equivalent of 125, and a 60% solids MEK solution were mixed therein, and naphthalene was mixed therein. 10 parts of phenolic hardener ("SN485" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., hydroxyl equivalent 215, MEK solution with 60% solids content), hardening accelerator (4-dimethylaminopyridine (DMAP), solid form 0.4 parts by mass of 5% by weight of MEK solution), flame retardant ("HCA-HQ" manufactured by Sanko Co., Ltd., 10- (2,5-dihydroxyphenyl) -10-hydro-9-oxa-10- Phosphaphenanthrene-10-oxide, average particle size 2 μm) 3 parts, spherical silicon oxide (average particle size 1 μm, ( ) 240 parts of "SOC4" manufactured by Admatechs, carbon content per unit surface area of 0.47 mg / m ² ), 240 parts, and uniformly dispersed with a high-speed rotary mixer to prepare a resin coating 1.

For the support, a PET film with a thickness of 38 μm is prepared (Toray (shares) system "NS80A"). On the smooth surface of the support, a resin paint 1 was uniformly applied, the thickness of the dried resin composition layer was 16 μm, and the resin composition layer was dried at 80 ° C. to 120 ° C. (average 100 ° C.) for 3 minutes to prepare a resin sheet 1. .

<Preparation Example 2> Production of Resin Sheet 2

In addition to using 30 parts of a phenoxy resin ("YX6954BH30" manufactured by Mitsubishi Chemical Corporation) and a solid content of 30% by mass of MEK / cyclohexanone = 1/1 solution, the phenoxy resin (manufactured by Mitsubishi Chemical Corporation) YX6954BH30 ", 10 parts of MEK / cyclohexanone = 1/1 solution with a solid content of 30% by mass, using a ball surface-treated with an aminosilane-based coupling agent (" KBM573 "manufactured by Shin-Etsu Chemical Industry Co., Ltd.) 75 parts of silicon oxide (average particle size: 0.5 μm, (SOC2) manufactured by Admatechs, carbon content per unit surface area: 0.39 mg / m ² ) instead of an aminosilane-based coupling agent (made by Shin-Etsu Chemical Industry Co., Ltd.) "KBM573") 240 points of spherical silica (average particle size 1 μm, "SOC4" manufactured by Admatechs, 0.47 mg / m ² carbon per unit surface area), and Except for the point where the usage amount was changed from 15 parts to 10 parts, the rest was carried out in the same manner as in Production Example 1, a resin varnish 2 was prepared, and a resin sheet 2 was produced.

<Production Example 3) Production of Resin Sheet 3

100 parts of mixed xylenol-type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 185, non-volatile content 30% by mass MEK and cyclohexanone) 100 parts, the following synthesis example 1 73 parts of synthetic photocurable alkali-soluble resin A, photopolymerization initiator ("OXE-02" made by BASF JAPAN), ethyl ketone, 1- [9-ethyl-6- (2-methylbenzene Formamyl) -9H-carbazol-3-yl]-, 1- (0-ethylammonium oxime), 18 parts of non-volatile matter in 10% by mass of MEK solution) 18 parts, with an aminosilane-based coupling agent (Shin-Etsu Chemical 120 parts of spherical silicon oxide (average particle size 0.5 μm, (SOC2) manufactured by Admatechs, 0.39 mg / m ² carbon per unit surface area) surface treated by industrial ("KBM573") 20 parts of spherical silica (average particle size 0.1 μm, "UFP-30" manufactured by Denki Chemical Industry Co., Ltd.), surface-treated spherical silicon oxide based coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Industry Co., Ltd.), thinner (10 parts of `` DPHA '' manufactured by Nippon Kayaku Co., Ltd., dipentaerythritol hexaacrylate), hardening accelerator (2P4MZ manufactured by Shikoku Kasei Co., Ltd., 2-phenyl-4-methylimidazole, non-volatile components 2.5% by mass of MEK solution) 8.8 parts, rubber particles (GA 2.4 parts of "NT38 KASEI (AC3816N)", photosensitizer ("DETX-S", manufactured by Nippon Kayaku Co., Ltd.), 2, 4-diethylthioxanthone, non-volatile content 10 4.4% by mass of MEK solution) and 10 parts of diethylene glycol monoethyl ether acetal were uniformly dispersed with a high-speed rotary mixer to prepare a resin paint 3.

For the support, a PET film with a thickness of 16 μm ("R310-16B" manufactured by Mitsubishi Resin Co., Ltd.) was prepared. A resin varnish 3 was uniformly applied to the support so that the thickness of the dried resin composition layer was 23 μm, and dried at 75 ° C. to 120 ° C. (average 100 ° C.) for 5 minutes to prepare a resin sheet 3.

(Synthesis example 1) Synthesis of photocurable alkali-soluble resin A

In a 300 mL separable flask, measure 25 g of carbitol acetate and 50 g of 3-isocyanato-3,5,5-trimethylcyclohexyl isocyanate (manufactured by EVONIK) and heat at 40 ° C. Stir. In addition, 92.23 g of pentaerythritol triacrylate content ("M306" manufactured by Toa Kosei Co., Ltd.), 25 g of carbitol acetate, 0.45 g of dibutyltin dilaurate (manufactured by Tokyo Chemical Industry Co., Ltd.), and hydrogen were measured. 0.4 g of quinone (manufactured by Tokyo Chemical Industry Co., Ltd.) was mixed for 8 minutes with a blender ("Burnori Ritaro" manufactured by THINKY Co., Ltd.) to obtain a mixed solution 1. The obtained mixed liquid 1 was dropped into the above 300 mL separable flask using a dropping funnel over 1 hour. Thereafter, it was heated and stirred at 40 ° C. for 30 minutes to obtain 193.08 g of a reaction product of 3-isocyanato-3,5,5-trimethylcyclohexyl isocyanate and pentaerythritol triacrylate.

On the other hand, in a 500 mL separable flask, 132.26 g of carbitol acetate and 132.26 g of phenol novolac resin ("TD-2090" manufactured by DIC Corporation) were measured and stirred at 75 ° C until completely dissolved. . Next, 193.08 g of the above-mentioned reactant was added, and the mixture was heated and stirred at 85 ° C. until the isocyanate group disappeared. After cooling to 40 ° C, 3.11 g of ethanol (manufactured by Pure Chemical Co., Ltd.) was added, and the mixture was stirred for more than 2 hours to obtain a light-curable alkali-soluble resin A (acrylate-modified phenol resin) containing acrylate groups and phenolic hydroxyl groups. 46.71 g. The properties of the obtained photocurable alkali-soluble resin A are as follows.

． 60% by mass of solvent-soluble product

． 18% acrylic group

． Polystyrene-equivalent number average molecular weight (Mn): 4000

． Hydroxyl equivalent: 246

<Preparation Example 4> Production of Resin Sheet 4

80 parts of mixed xylenol-type epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 185, non-volatile content 30% by mass of MEK and cyclohexanone), acrylate group-containing Photocurable alkali-soluble resin with carboxyl group ("ZFR-1533H" manufactured by Nippon Kayaku Co., Ltd., bisphenol F-type epoxy acrylate, diethylene glycol monoethyl ether acetate solution with a solid content of 68%, Acid value 70mgKOH / g) 147 parts, photopolymerization initiator ("IRGACURE 907" made by BASF JAPAN), 2-methyl- [4- (methylthio) phenyl] morpholinyl-1- Acetone) 2.5 parts, spherical silicon oxide (average particle diameter 0.5 μm, (share) Admatechs SOC2), surface treated with amine-based silane coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.), per unit Surface area carbon content 0.39mg / m ² ) 80 parts, spherical silicon oxide (average particle size 0.1 μm, electrical chemical industry ( 20 parts of `` UFP-30 ''), thinner (`` DCPA '' made by Kyoeisha Chemical Industry Co., Ltd., tricyclodecane dimethanol diacrylate) 10 parts, hardening accelerator (Shikoku Chemical Co., Ltd. ) System "2 `` P4MZ '', 2.8 parts of 2-phenyl-4-methylimidazole, 2.5% by mass of non-volatile MEK solution), 2.4 parts of rubber particles (`` AC3816N '' manufactured by GANTSU KASEI Co., Ltd.), photosensitizer (Japanese version) 2 parts of "DETX-S" made by pharmaceutical (stock), 2,4-diethylthioxanthone, MEK solution with 10% by mass of non-volatile content), diethylene glycol monoethyl ether acetal ( Organic solvent) 3 parts, and uniformly dispersed with a high-speed rotary mixer to prepare a resin coating 4.

For the support, a PET film with a thickness of 16 μm ("R310-16B" manufactured by Mitsubishi Resin Co., Ltd.) was prepared. A resin varnish 4 was uniformly applied to the support so that the thickness of the dried resin composition layer was 23 μm, and dried at 75 ° C. to 120 ° C. (average 100 ° C.) for 5 minutes to prepare a resin sheet 4.

<Production Example 5> Production of Resin Sheet 5

Except that the resin paint 3 was uniformly applied so that the thickness of the dried resin composition layer was 8 μm, and the resin composition layer was dried at 75 to 120 ° C. (average 100 ° C.) for 2 minutes, the rest was implemented in the same manner as in Production Example 3. Manufacture resin sheet 5.

The obtained resin sheets 1 to 5 were combined as shown in Table 1 below to prepare resin sheet groups 1 to 6. In addition, the resin flakes 1 to 5 used in each resin flake group were prepared in accordance with the above-mentioned [Preparation of hardened material for evaluation], and measured the elastic modulus and glass transition temperature (Tg). The results are shown in Table 1 together.

<Example 1>

Using the resin sheet group 1, the evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Example 2>

Using the resin sheet group 2, the evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Example 3>

Using the resin sheet group 1, the evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Example 4>

Using the resin sheet group 3, a substrate for evaluation was obtained in accordance with the above [Preparation of the substrate for evaluation]. The evaluation results are shown in Table 2.

<Comparative example 1>

Using the resin sheet group 4, the evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Comparative example 2>

Using the resin sheet group 5, an evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Comparative example 3>

Using the resin sheet group 4, the evaluation substrate was obtained in accordance with the above-mentioned [Preparation of the evaluation substrate]. The evaluation results are shown in Table 2.

<Comparative Example 4>

Using the resin sheet group 6, the substrate for evaluation was obtained in accordance with the above [preparation of the substrate for evaluation]. The evaluation results are shown in Table 2.

Claims (10)

A printed wiring board is a printed wiring board including first and second solder resist layers, wherein the first solder resist layer includes a resin composition, and the elastic modulus (23 ° C) G ₁ (GPa) of the composition after hardening is 6 or more, the thickness of the first solder resist layer is t ₁ (μm), the thickness of the second solder resist layer is t ₂ (μm), and the elastic modulus (23 ° C) after hardening is G ₂ (GPa), and When the thickness of the printed wiring board is Z (μm), the following conditions (1) to (3) are satisfied: (1) Z ≦ 250; (2) (t ₁ + t ₂ ) /Z≧0.1; and (3 ) G ₁ × [t ₁ / (t ₁ + t ₂ )] + G ₂ × [t ₂ / (t ₁ + t ₂ )] ≧ 6. The printed wiring board according to claim 1, wherein the glass transition temperature (Tg) after the first solder resist layer is cured is 150 ° C or higher. The printed wiring board according to claim 1, wherein the first solder resist layer is formed by curing a resin composition having an inorganic filler content of 60% by mass or more. The printed wiring board according to claim 1, wherein the condition (2) is 0.1 ≦ (t ₁ + t ₂ ) /Z≦0.5. The printed wiring board according to claim 1, wherein G ₂ is 6 or more. The printed wiring board according to claim 1, wherein the second solder resist layer contains a resin composition, and the elasticity (23 ° C) of the composition after hardening It is 6 or more. The printed wiring board according to claim 1, wherein the elastic modulus (200 ° C) after the hardening of the first solder resist layer is G ₁ ′ (GPa), and the elastic modulus after the hardening of the second solder resist layer ( When 200 ° C) is G ₂ ′ (GPa), the following condition (4) is further satisfied: (4) G ₁ ′ × [t ₁ / (t ₁ + t ₂ )] + G ₂ ′ × [t ₂ / ( t ₁ + t ₂ )] ≧ 0.2. A semiconductor device including the printed wiring board according to any one of claims 1 to 7. A resin sheet group is a resin sheet group for a solder resist layer of a printed wiring board. The resin sheet group includes a first resin sheet having a first support and a first resin composition layer bonded to the first support. Elasticity (23 ° C) of the second resin sheet formed from the second resin sheet having the second support and the second resin composition layer bonded to the second support, and the resin composition constituting the first resin composition layer after curing. G ₁ (GPa) is 6 or more, the thickness of the first resin composition layer is t _1p (μm), the thickness of the second resin composition layer is t _2p (μm), and the elastic modulus after curing (23 ° C) When G ₂ (GPa) and the thickness of the printed wiring board is Z (μm), the following conditions (1 ′) to (3 ′) are satisfied: (1 ′) Z ≦ 250; (2 ′) (t _1p + t _2p ) /Z≧0.1; and (3 ′) G ₁ × [t _1p / (t _1p + t _2p )] + G ₂ × [t _2p / (t _1p + t _2p )] ≧ 6. The resin sheet group according to claim 9, wherein the resin composition constituting the second resin composition layer has an elastic modulus (23 ° C) after curing of 6 or more.