KR102547264B1 - Manufacturing method of resin laminate with wiring pattern - Google Patents

Abstract

In the manufacturing method of the resin laminate with a wiring pattern of the present invention, the copper layer is formed on the surface of the copper layer in a laminate of resin layers (1, 11) and copper layers (2, 12) containing polyvinyl acetal resin. The step of providing the etching resist layer 3 or the wiring pattern layer 14 so that the first openings 8 and 18 in which the layer is exposed are formed, and the copper layer exposed in the first opening is etched to copper and a step of exposing the surface on the copper layer side of the resin layer by removing it using an etchant containing substantially no chlorine.

Description

Manufacturing method of resin laminate with wiring pattern

The present invention relates to a method for manufacturing a resin laminate with a wiring pattern from a laminate of a copper layer and a resin layer containing polyvinyl acetal resin.

Conventionally, in a laminate having a transparent resin film and a metal layer such as copper laminated on the film, it is proposed to use an element having a metal electrode pattern obtained by subjecting the metal layer to photolithography and etching as a transparent heating panel or the like. there is. As one of the transparent resins, polyvinyl acetal resins such as polyvinyl butyral are known (for example, Patent Document 1).

On the other hand, as an etchant in the case of forming a copper wiring on a resin substrate by etching a copper layer laminated on a resin substrate, in many cases, an etchant containing chlorine such as cupric chloride is used (eg For example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2007-102002 Japanese Unexamined Patent Publication No. 2013-80735

However, transparency is increasingly required for transparent resins with circuits used in transparent heating panels and the like, and for this reason, it is required that the transparency of the transparent resin not be reduced due to discoloration or the like even in the etching of the copper layer during circuit formation. This is not an exception even when etching a laminate of a resin layer containing polyvinyl acetal resin and a copper layer.

The subject of this invention is providing the manufacturing method of the resin laminated body with a wiring pattern which can eliminate the fault which the prior art mentioned above has.

The present invention relates to an etching resist layer or a wiring pattern layer such that a first opening through which the copper layer is exposed is formed on the surface of a copper layer in a laminate of a resin layer containing a polyvinyl acetal resin and a copper layer. The process of preparing a

A step of exposing the surface of the resin layer on the copper layer side by removing the copper layer exposed in the first opening using an etchant having copper etching ability and substantially not containing chlorine. It is to provide the manufacturing method of the resin laminated body with a wiring pattern provided with.

1(a) to 1(e) are schematic diagrams showing circuit formation procedures in the subtractive method.
2(a) to 2(f) are schematic diagrams showing circuit formation procedures in the additive method.

The present invention will be described below based on its preferred embodiments. The manufacturing method of the resin laminate with a wiring pattern (hereinafter sometimes referred to as "the method of the present invention") of the present invention is a copper layer in a laminate of a resin layer containing polyvinyl acetal resin and a copper layer. A step of providing an etching resist layer or a wiring pattern layer so that a first opening through which the copper layer is exposed is formed on the surface (hereinafter also referred to as a "first step");

A step of exposing the surface of the resin layer on the copper layer side by removing the copper layer exposed in the first opening using an etchant having copper etching ability and substantially not containing chlorine. (hereinafter also referred to as "second process") is provided. In the present invention, "copper layer" refers to a layer made of pure copper or a copper alloy, and it is preferable from the viewpoints of conductivity, etching workability, etc. of the copper layer that the proportion of copper is typically 95% by mass or more. As a wiring pattern of the resin laminate with a wiring pattern, a wiring circuit made of copper is exemplified.

As described above, in the method of manufacturing a resin laminate with a wiring pattern when forming a circuit with a transparent resin substrate, while being able to prevent discoloration of the transparent resin has been required, the present inventors have developed a polyvinyl acetal resin. It has been found that when the copper layer in a laminate comprising a resin layer and a copper layer is etched with cupric chloride, the resin layer tends to turn yellow. Yellowing reduces the product value of a transparent heating panel formed by forming a circuit on a transparent resin substrate. The present inventors have found that this yellowing can be prevented by etching the copper layer with an etchant substantially free of chlorine.

Examples of circuit formation methods to which the method of the present invention is applied include a subtractive method, a semi-additive method, and a modified semi-additive method. In the case of the subtractive method, an etching resist layer is provided in the first step described above, and in the case of the semi-additive method and the modified semi-additive method, the wiring pattern layer is provided in the first step described above. In the following description, the semi-additive method and the modified semi-additive method are collectively referred to simply as the additive method in some cases.

First, the case where the method of the present invention is applied to circuit formation by the subtractive method will be described based on Figs. 1(a) to (e). On the other hand, since FIGS. 1 and 2 are typical, they do not show actual dimensional relationships.

In the subtractive method, a laminate 10 of a resin layer 1 containing polyvinyl acetal resin and a copper layer 2 shown in FIG. 1 is used. As this laminated body 10, the copper foil with a resin layer formed by laminating|stacking a resin layer on one surface of copper foil is mentioned. The thickness of the copper layer 2 is, for example, 1 μm or more and 30 μm or less in terms of handling properties of the laminate 10, ease of etching, and maintaining conductivity for using the electrode pattern as a heating element. It is preferable, and it is more preferable that it is 2 micrometers or more and 18 micrometers or less. The copper layer 2 is not particularly limited in the manufacturing method, and may be formed, for example, by either an electrolytic method, a rolling method, or a vapor phase method. In addition, when the thickness of a copper layer is as thin as 10 micrometers or less, you may use copper foil with a carrier for the improvement of handling property. Here, copper foil with a carrier has a structure in which a carrier, a release layer, and an ultra-thin copper foil are laminated in this order. Examples of the carrier include metals such as copper, iron, stainless steel, and aluminum, alloys containing these metals as a main component, and heat-resistant resins such as polyester and engineering plastics, and are typically copper foil. The thickness of the carrier 15 is preferably 12 μm or more and 100 μm or less, and more preferably 15 μm or more and 80 μm or less, from the viewpoint of transportability and tear resistance during peeling. The peeling layer is used for the purpose of facilitating peeling of the ultra-thin copper foil and the carrier, and any of a known organic peeling layer and an inorganic peeling layer may be used. Examples of organic components used in the organic release layer include nitrogen-containing organic compounds, sulfur-containing organic compounds, carboxylic acids, and the like. Examples of the nitrogen-containing organic compound include a triazole compound and an imidazole compound, and among these, a triazole compound is preferred because of its easy releasability and stability. Examples of triazole compounds include 1,2,3-benzotriazole, carboxybenzotriazole, N',N'-bis(benzotriazolylmethyl)urea, 1H-1,2,4-triazole and 3-amino -1H-1,2,4-triazole etc. are mentioned. Examples of sulfur-containing organic compounds include mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazolethiol and the like. Examples of carboxylic acids include monocarboxylic acids, dicarboxylic acids, and the like. On the other hand, examples of the inorganic component used in the inorganic exfoliation layer include metals or alloys made of at least one of Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, etc., or/and oxides thereof. there is. The thickness of the release layer is typically 1 nm or more and 1 μm or less, preferably 5 nm or more and 500 nm or less. The peel strength between the release layer and the carrier is preferably 2 gf/cm or more and 50 gf/cm or less, more preferably 5 gf/cm or more and 30 gf/cm or less, still more preferably 10 gf/cm or more and 20 gf/cm or less.

The resin layer used as the transparent resin substrate that can be employed in the present invention is preferably composed of polyvinyl acetal resin. Polyvinyl acetal resin is a resin obtained by acetalizing polyvinyl alcohol with an aldehyde, and an aldehyde having 1 to 10 carbon atoms is generally used as an aldehyde used for acetalization. Specifically, for example, n-butylaldehyde, isobutylaldehyde, n-valeraldehyde, 2-ethylbutylaldehyde, n-hexylaldehyde, n-octylaldehyde, n-nonylaldehyde, n-decylaldehyde, formaldehyde , acetaldehyde, benzaldehyde, and the like. For example, as the polyvinyl acetal resin, polyvinyl butyral, which is a resin obtained by acetalizing polyvinyl alcohol with butyraldehyde, or polyvinyl formal, which is a resin obtained by acetalizing polyvinyl alcohol, with formaldehyde, is used. Among these, the use of polyvinyl butyral resin is preferable from the viewpoints of flexibility of the transparent base material, penetration impact resistance as an intermediate layer such as glass, lamination workability as an intermediate layer such as glass, color clearness, transparency, and the like.

When the resin layer 1 is used as a transparent substrate, the content of the polyvinyl acetal resin in the resin layer 1 is 50 mass from the viewpoints of maintaining the transparency of the transparent substrate, flexibility of the resin layer, and maintaining adhesion to the copper layer. % or more is typical. In the resin layer 1, in addition to polyvinyl acetal resin, for example, a plasticizer composed of hydroxyl group-containing compound and ester compound of carboxylic acid-containing compound, etc., antioxidant, ultraviolet absorber, silane coupling agent, adhesion of silicone compound, etc. A gender imparting agent and the like may be appropriately contained.

The resin layer 1 may be molded by any conventionally known molding method such as an extrusion molding method, a casting method, a coating method, or a combination thereof. In addition, the resin layer 1 may purchase and use a commercially available polyvinyl acetal resin film.

The thickness of the resin layer 1 varies depending on whether the laminate with a circuit obtained by the method of the present invention is used for a display element, a touch panel, or a heating wire for a window glass, but the handling properties of the laminate 10 are also Considering this, it is generally preferable that it is 30 μm or more and 3000 μm or less, and more preferably 100 μm or more and 1500 μm or less. Moreover, the surface of the resin layer 1 may be embossed for the purpose of removing bubbles at the time of joining an intermediate layer, such as glass.

In the case of manufacturing the laminate 10 by laminating the resin layer 1 and the copper layer 2, as in the steps of (a) and (b) of FIG. 1, the laminate 10 is a method by heat compression is available. A vacuum laminator, a vacuum press machine, etc. can be used as a heat press machine. The heating temperature is preferably 40°C or more and 120°C or less, more preferably 50°C or more and 90°C or less, and the pressing force is preferably 0.2 MPa or more and 10 MPa or less, and 0.5 MPa or more and 5 MPa or less. More preferably, the pressing time is preferably 30 seconds or more and 120 seconds or less. The fact that the resin layer 1 and the copper layer 2 in the laminate 10 are directly bonded without an adhesive layer intervenes maintains the transparency of the resin layer 1 when a laminate with a circuit is formed. It is preferable at the point where an effect is exhibited still higher. When the copper layer in copper foil with a carrier is laminated|stacked with the resin layer 1 by the said method, a carrier is mechanically peeled after lamination|stacking.

As shown in FIG. 1(c), in the subtractive method, in the layered body 10, the etching resist layer 3 is formed by forming the first opening 8 through which the copper layer 2 is exposed. It is provided on the surface of the opposite side to the resin layer (1) in the layer (2). The etching resist layer 3 forms the same image as the wiring pattern through processes such as application or lamination, followed by exposure and development The photoresist used for the construction method etc. are mentioned. Among these, it is preferable that the etching resist layer 3 consists of a photoresist from points, such as processing precision of a pattern and processing speed of pattern formation. In this case, a layer in which the entire surface of the upper surface of the copper layer 2 in the laminate 10 is made of a photoresist is provided, and then a portion of this layer to be a wiring pattern is exposed, further forming a wiring pattern. The etching resist layer 3 in which the 1st opening part 8 was formed is obtained by removing development other than a site|part. As the photoresist, either a negative type in which the exposed portion is cured or a positive type in which the exposed portion is dissolved conversely may be used. Specifically, acrylic resins such as esters of (meth)acrylic acid are preferably used. The thickness of the etching resist layer 3 is preferably 1 µm or more and 30 µm or less, and more preferably 3 µm or more and 25 µm or less, from the viewpoint of enhancing adhesion to the copper layer during etching.

In the second step, as shown in FIG. 1(d), using an etchant having copper etching ability and substantially containing no chlorine, in the first opening 8 of the etching resist layer 3 The exposed copper layer 2 is removed to expose the surface 1a of the resin layer 1 on the copper layer 2 side.

That the etchant is substantially free of chlorine means that the chlorine content in the etchant is 100 mg/L or less, and within this range, it is preferable in that prevention of yellowing of the resin layer of the present invention is not affected. More preferably, the content of chlorine in the etching solution is 50 mg/L or less, more preferably 10 mg/L or less, still more preferably 2 mg/L or less. The concentration of chlorine in the etching solution can be measured by a conventionally known method such as an electrode method or a DPD method (diethyl-p-phenylenediamine method).

Etching agents in the etchant having copper etching ability and substantially not containing chlorine include metal persulfate salts and ammonium persulfate salts, a mixed solution of sulfuric acid and hydrogen peroxide, a mixed solution of sulfuric acid and iron sulfate, and the like. In particular, when persulfate is used, the influence of the etching process on the shape of the etching resist layer 3 or the adhesion of the etching resist layer 3 to the copper layer 2 is suppressed, and the wiring pattern obtained after etching is improved. desirable because The present inventors speculate that the reason is that dissolution of the etching resist layer 3 is difficult to occur when persulfate is used. As persulfate, persulfuric acid is used in terms of preventing yellowing of the resin layer 1 and improving the effect of good formability of circuit patterns by etching, and preventing adsorption of metal components to the resin layer 1 during etching. Alkali metal salts are preferred. Among the alkali metal salts of persulfuric acid, sodium persulfate or potassium persulfate (sometimes referred to as sodium peroxodisulfate or potassium peroxodisulfate) is preferred in terms of availability and the like. These etching agents can be used 1 type or in combination of 2 or more types.

Water is used as a solvent for dissolving the etchant in the etchant, and an immersion method, a shower method, or the like can be appropriately employed. Persulfate is more preferably contained in a concentration of 50 g/L or more and 300 g/L or less in the etching solution from the viewpoint of stability of copper layer etching rate, prevention of imbalance reaction due to variation in agitation speed or shower pressure, etc. It is especially preferred that it is contained in a concentration of L or more and 200 g/L or less. The concentration of persulfate in the etchant can be measured using a back titration method.

The etchant may contain components other than the above-mentioned etchant within a range not impairing the effects of the present invention. Examples of such components include sulfuric acid, surfactants, alcohols, and antifoaming agents.

The temperature of the etchant at the time of etching is preferably 22 ° C. or more and 60 ° C. or less, and more preferably 25 ° C. or more and 50 ° C. or less from the viewpoint of securing the etching rate and maintaining the stability of the liquid components.

The etching time is appropriately adjusted depending on the relationship such as the thickness of the copper layer, the width of the resist opening, the finished size, and the etching rate of the etchant.

As an etching method, a known method such as a spray method and an immersion method can be employed. The method of the present invention exposes all or part of the resin layer 1 positioned within the first opening 8 of the etching resist layer 3.

Through the above process, the resin laminate 9 with a wiring pattern is obtained. After etching, the obtained etchant is washed with a cleaning liquid such as water. The cleaning liquid is preferably substantially free of chlorine. "Substantially not containing chlorine" refers specifically to the fact that the content of chlorine in the washing liquid is 100 mg/L or less. It is preferable that this chlorine content is 50 mg/L or less, and it is more preferable that it is 10 mg/L or less.

Next, when the etching resist layer 3 is not removed in the above etching step, the etching resist layer 3 may be removed as shown in FIG. 1(e) as an optional step. For removal of the etching resist layer 3, for example, a known photoresist layer exfoliating agent can be appropriately selected and used. The photoresist layer may be stripped and removed by spraying or dipping.

The manufacturing method of the resin laminated body with a wiring pattern of this invention is applicable not only to the subtractive method but also to the additive method. An example applied to the additive method will be described based on FIG. 2 .

In the first step in the case of the additive method, as shown in Figs. 2 (a) and (b), a laminate 110 having a copper layer 12 as a seed layer is used as a laminate of a resin layer and a copper layer. The seed layer is a layer serving as an electrode when a metal layer (wiring pattern layer 14 described later) is laminated on the surface by electroplating. As the resin layer 11, the same resin layer 1 as described in the case of the subtractive method is used. Formation of the seed layer includes an electroless plating method, a vapor phase film forming method, and a copper foil lamination method using a copper foil with a carrier. Among them, when formed by the electroless plating method, chlorine in the plating solution may discolor the resin layer 110. In addition, the method by the vapor phase film formation method may include a sputtering method or a vacuum deposition method. In the case of the method by the vapor phase film formation method, when the resin layer 1 is a polyvinyl acetal resin, the resin component is sublimated into the seed layer. Terminations may exist. From these points, the copper foil lamination method using copper foil with a carrier is most preferable in terms of preventing chlorine discoloration and preventing contamination by contamination in the seed layer. The thickness of the seed layer is preferably 0.2 μm or more and 5.0 μm or less, and more preferably 0.3 μm or more and 3.0 μm or less, from the viewpoint of ease of flash etching, which will be described later.

The copper foil with a carrier employed in the copper foil lamination method, the copper foil lamination conditions, and the like are the same as those of the subtractive method described above.

Subsequently, as shown in FIG. 2(c), the plating resist layer 13 is formed on the copper layer 12 in the laminate 110 so that the second opening 17 through which the copper layer 12 is exposed is formed. It is provided on the surface of the layer 12 opposite to the resin layer 11. The plating resist layer 13 is preferably made of photoresist. In this case, a layer in which the entire upper surface of the copper layer 12 in the laminate 110 is made of photoresist is provided, and then the wiring pattern is exposed to light, and the wiring pattern in the layer made of photoresist is further formed. Remove the symptoms of the affected area. Through this process, the plating resist layer 13 in which the second opening 17 is formed is obtained. The thickness of the plating resist layer 13 is preferably greater than the height of the wiring pattern layer 14 to be formed.

Subsequently, as shown in FIG. 2(d), a wiring pattern layer 14, which is a metal layer, is formed in the second opening 17 by an electrolytic plating method. As a constituent metal of the wiring pattern layer 14, copper is usually used. It is preferable that it is 100 mg/L or less, and, as for the chlorine concentration in the metal plating solution in the electrolytic plating method, it is more preferable that it is 50 mg/L or less. However, when electrolytic plating is performed in a state where the side opposite to the electrolytic plating surface of the resin layer is covered with a protective layer such as photoresist, the chlorine concentration in the metal plating solution is not necessarily low. The thickness of the wiring pattern layer 14 is usually 2.0 μm or more and 30.0 μm or less. Thereafter, by removing the plating resist layer 13 as shown in FIG. 2(e), the wiring pattern layer 14 having the first opening 18 through which the copper layer 12 is exposed is formed. For the removal of the plating resist layer 13, an aqueous solution of sodium hydroxide or a mixture of an alkanolamine, an organic solvent, and water can be used.

Subsequently, flash etching is performed as a second process. Specifically, as shown in FIG. 2(f), the copper layer 12 exposed in the first opening 18 is formed using an etchant having copper etching ability and substantially containing no chlorine. and remove it For this reason, the surface of the resin layer 11 on the copper layer 12 side is exposed.

As the etchant and the solvent in the etchant, the same ones as in the case of the subtractive method may be used.

As described above, as a resin laminate with a wiring pattern by the additive method, a laminate with a circuit 19 in which a circuit is formed on the resin layer 11 can be obtained.

Other points of the method of the present invention in the additive method are the same as in the case of the subtractive method.

In the element in which a copper circuit is formed on a resin layer containing a polyvinyl acetal resin obtained by the method for producing a resin laminate with a wiring pattern of the present invention obtained as described above, discoloration of the resin layer is effectively prevented. Therefore, the original clear color tone of the transparent resin layer is maintained, and in addition to being used in elements utilizing the transparency of the resin layer, for example, light emitting display elements such as traffic signals and road signs, and touch panels on the front surface of displays, It is preferably used as a heating wire for a window glass or a shop window in a building, or a heating wire for a window glass such as a windshield or rear window in a vehicle. The heat wire of the window glass is used as a defroster, defogger, etc., and is placed in the middle layer of custom glass, etc.

Example

Hereinafter, the present invention will be described in more detail by examples. However, the scope of the present invention is not limited to these examples. Unless otherwise specified, "%" means "% by mass".

[Example 1]

(Process 1)

The manufacturing method of the resin laminated body with a wiring pattern in the procedure of the subtractive method shown in FIG. 1 was evaluated.

As the resin layer 1, a commercially available polyvinyl butyral resin film (grade: Architecture Use, color: clear, thickness: 760 µm) to which a plasticizer (dihexyladipic acid: DHA) was blended was used. Copper foil with a carrier (carrier: copper foil with a thickness of 18 μm, release layer: carboxybenzotriazole, ultra-thin copper foil thickness: 5 μm) was laminated so that the ultra-thin copper foil was in contact with the resin film, and then the carrier was mechanically peeled off to produce a laminate 10 having the resin layer 1 and the copper layer 2. On this, a resist mask was formed using a photoresist (thickness: 5 μm). Then, after ultraviolet irradiation was performed using a photomask masking the portion forming the pattern to form a wiring pattern, development was performed using a sodium carbonate solution as a developing solution, and parts other than the wiring pattern portion were removed to form a copper layer ( 2) An etching resist layer 3 having an exposed first opening 8 was formed (line/space (L/S) of the wiring forming portion: 10 µm/2000 µm).

(Process 2)

An aqueous solution of sodium persulfate (concentration: 150 g/L) was used for the etching solution. The chlorine concentration in this etchant was 1 mg/L. Using this etchant (30°C), the laminate obtained in step 1 was immersed in an etching process under conditions of just etching in which the residue to the opening 8 was not clearly visible. After etching, the circuit was washed with water (chlorine concentration: 1 mg/L), then the resist was removed using a 5% sodium hydroxide aqueous solution, washed again with the above water and dried. The obtained laminated body sample with a circuit was created, and resin yellowing degree and resist adhesion at the time of etching were evaluated by the following method.

(resin yellowing degree)

Color difference meter: Using Suga Test Instruments Co., Ltd. "Colour Cute i" in accordance with JIS K 7373, using standard illuminant D ₆₅ , the yellowness YI in the X ₁₀ Y ₁₀ Z ₁₀ color system was determined by the following formula. A sample in which no copper foil was laminated was used as a blank, and the yellowness YI increase rate (%) of the blank and the sample after the etching treatment was determined. Based on the obtained increase rate, it was evaluated according to the following evaluation criteria. The results are shown in Table 1.

A: increase rate less than 0.3%

B: increase rate of 0.3% or more and less than 1.0%

C: increase rate of 1.0% or more and less than 3.0%

D: increase rate of 3.0% or more

YI=100(1.3013X ₁₀ -1.1498Z ₁₀ )/Y ₁₀

(Resist Adhesion during Etching)

For the defect rate of the pattern after etching, line/space (L/S): 50 wires were observed with a stereo microscope (200x) for a wiring pattern of 10 µm/2000 µm. In each wiring, the case where there was a crack in the pattern was determined to be defective, and the pattern defect rate (%) {(the number of wirings determined to be defective/50 wires observed)×100} was calculated. Based on this pattern defect rate, the resist adhesion during etching was evaluated according to the following criteria. The results are shown in Table 1.

A: Pattern defect rate less than 5%

B: pattern defect rate 5% or more and less than 10%

C: pattern defect rate of 10% or more and less than 20%

D: pattern defect rate of 20% or more

[Example 2]

A sulfuric acid/hydrogen peroxide aqueous etchant (Enfrate E-462 manufactured by Meltex Co., Ltd., sulfuric acid concentration: 70 g/L, hydrogen peroxide concentration: 10 g/L) was used. The chlorine concentration in this etchant was 0.5 mg/L. A laminate with a circuit was produced and evaluated in the same manner as in Example 1 except that this etchant was used. The results are shown in Table 1.

[Comparative Example 1]

Cupric chloride and hydrochloric acid were added to water and mixed to prepare an aqueous solution having a cupric chloride concentration of about 135 g/L and a hydrochloric acid concentration of 105 g/L (chlorine concentration: 102 g/L). A laminate with a circuit was produced and evaluated in the same manner as in Example 1, except that this aqueous solution was used as an etchant and the etching treatment temperature was 45°C. The results are shown in Table 1.

[Comparative Example 2]

A laminate with a circuit was produced and evaluated in the same manner as in Example 1, except that the undiluted solution of Process A (Meltex Co., Ltd., trade name) was used as an etchant, and the treatment temperature was 45°C. The results are shown in Table 1.

In the stock solution, the concentration of ammonia copper complex salt was 250 g/L (copper concentration was 11 g/L), the concentration of ammonia chloride was 150 g/L (99 g/L as chlorine concentration), and the concentration of ammonia was 50 g/L.

[Example 3]

In this Example, the manufacturing method of the resin laminated body with a wiring pattern in the sequence of the additive process shown in FIG. 2 was evaluated. A polyvinyl butyral resin film used in Example 1 was prepared as the resin layer 11, and the same copper foil with a carrier as that used in Example 1 was laminated on the surface except that the thickness of the ultra-thin copper layer was 2 μm. was peeled off to form a copper layer 12 as a seed layer having a thickness of 2 μm on the resin layer 11. A resist mask was formed on the copper layer 12 using a plating resist (thickness: 25 μm). Subsequently, after UV irradiation is performed using a photomask to form a wiring pattern, development is performed using a sodium carbonate solution as a developer, and the wiring pattern portion is removed to form a second opening 17 where the copper layer 12 is exposed A plating resist layer 13 having was formed. Next, a wiring pattern layer 14 having a thickness of 20 μm and a line/space = 10 μm/200 μm was formed in the opening of the plating resist layer by electrolytic copper plating. Next, the plating resist layer 13 is removed using an aqueous sodium hydroxide solution to form the first opening 18, and then an aqueous solution of sodium persulfate (concentration: 150 g/L) (chlorine concentration: 1 mg/L, temperature: 50°C) was etched. Etching treatment was performed until just etching by the immersion method. After etching, the laminate was washed with water (chlorine concentration: 1 mg/L) and dried. About the obtained laminated body with a circuit, the increase rate of resin yellowness was calculated|required by the said method, and it evaluated. The results are shown in Table 1. Table 1 shows resin yellowing and resist adhesion in four stages A to D, as well as numerical values of yellowness increase rate (%) and pattern defect rate (%), respectively.

As shown in Table 1, yellowing of the resin layer containing polyvinyl acetal resin was effectively suppressed by using the etchant of each Example containing substantially no chlorine, whereas each etchant using an etchant containing chlorine was effectively suppressed. It turns out that resin is yellowing by using the etchant of the comparative example. Further, in the subtractive method, it is found that the evaluation of adhesion (pattern goodness) at the time of etching is high when persulfate is used as an etchant.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the resin laminated body with a wiring pattern excellent in the yellowing prevention property of the resin layer containing polyvinyl acetal resin can be provided.

Claims (6)

An etching resist layer or wiring pattern such that a first opening portion through which the copper layer is exposed is formed on the surface of the copper layer in the laminate of the resin layer containing 50% by mass or more of polyvinyl acetal resin and the copper layer. A step of preparing a layer;
The surface of the resin layer on the copper layer side is exposed by removing the copper layer exposed in the first opening using an etchant having copper etching ability and substantially containing no chlorine, The manufacturing method of the resin laminated body with a wiring pattern provided with the process of forming a wiring pattern. According to claim 1,
The manufacturing method of the resin laminated body with a wiring pattern whose content of chlorine in the said etchant is 100 mg/L or less. According to claim 1,
As the laminate, a laminate having a seed layer as the copper layer is used,
A plating resist layer is provided on the copper layer in the laminate so that a second opening through which the copper layer is exposed is formed, and then a wiring pattern layer is formed in the second opening by an electrolytic plating method, and then the plating The manufacturing method of the resin laminated body with a wiring pattern in which the said wiring pattern layer is provided so that the said 1st opening part which exposed the said copper layer may be formed by removing the resist layer. According to any one of claims 1 to 3,
The manufacturing method of the resin laminated body with a wiring pattern in which the etching agent of the said etchant consists of a persulfate. According to any one of claims 1 to 3,
The manufacturing method of the resin laminated body with a wiring pattern in which the said polyvinyl acetal resin is polyvinyl butyral resin. According to any one of claims 1 to 3,
The manufacturing method of the resin laminated body with a wiring pattern using the copper foil with a resin layer formed by laminating the said resin layer on one surface of copper foil as said laminated body.

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