JPWO2015152380A1 - Copper foil with carrier, method for producing copper foil with carrier, copper-clad laminate obtained using copper foil with carrier, and method for producing printed wiring board - Google Patents

Abstract

An object is to provide a copper foil with a carrier that is less likely to be oxidized in the copper foil after the carrier is peeled off. To achieve this object, a carrier-attached copper foil laminated in the order of a carrier, a release layer and a copper foil, the brightness L * value of the peeled surface of the copper foil immediately after the carrier release of the carrier-attached copper foil, and the carrier release The difference between the brightness L * value of the peeled surface after leaving the copper foil after leaving it for 3 days in a constant temperature and humid atmosphere at a temperature of 25 ° C. and a humidity of 50% to 70% is within 1.5. Adopt copper foil.

Description

  The present invention relates to a copper foil with a carrier, a method for producing the copper foil with a carrier, a copper-clad laminate and a printed wiring board obtained using the copper foil with a carrier. In particular, the present invention relates to a carrier-attached copper foil that hardly oxidizes the surface of the copper foil after peeling off the carrier.

  In recent years, in the printed wiring board manufacturing field, with the miniaturization of wiring patterns, the foil thickness of copper foil tends to be reduced. However, when the foil thickness is reduced, the handleability of the copper foil is deteriorated. Therefore, conventionally, a copper foil with a carrier in which a metal foil having a predetermined thickness is used as a carrier and an ultrathin copper foil is laminated on the carrier via a release layer has been widely used.

  For example, Patent Document 1 states that “provides a copper foil with a carrier that can be peeled off after a lamination process on an insulating substrate while the ultrathin copper layer does not peel off from the carrier before the lamination process on the insulating substrate”. As an object, “comprising a copper foil carrier, an intermediate layer laminated on the copper foil carrier, and an ultrathin copper layer laminated on the intermediate layer, and the intermediate layer is formed of nickel on the copper foil carrier. , "Copper foil with carrier" constructed by laminating molybdenum, cobalt, or molybdenum-cobalt alloy in this order.

  Patent Document 2 states that “an electrolytic copper foil with a carrier foil having a bonding interface layer on the surface of the carrier foil, and an auxiliary metal layer and an electrolytic copper foil layer on the bonding interface layer. An electrolytic copper foil with a carrier foil provided with a bonding interface layer formed using an organic agent or a metal material on the smooth surface side is disclosed.

  And the copper foil with a carrier mentioned above is first laminated | stacked with a prepreg, resin, etc. in the manufacturing process of a printed wiring board, and is processed into a copper clad laminated board. And in the state which peeled the carrier of the copper foil with a carrier from the copper clad laminated board, it may be stored and transported until the subsequent laser drilling process and circuit formation process.

Japanese Patent No. 5228130 JP 2001-308477 A

  However, when the carrier is peeled from the copper clad laminate, the surface of the copper foil is exposed. The copper foil with a carrier disclosed in Patent Document 1 employs nickel and molybdenum, cobalt, or a molybdenum-cobalt alloy as an intermediate layer laminated between the copper foil carrier and the ultrathin copper layer. Therefore, when the ultrathin copper layer is exposed by peeling at the interface between the ultrathin copper layer and the intermediate layer, the ultrathin copper layer immediately contacts with the atmosphere and oxidation proceeds immediately. Therefore, when using the copper foil with a carrier of Patent Document 1 and storing and transporting the copper foil carrier in a peeled state, it is necessary to subject the surface of the ultrathin copper layer to rust prevention after the copper foil carrier is peeled off. is there.

  In addition, the electrolytic copper foil with a carrier foil disclosed in Patent Document 2 has an organic agent that forms a bonding interface layer on the surface layer of the auxiliary metal layer when the carrier foil is peeled from the electrolytic copper foil layer. This organic agent plays a role as a rust prevention layer of the electrolytic copper foil layer. However, the electrolytic copper foil with carrier foil disclosed in Patent Document 2 is difficult to separate the organic agent and the auxiliary metal uniformly in the same plane, so the rust prevention function varies, and after the carrier foil is peeled off The oxidation of the surface of the electrolytic copper foil proceeds locally.

  When the surface of the ultra-thin copper foil processed into the copper-clad laminate is oxidized, the hole diameter varies in the laser drilling process when wiring the ultra-thin copper foil. If the hole diameter varies, a hole diameter different from the required range is formed, resulting in a defective product. In addition, since the portion where the surface is oxidized is more easily etched than the portion which is not oxidized, the etching process during pattern formation also varies. If the etching process varies, the circuit width differs from the required range, resulting in a defective product. In particular, when the circuit is remarkably thinned, the possibility of disconnection increases.

  Therefore, this invention is providing the copper foil with a carrier with which an oxidation does not produce easily in copper foil after peeling a carrier.

  The present inventors have achieved the above-mentioned problems by adopting the carrier-attached copper foil described below.

Copper foil with carrier: The copper foil with carrier according to the present invention is a copper foil with carrier laminated in the order of a carrier, a release layer, and a copper foil, and the release surface of the copper foil immediately after carrier release of the copper foil with carrier. a lightness L ^* value of the difference between the lightness L ^* value of the release surface after leaving for 3 days under constant temperature humidified atmosphere of copper foil and the temperature 25 ° C. humidity of 50% to 70% after the carrier peeling 1.5 It is within.

Manufacturing method of copper foil with carrier: The manufacturing method of copper foil with carrier according to the present invention is a manufacturing method of the above-described copper foil with carrier, and includes the steps A, B, and C described below. And
A: A step of forming an inorganic release layer or an organic release layer as a release layer on the surface of the carrier.
B: The process of forming the metal dispersion layer containing an organic component as a peeling layer on the surface of the said inorganic peeling layer or the organic peeling layer.
C: A step of forming a copper foil on the surface of the metal dispersion layer.

Copper-clad laminate: The copper-clad laminate according to the present invention is obtained using the above-described copper foil with a carrier.

Printed wiring board: The printed wiring board according to the present invention is obtained using the above-described copper foil with a carrier.

  Since the copper foil with a carrier according to the present invention has an excellent anti-oxidation property on the surface of the copper foil after peeling the carrier, it is processed into a copper-clad laminate and then stored or transported in a state where the carrier is peeled off. Even if it is, oxidation of the copper foil surface hardly occurs. Therefore, even if the copper foil with a carrier according to the present invention is stored in the atmosphere for 3 days or more without peeling the carrier and subjecting the copper foil surface to a special rust prevention treatment, laser drilling or pattern formation is performed. Variation in etching process is small. Therefore, the copper foil with a carrier according to the present invention can form a hole diameter and a circuit width within a required range. Further, it is possible to avoid a possibility that the circuit is remarkably thinned and disconnection occurs.

  Hereinafter, embodiments of the copper foil with carrier and the method for producing the copper foil with carrier according to the present invention will be described.

<Copper foil with carrier>
The copper foil with a carrier according to the present invention is a lightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling of the copper foil with the carrier, and the copper foil after the carrier peeling at a temperature of 25 ° C. and a humidity of 50% to 70%. The difference between the lightness L ^* value of the peeled surface after being left for 3 days in a constant temperature and humid atmosphere is within 1.5. The peeling surface of copper foil here is the surface on the side where the carrier of copper foil is peeled off. Hereinafter, the surface of the copper foil carrier from which the carrier has been peeled is referred to as a peeled surface. And this copper foil with a carrier is equipped with the layer structure laminated | stacked in order of "carrier", "peeling layer", and "copper foil". Therefore, in the following, “lightness L ^* value”, “carrier”, “release layer”, and “copper foil” will be described in order.

Lightness L ^* Value: The copper foil with carrier according to the present invention adopts the lightness L ^* value by color difference measurement as an index of the antioxidant property of the copper foil after carrier peeling. The lightness L ^* value by color difference measurement represents a brighter color tone as the value increases, and represents a darker tone as the value decreases. When the peeling surface of the copper foil after carrier peeling is oxidized, the degree of black is high and the lightness L ^* value by color difference measurement is low. Therefore, the smaller the difference between the lightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling and the lightness L ^* value of the peeled surface of the copper foil after the carrier is left to stand, the copper foil after the carrier peeling. Means having excellent antioxidant properties.

Therefore, the inventors of the present invention described “the brightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling” and “the copper foil after the carrier peeling in a constant temperature humidified atmosphere at a temperature of 25 ° C. and a humidity of 50% to 70%. It was conceived that if the difference from the “lightness L ^* value of the peeled surface after being left for 3 days” is within 1.5, it can be determined that the copper foil after carrier peeling has excellent antioxidant properties. That is, if the difference between the lightness L ^* value of the peeled surface immediately after carrier peeling and the lightness L ^* value of the peeled surface after being left in a constant temperature and humidified atmosphere for 3 days is within 1.5, laser drilling performance, It can be determined that no oxidation progress has occurred which greatly affects the etching performance during pattern formation. The difference in the lightness L ^* value of the peeled surface of the copper foil before and after the carrier peeling is more preferably 1.0 or less, and further preferably 0.5 or less.

Next, in the copper foil with a carrier according to the present invention, the copper foil from which the carrier was peeled was allowed to stand for 3 days in a constant temperature and humid atmosphere having a temperature of 25 ° C. and a humidity of 50% to 70%, and then the copper foil was spaced at an interval of 10 cm. The standard deviation σ of the brightness L ^* value of the peeled surface of the copper foil measured at a plurality of locations is preferably 1 or less. The standard deviation σ of the lightness L ^* value of the peeled surface is more preferably 0.7, and further preferably 0.5. The copper foil with a carrier according to the present invention is produced by continuously producing copper on the surface of the carrier wound up in a roll shape by the production method, so that the winding direction and its There is a width direction perpendicular to the winding direction. Therefore, in the present invention, the standard deviation σ in the width direction is used in order to capture the variation in the brightness L ^* value of the peeled surface in the width direction of the copper foil after carrier peeling. This is because when the oxidation is locally progressing on the copper foil surface after the carrier peeling, the local variation of the lightness L ^* value in the color difference measurement becomes large. Therefore, since the copper foil with a carrier according to the present invention has a standard deviation σ of the lightness L ^* value of the peeled surface of the copper foil measured at a plurality of locations at intervals of 10 cm in the width direction, it is 1 or less. It can be judged that it has excellent antioxidant properties with little variation. Therefore, the copper foil with a carrier according to the present invention can reduce the variation in the hole diameter in the laser drilling process to the copper foil and the variation in the etching process at the time of pattern formation over the width direction.

Moreover, as for the copper foil with a carrier which concerns on this invention, it is preferable that the brightness L ^* value of the peeling surface of the said copper foil immediately after peeling a carrier is 50 or less. This is because, if the lightness L ^* value immediately after the carrier peeling is 50 or less, the laser processability is enhanced, and the variation in the lightness L ^* value caused by the standing time after the carrier peeling and the environmental change tends to be reduced. Therefore, by setting the lightness L ^* value immediately after the carrier peeling to 50 or less, a via having a uniform hole diameter can be formed by laser processing, and the uniformity within the same surface of the etching process during pattern formation can be improved. The lightness L ^* value immediately after the carrier peeling is more preferably 45 or less, still more preferably 43 or less, and particularly preferably 40 or less, from the viewpoint of reducing variations in the lightness L ^* value caused by subsequent standing time or environmental changes. Is preferred.

Carrier: In the present invention, the carrier is a material having a predetermined thickness in order to improve the handleability of the thin copper foil, and the material is not particularly limited. However, when the carrier is energized to form a copper foil layer of the carrier-attached copper foil by electrodeposition, for example, a carrier that can be energized such as an aluminum foil, a copper foil, or a resin film whose surface is metal-coated is used. It is preferable. Moreover, although the thickness of the said carrier is not limited, when using copper foil as a carrier, when handling property is considered, the thickness of 7 micrometers-210 micrometers is preferable. In order to expect a copper foil as a carrier to serve as a reinforcing material for preventing wrinkles, a thickness of at least 7 μm is required.

Release layer: In the present invention, the release layer is a layer that exists in a state of being sandwiched between the carrier and the copper foil, and enables the carrier to be peeled off. In the copper foil with a carrier according to the present invention, it is preferable that the release layer is either “an inorganic release layer using an inorganic component” or “an organic release layer using an organic component”. Hereinafter, it demonstrates in order.

  “Inorganic release layer using inorganic components” includes metals such as chromium, nickel, molybdenum, cobalt, iron, titanium, tungsten, phosphorus, zinc, tantalum, vanadium, alloys of these metals, or these The listed metal oxides or oxides of these listed metal alloys can be used. And it is preferable that the thickness of this inorganic peeling layer is 1 nm-1000 nm.

  The “organic release layer using an organic component” can stabilize the peel strength of the carrier at a lower level than that of the inorganic release layer. Here, the organic component is preferably one or more selected from nitrogen-containing organic compounds, sulfur-containing organic compounds, and carboxylic acids. Specifically, as the nitrogen-containing organic compound, 1,2,3-benzotriazole, carboxybenzotriazole (hereinafter referred to as “CBTA”), which is a triazole compound having a substituent, N ′, N′-bis. It is preferable to use (benzotriazolylmethyl) urea, 1H-1,2,4-triazole, 3-amino-1H-1,2,4-triazole, imidazole, or the like. And as a sulfur containing organic compound, it is preferable to use mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazole thiol, etc. As the carboxylic acid, it is particularly preferable to use a monocarboxylic acid, and it is particularly preferable to use oleic acid, linoleic acid, linolenic acid, or the like. And it is preferable that the thickness of this organic peeling layer is 1 nm-100 nm.

  Moreover, it is preferable that the peeling layer in this invention is equipped with "the metal dispersion layer containing an organic component" on the surface of either the inorganic peeling layer or the organic peeling layer mentioned above. The metal dispersion layer is a layer containing an organic component and a metal component, and is provided on the surface of either the inorganic release layer or the organic release layer after providing the inorganic release layer or the organic release layer on the surface of the carrier. Is. By adopting this metal dispersion layer, the “organic component” and the “metal component” can be present in an appropriate and uniform manner on the surface of the copper foil after the carrier peeling, and the metal on the surface of the inorganic peeling layer or the organic peeling layer. As compared with the case where no dispersion layer is provided, good antioxidant properties can be obtained. At this time, the “organic component” is preferably the organic component used in the organic release layer. The “metal component” preferably contains nickel and / or cobalt as a main component. This is because it has excellent heat stability when processed into a copper-clad laminate and does not change the carrier peeling characteristics. The thickness of the metal dispersion layer is preferably 5 nm to 100 nm. When the thickness of the metal dispersion layer is 5 nm or more, the antioxidant property on the surface of the copper foil after carrier peeling is excellent. Moreover, when the thickness is 100 nm or less, the copper foil formed on the surface of the metal dispersion layer can be formed uniformly.

Copper foil: The copper foil provided on the surface of the aforementioned release layer of the copper foil with carrier according to the present invention is not particularly limited in the formation method, but it is preferable to employ an electrolytic method. This copper foil is laminated with an insulating resin layer to form a copper-clad laminate, and is used for circuit formation. This copper foil is not particularly limited in thickness. However, a thickness of 12 μm or less is desirable. This is because when it is thicker than 12 μm, the significance of the copper foil with carrier is lost. Moreover, the following various surface treatments can also be performed on the outer surface of the copper foil. This surface treatment is performed by appropriately combining rust prevention treatment, roughening treatment, silane coupling agent treatment, etc. according to the application. For example, a roughening process may be added to obtain an anchor effect. This is because high adhesion strength, heat resistance, and the like are improved as compared with the case where the surface of the copper foil is not roughened.

<Method for producing copper foil with carrier>
The manufacturing method of the copper foil with a carrier which concerns on this invention is a manufacturing method of the copper foil with a carrier mentioned above, Comprising: Each process of the process A, the process B, and the process C which are described below is provided. Hereinafter, each step will be described.

Step A: Step A is a step of forming an inorganic release layer or an organic release layer as a release layer on the surface of the carrier. In the step A, it is preferable to use a solution in which an organic component or an inorganic component used for forming an inorganic release layer or an organic release layer is dissolved, a dipping method in which a carrier is immersed in the solution, and a shower on the surface on which the release layer is formed. A ring method, a spray method, a dropping method, an electrodeposition method, or the like is used. However, the method for forming the release layer in the present invention is not limited to the methods listed here.

  In the case of forming the inorganic release layer, as described above, as an inorganic component, metals such as chromium, nickel, molybdenum, cobalt, iron, titanium, tungsten, phosphorus, zinc, tantalum, vanadium, or these are listed. Metal alloys, oxides of these enumerated metals, oxides of these enumerated metals, or the like can be used. In the case of forming the organic peeling layer, as described above, the organic component is a mixture of one or more selected from nitrogen-containing organic compounds, sulfur-containing organic compounds, and carboxylic acids. It can be used suitably. The concentration of the inorganic component or organic component in the solution after dissolving the inorganic component or organic component, the temperature of the solution, the treatment time, and the like can be appropriately set.

Step B: Step B is a step of forming a metal dispersion layer containing an organic component as a part of the release layer on the surface of the inorganic release layer or the organic release layer obtained in Step A. In the step B, a carrier on which an inorganic release layer or an organic release layer is formed is immersed in a metal component-containing solution in which an organic component coexists, and an anode electrode is formed on the surface of the carrier on which the inorganic release layer or the organic release layer is formed. By disposing and electrolyzing using a metal component-containing solution, a metal dispersion layer containing an organic component can be formed on the surface of the inorganic release layer or the organic release layer.

  As the organic component used for forming the metal dispersion layer, the same organic component as that used for forming the organic release layer described above can be used. Moreover, as above-mentioned as a metal component used for formation of the said metal dispersion layer, nickel and / or cobalt can be used conveniently. Thus, when forming the metal dispersion layer, by using a metal component-containing solution in which an organic component coexists, a part of the metal ions of the component is appropriately bonded to the organic component, and the copper foil width direction The effect of reducing the influence of the electric field can be obtained. Therefore, a highly uniform rust prevention effect can be obtained.

  In the method for producing a copper foil with a carrier according to the present invention, the content ratio of the metal component and the organic component in the metal component-containing solution is 0.5 mg / L of the organic component with respect to the metal component concentration of 10 g / L to 50 g / L. It is preferable to contain L-10 mg / L. When the concentration of the organic component is higher than 10 mg / L with respect to the metal component concentration of 10 g / L to 50 g / L, the peel strength between the inorganic release layer or the organic release layer and the metal dispersion layer may be insufficient. It is not preferable. On the other hand, when the concentration of the organic component is lower than 0.5 mg / L with respect to the metal component concentration of 10 g / L to 50 g / L, an effect of improving uniformity when electrodepositing the metal component by electrolysis is obtained. It becomes difficult.

Further, in step B in the method for manufacturing a copper foil with carrier according to the present invention, as the electrolysis conditions of the metal component-containing solution, it is preferable that the current density ^{0.01A / dm 2 ~10A / dm 2} .

Step C: Step C is a step of forming a copper foil on the surface of the metal dispersion layer obtained in Step B. In the process C, the method for forming the copper foil is not particularly limited, but it is preferable to employ an electrolytic method. When the electrolytic method is employed, it is preferable to use an electrolytic solution that can be used as a copper ion supply source, such as a copper sulfate-based solution or a copper pyrophosphate-based solution. In the step C, the carrier in which the metal dispersion layer is formed is immersed in the electrolytic solution, the anode electrode is disposed on the surface of the carrier on which the metal dispersion layer is formed, and electrolysis is performed by using the electrolyte. A copper foil can be formed on the surface of the layer.

According to the manufacturing method provided with the process A-process C mentioned above, the copper foil with a carrier which concerns on this invention mentioned above can be obtained. The copper foil with a carrier obtained by the production method has a “lightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling” and a “constant temperature of the copper foil after the carrier peeling at a temperature of 25 ° C. and a humidity of 50% to 70%. The difference from the “lightness L ^* value of the peeled surface after being left for 3 days in a humidified atmosphere” is within 1.5. Therefore, according to the manufacturing method of the copper foil with a carrier of this invention, it becomes possible to provide stably the copper foil with a carrier provided with the antioxidant characteristic which the copper foil after carrier peeling was excellent.

<Copper-clad laminate configuration>
The copper clad laminated board which concerns on this invention is obtained using the above-mentioned copper foil with a carrier, It is characterized by the above-mentioned. The concept of the copper clad laminate referred to in the present invention includes both a rigid copper clad laminate and a flexible copper clad laminate. If it is a rigid copper clad laminated board, it can be manufactured using a hot press system or a continuous laminating system. And if it is a flexible copper clad laminated board, it is possible to use the roll lamination system and the casting system which are the prior art.

The copper-clad laminate according to the present invention includes a laminated copper foil “brightness L ^* value of a peeled surface of a copper foil immediately after carrier peeling” and “a copper foil after carrier peeling at a temperature of 25 ° C. and a humidity of 50% to 50%. The difference from the “lightness L ^* value of the peeled surface after being left for 3 days in a 70% constant temperature humidified atmosphere” is within 1.5. Therefore, even if the carrier of the copper-clad laminate is peeled off and left in the atmosphere for 3 days or more, there are few variations in the laser drilling of the copper foil and the etching process during pattern formation. Therefore, in the copper clad laminate according to the present invention, since the copper foil layer on the surface thereof has good anti-oxidation characteristics, it is possible to form the hole diameter and circuit width within the required range. Further, it is possible to avoid a possibility that the circuit is remarkably thinned and disconnection occurs.

<Form of printed wiring board>
The printed wiring board which concerns on this invention is obtained using the above-mentioned copper foil with a carrier, It is characterized by the above-mentioned. There is no special limitation regarding the manufacturing method of the printed wiring board which concerns on this invention. For example, if a circuit is formed by etching the above-described rigid copper-clad laminate, a rigid printed wiring board can be obtained. Moreover, if a circuit is formed by etching a flexible copper-clad laminate, a flexible printed wiring board having good bending performance can be obtained. The copper foil with a carrier according to the present invention is suitable for forming a fine pattern circuit required for a printed wiring board because the surface of the copper foil after peeling the carrier has an excellent antioxidant property. Furthermore, the printed wiring board according to the present invention can be used for laser drilling or patterning on the copper foil layer on the surface even if the carrier is peeled off at the stage of the copper clad laminate and left in the atmosphere for 3 days or more. There is little variation in the etching process during formation. Therefore, the printed wiring board according to the present invention can form a hole diameter according to a required range or a circuit having a circuit width. Further, it is possible to avoid a possibility that the circuit is remarkably thinned and disconnection occurs.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

  As the copper foil with a carrier, implementation samples A to E were prepared in which a carrier, a release layer, and a copper foil were laminated in this order. The working samples A to E differ only in the composition of the solution forming the used release layer, and the other sample preparation conditions are the same. Hereinafter, after describing the implementation sample A, the implementation samples B to E will be described with respect to differences from the implementation sample A.

Example Sample A: Example Sample A uses an electrolytic copper foil having a width of 1350 mm and a thickness of 18 μm as a carrier and is dipped in a dilute sulfuric acid solution having a sulfuric acid concentration of 150 g / L and a liquid temperature of 30 ° C. for 30 seconds to perform pickling treatment. The oil component and the surface oxide film adhering to the surface were removed.

  Next, the pickled carrier was immersed in a solution having a CBTA concentration of 5 g / L, a liquid temperature of 40 ° C., and a pH of 5 for 30 seconds to form an organic release layer having a thickness of 10 nm on the surface of the carrier.

Then, the carrier on which the organic release layer is formed is immersed in a solution having a nickel concentration of 20 g / L, a CBTA concentration of 0.5 mg / L, a liquid temperature of 40 ° C., and a pH of 3 produced using nickel sulfate, and a current density of 8 A / dm ^2. The nickel layer containing a 90 nm-thick organic component was formed as a metal dispersion layer on the surface of the organic release layer.

Then, it is immersed in a copper solution having a copper concentration of 65 g / L and a sulfuric acid concentration of 150 g / L and having a liquid temperature of 45 ° C., and electrolyzed under the condition of a current density of 15 A / dm ^2. An implementation sample A was formed and laminated in the order of carrier / release layer (organic release layer / metal dispersion layer) / copper foil.

Example Sample B: In Example Sample B, the CBTA concentration of the solution forming the metal dispersion layer was 2 mg / L.

Example C: In Example C, the CBTA concentration of the solution forming the metal dispersion layer was 5 mg / L.

Example Sample D: Example Sample D used a solution having a chromium concentration of 5 g / L as a solution for forming an inorganic release layer. Moreover, the solution similar to the implementation sample B was used for forming the metal dispersion layer.

Implementation sample E: Implementation sample E is a carrier having an organic release layer formed in the same manner as implementation sample A. Cobalt concentration is 20 g / L, CBTA concentration is 2 mg / L, liquid temperature is 40 ° C., and pH is 3 It was immersed in a solution and electrolyzed under conditions of a current density of 1 A / dm ² to form a cobalt layer containing an organic component having a thickness of 90 nm as a metal dispersion layer on the surface of the organic release layer.

Comparative example

  As a comparative example of the copper foil with a carrier according to the present invention, a comparative sample containing no organic component or inorganic component in the solution forming the metal dispersion layer was prepared. Specifically, as the solution for forming the metal dispersion layer, a solution having a nickel concentration of 20 g / L prepared using nickel sulfate and containing no organic component or inorganic component was used. Other than that, the comparative sample was produced on the same conditions as the implementation sample A. FIG.

Each of the above-mentioned implementation samples A to E and the copper foil with a carrier of the comparative sample were brought into contact with a prepreg (manufactured by Mitsubishi Gas Chemical Co., Inc .: GHPL-830NX-A), and a press pressure was applied using a vacuum press. Lamination was performed under the conditions of 9 MPa, a temperature of 220 ° C., and a press time of 90 minutes to produce a 50 cm square copper-clad laminate. And the carrier is peeled from the copper-clad laminate produced using the copper foil with carrier of each of the implementation samples A to E and the comparative sample, and the lightness L ^* immediately after the carrier peeling on the peeled surface of the copper foil after the carrier peeling ^. Value, difference in lightness L ^* value before and after standing, and standard deviation (σ) of lightness L ^* value after the standing period were measured to confirm the presence or absence of antioxidant properties.

Evaluation method of lightness L ^* value immediately after carrier peeling: About the obtained copper clad laminated board immediately after carrier peeling, the lightness L ^* value was measured about the predetermined location of the peeling surface of copper foil. The lightness L ^* value was measured according to JIS standard Z8722 using a spectroscopic color difference meter SE2000 manufactured by Nippon Denshoku Industries Co., Ltd., and the lightness L ^* value was obtained from the result based on JIS standard Z8729.

Evaluation method of difference in lightness L ^* value before and after standing: The obtained copper-clad laminate after peeling of the carrier is left indoors (temperature 25 ° C., humidity 50% to 70%) for 3 days, and once a day. time lightness L ^* value was measured for a predetermined portion of the release surface of the copper foil after the carrier peeling, the peeled surface after the lapse of lightness L ^* value and a predetermined time of the release surface of the copper foil after the carrier peeling described above for The difference from the lightness L ^* value was determined.

Evaluation method of standard deviation (σ) of lightness L ^* value after standing period: After leaving the obtained copper-clad laminate after peeling of the carrier indoors (temperature 25 ° C., humidity 50% to 70%) for 3 days The brightness L ^* value of the peeled surface of the copper foil after the carrier peeling was measured at 10 points at intervals of 10 cm in the width direction of the copper foil. And the dispersion | variation (standard deviation: (sigma)) of the brightness L ^* value of the width direction 3 days after the leaving period of the said copper foil was calculated | required.

[Contrast between Example and Comparative Example]
Table 1 summarizes the evaluation results of the implementation samples A to E and the comparative sample, and the conditions at the time of preparation of the implementation samples A to E and the comparison sample (solution for forming the inorganic release layer or organic release layer, solution for forming the metal dispersion layer). Show. While referring to the results shown in Table 1, the examples of the present invention and the comparative examples are compared.

(Evaluation of brightness L ^* value immediately after carrier peeling)
The lightness L ^* value of the peeled surface of the copper foil immediately after carrier peeling was 50 or less for all of the implementation samples A to E, whereas the comparative sample was 52.7.

(Evaluation of lightness L ^* value difference before and after leaving)
Maximum value of the difference between the lightness L ^* value in lightness L ^* value and day 0 in until the third day, while exemplary sample A~E are both was within 1.5, comparison sample, 5.0.

(Evaluation of standard deviation (σ) of lightness L ^* value after standing period)
The variation (standard deviation: σ) of the brightness L ^* value of the peeled surface of the copper foil after carrier peeling was 1 or less for all of the working samples A to E, whereas the comparative sample was 1.8. It was.

  Here, about each copper foil of these implementation samples AE and a comparative sample, the variation of the hole diameter in the laser drilling process accompanying oxidation and the variation of the etching process were confirmed. As a result, the comparative sample was confirmed to have a large variation in the hole diameter and the etching treatment, whereas the implementation samples A to E were not confirmed to have a large variation in the hole diameter and the etching treatment.

Therefore, the lightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling and the lightness L of the peeled surface of the copper foil after being left for 3 days in a constant temperature humidified atmosphere at 25 ° C. and 50% to 70% after carrier peeling. ^* If the difference from the value is within 1.5, it can be determined that the peeled surface of the copper foil after carrier peeling has uniform antioxidant properties within the same surface. Moreover, when the copper foil obtained by peeling the carrier of the copper foil with a carrier in a constant temperature and humid atmosphere with a humidity of 50% to 70% at 25 ° C. is left for 3 days, the copper foil If the standard deviation (σ) of the lightness L ^* value measured at intervals of 10 cm in the width direction is 1 or less, it can be determined that the copper foil has excellent antioxidant characteristics with little variation over the width direction of the copper foil. Furthermore, if the lightness L ^* value of the copper foil surface immediately after carrier peeling is 50 or less, vias with a uniform hole diameter can be formed by laser processing, and the uniformity within the same plane of the etching process during pattern formation can be improved. I can say that.

  By adopting the copper foil with carrier and the method for producing the copper foil with carrier according to the present invention, it is possible to effectively prevent oxidation of the peeled surface of the copper foil after carrier peeling. Therefore, according to the copper foil with a carrier and the method for producing a copper foil with a carrier according to the present invention, it is possible to provide a copper foil with a carrier that is unlikely to be oxidized in the copper foil after peeling the carrier. It can employ | adopt suitably for electronic components, such as a material for wiring boards.

Copper foil with carrier: The copper foil with carrier according to the present invention is a copper foil with carrier laminated in the order of a carrier, a release layer, and a copper foil, and the release layer is an inorganic release layer or an organic layer using an inorganic component. An organic release layer using components and a metal dispersion layer containing an organic component and nickel and / or cobalt as a main component between the inorganic release layer or the organic release layer and the copper foil. There, left and lightness L ^* value of the release surface of the copper foil after the carrier peel of the copper foil with carrier, under constant temperature humidified atmosphere of copper foil after the carrier peel temperature 25 ° C. and a humidity of 50% to 70% 3 days The difference between the lightness L ^* value of the peeled surface after the treatment is 1.5 or less.

Copper-clad laminates: copper-clad laminate according to the present invention is characterized by comprising the above-described copper foil with carrier.

Manufacturing method of a printed wiring board: The manufacturing method of the printed wiring board which concerns on this invention manufactures a printed wiring board using the copper foil with a carrier mentioned above.

<Copper foil with carrier>
The copper foil with a carrier according to the present invention is a copper foil with a carrier laminated in the order of a carrier, a release layer, and a copper foil, and the release layer is an organic using an inorganic release layer using an inorganic component or an organic component. It is provided with a release layer and a metal dispersion layer containing an organic component and nickel and / or cobalt as a main component between the inorganic release layer or the organic release layer and the copper foil . The brightness L ^* value of the peeled surface of the copper foil immediately after the peeling of the copper foil and the peeling after leaving the copper foil after the carrier peeling in a constant temperature humidified atmosphere at a temperature of 25 ° C. and a humidity of 50% to 70% for 3 days. The difference from the lightness L ^* value of the surface is within 1.5. The peeling surface of copper foil here is the surface on the side where the carrier of copper foil is peeled off. Hereinafter, the surface of the copper foil carrier from which the carrier has been peeled is referred to as a peeled surface. And this copper foil with a carrier is equipped with the layer structure laminated | stacked in order of "carrier", "peeling layer", and "copper foil". Therefore, in the following, “lightness L ^* value”, “carrier”, “release layer”, and “copper foil” will be described in order.

Release layer: In the present invention, the release layer is a layer that exists in a state of being sandwiched between the carrier and the copper foil, and enables the carrier to be peeled off. The copper foil with carrier according to the present invention, the release layer have use either "inorganic release layer using an inorganic component" or "organic release layer using an organic component" any inorganic release layer or organic release layer The surface is provided with a “metal dispersion layer containing an organic component”. Hereinafter, it demonstrates in order.

“Metal dispersion layer” is a layer containing an organic component and a metal component. After providing an inorganic release layer or an organic release layer on the surface of a carrier, it is provided on the surface of any one of these inorganic release layer or organic release layer. It is what By adopting this metal dispersion layer, the “organic component” and the “metal component” can be present in an appropriate and uniform manner on the surface of the copper foil after the carrier peeling, and the metal on the surface of the inorganic peeling layer or the organic peeling layer. As compared with the case where no dispersion layer is provided, good antioxidant properties can be obtained. At this time, the “organic component” is preferably the organic component used in the organic release layer. The "metal component", as main components of nickel and / or cobalt. This is because the heat-resistant stability when processing into a copper-clad laminate is excellent, and the peeling characteristics of the carrier are not changed. The thickness of the metal dispersion layer is preferably 5 nm to 100 nm. When the thickness of the metal dispersion layer is 5 nm or more, the antioxidant property on the surface of the copper foil after carrier peeling is excellent. Moreover, when the thickness is 100 nm or less, the copper foil formed on the surface of the metal dispersion layer can be formed uniformly.

<Copper-clad laminate configuration>
Copper-clad laminate according to the present invention is characterized by having a copper foil with carrier described above. The concept of the copper clad laminate referred to in the present invention includes both a rigid copper clad laminate and a flexible copper clad laminate. If it is a rigid copper clad laminated board, it can be manufactured using a hot press system or a continuous laminating system. And if it is a flexible copper clad laminated board, it is possible to use the roll lamination system and the casting system which are the prior art.

<Mode of manufacturing printed wiring board>
The printed wiring board manufacturing method according to the present invention is characterized by manufacturing a printed wiring board using the above-described copper foil with a carrier. There is no special limitation regarding the manufacturing method of the printed wiring board which concerns on this invention. For example, if a circuit is formed by etching the above-described rigid copper-clad laminate, a rigid printed wiring board can be obtained. Moreover, if a circuit is formed by etching a flexible copper-clad laminate, a flexible printed wiring board having good bending performance can be obtained. The copper foil with a carrier according to the present invention is suitable for forming a fine pattern circuit required for a printed wiring board because the surface of the copper foil after peeling the carrier has an excellent antioxidant property. Furthermore, the printed wiring board according to the present invention can be used for laser drilling or patterning on the copper foil layer on the surface even if the carrier is peeled off at the stage of the copper clad laminate and left in the atmosphere for 3 days or more. There is little variation in the etching process during formation. Therefore, the printed wiring board according to the present invention can form a hole diameter according to a required range or a circuit having a circuit width. Further, it is possible to avoid a possibility that the circuit is remarkably thinned and disconnection occurs.

Claims (10)

It is a copper foil with a carrier laminated in the order of carrier, release layer, copper foil,
The lightness L ^* value of the peeled surface of the copper foil immediately after the carrier peeling of the copper foil with carrier and the copper foil after the carrier peeling after being left for 3 days in a constant temperature humidified atmosphere at a temperature of 25 ° C. and a humidity of 50% to 70% The copper foil with a carrier is characterized in that the difference between the peeled surface lightness L ^* value is 1.5 or less. The copper foil after the carrier peeling was left for 3 days in a constant temperature humidified atmosphere at a temperature of 25 ° C. and a humidity of 50% to 70%, and then peeled off from the copper foil measured at a plurality of positions at 10 cm intervals in the width direction of the copper foil. The copper foil with a carrier according to claim 1, wherein the standard deviation σ of the brightness L ^* value of the surface is 1 or less. The copper foil with a carrier according to claim 1 or 2, wherein a brightness L ^* value of a peeled surface of the copper foil immediately after the carrier is peeled is 50 or less.   The copper foil with a carrier according to any one of claims 1 to 3, wherein the release layer is an inorganic release layer using an inorganic component or an organic release layer using an organic component.   The copper foil with a carrier according to claim 4, wherein the release layer further comprises a metal dispersion layer containing an organic component between the inorganic release layer or the organic release layer and the copper foil.   The copper foil with a carrier according to claim 4 or 5, wherein the organic component is one or more selected from a nitrogen-containing organic compound, a sulfur-containing organic compound, and a carboxylic acid.   The copper foil with a carrier according to claim 5, wherein the metal dispersion layer contains nickel and / or cobalt as a main component. It is a manufacturing method of the copper foil with a carrier in any one of Claims 1-7,
The manufacturing method of the copper foil with a carrier characterized by providing each process of A, B, and C described below.
A: A step of forming an inorganic release layer or an organic release layer as a release layer on the surface of the carrier.
B: The process of forming the metal dispersion layer containing an organic component as a peeling layer on the surface of the said inorganic peeling layer or the organic peeling layer.
C: A step of forming a copper foil on the surface of the metal dispersion layer.   A copper clad laminate obtained by using the copper foil with a carrier according to any one of claims 1 to 7.   A printed wiring board obtained by using the copper foil with a carrier according to any one of claims 1 to 7.