TW201929165A - Copper foil for heat dissipation and heat dissipation member - Google Patents

Abstract

Provided is a copper foil for heat dissipation, which has excellent heat dissipation characteristics. A copper foil for heat dissipation, which comprises a copper foil base material and a polymer film that is arranged on at least one main surface of the copper foil base material.

Description

   Copper foil for heat radiation and heat radiation parts   

The present invention relates to a copper foil for heat radiation and a heat radiation member.

In recent years, along with miniaturization and high precision of electronic equipment, problems such as failure due to heat generation of electronic components used have become problems. Traditionally, various researches have been conducted to release the heat of components in such electronic equipment. Development (Patent Literature 1 and the like).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 08-078461

The mounting substrate of an electronic device usually has an element that generates heat due to use. However, if the heat of the element cannot be released well, there is a risk of failure.

Here, an object of an embodiment of the present invention is to provide a copper foil for heat dissipation and a heat dissipation member having excellent heat dissipation characteristics.

That is, one embodiment of the copper foil for heat dissipation of the present invention is characterized by comprising: a copper foil substrate; and a polymer film on at least one of the main surfaces of the aforementioned copper foil substrate.

One embodiment of the copper foil for heat dissipation of the present invention, wherein the thickness of the polymer film is 0.1 μm to 10 μm.

In one embodiment of the copper foil for heat dissipation of the present invention, the thickness of the polymer film is 0.5 μm to 8 μm.

One embodiment of the copper foil for heat dissipation of the present invention, wherein the thickness of the polymer film is 1 μm to 5 μm.

In one embodiment of the copper foil for heat dissipation of the present invention, the polymer film is a polymer containing at least one type of hetero atom in a repeating unit.

One embodiment of the copper foil for heat dissipation of the present invention, wherein the polymer includes at least one selected from the group consisting of a carbonyl group, a carboxyl group, an ether group, an epoxy group, a hydroxyl group, and a halogen in the repeating unit. .

One embodiment of the copper foil for heat dissipation of the present invention, wherein the polymer is selected from the group consisting of polyester resin, polycarbonate resin, polyvinyl alcohol resin, cellulose resin, epoxy resin, nylon resin, and polyether. At least one of the group consisting of resin and fluororesin.

An embodiment of the copper foil for heat dissipation of the present invention, wherein the polymer is selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, Cellulose acetate, cellulose triacetate, cellophane, bisphenol A epoxy resin, polycaprolactam, polydodecylamine, polyethylene oxide, polypropylene oxide, polyvinylidene fluoride, and At least one of the groups of polytetrafluoroethylene.

In one embodiment of the copper foil for heat dissipation of the present invention, at least one of the main surfaces of the copper foil substrate has a plating treatment layer; and the plating treatment layer has the polymer film.

In one embodiment of the copper foil for heat dissipation of the present invention, the surface roughness Ra of the plating treatment surface of the plating treatment layer is 0.30 to 1.50.

One embodiment of the copper foil for heat dissipation of the present invention, wherein the surface roughness Rz of the plating treatment surface of the aforementioned plating treatment layer is 2.50 to 9.50.

In one embodiment of the copper foil for heat dissipation of the present invention, the plating treatment layer has a roughened particle layer.

In one embodiment of the copper foil for heat dissipation of the present invention, the plating treatment layer has a coating layer on the roughened particle layer.

In one embodiment of the copper foil for heat dissipation of the present invention, the coating layer contains at least one selected from the group consisting of Cu, Zn, Ni, Co, Cr, W, and Fe.

In one embodiment of the copper foil for heat dissipation of the present invention, the coating layer contains Co and Ni.

An embodiment of the copper foil for heat dissipation of the present invention, wherein the coating layer includes: a coating lower layer and a coating upper layer on the coating lower layer; the coating lower layer contains Cu, Co, and Ni; and the coating The upper layer contains Co and Ni.

One embodiment of the copper foil for heat dissipation according to the present invention, wherein the thickness of the coating layer is 0.001 to 1.0 m.

In one embodiment of the copper foil for heat dissipation of the present invention, the thickness of the coating layer is 0.002 μm to 0.5 μm.

One embodiment of the copper foil for heat dissipation of the present invention, wherein the thickness of the coating layer is 0.005 μm to 0.3 μm.

In addition, an embodiment of the heat radiation member of the present invention is characterized by including the above-mentioned copper foil for heat radiation.

According to the embodiment of the present invention, a copper foil for heat dissipation having excellent heat dissipation characteristics can be provided.

1‧‧‧ laminated body

10‧‧‧Insulation

20‧‧‧ heater

30‧‧‧ Adhesive

40‧‧‧SUS board

50‧‧‧ Thermal grease

60‧‧‧copper foil

70‧‧‧Black Body Tape

100‧‧‧ Infrared Thermal Imager

[Fig. 1] A schematic cross-sectional view showing a method for evaluating the thermal imaging display temperature in Examples 1 to 11 and Comparative Examples 1 to 3. [Fig.

Hereinafter, the present invention is not limited to each embodiment, and the constituent elements can be modified and embodied as long as they do not depart from the gist thereof. In addition, various inventions can be formed by appropriately combining plural constituent elements described in each embodiment. For example, some of the constituent elements shown in the implementation form may be deleted. Furthermore, the constituent elements of different implementation types can be appropriately combined.

In recent years, mobile devices such as smart phones and tablet PCs have been actively developed. Further integration of high-integration and high-output substrates into miniaturized devices has caused increasing concerns about heat dissipation. Here, the inventor, as a result of in-depth research and review, found that by having a polymer film on at least one of the main surfaces of the copper foil substrate, the heat dissipation characteristics of the copper foil can be improved.

Hereinafter, a copper foil for heat dissipation according to an embodiment of the present invention will be described.

A copper foil for heat dissipation according to an embodiment of the present invention includes a copper foil base material and a polymer film on at least one main surface of the copper foil base material. According to this embodiment mode, the polymer film can have excellent heat dissipation characteristics.

(Copper foil substrate)

The type of the copper foil substrate that can be used in this embodiment is not particularly limited. In addition, a typical copper foil substrate used in this embodiment may be either electrolytic copper foil or rolled copper foil. Generally speaking, electrolytic copper foil is produced by electrolyzing copper on a titanium or stainless steel drum with a copper sulfate plating bath, and rolled copper foil is produced by repeatedly performing plastic processing and heat treatment with a calender roll. The rolled copper foil is often used in applications requiring flexibility. In addition, the term "copper foil base material" in this specification includes a copper alloy foil base material when used alone. The thickness of the copper foil substrate is preferably 1 μm or more in the production, for example, without wrinkles. However, considering thin phones such as smart phones or tablet PCs. The miniaturized specifications are preferably 20 μm or less.

(Polymer film)

In this embodiment, in order to improve the heat radiation property, the polymer film is preferably a polymer having at least one type of hetero atom in the repeating unit. The reason is that the heat radiation characteristics are closely related to the chemical structure of the resin in the coating film. It can be deduced that the polymer with more broad-spectrum strong infrared absorption peaks has higher emissivity.

The polymer, which shows most broad-spectrum strong infrared absorption peaks, preferably contains at least one selected from the group consisting of a carbonyl group, a carboxyl group, an ether group, an epoxy group, a hydroxyl group, and a halogen in the repeating unit. This polymer is not particularly limited as long as it is a polymer having a chemical structure showing a large broad spectrum of strong infrared absorption peaks, and examples thereof include polyester resins, polycarbonate resins, polyvinyl alcohol resins (PVA), and fibers. Plain resin, epoxy resin, nylon resin, polyether resin, and fluorine resin.

The polyester resin is not particularly limited, and examples thereof include polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate.

The polycarbonate resin is not particularly limited, and examples thereof include those produced from 2,2-bis (4-hydroxybenzene) propane (bisphenol A).

Polyvinyl alcohol resin refers to the saponification of polyvinyl acetate.

The cellulose resin is not particularly limited, and examples thereof include cellulose acetate, cellulose triacetate, and cellophane.

The epoxy resin is not particularly limited, and examples thereof include a bisphenol A type epoxy resin and the like.

The nylon resin is not particularly limited, and examples thereof include polycaprolactam (nylon 6), polydodecylamine (nylon 12), and the like.

The polyether resin is not particularly limited, and examples thereof include polyethylene oxide and polypropylene oxide.

The fluororesin is not particularly limited, and examples thereof include polyvinylidene fluoride and polytetrafluoroethylene.

The thickness of the polymer film is preferably 0.1 μm or more, more preferably 0.5 μm or more, more preferably 1 μm or more, and even more preferably 2 μm or more in order to improve heat radiation. However, considering thin phones such as smart phones or tablet PCs. The miniaturization specification is preferably 10 μm or less, 8 μm or less is preferable, 5 μm or less is more preferable, and 3 μm or less is more preferable. The thickness of the polymer film refers to the average thickness of the polymer film.

A method of measuring the thickness of the polymer film is described below as an example of a method of a measuring device.

First, the thickness of the copper foil substrate was measured by three or more points with a meter thickness gauge, and the average value of the three or more points was calculated. Next, a copper foil for heat dissipation having a polymer film on the copper foil substrate was prepared. In addition, the thickness of the copper foil for heat dissipation was measured by three or more points with a meter thickness gauge, and the average value of the three or more points was calculated. The thickness (average thickness) of the polymer film is calculated from the average value of the thickness of the copper foil for heat dissipation and subtracting the average value of the thickness of the aforementioned copper foil base material.

In addition, the case where the copper foil for heat radiation has a roughened particle layer and a polymer film, or a roughened particle layer, a coating layer, and a polymer film on the main surface of a copper foil base material is as follows. First, the thickness of the copper foil that forms the roughened particle layer, or the roughened particle layer and the coating layer on the main surface of the copper foil substrate is measured by an instrument thickness gauge, and the average of the three or more points is calculated. value. Next, a copper foil for heat dissipation having a roughened particle layer and a polymer film on the main surface of the copper foil base material, or a roughened particle layer, a coating layer, and a polymer film was prepared. In addition, the thickness of the copper foil for heat dissipation was measured by three or more points with a meter thickness gauge, and the average value of the three or more points was calculated. The thickness (average thickness) of the polymer film is calculated from the average value of the thickness of the copper foil for heat dissipation and subtracting the average value of the aforementioned thickness of the copper foil.

In addition, in this embodiment, in order to improve the adhesion between the copper foil substrate and the polymer film, a rust preventive layer may be formed on the copper foil substrate, and a chromate treatment may be further applied on the surface. Silane coupling treatment. The rust preventive layer and the silane coupling treatment can be used by a conventional person.

(Plating treatment layer)

This embodiment is based on at least one main surface of the copper foil substrate, and further has a plating treatment layer, and it is preferable to have a polymer film on the plating treatment layer.

In this embodiment, the surface roughness Ra of the plating treatment surface of the plating treatment layer is preferably 0.30 or more, more preferably 0.40 or more, and even more preferably 0.45 or more in order to dissipate the heat generated by the heating element. However, in order to prevent the roughened particles from falling off easily due to external force, it is preferably 1.50 or less, more preferably 1.30 or less, and even more preferably 1.20 or less. The surface roughness Ra is an arithmetic average roughness described in JIS B 0601: 2013.

In addition, in the present embodiment, the surface roughness Rz of the plated surface is preferably 2.50 or more, preferably 3.00 or more, and even more preferably 3.72 or more in order to dissipate the heat generated by the heating element. However, in order to prevent the roughened particles from falling off easily due to external forces, it is preferably below 9.50, more preferably below 8.00, and even more preferably below 7.74. The surface roughness Rz represents the maximum height roughness described in JIS B 0601: 2013.

In this embodiment, the surface area ratio B / A of the surface area B of the plated surface to the projected area A of the plated surface when the plated surface of the plated layer is measured using a laser microscope is not particularly limited. For example, in order to further improve the heat radiation of the plated layer, the surface area ratio B / A is preferably 1.42 or higher, 1.60 or higher, 1.81 or higher, 2.18 or higher, or 2.35 or higher. However, even if the surface area ratio B / A is higher, the heat radiation of the plating treatment layer is better, but the roughened particles may easily fall off due to external forces. Therefore, the surface area ratio B / A is preferably less than 3.42, and less than 3.25 Good, it is further preferred below 3.10, further preferred below 2.98, and further preferred below 2.88.

(Roughened particle layer)

In this embodiment, it is preferable that the plated layer has a roughened particle layer in order to improve the heat radiation property. That is, in this embodiment, a roughened particle layer and a polymer film are sequentially formed on at least any one of the main surfaces of the copper foil substrate. In the roughened particle layer, the roughening treatment can be performed, for example, by forming roughened particles with copper or a copper alloy. The roughening treatment can also be fine.

In the case of a roughened particle layer and a polymer film on the roughened particle layer, the polymer film is coated on the surface of the roughened particles. Accordingly, by covering the surface of the roughened particles with the polymer film, the surface area of the polymer film is increased, thereby further improving the heat radiation property.

In addition, the front end portion of the roughened particles is broken, or the roughened particles are peeled off from the foundation, and the problem is generally called a dusting phenomenon. This dusting phenomenon, although the roughened particle layer subjected to the roughening plating process has excellent heat radiation properties, the roughened particles are liable to fall off due to external forces, and peeling occurs due to "friction" when making or using copper foil. Here, in this embodiment, in order to suppress dusting, the surface of the roughened particles is covered with a polymer film. Accordingly, the front end portion of the roughened particles is thickened by the polymer film, and the basis of the roughened particles is thickened by the coating layer and the polymer film. In this way, by forming a polymer film on the roughened particle layer, the roughened particles can be prevented from falling off easily due to an external force, and dusting can be suppressed.

(Cover layer)

In this embodiment, the plating treatment layer preferably has a roughened particle layer and a coating layer on the roughened particle layer. That is, in this embodiment, at least any major surface of the copper foil substrate is sequentially formed: a roughened particle layer, a coating layer, and a polymer film. This coating layer covers the surface of the branches of the roughened particles. Further, a polymer film is formed on the coating layer. Therefore, in this embodiment, since the coating layer has a polymer film, the synergistic effect between the coating layer and the polymer film further improves the heat radiation property and also improves the dusting characteristics.

The roughened particle layer may be further formed from copper, Zn, Ni, Co, Cr, and the like from the viewpoints of heat radiation, dusting, and adhesion after forming roughened particles with copper or a copper alloy. A smooth plating treatment of a coating layer of at least one of W and Fe groups. For example, the roughened particle layer preferably has a coating lower layer and a coating upper layer on the coating lower layer. The coating lower layer preferably contains Cu, Co, and Ni, and the coating upper layer preferably contains Co and Ni. These metals are preferably contained in all or a part (for example, the upper part) of the coating layer.

The thickness of the coating layer is preferably 0.001 μm or more, more preferably 0.002 μm or more, more preferably 0.005 μm or more, and still more preferably 0.01 μm or more in order to improve heat radiation. However, considering thin phones such as smart phones or tablet PCs. The miniaturization specification is preferably 1.0 μm or less, more preferably 0.5 μm or less, even more preferably 0.3 μm or less, and still more preferably 0.1 μm or less. The thickness of the coating layer refers to the average thickness of the coating layer.

A method for measuring the thickness of the coating layer is described below as an example of a method for measuring weight.

First, a copper foil for heat dissipation in which a roughened particle layer and a coating layer are formed is prepared. A 2 cm × 2 cm sample was taken from the copper foil for heat dissipation, and the sample was dissolved in a 20% by volume aqueous nitric acid solution to obtain a solution. Next, this solution is quantitatively analyzed by atomic absorption spectrometry using an atomic absorption spectrophotometer to determine the concentration of each metal contained in the coating layer in the aforementioned sample, and the concentration of each metal in the coating layer in the aforementioned sample is measured using this concentration of each metal The weight is quantified. The volume of the coating layer was calculated from the weight of each metal obtained and the density of the metal. The thickness of the coating layer (average thickness) was calculated by dividing the volume of the obtained coating layer by the product of the area of the sample (4 cm ² ) and the measured surface area ratio.

In addition, in this embodiment, in order to improve the adhesion between the plating treatment layer and the polymer film, a rust prevention layer may be formed on the plating treatment layer, and the surface may be further subjected to chromate treatment and silane coupling. Processing and other processing. The rust preventive layer and the silane coupling treatment can be used by a conventional person.

Next, an example of the formation conditions (plating bath composition, plating conditions, and film conditions) of each of the roughened particle layer, the coating layer, the rust-proof layer, and the polymer film when forming the above-mentioned plating treatment layer is shown below.

(A) Coarse particle layer

The roughened particle layer is preferably formed on the main surface on either side of the copper foil base material under conditions of (A-1) roughened particle layer formation 1. In addition, in addition to the formation 1 of the roughened particle layer (A-1), it is preferable to form a roughened particle layer in which roughened particles are further grown under the conditions of formation 2 of the roughened particle layer (A-2).

(A-1) Formation of roughened particle layer 1 (Cu plating)

The process of forming the roughened particle layer 1 is a process equivalent to roughening plating (rough plating). The roughening plating is performed by setting the current density to a limit current density or higher.

Liquid composition: copper 10 ~ 20g / L; sulfuric acid 50 ~ 100g / L

Liquid temperature: 25 ~ 50 ℃

Current density: 20 ~ 58A / dm ²

Time: 0.5 ~ 5 seconds

(A-2) Formation of roughened particle layer 2 (Cu plating)

The process of forming the roughened particle layer 2 is a process equivalent to roughening plating (rough plating). The roughening plating is performed by setting the current density to a limit current density.

Liquid composition: copper 15 ~ 50g / L; sulfuric acid 60 ~ 100g / L

Liquid temperature: 25 ~ 50 ℃

Current density: 20 ~ 58A / dm ²

Time: 1 ~ 10 seconds

Further, the lower the current density and / or the larger the Coulomb amount, the larger the aforementioned effect of reducing the surface roughness Ra may be.

In addition, the roughened particle layer may be formed by performing one or more treatments.

(B) Formation of coating layer

The coating layer is formed on the roughened particle layer under the conditions of (B-1) coating the lower layer, and then the coating upper layer is preferably formed under the conditions of (B-2) coating the upper layer. Either the formation of the coating lower layer or the coating upper layer is equivalent to a smooth plating treatment. The smooth plating is a plating performed by setting the current density to a limit current density. The coating lower layer can be formed under the following conditions. In addition, the coating underlayer may not be formed.

(B-1) Conditions for forming the lower layer

An example of the conditions for forming the coating lower layer is as follows.

Liquid composition: Cu10 ~ 20g / L; at least one element selected from the group consisting of Zn, Ni, Co, Cr, W, and Fe is 0.001 ~ 15g / L

pH: 2 ~ 3

Liquid temperature: 30 ~ 50 ℃

Current density: 10 ~ 50A / dm ²

Time: 0.1 ~ 2 seconds

(B-2) Conditions for forming the upper layer

An example of the conditions for forming the coating upper layer is as follows.

Liquid composition: Cu10 ~ 20g / L; at least one element selected from the group consisting of Zn, Ni, Co, Cr, W, and Fe is 0.001 ~ 15g / L

pH: 2 ~ 3

Liquid temperature: 30 ~ 50 ℃

Current density: 0.5 ~ 20A / dm ²

Time: 0.1 ~ 300 seconds

The coated lower layer and the coated upper layer may be formed by one or two or more treatments.

(C) Anti-rust layer

In addition, a rust preventive layer may be formed on the copper foil base material, the roughened particle layer, or the coating layer, particularly a rust preventive layer of a chromate layer. The preferred rust prevention treatment in this embodiment is a coating treatment of chromium oxide alone or a coating treatment of a mixture of chromium oxide and zinc / zinc oxide. The coating of chromium oxide and zinc / zinc oxide mixture is treated by using a plating bath containing zinc salt or zinc oxide and chromate to coat the zinc-chromium-based mixture made of zinc or zinc oxide and chromium oxide. Treatment of rust layer.

Plating baths, typically, use at least one of dichromates of K ₂ Cr ₂ O ₇ , Na ₂ Cr ₂ O ₇ or CrO 3, etc .; and water-soluble zinc salts, such as ZnO, ZnSO ₄ . 7H ₂ O and the like; and a mixed aqueous solution of an alkali metal hydroxide. Typical plating bath compositions and electrolytic conditions are as follows. In the following description, the conditions for electrolytic chromate treatment are shown, but they may be immersion chromate treatment.

Plating conditions to form a rust preventive layer

Liquid composition: potassium dichromate 1 ~ 10g / L; zinc 0 ~ 5g / L

pH: 3 ~ 4

Liquid temperature: 50 ~ 60 ℃

Current density: 0 ~ 2A / dm ² (for electrolytic chromate treatment)

Time: 1 ~ 10 seconds

(D) Formation of polymer film

The polymer film is formed on the main surface on either side of the copper foil substrate. Further, it is preferable to form a polymer film on the plating treatment layer, or to form a polymer film on the anti-rust layer.

The coating method is spraying with a spray of a coating solution containing a polymer; any one of coating, dipping, and fluid bed of a coating machine is acceptable. The thickness of the polymer film is 0.1 to 10 μm by adjusting the solid content concentration or the coating amount. After that, if necessary, an annealing treatment may be performed for the purpose of improving the ductility of the copper foil.

The heat dissipating member provided with the copper foil for heat dissipating in this embodiment mode can be used, for example, to dissipate heat generating components built in mobile devices such as smart phones or tablet PCs.

[Example]

Hereinafter, it demonstrates based on an Example and a comparative example. In addition, this embodiment represents only one example, and is not limited to this example. That is, it includes other aspects or modifications included in the present invention.

<Example 1>

A polymer film was formed on the main surface on either side of a rolled copper foil (JX Metal Co., Ltd., TPC foil) having a thickness of 12 μm within the conditions shown below. The coating conditions are as follows.

(A) Formation of polymer film (PVA)

Solvent: PVA6 mass% aqueous solution

Coating method: metal applicator

Film thickness: 1.5 μm

First, about the said rolled copper foil, the surface roughness Ra and Rz and surface area ratio were evaluated. In addition, regarding the obtained copper foil for heat dissipation, the thickness of the polymer film, the thermal imaging indication temperature, and dusting were evaluated. The results are shown in Table 1. In addition, the evaluation methods of the surface roughness Ra and Rz, the surface area ratio, the thickness of the polymer film, the temperature indicated by thermal imaging, and dusting will be individually described.

(Surface roughness Ra, Rz)

The surface roughness Ra (arithmetic average roughness) of the surface of the roughened particle layer of each of the examples and comparative examples was measured using a non-contact type roughness measuring machine (laser microscope, LEXT OLS 4000 manufactured by Olympus) and Surface roughness Rz (maximum height roughness). The laser wavelength of the same measuring machine is 405nm, and the built-in lens has a magnification of 20 times. Ra and Rz were measured at arbitrary five places, and the average value of the five places of Ra and Rz was taken as the value of Ra and Rz. In addition, Ra and Rz were also measured on the surface of the copper foil base material before the roughening treatment used in each of the examples and comparative examples on the side to be roughened. The measurement of Ra and Rz was performed in the TD direction (wide direction, that is, a direction perpendicular to the rolling direction of the copper foil substrate). The setting of the main items in the measurement conditions and analysis conditions is as follows.

<Measurement conditions>

Object lens: MPLAPONLEXT 100 (magnification: 100 times; number of openings: 0.95)

Scanning mode: XYZ high precision (high resolution: 10nm, number of pixels of captured data: 1024 × 1024)

Measuring range: 130 μm horizontal × 130 μm vertical

Measuring ambient temperature: 23 ~ 25 ℃

<Analysis conditions>

Analysis area setting: None (measurement range is full-field analysis)

Demarcation: None (None of λc, λ s, λ f)

Noise reduction and tilt correction: None

(Surface area ratio)

The surface area of the plated surface was measured using a non-contact roughness measuring machine (laser microscope, LEXT OLS 4000 manufactured by Olympus). As the surface area ratio B / A, the surface area B of the plated surface with respect to the projected area A of the plated surface was used. In addition, for those having a polymer film on the plated layer, the surface area of the plated layer was measured before coating the polymer film. The setting of the main items in the measurement conditions and analysis conditions is as follows.

<Measurement conditions>

The conditions are the same as those for measuring the surface roughness Ra and Rz described above.

In addition, since the measurement range is 130 μm in width × 130 μm in length, the projected area A of the plated surface is 16923 μm ² .

Measuring ambient temperature: 23 ~ 25 ℃

<Analysis conditions>

The conditions are the same as those for the analysis of surface roughness Ra and Rz.

However, the threshold setting is a histogram; the threshold value is 0%; the threshold value is 100%.

(Thickness of polymer film)

The thickness of the copper foil for heat dissipation obtained in Example 1 was measured with an instrument thickness gauge (Ono Gauge Co., Ltd., digital counter DG-1270), and the thickness of the rolled copper foil (12 μm) was subtracted from the average value of 3 points. To calculate the thickness of the polymer film.

(Thermal imaging indicates temperature)

The measurement was performed using an infrared thermal imager (Chino Co., Ltd. CPA-0150J) under the following measurement conditions. As shown in FIG. 1, it is made in the following order: heat insulation material 10, heater 20, adhesive (East Asia Synthesis Co., Ltd., ARON ALPHA (registered trademark)) 30, SUS board 40, heat dissipation grease 50, The laminated body 1 made of the copper foil 60 for heat radiation is arrange | positioned in the envelope (not shown) formed by the heat insulation member. Further, a black body tape 70 having an emissivity of 0.9 was arranged on the copper foil 60 for heat dissipation of the laminated body so as to cover a half of the area of the copper foil 60 for heat dissipation. A DC current (current: 0.3 A; voltage 4.0 V) was applied to heat the heater 20 to the area covered by the black body tape 70 of the laminated body 1 on the infrared thermal imager 100, and the indicated temperature showed a temperature of 88.0 ° C. Using the infrared thermal imager 100, using the area covered by the black body tape 70 as a reference (88.0 ° C), the indicated temperature of the portion of the copper foil 60 for heat dissipation of the laminated body 1 was measured. Generally, the infrared thermal imager 100 detects the infrared energy emitted from the surface of the sample and uses it as the indicated temperature. When measuring the outermost surface of a sample with a low emissivity, the infrared energy emitted from the aforementioned sample is extremely small, and the actual sample temperature will differ from the indicated temperature of the thermal imaging. Here, as described above, the expression temperature of the thermal imaging of the black body tape with known emissivity is used as a reference, and the expression temperature of the thermal imaging of the copper foil for heat radiation obtained in Example 1 is compared to evaluate the thermal radiation of the copper foil for heat radiation. In Table 1, the thermal imaging indicates that the closer the temperature is to 88.0 ° C, the higher the emissivity. That is, it shows that the capability of emitting infrared rays is excellent, and the heat radiation characteristics are good.

(Dusting Assessment)

Dust evaluation was performed by attaching a transparent invisible tape (MonotaRO Co., Ltd., model number 125076) on the treated surface of the copper foil for heat dissipation obtained in Example 1, and performed it by the tape transfer method.

<Evaluation Criteria>

：: There is no case where the roughened particles are transferred.

(Circle): There exists a case where a slightly roughened particle is transferred.

×: Rough particles were transferred on the entire surface (even on the entire surface, even if slight).

<Example 2>

On the main surface of either side of a rolled copper foil (JX Metal Co., Ltd., TPC foil) with a thickness of 12 μm, except for (A) the formation of a polymer film, the solvent used was prepared as a PVA 8 mass% aqueous solution, and the polymer film Except that the thickness was changed to 2.5 μm, everything else was the same as in Example 1 to form a polymer film.

With respect to the obtained copper foil for heat dissipation, the thickness of the polymer film, the thermal imaging display temperature, and dusting were evaluated. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat dissipation in Example 1.

<Example 3>

On the main surface of either side of a rolled copper foil (JX Metal Co., Ltd., TPC foil) with a thickness of 12 μm, except for (A) the formation of a polymer film, the solvent used was prepared as a PVA 8 mass% aqueous solution, and the polymer film Except that the thickness was changed to 3.5 μm, everything else was the same as in Example 1 to form a polymer film.

With respect to the obtained copper foil for heat dissipation, the thickness of the polymer film, the thermal imaging display temperature, and dusting were evaluated. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat dissipation in Example 1.

<Example 4>

On the main surface of either side of a 12-m-thick rolled copper foil (JX Metal Co., Ltd., TPC foil), except for (A) the formation of a polymer film, the solvent used was prepared as a PVA 10% by mass aqueous solution, and the polymer film Except that the thickness was changed to 5.0 μm, the polymer film was formed in the same manner as in Example 1.

With respect to the obtained copper foil for heat dissipation, the thickness of the polymer film, the thermal imaging display temperature, and dusting were evaluated. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat dissipation in Example 1.

<Example 5>

A 12 μm-thick rolled copper foil (JX Metal Co., Ltd., TPC foil) has a roughened particle layer (Cu) and a coating layer (Cu-Ni) in order within the conditions shown below on the main surface. -Co; Ni-Co), and polymer film (PVA). The composition of the plating bath used, the plating conditions, and the formation conditions of the polymer film are as follows. In addition, the thicknesses of the copper foil (roughened particle layer and coating layer) obtained before the polymer film formation and the copper foil for heat dissipation obtained in Example 5 were measured at three points with a meter thickness gauge, and the 3 The average of points. Next, the average value of the thickness of the copper foil for heat dissipation is subtracted from the average value of the thickness of the copper foil to calculate the thickness (average thickness) of the polymer film.

[Plating bath composition and plating conditions]

(A) Formation of roughened particle layer 1 (Cu plating)

Liquid composition: copper 11g / L; sulfuric acid 50g / L

Current density: 40A / dm ²

Liquid temperature: normal temperature

Time: 1 second

Number of times: 2 times

(B) Formation of roughened particle layer 2 (Cu plating)

Liquid composition: copper 20g / L; sulfuric acid 100g / L

Current density: 19A / dm ²

Liquid temperature: 50 ℃

Time: 4.5 seconds

Number of times: 1

(C) Formation of coated lower layer (Cu-Ni-Co plating)

Liquid composition: copper 15.5g / L; nickel 9.5g / L; cobalt 7.5g / L

Current density: 15A / dm ²

pH: 2.5

Liquid temperature: 36 ℃

Time: 0.79 seconds

Number of times: 2 times

(D) Formation of coating upper layer (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 11.9A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 1 second

Number of times: 2 times

(E) Formation of polymer film (PVA)

Solvent: PVA6 mass% aqueous solution

Coating method: metal applicator

Film thickness: 1.0 μm

First, before forming a polymer film, the surface area ratio of the coated surface of the coating layer was evaluated. With respect to the obtained copper foil for heat dissipation, the thickness of the polymer film, the thermal imaging display temperature, and dusting were evaluated. The results are shown in Table 1.

<Example 6>

On the main surface of either side of a rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) with a thickness of 12 μm, except for (E) the formation of a polymer film, the solvent used was prepared as a PVA 10% by mass aqueous solution, and the polymer Except that the thickness of the film was changed to 5.0 μm, everything else was the same as in Example 5, and a roughened particle layer (Cu), a coating layer (Cu-Ni-Co; Ni-Co), and a polymer film (PVA) were sequentially formed.

First, with respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging temperature and the dusting were performed. The results are shown in Table 1. The surface area ratio of the plated surface is the value of the copper foil for heat dissipation in Example 5.

<Example 7>

A 12 μm-thick rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) on either side of the main surface, in order to form a roughened particle layer (Cu) and a coating layer (Cu) within the conditions shown below -Ni-Co; Ni-Co), rust preventive layer, and polymer film (PVA). The composition of the plating bath used, the plating conditions, and the conditions for forming the polymer film are as follows. In addition, the thickness of the copper foil (roughened particle layer, coating layer, and rust preventive layer) obtained before the formation of the polymer film and the copper foil for heat dissipation obtained in Example 7 were measured at three points with a thickness gauge. And calculate the average value of 3 points. Next, the average value of the thickness of the copper foil for heat dissipation is subtracted from the average value of the thickness of the copper foil to calculate the thickness (average thickness) of the polymer film.

[Plating bath composition and plating conditions]

(A) Formation of roughened particle layer 1 (Cu plating)

Liquid composition: copper 11g / L; sulfuric acid 50g / L

Current density: 45A / dm ²

Liquid temperature: normal temperature

Time: 0.68 seconds

Number of times: 2 times

(B) Formation of roughened particle layer 2 (Cu plating)

Liquid composition: copper 20g / L; sulfuric acid 100g / L

Current density: 4.11A / dm ²

Liquid temperature: 50 ℃

Time: 1.44 seconds

Number of times: 2 times

(C) Formation of coated lower layer (Cu-Ni-Co plating)

Liquid composition: copper 15.5g / L; nickel 9.5g / L; cobalt 7.5g / L

Current density: 30.3A / dm ²

pH: 2.5

Liquid temperature: 36 ℃

Time: 0.5 seconds

Number of times: 2 times

(D) Formation of coating 1 (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 13.7A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 0.34 seconds

Number of times: 1

(E) Formation of coating 2 (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 14.9A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 0.34 seconds

Number of times: 1

(F) Formation of anti-rust layer

Liquid composition: potassium dichromate 1 ~ 10g / L; zinc 0 ~ 5g / L

pH: 3 ~ 4

Liquid temperature: 50 ~ 60 ℃

Current density: 0 ~ 2A / dm ² (for electrolytic chromate treatment)

Coulomb amount: 0 ~ 2As / dm ² (for electrolytic chromate treatment)

(G) Polymer film formation (PVA)

Solvent: PVA4 mass% aqueous solution

Coating method: metal applicator

Film thickness: 1.0 μm

First, before forming the rust preventive layer, the surface roughness Ra and Rz and the surface area ratio of the plating-treated surface of the coating layer were evaluated. In addition, with respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging display temperature, and dusting were performed. The results are shown in Table 1.

<Example 8>

On the main surface of either side of a 12-m-thick rolled copper foil (JX Metal Co., Ltd., HA-V2 foil), except for the (G) polymer film formation, the solvent used was prepared as a PVA 6 mass% aqueous solution and polymerized. Except that the thickness of the film was changed to 1.5 μm, everything else was the same as in Example 7, and a roughened particle layer (Cu), a coating layer (Cu-Ni-Co; Ni-Co), an anti-rust layer, and a polymer were sequentially formed. Membrane (PVA).

With respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging display temperature, and dusting were performed. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat radiation of Example 7.

<Example 9>

On the main surface of either side of the rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) with a thickness of 12 μm, the solvent used except for the formation of the (G) polymer film was prepared as a PVA 8 mass% aqueous solution and polymerized. Except that the thickness of the material film was changed to 2.0 μm, everything else was the same as in Example 7, and a roughened particle layer (Cu), a coating layer (Cu-Ni-Co; Ni-Co), a rust preventive layer, and a polymer were sequentially formed. Membrane (PVA).

With respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging display temperature, and dusting were performed. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat radiation of Example 7.

<Example 10>

On the main surface of either side of the rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) with a thickness of 12 μm, the solvent used except for the formation of the (G) polymer film was prepared as a PVA 8 mass% aqueous solution and polymerized. Except that the thickness of the film was changed to 2.5 μm, the rest were the same as in Example 7, and a roughened particle layer (Cu), a coating layer (Cu-Ni-Co; Ni-Co), a rust preventive layer, and a polymer were sequentially formed. Membrane (PVA).

With respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging display temperature, and dusting were performed. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat radiation of Example 7.

<Example 11>

On the main surface of either side of the rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) with a thickness of 12 μm, except for the (G) polymer film formation, the solvent used was prepared as a 10% by mass aqueous solution of PVA and polymerized Except that the thickness of the material film was changed to 3.0 μm, everything else was the same as in Example 7, and a roughened particle layer (Cu), a coating layer (Cu-Ni-Co; Ni-Co), a rust preventive layer, and a polymer were sequentially formed. Membrane (PVA).

With respect to the obtained copper foil for heat dissipation, the evaluation of the thickness of the polymer film, the thermal imaging display temperature, and dusting were performed. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat radiation of Example 7.

<Comparative example 1>

With respect to the rolled copper foil (JX Metal Co., Ltd., TPC foil) used in Example 1, the surface roughness Ra and Rz, the surface area ratio, the temperature indicated by thermal imaging, and the dusting were evaluated. The results are shown in Table 1.

<Comparative example 2>

A 12 μm-thick rolled copper foil (JX Metal Co., Ltd., TPC foil) has a roughened particle layer (Cu) and a coating layer (Cu-Ni) sequentially formed on the main surface on either side within the conditions shown below -Co; Ni-Co). The composition and plating conditions of the plating bath used are as follows.

[Plating bath composition and plating conditions]

(A) Formation of roughened particle layer 1 (Cu plating)

Liquid composition: copper 11g / L; sulfuric acid 50g / L

Current density: 40A / dm ²

Liquid temperature: normal temperature

Time: 1 second

Number of times: 2 times

(B) Formation of roughened particle layer 2 (Cu plating)

Liquid composition: copper 20g / L; sulfuric acid 100g / L

Current density: 19A / dm ²

Liquid temperature: 50 ℃

Time: 4.5 seconds

Number of times: 1

(C) Formation of coated lower layer (Cu-Ni-Co plating)

Liquid composition: copper 15.5g / L; nickel 9.5g / L; cobalt 7.5g / L

Current density: 15A / dm ²

pH: 2.5

Liquid temperature: 36 ℃

Time: 0.79 seconds

Number of times: 2 times

(D) Formation of coating upper layer (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 11.9A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 1 second

Number of times: 2 times

With respect to the obtained copper foil for heat dissipation, the surface area ratio, the temperature indicated by thermal imaging, and dusting were evaluated. The results are shown in Table 1.

<Comparative example 3>

A 12 μm-thick rolled copper foil (JX Metal Co., Ltd., HA-V2 foil) on either side of the main surface, in order to form a roughened particle layer (Cu) and a coating layer (Cu) within the conditions shown below -Ni-Co; Ni-Co), and anti-rust layer. The composition and plating conditions of the plating bath used are as follows.

[Plating bath composition and plating conditions]

(A) Formation of roughened particle layer 1 (Cu plating)

Liquid composition: copper 11g / L; sulfuric acid 50g / L

Current density: 45A / dm ²

Liquid temperature: normal temperature

Time: 0.68 seconds

Number of times: 2 times

(B) Formation of roughened particle layer 2 (Cu plating)

Liquid composition: copper 20g / L; sulfuric acid 100g / L

Current density: 4.11A / dm ²

Liquid temperature: 50 ℃

Time: 1.44 seconds

Number of times: 2 times

(C) Formation of coated lower layer (Cu-Ni-Co plating)

Liquid composition: copper 15.5g / L; nickel 9.5g / L; cobalt 7.5g / L

Current density: 30.3A / dm ²

pH: 2.5

Liquid temperature: 36 ℃

Time: 0.5 seconds

Number of times: 2 times

(D) Formation of coating 1 (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 13.7A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 0.34 seconds

Number of times: 1

(E) Formation of coating 2 (Ni-Co plating)

Liquid composition: nickel 13g / L; cobalt 3g / L

Current density: 14.9A / dm ²

pH: 2.5

Liquid temperature: 40 ℃

Time: 0.34 seconds

Number of times: 1

(F) Formation of anti-rust layer

Liquid composition: potassium dichromate 1 ~ 10g / L; zinc 0 ~ 5g / L

pH: 3 ~ 4

Liquid temperature: 50 ~ 60 ℃

Current density: 0 ~ 2A / dm ² (for electrolytic chromate treatment)

Coulomb amount: 0 ~ 2As / dm ² (for electrolytic chromate treatment)

About the obtained copper foil for heat radiation, the evaluation of temperature and dusting by thermal imaging was performed. The results are shown in Table 1. The surface roughness Ra and Rz and the surface area ratio of the plated surface are the values of the copper foil for heat radiation of Example 7.

In Examples 1 to 11, it was confirmed that since the polymer film was provided, the heat generated by the heating element was well dissipated. In addition, in Examples 2 to 4, 6, and 9 to 11, it was confirmed that the thickness of the polymer film was 2.0 μm or more, so that the heat generated by the heating element could be better dissipated. Furthermore, in Examples 5 to 11, it was confirmed that the polymer film was formed on the coating layer made of Ni-Co, so that the heat generated by the heating element could be better dissipated, and the evaluation of dusting was also good.

[Industrial availability]

A heat radiation member using the copper foil for heat radiation according to an embodiment of the present invention has excellent heat radiation characteristics. Accordingly, the present invention provides a useful technology that, while advancing the development of electronic equipment, responds to the requirements of miniaturization or high performance, and does not cause faults and the like due to the heat generation of the electronic components used.

Claims (20)

    A copper foil for heat dissipation comprises: a copper foil substrate; and a polymer film on at least any one of the main surfaces of the copper foil substrate.         The copper foil for heat dissipation as described in item 1 of the scope of patent application, wherein the thickness of the polymer film is 0.1 μm to 10 μm.         The copper foil for heat dissipation as described in item 1 of the scope of patent application, wherein the thickness of the polymer film is 0.5 μm to 8 μm.         The copper foil for heat dissipation as described in item 1 of the scope of patent application, wherein the thickness of the polymer film is 1 μm to 5 μm.         The copper foil for heat dissipation as described in any one of claims 1 to 4, wherein the polymer film is a polymer including at least one type of hetero atom in a repeating unit.         The copper foil for heat dissipation as described in claim 5 of the patent application scope, wherein the polymer contains at least one group selected from the group consisting of a carbonyl group, a carboxyl group, an ether group, an epoxy group, a hydroxyl group, and a halogen in the repeating unit 1 species.         The copper foil for heat dissipation according to item 5 of the scope of patent application, wherein the polymer is selected from the group consisting of polyester resin, polycarbonate resin, polyvinyl alcohol resin, cellulose resin, epoxy resin, nylon resin, At least one of a group consisting of a polyether resin and a fluororesin.         The copper foil for heat dissipation as described in item 5 of the scope of patent application, wherein the polymer is selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate. Ester, cellulose acetate, cellulose triacetate, cellophane, bisphenol A epoxy resin, polycaprolactam, polydodecylamine, polyethylene oxide, polypropylene oxide, polyvinylidene fluoride And at least one of the groups of polytetrafluoroethylene.         The copper foil for heat dissipation as described in any one of claims 1 to 4, wherein at least one of the main surfaces of the copper foil substrate further has a plating treatment layer; and on the foregoing plating treatment layer, It has the aforementioned polymer film.         The copper foil for heat dissipation as described in item 9 of the scope of the patent application, wherein the surface roughness Ra of the plating treatment surface of the plating treatment layer is 0.30 to 1.50.         The copper foil for heat dissipation as described in item 9 of the scope of the patent application, wherein the surface roughness Rz of the plating treatment surface of the aforementioned plating treatment layer is 2.50 to 9.50.         The copper foil for heat radiation as described in claim 9 of the patent application range, wherein the plating treatment layer has a roughened particle layer.         The copper foil for heat dissipation as described in claim 12 of the patent application scope, wherein the plating treatment layer has a coating layer on the roughened particle layer.         The copper foil for heat dissipation as described in claim 13 of the patent application scope, wherein the coating layer contains at least one selected from the group consisting of Cu, Zn, Ni, Co, Cr, W, and Fe.         The copper foil for heat dissipation as described in claim 13 of the patent application range, wherein the coating layer contains Co and Ni.         The copper foil for heat dissipation according to item 13 of the scope of the patent application, wherein the coating layer includes: a coating lower layer and a coating upper layer on the coating lower layer; and the coating lower layer contains Cu, Co, and Ni; The coating upper layer contains Co and Ni.         The copper foil for heat dissipation according to item 13 of the scope of patent application, wherein the thickness of the coating layer is 0.001 μm to 1.0 μm.         The copper foil for heat dissipation as described in item 13 of the scope of the patent application, wherein the thickness of the coating layer is 0.002 μm to 0.5 μm.         The copper foil for heat dissipation as described in item 13 of the scope of patent application, wherein the thickness of the coating layer is 0.005 μm to 0.3 μm.         A heat-dissipating member characterized by including the copper foil for heat-dissipation described in any one of claims 1 to 19 of the scope of patent application.