JP2017123303A - Laminate sheet and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate sheet having a high quality metal plated layer formed on an insulating base material.SOLUTION: A laminate sheet 100 comprises a sheet-like insulating base material 10, a carbon nanotube layer 20 provided on the insulating base material 10, and a metal plated layer 30 provided on the carbon nanotube layer 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminate sheet and a method for producing the laminate sheet.

  Conventionally, a laminate sheet obtained by laminating a metal layer on a sheet-like insulating substrate having flexibility has been widely used as an electronic component such as a flexible circuit board or an electromagnetic shield film (for example, Patent Document 1). Such a laminate sheet is generally manufactured by a method in which a metal foil (for example, a copper foil) is attached to a resin sheet such as a polyimide film with an adhesive. Further, a technique for directly forming a metal layer on a resin sheet without using an adhesive has been studied. For example, a method of directly forming a metal thin film on a resin sheet along a predetermined pattern by an electroless plating method, a method of forming a metal thin film on a resin sheet, and then etching to form a predetermined pattern are known. ing.

JP 2008-094431 A

  However, the method of attaching a metal foil on a resin sheet with an adhesive has a limitation on the thickness of the metal foil to be used, and a thin laminate sheet cannot be formed (and corresponding to the recent reduction in thickness and weight). Is difficult). In addition, the method of directly forming a metal thin film on a resin film by an electroless plating method has an advantage that a metal thin film can be formed, but the electroless plating process is generally slow and produces a low-quality metal. There exists a problem that it becomes a laminated sheet easily and productivity is bad. It would be useful if a technique capable of efficiently forming a higher-quality metal layer on an insulating substrate was provided.

  An object of this invention is to provide the laminated sheet which can solve this subject. Another object of the present invention is to provide a laminate sheet manufacturing method capable of solving the above-mentioned problems.

  According to the present invention, a method for producing a laminate sheet comprising a sheet-like insulating base, a carbon nanotube layer provided on the insulating base, and a metal plating layer provided on the carbon nanotube layer Is provided. This manufacturing method comprises preparing a sheet-like insulating substrate; forming a carbon nanotube layer on the insulating substrate by applying a slurry containing carbon nanotubes on the insulating substrate; and Then, a metal plating layer is formed on the carbon nanotube layer by immersing the insulating base material with the carbon nanotube layer and the anode in a plating solution and passing an electric current between the carbon nanotube layer and the anode. Including. According to this manufacturing method, the surface of the insulating base material is made conductive by the carbon nanotube layer, and then electroplating is performed, so that a laminate sheet having a high-quality metal plating layer on the insulating base material can be efficiently obtained. Can be manufactured.

  In a preferred embodiment of the manufacturing method disclosed herein, the metal plating layer is formed on the carbon nanotube layer by transporting the insulating base material with a carbon nanotube layer in the longitudinal direction and passing through the plating solution. Form. In this way, the phenomenon in which the plating deposition amount is uneven depending on the location is eliminated or alleviated, and a metal plating layer having a more uniform thickness can be formed.

  In a preferred embodiment of the manufacturing method disclosed herein, a plating treatment tank is prepared in which the plating solution and an organic solvent that is not mixed with the plating solution are contained in a mutually separated state. And the said metal plating layer is formed on the said carbon nanotube layer by conveying the said insulating base material with a carbon nanotube layer to a longitudinal direction, and allowing the inside of the said plating liquid and the said organic solvent to pass through sequentially. In this way, a higher quality metal plating layer can be formed.

  In a preferred embodiment of the production method disclosed herein, the carbon nanotubes contained in the carbon nanotube layer are carbon nanotubes (CNTs) having 10 or less layers. A CNT having 10 layers or less (typically a single-walled CNT) has a higher conductivity than a CNT having more than 10 layers (typically a multilayer CNT), and thus is suitable as a CNT suitable for the purpose of the present invention. .

  In a preferred embodiment of the production method disclosed herein, the weight (weight per unit area) of the carbon nanotube layer per unit area (1 square centimeter) of the insulating substrate is 0.01 μg to 30 μg (for example, 1.5 μg). ~ 3.5 μg). Within the range of the weight of such a carbon nanotube layer, good conductivity can be imparted to the surface of the insulating substrate while suppressing the peeling of the carbon nanotube layer.

  Moreover, this invention provides a laminated body sheet as another side surface. The laminate sheet includes a sheet-like insulating base, a carbon nanotube layer provided on the insulating base, and a metal plating layer provided on the carbon nanotube layer. Since such a laminate sheet is provided with a high-quality metal plating layer on an insulating substrate, it is preferably used as a material suitable for various electronic component applications (for example, flexible substrates and electromagnetic shield films). Can do.

  In a preferred embodiment of the laminate sheet disclosed herein, the surface resistivity of the carbon nanotube layer is 200 Ω / sq or less. In this way, a higher quality metal plating layer can be formed on the carbon nanotube layer.

  In a preferred embodiment of the laminate sheet disclosed herein, the carbon nanotube layer substantially does not contain a resin binder. According to the aspect of the present invention, the shape of the carbon nanotube layer is maintained by the binding force resulting from the intermolecular force between the carbon nanotubes, and is bonded to the insulating substrate. Therefore, it is possible to realize a laminate sheet that does not substantially contain a resin binder. By not including a resin binder, such a laminate sheet can eliminate inconveniences such as the high resistance of the carbon nanotube layer due to the resin binder and a high-quality metal plating layer not being obtained.

  In a preferred embodiment of the laminate sheet disclosed herein, the metal plating layer has a thickness of 10 nm to 10000 nm (for example, 200 nm to 10000 nm). According to the aspect of the present invention, since the degree of freedom in selecting the thickness of the metal plating layer is high, metal plating layers corresponding to various thicknesses can be realized depending on the use of the laminate sheet.

  In a preferred embodiment of the laminate sheet disclosed herein, the metal plating layer includes Cu, Ni, Au, Sn, Ti, Ag, Co, Pd, W, Pt, Rh, Ir, Ru, Os, Fe, It contains at least one metal element selected from the group consisting of Mo and Mn. These metal elements can be suitably used as constituent components of a metal plating layer suitable for the purpose of the present invention.

  Moreover, this invention provides a flexible substrate (namely, flexible substrate which consists of a material and a shape which bends easily) as another side surface. This flexible substrate is configured using any laminate sheet disclosed herein. Since such a flexible substrate is configured using the laminate sheet, it can have higher performance.

  Moreover, this invention provides the electromagnetic wave shielding film as another side surface. This electromagnetic wave shielding film is comprised using any laminated sheet disclosed here. Since this electromagnetic shielding film is comprised using the said laminated body sheet, it can be a higher performance thing. Moreover, this invention provides a printed wiring board as another side surface. This printed wiring board is configured using any laminate sheet disclosed herein. In a preferred embodiment, the thickness of the metal plating layer provided in the printed wiring board may be 10 nm to 10000 nm (for example, 0.2 μm to 0.5 μm). Since such a printed wiring board is comprised using the said laminated body sheet, it can be a higher performance thing.

It is a figure which shows typically the cross section of the laminated body sheet which concerns on one Embodiment of this invention. It is a figure which shows typically the electrolytic plating apparatus which concerns on one Embodiment of this invention. It is a SEM image of a laminated body sheet. It is a figure which shows typically the electrolytic plating apparatus which concerns on other embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described. Note that matters other than the matters specifically mentioned in the present specification and necessary for the implementation of the present invention (for example, a method for producing an insulating base material or a carbon nanotube raw material) are known in the art. It can be grasped as a design matter of those skilled in the art based on The present invention can be carried out based on the contents disclosed in this specification and common technical knowledge in the field.

<Laminated sheet>
Drawing 1 is a figure showing typically the section of the layered product sheet concerning one embodiment of the present invention. The laminate sheet 100 disclosed herein includes a sheet-like insulating base material 10, a carbon nanotube layer (hereinafter also referred to as “CNT layer”) 20 provided on the insulating base material 10, and the above. And a metal plating layer 30 provided on the CNT layer 20.

<Insulating base material>
The insulating substrate 10 is not particularly limited as long as it is an insulating material, but preferably has a flexibility (a property of being bent and deformed by an external force) that can be easily bent. For example, as the insulating substrate 10, a resin sheet, paper, cloth, rubber sheet, a composite or laminate of these can be used. Especially, it is preferable to include a resin sheet or paper from the viewpoints of dimensional stability, workability, and the like. Preferred examples of the resin sheet include polyimide (PI); polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate; polyolefin resins such as polyethylene (PE) and polypropylene (PP); polyethylene naphthalate (PEN) and nylon (Nylon), polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), polyether sulfone (PES), polyvinyl alcohol (PVA), polycarbonate (PC), various acrylic resins such as polyarylate (PAR), Examples of the resin include urethane resin, fluorine resin, styrene resin, epoxy resin, and vinyl resin. Among the resin sheets, a PI sheet or a polyester sheet is preferable, and a PI sheet or a PET sheet is particularly preferable. As the paper, various kinds of paper made of general plant pulp, paper made of synthetic products (synthetic fibers), and the like can be used. Or you may use the board | substrate for common printed wiring boards, such as a paper phenol board | substrate, a paper epoxy board | substrate, a glass composite board | substrate, and a glass epoxy board | substrate. In the conventional mode in which a metal foil (for example, an electrolytic copper foil) is bonded to a substrate for such a printed wiring board, the thickness of the metal foil is limited. For example, a thin printed board having a thickness of less than 1 μm is formed. It was difficult. On the other hand, according to this aspect, even in such a printed circuit board, it is possible to suitably form a laminate sheet including a metal layer that is thinner (for example, about 0.5 μm or less, for example, about 0.2 μm) than in the past. . The sheet-like insulating substrate may have a single layer structure or a multilayer structure of two layers or three or more layers.

  The shape (outer shape) of the insulating substrate 10 may be a sheet shape. The sheet form referred to here is typically a thin form, and includes a flat form such as a long form, a film form, a tape form, and a plate form. Although the thickness of the insulating base material 10 can be suitably set according to the use of the laminate sheet, it is usually 5 μm to 2000 μm, preferably 10 μm to 200 μm.

<Carbon nanotube layer>
The carbon nanotube layer 20 is a layer containing carbon nanotubes (CNT), and is provided on the insulating substrate 10. The kind of CNT contained in the CNT layer 20 is not particularly limited. For example, it can be CNTs produced by various methods such as arc discharge, laser evaporation, and chemical vapor deposition (CVD). The CNT contained in the CNT layer 20 may be a single layer (for example, 1 to 3 layers, typically 1 layer or 2 layers), or a multilayer (for example, 4 layers to 200 layers, typically 4 layers to 4 layers). 60 layers). Further, the CNT layer 20 includes single-walled CNTs and multi-walled CNTs in an arbitrary ratio (the mass ratio of single-walled CNTs: multi-walled CNTs is, for example, 100: 0 to 50:50, preferably 100: 0 to 80:20). May be. The CNT contained in the CNT layer 20 is preferably 10 or less CNTs. Since CNTs having 10 layers or less have high conductivity, they are suitable as CNTs suitable for the purpose of the present invention. From the viewpoint of increasing the conductivity, it is more preferable that the CNT layer 20 is substantially composed of only 10 or fewer CNTs.

  It is appropriate that the average value of the aspect ratios (CNT length / diameter) of the CNTs contained in the CNT layer 20 is approximately 100 or more. The CNTs having the aspect ratio are easily entangled with each other, and the shape of the CNT layer 20 can be suitably maintained without being broken even when the laminate sheet is bent. Further, the CNT layer 20 is easily bound to the insulating substrate 10 by the binding force resulting from the intermolecular force. The average value of the aspect ratio of CNT is preferably 250 or more, more preferably 500 or more, still more preferably 800 or more, and particularly preferably 1000 or more. The upper limit of the aspect ratio of the CNT is not particularly limited, but from the viewpoint of handleability, ease of production, etc., it is appropriate to make it approximately 10,000 or less, preferably 8000 or less, more preferably 7000 or less, and even more preferably 6000. Hereinafter, it is particularly preferably 5000 or less. For example, CNT having an average aspect ratio of CNT of 100 to 8000 (preferably 3000 to 5000) is suitable. As the average aspect ratio of CNT (CNT length / diameter), a value typically obtained by measurement based on observation with an electron microscope (SEM) can be adopted.

  It is preferable that the average value of the diameter of the CNT is approximately 50 nm or less. The CNTs having the above-mentioned diameter are easily entangled with each other, and the shape of the CNT layer 20 can be suitably maintained without cracking even when the laminate sheet is bent. Further, the CNT layer 20 is easily bound to the insulating substrate 10 by the binding force resulting from the intermolecular force. The average value of the CNT diameter is preferably 40 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less. The lower limit of the diameter (average value) of the CNTs is not particularly limited, but is generally about 1 nm or more, preferably 1.2 nm or more. For example, CNTs having an average diameter of 1 nm to 10 nm (preferably 1.2 nm to 2 nm) are suitable.

As the CNT, those having an electric resistivity of 10 ⁻³ Ω · cm or less can be suitably used. Lower electrode resistance can be achieved by reducing the electrical resistivity of the CNTs. The electrical resistivity of the CNT is preferably 8 × 10 ⁻⁴ Ω · cm or less, more preferably 5 × 10 ⁻⁴ Ω · cm or less, and further preferably 3 × 10 ⁻⁴ Ω · cm or less. The lower limit of the electrical resistivity of the CNT is not particularly limited, but from the viewpoint of ease of production, etc., for example, 10 ⁻⁵ Ω · cm or more, typically 5 × 10 ⁻⁵ Ω · cm or more, for example, 10 ⁻⁴ Ω · cm. It may be cm or more.

  The weight of the CNT layer 20 per unit area (one square centimeter) of the insulating substrate 10 (that is, the basis weight in terms of solid content) is approximately 0.01 μg or more, for example, 0.1 μg or more, typically 1 μg or more, for example, It is preferably 1.5 μg or more. Thereby, it is possible to form a high-quality metal plating layer 30 by imparting good conductivity to the surface of the insulating substrate 10. The weight of the CNT layer 20 per unit area (1 square centimeter) of the insulating base material 10 is preferably 1.8 μg or more, more preferably 2.2 μg or more, and still more preferably from the viewpoint of imparting good conductivity. 2.5 μg or more. The upper limit of the weight of the CNT layer 20 is not particularly limited, but if the basis weight of the CNT layer 20 is too large, the CNT layer 20 may be easily peeled off from the insulating substrate 10. From the viewpoint of delamination suppression, the weight of the CNT layer 20 per unit area (one square centimeter) of the insulating base material 10 should be approximately 30 μg or less, for example, 15 μg or less, typically 3.5 μg or less. Preferably, it is 3.2 μg or less, more preferably 3 μg or less, and even more preferably 2.8 μg or less. For example, a laminate sheet in which the weight of the CNT layer 20 per unit area (one square centimeter) of the insulating base material 10 is 2.0 μg to 3.0 μg is highly compatible with good conductivity and suppression of peeling. It is preferable from the viewpoint.

  The surface resistivity of the CNT layer 20 is preferably approximately 200Ω / sq or less. In this way, it is possible to form a high-quality metal plating layer 30 by imparting good conductivity to the surface of the insulating substrate 10. The surface resistivity of the CNT layer 20 is preferably 180Ω / sq or less, more preferably 160Ω / sq or less. The lower limit of the surface resistivity of the CNT layer 20 is not particularly limited, but is generally 100 Ω / sq or higher, for example, 120 Ω / sq or higher, typically 140 Ω / sq or higher, from the viewpoint of ease of manufacture. As the surface resistivity of the CNT layer 20, a value measured by a four-point probe method using a commercially available surface resistance measuring device can be adopted.

  In a preferred embodiment, the CNT layer 20 does not substantially contain a resin binder. Specific examples of the resin binder here include polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), polyacrylonitrile (PAN), fluororesin (for example, polyvinyl alcohol (PVA), polytetrafluoroethylene (PTFE). ), Tetrafluoroethylene-hexafluoropropylene copolymer (FEP), etc.), rubbers (vinyl acetate copolymer, styrene butadiene copolymer (SBR), acrylic acid-modified SBR resin (SBR latex), etc.), cellulose Based polymers (carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC)) and the like. If the resin binder is contained in the CNT layer 20, there is a problem that the resistance increases and a high-quality metal plating layer cannot be obtained. On the other hand, according to the said structure, since the CNT layer 20 does not contain a resin binder substantially, such inconvenience can be avoided.

<Metal plating layer>
The metal plating layer 30 is a layer obtained by electrolytic plating described later, and is provided on the CNT layer 20 described above. The metal constituting the metal plating layer 30 is not particularly limited as long as it is a metal conventionally used for this type of metal plating layer. For example, the constituent metal elements of the metal plating layer 30 are copper (Cu), nickel (Ni), gold (Au), tin (Sn), titanium (Ti), silver (Ag), cobalt (Co), palladium (Pd ), Tungsten (W), platinum (Pt), rhodium (Rh), iridium (Ir), ruthenium (Ru), osmium (Os), iron (Fe), molybdenum (Mo) and manganese (Mn) 1 type or the combination of 2 or more types is preferable. Among these, any 1 type or the combination of 2 or more types among Cu, Ni, and Au is preferable.

  In a preferred embodiment, the metal plating layer 30 and the CNT layer 20 are arranged in a state separated into two layers. That is, the metal plating layer 30 is laminated on the CNT layer 20. The thickness of the metal plating layer 30 may be typically 10 nm to 10000 nm (10 μm), such as 200 nm to 10000 nm, such as 300 nm to 5000 nm, typically 400 nm to 2000 nm (2 μm). According to the technique disclosed here, since the degree of freedom in selecting the thickness of the metal plating layer 30 is high, the metal plating layer 30 corresponding to various thicknesses can be formed according to the use of the laminate sheet 100. For example, a thin metal plating layer 30 of about 10 nm to 200 nm can be suitably realized. Moreover, the thick metal plating layer 30 of about 10000 nm can be suitably realized.

<Method for producing laminate sheet>
The laminate sheet 100 disclosed herein is provided with a sheet-like insulating base material 10; a slurry for forming a CNT layer containing carbon nanotubes is applied on the insulating base material 10 (typically, coating, The CNT layer 20 is formed on the insulating substrate 10 by drying); and the insulating substrate 10 with the CNT layer 20 and the anode are immersed in a plating solution, and the CNT layer 20 and the CNT layer 20 are immersed in the plating solution. Forming a metal plating layer 30 on the CNT layer 20 by passing an electric current between the anode and the anode.

  The CNT layer forming slurry may contain, for example, CNT and a liquid medium. The liquid medium preferably has a solvent content of 95% by mass or more (in other words, the component other than the solvent, that is, the non-volatile content is less than 5% by mass), and the above ratio is 99% or more. Some liquid media are more preferred. It may be a liquid medium that does not substantially contain non-volatile components. The composition of the solvent constituting the liquid medium can be appropriately selected according to the purpose and embodiment, and can be, for example, water, an organic solvent, or a mixed solvent thereof. It is preferable to use a solvent that can be easily removed by heating (for example, in a temperature range of 200 ° C. or lower, more preferably 120 ° C. or lower). Examples of the organic solvent include lower alcohols (for example, alcohols having about 1 to 4 carbon atoms such as methanol and ethanol), lower ketones (acetone, methyl ethyl ketone, and the like), lower alcohol acetates (for example, ethyl acetate), and the like. It can be any one or more solvents selected.

  The slurry for forming a CNT layer disclosed herein has, for example, a form in which the solid content (non-volatile content; NV) is 0.01% by mass to 5% by mass and the balance is a liquid medium. It can be preferably implemented. A form in which the NV is 0.05% by mass to 0.1% by mass is more preferable.

  The CNT layer forming slurry may contain various additives other than those described above without departing from the object of the present invention. As a suitable example of an additive, surfactant, an antifoamer, antioxidant, a dispersing agent, a viscosity modifier etc. are mentioned, for example.

  By applying an appropriate amount of the slurry for forming the CNT layer on the insulating base material 10 and drying, the insulating base material 10 with the CNT layer 20 in which the CNT layer 20 is formed on the insulating base material can be obtained. it can. There is no restriction | limiting in particular as a method of apply | coating the said slurry for CNT layer formation on the insulating base material 10, For example, well-known application methods, such as spray spraying and screen printing, are employable. If necessary, the above coating operation may be repeated a plurality of times (for example, 2 to 10 times, typically 3 to 5 times). The removal of the liquid medium can also be performed by a conventional general drying means (for example, heat drying or vacuum drying). The heating temperature for drying the slurry can be appropriately set in consideration of the composition of the liquid medium (particularly the boiling point of the solvent). Usually, the drying temperature is preferably about 40 ° C. to 250 ° C. (for example, about 60 ° C. to 150 ° C.). After drying, if necessary, a heat treatment or a washing treatment may be performed to remove the additive contained in the CNT layer 20.

  FIG. 2 is a schematic diagram showing an electroplating apparatus 40 that embodies a metal plating layer forming process according to the present embodiment. The electrolytic plating apparatus 40 includes a transfer device 42, a plating treatment tank 44, an anode 46, and a cathode 48.

  The transport device 42 is a device that transports the insulating base material 10 with the CNT layer 20. The insulating base material 10 with the CNT layer 20 is transported along a predetermined transport path by the transport device 42. An arrow F in the figure indicates the transport direction of the insulating base material 10 with the CNT layer 20. In this embodiment, the transport device 42 includes a transport roller 42. As shown in FIG. 2, the insulating base material 10 with the CNT layer 20 is subjected to an electrolytic plating process while being conveyed in the longitudinal direction by a conveying roller 42.

  The plating tank 44 is a tank in which a plating solution 44a is stored. In this embodiment, an organic solvent 44b that is not mixed with the plating solution 44a is stored below the plating solution 44a. That is, in the plating tank 44, the plating solution 44a and the organic solvent 44b are accommodated in a state of being separated from each other (here, in a state of being divided into upper and lower layers). Here, the plating solution 44a constitutes the upper layer, and the organic solvent 44b constitutes the lower layer.

  The plating solution 44a accommodated in the plating treatment tank 44 contains a metal element. This metal element can typically be in the form of a metal ion. The plating formed by the electrolytic plating apparatus 40 is a metal plating containing this metal element (that is, a plating made of a single metal element or an alloy containing a metal element). As described above, the metal element can be appropriately selected according to the use of the laminate sheet.

  Examples of the solvent used in the plating solution 44a disclosed herein include water or a mixed solvent mainly composed of water. As a solvent other than water constituting such a mixed solvent, one or more organic solvents (lower alcohol, lower ketone, etc.) that can be uniformly mixed with water can be appropriately selected and used. Examples of lower alcohols that can be uniformly mixed with water include alcohols having high compatibility with water such as methanol, ethanol, propanol, 2-propanol, n-butanol, hexanol, ethylene glycol, diethylene glycol, and triethylene glycol. . Examples of lower ketones that can be uniformly mixed with water include acetone, methyl ethyl ketone, diethyl ketone, and 4-methyl-2-butanone. For example, it is preferable to use a mixed solvent in which 50% by mass or more (more preferably 60% by mass or more, more preferably 70% by mass or more) of the mixed solvent is water. By using such a mixed solvent, a metal element (typically in the form of metal ions) can be stably retained in the plating solution.

  The plating solution 44a is a known additive such as a plating deposition accelerator, a surfactant, an antioxidant, a viscosity adjuster, a pH adjuster, and a preservative, as long as the effects of the present invention are not significantly hindered. You may further contain as needed.

  The organic solvent 44b accommodated in the plating tank 44 is preferably an organic solvent that is liquid at room temperature (for example, 25 ° C.) and that does not substantially mix with the above-described plating solution 44a (ie, is hydrophobic). . Moreover, it is preferable that it is an organic solvent which can be stably hold | maintained in the lower layer of the plating solution 44a (namely, specific gravity is larger than the plating solution 44a). Furthermore, it is preferable to use an electrochemically stable organic solvent that does not undergo decomposition or redox reaction during plating. An organic solvent satisfying such conditions can be used without particular limitation. Examples of the organic solvent include chlorine such as carbon disulfide, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, 1,2, dichloroethylene, and trichloroethylene. System solvents are exemplified. Since these organic solvents are liquid at room temperature (for example, 25 ° C.) and exhibit substantially the property that they are hardly mixed with the plating solution 44a, they can be suitably used as organic solvents suitable for the purpose of the present invention. Of these, the use of carbon disulfide is preferred.

  The organic solvent 44b may be added with known additives such as surfactants, antioxidants, viscosity modifiers, pH adjusters, preservatives, and the like as necessary, as long as the effects of the present invention are not significantly hindered. You may contain.

  The anode (anode) 46 is disposed in the plating solution 44 a of the plating treatment tank 44. The anode 46 is made of a thin plate of a conductive material, and is electrically connected to a power source (not shown) by a lead wire (not shown). The power source is, for example, a DC power source, and energizes between the anode 46 and the cathode 48 (CNT layer 20).

  The cathode (cathode) 48 is disposed on the back side of the surface where the transport roller 42 contacts the insulating base material 10 with the CNT layer 20. In the example shown in FIG. 2, the transport roller 42 transports the insulating substrate 10 with the CNT layer 20 with the surface on which the CNT layer 20 is formed facing the cathode 48, and applies the cathode 48 to the CNT layer 20. . The cathode 48 is made of a conductive material (for example, stainless steel) and is electrically connected to a power source (not shown) by a lead wire (not shown). According to the technology disclosed herein, the minimum distance from the cathode 48 to the plating solution 44a can be set to, for example, 20 mm or less (for example, 5 mm to 15 mm). In the laminate sheet 100 manufactured in such a manner that the minimum distance from the cathode 48 to the plating solution 44a is in the above numerical range, the application effect of the technique disclosed herein can be exhibited particularly well.

  In order to perform electroplating in the electroplating apparatus 40 having the above-described configuration, as described above, a plating tank 44 containing a plating solution 44a and an organic solvent 44b that is not mixed with the plating solution 44a is prepared. To do. Then, the insulating base material 10 with the CNT layer 20 is sequentially passed through the plating solution 44a and the organic solvent 44b while being conveyed in the longitudinal direction by the conveying roller 42. Further, the transport roller 42 transports the insulating substrate 10 with the CNT layer 20 with the surface on which the CNT layer 20 is formed facing the cathode 48, and the cathode 48 is applied to the CNT layer 20. In this state, when the current is passed between the cathode 48 and the anode 46 and a current is passed between the CNT layer 20 and the anode 46, the insulating base material 10 with the CNT layer 20 passes through the plating solution 44a. In the meantime, metal deposits on the CNT layer 20. By this deposition, a metal plating layer 30 is formed on the CNT layer 20.

  Here, in the conventional mode in which the entire insulating base material 10 with the CNT layer 20 is immersed in the plating solution 44a without carrying the insulating base material 10 with the CNT layer 20 in the longitudinal direction, the cathode 48 is used. The current density distribution is biased depending on the distance from (typically, the closer the distance from the cathode 48, the lower the resistance value and the easier the current flows). Forming the metal plating layer 30 tends to be difficult. On the other hand, according to the electrolytic plating apparatus 40, the insulating base material 10 with the CNT layer 20 is conveyed in the longitudinal direction and sequentially passed through the plating solution 44a and the organic solvent 44b, so that the metal is deposited on the CNT 20 layer. Since the plated layer 30 is formed, the distance between the portion to be plated (the portion immersed in the plating solution 44a) of the insulating substrate 10 with the CNT layer 20 and the cathode 48 is kept substantially constant. Therefore, the phenomenon that the current density distribution is biased depending on the distance from the cathode 48 (and hence the plating deposition amount is biased depending on the location) is eliminated or alleviated, and the metal plating layer 30 having a more uniform thickness is formed. be able to.

<Application>
As described above, the laminate sheet 100 disclosed herein has the metal plating layer 30 having a high quality and a uniform thickness on the sheet-like insulating substrate 10. Therefore, it can be preferably used as a material suitable for various electronic component applications. The electronic component can be, for example, a flexible board (for example, a flexible circuit board) used for wiring to a movable part to be bent or three-dimensional wiring. Or the said laminated body sheet 100 can be used for the electromagnetic shielding film which shields electromagnetic waves etc., the laminated board for printed wiring boards, etc. In such applications, it is particularly meaningful to apply the technology disclosed herein.

  When patterning the metal plating layer 30 using the laminate sheet 100 as a flexible substrate or the like, after the CNT layer 20 and the metal plating layer 30 are sequentially formed on the insulating base material 10, for example, by laser irradiation. A method of etching (removing) a part of the CNT layer 20 and the metal plating layer 30 to form a predetermined pattern can be preferably employed. Instead of laser irradiation, the CNT layer 20 may be etched by plasma (vacuum plasma or atmospheric pressure plasma) or ultraviolet ozone treatment. In this case, for example, the metal plating layer is etched by a method similar to a general printed circuit board manufacturing method (typically, a resist is applied to the surface of the metal plating layer, exposed to a predetermined pattern through a mask, and then developed. A part of the resist is removed, the exposed metal plating layer is wet-etched or dry-etched), and the exposed underlying CNT layer is then removed by plasma or ultraviolet ozone treatment. Alternatively, the underlying CNT layer 20 may be formed along a predetermined pattern on the insulating substrate 10 using a mask or the like, and the metal plating layer 30 may be formed thereon by the electrolytic plating process described above. The laminate sheet 100 disclosed herein may include a form in which the CNT layer 20 and the metal plating layer 30 are formed along a predetermined pattern.

  Next, some examples relating to the present invention will be described, but the present invention is not intended to be limited to those shown in the examples.

  A CNT layer forming slurry was prepared by mixing 10 or less layers of CNTs having an average aspect ratio of 5000 and water as a liquid medium. Insulation with a CNT layer 20 in which the CNT layer 20 is provided on one side of the insulating substrate 10 by applying this slurry onto a long sheet-like PI sheet (insulating substrate) 10 by spraying and drying. The base material 10 was produced. The weight (weight per unit area) of the CNT layer per unit area (1 square centimeter) of the insulating base was adjusted to be about 2.3 μg.

  Next, by using the electrolytic plating apparatus 40 as shown in FIG. 2, the insulating base material 10 with the CNT layer 20 is conveyed in the longitudinal direction and sequentially passed through the plating solution 44 a and the organic solvent 44 b, A metal plating layer 30 was formed on the CNT layer 20. Here, the metal constituting the metal plating layer 30 was copper, and the film thickness of the metal plating layer 30 was 10 nm to 200 nm. In this way, a laminate sheet in which the CNT layer 20 and the metal plating layer 30 were sequentially formed on the insulating substrate 10 was obtained.

  The surface of the obtained laminate sheet was observed with a scanning electron microscope (SEM). The results are shown in FIG. As shown in FIG. 3, it was confirmed that the CNT layer and the metal plating layer were formed on the insulating base material in a state of being separated into two layers. Further, in order to evaluate the degree of adhesion of the obtained laminate sheet, the laminate sheet was bent vertically. As a result, peeling of the CNT layer and the metal plating layer was not observed. That is, according to this example, it was confirmed that a laminate sheet in which the CNT layer and the metal plating layer were firmly fixed on the insulating base material was manufactured without substantially using a resin binder.

  As mentioned above, although this invention was demonstrated by suitable embodiment, such description is not a limitation matter and of course various modifications are possible.

  For example, in the above-described embodiment, the case where the plating bath 44 containing the plating solution 44a and the organic solvent 44b not mixed with the plating solution 44a in a state of being separated from each other is used. The configuration is not limited to this. For example, as shown in FIG. 4, the plating solution 44 a is contained alone in the plating treatment tank 44, and the insulating base material 10 with the CNT layer 20 being conveyed is pressed by the pressing roller 42 a, and a part of the plating solution 44 a is obtained. You may comprise so that it may be immersed in. Even in such a case, since the distance between the portion to be plated (the portion immersed in the plating solution 44a) of the insulating substrate 10 with the CNT layer 20 and the cathode 48 is kept constant, the plating deposition amount is uneven depending on the location. The phenomenon that occurs is eliminated or alleviated, and the metal plating layer 30 having a more uniform thickness can be formed.

  Moreover, although embodiment mentioned above illustrated the case where the CNT layer 20 and the metal plating layer 30 were formed in the single side | surface of the insulating base material 10, it is not limited to this. For example, in the laminate sheet 100, the CNT layer 20 and the metal plating layer 30 may be formed on both surfaces of the insulating base material 10, respectively. Even in this aspect, the above-described operational effects can be obtained.

DESCRIPTION OF SYMBOLS 10 Insulating base material 20 Carbon nanotube (CNT) layer 30 Metal plating layer 40 Electrolytic plating apparatus 42 Conveyance roller 44 Plating tank 44a Plating solution 44b Organic solvent 46 Anode 48 Cathode 100 Laminate sheet

Claims (15)

A sheet-like insulating substrate;
A carbon nanotube layer provided on the insulating substrate;
A laminate sheet comprising a metal plating layer provided on the carbon nanotube layer.   The laminate sheet according to claim 1, wherein the carbon nanotubes contained in the carbon nanotube layer are ten or fewer carbon nanotubes.   The laminate sheet according to claim 1 or 2, wherein a weight of the carbon nanotube layer per unit area (1 square centimeter) of the insulating substrate is 0.01 µg to 30 µg.   The laminate sheet according to any one of claims 1 to 3, wherein a surface resistivity of the carbon nanotube layer is 200 Ω / sq or less.   The laminate sheet according to any one of claims 1 to 4, wherein the carbon nanotube layer does not substantially contain a resin binder.   The laminate sheet according to any one of claims 1 to 5, wherein the metal plating layer has a thickness of 10 nm to 10000 nm.   The metal plating layer is at least one metal selected from the group consisting of Cu, Ni, Au, Sn, Ti, Ag, Co, Pd, W, Pt, Rh, Ir, Ru, Os, Fe, Mo, and Mn. The laminate sheet according to any one of claims 1 to 6, comprising an element.   The flexible substrate which uses the laminated sheet as described in any one of Claims 1-7.   The electromagnetic shielding film which uses the laminated body sheet as described in any one of Claims 1-7.   The printed wiring board which uses the laminated body sheet as described in any one of Claims 1-7. A method for producing a laminate sheet comprising a sheet-like insulating substrate, a carbon nanotube layer provided on the insulating substrate, and a metal plating layer provided on the carbon nanotube layer,
Preparing a sheet-like insulating substrate;
Forming a carbon nanotube layer on the insulating substrate by applying a slurry containing carbon nanotubes on the insulating substrate; and
A metal plating layer is formed on the carbon nanotube layer by immersing the insulating base material with the carbon nanotube layer and the anode in a plating solution, and passing a current between the carbon nanotube layer and the anode. ;
A method for producing a laminate sheet.   The manufacturing method of Claim 11 which forms the said metal plating layer on the said carbon nanotube layer by conveying the said insulating base material with a carbon nanotube layer to a longitudinal direction, and allowing the inside of the said plating liquid to pass through. Preparing a plating tank containing the plating solution and an organic solvent which is not mixed with the plating solution, separated from each other;
The metal plating layer is formed on the carbon nanotube layer by transporting the insulating base material with a carbon nanotube layer in a longitudinal direction and sequentially passing through the plating solution and the organic solvent. Or the manufacturing method of 12.   The carbon nanotube contained in the said carbon nanotube layer is a manufacturing method as described in any one of Claims 11-13 which is a carbon nanotube of 10 layers or less. The manufacturing method according to any one of claims 11 to 14, wherein a weight of the carbon nanotube layer per unit area (1 square centimeter) of the insulating substrate is 0.01 μg to 30 μg.