JP6547449B2 - LAMINATE AND METHOD FOR MANUFACTURING THE SAME - Google Patents

Description

  The present invention relates to a laminate having a carbon nanotube-containing layer comprising carbon nanotubes and a resin, and a method for producing the same.

  Carbon nanotubes, which are cylindrical carbon materials with a diameter of several nanometers to several tens of nanometers, have high conductivity and mechanical strength, so fuel cells, electrodes, electromagnetic shielding materials, conductive resins, field emission displays ( As functional materials such as members for FEDs and storage materials of various gases including hydrogen, their application to a wide range of fields such as electronics and energy fields is expected.

  Among them, many studies have been conducted on conductive transparent films using carbon nanotubes. For example, what laminated | stacked the carbon nanotube electrically conductive film and the transparent protective film on the single side | surface of a transparent base material is proposed. (For example, refer to patent document 1)

  Moreover, the manufacturing method of the electroconductive transparent film which coats a resin solution, after coating a carbon nanotube dispersion on the base-material surface and making it dry, is also proposed. (See Patent Document 2)

On the other hand, there are few examples using carbon nanotubes as a coloring material, and in order to obtain jet-black resin coated products, films, and molded products, carbon black uniformly dispersed in resin solution and solid resin has been used. . (See Patent Documents 3 and 4) However, in the means, the lightness (L ^* ) is in the high (grey / white) direction, and the chromaticity (a *, b *) is in the positive direction (+ a *: red, + b) *: Yellow), and it was difficult to express jet blackness such as so-called "piano black" or "wet feather color of crow".

  In addition, the color tone of a molded article using carbon black tends to be different depending on the primary particle diameter of carbon black. Specifically, when carbon black having a small primary particle diameter is used, it has bluish but blackness decreases. As described above, since black coloration has a trade-off relationship between blackness and blueness, it has been difficult to reproduce a jet black color tone that is bluish and has a high degree of blackness.

  Therefore, the blackness is prepared by changing the colloidal properties such as carbon black particle size and agglomerated particle size, or subjecting the carbon black to surface treatment such as ozone oxidation or nitric acid oxidation to change the dispersion state in the dispersion. Has been done. (Refer to Patent Documents 5, 6, and 7) There is also a method of further adding an organic pigment such as phthalocyanine blue in order to obtain bluish color in addition to black. However, the degree of blackness decreases with the addition of the organic pigment, and when the molded body is observed in direct sunlight, there is a problem that a so-called bronzing phenomenon occurs in which a reddish color is observed.

JP, 2010-192186, A Japanese Patent Publication No. 2004-526838 JP 2001-179176 A JP, 2004-098033, A JP-A-6-122834 JP-A-6-136287 JP 2008-285632 A

  The present invention solves the above-mentioned conventional problems, and an object thereof is to provide a laminate which is bluish and has excellent blackness with high blackness.

  MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, the present inventors discover that the laminated body of the resin composition excellent in jet-blackness can be obtained by laminating | stacking the resin composition containing a carbon nanotube and resin. The present invention has been achieved.

That is, the present invention is a laminate having a carbon nanotube-containing layer comprising a carbon nanotube and a resin, and a clear layer, wherein L ^{* of} the laminate measured from the plane direction of the clear layer is 26 or less and b ^The present invention relates to a laminate characterized in that ^* is −10 or more and 0.3 or less, the carbon nanotube-containing layer is formed by a method other than coating, and the clear layer is a transparent resin or glass.
(However, L ^* and b ^* represent values in the L ^* a ^* b ^* color system specified in JIS Z8729.)

  In addition, the present invention relates to the laminate, wherein the method other than coating is any method of extrusion molding, injection molding, blow molding, compression molding, transfer molding, inflation molding, or calendar molding.

  Moreover, this invention relates to the said laminated body whose fiber diameter of a carbon nanotube is 8-25 nm.

  The present invention relates to the laminate, wherein the amount of carbon nanotubes in the carbon nanotube-containing layer is 0.1 to 10% by mass.

  Moreover, this invention relates to the said laminated body whose film thickness of a carbon nanotube containing layer is 50 micrometers-5 mm.

  This invention relates to the said laminated body whose film thickness of a clear layer is 5 micrometers-40 micrometers.

  Moreover, this invention relates to the said laminated body whose average reflectance in wavelength 380-780 nm of the laminated body measured from the surface direction of a clear layer is 10% or less.

The present invention is a method for producing a laminate having a carbon nanotube-containing layer comprising a carbon nanotube and a resin, and a clear layer, wherein the L ^{* of} the laminate measured from the surface direction of the clear layer is 26 or less The present invention relates to a method for producing the laminate, wherein b ^* is −10 or more and 0.3 or less, the clear layer is a transparent resin or glass, and the carbon nanotube-containing layer is formed by a method other than coating.

  The present invention also relates to the method for producing the laminate, wherein the method other than coating is any of extrusion molding, injection molding, blow molding, compression molding, transfer molding, inflation molding, or calendar molding.

  By using the laminate of the present invention, a laminate excellent in jet clarity can be obtained. Thus, it is possible to use the laminate obtained by the present invention in various application fields where high jetness is required.

Hereinafter, the laminate (a) of the present invention will be described in detail.
The laminate (a) of the present invention is a laminate having a carbon nanotube-containing layer comprising carbon nanotubes and a resin, and a clear layer, wherein L ^{* of} the laminate measured from the surface direction of the clear layer is The laminate is characterized in that 26 or less and b ^* is -10 or more and 0.3 or less, the carbon nanotube-containing layer is formed by a method other than coating, and the clear layer is a transparent resin or glass.

Furthermore, it is preferable that a ^{* of} the laminate measured from the surface direction of the clear layer of the laminate (a) is −2 or more and 6 or less, and a laminate exhibiting such L ^* , a ^* and b ^* In the case of the above, a laminate (a) excellent in jet blackness is obtained.

Here, L ^* , a ^* and b ^* represent values in the L ^* a ^* b ^* color system specified in JIS Z8729, and a color difference meter (from the surface direction of the clear layer of the laminate (a) It is obtained by measurement using NIPPON DENSHOKU Co., Ltd. SpectroColorMeter SE2000).

  In the laminate of the present invention, the carbon nanotube-containing layer and the clear layer do not have to be laminated in close contact, but it is more excellent in jet blackness if these layers are laminated in close contact with each other. A laminate (a) is obtained.

Generally, the smaller L ^* is, the higher the blackness (the lower the lightness). The closer a ^* and b ^* are to zero (0), the blacker the hue. Also, it can be said that bluish (blue) has a stronger hue as b ^* is more negative. Therefore, from the viewpoint of jet blackness, it is considered that jet blackness is high when it is black having a slight bluish color (blue color), so the above numerical range is considered to be preferable.

  The average reflectance at a wavelength of 380 to 780 nm of the laminate measured from the clear layer (e) is preferably 10% or less, and more preferably less than 5%. If it is such a range in particular, a laminate excellent in jet blackness can be obtained.

The carbon nanotube-containing layer (b) of the present invention will be described in detail.
The carbon nanotube-containing layer (b) of the present invention is a carbon nanotube-containing layer (b) comprising at least the carbon nanotubes (c) and the resin (d), and the carbon nanotube-containing resin composition (b ′) is applied It is characterized in that it is formed by any other method.
Specific preferred examples of the method include extrusion molding, injection molding, blow molding, compression molding, transfer molding, film forming such as T-die molding and inflation molding, and calendar molding.
For example, in the case of injection molding, the carbon nanotube-containing resin composition (b ') is melt-kneaded and then injected into a mold to form a carbon nanotube-containing layer (b) of an arbitrary shape.

  The thickness of the carbon nanotube-containing layer (b) is preferably 50 μm to 5 mm, and more preferably 100 μm to 3 mm.

The carbon nanotube (c) used for the carbon nanotube-containing layer (b) of the present invention will be described.
The carbon nanotube (c) has a cylindrical shape obtained by winding one surface of graphite, and the single-layer carbon nanotube has a structure in which the graphite layer is wound in one layer, and is wound with two or more layers. Multi-walled carbon nanotubes may be used or may be a mixture thereof, but multi-walled carbon nanotubes are preferable in terms of cost and coloring effect. Moreover, the side wall of carbon nanotube (c) does not have a graphite structure, but a carbon nanotube (c) having an amorphous structure can also be used.

  The shape of the carbon nanotube (c) may be any shape such as needle shape, cylindrical tube shape, fish bone shape (fish bone, cup laminated type), card shape (platelet), coil shape, etc. Good. Specifically, for example, graphite whiskers, filamentous carbon, graphite fibers, ultrafine carbon tubes, carbon tubes, carbon fibrils, carbon microtubes, carbon nanofibers and the like can be mentioned. It can be used in the form which combined 1 type, or 2 or more types as these forms. The present invention is preferably in a form other than fish bone (fish bone, cup laminated type), card (platelet), or coil. In the case of fish-bone-like or card-like, cutting of the carbon nanotube (b) from the laminated surface (x-y plane) of the cup / cardlike graphite sheet occurs due to shear stress generated at the time of production of the resin composition / molded product, The sufficient network structure can not be formed in the resin, and the light confinement effect may be reduced, which may lead to a decrease in blackness. Also in the case of a coil, the three-dimensional structure is likely to be broken during manufacture, and the coloring effect may be reduced.

  The carbon nanotube (c) of the present invention can generally be produced by a laser ablation method, arc discharge method, thermal CVD method, plasma CVD method, combustion method, etc. However, carbon nanotubes (b) produced by any method may be used. . For example, a carbon nanotube (c) can be produced by catalytic reaction of a hydrocarbon and / or an alcohol as a carbon source at 500 to 1000 ° C. in an atmosphere having an oxygen concentration of 1% by volume or less using a catalyst it can.

  The raw material gas as a carbon source of the carbon nanotube (c) may be any conventionally known one. For example, as a gas containing carbon, hydrocarbons such as methane, ethylene, propane, butane, acetylene and the like, carbon monoxide, alcohol Although it is possible to use, etc., it is desirable to use a hydrocarbon or alcohol, particularly for reasons of ease of use.

  The catalyst may be produced, as required, after activation under a reducing gas atmosphere, or by contact reaction with a source gas as a carbon source in an atmosphere having an oxygen concentration of 1% by volume or less together with the reducing gas preferable. The atmosphere having an oxygen concentration of 1% by volume or less is not particularly limited, but is preferably an atmosphere of a rare gas such as argon gas or an inert gas such as nitrogen gas. As the reducing gas used for activation, hydrogen, ammonia and the like can be used, but hydrogen is particularly preferable.

  Various known metal oxides can be used as the catalyst. For example, the catalyst which combined the metal containing active ingredients, such as cobalt, nickel, and iron, and the metal containing supporting components, such as magnesium and aluminum, is mentioned.

  The fiber diameter of the carbon nanotube (c) is preferably 1 to 500 nm, and more preferably 8 to 25 nm, from the viewpoint of easiness of dispersion and hue.

  For the fiber diameter of carbon nanotube (c), observe the carbon nanotube (c) with a scanning transmission electron microscope, select 100 arbitrary carbon nanotubes (c) in the observation photograph, and measure the outer diameter of each. It can measure by calculating the average particle diameter (nm) of a carbon nanotube (c) by calculating | requiring the number average value.

  The fiber length of the carbon nanotube (c) is preferably 0.1 to 150 μm, and more preferably 1 to 10 μm, from the viewpoint of easiness of dispersion and hue.

  85 mass% or more is preferable in 100 mass% of carbon nanotubes (c), as for carbon purity of carbon nanotube (c), 90 mass% or more is more preferable, and 95 mass% or more is more preferable.

  In the present invention, carbon nanotubes (c) are generally present as secondary particles. The secondary particle shape may be, for example, a state in which carbon nanotubes (c), which are general primary particles, are intricately entangled, or may be an aggregate of straight carbon nanotubes (c) which are easily loosened. . Secondary particles, which are aggregates of linear carbon nanotubes (c), are preferable because they have better dispersibility than entangled ones.

  The carbon nanotube (c) may be a surface-treated carbon nanotube derivative or a carbon nanotube derivative having a functional group such as a carboxyl group. In addition, carbon nano nanotubes (c) in which an organic compound, a metal atom, fullerene or the like is encapsulated can be used.

  The amount of carbon nanotubes (c) in the carbon nanotube-containing layer (b) may be appropriately selected depending on the application, but is preferably 0.01 to 30% by mass, more preferably 0.05 to 20% by mass, More preferably, it is in the range of 0.1 to 10% by mass. If it is such a range in particular, a laminate excellent in jet blackness can be obtained.

  In the carbon nanotube-containing layer (b), carbon nanotubes (c) and carbon black can be used in combination as long as the object of the present invention is not impaired. Specific examples of carbon black include partial oxidation of hydrocarbons such as ketjen black, acetylene black, furnace black, channel black and naphtha in the presence of hydrogen and oxygen to produce a synthesis gas containing hydrogen and carbon monoxide And carbon black which is by-produced during the reaction, or carbon black obtained by oxidizing or reducing this. These carbon blacks may be used alone or in combination of two or more. Further, from the viewpoint of improving blackness, carbon black having an average particle diameter of 20 nm or less and a DBP oil absorption of 80 ml / 100 g or less is preferably used. Further, in the present invention, DBP oil absorption is a measure of complex aggregation form (structure) by chemical or physical bonding between carbon black particles, and dibutyl phthalate (DBP) which can be included per 100 g of carbon black. It represents the amount (ml).

  The average particle size of the carbon black is determined by the same method as the fiber diameter of the carbon nanotube (c). Specifically, carbon black is observed by a scanning transmission electron microscope, 100 arbitrary carbon blacks are selected in the observation photograph, the outer diameter of each is measured, and the carbon black is obtained by calculating its number average value. The average particle size of can be calculated.

  The amount of carbon black used is preferably 1 to 100 parts by weight, more preferably 1 to 50 parts by weight, and still more preferably 1 to 25 parts by weight with respect to 100 parts by weight of the carbon nanotube (c). On the other hand, if it exceeds 100 parts by weight, the blackness and blueness of the molded product may be reduced. When the bluishness decreases and the redness increases, it is difficult to obtain a laminate excellent in jet blackness.

The resin (d) used for the carbon nanotube-containing layer (b) of the present invention will be described.
The resin (d) used in the present invention plays a role as a binder for dispersing and stabilizing the carbon nanotube (c) and immobilizing it.

  The resin (d) used in the present invention is a thermoplastic resin which has the ability to disperse and stabilize carbon nanotubes and is not particularly limited as long as it can be molded, but it is a thermoplastic resin that can be molded by heating and melting. Is preferred. The thermoplastic resin is, for example, polyolefin resin such as polyethylene (PE) resin, polypropylene (PP) resin, polystyrene resin, polyphenylene ether resin, polyethylene terephthalate (PET) resin, acrylonitrile-butadiene-styrene copolymer resin, Polycarbonate resins, polyamide resins, polyacetal resins, polyester resins, polyvinyl chloride resins, acrylic resins, polyetherimide resins and the like can be mentioned. The thermoplastic resin (A) can be used alone or in combination of two or more.

The method for producing a carbon nanotube-containing resin composition (b ′) from the carbon nanotubes (c) and the resin (d) of the present invention is not particularly limited, but Henschel, which is a general high-speed shear mixer The mixture is introduced into a mixer or super mixer and mixed, and then melt-kneaded using a two-roll, three-roll, pressure kneader, Banbury mixer, single-screw kneader, twin-screw kneader, etc. It can be obtained by molding.
In addition, if necessary, additives such as, for example, an ultraviolet absorber, an antioxidant, a crosslinking agent, and a dispersing agent can be appropriately blended in a range that does not impair the object of the present invention.

The clear layer (e) of the present invention will be described in detail.
The clear layer (e) of the present invention has transparency to such an extent that the carbon nanotube layer (b) can be visually recognized. Specifically, transparent resin, glass and the like can be mentioned. As transparent resin, polyester such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide, polyphenylene sulfide, aramid, polypropylene, polyethylene, polylactic acid, polyvinyl chloride, polycarbonate, polymethyl methacrylate, alicyclic acrylic resin Resin, cycloolefin resin, triacetyl cellulose, epoxy resin, phenol resin, alkyd resin, petroleum resin, vinyl resin, olefin resin, synthetic rubber, polyamide resin, acrylic resin, styrene resin, melamine resin, urethane resin, amino resin, Fluorine resin, vinylidene fluoride resin, vinyl chloride resin, ABS resin, silicone resin, nitrocellulose, rosin modified phenolic resin, rosin modified polyamide resin, natural rubber, zera Down, rosin, mention may be made of shellac, polysaccharides, Gilsonite and the like. Usual soda glass can be used as the glass. These plural substrates can also be used in combination. In addition, carbon black or carbon nanotubes (c) may be included to such an extent that the carbon nanotube layer (b) can be visually recognized.

  As a method of forming the clear layer (e), an optimum method may be selected according to the substance to be formed, and a dry method such as vacuum evaporation, EB evaporation, sputter evaporation, casting, spin coating, dip coating, bar coating, spray General methods such as blade coating, slit die coating, gravure coating, reverse coating, screen printing, mold coating, printing transfer, and wet coating methods such as inkjet can be mentioned. Moreover, you may laminate the clear layer (e) what was formed into a film.

  The film thickness of the clear layer (e) is preferably in the range of 5 to 40 μm, preferably 25 to 35 μm. If it is such a range in particular, a laminate excellent in jet blackness can be obtained.

  EXAMPLES The present invention will be more specifically described below by way of Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded. In the examples, unless otherwise specified, "part" means "part by mass", and "%" means "% by mass" respectively. Moreover, "carbon nanotube" may be abbreviated as "CNT" and "carbon black" may be abbreviated as "CB".

<Method of measuring physical properties>
Physical properties of the laminate used in each of the following Examples and Comparative Examples were measured by the following methods.

<Film thickness>
The film thickness of the carbon nanotube-containing layer and the clear layer in the laminate was measured at 3 points using a film thickness meter (manufactured by NIKON, DIGIMICRO MH-15M), and the average value was taken as the film thickness.

<L ^* a ^* b ^* >
From the surface direction of the clear layer of the laminate, using the color difference meter (Nippon Denshoku Co., Ltd., SpectroColorMeter SE2000), the lightness (L ^* ) and the chromaticity (a *, L ^* ) in the L ^* a ^* b ^* color system specified by JIS b *) was measured.

<Average reflectance>
Measure the absolute reflection spectrum at a wavelength of 300 to 1500 nm in the range of 5 nm from the surface direction of the clear layer of the laminate using an ultraviolet visible near infrared spectrophotometer (manufactured by Hitachi, Ltd., UV-3500, using an integrating sphere), The weighted average value of each reflectance of wavelength 380nm-780nm is calculated | required, and this is made into average reflectance.

Fiber diameter of carbon nanotubes
The obtained carbon nanotubes were observed by a scanning transmission electron microscope (JEM-6700M manufactured by JEOL Ltd.). In the observation photograph, arbitrary 100 carbon nanotubes were selected, the outer diameter of each was measured, and the fiber diameter (nm) of the carbon nanotubes was calculated by calculating the number average value.

<Average particle size of carbon black>
The carbon black was observed by a scanning transmission electron microscope (JEM-6700M manufactured by Nippon Denshi Co., Ltd.). In the observation photograph, 100 arbitrary carbon blacks were selected, the outer diameter of each was measured, and the average particle diameter (nm) of carbon black was calculated by calculating the number average value.

<Example of catalyst for carbon nanotube synthesis and production of carbon nanotubes>
The catalyst for carbon nanotube synthesis and the carbon nanotube used in each of the following Examples and Comparative Examples were produced by the following method.

<Preparation of Catalyst (A) for Carbon Nanotube Synthesis>
200 g of cobalt acetate tetrahydrate and 172 g of magnesium acetate tetrahydrate as a supporting component were weighed in a beaker and stirred until uniform. After transferring to a heat resistant container and drying for 30 minutes at a temperature of 190 ± 5 ° C. using an electric oven to evaporate water, it was ground in a mortar to obtain a precursor of a catalyst for carbon nanotube synthesis (A) . 100 g of the obtained precursor of the catalyst for carbon nanotube synthesis (A) is weighed in a heat resistant container, calcined in an atmosphere of 500 ° C. ± 5 ° C. in air for 30 minutes in a muffle furnace, and then crushed in a mortar I got (A).

<Preparation of catalyst (B) for carbon nanotube synthesis>
74 g of cobalt hydroxide and 172 g of magnesium acetate tetrahydrate as a supporting component were weighed in a beaker and stirred until uniform. It was transferred to a heat resistant container and dried for 30 minutes at a temperature of 190 ± 5 ° C. using an electric oven to evaporate water, and then ground in a mortar to obtain a precursor of a catalyst (B) for carbon nanotube synthesis . 100 g of the obtained precursor of the catalyst for carbon nanotube synthesis (B) is weighed in a heat resistant container, calcined in an atmosphere of 500 ° C. ± 5 ° C. in air for 30 minutes in a muffle furnace, and then pulverized in a mortar I got (B).

<Production of Carbon Nanotube (A1)>
In a central portion of a horizontal reaction tube capable of being pressurized and heated by an external heater and having an inner volume of 10 liters, a quartz glass heat-resistant dish, in which 1.0 g of a catalyst for carbon nanotube synthesis (A) was dispersed, was installed. The exhaust was performed while injecting argon gas, the air in the reaction tube was replaced with argon gas, and the atmosphere in the horizontal reaction tube was adjusted to an oxygen concentration of 1% by volume or less. Subsequently, it heated with an external heater and heated until the center temperature in a horizontal reaction tube became 700 degreeC. After reaching 700 ° C., hydrogen gas was introduced into the reaction tube for 1 minute at a flow rate of 0.1 liter per minute to activate the catalyst. Thereafter, ethylene gas as a carbon source was introduced into the reaction tube at a flow rate of 1 liter per minute, and contact reaction was performed for 1 hour. After completion of the reaction, the gas in the reaction tube was replaced with argon gas, the temperature in the reaction tube was cooled to 100 ° C. or less, and the obtained carbon nanotubes were collected. The obtained carbon nanotubes were crushed and filtered through a 80 mesh wire mesh.

<Production of Carbon Nanotube (A2)>
In a central portion of a horizontal reaction tube capable of being pressurized and heated by an external heater and having an inner volume of 10 liters, a quartz glass heat-resistant dish, in which 1.0 g of a catalyst for carbon nanotube synthesis (A) was dispersed, was installed. The exhaust was performed while injecting argon gas, the air in the reaction tube was replaced with argon gas, and the atmosphere in the horizontal reaction tube was adjusted to an oxygen concentration of 1% by volume or less. Subsequently, it heated with an external heater and heated until the center temperature in a horizontal reaction tube became 700 degreeC. After reaching 700 ° C., hydrogen gas was introduced into the reaction tube for 1 minute at a flow rate of 0.1 liter per minute to activate the catalyst. Thereafter, ethylene gas as a carbon source was introduced into the reaction tube at a flow rate of 1 liter per minute, and contact reaction was performed for 2 hours. After completion of the reaction, the gas in the reaction tube was replaced with argon gas, the temperature in the reaction tube was cooled to 100 ° C. or less, and the obtained carbon nanotubes were collected. The obtained carbon nanotubes were crushed and filtered through a 80 mesh wire mesh.

<Production of Carbon Nanotube (B1)>
In a central portion of a horizontal reaction tube capable of being pressurized and heated by an external heater and having an inner volume of 10 liters, a quartz glass heat-resistant dish in which 1.0 g of a catalyst (B) for carbon nanotube synthesis was dispersed was installed. The exhaust was performed while injecting argon gas, the air in the reaction tube was replaced with argon gas, and the atmosphere in the horizontal reaction tube was adjusted to an oxygen concentration of 1% by volume or less. Subsequently, it heated with an external heater and heated until the center temperature in a horizontal reaction tube became 700 degreeC. After reaching 700 ° C., hydrogen gas was introduced into the reaction tube for 1 minute at a flow rate of 0.1 liter per minute to activate the catalyst. Thereafter, ethylene gas as a carbon source was introduced into the reaction tube at a flow rate of 1 liter per minute, and contact reaction was performed for 1 hour. After completion of the reaction, the gas in the reaction tube was replaced with argon gas, the temperature in the reaction tube was cooled to 100 ° C. or less, and the obtained carbon nanotubes were collected. The obtained carbon nanotubes were crushed and filtered through a 80 mesh wire mesh.

<Production of Carbon Nanotube (B2)>
In a central portion of a horizontal reaction tube capable of being pressurized and heated by an external heater and having an inner volume of 10 liters, a quartz glass heat-resistant dish in which 1.0 g of a catalyst (B) for carbon nanotube synthesis was dispersed was installed. The exhaust was performed while injecting argon gas, the air in the reaction tube was replaced with argon gas, and the atmosphere in the horizontal reaction tube was adjusted to an oxygen concentration of 1% by volume or less. Subsequently, it heated with an external heater and heated until the center temperature in a horizontal reaction tube became 700 degreeC. After reaching 700 ° C., hydrogen gas was introduced into the reaction tube for 1 minute at a flow rate of 0.1 liter per minute to activate the catalyst. Thereafter, ethylene gas as a carbon source was introduced into the reaction tube at a flow rate of 1 liter per minute, and contact reaction was performed for 2 hours. After completion of the reaction, the gas in the reaction tube was replaced with argon gas, the temperature in the reaction tube was cooled to 100 ° C. or less, and the obtained carbon nanotubes were collected. The obtained carbon nanotubes were crushed and filtered through a 80 mesh wire mesh.

<Production of CNT-Containing Resin Composition>
First, prior to Examples, a method for producing a CNT-containing resin composition is shown below.

<Production of CNT-Containing Resin Composition 1>
0.5 parts of a carbon nanotube (A1) and 99.5 parts of a PET resin (ethylene glycol-terephthalic acid copolymer, MA-2101, manufactured by Unitika) are put into a super mixer (manufactured by Kawata) and brought to 25 ° C. The mixture was stirred for 3 minutes to obtain a mixture. Then, the mixture was introduced into a twin-screw extruder (manufactured by Nippon Placon Co., Ltd.), extruded at 260 ° C., and cut with a pelletizer to obtain a CNT-containing resin composition 1.

<Production of CNT-Containing Resin Composition 2 to 14>
The CNT-containing resin compositions 2 to 14 were respectively prepared by the same method as the method for producing the CNT-containing resin composition 1 except that the types of resins, types of carbon nanotubes, and addition amount of carbon nanotubes listed in Table 1 were changed. Obtained.

<Preparation of Carbon Black-Containing Resin Composition 1>
5 parts of carbon black (furness black powder, Nitrone # 10, average particle diameter 40 nm, manufactured by Nippon Steel Carbon Co., Ltd.), and 95 parts of a PET resin (ethylene glycol-terephthalic acid copolymer, MA-2101, manufactured by Unitika) The mixture was charged into a super mixer (manufactured by Kawata Co., Ltd.) and stirred at 25 ° C. for 3 minutes to obtain a mixture. Subsequently, the mixture was charged into a twin-screw extruder (manufactured by Nippon Placon Co., Ltd.), extruded at 260 ° C., and cut with a pelletizer to obtain a carbon black-containing resin composition 1.

<Preparation of clear paint>
The clear paint used to form the clear layer is an organic solvent (a mixed solution of toluene / xylene / ethyl acetate / butyl acetate = 70 parts / 15 parts / 10 parts / 5 parts) in a round bottom flask and used for baking a melamine An acrylic resin (manufactured by DIC Corporation, ACRYDIC A405) was added and prepared by stirring for 1 hour.

Example 1
<Preparation of CNT-Containing Layer 1>
The CNT-containing resin composition 1 was extrusion molded at 280 ° C. with a T-die extruder to form a CNT-containing film having a thickness of 100 μm, which was used as the CNT-containing layer 1.
<Creating a Laminate 1>
The clear coating is applied using a bar coater so that the film thickness after drying is 10 μm, using the CNT-containing layer 1 as a base material, and then dried in an electric oven at 150 ± 5 ° C. for 20 minutes to obtain a clear layer The laminated body 1 was produced by forming. L ^* a ^* b ^* and average reflectance were measured about the obtained laminated body.

(Examples 2 to 19)
The same as Example 1, except that the type or thickness of the CNT-containing resin composition listed in Table 2 and the CNT-containing layer and the clear layer are changed instead of the CNT-containing resin composition 1 used in Example 1. Laminates 2 to 12 were produced by the method. L * a * b * and an average reflectance were measured about the obtained laminated body.
However, Examples 2 and 3 are reference examples.

The preparation conditions and evaluation result of the laminated body produced in Examples 1-19 in Table 2 are shown.
Evaluation criteria for jet blackness were as follows.
場合 L ^* less than 24 and b ^* less than 0.3 (very good)
○ If L ^* satisfies both 24 and 26 and b ^* is 0.3 or less (good)
× L ^* exceeds 26 or b ^* exceeds 0.3 or less (defect)

(Comparative example 1)
<Preparation of carbon black-containing layer>
The carbon black-containing resin composition 1 was extrusion molded at 280 ° C. with a T-die extruder to form a carbon black-containing film having a thickness of 100 μm, which was used as a carbon black-containing layer. Then, a laminate 20 was produced in the same manner as the laminate 1 except that a carbon black-containing layer was used instead of the CNT-containing layer 1, and L ^* a ^* b ^* was measured.

(Comparative example 2)
The L ^* a ^* b ^* and the average reflectance were measured for only the CNT-containing layer 1 in which the clear layer was not formed in Example 1.

  Table 3 shows preparation conditions and evaluation results of the laminates manufactured in Comparative Examples 1 and 2.

(Example 21)
<Creating a CNT-Containing Layer 21>
The CNT-containing resin composition 1 is injection molded using an injection molding machine (type IS-100F manufactured by Toshiba Machine Co., Ltd.) to form a CNT-containing plate 100 mm long × 100 mm wide × 3 mm thick, and a CNT-containing layer 21 And

<Creating a Laminate 21>
The clear coating is applied using a bar coater such that the film thickness after drying is 10 μm, using the CNT-containing layer 21 as a base material, and then dried in an electric oven at 150 ± 5 ° C. for 20 minutes to obtain a clear layer The laminated body 21 was produced by forming. L ^* a ^* b ^* and average reflectance were measured about the obtained laminated body.

(Examples 22 to 28)
The same as Example 21, except that the type or film thickness of the CNT-containing resin composition listed in Table 4 and the CNT-containing layer and the clear layer is changed instead of the CNT-containing resin composition 1 used in Example 21. Laminates 22 to 28 were produced by the method. L ^* a ^* b ^* and average reflectance were measured about the obtained laminated body.

(Comparative example 3)
<Preparation of carbon black-containing layer>
The carbon black-containing resin composition 1 is injection molded using an injection molding machine (type IS-100F manufactured by Toshiba Machine Co., Ltd.) to prepare a CB-containing plate of 100 mm long × 100 mm wide × 3 mm thick, containing carbon black It was a layer. Subsequently, a laminate 29 was produced in the same manner as the laminate 21 except that a carbon black-containing layer was used instead of the CNT-containing layer 1, and L ^* a ^* b ^* was measured.

(Comparative example 4)
The L ^* a ^* b ^* and the average reflectance were measured for only the CNT-containing layer 21 in which the clear layer was not formed in Example 21.

  Table 5 shows preparation conditions and evaluation results of the laminates manufactured in Comparative Examples 3 and 4.

(Example 31)
<Preparation of CNT-Containing Layer 31>
The CNT-containing resin composition 10 was subjected to inflation molding using a small-sized inflation molding machine (manufactured by Thermo Plastics Industry Co., Ltd.) to form a 50 μm-thick tubular inflation-formed CNT film, which was used as the CNT-containing layer 31. .

<Creating a Laminate 31>
The clear coating is applied using a bar coater such that the film thickness after drying is 10 μm using the CNT-containing layer 31 as a base material, and then dried in an electric oven at 120 ± 5 ° C. for 20 minutes to obtain a clear layer The laminated body 31 was produced by forming. L ^* a ^* b ^* and average reflectance were measured about the obtained laminated body.

(Examples 32-36)
Example instead of the CNT-containing resin composition 10 used in Example 31, except changing the type or film thickness of the CNT-containing resin composition and CNT-containing layer listed in Table 6, and the film thickness of the clear layer Laminates 32 to 36 were produced in the same manner as 31. L ^* a ^* b ^* and average reflectance were measured about the obtained laminated body.

(Comparative example 5)
<Preparation of carbon black-containing layer>
The carbon black-containing resin composition 1 was subjected to inflation molding using a small inflation molding machine (manufactured by Thermo Plastics Industry Co., Ltd.) to prepare a 50 μm-thick cylindrical inflation molded CB film. Subsequently, a laminate 37 was produced in the same manner as the laminate 31 except that a carbon black-containing layer was used instead of the CNT-containing layer 31, and L ^* a ^* b ^* was measured.

(Comparative example 6)
The L ^* a ^* b ^* and the average reflectance were measured for only the CNT-containing layer 31 in which the clear layer was not formed in Example 31.

  Table 7 shows preparation conditions and evaluation results of the laminates manufactured in Comparative Examples 5-6.

  From the above results, when the laminate containing the carbon nanotube of the present invention and a resin is used, a laminate having high jet-blackness can be obtained as compared with the laminate using the carbon black used in the comparative example or the clear layer. It became clear.

Claims (7)

A laminate comprising a carbon nanotube-containing layer comprising carbon nanotubes and a resin, and a clear layer,
The fiber diameter of the carbon nanotube is 8 to 25 nm,
The amount of carbon nanotubes in the carbon nanotube-containing layer is 0.5 to 10% by mass,
L * of the laminate measured from the surface direction of the clear layer is 26 or less and b * is -10 or more and 0.3 or less, the carbon nanotube-containing layer is formed by a method other than coating, and the clear layer is a transparent resin Or a laminate characterized in that it is glass.
(However, L * and b * represent values in the L * a * b * color system specified in JIS Z8729.)   The laminate according to claim 1, wherein the method other than coating is any method of extrusion molding, injection molding, blow molding, compression molding, transfer molding, inflation molding, or calendar molding. The laminated body in any one of Claim 1 or 2 whose film thickness of a carbon nanotube containing layer is 50 micrometers-5 mm. The film thickness of the clear layer is the laminate of claim 1 to 3, wherein any one is 5Myuemu～40myuemu. The average reflectance in wavelength 380-780 nm of the laminated body measured from the surface direction of a clear layer is 10% or less, The laminated body in any one of Claims 1-4 . A method for producing a laminate having a carbon nanotube-containing layer comprising a carbon nanotube and a resin, and a clear layer,
The fiber diameter of the carbon nanotube is 8 to 25 nm,
The amount of carbon nanotubes in the carbon nanotube-containing layer is 0.5 to 10% by mass,
L * of the laminate measured from the surface direction of the clear layer is 26 or less and b * is -10 or more and 0.3 or less, the clear layer is a transparent resin or glass, and the carbon nanotube-containing layer is a method other than coating A method of producing a laminate, characterized in that it is formed.
(However, L *, a * and b * represent values in the L * a * b * color system specified in JIS Z8729.) The method for producing a laminate according to claim 6 , wherein the method other than coating is any method of extrusion molding, injection molding, blow molding, compression molding, transfer molding, inflation molding, or calendar molding.