Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J125/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Adhesives based on derivatives of such polymers
  • C09J125/02—Homopolymers or copolymers of hydrocarbons
  • C09J125/04—Homopolymers or copolymers of styrene
  • C09J125/08—Copolymers of styrene
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J179/00—Adhesives based on macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen, with or without oxygen, or carbon only, not provided for in groups C09J161/00 - C09J177/00
  • C09J179/04—Polycondensates having nitrogen-containing heterocyclic rings in the main chain; Polyhydrazides; Polyamide acids or similar polyimide precursors
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/20—Adhesives in the form of films or foils characterised by their carriers
  • C09J7/22—Plastics; Metallised plastics
  • C09J7/25—Plastics; Metallised plastics based on macromolecular compounds obtained otherwise than by reactions involving only carbon-to-carbon unsaturated bonds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/03—Use of materials for the substrate
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/38—Improvement of the adhesion between the insulating substrate and the metal

Definitions

• the present invention relates to adhesive compositions. More particularly, it relates to an adhesive composition that can be used for bonding electronic parts and the like.
• FPCs flexible printed circuit boards
• the dielectric of the constituent elements and low dielectric base films and low dielectric adhesives are being developed.
• low-dielectric adhesives have problems in chemical resistance and heat resistance because the polarity of the base material molecules is low and the crosslink density is also low. From the viewpoint of providing a low-dielectric adhesive layer that adheres even to a low-dielectric base film with poor adhesion and has both chemical resistance and heat resistance, the adhesive described in Patent Document 1 is not satisfactory. However, there was room for improvement.
• the present invention has good electrical properties (dielectric properties) that are compatible with 5G, exhibits good adhesion even to low-dielectric base films with poor adhesion, and has heat resistance and chemical resistance.
• An object of the present invention is to provide an adhesive composition for forming a low-dielectric adhesive layer that also has solvent properties.
• the adhesive composition contains a styrene-based elastomer containing an amino group and a benzoxazine resin. , found that the above problems can be solved, and completed the present invention.
• the present invention includes the following aspects.
• the adhesive composition according to [1] which contains 30 to 95 parts by mass of the amino group-containing styrene-based elastomer with respect to 100 parts by mass of the adhesive composition.
• a coverlay film with an adhesive layer comprising the laminate according to [10] or [11].
• a copper-clad laminate comprising the laminate according to [10] or [11].
• a printed wiring board comprising the laminate according to [10] or [11].
• a shielding film comprising the laminate according to [10] or [11].
• a printed wiring board with a shielding film comprising the laminate according to [10] or [11].
• the present invention while having good electrical properties (dielectric properties) compatible with 5G, it exhibits good adhesion even to low-dielectric substrate films with poor adhesion, and has heat resistance and chemical resistance (resistance). It is possible to provide an adhesive composition for forming a low dielectric adhesive layer that also has solvent properties.
• the adhesive composition of the present invention a laminate containing an adhesive layer made of the adhesive composition, and an electronic component-related constituent member containing the laminate will be described in detail. is an example as one embodiment of the present invention, and is not limited to these contents.
• the adhesive composition of the present invention contains a styrene-based elastomer and a benzoxazine resin.
• the styrenic elastomer used in the present invention contains a styrenic elastomer containing an amino group.
• the styrene elastomer contained in the adhesive composition contains a modified styrene elastomer.
• the modified styrenic elastomer contains at least a styrenic elastomer containing an amino group.
• the styrene elastomer used in the present invention may contain a modified styrene elastomer other than the amino group-containing styrene elastomer, or may contain an unmodified styrene elastomer other than the modified styrene elastomer. good.
• the adhesive composition of the present invention preferably contains at least two types of styrenic elastomers from the viewpoint of satisfying various properties required for the adhesive composition.
• Styrenic elastomers are copolymers composed mainly of block and random structures of unsaturated hydrocarbons and aromatic vinyl compounds, and hydrogenated products thereof.
• aromatic vinyl compounds examples include styrene, t-butylstyrene, ⁇ -methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-diethyl-p-aminoethylstyrene and vinyltoluene.
• unsaturated hydrocarbons include ethylene, propylene, butadiene, isoprene, isobutene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like.
• the styrene elastomer used in the present invention preferably has a weight average molecular weight of 30,000 or more, more preferably 70,000 or more. If the weight average molecular weight is 30,000 or more, excellent adhesiveness can be exhibited. If the weight-average molecular weight is 70,000 or more, the film-forming property is improved when the polymer is dissolved in a solvent and applied, and thickness unevenness due to pinholes and dripping is less likely to occur. Performance deviation is small, and lack of adhesion and chemical resistance is less likely to occur. In addition, it becomes easy to control the thickness, which is important when manufacturing a printed wiring board.
• a styrene-based elastomer having a weight average molecular weight of 100,000 or more it is preferable to contain a styrene-based elastomer having a weight average molecular weight of 100,000 or more.
• a styrene-based elastomer having a weight-average molecular weight of 100,000 or more is contained, excessive resin flow (resin flow) can be suppressed.
• the styrene elastomer preferably has a weight average molecular weight of 300,000 or less, more preferably 200,000 or less. If the weight average molecular weight is 300,000 or less, the compatibility with the benzoxazine resin is improved, and excellent chemical resistance can be exhibited.
• the weight-average molecular weight is 200,000 or less, it is possible to suppress an increase in viscosity during coating by dissolving in a solvent, and improve leveling properties, thereby forming a film with a smooth surface. As a result, fluctuations in performance on the coated surface are small, insufficient adhesion and chemical resistance are less likely to occur, and thickness control, which is important in the production of printed wiring boards, becomes easier.
• the weight average molecular weight is a value obtained by converting the molecular weight measured by gel permeation chromatography (hereinafter also referred to as "GPC") into polystyrene.
• the styrene elastomer used in the present invention preferably has a styrene ratio of 20 or more, more preferably 30 or more. If the styrene ratio is 20 or more, excellent adhesiveness can be exhibited. If the styrene ratio is 30 or more, the heat resistance of the adhesive composition can be expressed. Moreover, it is preferable to contain a styrene-based elastomer having a styrene ratio of 40 or more. When a styrene-based elastomer having a styrene ratio of 40 or more is contained, the compatibility with the benzoxazine resin is improved, and excellent adhesiveness and chemical resistance can be exhibited.
• the styrene-based elastomer preferably has a styrene ratio of 80 or less, more preferably 60 or less.
• the styrene ratio is 80 or less, the fluidity at the time of heating can be enhanced, so that the surface of the substrate film can be sufficiently followed and excellent adhesive strength can be exhibited. If the styrene ratio is 60 or less, procurement of the styrene-based elastomer is easy.
• the styrene ratio of at least one styrene-based elastomer is preferably 40 or more.
• Types of styrene elastomers include styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-ethylene copolymers, their random copolymers, block copolymers, hydrogenated products thereof, and the like. mentioned.
• a hydrogenated styrene-butadiene block copolymer is preferable.
• the block structure mainly composed of styrene can improve compatibility with benzoxazine resin, and the block structure mainly derived from butadiene imparts high flexibility.
• styrene-based elastomers include styrene-butadiene block copolymers, styrene-ethylenepropylene block copolymers, styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, and styrene-ethylenebutylene.
• styrene block copolymers and styrene-ethylene propylene-styrene block copolymers may be used alone or in combination of two or more.
• the styrene-based elastomer of the present invention includes modified styrene-based elastomers in which substituents have been introduced into the above structures, and unmodified styrene-based elastomers in which no substituents have been introduced.
• the adhesive composition of the present invention contains a modified styrene-based elastomer, it reacts with a benzoxazine resin, a cross-linking agent, etc., which will be described later, and cures, thereby exhibiting excellent adhesiveness and chemical resistance.
• the introduced substituent since the introduced substituent has a strong interaction with metal, the inclusion of the modified styrene-based elastomer improves the adhesive strength between the adhesive composition and the metal substrate.
• Modified styrenic elastomers are copolymers mainly composed of block and random structures of unsaturated hydrocarbons and aromatic vinyl compounds, and hydrogenated products thereof containing carboxy groups, amino groups, epoxy groups, isocyanate groups, acryloyl , a hydroxyl group, a mercapto group, an imide group, an alkoxysilyl group, and the like.
• the adhesive composition of the present invention contains a styrene elastomer containing at least an amino group as the modified styrene elastomer.
• the adhesive composition of the present invention may contain modified styrene-based elastomers other than the amino group-containing styrene-based elastomer as long as the effects of the present invention are not impaired.
• the method of amine-modifying the styrene elastomer is not particularly limited, and a known method can be used.
• a modification method a method of amine-modifying a (hydrogenated) copolymer by using an unsaturated monomer having an amino group as a raw material to be copolymerized, and a styrene-based elastomer containing a carboxy group with two amino groups.
• a method of modifying the amine by reacting the above amine modifier to form an amide structure or an imide structure, and the like.
• styrene-based elastomers containing amino groups include those obtained by introducing amino groups into the aforementioned styrene-based elastomers.
• the total nitrogen content in the amino group-containing styrene elastomer is , preferably 50 to 5000 ppm, more preferably 200 to 3000 ppm. If the total nitrogen content is at least the above lower limit, excellent adhesion can be exhibited. If the total nitrogen content is equal to or less than the above upper limit, the electrical properties are excellent.
• the total nitrogen content in the styrene-based elastomer containing amino groups can be determined according to JIS-K2609 using a trace nitrogen analyzer ND-100 (manufactured by Mitsubishi Chemical Corporation).
• the content of the styrene-based elastomer containing an amino group in the adhesive composition is preferably contained in an amount of 30 to 95 parts by mass, more preferably 30 to 80 parts by mass.
• a styrene-based elastomer containing a carboxy group is effective as a component that imparts electrical properties in addition to adhesiveness and flexibility of a cured product.
• Carboxy group-containing styrenic elastomers are copolymers mainly composed of block and random structures of unsaturated hydrocarbons and aromatic vinyl compounds, and hydrogenated products thereof modified with unsaturated carboxylic acids. .
• the types of the aromatic vinyl compound and the unsaturated hydrocarbon and specific examples of the styrene-based elastomer are as described in the section ⁇ Styrene-based elastomer> above.
• Modification of a styrene-based elastomer containing a carboxy group can be carried out, for example, by copolymerizing an unsaturated carboxylic acid during polymerization of the styrene-based elastomer. It can also be carried out by heating and kneading a styrene-based elastomer and an unsaturated carboxylic acid in the presence of an organic peroxide.
• unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, maleic anhydride, and itaconic anhydride.
• the amount of modification with unsaturated carboxylic acid is preferably 0.1 to 10% by mass.
• the acid value of the styrene-based elastomer containing carboxy groups is preferably 0.1 to 25 mgKOH/g, more preferably 0.5 to 23 mgKOH/g.
• the acid value is 0.1 mgKOH/g or more, the adhesive composition is sufficiently cured, and good adhesiveness and heat resistance can be obtained.
• the acid value is 30 mgKOH/g or less, the cohesive force of the adhesive composition is suppressed, resulting in excellent adhesiveness and excellent electrical properties.
• the adhesive composition of the present invention may contain an unmodified styrene elastomer in addition to the modified styrene elastomer. Only one type of unmodified styrene elastomer may be used, or two or more types may be contained.
• Unmodified styrene elastomers are copolymers mainly composed of block and random structures of unsaturated hydrocarbons and aromatic vinyl compounds, and hydrogenated products thereof. There are few highly polar bonding groups in the molecule, and good electrical properties (dielectric properties) can be imparted to the composition. Another advantage is that the molecular weight can be easily controlled and the properties of the adhesive composition can be stably produced compared to other types of elastomers.
• the types of the aromatic vinyl compound and the unsaturated hydrocarbon and specific examples of the styrene-based elastomer are as described in the section ⁇ Styrene-based elastomer> above.
• the content of the unmodified styrene-based elastomer is preferably 35 to 100 parts by mass with respect to 100 parts by mass of the styrene-based elastomer containing amino groups. If the content of the unmodified styrene elastomer relative to 100 parts by mass of the styrene elastomer containing an amino group is within the above range, the effect of adjusting the elastic modulus and fluidity of the adhesive composition by blending the unmodified styrene elastomer. is likely to occur.
• the weight average molecular weight (Mw) of the unmodified styrene elastomer is preferably 100,000 or more, more preferably 100,000 to 200,000. Within the above range, it is possible to achieve both fluidity control and adhesion.
• the unmodified styrene elastomer used in the present invention preferably has a styrene ratio of 40-80.
• a styrene-based elastomer having a styrene ratio of 40 or more is contained, the compatibility with the benzoxazine resin is improved, and excellent adhesiveness and chemical resistance can be exhibited.
• the benzoxazine resin increases the cross-linking density of the adhesive composition, thereby making it possible to exhibit high adhesion to adherends and the chemical resistance and heat resistance of the cured adhesive.
• the benzoxazine resin undergoes a self-polymerization reaction to form a crosslinked structure.
• the benzoxazine preferably has a structure containing two or more oxazine skeletons in the molecule from the viewpoint of increasing the content of the highly adhesive styrene-based elastomer and improving the crosslink density.
• Benzoxazine resins include, for example, 6,6-(1-methylethylidene)bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine), 6,6-(1-methylethylidene) Examples thereof include bis(3,4-dihydro-3-methyl-2H-1,3-benzoxazine) and the like, and two or more of them may be combined.
• a phenyl group, a methyl group, a cyclohexyl group, or the like may be bonded to the nitrogen of the oxazine ring.
• Specific examples of benzoxazine resins include "Benzoxazine Fa", "Benzoxazine Pd" and "Benzoxazine ALP-d” manufactured by Shikoku Kasei Co., Ltd., and the like.
• the melting point or softening point of the benzoxazine resin gives fluidity to the adhesive composition at the temperature of heat lamination or heat press, allowing it to follow the surface of the substrate film or metal substrate sufficiently, resulting in excellent adhesion and curing. It is preferably less than 120° C. from the viewpoint of exhibiting chemical resistance at times.
• the melting point or softening point of the benzoxazine resin is preferably 40° C. or higher from the viewpoint of increasing the elastic modulus of the adhesive composition at room temperature and improving the adhesion.
• the content of the benzoxazine resin in the adhesive composition is preferably 5 parts by mass or more with respect to 100 parts by mass of the adhesive composition from the viewpoint of expressing chemical resistance and heat resistance.
• the content of the benzoxazine resin is preferably 70 parts by mass or less, more preferably 50 parts by mass or less. If the content of the benzoxazine resin is 5 parts by mass or more, excellent chemical resistance to the substrate film can be exhibited. If the content of the benzoxazine resin is 70 parts by mass or less, excellent dielectric properties can be exhibited.
• the adhesive composition of the present invention may contain, in addition to the styrene elastomer, a resin component other than the styrene elastomer and other components.
• the adhesive composition of the present invention may contain other resin components in addition to the styrene-based elastomer and benzoxazine resin.
• the adhesive composition according to the present invention can contain, for example, thermoplastic resins other than the styrene-based elastomer to such an extent that the functions of the adhesive composition are not affected.
• thermoplastic resins include phenoxy resins, polyamide resins, polyester resins, polycarbonate resins, polyphenylene oxide resins, polyurethane resins, polyacetal resins, polyethylene resins, polypropylene resins, polybutadiene resins, and polyvinyl resins. is mentioned. These thermoplastic resins may be used alone or in combination of two or more.
• the resin composition used in the present invention may contain other components in addition to the resin components such as the styrene-based elastomer, benzoxazine resin, and other resin components described above.
• Other components include, for example, a cross-linking agent that reacts with the styrene-based elastomer and benzoxazine resin to form a cross-linked structure.
• a reaction accelerator that accelerates the reaction between the styrene-based elastomer, benzoxazine resin and the cross-linking agent may be included.
• other components include, for example, fillers, tackifiers, flame retardants, heat anti-aging agents, leveling agents, antifoaming agents, inorganic fillers and pigments. These can be contained to the extent that they do not affect the functions of the adhesive composition.
• cross-linking agent examples include epoxy resins, isocyanate resins, phenol resins, cyanate resins, polyamides, polyurethanes, organic peroxides, silane coupling agents, and the like. Only one type of cross-linking agent may be used, or two or more types may be contained.
• the adhesive composition of the present invention preferably contains a filler.
• a filler for example, an inorganic filler is preferable from the viewpoint of heat resistance and mechanical property control of the adhesive composition, and as the inorganic filler, a silicon-based inorganic filler and boron nitride are preferable from the viewpoint of electrical properties. preferable.
• the silicon-based inorganic filler for example, mica and talc are preferable because they can control the mechanical properties of the adhesive composition even in a small amount and have excellent electrical properties.
• an organic filler is preferable from the viewpoint of dispersibility and brittleness
• a styrene-based spherical filler is preferable from the viewpoint of electrical properties
• a styrene-based hollow filler is preferable. more preferred. These may be used alone or in combination of two or more.
• the content of the filler contained in the adhesive composition of the present invention is preferably 0.5 to 25 parts by volume with respect to 100 parts by volume of the resin composition, and 1 to 15 parts by volume with respect to 100 parts by volume of the resin composition. is more preferable.
• the shape of the filler is not particularly limited and can be appropriately selected depending on the purpose.
• the inorganic filler may be a spherical inorganic filler or a non-spherical inorganic filler, but a non-spherical inorganic filler is preferable from the viewpoint of coefficient of thermal expansion (CTE) and film strength.
• the shape of the non-spherical inorganic filler may be any three-dimensional shape other than a spherical shape (substantially spherical shape), and examples thereof include plate-like, scale-like, columnar, chain-like, and fibrous shapes. Among them, from the viewpoint of coefficient of thermal expansion (CTE) and film strength, plate-like and scale-like inorganic fillers are preferable, and plate-like inorganic fillers are more preferable.
• tackifiers examples include coumarone-indene resin, terpene resin, terpene-phenol resin, rosin resin, pt-butylphenol-acetylene resin, phenol-formaldehyde resin, xylene-formaldehyde resin, petroleum-based hydrocarbon resin, Examples include hydrogenated hydrocarbon resins and turpentine resins. These tackifiers may be used alone or in combination of two or more.
• the above flame retardant may be either an organic flame retardant or an inorganic flame retardant.
• organic flame retardants include melamine phosphate, melamine polyphosphate, guanidine phosphate, guanidine polyphosphate, ammonium phosphate, ammonium polyphosphate, amide ammonium phosphate, amide ammonium polyphosphate, carbamate phosphate, and carbamate polyphosphate.
• triazine compounds such as melamine,
• Inorganic flame retardants include metal hydroxides such as aluminum hydroxide, magnesium hydroxide, zirconium hydroxide, barium hydroxide, and calcium hydroxide; tin oxide, aluminum oxide, magnesium oxide, zirconium oxide, zinc oxide, Metal oxides such as molybdenum oxide and nickel oxide; zinc carbonate, magnesium carbonate, barium carbonate, zinc borate, hydrated glass and the like. These flame retardants can be used in combination of two or more.
• heat antiaging agent examples include 2,6-di-tert-butyl-4-methylphenol, n-octadecyl-3-(3′,5′-di-tert-butyl-4′-hydroxyphenyl)propione.
• examples of the inorganic filler include powders made of titanium oxide, aluminum oxide, zinc oxide, carbon black, silica, copper, silver, and the like. These may be used alone or in combination of two or more.
• the adhesive layer according to the present invention is formed using the adhesive composition of the present invention.
• the adhesive composition that forms the adhesive layer can be cured.
• the curing method is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include heat curing.
• the thickness of the adhesive layer is not particularly limited and can be appropriately selected depending on the intended purpose. Also, it is preferably 100 ⁇ m or less, more preferably 50 ⁇ m or less, and even more preferably 30 ⁇ m or less. If the thickness of the adhesive layer is 3 ⁇ m or more, sufficient adhesive strength can be exhibited, and if it is 5 ⁇ m or more, steps such as the pattern of the printed wiring board can be followed. If the thickness of the adhesive layer is 50 ⁇ m or less, the laminate can be made thinner, and if it is 30 ⁇ m or less, the resin flow can be accurately controlled.
• An adhesive layer can be produced by forming a film from the adhesive composition.
• the adhesive composition can be produced by mixing the styrene-based elastomer and the benzoxazine resin described above.
• the mixing method is not particularly limited as long as the adhesive composition becomes uniform.
• a solvent is also usually used. Examples of solvents include alcohols such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, isobutyl alcohol, n-butyl alcohol, benzyl alcohol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, and diacetone alcohol.
• Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclohexanone, and isophorone; Aromatic hydrocarbons such as toluene, xylene, ethylbenzene, mesitylene, and anisole; Methyl acetate, ethyl acetate, butyl acetate, ethylene glycol monomethyl esters such as ether acetate and 3-methoxybutyl acetate; and aliphatic hydrocarbons such as hexane, heptane, cyclohexane and methylcyclohexane.
• solvents may be used alone or in combination of two or more.
• the adhesive composition is a solvent-containing solution or dispersion (resin varnish)
• coating on the substrate film and formation of the adhesive layer can be performed smoothly, and an adhesive layer having a desired thickness can be formed. can be obtained easily.
• the adhesive composition contains a solvent, the solid content concentration is preferably in the range of 3 to 80% by mass, more preferably 10 to 50% by mass, from the viewpoint of workability including formation of the adhesive layer.
• a resin varnish containing the adhesive composition and a solvent is applied to the surface of a substrate film to form a resin varnish layer, and then the resin varnish is applied to the surface of the substrate film.
• a B-staged adhesive layer can be formed by removing the solvent from the layer.
• the adhesive layer being in a B-stage state means that the adhesive composition is in an uncured state or a semi-cured state in which a part of the adhesive composition has begun to cure, and the curing of the adhesive composition further progresses by heating or the like. It means the state to do.
• the method for applying the resin varnish on the substrate film is not particularly limited and can be appropriately selected according to the purpose.
• a blade coating method, a doctor roll method, a doctor blade method, a curtain coating method, a slit coating method, a screen printing method, an inkjet method, a dispensing method, and the like can be mentioned.
• the B-stage adhesive layer can be further subjected to heating or the like to form a cured adhesive layer.
• the dielectric constant ( ⁇ r) of the adhesive layer obtained by curing the adhesive composition of the present invention at a frequency of 28 GHz is preferably 3.5 or less, more preferably 2.7 or less.
• the dielectric loss tangent (tan ⁇ ) of the adhesive layer at a frequency of 28 GHz is preferably 0.005 or less, more preferably 0.0025 or less, and even more preferably 0.0015 or less. If the dielectric constant is 3.5 or less and the dielectric loss tangent is 0.005 or less, it can also be used for high-frequency FPC-related products that require strict electrical characteristics.
• the dielectric constant is 2.7 or less and the dielectric loss tangent is 0.0025 or less, it is possible to satisfy the electrical characteristics expected for the components of 5G compatible high-frequency FPC related products, LCP ( Liquid crystal polymer) has the same electrical characteristics, and can be suitably used for 5G high-frequency FPC-related products that have strict electrical characteristics requirements.
• the dielectric loss tangent is 0.0015 or less, it can be suitably used for high-frequency FPC-related products utilizing millimeter waves.
• the laminate of the present invention comprises a base film and the adhesive layer on at least one surface of the base film.
• the base film used in the present invention can be selected according to the use of the laminate.
• the laminate when the laminate is used as a cover lay film or a copper clad laminate (CCL), polyimide film, polyether ether ketone film, polyphenylene sulfide film, aramid film, polyethylene naphthalate film, liquid crystal polymer film, and the like can be used.
• polyimide film, polyetheretherketone (PEEK) film, polyethylene naphthalate film, and liquid crystal polymer film are preferred from the viewpoint of adhesion and electrical properties.
• the storage elastic modulus of the base film at 200° C. is 1 ⁇ 10 8 or more. Resin flow is accompanied by deformation of the edges of the base film, and the larger the deformation, the greater the resin flow.
• the base film when used as a bonding sheet, the base film must be a release film, and examples thereof include polyethylene terephthalate film, polyethylene film, polypropylene film, silicone release treated paper, and polyolefin resin. Coated paper, TPX (polymethylpentene) film, fluorine-based resin film, and the like.
• the base film When the laminate of the present invention is used as a shielding film, the base film must be a film having electromagnetic wave shielding ability, and examples thereof include a laminate of a protective insulating layer and a metal foil.
• coverlay film A preferred embodiment of the laminate according to the present invention is a coverlay film.
• a laminate having an adhesive layer called a "coverlay film” is usually used to protect the wiring portion.
• This coverlay film comprises an insulating resin layer and an adhesive layer formed on its surface.
• a coverlay film is a laminate in which the adhesive layer is formed on at least one surface of the base film, and it is generally difficult to separate the base film and the adhesive layer.
• the thickness of the base film included in the coverlay film is preferably 5 to 100 ⁇ m, more preferably 5 to 50 ⁇ m, even more preferably 5 to 30 ⁇ m. If the thickness of the base film is equal to or less than the above upper limit, the thickness of the coverlay film can be reduced.
• the printed wiring board can be easily designed and handled well.
• a method for producing a coverlay film for example, a resin varnish containing the adhesive composition and a solvent is applied to the surface of the base film to form a resin varnish layer, and then the solvent is removed from the resin varnish layer. is removed, a coverlay film having a B-stage adhesive layer formed thereon can be produced.
• the drying temperature for removing the solvent is preferably 40 to 250°C, more preferably 70 to 170°C. Drying is performed by passing the laminate coated with the adhesive composition through a furnace in which hot air drying, far-infrared heating, high-frequency induction heating, or the like is performed.
• a release film may be laminated on the surface of the adhesive layer for storage or the like.
• the releasable film publicly known films such as polyethylene terephthalate film, polyethylene film, polypropylene film, silicone release treated paper, polyolefin resin coated paper, TPX film, and fluororesin film are used. Since the coverlay film according to the present invention uses the low-dielectric adhesive composition of the present invention, it is possible for high-speed transmission of electronic devices, and furthermore, it has excellent adhesive stability with electronic devices. Become.
• a preferred embodiment of the laminate according to the present invention is a bonding sheet.
• the bonding sheet is obtained by forming the adhesive layer on the surface of a release film (base film).
• the bonding sheet may be in a mode in which an adhesive layer is provided between two release films.
• the release film is peeled off before use.
• the releasable film the same one as described in the above section (coverlay film) can be used.
• the thickness of the base film included in the bonding sheet is preferably 5 to 100 ⁇ m, more preferably 25 to 75 ⁇ m, even more preferably 38 to 50 ⁇ m. If the thickness of the base film is within the above range, the bonding sheet can be easily manufactured and handled well.
• a method for producing a bonding sheet for example, there is a method of applying a resin varnish containing the adhesive composition and a solvent to the surface of a release film and drying in the same manner as in the case of the coverlay film. Since the bonding sheet according to the present invention uses the low-dielectric adhesive composition of the present invention, it is capable of high-speed transmission of electronic devices, and has excellent adhesion stability with electronic devices. .
• a preferred embodiment of the laminate according to the present invention is a copper-clad laminate obtained by bonding a copper foil to the adhesive layer in the laminate according to the present invention.
• a copper-clad laminate is obtained by laminating copper foil using the above laminate, and is composed of, for example, a substrate film, an adhesive layer and copper foil in this order.
• the adhesive layer and the copper foil may be formed on both sides of the base film.
• the adhesive composition used in the present invention also has excellent adhesion to articles containing copper. Since the copper-clad laminate according to the present invention uses the low-dielectric adhesive composition of the present invention, it enables high-speed transmission of electronic devices and has excellent adhesion stability.
• the adhesive layer and copper foil of the laminate are brought into surface contact, thermal lamination is performed at 80° C. to 200° C., and the adhesive layer is cured by after-curing.
• the after-curing conditions can be, for example, 100° C. to 200° C. for 30 minutes to 4 hours in an inert gas atmosphere.
• the said copper foil is not specifically limited, Electrolytic copper foil, a rolled copper foil, etc. can be used.
• a preferred embodiment of the laminate according to the present invention is a printed wiring board obtained by laminating copper wiring to the adhesive layer in the laminate according to the present invention.
• a printed wiring board is obtained by forming an electronic circuit on the copper-clad laminate.
• a printed wiring board is formed by laminating a substrate film and copper wiring using the laminate, and is composed of a substrate film, an adhesive layer, and copper wiring in this order.
• the adhesive layer and the copper wiring may be formed on both sides of the base film.
• a printed wiring board is manufactured by using a hot press or the like to attach a coverlay film to a surface having a wiring portion via an adhesive layer.
• the printed wiring board according to the present invention uses the low-dielectric adhesive composition of the present invention, it enables high-speed transmission of electronic devices and has excellent adhesion stability.
• the adhesive layer of the laminate is brought into contact with the copper wiring, thermal lamination is performed at 80 ° C. to 200 ° C., and the adhesive layer is removed by after-curing. There is a way to harden it.
• the after-cure conditions can be, for example, 100° C. to 200° C. and 30 minutes to 4 hours.
• the shape of the copper wiring is not particularly limited, and any suitable shape may be selected as desired.
• a preferred embodiment of the laminate according to the present invention is a shield film.
• a shield film is a film for shielding various electronic devices in order to cut electromagnetic noise that affects various electronic devices such as computers, mobile phones, and analytical instruments and causes malfunctions. Also called electromagnetic wave shielding film.
• the electromagnetic wave shielding film is formed by laminating an insulating resin layer, a metal layer, and an adhesive layer according to the present invention in this order, for example. Since the shielding film according to the present invention uses the low dielectric adhesive composition of the present invention, high-speed transmission of electronic devices is possible, and the adhesive stability with electronic devices is also excellent. .
• a preferred embodiment of the laminate according to the present invention is a printed wiring board with a shield film.
• a printed wiring board with a shielding film is a printed wiring board having a printed circuit on at least one side of a substrate, and the electromagnetic wave shielding film is attached on the printed wiring board.
• a printed wiring board with a shield film includes, for example, a printed wiring board, an insulating film adjacent to the surface of the printed wiring board on which the printed circuit is provided, and the electromagnetic wave shielding film. Since the printed wiring board with a shielding film according to the present invention uses the low-dielectric adhesive composition of the present invention, it enables high-speed transmission of electronic devices and has excellent adhesion stability.
• This copolymer has an acid value of 0 mgKOH/g, a styrene ratio of 30, and a weight average molecular weight of 67,000.
• Styrene Elastomer Containing Carboxy Group The trade name “Kraton FG1901” (maleic acid-modified hydrogenated styrene-butadiene copolymer (maleic acid-modified styrene-ethylenebutylene-styrene copolymer)) manufactured by Kraton Co., Ltd. was used.
• This copolymer has an acid value of 19 mgKOH/g, a styrene ratio of 30, and a weight average molecular weight of 81,000.
• Example 1 Each component constituting the adhesive layer shown in Table 1 was contained in the ratio shown in Table 1, and these components were dissolved in a solvent to prepare a resin varnish, which is an adhesive composition having a solid content concentration of 15% by mass. Each component constituting the resin composition in the adhesive composition is as shown in Table 1.
• the dielectric constant and dielectric loss tangent at a frequency of 28 GHz were measured for the adhesive layer obtained by curing the resin varnish of Example 1.
• the relative dielectric constant and dielectric loss tangent of the adhesive layer were determined by the open resonator method using a network analyzer MS46122B (manufactured by Anritsu) and an open resonator Fabry-Perot DPS-03 (manufactured by KEYCOM) at a temperature of 23°C. , and a frequency of 28 GHz.
• a resin varnish is applied to the release film, then the film with the coating film is left standing in an oven and dried at 110 ° C. for 4 minutes to obtain a B-stage adhesive layer (thickness 50 ⁇ m ) was formed.
• this adhesive layer was thermally laminated at 150° C.
• the resin varnish prepared above is applied to the surface of the base film, dried in an oven at 130° C. for 4 minutes, and the solvent is volatilized to form an adhesive layer (15 ⁇ m), and the base film with adhesive (adhesion A laminated body with an agent) was obtained.
• the adhesive layer of the laminate with adhesive is stacked so that it is in contact with the glossy surface of the electrolytic copper foil, and pressed at 180 ° C. under pressure (3 MPa) and 10 hPa for 3 minutes using a vacuum press, and at 200 for 1 hour. After curing, the adhesive layer was cured to obtain a laminate with an adhesive after curing.
• the adhesive force (N/cm) between the electrodeposited copper foil and the base film was measured for the laminated body with the adhesive after curing in Example 1.
• a chemical resistance test was performed on the laminated body with an adhesive after curing in Example 1.
• Adhesion strength was determined by cutting the laminate with adhesive after curing into a test specimen with a width of 25 mm, and peeling at a peel speed of 0.3 m / min in accordance with JIS Z0237: 2009 (adhesive tape/adhesive sheet test method). Adhesion was measured by measuring the peel strength when the electrolytic copper foil was peeled off from the adhesive-attached substrate film fixed to the support at an angle of 180°.
• solder heat resistance test In the solder heat resistance test, the laminate with adhesive after curing is cut into a 30 mm ⁇ 30 mm test specimen, and the base film surface is floated in a solder bath at 288 ° C. for 10 seconds ⁇ 3 times, and the adhesive layer Appearance abnormalities such as swelling and peeling were confirmed.
• the heat resistance of the laminate was evaluated according to the following evaluation criteria. ⁇ No abnormality (no dissolution). x: Partially or completely peeled off.
• Table 1 shows each measurement result.
• Example 2 to 4 Laminates of Examples 2 to 4 were produced in the same manner as in Example 1, except that the types and amounts of the components constituting the adhesive layer were changed as shown in Table 1. . Evaluation similar to Example 1 was performed with respect to the produced laminated body. Table 1 shows the results.
• Comparative Examples 1 to 4 Laminates of Comparative Examples 1 to 4 were produced in the same manner as in Example 1, except that the types and amounts of the components constituting the adhesive layer were changed as shown in Table 1. . Evaluation similar to Example 1 was performed with respect to the produced laminated body. Table 1 shows the results.
• the adhesive layer made of the adhesive composition of the present invention exhibits good electrical properties (dielectric properties) compatible with 5G, and adhesion, heat resistance, and chemical resistance (solvent resistance). It is also excellent in sex.
• a laminate having an adhesive layer comprising the adhesive composition of the present invention is suitable for manufacturing FPC-related products for electronic devices such as smartphones, mobile phones, optical modules, digital cameras, game machines, laptop computers, and medical instruments. can be used for

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• 2022
  • 2022-05-23 JP JP2023525733A patent/JPWO2022255137A1/ja active Pending
  • 2022-05-23 WO PCT/JP2022/021050 patent/WO2022255137A1/ja not_active Ceased

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