Resin composition for high frequency, prepreg, metal clad laminate, laminate sheet and printed circuit board using the same

Abstract

The present invention provides a resin composition comprising a modified dicyclopentadiene (DCPD) epoxy resin and at least two types of curing agents, wherein the at least two types of curing agents comprise a styrene-maleic anhydride polymer (SMA) and a benzoxazine-based compound, and a prepreg, a metal foil laminate, and a printed circuit board using the resin composition. In the present invention, low dielectric properties, a high glass transition temperature (Tg), heat resistance, and good adhesion can be simultaneously achieved while securing low manufacturing costs.

Description

Technology Field

[0001] The present invention relates to a novel resin composition having excellent general properties such as dielectric properties, glass transition temperature, heat resistance, and adhesive properties, along with low manufacturing costs, and to prepregs, metal foil laminates, laminated sheets, and printed circuit boards using the same. Background Technology

[0003] Recently, electronic components and information and communication devices, including semiconductor elements, have shown a trend toward higher signal bandwidths. In this context, electrical signal transmission loss is proportional to the dielectric loss tangent and frequency. Consequently, as the frequency increases, transmission loss grows, leading to signal attenuation and a decline in the reliability of signal transmission. Furthermore, transmission loss can be converted into heat, potentially causing heat generation issues. Therefore, insulating materials with very small dielectric loss tangents are required in the high-frequency range.

[0004] Furthermore, as the demand for high integration, miniaturization, and high performance of semiconductor devices increases, there is a need for high density and simplified wiring spacing in the integrated circuits and printed circuit boards used in the manufacture of semiconductor devices. To achieve this, it is desirable to use materials with low dielectric properties that can accelerate signal transmission speeds and reduce transmission losses.

[0005] As a material with the above low dielectric properties, fluoropolymer resins have conventionally been mainly used as the base resin. However, fluoropolymer resins are expensive and have a high melting point, which necessitates a press at high temperature and high pressure, posing manufacturing problems. Consequently, when using them to manufacture prepregs, costs are high and moldability is poor. Additionally, cyanate esters have been used as curing agents, but since these cyanate ester curing agents are expensive materials, this can lead to a deterioration in economic efficiency and productivity. The problem to be solved

[0007] The present invention was devised to solve the aforementioned problems, and the technical objective is to provide a novel resin composition with excellent general properties such as dielectric properties, glass transition temperature, heat resistance, and adhesive properties while reducing costs by using at least two types of curing agents instead of the conventional expensive cyanate ester curing agent.

[0008] In addition, the present invention has another technical objective of providing a prepreg, a metal foil laminate, a laminated sheet, and a printed circuit board including the same using the aforementioned resin composition.

[0009] Other objects and advantages of the present invention may be more clearly explained by the following detailed description of the invention and claims. means of solving the problem

[0011] To achieve the above objective, the present invention provides a resin composition comprising a modified dicyclopentadiene (DCPD) epoxy resin and at least two types of curing agents, wherein the at least two types of curing agents comprise a styrene-maleic anhydride copolymer (SMA) and a benzoxazine-based compound.

[0012] In one embodiment of the present invention, the modified dicyclopentadiene epoxy resin may have at least one of an oxazolidinone modification rate of 30% or less; and an epoxy equivalent of 200 to 600 g / eq.

[0013] For example, in one embodiment of the present invention, the styrene-maleic anhydride copolymer (SMA) may be an alpha-methyl styrene-maleic anhydride copolymer (alpha-methyl-SMA).

[0014] For example, in one embodiment of the present invention, the alpha-methyl styrene-maleic anhydride copolymer has a weight-average molecular weight (Mw) of 5,000 to 20,000 g / mol, and the molar ratio of alpha-methyl styrene to maleic anhydride may be 1 to 10:1.

[0015] For example, in one embodiment of the present invention, the ratio of the styrene-maleic anhydride copolymer (SMA) to the benzoxazine-based compound used may be 1:0.2 to 3.0 by weight.

[0016] For example, in one embodiment of the present invention, the resin composition may further include at least one of an inorganic filler; a curable catalyst; and a flame retardant.

[0017] For example, in one embodiment of the present invention, the resin composition may comprise, based on the total weight (e.g., 100 parts by weight) of the epoxy resin and the curing agent, 20 to 70 parts by weight of modified dicyclopentadiene (DCPD) epoxy resin; 10 to 40 parts by weight of styrene-maleic anhydride copolymer (SMA); 10 to 40 parts by weight of a benzoxazine-based compound; 5 to 25 parts by weight of a flame retardant; 0.1 to 10 parts by weight of a curable catalyst; and 35 to 65 parts by weight of an inorganic filler.

[0018] For example, in one embodiment of the present invention, the resin composition may have a dielectric constant (Dk) of 4.0 or less or a dielectric loss (Df) of 0.01 or less in a high frequency band of 1 GHz to 20 GHz after curing, and a glass transition temperature (Tg) of 145°C or higher.

[0019] In addition, the present invention provides a prepreg comprising a fiber substrate; and a cured product of a resin composition impregnated in the fiber substrate.

[0020] For example, in one embodiment of the present invention, the fiber substrate may include one or more selected from the group consisting of glass fiber, glass paper, glass fiber nonwoven fabric (glass web), glass cloth, aramid fiber, aramid paper, polyester fiber, carbon fiber, inorganic fiber, and organic fiber.

[0021] In addition, the present invention provides a metal foil laminate comprising a metal foil substrate; and a resin layer formed on one or both sides of the metal foil substrate, wherein the resin composition is cured.

[0022] In addition, the present invention provides a laminated sheet comprising a polymer film substrate; and a resin layer formed on one or both sides of the polymer film substrate, wherein the resin composition is cured.

[0023] Furthermore, the present invention provides a printed circuit board comprising the aforementioned prepreg or metal foil laminate. Effects of the invention

[0025] According to one embodiment of the present invention, by using at least two types of curing agents including styrene-maleic anhydride copolymer (SMA) and benzoxazine instead of conventional cyanate ester curing agents, excellent properties in terms of dielectric properties, glass transition temperature (Tg), heat resistance, and adhesion can be achieved while simultaneously lowering manufacturing costs.

[0026] In addition, in the present invention, by adopting a modified dicyclopentadiene (DCPD) epoxy resin as a non-fluorine resin used in combination with the two or more curing agents described above, economic efficiency and moldability can be improved.

[0027] Accordingly, the resin composition according to the present invention can be usefully used as a printed circuit board and / or its material (e.g., high frequency loss grade server) used in various electrical and electronic devices such as mobile communication devices handling high frequency signals of 1 GHz or higher (particularly 10 GHz), network-related electronic devices such as base station devices, servers, routers, and large computers.

[0028] The effects according to the present invention are not limited to those exemplified above, and a wider variety of effects are included in this specification. Specific details for implementing the invention

[0030] The present invention will be described in detail below.

[0031] All terms used in this specification (including technical and scientific terms) may be used in a meaning that is commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0032] Furthermore, throughout the specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Also, "cured product" refers to everything formed by curing the composition.

[0034] Since the dielectric loss of an electrical signal is proportional to the product of the relative permittivity of the insulating layer forming the circuit, the dielectric loss tangent, and the frequency of the electrical signal, the dielectric loss increases as the frequency of the electrical signal increases. Accordingly, in order to be used as an insulating layer for high-frequency printed circuit boards, it is required to use a material with low permittivity and a dielectric loss factor (dielectric loss). Conventionally, fluorinated resins were used to satisfy low dielectric properties; however, due to their high melting points, these fluorinated resins require high-temperature extrusion molding at temperatures above 300°C, resulting in high manufacturing costs and reduced moldability. Furthermore, the use of expensive cyanate ester curing agents leads to a deterioration in economic efficiency and productivity.

[0035] In order to provide a resin composition that can be usefully used for printed circuit boards, particularly for high-frequency applications or for materials included therein, the present invention mixes at least two types of curing agents including styrene-maleic anhydride copolymer (SMA) and benzoxazine, and uses a modified DCPD epoxy resin as the main resin.

[0036] DCPD epoxy resin is not only a non-fluorinated resin but also possesses a larger volume compared to conventional epoxy resins, thereby enabling low dielectric properties. In particular, in the present invention, by modifying the epoxy groups within the molecule into a specific functional group (e.g., oxazolidinone) and controlling the modification rate within a specific range, the low dielectric properties can be further enhanced and the glass transition temperature (Tg) can be improved.

[0037] In addition, among the two types of curing agents, the dielectric properties can be lowered further due to the styrene groups contained in the styrene-maleic anhydride copolymer, and the benzoxazine-based compound can compensate for and increase the low glass transition temperature (Tg) caused by the styrene groups.

[0038] Accordingly, the resin composition of the present invention can secure excellent properties such as dielectric properties, glass transition temperature (Tg), heat resistance, and adhesion while reducing manufacturing costs, and thus can be usefully applied as a material for constituting products such as high-frequency communication devices, servers, and semiconductor devices.

[0040] <Resin Composition>

[0041] A resin composition according to one embodiment of the present invention is a thermosetting resin composition that is usefully usable as a (multilayer) printed circuit board and / or material thereof for communication, server, or network devices for high-frequency applications (e.g., high frequency loss grade server).

[0042] In one specific example, the resin composition comprises a modified dicyclopentadiene (DCPD) epoxy resin; and at least two curing agents, including a styrene-maleic anhydride copolymer (SMA) and a benzoxazine-based compound, as essential components. Optionally, it may further include inorganic fillers, curable catalysts, flame retardants, and conventional additives known in the art.

[0043] Below, the components constituting the resin composition are as follows.

[0044] Modified Dicyclopentadiene (DCPD) Epoxy Resin

[0045] One of the components of the resin composition according to the present invention is an epoxy resin modified with oxazolidinone groups while having a dicyclopentadiene (DCPD) structure within the molecule.

[0046] Modified epoxy resins with a DCPD structure can achieve low dielectric properties as they possess a larger volume compared to conventional epoxy resins. Additionally, they can improve the glass transition temperature (Tg) of the resin composition and reduce the water absorption rate.

[0047] The above modified DCPD epoxy resin can be represented by the following chemical formula 1.

[0048]

[0049] In the above formula,

[0050] X is an oxazolidinone group, and

[0051] Y is an epoxy group, and

[0052] n is an integer between 1 and 10, specifically an integer between 3 and 7.

[0053] The above modified DCPD epoxy resin can be further specified by the following chemical formula 1a.

[0054] [Chemical Formula 1a]

[0055]

[0056] In the above formula,

[0057] Multiple Rs are identical or different, and each independently hydrogen, C1 to C 40 alkyl group of, C6 to C 40 It is Arilgi of, and

[0058] The above alkyl group and aryl group may each be independently substituted with deuterium and cyano group, and n is an integer between 1 and 10, specifically an integer between 3 and 7.

[0059] The modified DCPD epoxy resin according to the present invention has a structure in which oxazolidinone groups are located at both ends of the molecular structure as described in Chemical Formula 1a above, and an epoxy group is present in the middle. When oxazolidinone groups, which have a large volume structure, are introduced at both ends of the molecular structure in this way, the molar polarization rate per unit volume is lowered, thereby enabling low dielectric properties.

[0060] Meanwhile, the epoxy ring generates secondary OH groups through the curing reaction, thereby increasing polarity. In contrast, the present invention positions the aforementioned epoxy ring in the middle of the molecular structure to reduce the functional groups of the epoxy ring associated with polarity, thereby enabling a synergistic effect of low dielectric properties. Furthermore, due to the structure having high thermal stability, it can also have advantageous effects in terms of heat resistance.

[0061] For example, the modified DCPD epoxy resin may have an oxazolidinone modification rate of 30% or less, and for example, may be 10 to 30%. In addition, the modified DCPD epoxy resin may have an epoxy equivalent of 200 to 600 g / eq., specifically 300 to 500 g / eq., and more specifically 300 to 400 g / eq. If the modification rate of the modified DCPD epoxy resin exceeds a predetermined range, the equivalent increases, resulting in a lower curing density, which may lead to a weakening of thermal properties. In contrast, the present invention allows for lower dielectric properties due to a large volume by controlling the modification rate within a predetermined range, while simultaneously improving thermal properties.

[0062] As another specific example, the weight-average molecular weight (Mw) of the modified DCPD epoxy resin may be 700 to 2,500 g / mol, and specifically 1,000 to 2,000 g / mol.

[0063] In the resin composition according to the present invention, the content of the modified DCPD epoxy resin is not particularly limited and can be appropriately adjusted considering the physical properties of the resin composition. For example, the modified DCPD epoxy resin may be 20 to 70 parts by weight based on 100 parts by weight of a mixture of the epoxy resin and a curing agent, and specifically, may be 30 to 65 parts by weight. When the content of the modified DCPD epoxy resin falls within the aforementioned range, low dielectric properties can be exhibited while simultaneously improving thermal properties.

[0065] Styrene-maleic anhydride copolymer (SMA)

[0066] Another component of the resin composition according to the present invention is a styrene-maleic acid anhydride copolymer (SMA).

[0067] Styrene-maleic anhydride copolymer (SMA) contains styrene groups within the molecule, which not only provides excellent dielectric properties but also allows it to replace expensive cyanate curing agents, making it economical. The styrene-maleic anhydride copolymer can be represented by the following chemical formula 2.

[0068]

[0069] In the above formula,

[0070] x is an integer between 35 and 50, and n is an integer between 40 and 60.

[0071] Meanwhile, while styrene-maleic anhydride copolymers can improve the dielectric properties of a resin composition, the inclusion of styrene groups within the molecule may cause a decrease in the glass transition temperature (Tg) of the composition. To address this, the present invention adopts an alpha-methyl styrene-maleic anhydride copolymer in which a methyl group is introduced at a specific position (e.g., side) to compensate for and increase the low glass transition temperature (Tg).

[0072] For example, the alpha-methyl styrene-maleic anhydride copolymer (alpha methyl SMA) can be embodied by the following chemical formula 2a.

[0073] [Chemical Formula 2a]

[0074]

[0075] As another specific example, the alpha-methyl styrene-maleic anhydride copolymer may have a weight-average molecular weight (Mw) of 5,000 to 20,000 g / mol, specifically 5,000 to 15,000 g / mol, and more specifically 7,000 to 12,000 g / mol. In addition, the content of an anhydride included in the copolymer may be 40 weight% or less, specifically 20 to 30 weight%. Furthermore, in the copolymer, the molar ratio of alpha-methyl styrene to maleic anhydride may be 1 to 10:1, specifically 1 to 5:1, and more specifically 3 to 5:1.

[0076] In the resin composition according to the present invention, the content of the styrene-maleic anhydride copolymer is not particularly limited and can be appropriately adjusted considering the physical properties of the resin composition. For example, the styrene-maleic anhydride copolymer may be in an amount of 10 to 40 parts by weight based on 100 parts by weight of the mixture of the epoxy resin and the curing agent, and specifically, may be in an amount of 10 to 30 parts by weight. When the content of the styrene-maleic anhydride copolymer falls within the aforementioned range, thermal properties can be improved while increasing economic efficiency.

[0078] Benzooxazine-based compounds

[0079] Another component of the resin composition according to the present invention is a benzoxazine-based compound.

[0080] Benzoxazine-based compounds are used to compensate for the low glass transition temperature (Tg) characteristics of styrene-maleic anhydride copolymer (SMA) due to the styrene groups. These benzoxazine-based compounds include all compounds having a benzoxazine ring or thermosetting resins having said compounds as a main component, and specifically, are not particularly limited as long as they are resins having a benzoxazine ring and curing by the ring-opening reaction of the benzoxazine ring.

[0081] The above-mentioned benzoxazine-based compound is a condensation product of an oxazine and a benzene ring, and can generally be synthesized by reacting phenols, amines, and formaldehyde. In the present invention, a compound having a single benzoxazine ring (ring) in the molecule, a compound having a benzoxazine structure at both ends, or a polyvalent oxazine compound having multiple benzoxazine rings in the molecule may be used, and specifically, it may be represented by the following chemical formula 3.

[0082]

[0083] In the above formula,

[0084] R1 and R2 are identical or different from each other, and each independently hydrogen, C1 to C 40 alkyl group of, C6 to C 40 It is Arilgi of, and

[0085] The above alkyl and aryl groups can each be independently substituted with deuterium, halogen, and cyano groups.

[0086] For example, the above benzoxazine-based compound can be further specified by the following chemical formula 3a.

[0087] [Chemical Formula 3a]

[0088]

[0089] The above-mentioned benzoxazine-based resin can be ring-opened polymerized and cured by heating to provide a cured product with excellent heat resistance and flame retardancy. Additionally, when reacted with a modified DCPD epoxy resin, it can form a cured product with a high crosslinking density and excellent flame retardancy and toughness. Furthermore, while benzoxazine-based resins of various structures can be applied, using a BPF-type benzoxazine-based resin is preferable due to its excellent hygroscopicity and reactivity.

[0090] In the resin composition according to the present invention, the content of the benzoxazine-based resin may be 5 to 50 parts by weight based on 100 parts by weight of a mixture of epoxy resin and curing agent, and preferably 10 to 40 parts by weight. When the content of the benzoxazine-based resin falls within the aforementioned range, the curability, flame retardancy, low moisture absorption, and adhesive strength of the resin composition are good.

[0091] Meanwhile, in the present invention, by using a modified DCPD epoxy resin and a styrene-maleic anhydride and a benzoxazine-based compound as at least two types of curing agents for composite curing, not only are low dielectric properties due to the styrene groups exhibited, but excellent heat resistance can also be secured by compensating for and raising the low glass transition temperature (Tg) caused by the styrene groups. At this time, the ratio of the styrene-maleic anhydride copolymer (SMA) to the benzoxazine-based compound is not particularly limited, and for example, is a weight ratio of 1:0.2 to 3.0, specifically 1:0.5 It may be up to 2.0 weight ratio.

[0093] Flame retardant

[0094] The resin composition according to the present invention may further include a flame retardant as needed.

[0095] The above flame retardants may be used without limitation as they are conventionally known in the field to enhance flame retardancy. Examples include halogen flame retardants containing bromine or chlorine; phosphorus-based flame retardants such as phosphates, phosphonates, phosphinates, phosphine oxides, and phosphazenes; antimony-based flame retardants such as antimony trioxide; and inorganic flame retardants such as metal hydroxides such as aluminum hydroxide and magnesium hydroxide. It is preferable to use phosphorus-based flame retardants that do not reduce heat resistance and dielectric properties, and specific examples include triphenyl phosphate, trikexyl phosphate, trisdichloropropyl phosphate, and phosphazenes.

[0096] In the present invention, the content of the flame retardant is not particularly limited and can be appropriately adjusted within a content range known in the art. Considering the physical properties of the thermosetting resin composition, the content may be 5 to 25 parts by weight based on 100 parts by weight of the mixture of the epoxy resin and the curing agent, and preferably 7 to 20 parts by weight.

[0098] Catalyst

[0099] In the present invention, conventional curable catalysts known in the art (e.g., curing accelerators) may be further included as needed.

[0100] The above catalyst can be appropriately selected and used depending on the type of epoxy resin and curing agent. Non-limiting examples of usable catalysts include amine-based, phenol-based, and imidazole-based curing accelerators, and specific examples include amine complexes of boron trifluoride, imidazole derivatives, and organic acids such as phthalic anhydride and trimellitic anhydride. A preferred example of a usable catalyst is an imidazole derivative curing accelerator, specifically 1-methylimidazole, 2-methylimidazole, 2-ethyl 4-methylimidazole, 2-phenylimidazole, 2-phenyl 4-methylimidazole, cyanoethylation derivatives thereof, carboxylic acid derivatives, hydroxymethyl group derivatives, etc. The above catalyst may be used alone or two or more may be used in combination.

[0101] In addition, organometallic salts or organometallic complexes comprising one or more metals selected from the group consisting of iron, copper, zinc, cobalt, lead, nickel, manganese, and tin may be used. Specific examples of usable organometallic salts or organometallic complexes include iron napthenates, copper napthenates, zinc napthenates, cobalt napthenates, nickel napthenates, manganese napthenates, tin napthenates, zinc octanoates, tin octanoates, iron octanoates, copper octanoates, zinc 2-ethylhexanates, lead acetylacetonates, cobalt acetylacetonates, or dibutyltin maleates, and may be used alone or in a mixture of two or more.

[0102] In the present invention, the content of the catalyst is not particularly limited and can be appropriately adjusted within a content range known in the art. Considering the physical properties of the thermosetting resin composition, the amount may be 0.1 to 10 parts by weight based on 100 parts by weight of the mixture of the epoxy resin and the curing agent, specifically 0.5 to 10 parts by weight, and preferably 0.5 to 7 parts by weight.

[0104] Weapon Filler

[0105] The resin composition according to the present invention may further include conventional inorganic fillers known in the art, as needed.

[0106] Inorganic fillers can effectively improve the bending properties, low expansion, mechanical strength (toughness), and low stress of the final product by increasing mechanical properties and reducing the difference in the coefficient of thermal expansion (CTE) between the resin layer and other layers.

[0107] Non-limiting examples of usable inorganic fillers include silicas such as natural silica, fused silica, amorphous silica, and crystalline silica; boehmite, alumina, talc, spherical glass, calcium carbonate, magnesium carbonate, magnesia, clay, calcium silicate, titanium oxide, antimony oxide, glass fiber, aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, barium zirconate, calcium zirconate, boron nitride, silicon nitride, talc, and mica. These inorganic fillers may be used alone or in combination of two or more types. Among the above inorganic fillers, fused silica, which exhibits a low coefficient of thermal expansion, is preferred.

[0108] The size of the inorganic filler is not specifically limited, but considering dispersibility, the average particle size (D 50 It is preferable that the thickness is about 0.5 to 5 μm. In addition, the surface of the inorganic filler may be treated with a silane coupling agent. Such silane coupling agents may be conventional components known in the art, and may contain vinyl groups and / or allyl groups, etc. When the surface is treated with such a silane coupling agent, the compatibility with the resin is excellent, which can improve the dielectric properties, heat resistance, processability, etc. of the resin composition.

[0109] In the present invention, the content of the inorganic filler is not subject to any particular limitation and can be appropriately adjusted by considering the aforementioned bending characteristics, mechanical properties, etc. For example, it may be 35 to 65 parts by weight based on 100 parts by weight of the mixture of the epoxy resin and the curing agent, and specifically, it may be 35 to 60 parts by weight. If the content of the inorganic filler is excessive, it may be disadvantageous to moldability.

[0111] Other ingredients

[0112] The resin composition according to the present invention may further include, as necessary and without compromising the inherent properties of the resin composition, various polymers such as other thermosetting resins or thermoplastic resins not described above and their oligomers, solid rubber particles, or other additives such as ultraviolet absorbers, antioxidants, polymerization initiators, dyes, pigments, dispersants, thickeners, leveling agents, etc.

[0113] Examples include organic fillers such as silicone powder, nylon powder, and fluorine powder; thickeners such as olben and benton; silicone-based, fluorine-based, and polymer-based defoaming agents or leveling agents; adhesion-imparting agents such as imidazole-based, thiazole-based, triazole-based, silane coupling agents, epoxysilane, aminosilane, alkylsilane, and mercaptosilane; coloring agents such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, and carbon black; release agents such as higher fatty acids, higher fatty acid metal salts, and ester-based waxes; and stress-relieving agents such as modified silicone oil, silicone powder, and silicone resin. In addition, it may include additives commonly used in thermosetting resin compositions used in the production of electronic devices (particularly printed circuit boards).

[0114] The above resin composition may further incorporate a thermoplastic resin for purposes such as imparting suitable flexibility to the resin composition after curing. Non-limiting examples of usable thermoplastic resins include phenoxy resin, polyvinyl acetal resin, polyimide, polyamideimide, polyethersulfone, polysulfone, etc. Any one of these thermoplastic resins may be used alone, or two or more may be used in combination.

[0115] In a preferred example of the present invention, the resin composition comprises, based on the total weight (e.g., 100 parts by weight) of the epoxy resin and the curing agent, 20 to 70 parts by weight of modified dicyclopentadiene (DCPD) epoxy resin; 10 to 40 parts by weight of styrene-maleic anhydride copolymer (SMA); 10 to 40 parts by weight of a benzoxazine-based compound; 5 to 25 parts by weight of a flame retardant; and 0.1 parts by weight of a curable catalyst. It may include up to 10 parts by weight; and 35 to 65 parts by weight of inorganic filler. Additionally, it may further include organic solvents or other components to satisfy a total of 100 parts by weight. Here, the content standard for each component is based on the total weight of the epoxy resin and the curing agent (e.g., SMA and benzoxazine) combined, but is not specifically limited thereto, and may also refer to the total weight of the composition (e.g., 100 parts by weight) or the total weight of the varnish containing the organic solvent.

[0116] In addition, the content of the above-mentioned curable catalyst may be appropriately varied according to the gel time of the resin composition. At this time, the gel time is based on the time measured by placing 100 mg of the resin composition on a hot plate at 170°C, stirring it with a toothpick and a Teflon rod, and lifting it until the resin stretches out like a thread and is no longer pulled along.

[0117] Ordinary organic solvents known in the industry may be used without limitation. For example, various organic solvents such as acetone, cyclohexanone, methyl ethyl ketone, toluene, xylene, and tetrahydrofuran may be mixed as desired. Here, the content of the organic solvent may be within the range of the remainder satisfying the total amount of the composition (e.g., 100 parts by weight of the entire varnish) and is not particularly limited.

[0118] The resin composition of the present invention configured as described above can secure low dielectric properties, a high glass transition temperature (Tg), and thermal properties while reducing manufacturing costs.

[0119] For one specific example, the resin composition may have a dielectric constant (Dk) of 4.0 or less, a dielectric loss (Df) of 0.01 or less, and a glass transition temperature (Tg) of 145°C or higher in a high frequency band of 1 GHz to 20 GHz after curing. More specifically, the dielectric constant (Dk) may be 3.8 or less, the dielectric loss (Df) may be 0.07 or less, and the glass transition temperature (Tg) may be 180 to 195°C.

[0121] Prepreg

[0122] One embodiment of the present invention is a prepreg comprising the aforementioned resin composition or a cured product thereof. This prepreg is distinguished from conventional prepregs in that it comprises a thermosetting resin composition of the composition described above and can be used in a printed circuit board described below.

[0123] One specific example of the prepreg comprises a fiber substrate; and the aforementioned resin composition impregnated into the fiber substrate. Here, the resin composition may be a resin varnish in a form dissolved or dispersed in a solvent, or a cured product of the resin composition. Such cured products include uncured products, semi-cured products, and / or fully cured products.

[0124] The fiber substrate includes conventional inorganic fiber substrates, organic fiber substrates, or mixtures thereof that are flexible and can be bent at will. The fiber substrate may be selected at will based on the intended use or performance.

[0125] Non-limiting examples of usable fiber substrates include glass fibers (inorganic fibers) such as E-glass, D-glass, S-glass, NE-glass, T-glass, Q-glass, etc.; organic fibers such as glass paper, glass fiber nonwoven fabric (glass web), glass cloth, aramid fiber, aramid paper, polyimide, polyamide, polyester, aromatic polyester, fluoropolymer, etc.; carbon fibers, paper, inorganic fibers, or mixtures of one or more of these. Examples of the forms of the fiber substrates include woven or nonwoven fabrics made of the aforementioned fibers, etc.; roving, chopped strand mat, surfacing mat, woven fabrics, nonwoven fabrics, mats made of metal fibers, carbon fibers, mineral fibers, etc. These substrates may be used alone or in combination of two or more types. When reinforced fiber substrates are combined, the stiffness and dimensional stability of the prepreg can be improved. The thickness of the fiber substrate is not particularly limited and may be, for example, in the range of about 0.01 mm to 0.3 mm.

[0126] The prepreg according to the present invention may be manufactured according to methods known in the art. In one embodiment, the prepreg refers to a sheet-shaped material in which resin is impregnated within a fiber substrate by coating or impregnating a sheet-shaped fiber substrate or a glass substrate made of fibers with the resin composition or resin composition varnish and then curing it to a B-stage (semi-cured state) by heating. At this time, the temperature and time for heating the fiber substrate impregnated with the resin composition of the present invention are not particularly limited; for example, the temperature is preferably about 20 to 200°C (specifically 70 to 170°C), and the time is preferably about 1 to 10 minutes.

[0127] In addition to the method described above, the prepreg of the present invention may also be manufactured by methods such as the solvent method or the hot melt method.

[0128] The solvent method is a method in which a fiber substrate is impregnated with a resin composition varnish formed by dissolving a thermosetting resin composition for prepreg formation in an organic solvent, and then dried. When employing this solvent method, a resin varnish is generally used. Examples of methods for impregnating the fiber substrate with the resin composition include immersing the substrate in the resin varnish, applying the resin varnish to the substrate using various coaters, or spraying the resin varnish onto the substrate. In this case, immersing the fiber substrate in the resin varnish is preferable as it can improve the impregnation of the resin composition into the fiber substrate. Examples of organic solvents that can be used when preparing the resin composition varnish above include ketones such as acetone, methyl ethyl ketone, and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellosolve and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and tetrahydrofuran. The above-mentioned organic solvents may be used alone or in combination of two or more types.

[0129] In addition, the hot melt method may be a method in which the resin composition is not dissolved in an organic solvent, and the resin composition is coated onto a release liner with excellent release properties, and then laminated onto a sheet-like fiber substrate or directly coated using a die coater. Furthermore, it may be manufactured by placing an adhesive film made of a thermosetting resin composition on both sides of a sheet-like fiber substrate and then continuously laminating it by heating and pressurizing.

[0130] Since the prepreg of the present invention comprises a resin in which the above-described resin composition is cured, it can exhibit excellent adhesion, heat resistance, and glass transition temperature, as well as improved low dielectric properties and cost reduction effects.

[0132] Metal foil laminate

[0133] One embodiment of the present invention is a metal foil laminate comprising the resin composition or the cured product thereof described above.

[0134] In one specific example, the metal foil laminate comprises a metal foil substrate; and a resin layer formed on one or both sides of the metal foil substrate, wherein the resin composition described above is cured.

[0135] The metal foil may be any metal or alloy known in the industry without limitation. If the metal foil is copper foil, the metal foil laminate formed by coating and drying the thermosetting resin composition according to the present invention may be used as a copper foil laminate (CCL). Preferably, it may be copper foil.

[0136] These copper foils include all copper foils manufactured by rolling and electrolytic methods. The copper foils may be treated with an anti-rust treatment to prevent oxidative corrosion of the surface. Non-limiting examples of available copper foils include CFL (TZA_B, HFZ_B), Mitsui (HSVSP, MLS-G), Nikko (RTCHP), Furukawa, ILSIN, etc.

[0137] In the present invention, the metal foil may have a predetermined surface roughness (Rz) formed on the surface in contact with the resin layer in which the thermosetting resin composition is cured. The range of such surface roughness (Rz) is not particularly limited and, for example, may be 0.6 to 3.0 μm. In addition, the thickness of the metal foil is not particularly limited and, considering the thickness and mechanical properties of the laminated sheet, may be less than 5 μm, and preferably 1 to 3 μm.

[0139] Laminated Sheet

[0140] Another embodiment of the present invention is a laminated sheet comprising the resin composition or the cured product thereof described above.

[0141] In one specific example, the laminated sheet comprises: a polymer film substrate; and a resin layer formed on one or both sides of the polymer film substrate, wherein the thermosetting resin composition described above is cured.

[0142] The above polymer film substrate is not particularly limited as long as it is an insulating film known in the industry. Non-limiting examples of usable polymer film substrates include polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate; polyethylene films; polypropylene films; cellophane; diacetylcellulose films; triacetylcellulose films; acetylcellulose butyrate films; polyvinyl chloride films; polyvinylidene chloride films; polyvinyl alcohol films; ethylene-vinyl acetate copolymer films; polystyrene films; polycarbonate films; polymethylpentene films; polysulfone films; polyetheretherketone films; polyethersulfone films; polyetherimide films; polyimide (PI) films; fluoropolymer films; polyamide films; acrylic resin films; norbornene-based resin films; cycloolefin resin films, etc. Specifically, it may be a polyimide (PI) film, an epoxy resin film, a PET (polyethylene terephthalate) film, a PEN (polyethylene naphthalate) film, etc. These polymer films may be transparent or translucent, and may be colored or uncolored, and can be appropriately selected according to the application. In addition, the polymer film substrate may be a substrate on which silicone release treatment, antistatic treatment, or both silicone release treatment and antistatic treatment are performed on at least one surface.

[0143] The thickness of the polymer film substrate is not particularly limited, and considering the thickness and mechanical properties of the laminated sheet, it may be 1 to 100 μm, and specifically 10 to 80 μm.

[0145] Printed Circuit Board

[0146] Another embodiment of the present invention is a printed circuit board comprising the aforementioned prepreg or metal foil laminate.

[0147] For example, the printed circuit board includes a laminate formed by overlapping two or more of the aforementioned prepregs and then heating and pressing them under normal conditions. This laminate serves as an insulating layer, an adhesive layer, or a coverlay layer in the printed circuit board.

[0148] A printed circuit board according to the present invention can be manufactured according to methods known in the art. For example, in one embodiment, a copper foil can be laminated on one or both sides of the prepreg described above and heated and pressed to form a copper foil laminate, then a through hole is formed in the copper foil laminate and through hole plating is performed, and then the copper foil is etched to form a circuit.

[0149] As the printed circuit board of the present invention configured as described above, since it is manufactured using a prepreg or metal foil laminate comprising a resin in which a resin composition comprising a modified DCPD epoxy resin and at least two types of curing agents is cured, it achieves low dielectric properties while having a high glass transition temperature (Tg) and excellent heat resistance and adhesion. Accordingly, the printed circuit board of the present invention can be usefully used as a printed circuit board and / or material therefor applied to various electrical and electronic devices such as mobile communication devices handling high-frequency signals of 1 GHz or higher, network-related electronic devices such as base station devices, servers, routers, and large computers.

[0151] The present invention will be explained in detail below through examples. However, the following examples are merely illustrative of the present invention, and the present invention is not limited by the following examples.

[0153] [Examples 1-6]

[0154] 1-1. Preparation of Resin Composition

[0155] A resin composition was prepared by mixing DCPD epoxy resin, SMA, benzoxazine, a flame retardant, a catalyst, and an inorganic filler according to the compositions listed in Tables 1 and 2 below. In Table 2 below, the unit of content (amount used) of each component is in parts by weight, based on the total weight of the resin composition (non-volatile components excluding solvent).

[0156] 1-2. Manufacturing of Prepreg

[0157] After impregnating glass fibers with the resin composition prepared above, a prepreg in a semi-cured (B-stage) state was prepared by drying and heating at 165°C for 3 to 10 minutes.

[0158] 1-3. Manufacture of Copper Foil Laminates

[0159] A copper foil laminate with a thickness of 0.1 mm was prepared by laminating 1 ply of the prepreg prepared in Examples 1-2 onto a copper foil and pressing at 200°C for 4 hours.

[0160] 1-4. Manufacture of Printed Circuit Boards

[0161] A photosensitive dry film was applied to the copper foil laminate prepared in Examples 1-3 above by adhering it to the laminate using heat and pressure, and then a printed circuit board (PCB) was manufactured by irradiating it with light using a master film showing the circuit and developing it. The copper foil containing the unnecessary plating film was removed (etched) from the surface of the completed printed circuit board using a highly corrosive chemical to form the circuit.

[0162] composition Detailed specifications Epoxy resin A-1 DCPD Kukdo, KDCPD-130 A-2 Modified DCPD 1 Kukdo, KDL-190 Oxazolidone modification rate 30% or less, epoxy equivalent 350 g / eq. A-3 Modified DCPD 2 Kukdo, Test sample oxazolidone modification rate greater than 0%, epoxy equivalent 500 g / eq. hardener B-1 SMA polyscope, xiran-40 B-2 Allyl SMA Nanokor, Test sample C Benzoic jade photo huntzman, LZ-8260 flame retardant D Phosphorus-based flame retardant Daihachi, PX-200 catalyst E catalyst Shikoku, 2E4MZ (2-ethyl-4-methyl imidazole) Weapon filler F Fused silica Admatechs, SO-C2

[0163] Examples Comparative example 1 2 3 4 5 6 1 2 3 4 A-1 60 60 100 100 A-2 60 60 50 70 40 A-3 60 B-1 20 20 20 10 B-2 20 30 10 20 40 20 C 20 20 20 20 20 20 20 20 30 40 D 10 10 10 10 10 10 10 10 10 10 E 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 F 35 35 35 35 35 35 35 35 35 35 P / S(kgf / cm) 1.0 0.9 0.8 1.1 1.0 0.7 0.8 0.85 1.2 1.3 Tg (°C)(TMA) 185 173 168 192 170 145 150 165 180 185 flame retardant V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 Permittivity (Dk) 3.9 3.9 3.8 4.0 3.9 3.8 4.2 4.2 4.4 4.5 Dielectric loss (Df) 0.007 0.007 0.007 0.01 0.007 0.006 0.01 0.009 0.012 0.014

[0165] [Comparative Examples 1 ~ 4]

[0166] A resin composition, prepreg, copper foil laminate, and printed circuit board were each manufactured in the same manner as in the above example, except that the composition was changed as described in Table 2 above.

[0168] [Experimental Example 1] Evaluation of Physical Properties

[0169] The physical properties of the printed circuit boards prepared in Examples 1 to 6 and Comparative Examples 1 to 4 were evaluated in the following manner, and the results are shown in Table 2 above.

[0170] 1) Measurement of Glass Transition Temperature (Tg)

[0171] The glass transition temperature (Tg) was measured using DMA (Dynamic Mechanical Analysis), TA's Q800, by IPC-TM-650-2. 4. 24. 4 (DMA Method).

[0172] 2) Permittivity and Dielectric Loss

[0173] According to the IPC TM 650 2.5.5.9 evaluation standard, the printed circuit board was immersed in a copper etching solution to remove the copper foil layer, and the dielectric constant and dielectric loss at a frequency of 1 GHz were measured using a dielectric constant measuring device (RF Impedance / Material Analyzer; Agilent).

[0174] 3) Flame retardancy

[0175] A printed circuit board was immersed in a copper etching solution to remove the copper foil layer, and a sample was prepared with a length of 127 mm and a width of 12.7 mm, and then evaluated according to the UL94 test method (V method).

[0176] 4) Peel Strength (P / S)

[0177] According to the evaluation standard of IPC-TM-650 2.4.8, the copper foil layer of the printed circuit board was pulled up from the 90° direction, and the time at which the copper foil layer peeled off was measured and evaluated.

[0178] As a result of the experiment, Examples 1 to 6, which contain modified DCPD epoxy resin and at least two types of curing agents (SMA, benzoxazine), exhibited superior effects in terms of glass transition temperature (Tg), heat resistance, adhesion, and low dielectric constant compared to Comparative Examples 1 to 4, which do not simultaneously contain the aforementioned components.

[0179] In particular, in the case of Example 1, which used a styrene-maleic anhydride copolymer with a methyl group introduced at the alpha position instead of a styrene-maleic anhydride copolymer (SMA) under the same composition, it was found that while it exhibited equivalent properties in terms of dielectric properties, the glass transition temperature (Tg) increased by more than 12°C, indicating a significant improvement in thermal properties. In addition, it was found that when the modification rate of the modified DCPD epoxy resin is controlled within a predetermined range, the curing density increases, thereby exhibiting an synergistic effect on thermal properties.

[0180] Accordingly, the present invention can manufacture a printed circuit board with excellent general properties, such as dielectric properties, heat resistance, and adhesive properties in the high-frequency range, and it was confirmed that it can be usefully utilized as a material for constituting products such as communication devices, servers, and semiconductor devices that require the aforementioned properties.

Claims

Claim 1 A resin composition comprising: a modified dicyclopentadiene (DCPD) epoxy resin; and at least two curing agents, wherein the at least two curing agents comprise a styrene-maleic anhydride copolymer (SMA); and a benzoxazine-based compound, wherein the modified dicyclopentadiene epoxy resin has an oxazolidinone modification rate of 30% or less and is represented by the following chemical formula 1a: [Chemical Formula 1a] In the above formula, multiple Rs are identical or different, and each independently hydrogen, C1 to C 40 The alkyl group of, and C6 to C 40 The alkyl group and the aryl group may each be independently substituted with a substituent selected from the group consisting of deuterium and cyano groups, and n is an integer between 1 and 10. Claim 2 delete Claim 3 In claim 1, the modified dicyclopentadiene epoxy resin is a resin composition having an epoxy equivalent of 200 to 600 g / eq. Claim 4 In claim 1, the styrene-maleic anhydride copolymer (SMA) is a resin composition in which the styrene-maleic anhydride copolymer (alpha methyl-SMA). Claim 5 A resin composition according to claim 4, wherein the alpha-methyl styrene-maleic anhydride copolymer has a weight-average molecular weight (Mw) of 5,000 to 20,000 g / mol and a molar ratio of alpha-methyl styrene to maleic anhydride of 1 to 10:

1. Claim 6 In claim 1, the resin composition wherein the benzoxazine-based compound is represented by the following chemical formula 3: [Chemical Formula 3] In the above formula, R1 and R2 are identical or different from each other, and each independently hydrogen, C1 to C 40 The alkyl group of, and C6 to C 40 The alkyl group and the aryl group may each be independently substituted with a substituent selected from the group consisting of deuterium, halogen, and cyano groups. Claim 7 A resin composition according to claim 1, wherein the ratio of the styrene-maleic anhydride copolymer (SMA) to the benzoxazine-based compound used is 1:0.2 to 3.0 by weight. Claim 8 A resin composition according to claim 1, further comprising at least one of an inorganic filler; a curable catalyst; and a flame retardant. Claim 9 A resin composition according to claim 1, comprising, based on the total weight of the epoxy resin and the curing agent, 20 to 70 parts by weight of modified dicyclopentadiene (DCPD) epoxy resin; 10 to 40 parts by weight of styrene-maleic anhydride copolymer (SMA); 10 to 40 parts by weight of a benzoxazine-based compound; 5 to 25 parts by weight of a flame retardant; 0.1 to 10 parts by weight of a curable catalyst; and 35 to 65 parts by weight of an inorganic filler. Claim 10 The resin composition of claim 1, wherein the resin composition has a dielectric constant (Dk) of 4.0 or less or a dielectric loss (Df) of 0.01 or less in a high-frequency band of 1 GHz to 20 GHz after curing, and a glass transition temperature (Tg) of 145°C or higher. Claim 11 A prepreg comprising a fiber substrate; and a resin composition described in any one of claims 1, 3 to 10 impregnated into the fiber substrate. Claim 12 The prepreg according to claim 11, characterized in that the fiber substrate comprises one or more selected from the group consisting of glass fiber, glass paper, glass fiber nonwoven fabric (glass web), glass cloth, aramid fiber, aramid paper, polyester fiber, carbon fiber, inorganic fiber, and organic fiber. Claim 13 A metal foil laminate comprising: a metal foil substrate; and a resin layer formed on one or both sides of the metal foil substrate, wherein the resin composition described in any one of claims 1, 3 to 10 is cured. Claim 14 A laminated sheet comprising: a polymer film substrate; and a resin layer formed on one or both sides of the polymer film substrate, wherein the resin composition described in any one of claims 1, 3 to 10 is cured. Claim 15 A printed circuit board comprising the prepreg of claim 11. Claim 16 A printed circuit board comprising the metal foil laminate of claim 13.

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