WO2012091320A2

WO2012091320A2 - Epoxy resin compound and radiant heat circuit board using the same

Info

Publication number: WO2012091320A2
Application number: PCT/KR2011/009520
Authority: WO
Inventors: Eun Jin Kim; In Hee Cho; Jae Man Park; Hyun Gyu Park; Yun Ho An; Hae Yeon Kim
Original assignee: Lg Innotek Co., Ltd.
Priority date: 2010-12-27
Filing date: 2011-12-09
Publication date: 2012-07-05
Also published as: WO2012091320A3; KR20120074109A; TW201229083A

Abstract

An epoxy resin compound having an epoxy resin, a hardener, and an inorganic filler as major components is provided. The epoxy resin includes an epoxy resin expressed by Chemical Formula. Therefore, thermal conductivity may be increased by using an epoxy resin including a mesogenic structure that increases crystallinity. Also, a high heat dissipation circuit board may be provided by using the epoxy resin as an insulation material on a printed circuit board.

Description

EPOXY RESIN COMPOUND AND RADIANT HEAT CIRCUIT BOARD USING THE SAME

The present disclosure relates to an epoxy resin compound, and more particularly, to an epoxy resin compound used for an insulation layer of a radiant heat circuit board.

A circuit board is an electrically insulating substrate including circuit patterns and is a substrate for mounting electronic components and the like.

Such electronic components may be heat dissipation devices such as a light-emitting diode (LED) and the heat dissipation device dissipates considerable heat. The heat dissipated from the heat dissipation device increases the temperature of a circuit board, and thus, malfunction and limitations in the reliability of the heat dissipation device are generated. Therefore, a heat dissipation structure for dissipating the heat from the electronic components to the outside is important for the circuit board and the thermal conductivity of an insulation layer formed on the circuit board greatly affects heat dissipation. In order to increase the thermal conductivity of the insulation layer, high density filling of an inorganic filler is necessary and for this purpose, an epoxy resin having excellent low viscosity is suggested.

In generally, bisphenol A-type epoxy resin or bisphenol F-type epoxy resin is widely used as a low viscous epoxy resin. Since these epoxy resins are liquid at room temperature, handling thereof is difficult and there are limitations in heat resistance, mechanical strength, and toughness.

Embodiments provide an epoxy resin compound having a new compound.

Embodiments also provide a radiant heat circuit board having improved thermal efficiency.

In one embodiment, an epoxy resin compound includes: an epoxy resin; a hardener; and an inorganic filler as major components, wherein the epoxy resin includes an epoxy resin of the following Chemical Formula.

[Chemical Formula]

(where n is an integer between 0 and 50)

In another embodiment, a radiant heat circuit board includes: a metal plate; an insulation layer formed on the metal plate; and a circuit pattern formed on the insulation layer, wherein the insulation layer is formed by curing an epoxy resin compound having an epoxy resin, a hardener, and an inorganic filler as major components and the epoxy resin includes an epoxy resin of the above Chemical Formula. According to the present invention, thermal conductivity may be increased by using an epoxy resin including a mesogenic structure that increases crystallinity. Also, a high heat dissipation circuit board may be provided by using the epoxy resin as an insulation material on a printed circuit board. The crystalline epoxy resin has excellent formability and reliability, and improves thermal conductivity, absorption behavior, thermal expansion behavior, and heat resistance.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims.

Fig. 1 is a cross-sectional view illustrating a radiation heat circuit board of the present invention.

Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings to fully explain the present invention in such a manner that it may be easily carried out by a person skilled in the art to which the present invention pertains. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the specification, when it is described that one ‘comprises’ some elements, it should be understood that it may comprise only those elements, or it may comprise other elements as well as those elements if there is no specific limitation.

In the drawings, elements except essential features of the present disclosure are deleted for clarity of description, the dimensions of layers and regions are exaggerated for clarity of illustration, and like reference numerals refer to like elements throughout.

Also, in the descriptions of embodiments, it will be understood that when a part such as a layer, a film, a region, or a plate is referred to as being ‘on’ another part, it can be ‘directly on’ the other part, or intervening parts may also be present. On the contrary, when a part is referred to as being 'directly on' another part, it means that no intervening constituent element is present.

The present invention provides an epoxy resin compound having improved thermal conductivity due to high crystallinity.

Hereinafter, the crystalline epoxy resin compound of the present invention includes an epoxy resin, a hardener, and an inorganic filler as major components.

The epoxy resin includes 12 wt% or more of a crystalline epoxy resin and may include 50 wt% or more of the crystalline epoxy resin.

At this time, the crystalline epoxy resin satisfies the following Chemical Formula.

[Chemical Formula]

(where n is an integer between 0 and 50)

When the use ratio of the crystalline epoxy resin is less than the foregoing ranges, the effects on thermal conductivity or the like are small because the crystalline epoxy resin does not crystallize during hardening.

The epoxy resin includes other typical non-crystalline epoxy resins having two or more epoxy groups in a molecule in addition to the crystalline epoxy resin used as an essential component of the present invention.

Examples of the non-crystalline epoxy resin may be bisphenol A, 3,3’,5,5’-tetramethyl-4,4’-dihydroxydiphenylmethane, 4,4’-dihydroxydiphenylsulfone, 4,4’-dihydroxydiphenylsulfide, 4,4’-dihydroxydiphenylketone, fluorenebisphenol, 4,4’-biphenol, 3,3’,5,5’-tetramethyl-4,4’-dihydroxybiphenyl, 2,2’-biphenol, resorcin, catechol, t-butylcatechol, hydroquinone, t-butyl hydroquinone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated or polyallylated compounds of the foregoing dihydroxynaphthalenes, divalent phenols such as allylated bisphenol A, allylated bisphenol F, or allylated phenol novolac, trivalent or more phenols such as phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, tris-(4-hydroxyphenyl)methane, 1,1,2,2-tetrakis(4-hydroxypheny)ethane, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, a phenol aralkyl resin, a naphthol aralkyl resin, or a dicyclopentadiene-based resin, or a gylcidyl ether compound derived from halogenated bisphenols such as tetrabromobisphenol A. The foregoing non-crystalline epoxy resins may be used in combination of one or more.

Any hardener generally known as an epoxy resin hardener may be used as the hardener used in the epoxy resin compound of the present invention, and a phenol-based hardener may be used.

The phenol-based hardener is a single compound among phenolic compounds, wherein a phenolic resin is included in addition to the phenolic compound.

Particular examples of the phenol-based hardener may be bisphenol A, bisphenol F, 4,4’-dihydroxydiphenylmethane, 4,4’-dihydroxydiphenylether, 1,4-bis(4-hydroxyphenoxy)benzene, 1,3-bis(4-hydroxyphenoxy)benzene, 4,4’-dihydroxydiphenylsulfide, 4,4’-dihydroxydiphenylketone, 4,4’-dihydroxydiphenylsulfone, 4,4’-dihydroxybiphenyl, 2,2’-dihydroxybiphenyl, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, phenol novolac, bisphenol A novolac, o-cresol novolac, m-cresol novolac, p-cresol novolac, xylenol novolac, poly-p-hydroxystyrene, hydroquinone, resorcin, catechol, t-butylcatechol, t-butyl hydroquinone, fluoroglycinol, pyrogallol, t-butylpyrogallol, allylated pyrogallol, polyallylated pyrogallol, 1,2,4-benzenetriol, 2,3,4-trihydroxybenzophenone, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,4-dihydroxynaphthalene, 2,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,8-dihydroxynaphthalene, allylated or polyallylated compounds of the foregoing dihydroxynaphthalenes, allylated bisphenol A, allylated bisphenol F, or allylated phenol novolac.

The hardener may be used in combination of two or more hardeners.

Meanwhile, a generally known hardener may be used in addition to the phenol-based hardener. For example, an amine-based hardener, an acid anhydride-based hardener, a polymercaptan-based hardener, a polyaminoamide-based hardener, an isocyanate-based hardener, or a block isocyanate-based hardener may be used. A mixing amount of the foregoing hardeners may be properly determined in consideration of the types of mixed hardeners or the physical properties of a thermally conductive epoxy resin molded article obtained.

Particular examples of the amine-based hardener may be aliphatic amines, polyether polyamines, cycloaliphatic amines, and aromatic amines, and examples of the aliphatic amines may be ethylenediamine, 1,3-diaminopropane, 1,4-diaminopropane, hexamethylenediamine, 2,5-dimethylhexamethylenediamine, trimethylhexamethylenediamine, diethylenetriamine, iminobispropylamine, bis(hexamethylene)triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-hydroxyethyl ethylenediamine, tetra(hydroxyethyl)ethylenediamine, etc. Examples of the polyether polyamines may be triethylene glycol diamine, tetraethylene glycol diamine, diethylene glycol bis(propylamine), polyoxypropylenediamine, polyoxypropylenetriamine, etc. Examples of the cycloaliphatic amines may be isophoronediamine, methacenediamine, N-aminoethylpiperazine, bis(4-amino-3-methyldicyclohexyl)methane, bis(aminomethyl)cyclohexane, 3,9-bis(3-aminopropyl)2,4,8,10-tetraoxaspiro(5,5)undecane, norbornenediamine, etc. Examples of the aromatic amines may be tetrachloro-p-xylenediamine, m-xylenediamine, p-xylenediamine, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, 2,4-diaminoanisole, 2,4-toluenediamine, 2,4-diaminodiphenylmethane, 4,4’-diaminodiphenylmethane, 4,4’-diamino-1,2-diphenylethane, 2,4-diaminodiphenylsulfone, 4,4’-diaminodiphenylsulfone, m-aminophenol, m-aminobenzylamine, benzyldimethylamine, 2-dimethylaminomethylphenol, triethanolamine, methylbenzylamine, α-(m-aminophenyl)ethylamine, α-(p-aminophenyl)ethylamine, diaminodiethyldimethyldiphenylmethane, α,α’-bis(4-aminophenyl)-p-diisopropylbenzene, etc.

Particular examples of the acid anhydride-based hardener may be dodecenyl succinic anhydride, polyadipic anhydride, polyazelaic anhydride, polysebacic anhydride, poly(ethyl octadecanedioic) anhydride, poly(phenylhexadecanedioic)anhydride, methyl tetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhimic anhydride, tetrahydrophthalic anhydride, trialkyl tetrahydrophthalic anhydride, methyl cyclohexene dicarboxylic anhydride, methyl cyclohexene tetracarboxylic anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, het anhydride, nadic anhydride, methyl nadic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic anhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, etc.

The epoxy resin compound includes 40 wt% to 97 wt% of the inorganic filler with respect to a total epoxy resin compound.

When the inorganic filler is included less than the foregoing range, the effects intended by the present invention such as high thermal conductivity, low thermal expansion behavior, and high heat resistance are not sufficiently exhibited. The larger the additive amount of the inorganic filler is, the better the effects are. However, the effects are not enhanced according to a volume fraction thereof but enhanced rapidly from a certain additive amount. Physical characteristics of the inorganic filler are due to the effect of a controlled higher-order structure in a polymer state and it may be understood that the certain amount of the inorganic filler is required because the higher-order structure is mainly obtained on a surface of the inorganic filler. Meanwhile, when the additive amount of the inorganic filler is more than the foregoing range, formability may deteriorate due to high viscosity.

A spherical inorganic filler may be used as the inorganic filler. Although the spherical inorganic filler is not particularly limited as long as it has a spherical shape including a parabolic cross-section, it is particularly desirable that the inorganic filler has a spherical shape as perfect as possible in terms of fluidity improvement.

The inorganic filler may be alumina, aluminum nitride, silicon nitride, boron nitride, or crystalline silica, and may be used by mixing two or more inorganic fillers different from each other. An average particle diameter of the inorganic filler may be 30 μm or less. The fluidity of the epoxy resin compound may deteriorate and the strength thereof may also decrease when the average particle diameter is larger than 30 μm.

A publicly-known hardening accelerator may be combined in the epoxy resin compound of the present invention. Examples of the hardening accelerator may be amines, imidazoles, organic phosphines, and a Lewis acid, and in particular, tertiary amines such as 1,8-diazabicyclo(5,4,0)undecene-7, triethylenediamine, bezyldimethylamine, triethanolamine, dimethylaminoethanol, or tris(dimethylaminomethyl)phenol, imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, or 2-heptadecylimidazole, organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine, or phenylphosphine, tetra-substituted phosphonium?tetra-substituted borate such as tetraphenylphosphonium?tetraphenylborate, tetraphenylphosphonium ?ethyltriphenylborate, or tetrabutylphosphonium?tetrabutylborate, tetraphenylborate such as 2-ethyl-4-methylimidazole?tetraphenylborate or N-methylmorpholine?tetraphenylborate, etc.

In the epoxy resin compound of the present invention, a wax may be used as a release agent generally used in an epoxy resin compound. Examples of the wax may be stearic acid, montanic acid, montanic acid ester, phosphoric acid ester, etc.

In the epoxy resin compound of the present invention, a coupling agent generally used in an epoxy resin compound may be used in order to improve the adhesion between the inorganic filler and the resin component. For example, epoxy silane may be used as a coupling agent.

When the epoxy resin compound of the present invention includes an epoxy resin, a hardener, and an inorganic filler as major components, the epoxy resin may be included in a range of 3 wt% to 60 wt% of a total weight, the inorganic filler may be included in a range of 40 wt% to 97 wt%, and the hardener may be included in a range of 0.5 wt% to 5 wt%.

Other components in addition to the epoxy resin, the hardener, and the coupling agent are dissolved in a solvent, for example, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), isopropyl alcohol (IPA), butanol, or toluene, and then stirred while heated. The inorganic filler was added thereto and uniformly mixed with a mixer or the like. Thereafter, the coupling agent is added and the epoxy resin compound is prepared through mixing and kneading by a heating roll or a kneader. The mixing sequence of the foregoing components is not particularly limited.

At this time, the solvent may be in a range of 10 wt% to 20 wt% with respect to the total weight of the epoxy resin compound.

The epoxy resin compound of the present invention may be applied to a radiant heat circuit board as shown in FIG. 1. Referring to FIG. 1, a radiant heat circuit board 100 of the present invention includes a metal plate 110, an insulation layer 120 formed on the metal plate 110, and a circuit pattern 130 formed on the insulation layer 120.

The metal plate 110 may be an alloy including copper, aluminum, nickel, gold, or platinum which have good thermal conductivity.

The metal plate 110 includes a metal protrusion 115 constituting a mounting pad mounting a heat dissipation device 150.

The metal protrusion 115 is extended from the metal plate 110 and protrudes vertically. A portion of an upper surface of the metal protrusion 115 functions as the mounting pad mounting the heat dissipation device 150 and has a predetermined width in order for a solder to be positioned on the upper surface of the metal protrusion 115.

The insulation layer 120 is formed while opening the integrated metal protrusion 115.

The insulation layer 120 may be formed of a plurality of insulation layers and insulates between the metal plate 110 and the circuit pattern 130 on the insulation layer 120.

The insulation layer 120 may be formed by curing the crystalline epoxy resin compound suggested in the present invention and an inorganic filler 125 is uniformly distributed in the insulation layer 120.

A plurality of the circuit patterns 130 is formed on the insulation layer 120.

The insulation layer 120 of the present invention is formed by using the crystalline epoxy resin compound, and thus conductivity is improved. Therefore, the insulation layer 120 may transfer the heat from the heat dissipation device 150 to the lower metal plate 110.

At this time, the heat dissipation device 150 may be a light-emitting diode and a light-emitting unit may be formed by arranging a plurality of the light-emitting diodes on one radiation heat circuit board 100.

The present invention is described in more detail according to the following Examples.

(Example 1)

10 wt% of bisphenol-A, 5 wt% of o-cresol-novolac, 5 wt% of the crystalline epoxy resin of Chemical Formula 1, an epoxy resin having 7 wt% of a multi-aromatic resin, 2.7 wt% of a TPP-K hardener, 0.3 wt% of an imidazole-based hardening accelerator, and 0.5 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Example 1 was obtained by adding 70 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

Thermal conductivity was measured through a transient hot wire method by using a LFA447 thermal conductivity instrument of NETZSCH GmbH.

The heat of fusion was measured at a heating rate of 10 °C/minute by using a differential scanning calorimeter (TA instruments product DSC Q100).

Glass transition temperature was also measured at a heating rate of 10 °C/minute by using a DSC Q100 differential scanning calorimeter of TA instruments.

(Example 2)

5 wt% of o-cresol-novolac, 5 wt% of the crystalline epoxy resin of Chemical Formula 1, an epoxy resin having 7 wt% of a multi-aromatic resin, 2.2 wt% of a TPP-K hardener, 0.2 wt% of an imidazole-based hardening accelerator, and 0.7 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Example 2 was obtained by adding 80 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Example 3)

2 wt% of bisphenol-A, 5 wt% of the crystalline epoxy resin of Chemical Formula 1, an epoxy resin having 2 wt% of a multi-aromatic resin, 0.9 wt% of an imidazole-based hardener, 0.1 wt% of an imidazole-based hardening accelerator, and 0.7 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Example 3 was obtained by adding 90 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Example 4)

2 wt% of bisphenol-A, 3 wt% of the crystalline epoxy resin of Chemical Formula 1, an epoxy resin having 2 wt% of a multi-aromatic resin, 0.9 wt% of an imidazole-based hardener, 0.1 wt% of an imidazole-based hardening accelerator, and 0.8 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Example 4 was obtained by adding 92 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Example 5)

1 wt% of bisphenol-A, 2 wt% of the crystalline epoxy resin of Chemical Formula 1, an epoxy resin having 1 wt% of a multi-aromatic resin, 0.9 wt% of an imidazole-based hardener, 0.1 wt% of an imidazole-based hardening accelerator, and 0.8 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Example 5 was obtained by adding 95 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Comparative Example 1)

14.5 wt% of bisphenol-A, 10 wt% of phenol novolac, 10 wt% of o-cresol-novolac, an epoxy resin having 10 wt% of a multi-aromatic resin, 4.5 wt% of a phenol-based hardener, 0.5 wt% of an imidazole-based hardening accelerator, and 0.5 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Comparative Example 1 was obtained by adding 50 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Comparative Example 2)

10 wt% of bisphenol-A, 8 wt% of phenol novolac, 8 wt% of o-cresol-novolac, an epoxy resin having 10 wt% of a multi-aromatic resin, 3.1 wt% of a phenol-based hardener, 0.4 wt% of an imidazole-based hardening accelerator, and 0.5 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Comparative Example 2 was obtained by adding 60 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

(Comparative Example 3)

3 wt% of bisphenol-A, 2 wt% of phenol novolac, 2 wt% of o-cresol-novolac, an epoxy resin having 2 wt% of a multi-aromatic resin, 0.9 wt% of an imidazole-based hardener, 0.1 wt% of an imidazole-based hardening accelerator, and a 0.7 wt% of a BYK-W980 additive were all mixed and stirred at 40°C for 10 minutes, and then a crystalline epoxy resin compound of Comparative Example 3 was obtained by adding 90 wt% of an alumina inorganic filler and stirring at room temperature for 20 minutes to 30 minutes.

Thermal Conductivity Measurement

Thermal conductivities of respective Examples and Comparative Examples were measured through a transient hot wire method by using a LFA447 thermal conductivity instrument of NETZSCH GmbH and the results thereof are presented in Table 1.

As shown in Table 1, it may be confirmed that Example 3 including the crystalline epoxy resin of Chemical Formula 1 has higher thermal conductivity when Example 3 and Comparative Example 3 including the same amounts of the inorganic filler were compared.

Heat of Fusion Measurement

Heat of fusion values were measured at a heating rate of 10 °C/minute by using a differential scanning calorimeter (TA instruments product DSC Q100) and the results thereof are presented in Table 1. It may be confirmed that the heat of fusion values of respective Examples and Comparative Examples belonged to similar categories. Also, it may be confirmed that the epoxy resin compounds of Examples have a thermal conductivity of 3 W/m?K or more when the inorganic filler was included 90 wt% or more.

Glass Transition Temperature

Glass transition temperatures were measured at a heating rate of 10 °C/minute by using a DSC Q100 differential scanning calorimeter of TA instruments and the results thereof are presented in Table 1. Since the glass transition temperatures of respective Examples and Comparative Examples were 100°C or more, it may be confirmed that other properties were not degraded even in the case of including the crystalline epoxy resin of Chemical Formula 1.

Table 1

Experiment No.	Thermal conductivity(W/mㆍK)	Glass transition temperature Tg(℃)	Heat of fusion (J/g)
Example 1	1.946	133.41	264.7
Example 2	1.970	146.54	229.2
Example 3	3.608	121.67	290.1
Example 4	5.357	123.87	313.2
Example 5	4.4955	122.23	249.9
Comparative Example 1	0.584	134.58	279.4
Comparative Example 2	1.009	133.74	251.4
Comparative Example 3	2.865	124.78	249.2

Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.

Claims

An epoxy resin compound comprising:

an epoxy resin;

a hardener; and

an inorganic filler,

wherein the epoxy resin comprises an epoxy resin of Chemical Formula below.

[Chemical Formula]

(where n is an integer between 0 and 50)
The epoxy resin compound according to claim 1, wherein the epoxy resin of Chemical Formula is included about 50 wt% or more with respect to a total weight of the epoxy resin compound.
The epoxy resin compound according to claim 1, wherein the inorganic filler is included in a range of about 40 wt% to about 97 wt% with respect to the total weight of the epoxy resin.
The epoxy resin compound according to claim 1, wherein the inorganic filler is at least one of alumina, boron nitride, aluminum nitride, crystalline silica, or silicon nitride.
The epoxy resin compound according to claim 1, wherein the epoxy resin is included in a range of about 3 wt% to about 60 wt% with respect to the total weight of the epoxy resin compound.
The epoxy resin compound according to claim 1, wherein the hardener is included in a range of about 0.5 wt% to about 5 wt% with respect to the total weight of the epoxy resin compound.
The epoxy resin compound according to claim 1, wherein the epoxy resin compound is used as an insulation material of a circuit board.
The epoxy resin compound according to claim 1, wherein the epoxy resin comprises a non-crystalline epoxy resin.
The epoxy resin compound according to claim 1, wherein the epoxy resin compound further comprises a hardening accelerator and a coupling agent.
The epoxy resin compound according to claim 1, wherein the epoxy resin compound has a thermal conductivity of about 3 W/m·K or more when the inorganic filler is included about 90 wt% or more.
A radiant heat circuit board comprising:

a metal plate;

an insulation layer formed on the metal plate; and

a circuit pattern formed on the insulation layer,

wherein the insulation layer is formed by curing an epoxy resin compound having an epoxy resin, a hardener, and an inorganic filler and the epoxy resin comprises an epoxy resin of Chemical Formula below.

[Chemical Formula]

(where n is an integer between 0 and 50)
The radiant heat circuit board according to claim 11, wherein the inorganic filler is included in a range of about 40 wt% to about 97 wt% with respect to a total weight of the epoxy resin compound.
The radiant heat circuit board according to claim 11, wherein the inorganic filler is at least one of alumina, boron nitride, aluminum nitride, crystalline silica, or silicon nitride.
The radiant heat circuit board according to claim 11, wherein the epoxy resin of Chemical Formula is a crystalline epoxy resin and is included about 12 wt% or more with respect to the total weight of the epoxy resin.
The radiant heat circuit board according to claim 11, wherein the radiant heat circuit board supports at least one heat dissipation device, and the heat dissipation device is a light-emitting diode.