JP2020196854A - Light-resistant attenuation epoxy resin and use of the same - Google Patents

Abstract

To provide an epoxy resin excellent in weather resistance and light resistance.SOLUTION: In an epoxy resin, a ratio (B/A) of aromatic proton (B) to aliphatic proton (A) measured by 1H nuclear magnetic resonance method (1H-NMR) is 0.15 to 0.29.SELECTED DRAWING: None

Description

The present invention relates to epoxy resins, and more particularly to light-damping epoxy resins having a ratio of aromatic protons to predetermined aliphatic protons. The epoxy resin according to the present invention can be used in the preparation of a packaging composition in order to provide a packaging material particularly applied to a light emitting diode (LED).

With the development of science and technology, photoelectric materials have been widely studied and applied to various fields. For example, LEDs are one of the main research subjects in photoelectric materials, and can be used for outdoor devices such as electronic signboards, indicator lamps, and detectors. However, since the LED packaging material in the above-mentioned outdoor device is exposed to the outdoor environment for a long time, there is a tendency that the light transmittance is attenuated due to the influence of climate (for example, temperature) and light irradiation. Therefore, the requirements for LED packaging materials in terms of weather resistance and light resistance as well as high light transmittance tend to be strict.

Currently, LED packaging materials mainly include epoxy resin and silicone, but silicone has a problem that its cost is high and the obtained packaging material is generally inferior in mechanical strength. Therefore, at present, epoxy resin is still the mainstream as a material for LED packaging. However, conventional epoxy resins have the problem of insufficient weather resistance and light resistance, and the resulting packaging material has a light transmittance when exposed to high temperatures for extended periods of time or exposed to ultraviolet light. Was significantly attenuated.

The present invention relates to a light-damping epoxy resin (also referred to herein as the "first epoxy resin"). Specifically, the present invention relates to a light-resistant epoxy resin having a ratio of aromatic protons to predetermined aliphatic protons. The present invention achieves a technical effect of improving the light resistance and heat resistance of the packaging material obtained from the epoxy resin by controlling the ratio of aromatic protons to aliphatic protons in the epoxy resin. The resulting packaging material also has suitable mechanical strength. Therefore, the epoxy resin according to the present invention is particularly suitable as a material for LED packaging.

Therefore, one object of the present invention was measured by ¹ H nuclear magnetic resonance ⁽¹ H-NMR), the proportion of the aromatic protons to aliphatic protons (A) (B) (B / A) is 0. It is to provide an epoxy resin which is 15 to 0.29.

In some embodiments of the present invention, the epoxy resin further has an epoxy equivalent of 500-2000 [g / eq] (weight per epoxy, WPE).

式（Ｉ）において、Ｒ₁は

であり、Ｒ₂はそれぞれ独立してＨ又はＣＨ₃であり、ｍは０〜２の整数であり、式中、^*は結合位置を表す。上記の２つのエポキシ基を有する芳香族エポキシ化合物は例えば、ビスフェノールＡジグリシジルエーテル（ｂｉｓｐｈｅｎｏｌ Ａ ｄｉｇｌｙｃｉｄｙｌ ｅｔｈｅｒ）、ビスフェノールＦジグリシジルエーテル（ｂｉｓｐｈｅｎｏｌ Ｆ ｄｉｇｌｙｃｉｄｙｌ ｅｔｈｅｒ）、及びその組み合わせからなる群から選択することができる。 In some embodiments of the invention, the epoxy resin is a structural unit derived from an alicyclic compound having two carboxyl groups, and an aromatic epoxy compound having two epoxy groups. Includes building blocks derived from epoxyide). More specifically, the alicyclic compound having the above two carboxyl groups may have the structure of the following formula (I).

In formula (I), R ₁ is

R ₂ is H or CH ₃ independently, m is an integer of 0 to 2, and ^* represents the coupling position in the equation. The aromatic epoxy compound having the above two epoxy groups can be selected from the group consisting of, for example, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and a combination thereof. it can.

式（ＩＩ）において、Ｘ₁〜Ｘ₈、Ｒ₁₁及びＲ₁₂はそれぞれ独立してＨ又はＣＨ₃である。上記の２つのエポキシ基を有する脂環族エポキシ化合物は例えば、

及びその組み合わせ（式中、ｎは１〜３０の整数である。）からなる群から選択することができる。 In some embodiments of the invention, the epoxy resin is a structural unit derived from an aromatic compound having two −OH groups, and an alicyclic epoxy compound having two epoxy groups (alicyclic epoxy compound). Includes building blocks derived from aromatic epoxides). More specifically, the above-mentioned aromatic compound having two −OH groups may have the structure of the following formula (II).

In formula (II), X _{1 to} X ₈ , R ₁₁ and R ₁₂ are independently H or CH ₃ , respectively. The alicyclic epoxy compound having the above two epoxy groups is, for example,

And combinations thereof (in the formula, n is an integer of 1 to 30) can be selected from the group.

Another object of the present invention is to provide the use of epoxy resins as described above for preparing packaging compositions.

Yet another object of the present invention is to provide a packaging composition containing a first epoxy resin and a curing agent, wherein the first epoxy resin is an epoxy resin as described above. The above curing agent can be selected from the group consisting of, for example, acid anhydrides, phenolic resins, imidazoles, and combinations thereof.

In some embodiments of the present invention, the above packaging composition further comprises a second epoxy resin selected from the group consisting of isocyanurate-based epoxy resins, alicyclic epoxy resins, and combinations thereof.

Yet another object of the present invention is to produce by curing the above-mentioned packaging composition, and the packaging material is fired at 150 ° C. for 168 hours and then has a light transmittance before firing. Rather than providing a packaging material whose light transmittance attenuation is less than 23%.

Hereinafter, in order to make it easier to understand the above-mentioned objectives, technical features and advantages according to the present invention more clearly, some specific embodiments will be described in detail.

Hereinafter, some specific embodiments according to the present invention will be described in detail, but the present invention can be carried out in a plurality of different modes as long as it does not deviate from the spirit, and the scope of protection of the present invention. Is not limited by the specific embodiments described above.

Unless otherwise stated, the terms "one", "corresponding" and similar terms used herein (in particular, the appended claims) should be understood to include singular and plural forms. is there.

In the present specification, the term "normal temperature and pressure" means an atmosphere having a temperature of 25 ° C. and a pressure of 1 atm.

As used herein, the term "light attenuation" means attenuation of light transmittance. The term "light-resistant attenuation" means that the material has less attenuation of light transmittance after being exposed to heat or light. In the present specification, the light transmittance means a value of the light transmittance measured by light irradiation at 400 nm.

Unless otherwise stated, the terms "first," "second," and similar terms used herein (in particular, the claims of the attachment) are merely to distinguish the elements or components described. It has no special meaning in itself and does not mean the order before and after.

The effect of the present invention as compared to the prior art provides an epoxy resin having a ratio of the number of aromatic protons to a predetermined aliphatic proton, which provides suitable mechanical strength and excellent light resistance and heat resistance. It is to provide a packaging material that also serves as a preparation. Hereinafter, the epoxy resin according to the present invention and its related applications will be described in detail.

1. 1. Epoxy resin (first epoxy resin)

In the present specification, the epoxy resin is a thermosetting resin having an epoxy functional group. The epoxy resin according to the present invention (that is, “first epoxy resin”) is the aromatic proton (B) relative to the aliphatic proton (A) measured by ¹ H nuclear magnetic resonance ( ¹ H-NMR). The ratio (B / A) is 0.15 to 0.29, for example 0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0 It is characterized by being .24, 0.25, 0.25, 0.27, or 0.28. Regarding light attenuation, the epoxy resin according to the present invention has an aromatic proton (B) ratio (B / A) to an aliphatic proton (A) measured by ¹ H nuclear magnetic resonance ( ¹ H-NMR). It is preferably 0.15 to 0.21. The epoxy resin according to the present invention further has an epoxy equivalent (WPE) of 500 to 2000 [g / eq], for example, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050. It may have 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500, 1550, 1600, 1650, 1700, 1750, 1800, 1850, 1900, or 1950 [g / eq].

As will be described later, the epoxy resin of the present invention may be prepared by reacting an alicyclic compound having two carboxyl groups with an aromatic epoxy compound having two epoxy groups, or two −OH groups. Since it may be prepared by reacting an aromatic compound having the above with an alicyclic epoxy compound having two epoxy groups.
The epoxy resin of the present invention contains, or is derived from, a structural unit derived from an alicyclic compound having two carboxyl groups and a structural unit derived from an aromatic epoxy compound having two epoxy groups. It may be constructed and may include or contain a structural unit derived from an aromatic compound having two −OH groups and a structural unit derived from an alicyclic epoxy compound having two epoxy groups. It may be composed of.

11.2 Alicyclic compounds with two carboxyl groups

As used herein, an alicyclic compound having two carboxyl groups is a compound having two carboxyl groups and at least one aliphatic ring in one molecule. The number of carbon atoms in the aliphatic ring is at least 3, preferably 3 to 16, more preferably 3 to 8, and may be saturated or unsaturated, but preferably saturated. Further, the aliphatic ring may be substituted or unsubstituted, and the aliphatic ring may contain a heteroatom such as oxygen or sulfur.

In a preferred embodiment of the present invention, the alicyclic compound having two carboxyl groups has the structure of the following formula (I).

であり、Ｒ₂はそれぞれ独立してＨ又はＣＨ₃であり、ｍは０〜２の整数であり、式中、^*は結合位置を表す。 In formula (I), R ₁ is

R ₂ is H or CH ₃ independently, m is an integer of 0 to 2, and ^* represents the coupling position in the equation.

The compound having the structure of the formula (I) may be prepared by reacting an alicyclic acid anhydride with an alicyclic diol. Examples of alicyclic acid anhydrides include hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, dimethylhexahydrophthalic anhydride, tetrahydrophthalic anhydride, and methyltetrahydrophthalic anhydride. , And dimethyltetrahydrophthalic anhydride, but not limited to. Examples of alicyclic diols include 1,4-cyclohexanedimethanol, tricyclo [5.2.1.0 ^2,6 ] decanedimethanol (triciclo [5.2.1.0 ^2,6 ] decanedimethanol), and so on. 2,2-bis (4-hydroxycyclohexyl) propane (hydrogenated bisphenol A), bis (4-hydroxycyclohexyl) methane (hydrogenated bisphenol F), 4,4'-bis (hydroxymethyl) bicyclohexane , 3,9-bis (1,1-dimethyl-2-hydroxyethyl) -2,4,8,10-tetraoxaspiro [5.5] undecane (spiroglycol), and 5-ethyl-2- (2) Includes, but is not limited to, -hydroxy-1,1-dimethylethyl) -5-hydroxymethyl-1,3-dioxane. In the examples described later, when preparing the compound having the structure of the formula (I), hexahydrophthalic anhydride and methylhexahydrophthalic anhydride were used as the alicyclic acid anhydride, and the alicyclic diol was used. These include 1,4-cyclohexanedimethanol, tricyclo [5.2.1.0 ^2,6 ] decanedimethanol (triciclo [5.2.1.0 ^2,6 ] decanedimethanol), 2,2-bis (4). -Hydroxycyclohexyl) propane (hydrogenated bisphenol A) is used.

1.2.2 Aromatic epoxy compounds with two epoxy groups

As used herein, an aromatic epoxy compound having two epoxy groups is an epoxy compound having two epoxy groups and at least one aromatic ring in one molecule. The number of carbon atoms in the aromatic ring is at least 4, preferably 6 to 24, and even more preferably 6 to 18. The aromatic ring may be substituted or unsubstituted, and the aromatic ring may contain heteroatoms such as oxygen, sulfur, and nitrogen.

In some embodiments of the present invention, the aromatic epoxy compound having two epoxy groups is a diglycidyl ether of a bifunctional phenol compound, and examples of the bifunctional phenol compound include bisphenol A (bisphenol A). , BPA), tetramethylbisphenol A, dimethylbisphenol A, bisphenol F, tetramethylbisphenol F, dimethylbisphenol F, bisphenol S, tetramethylbisphenol S, dimethylbisphenol S, 4,4'-biphenol, tetramethyl-4,4 '-Biphenol, dimethyl-4,4'-biphenol, 1- (4-hydroxyphenyl) -2- [4- (1,1-bis- (4-hydroxyphenyl) ethyl) phenyl] propane, 2,2' -Methylene-bis (4-methyl-6-t-butylphenol), resorcinol, hydroquinone, 9,9-bis (4-hydroxyphenyl) -9H-fluorene, and 9,9-bis (4-hydroxy-3-methyl) Contains, but is not limited to, phenyl) -9H-fluorene.

In a preferred embodiment of the present invention, the aromatic epoxy compound having two epoxy groups is selected from the group consisting of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and combinations thereof.

1. 3. Aromatic compounds with two -OH groups

As used herein, an aromatic compound having two -OH groups is a compound having two -OH groups and at least one aromatic ring in one molecule. In some embodiments of the present invention, the aromatic compound having two −OH groups has the structure of the following formula (II).

In formula (II), X _{1 to} X ₈ , R ₁₁ and R ₁₂ are independently H or CH ₃ , respectively. In a preferred embodiment of the present invention, X _{1 to} X ₈ are all H, and R ₁₁ and R ₁₂ are both CH ₃ . In the examples described later, the aromatic compound having two −OH groups is bisphenol A (that is, in formula (II), X _{1 to} X ₈ are all H, and R ₁₁ and R ₁₂ are any. Is also CH _3. ) Is used.

1.4.4 Alicyclic epoxy compounds with two epoxy groups

As used herein, an alicyclic epoxy compound having two epoxy groups is an epoxy compound having two epoxy groups and at least one aliphatic ring in one molecule. The alicyclic epoxy compound having two epoxy groups may be the diglycidyl ether of the alicyclic diol described above, but the present invention is not limited thereto. Specifically, examples of the alicyclic epoxy compound having two epoxy groups include a dicyclopentadiene-based epoxy resin and a hydride bisphenol A-type epoxy resin. ), And 7-oxadicyclo [4.1.0] heptane-type epoxy resin (7-oxabiciclo [4.1.0] heptane-based epoxy resin), but is not limited thereto.

In some embodiments of the present invention, one or more of the 7-oxadicyclo [4.1.0] heptane-type epoxy resins having the structure of the following formula (III) are used.

であり、式中、ｎは１〜３０の整数であり、^*は結合位置を表す。 In formula (III), R ₂₁ is H or CH ₃ , Y is a covalent bond, -CH (CH ₃ )-, -CH ₂ CH _2- , -CH ₂ CH (CH ₃ )-, -CH ₂ CH. ₂ CH ₂ −, −C (= O) OCH ₂ −, −OC (= O) (CH ₂ ) ₄ C (= O) O−, −CH ₂ OC (= O) (CH ₂ ) ₄ C (= O) OCH _2- ,

In the equation, n is an integer of 1 to 30, and ^* represents the connection position.

からなる群（式中、ｎは１〜３０の整数である。）を含むが、これに制限されない。 As a specific example of the 7-oxadicyclo [4.1.0] heptane type epoxy resin having the structure of the formula (III),

It includes, but is not limited to, a group consisting of (in the equation, n is an integer of 1 to 30).

1.5. Preparation and properties of epoxy resin

The epoxy resin having a predetermined B / A value according to the present invention has an alicyclic or aromatic compound having two −OH groups and an aromatic or alicyclic having at least two epoxy groups in the presence of a catalyst. An epoxy resin having a desired B / A value can be prepared by reacting with a group epoxy compound and adjusting the ratio of these components. The type of the above-mentioned catalyst is not particularly limited as long as it can promote ring-opening of the epoxy functional group and reduce the reaction temperature. Suitable catalysts include, but are not limited to, amines, imidazoles, and phosphorus-containing compounds. Examples of amines include 1,8-diazabicyclo [5.4.0] undec-7-ene (1,8-diazabicyclo [5.4.0] undec-7-ene), triethylenediamine, and 2, Includes, but is not limited to, 4,6-tri (dimethylaminomethyl) phenol (2,4,6-tris (dimethylaminomethyl) phenol). Examples of imidazoles include, but are not limited to, 2-ethyl-4-methylimidazole and 2-methylimidazole. Examples of phosphorus-containing compounds include triphenyl-n-butylphosphonium bromide (TBP), triphenylphosphine (triphenylphosphine), tetraphenylphosphonium-tetraphenylborate (tetraphenylphosphine), and tetraphenylphosphine. Includes, but is not limited to, -n-butylphosphonium-o, o-diethylphosphologiate (tetra-n-butylphosphoneium-o, o-diethyl phosphonethioate). Each of the above catalysts may be used alone or in combination of two or more.

In a preferred embodiment of the present invention, the epoxy resin is obtained by reacting an alicyclic compound having two carboxyl groups with an aromatic epoxy compound having two epoxy groups. First, an alicyclic diol and an alicyclic acid anhydride are mixed and heated to 90 ° C to 110 ° C, and then an exothermic reaction is carried out to reach a temperature of 160 ° C to 180 ° C. After the exothermic reaction is completed, the temperature is increased. Is lowered to 140 ° C. to 150 ° C. and maintained at the same temperature for 2 hours to prepare an alicyclic compound (intermediate product) having two carboxyl groups. The intermediate product is then lowered to 100 ° C. to 120 ° C., an aromatic epoxy compound with two epoxy groups is added, mixed uniformly and then the catalyst is added. Then, after heating to 150 ° C. to 160 ° C., an exothermic reaction is carried out to reach a temperature of 180 ° C. to 200 ° C., and after the exothermic reaction is completed, the temperature is lowered to 150 ° C. to 170 ° C. at the same temperature. The epoxy resin according to the present invention is prepared by maintaining the time. Here, an alicyclic group having two carboxyl groups so that the ratio (B / A) of the number of aromatic protons (B) to the aliphatic proton (A) of the prepared epoxy resin is 0.21 or less. It is preferable to control the amount of the compound and the aromatic epoxy compound having two epoxy groups. As shown in Examples described later, in this case, the best light attenuation property (heat light attenuation value of less than 15%, UV light attenuation value of less than 3%) can be provided.

In another embodiment of the present invention, the epoxy resin is obtained by reacting an aromatic compound having two −OH groups with an alicyclic epoxy compound having two epoxy groups. First, the alicyclic epoxy compound having two epoxy groups is heated to 80 ° C. to 100 ° C., then the aromatic compound having two −OH groups is added, mixed uniformly, and then the catalyst is added. After that, it is heated to 130 ° C. to 150 ° C., an exothermic reaction is carried out to reach a temperature of 180 ° C. to 200 ° C., and after the exothermic reaction is completed, the temperature is reduced to 150 ° C. to 170 ° C. maintain. Then, the epoxy resin according to the present invention can be obtained by adding the alicyclic epoxy compound having two epoxy groups again and maintaining the reaction at 150 ° C. to 170 ° C. for 2 hours to carry out the reaction.

The epoxy resin according to the present invention has the ratio (B / A) of the number of aromatic protons (B) to the aliphatic proton (A) measured by ¹ H-NMR and the epoxy equivalent value, as well as 60 ° C. ~ 115 ° C, for example, 65 ° C, 68 ° C, 70 ° C, 75 ° C, 80 ° C, 81 ° C, 85 ° C, 89 ° C, 90 ° C, 92 ° C, 96 ° C, 100 ° C, 105 ° C, 108 ° C, It preferably has a softening point of 110 ° C. or 113 ° C. The epoxy resin according to the present invention is preferably an epoxy resin that is liquid at normal temperature and pressure. Specifically, the epoxy resin according to the present invention has a viscosity lower than 1000 Pa · s at normal temperature and pressure. Is preferable.

2. 2. Composition for packaging

The epoxy resin according to the present invention can be used for preparing a composition for packaging. Therefore, the present invention also contains necessary components such as a first epoxy resin and a curing agent, and also contains other components selected and used as needed, and the first epoxy resin is a predetermined one as described above. Provided is a packaging composition which is an epoxy resin having a B / A value of.

In the packaging composition according to the present invention, the content of the first epoxy resin is 45% by weight to 65% by weight, for example 47% by weight, 50% by weight, 52% by weight, based on the total weight of the packaging composition. %, 54% by weight, 55% by weight, 56% by weight, 57% by weight, 58% by weight, 59% by weight, 60% by weight, or 63% by weight.

2.1. Hardener

As used herein, the curing agent means a component that initiates a ring-opening reaction of an epoxy functional group to carry out a cross-linking curing reaction with an epoxy resin. The type of the curing agent is not particularly limited, and the ring-opening reaction of the epoxy functional group may be started to carry out the cross-linking curing reaction with the epoxy resin. Examples of curing agents include, but are not limited to, acid anhydrides, phenolic resins, and imidazoles. Each of the above curing agents may be used alone or in combination of two or more.

Acid anhydrides include monovalent carboxylic acid anhydrides, acid dianhydrides, polyvalent carboxylic acid anhydrides, and copolymers of the above acid anhydrides with other polymerizable monomers. Not limited to this. Examples of monovalent carboxylic acid anhydrides include, but are not limited to, acetic acid anhydride, maleic anhydride, succinic anhydride, hexahydrophthalic anhydride, or 4-methylhexahydrophthalic anhydride. .. Examples of acid dianhydrides include, but are not limited to, naphthalene tetracarboxylic dianhydride or pyromellitic dianhydride. Examples of polyvalent carboxylic acid anhydrides include, but are not limited to, mellitic trianhydride. Examples of copolymers of acid anhydrides with other polymerizable monomers include, but are not limited to, styrene-maleic anhydride copolymers (copolymer of styrene and maleic anhydride).

Examples of phenolic resins include, but are not limited to, novolac phenolic resin and resol phenolic resin. Examples of novolak-type phenolic resins include, but are not limited to, phenol novolac resin, phenol aralkyl resin, cresol novolak resin, t-butylphenol novolak resin, and nonylphenol novolak resin.

Examples of imidazoles include, but are not limited to, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 1-benzyl-2-phenylimidazole.

In a preferred embodiment of the present invention, the curing agent is a curing agent that is liquid at normal temperature and pressure, and specifically, a curing agent having a viscosity at normal temperature and pressure lower than 1000 Pa · s. In the examples described later, an acid anhydride which is a liquid at normal temperature and pressure is used as a curing agent.

In the packaging composition according to the present invention, the content of the curing agent is not particularly limited, and a desired curing effect may be provided. Generally, the content of the curing agent is 20% to 35% by weight, for example 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, based on the total weight of the composition for packaging. It can be% by weight, 28% by weight, 30% by weight, or 33% by weight.

2.2. Second epoxy resin

The packaging composition according to the present invention contributes to curing of the packaging composition by further containing a second epoxy resin as a curing aid (auxiliary hardener) in addition to the first epoxy resin, if necessary. It is possible. The second epoxy resin is a conventionally used epoxy resin, for example, an epoxy resin having a triazine ring, an alicyclic epoxy resin, a phenol-based epoxy resin (phenyl epoxy resin), a cresol-based epoxy resin (cresol epoxy resin), or a naphthalene-based epoxy resin. It may be, but is not limited to, an epoxy resin (naphthaleene epoxy resin) and a bisphenol epoxy resin (bisphenyl epoxy resin). Examples of epoxy resins having a triazine ring include, but are not limited to, isocyanurate-based epoxy resins, such as triglycidyl isocyanurate. Examples of alicyclic epoxy resins include the above alicyclic epoxy compounds, such as (3', 4'-epoxycyclohexane) methyl-3,4-epoxycyclohexylcarboxylate ((3', 4'-). Epoxycyclohexane) methyl 3,4-epoxycyclohexyl carboxylate), but is not limited thereto. Examples of cresol-based epoxy resins include o-cresol-based epoxy resins (ortho-cresol epoxy resin), m-cresol-based epoxy resins (meta-cresol epoxy resin), and p-cresol epoxy resins (para-cresol epoxy resin). ), But is not limited to this. Examples of the bisphenol-based epoxy resin include, but are not limited to, a bisphenol A type epoxy resin and a bisphenol F type epoxy resin (bisphenol F epoxy resin). Each of the above epoxy resins may be used alone or in combination of two or more. In the examples described later, as the second epoxy resin, triglycidyl isocyanurate or (3', 4'-epoxycyclohexane) methyl-3,4-epoxycyclohexylcarboxylate is used.

In a preferred embodiment of the present invention, the second epoxy resin is an epoxy resin that is liquid at normal temperature and pressure, and specifically, an epoxy resin having a viscosity lower than 1000 Pa · s at normal temperature and pressure, or It is an epoxy resin that is liquid at least at the preparation temperature of the packaging composition. For example, in the examples described below, the packaging composition is prepared at a temperature of 120 ° C., where the second epoxy resin has a melting point lower than 120 ° C. so that it presents a liquid during the preparation process. Is preferable.

In the packaging composition according to the present invention, the content of the second epoxy resin is not particularly limited, providing a desired auxiliary effect, and adversely affecting the light attenuation property and mechanical strength of the prepared packaging material. Should not be given. Generally, the content of the second epoxy resin is 10% to 20% by weight, for example 11% by weight, 12% by weight, 13% by weight, 14% by weight, based on the total weight of the composition for packaging. %, 15% by weight, 16% by weight, 17% by weight, 18% by weight, or 19% by weight.

2.3. Ingredients selected and used as needed

In the packaging composition according to the present invention, if necessary, the processability in the manufacturing process of the packaging composition is appropriately improved, or the physical properties of the cured material of the packaging composition are improved. , Other components selected and utilized, such as the catalysts described below and additives known in the art. Examples of additives known in the art are inorganic fillers, flame retardants, carbon blacks, colorants, defoamers, dispersants, viscosity modifiers, thixotropic agents, leveling agents. , Coupling agents, mold release agents, fungicides, stabilizers, antioxidants, and antibacterial agents, but are not limited thereto. Each additive may be used alone or in any combination.

In some embodiments of the present invention, a catalyst may be further added to the packaging composition so as to promote the epoxy functional group reaction and reduce the curing reaction temperature of the packaging composition. The type of catalyst is not particularly limited as long as it can promote ring-opening of the epoxy functional group and reduce the curing reaction temperature. Suitable catalysts include, but are not limited to, amines, imidazoles, phosphorus-containing compounds, and derivatives thereof. Each of the above catalysts may be used alone or in any combination. In the examples described below, triphenyl-n-butylphosphonium bromide (TBP) is used.

2.4. Preparation of packaging composition

To prepare the packaging composition according to the present invention, each component of the packaging composition is uniformly mixed and dissolved with a stirrer, or dispersed in a solvent to prepare a varnish, which can be used in later processing. Served. The above solvent can dissolve or disperse each component of the packaging composition, but does not react with any of these components, such as toluene, γ-butylolactum, methylethylketone, cyclohexanone, butanone, acetone, ditoluene, methylisobutyl. Ketone, N, N-dimethylformamide (N, N-dimethylformamide, DMF), N, N-dimethylacetamide (N, N-dimethylacetamide, DMAc), and N-methylpyrrolidone (NMP). Can be.

However, the solvent volatilizes during heat curing, and the material for which the packaging composition has been cured is liable to have scratches such as bubbles and voids, which is disadvantageous for the use of the packaging material. Therefore, in order to prevent the solvent from volatilizing during heat curing and forming bubbles or voids in the cured product, it is common to not use the solvent when preparing the packaging composition, thereby packaging. It is suitably used as a material for materials, and can meet the environmental requirement of low VOC (volatile organic compound). In view of this, a solvent-free packaging composition according to the present invention can be prepared as follows. First, the first epoxy resin and the second epoxy resin are placed in a glass distillation flask and uniformly mixed at 110 ° C. to 130 ° C. for 30 minutes. Then, after the temperature is lowered to 90 ° C. to 110 ° C., a curing agent and a catalyst are added, and the mixture is uniformly mixed at the same temperature for 30 minutes to obtain a composition for packaging in a semi-cured state (B stage, B-stage). Can be done.

3. 3. Packaging material

The present invention also provides the packaging material given by the packaging composition described above and is formed by curing the packaging composition as described above, i.e., the packaging composition is completely cured (C). It is a material (also called a stage or C-stage). The means for curing the composition for packaging is not particularly limited, and in some embodiments of the present invention, the composition for packaging is cured by means of heating and pressurizing.

The packaging material according to the present invention can be applied to a package of a photoelectric element, and examples of the above-mentioned photoelectric element include, but are not limited to, an LED, a laser diode, and a photodetector. However, the packaging material according to the present invention is not limited to the above packaging applications, and can be applied to any packaging of articles requiring surface protection, such as packaging of wind power generator blades.

The packaging material according to the present invention has excellent light attenuation resistance. Specifically, the packaging material according to the present invention is fired at 150 ° C. for 168 hours, and then its light transmittance is higher than that before firing. The attenuation value of the transmittance is less than 23%, for example, 22%, 21%, 20%, 19%, 18%, 16%, 14%, 12%, 11%, 10%, 9%, 8%, 7%, 5%, or 3%, especially less than 15% in some embodiments. When the packaging material according to the present invention is continuously irradiated with a UV light source having a wavelength of 365 nm at 200 mW / cm ² for 336 hours, the attenuation value of the light transmittance is less than 5% than the light transmittance before irradiation. Yes, for example, 4.5%, 4%, 3.5%, 3%, 2.5%, 2%, 1.5%, 1%, or 0.5%, and in some embodiments. Is particularly less than 3%.

In addition, the packaging material according to the present invention has sufficient bending strength (flexural strength, FS) and flexural modulus (flexural modulus, FM). Specifically, the bending strength of the packaging material according to the present invention is 8 kgf / mm ^{2 to} 12 kgf / mm ² , for example, 8.5 kgf / mm ² , 9 kgf / mm ² , 9.5 kgf / mm ² , 10 kgf. / mm ^2, can be achieved ^{10.5kgf / mm 2, 11kgf / mm} 2, or the 11.5kgf / mm ^2. The flexural modulus of the packaging material according to the present ^{invention, 230kgf / mm 2 ~300kgf / mm} 2, for ^{example, 235kgf / mm 2, 240kgf /} mm 2, 245kgf / mm 2, 250kgf / mm 2, 255kgf / mm ² , 260 kgf / mm ² , 265 kgf / mm ² , 270 kgf / mm ² , 275 kgf / mm ² , 280 kgf / mm ² , 285 kgf / mm ² , 290 kgf / mm ² , or 295 kgf / mm ² can be achieved. For the packaging material according to the present invention, the flexural modulus can be regarded as an elastic modulus (EM), and the elastic modulus is proportional to the internal stress. Therefore, the lower the flexural modulus of the material, the lower the internal stress thereof, and the material having a low internal stress is less likely to crack due to a drastic change in temperature.

4. Example

4.1. Explanation of measuring means

Hereinafter, the present invention will be described exemplarily with reference to specific embodiments, and the measuring instruments and methods adopted are as follows.

[Measurement of by ¹ H nuclear magnetic resonance ⁽¹ H-NMR)]

The nuclear magnetic resonance hydrogen spectrum ( ¹ H-NMR) of the epoxy resin was measured by a nuclear magnetic resonance spectrometer (model: Unity 400, purchased from Varian). In the epoxy resin according to the present invention, the peak between 0.5 ppm and 5.5 ppm (that is, the A region) represents an aliphatic proton, and the peak between 6.5 ppm and 7.5 ppm (that is, the B region) is. Represents an aromatic proton. The aliphatic proton (A) is obtained by calculating the sum of the integral values of all the peaks in the A region, and the number of aromatic protons (B) is calculated by calculating the sum of the integral values of all the peaks in the B region. Obtained by

[Epoxy equivalent (WPE) measurement]

式中、Ｗはサンプル重量、ＶはＨＢｒの滴定体積、ＮはＨＢｒの濃度である。 0.15 g to 0.17 g of epoxy resin was placed in a beaker as a sample, and an indicator (eg, crystal violet) was added together with 55 ml of the corresponding solvent (eg, methyl ethyl ketone or toluene). A 0.1 N HBr-glacial acetic acid solution was used as a titration solution and titrated by a potentiometric titration method. Titration was performed with the inflection point in the potential change graph as the end point, and calculation was performed according to the following formula to obtain WPE.

In the formula, W is the sample weight, V is the titration volume of HBr, and N is the concentration of HBr.

[Measurement of softening point]

The ring and ball method was adopted as a method for measuring the softening point, and the measurement was performed as follows according to the measurement standard according to JIS K7322. First, 2.02 g of epoxy resin was placed in a preheated copper ring as a sample and melted at a temperature of an estimated softening point of + 70 ° C. to remove air bubbles. Then, the copper ring containing the sample was cooled at room temperature for at least 30 minutes. After that, a beaker containing glycerin was prepared and placed on a heater, a copper ring containing a sample was set on glycerin so as to hang it, an iron ball was placed on the sample, and an infrared detector was installed. Heating was started at a heating rate of 5 ° C./min of the heater, and it was confirmed by an infrared detector that the iron ball had fallen, and the temperature at which the iron ball had fallen was set as the softening point.

[Preparation of cured product sample]

A tablet-like product was produced from 46 ± 2 g of the packaging composition (B stage). The molding temperature of the molding machine (model: ST-75, purchased from a high-tech company) was set to 150 ± 2 ° C. After preheating the tablet to 80 ± 2 ° C., it was put into the feed port of the molding machine. Then, the obtained sample was cured in a mold for 4 minutes by punching and holding for 1 minute, and then the obtained sample (molded specimen) was taken out. If necessary, the molded sample can be post-cured at 150 ° C. for 4 hours to obtain a post-cured sample.

[Measurement of glass transition temperature (Tg)]

4 to 6 mg of the post-cured sample was collected on a surface plate. The Tg of the sample was measured with a differential scanning calorimetry (DSC) (model: DSC 2910, purchased from TA Instruments). The measurement conditions were a temperature parameter of 50 ° C. to 250 ° C. and a heating rate of 20 ° C./min. An inflection point was searched for in the obtained graph of heat flow, and the temperature on the temperature axis corresponding to the inflection point was defined as Tg.

[Thermal light attenuation measurement]

The molded sample was cut into a sample having a length of 60 mm, a width of 14 mm, and a thickness of 1 mm. The sample was set in a UV-Vis spectrometer (model: UV-1700, purchased from Shimadzu), and the light transmittance value in the 400 nm wavelength range (hereinafter, "initial light transmittance value"). ) Was measured. Then, the sample was placed in an oven and calcined continuously at 150 ± 2 ° C. for 168 hours. After taking out the sample and cooling it to room temperature, it was set again in a UV-visible spectroscope and the light transmittance value in the 400 nm wavelength range (hereinafter, “heat-resistant light transmittance value”) was measured. The value obtained by subtracting the initial light transmittance value from the heat-resistant light transmittance value was defined as the thermal light attenuation value.

[Ultraviolet (UV) light attenuation measurement]

The molded sample was cut into a sample having a length of 60 mm, a width of 14 mm, and a thickness of 1 mm. The sample was set in a UV-visible spectroscope, and the light transmittance value in the 400 nm wavelength region (hereinafter, “initial light transmittance value”) was measured. Then, the sample was placed at a distance of 5 cm under a UV light source having an intensity of 200 mW / cm ² and a wavelength of 365 nm, and was continuously irradiated with UV light for 336 hours. Then, the sample was set in the UV-visible spectroscope again, and the light transmittance value in the 400 nm wavelength region (hereinafter, “UV light transmittance value”) was measured. The value obtained by subtracting the initial light transmittance value from the UV light transmittance value was defined as the UV light attenuation value.

[Measurement of flexural strength and flexural modulus]

The bending strength and flexural modulus were measured as follows according to the measurement standard by JIS K6911. First, a post-cured sample having a length of 80 mm or more, a width of 10 ± 0.2 mm, and a thickness of 4 ± 0.2 mm was cut. Then, the sample was subjected to a three-point bending test using a universal material testing machine. The distance between the lower two support points was 64 mm, and the moving speed of the upper jig was 2 mm / min. When the sample burst, the bending strength and flexural modulus were measured. The unit of flexural strength is kgf / mm ² . The unit of flexural modulus is kgf / mm ² .

4.2. Material information list for examples and comparative examples

4.3. Preparation and property measurement of epoxy resin

The epoxy resins of Synthesis Examples 1 to 9 and Comparative Synthesis Examples 1 to 3 were prepared at the ratios shown in Tables 2-1 to 2-3 as follows.

In Synthesis Examples 1 to 8 and Comparative Synthesis Examples 1 to 3, first, an alicyclic diol and an alicyclic acid anhydride are mixed, heated to 100 ° C., and then subjected to an exothermic reaction to reach a temperature of 170 ° C. After the reaction was completed, the temperature was lowered to 145 ° C. and maintained at the same temperature for 2 hours to prepare an alicyclic compound (intermediate product) having two carboxyl groups. Then, the intermediate product was lowered to 110 ° C., diglycidyl ether of a bifunctional phenol compound was added, and the mixture was uniformly mixed before adding a catalyst. Then, after heating to 155 ° C., an exothermic reaction is carried out to reach a temperature of 190 ° C., and after the exothermic reaction is completed, the temperature is lowered to 160 ° C. and maintained at the same temperature for 2 hours. Epoxy resins of 8 and Comparative Synthesis Examples 2 and 3 are obtained, and the epoxy resin is not successfully synthesized in Comparative Synthesis Example 1.

In Synthesis Example 9, 100 parts by weight of the alicyclic epoxy compound was first heated to 90 ° C., then 53.8 parts by weight of the bifunctional phenol compound was added, and the mixture was uniformly mixed, and then 0.1 part by weight of the catalyst was added. .. Then, it was heated to 140 ° C., an exothermic reaction was carried out to reach a temperature of 190 ° C., and after the exothermic reaction was completed, the temperature was lowered to 160 ° C. and maintained at the same temperature for 2 hours. Then, 7.6 parts by weight of the alicyclic epoxy compound was added, and the reaction was carried out at 160 ° C. for 2 hours to obtain the epoxy resin of Synthesis Example 9.

Separately, commercially available epoxy resins 1 and 2 were prepared. The commercially available epoxy resin 1 is BE504H, and the commercially available epoxy resin 2 is BE503L.

The B / A values, softening points and WPE of the epoxy resins of Synthesis Examples 1 to 9, the epoxy resins of Comparative Synthesis Examples 1 to 3 and the commercially available epoxy resins 1 and 2 were measured by the measurement methods described above, and the results were obtained. Was recorded in Tables 2-1 to 2-3.

4.4. Preparation and property measurement of packaging composition (1)

The packaging compositions of Examples 1 to 9 and Comparative Examples 1 to 6 were prepared at the ratios shown in Tables 3-1 to 3-3. First, the first epoxy resin and the second epoxy resin were placed in a glass distillation flask and mixed uniformly at 120 ° C. for 30 minutes. Subsequently, the temperature was lowered to 100 ° C., the curing agent and the catalyst were added, and the mixture was uniformly mixed at the same temperature for 30 minutes to obtain a composition for each package (B stage).

The Tg, thermogravimetric attenuation value, UV light attenuation value, bending strength and flexural modulus of the cured package composition of Examples 1 to 9 and Comparative Examples 1 to 6 were measured by the measurement methods described above. , Tables 4-1 to 4-3.

As shown in Tables 4-1 and 4-2, the cured product formed from the package composition containing the epoxy resin having a predetermined B / A value according to the present invention has a relatively low thermal light attenuation value, comparison. It has a low UV light attenuation value, suitable Tg, sufficient bending strength and flexural modulus. In other words, the packaging material produced from the resin composition according to the present invention has particularly excellent light damping properties while maintaining sufficient mechanical strength. As can be seen from Examples 1 to 3, 7 and 8, even if the ratio of each component for preparing the epoxy resin is different, if the B / A value of the epoxy resin is within the specified range, it is produced. All of the packaging materials can obtain excellent light damping properties and sufficient mechanical strength. As can be seen from Examples 4 to 6 and 9, even if each component for preparing the epoxy resin is different, if the B / A value of the epoxy resin is within the specified range, the manufactured packaging material is In each case, excellent light attenuation properties and sufficient mechanical strength can be obtained. As can be seen from the results of Examples 1 to 7, the epoxy resin according to the present invention has a structural unit derived from an alicyclic compound having the structure of the formula (I), and an aromatic having two epoxy groups. When the ratio (B / A) of the number of aromatic protons (B) to the aliphatic proton (A) is 0.21 or less, which contains a structural unit derived from an epoxy compound, the best light attenuation property (15) is obtained. A thermal light attenuation value of less than%, or a UV light attenuation value of less than 3%) can be given.

On the other hand, as shown in Table 4-3, the cured product formed from the package composition containing no epoxy resin having a predetermined B / A value according to the present invention has a relatively low thermal light attenuation value. , Relatively low UV light attenuation value, suitable Tg, good bending strength and flexural modulus may be provided at the same time. In particular, as can be seen from Comparative Examples 1 to 6, unless the B / A value of the epoxy resin is within the specified range, the thermal light attenuation value and the UV light attenuation value of the manufactured packaging material are significantly increased. This indicates that the packaging material is inferior in light resistance and does not have the characteristics of light attenuation.

4.5. Preparation and property measurement of packaging composition (2)

The packaging compositions of Examples 10 to 11 and Comparative Example 7 were prepared at the ratios shown in Table 5. First, the first epoxy resin and solvent were placed in a glass distillation flask and mixed uniformly at 120 ° C. for 30 minutes. Then, after the temperature was lowered to 100 ° C., a curing agent and a catalyst were added, and the mixture was uniformly mixed at the same temperature for 30 minutes to obtain a composition (B stage) for each package. After the packaging composition was applied to a glass plate to form a film, it was fired at 100 ° C. for 2 hours to remove the solvent, and then fired at 150 ° C. for 4 hours to be post-cured, 60 mm long, 14 mm wide. It was cut into a sample having a thickness of 100 μm. Then, the thermal light attenuation values of the package compositions of Examples 10 to 11 and Comparative Example 7 were measured by the measurement method described above and recorded in Table 5.

As shown in Table 5, the packaging composition according to the present invention was formed as long as it contained an epoxy resin having a predetermined B / A value according to the present invention, even if it did not contain the second epoxy resin. The cured product can also have excellent light damping properties.

The above-mentioned examples are merely for exemplifying the principle of the present invention and its effects and describing the technical features of the present invention, and the scope of protection of the present invention is not limited thereto. Any changes or arrangements that can be easily completed by any person skilled in the art as long as they do not deviate from the technical principles and spirit of the present invention belong to the scope claimed in the present invention. Therefore, the scope of protection of the rights of the present invention is shown in the claims of the attached sheet.

Claims (14)

The ratio (B / A) of the aromatic proton (B) to the aliphatic proton (A) measured by ¹ H nuclear magnetic resonance ( ¹ H-NMR) is 0.15 to 0.29. Epoxy resin. The epoxy resin according to claim 1, further comprising an epoxy equivalent of 500 to 2000 [g / eq] (weight per epoxy, WPE). A claim comprising a structural unit derived from an alicyclic compound having two carboxyl groups and a structural unit derived from an aromatic epoxy compound having two epoxy groups. Item 2. The epoxy resin according to Item 1 or 2. The alicyclic compound having two carboxyl groups has the structure of the following formula (I):

(In equation (I), R ₁ is

R ₂ is H or CH ₃ independently, m is an integer of 0 to 2, and ^* represents the coupling position in the equation. ). The epoxy resin according to claim 3. The aromatic epoxy compound having two epoxy groups is selected from the group consisting of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and a combination thereof. The epoxy resin according to claim 3, which is characterized. It is characterized by containing a structural unit derived from an aromatic compound having two −OH groups and a structural unit derived from an alicyclic epoxy compound having two epoxy groups. The epoxy resin according to claim 1 or 2. The aromatic compound having two -OH groups has the structure of the following formula (II):

The epoxy resin according to claim 6, wherein (in formula (II), X _{1 to} X ₈ , R ₁₁ and R ₁₂ are H or CH ₃ independently of each other). The alicyclic epoxy compound having the two epoxy groups

The epoxy resin according to claim 6, wherein n is an integer of 1 to 30 in the formula and a combination thereof. Use of the epoxy resin according to any one of claims 1 to 8 for preparing a composition for packaging. A composition for packaging, which comprises a first epoxy resin and a curing agent, wherein the first epoxy resin is the epoxy resin according to any one of claims 1 to 8. The packaging composition according to claim 10, further comprising a second epoxy resin selected from the group consisting of isocyanurate-based epoxy resins, alicyclic epoxy resins, and combinations thereof. The packaging composition according to claim 10, wherein the curing agent is selected from the group consisting of acid anhydrides, phenolic resins, imidazoles, and combinations thereof. A packaging material, which is produced by curing the packaging composition according to any one of claims 10 to 12. The packaging material according to claim 13, wherein after firing at 150 ° C. for 168 hours, the attenuation value of the light transmittance is less than 23% of the light transmittance before firing.