KR102460588B1 - Metal laminate and printed circuit board comprising the same - Google Patents

Abstract

The present invention relates to a metal laminate including a resin layer made of a polyimide resin composition and a printed circuit board including the same, and the present invention provides a printed circuit board with improved bendability because the metal laminate has excellent withstand voltage can do.

Description

Metal laminate and printed circuit board including the same

The present invention relates to a metal laminate including a resin layer made of a polyimide resin composition and a printed circuit board including the metal laminate.

As electronic devices become lighter, thinner, smaller, and higher-density, the development of slim and easy-to-install flexible printed circuit boards (FPCBs) is diversified. The flexible printed circuit board is composed of a metal layer on which a circuit pattern is formed and a resin layer serving as an insulation, and the resin layer has a basic structure that is present on one or both surfaces of the metal layer.

Such a flexible printed circuit board is required to have excellent bending properties, and as the amount of heat generated by electronic devices increases, there is a limit in obtaining the required bendability. That is, as the light, thin, compact, and high-density of the electronic device is made, the amount of heat generated by the electronic device is increased, and a flexible printed circuit board having excellent heat dissipation is required to improve the increased heat output. At this time, in order to increase the heat dissipation of the flexible printed circuit board, an inorganic filler having thermal conductivity was introduced into the resin layer serving as an insulation. As the mechanical strength of the flexible printed circuit board increased, there was a problem in that the bendability of the flexible printed circuit board was lowered.

Therefore, there is a demand for the development of a flexible printed circuit board having excellent bendability as well as heat dissipation properties.

Republic of Korea Patent Publication No. 2012-0077440

An object of the present invention is to provide a metal laminate having excellent bendability as well as heat resistance, adhesiveness, and heat dissipation properties in order to solve the above problems.

Another object of the present invention is to provide a printed circuit board including the metal laminate.

The present invention in order to achieve the above object, a metal layer; and a resin layer provided on the metal layer, wherein the resin layer is formed of a polyimide resin composition including a first inorganic filler, a second inorganic filler, and a third inorganic filler, and is bent to a radius of 2Φ. A metal laminate with a withstand voltage of 1.5 KV or more is provided when the withstand voltage is evaluated according to the D522 standard.

The metal laminate of the present invention may exhibit an adhesive strength of 1.6 kgf/cm or more when the adhesive strength is evaluated according to the ASTM D2861 standard after being left for 10 hours at a temperature of 121° C. and a pressure of 2 atm.

In addition, the first inorganic filler may be alumina, the second inorganic filler may be boron nitride, and the third inorganic filler may be aluminum nitride.

In addition, the mixing ratio (a: b: c) of the first inorganic filler (a) to the second inorganic filler (b) to the third inorganic filler (c) is 20-50: 1-15: 20-50 It may be a weight ratio.

In addition, the polyimide resin composition is aromatic diamine; aromatic tetracarboxylic dianhydride; and an organic solvent, wherein the aromatic diamine may include a compound represented by Formula 1 below.

[Formula 1]

In Formula 1,

,

,

및

로 표시되는 구조로 이루어진 군에서 선택된다.X and Y are the same as or different from each other, and each independently

,

,

and

It is selected from the group consisting of the structure represented by

Here, the polyimide resin composition, based on 100% by weight of the polyimide resin composition, the first inorganic filler, the second inorganic filler, and the third inorganic filler 7.9 to 23.2% by weight; 7.5 to 9% by weight of the aromatic diamine; 7.8 to 9.4 wt% of the aromatic tetracarboxylic dianhydride; and 61.5 to 73.7 wt% of the organic solvent.

On the other hand, the present invention provides a printed circuit board including the metal laminate.

Since the metal laminate of the present invention exhibits a withstand voltage of 1.5 KV or more in a bent state with a radius of 2Φ, when a printed circuit board is manufactured using it, the bending property (or flexibility) is improved compared to the conventional printed circuit board. A circuit board may be provided.

Hereinafter, the present invention will be described.

1. Metal laminate

The present invention provides a metal laminate having excellent bendability according to a high withstand voltage. The metal laminate of the present invention includes a metal layer; and a resin layer provided on the metal layer, which will be described in detail as follows.

The metal layer (first metal layer) included in the metal laminate of the present invention is a layer on which a circuit pattern is formed. The material constituting the metal layer is not particularly limited, but is preferably copper, tin, gold or silver.

The resin layer included in the metal laminate of the present invention is an insulating layer and is provided on the metal layer. This resin layer is formed of a polyimide resin composition composed of specific components. That is, the resin layer of the present invention is formed of a polyimide resin composition in which an inorganic filler and a polyimide resin varnish solution are mixed, the inorganic filler has characteristic components and various particle sizes, and the polyimide resin varnish solution contains a specific component. It is characterized in that it contains an aromatic diamine, which will be described in detail as follows.

The polyimide resin composition of the present invention includes a plurality of inorganic fillers, that is, a first inorganic filler, a second inorganic filler, and a third inorganic filler.

The first inorganic filler is not particularly limited, but is preferably alumina having excellent thermal conductivity. In this case, the alumina has a spherical shape, and it is preferable to use a mixture of a first alumina having a particle diameter of 0.3 to 0.6 μm and a second alumina having a particle diameter of 2.3 to 4.1 μm. When using alumina in which the first alumina and the second alumina having different particle diameters are used, alumina particles having a small particle diameter are arranged between the alumina particles having a large particle diameter, so that between alumina or other inorganic fillers (second and/or third inorganic particles) It is because the thermal conductivity with filler) can be improved.

The second inorganic filler is not particularly limited, but preferably boron nitride having a particle diameter of 0.2 to 1 μm.

The third inorganic filler is not particularly limited, but is preferably aluminum nitride having a spherical shape and a particle diameter of 10 to 25 μm.

The mixing ratio of the first inorganic filler, the second inorganic filler and the third inorganic filler included in the polyimide resin composition of the present invention is not particularly limited, but considering the physical properties of the resin layer, the first inorganic filler ( The mixing ratio (a:b:c) of a) to the second inorganic filler (b) to the third inorganic filler (c) is preferably 20-50: 1-15: 20-50 by weight. Specifically, when the polyimide resin composition of the present invention includes all of the first alumina, the second alumina, the boron nitride and the aluminum nitride as inorganic fillers, the mixing ratio is not particularly limited, but the first alumina to The mixing ratio of the second alumina to the boron nitride to the aluminum nitride is preferably 5-12:32-44:5-12:32-44 by weight.

The polyimide resin composition of the present invention is an aromatic diamine; aromatic tetracarboxylic dianhydride; and a polyimide varnish solution containing an organic solvent. This is because, by including the aromatic diamine and the aromatic tetracarboxylic dianhydride, heat resistance, adhesiveness, and heat dissipation properties of the resin layer as well as bendability can be improved. In particular, since the aromatic diamine contains a diamine having at least one ester group (a compound represented by the following Chemical Formula 1), when a resin layer (polyimide resin film) is formed with a polyimide varnish solution containing the same, the present invention provides an elongation It is possible to obtain a resin layer exhibiting a high tensile strength of 20% or more and a breaking strength of 100 MPa or more, so that the resin layer of the present invention does not break the resin layer even if a number of inorganic fillers are introduced, and it can exhibit flexible bending properties. have.

The aromatic diamine included in the polyimide resin composition of the present invention is not particularly limited, but is preferably at least one selected from the group consisting of compounds represented by the following Chemical Formulas 1 to 3.

[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,

,

,

및

로 표시되는 구조로 이루어진 군에서 선택되고,X and Y are the same as or different from each other, and each independently

,

,

and

is selected from the group consisting of a structure represented by

,

,

,

,

및

로 표시되는 구조로 이루어진 군에서 선택된다.A and B are the same as or different from each other, and each independently

,

,

,

,

and

It is selected from the group consisting of the structure represented by

The compound represented by Formula 1 is not particularly limited, but is preferably 4-aminophenyl-4-aminobenzoate (APAB). This is because the 4-aminophenyl-4-aminobenzoate can increase the thermal conductivity of the resin layer by imparting crystallinity to the polyimide resin film having a semi-crystalline structure as it has a crystalline structure.

The compound represented by Formula 2 is not particularly limited, but 2,2-bis(4-(4-aminophenoxy)phenyl)propane(2,2-Bis(4-(4-aminophenoxy)phenyl)propane, BAPP ), 2,2-bis (4- [3-aminophenoxy] phenyl) sulfone (2,2-bis (4- [3-aminophenoxy] phenyl) sulfone, m-BAPS) and 4,4'-bis ( It is preferable that at least one selected from the group consisting of 4-aminophenoxy)biphenyl (4,4'-bis(4-aminophenoxy)biphenyl). In addition, the compound represented by Formula 3 is not particularly limited, but 2,2'-(1,2-phenylenebisoxy)dianiline (2,2'-(1,2-phenylenebis(oxy))dianiline, APBN ), (2,2'-dimethyl-4,4'-diaminobiphenyl (2,2'-Dimethyl-4,4'-diaminobiphenyl, m-TB-HG), 1,3-bis (4-amino It is preferable that at least one member selected from the group consisting of phenoxy)benzene (1,3-bis(4-aminophenoxy)benzene, TPE-R) is used. By using the compound, dispersibility or solubility in organic solvents can be improved. This is because the production of the polyimide resin film is facilitated by this.

Here, the mixing ratio of the compound represented by Chemical Formula 1 (first aromatic diamine) and the compound represented by Chemical Formulas 2 and 3 (second aromatic diamine) is not particularly limited, but the mixture of the first aromatic diamine and the second aromatic diamine Based on the total number of moles, a molar ratio of 3:7 to 7:3 is preferable. This is because, as the mixture is mixed in the molar ratio, the thermal conductivity of the resin layer can be improved, and the coatability of the polyimide resin composition can be improved.

The aromatic tetracarboxylic dianhydride contained in the polyimide resin composition of the present invention is not particularly limited, but 3,3',4,4'-benzophenonetetracarboxylic dianhydride (3,3',4 ,4'-Benzophenonetetracarboxylicdianhydride, BTDA), 2,2-bis3,4-dicarboxylphenoxyphenylpropane dianhydride (2,2-Bis(3,4-Dicarboxyphenoxy)phenylpropane dianhydride, BPADA), 2,2 -bis3,4-anhydrodicarboxyphenylhexafluoropropane (2,2-Bis(3,4-anhydrodicarboxyphenyl)hexafluoropropane, 6-FDA), pyromellitic dianhydride (PMDA) and 4,4 It is preferably at least one selected from the group consisting of '-oxydiphthalicanhydride (4,4'-Oxydiphthalicanhydride, ODPA). This is because the adhesiveness of the resin layer can be improved by using such an aromatic tetracarboxylic dianhydride.

The ratio (mixing ratio) of the aromatic diamine and the aromatic tetracarboxylic dianhydride included in the polyimide resin composition of the present invention is not particularly limited, but the number of moles (a) of the aromatic diamine to the aromatic tetracarboxylic dianhydride It is preferable that the ratio (a:b) of the number of moles (b) of is 1 to 1.05:1.

The organic solvent included in the polyimide resin composition of the present invention is not particularly limited as long as it is known in the art, but N-methylpyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), tetrahydrofuran (THF) ), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), cyclohexane, and at least one selected from the group consisting of acetonitrile may be used.

The content of each component included in the polyimide resin composition of the present invention is not particularly limited, but considering the physical properties of the resin layer, based on 100% by weight of the polyimide resin composition, inorganic filler (first inorganic filler + second inorganic filler) filler + total amount of the third inorganic filler) 7.9 to 23.2% by weight; 7.5 to 9% by weight of aromatic diamine; 7.8 to 9.4 wt% of aromatic tetracarboxylic dianhydride; and the remaining amount of the organic solvent satisfying 100% by weight of the composition. At this time, the content of the organic solvent is preferably 61.5 to 73.7% by weight.

The metal laminate of the present invention including a resin layer formed of such a polyimide resin composition exhibits a withstand voltage of 1.5 KV or more when the withstand voltage is evaluated according to ASTM D522 standard in a bent state with a radius of 2Φ. As described above, since the metal laminate of the present invention exhibits high withstand voltage even after bending, the metal laminate of the present invention can be usefully used in the manufacture of a printed circuit board requiring excellent bendability.

Meanwhile, the metal laminate of the present invention may further include a metal layer (second metal layer) on the resin layer. The metal layer is a layer on which a circuit pattern is formed or serves to radiate heat, and a material constituting it is not particularly limited, but is preferably copper, tin, gold or silver.

In addition, the metal laminate of the present invention may further include the above-described resin layer under the metal layer (first metal layer). That is, the metal laminate of the present invention may have a structure of the first resin layer - the metal layer - the second resin layer.

2. Printed circuit board

The present invention provides a printed circuit board including the above-described metal laminate. Specifically, to provide a printed circuit board in which a circuit pattern is formed on a metal layer (a first metal layer and/or a second metal layer) included in the metal laminate. At this time, the resin layer included in the metal laminate serves as an insulating layer. The printed circuit board of the present invention has excellent bendability as well as physical properties such as heat resistance, adhesiveness, and heat dissipation property because the insulating layer is formed of the polyimide resin composition described above.

Hereinafter, the present invention will be described in detail through examples. However, the following examples only illustrate the present invention, and the present invention is not limited by the following examples.

[ Example 1 to 4 and comparative example 1 to 3]

A resin composition having the composition and components shown in Table 1 below was prepared, respectively.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Epoxy Resin 1
(Kukdo Chemical, YD-011) - - - - 2.0g 2.5g 2.7g Epoxy Resin 2
(Kukdo Chemical, YD-019) - - - - 3.1g 3.8g 4.3g Epoxy resin 3
(DOW, DER-383) - - - - 1.8g 2.2g 2.4g hardener
(EMomentive, DICY) - - - - 0.5g 0.6g 0.7g diamine BAPP 2.9g 3.1g 3.2g 2.7g - - - 0.26 mol 0.26 mol 0.26 mol 0.26 mol - - - APBN 2.1g 2.2g 2.3g 1.9g - - - 0.26 mol 0.26 mol 0.26 mol 0.26 mol - - - APAB 3.2g 3.4g 3.5g 2.9g - - - 0.50 mol 0.50 mol 0.50 mol 0.50 mol - - - Aromatic tetracarboxylic dianhydride ODPA 6.8g 7.1g 7.5g 6.2g - - - 0.80 mol 0.80 mol 0.80 mol 0.80 mol - - - BTDA 1.8g 1.9g 1.9g 1.6g - - - 0.20 mol 0.20 mol 0.20 mol 0.20 mol - - first weapon
filler Sumitomo AA-03
(Particle size: 0.3 μm) 1.7g 1.2g 0.8g 2.3g 20.5g 5.5g 0.9g Sumitomo AA-3
(Particle size: 3 μm) 6.5g 4.7g 3.2g 9.3g 13.6g 7.3g 3.5g second weapon
filler Momentive NX-1
(Particle size: 1 μm) 1.7g 1.2g 0.8g 2.3g - 5.4g 0.9g third weapon
filler Toyo, TFZ A15
(Particle size: 15 μm) 6.6g 4.6g 3.1g 9.3g - - 3.4g NMP 66.7g 70.6g 73.7g 61.5g 58.5g 72.7g 81.2g

[ production example 1 to 5 and Comparative Preparation Example 1 to 3] metal laminate Produce

After applying each of the resin compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 3 to a thickness of 100 μm on a copper foil having a thickness of 35 μm, the resin compositions of Examples 1 to 4 were prepared at 200° C., Comparative Examples 1 to The resin composition of 3 was dried at 150° C. for about 1 hour to form a resin layer, respectively. Next, an aluminum foil having a thickness of 2 mm was laminated on the resin layer, and then pressed at 220° C. at a pressure of 100 MPa for 1 hour to prepare a metal laminate, respectively.

[ Experimental example 1] metal laminate Physical property evaluation

The physical properties of the metal laminates prepared in Preparation Examples 1 to 4 and Comparative Preparation Examples 1 to 3 were evaluated in the following manner, and the results are shown in Table 2 below.

1. Thermal conductivity: The thermal conductivity of the resin layer was evaluated according to ASTM D5470 standard.

2. Heat resistance: After floating the metal laminate in a solder bath at 288° C., the time for blister formation was measured.

3. Withstand voltage before bending: The metal laminate was evaluated according to ASTM D522 standard.

4. Withstanding voltage after bending: In a state in which the metal laminate was bent with a radius of 2Φ, it was evaluated according to ASTM D522 standard.

5. Bending property: When the withstand voltage result after bending was 1 KV or more, it was evaluated as 'Good', and when it was less than 1 KV, it was evaluated as 'Bad'.

6. Adhesion: The metal laminate was left at a temperature of 121° C. and a pressure of 2 atm for 10 hours, and then evaluated according to ASTM D2861 standard.

Preparation Example 1 Preparation 2 Preparation 3 Preparation 4 compare
Preparation Example 1 compare
Preparation 2 compare
Preparation 3 Thermal Conductivity (W/mK) 2 1.8 1.6 2.5 0.9 1.1 1.4 heat resistance
(S/D @288) > 10min > 10min > 10min > 10min > 10min > 10min > 10min Withstand voltage before bending (KV) 5.1 5.5 5.6 5.3 4.2 4.5 4.9 Withstand voltage after bending (KV) 2.9 3.1 3.5 2.8 0.1 0.2 0.9 bendability good good good good bad bad bad Adhesion (@1Oz-kgf/cm) 1.7 1.9 2.0 1.6 1.1 1.3 1.4

Referring to Table 2, it can be seen that the metal laminate of the present invention has excellent overall physical properties as the resin layer is formed of the resin composition of Examples 1 to 4. In particular, it can be seen that Preparation Examples 1 to 4, which are metal laminates of the present invention, have excellent bendability as the withstand voltage after bending is 1.5 KV or more.

Claims (7)

metal layer; and
It includes a resin layer provided on the metal layer,
The resin layer is formed of a polyimide resin composition including a first inorganic filler, a second inorganic filler and a third inorganic filler,
The first inorganic filler is alumina, the second inorganic filler is boron nitride, the third inorganic filler is aluminum nitride,
The mixing ratio (a: b: c) of the first inorganic filler (a) to the second inorganic filler (b) to the third inorganic filler (c) is 20-50: 1-15: 20-50 in a weight ratio, ,
Before bending, the withstand voltage is 5.1 kV or more when evaluating the withstand voltage according to ASTM D522 standard,
A metal laminate with a withstand voltage of 1.5 KV or more when evaluated for withstand voltage according to ASTM D522 in a state of being bent with a radius of 2Φ. According to claim 1,
A metal laminate having an adhesive strength of 1.6 kgf/cm or more when evaluated according to ASTM D2861 standard after standing for 10 hours at a temperature of 121° C. and a pressure of 2 atm. delete delete According to claim 1,
The polyimide resin composition is an aromatic diamine; aromatic tetracarboxylic dianhydride; and an organic solvent,
The aromatic diamine is a metal laminate including a compound represented by the following formula (1).
[Formula 1]

In Formula 1,
X and Y are the same as or different from each other, and each independently

,

,

and

It is selected from the group consisting of the structure represented by 6. The method of claim 5,
The polyimide resin composition is based on 100% by weight of the polyimide resin composition,
7.9 to 23.2 wt% of the first inorganic filler, the second inorganic filler, and the third inorganic filler;
7.5 to 9% by weight of the aromatic diamine;
7.8 to 9.4 wt% of the aromatic tetracarboxylic dianhydride; and
A metal laminate comprising 61.5 to 73.7 wt% of the organic solvent. A printed circuit board comprising the metal laminate of any one of claims 1, 2, and 5 to 6.