KR20190091393A - flexible metal clad laminate and THERMOPLASTIC POLYIMIDE PRECORSOR COMPOSITION for flexible metal clad laminate - Google Patents

Abstract

The present invention relates to a flexible metal clad laminate and, more specifically, relates to a flexible metal clad laminate having a high modulus, excellent laser processing characteristics, and improved bonding characteristics with respect to metal foil, in particular, to aluminum foil, a flexible printed circuit board having the same, and a thermoplastic polyimide precursor composition for a flexible metal clad laminate.

Description

Flexible poly clad laminate and THERMOPLASTIC POLYIMIDE PRECORSOR COMPOSITION COMPOSITION for flexible metal clad laminate

The present invention relates to a flexible metal laminate, wherein a flexible metal laminate and a flexible printed circuit board including the same, having high modulus, good laser processing characteristics, and improved adhesion to metal foil, in particular, to aluminum foil. And a thermoplastic polyimide precursor composition for a ductile metal laminate.

Flexible Metal Clad Laminate (FPCB) is used as a basic raw material for FPCB products that make up the circuit of electronic devices such as smartphones.

Recently, in accordance with the development of electronic devices and the demand for complex functions, high-speed transmission, low weight, thinness, and miniaturization of flexible printed circuit boards are progressing day by day. In order to meet these demands, fine patterning is progressing in terms of processing flexible printed circuit boards. In order to cope with such a trend, research and development are needed to make the polyimide layer of flexible metal clad laminates have a small dimensional deviation and good workability.

Generally, it is known that the higher the modulus of the polyimide layer of the ductile metal laminate, the less the dimensional deviation is induced. However, the higher the modulus of the polyimide adhesive layer, the lower the adhesive force. .

In the FPCB process, a flexible metal laminate is laminated in several layers to perform laser hole processing for signal transmission between layers. In order to realize high modulus, the use of monomers having short unit length and rigid properties such as p-PDA tends to deteriorate laser machinability. Therefore, it is necessary to study a flexible metal laminate that has high modulus and satisfies the properties of laser workability at the same time.

SUMMARY OF THE INVENTION The present invention has been made to solve a conventional problem, and an object of the present invention is to provide a ductile metal laminate that satisfies physical properties with high modulus and excellent laser workability.

In addition, the present invention is excellent in adhesion strength not only copper foil but also high purity aluminum foil with 1.0 kgf / cm or more, and an object of the present invention is to provide a flexible metal laminate with excellent overall physical properties such as dimensional stability, solder bath heat resistance and curl characteristics. .

In addition, an object of the present invention is to provide a flexible metal laminate that has a coefficient of thermal expansion similar to that of aluminum foil, overcomes curling and poor dimensional stability, and can express the physical properties of copper foil.

In addition, the present invention does not require a separate adhesive resin layer such as an epoxy resin in order to secure the adhesion to copper foil or aluminum foil, using a flexible thermoplastic polyimide laminate (TPI layer) with excellent adhesive strength The purpose is to provide.

One aspect of the present invention for achieving the above object is a flexible metal foil comprising a metal foil on one side or both sides of a polyimide laminate in which a first thermoplastic polyimide layer, a base polyimide layer, and a second thermoplastic polyimide layer are sequentially laminated. As a laminate,

The first thermoplastic polyimide layer and the second thermoplastic polyimide layer include a polyimide derived from an acid anhydride and diamine,

The diamine is a soft metal laminate comprising at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene.

Another embodiment of the present invention provides an acid anhydride comprising biphenyltetracarboxylic dianhydride and a polyamic acid derived from diamine comprising m-tolidine and 1,3-bis (4-aminophenoxy) benzene. It is a thermoplastic polyimide precursor composition for flexible metal laminates containing.

The flexible metal laminate according to the present invention can provide a flexible metal laminate having high modulus, excellent adhesion to the metal foil, and excellent laser processing characteristics.

In addition, it is excellent in adhesion to aluminum foil as well as copper foil, it is possible to provide a flexible metal foil laminate excellent in dimensional stability without the occurrence of curl when bonding to aluminum foil.

1 is a cross-sectional photograph showing a laser processing characteristic according to an embodiment of the present invention, a cross-sectional photograph showing no residue.
2 is a cross-sectional photograph showing a laser processing characteristic according to an aspect of the present invention, a cross-sectional photograph showing that there is a residue (red line notation).

DETAILED DESCRIPTION Hereinafter, the present invention will be described in more detail with reference to the accompanying examples or embodiments. However, the following specific examples or examples are only one reference for describing the present invention in detail, but the present invention is not limited thereto and may be implemented in various forms.

Also, unless defined otherwise, all technical and scientific terms have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used in the description in the present invention are only for effectively describing specific embodiments and are not intended to limit the present invention.

Also, the singular forms used in the specification and the appended claims may be intended to include the plural forms as well, unless the context clearly indicates otherwise.

One aspect of the present invention is a flexible metal laminate comprising a metal foil on one or both sides of a polyimide laminate in which a first thermoplastic polyimide layer, a base polyimide layer, and a second thermoplastic polyimide layer are sequentially stacked,

The first thermoplastic polyimide layer and the second thermoplastic polyimide layer include a polyimide derived from an acid anhydride and diamine,

The diamine is a soft metal laminate comprising at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene.

In one embodiment of the present invention, the acid anhydride may be one containing 70 mol% or more of biphenyltetracarboxylic dianhydride.

In one aspect of the present invention, the first thermoplastic polyimide layer and the second thermoplastic polyimide layer may have a modulus of 5 GPa or more and an adhesive force with a metal foil of 1.0 kgf / cm or more at 25 ° C.

In one aspect of the present invention, the first thermoplastic polyimide layer and the second thermoplastic polyimide layer may be 5 wt% pyrolysis temperature of 530 ° C. or less.

In one aspect of the invention, the metal foil may be an aluminum foil.

In one aspect of the present invention, the flexible metal foil laminate may have an adhesive force between the aluminum foil and the first thermoplastic polyimide layer and the aluminum foil and the second thermoplastic polyimide layer satisfying Equations 1 and 2 below.

[Equation 1]

60% ≤ AF100 ≤ 90%

In Equation 1, AF100 = (adhesion measured at 100 ° C./adhesion measured at 25 ° C.) × 100.

[Equation 2]

50% ≤ AF200 ≤ 90%

In Equation 2, AF200 = (adhesion measured at 200 ° C./adhesion measured at 25 ° C.) × 100.

Another aspect of the invention includes an acid anhydride comprising biphenyltetracarboxylic dianhydride and a polyamic acid derived from diamine comprising m-tolidine and 1,3-bis (4-aminophenoxy) benzene It is a thermoplastic polyimide precursor composition for flexible metal laminates.

In one aspect of the precursor composition of the present invention, the diamine may be at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene.

In one aspect of the precursor composition of the present invention, the acid anhydride may be 70 mol% or more of biphenyltetracarboxylic dianhydride.

Hereinafter, each configuration of the present invention will be described in more detail.

In general, in the case of the thermoplastic polyimide layer, unlike the base polyimide layer, the adhesion property to the metal foil is very important. In order to secure the adhesive properties, when the unit molecule is long and designed in a structure including various functional groups, modulus is reduced, and thus it is difficult to realize high modulus.

The inventors of the present invention provide a thermoplastic polyimide layer when m-tolidine and 1,3-bis (4-aminophenoxy) benzene (TPER) are included as diamine monomers for forming the thermoplastic polyimide layer. The modulus of metal is improved, the adhesion to metal foil, in particular, the adhesion to aluminum foil as well as copper foil is improved, and the laser processing characteristics are improved, so that almost no residue occurs, It has been found that it can be provided.

Almost no residue during laser processing means that the drilled polyimide does not remain inside the hole during hole formation. FIG. 1 illustrates a cross section of one embodiment in which no residue occurs, and FIG. 2 shows a red line. As shown by the figure, the cross section of one aspect in case a residue generate | occur | produces is shown. The presence or absence of residue in the laser processing may be a hole-free condition, when there is no residue in the hole when the hole size is 120㎛ at 250 mm / sec processing speed (velocity) at laser power 2W. It may be described in more detail by the measuring method described below.

In addition, the diamine monomers include m-tolidine and m-tolidine and 1,3-bis (4-aminophenoxy) benzene (TPER), each of which contains at least 30 mol% of the diamine content. The present invention was completed by finding that the modulus is further improved and the adhesion to metal foil, particularly aluminum foil, is further improved. 40 mole% or less except for m-tolidine and 1,3-bis (4-aminophenoxy) benzene (TPER) may be used without limitation as long as it is normally used as a diamine monomer.

Specifically, the flexible metal laminate according to one embodiment of the present invention is 30 mol% or more of m-tolidine and 1,3-bis (4-aminophenoxy) benzene (TPER) as the diamine monomer. By including, the modulus of the thermoplastic polyimide layer adhered to the metal foil is 5 GPa or more, and the adhesive force can satisfy the physical properties of 1.0 kgf / cm or more at the same time. By satisfying the above physical properties at the same time, the residue hardly occurs during laser processing, and at the same time excellent adhesion to not only copper foil but also aluminum foil, curl does not occur, it is possible to express the physical properties excellent dimensional stability. In addition, it can satisfy the physical properties of 5% by weight pyrolysis temperature of 530 ℃ or less. That is, the flexible metal laminate according to an aspect of the present invention has a high modulus and excellent adhesion to copper foil and aluminum foil, and at the same time has a low thermal decomposition temperature, thereby producing a polyimide laminate in a flexible printed circuit board manufacturing process. By reducing the rate of dimensional change of the microcircuit can be made possible to manufacture a stable and multi-layer structure. In addition, the effect of forming a hole without polyimide residue in the hole formed during laser processing can be simultaneously achieved.

Specifically, the modulus is 5 GPa or more, and more specifically, 5 to 6 GPa, so that the change rate due to mechanical, chemical and thermal deformation is low, and when applied to the flexible printed circuit board, it is possible to prevent sudden changes in the circuit intervals. It may be advantageous for circuit formation. In addition, in order to manufacture a flexible printed circuit board having a multilayer structure, when the flexible metal laminate is laminated in multiple layers, the dimensional change rate is small before and after pressing to prevent distortion between the land part and the hole, thereby manufacturing the multilayer flexible circuit board. May be advantageous. In addition, by satisfying the physical properties of the adhesive strength is more than 1.0 kgf / cm, more specifically 1.0 to 2.0 kgf / cm, the adhesion to not only copper foil but also aluminum foil is improved, the thermal decomposition temperature is 530 ℃ or less, more specifically 500 ~ 530 It can satisfy the physical properties of ℃ ℃ does not generate a polyimide residue in the hole during the drilling process is excellent in ease of processing, and can be improved in the hole plating reliability.

The flexible metal laminate according to an aspect of the present invention may include a metal foil on one surface of a polyimide laminate in which a first thermoplastic polyimide layer, a base polyimide layer, and a second thermoplastic polyimide layer are sequentially stacked. More specifically, the metal foil, the first thermoplastic polyimide layer, the base polyimide layer, and the second thermoplastic polyimide layer may be sequentially stacked.

In addition, the flexible metal laminate according to an aspect of the present invention may be one containing a metal foil on both sides of the polyimide laminate in which the first thermoplastic polyimide layer, the base polyimide layer and the second thermoplastic polyimide layer are sequentially laminated. have. More specifically, the first metal foil, the first thermoplastic polyimide layer, the base polyimide layer, the second thermoplastic polyimide layer, and the second metal foil may be sequentially stacked.

In one embodiment of the present invention, the flexible metal laminate is excluded that the first thermoplastic polyimide layer, the base polyimide layer, and the second thermoplastic polyimide layer are made of a thermoplastic polyimide layer alone, not a polyimide laminate sequentially stacked. It doesn't happen. That is, the flexible metal foil laminate including the metal foil on one or both sides of the thermoplastic polyimide layer is also included in the scope of the present invention. In addition, the thermoplastic polyimide layer may have a modulus of 5 GPa or more and an adhesive force of 1.0 kgf / cm or more.

In one aspect of the present invention, the metal foil is not limited as long as it is commonly used in the art, specifically, for example, may be copper foil or aluminum foil. When the metal foil is formed on both sides, they may be made of the same or different metals. Preferably it may be the same metal from the viewpoint of improving the dimensional stability.

In one aspect of the present invention, the aluminum foil may be a surface of the aluminum as a high-purity simple rolling material of 99.3% or more. More specifically, the 10-point average roughness Rz may be 0.5 to 2.0 μm, and the electrical conductivity may be high purity aluminum foil of 50 IACS (%) or more.

In one embodiment of the present invention, the thickness of the metal foil is not limited but may be 2 to 105 μm, and more specifically 6 to 105 μm. When metal foils are laminated on both sides of the polyimide laminate, the thicknesses of the metal foils on both sides may be the same or different, but may be the same thickness to realize uniform physical properties. The metal foil may be an electrolytic foil, a rolled foil, or the like, but may be variously applied depending on the intended use.

In one aspect of the invention, the first thermoplastic polyimide layer and the second thermoplastic polyimide layer comprise a polyimide derived from an acid anhydride and diamine, wherein the diamine is m- tolidine and 1,3-bis (4 -Aminophenoxy) benzene. In this case, but is not limited to, the acid anhydride may include biphenyltetracarboxylic dianhydride (BPDA).

The acid anhydride is, in addition to biphenyltetracarboxylic dianhydride, pyromellitic dianhydride (PMDA), 4,4'-hexafluoroisopropylidene diphthalic anhydride (6FDA), benzophenonetetracarbide One or more acid anhydrides selected from cyclic dianhydride (BTDA), 4,4'-oxydiphthalic dianhydride (ODPA) and bisdicarboxyphenoxy diphenylsulfide dianhydride (BDSDA) are further added. It may include, but is not limited thereto. More preferably, more than 70 mol%, more specifically, 70 to 100 mol% of biphenyltetracarboxylic dianhydride (BPDA) may be used, and it may be more preferable to implement a desired physical effect in the above range. Can be.

The diamine may include m-tolidine and 1,3-bis (4-aminophenoxy) benzene to satisfy physical properties of 5 GPa or more of modulus and 1.0 kgf / cm or more of adhesion. More specifically, by including at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene, it is possible to simultaneously satisfy physical properties of 5 GPa or more of modulus and 1.0 kgf / cm or more of adhesion. Can be. More specifically, it may be one containing 30 to 70 mol% of m-tolidine and 30 to 70 mol% of 1,3-bis (4-aminophenoxy) benzene.

In addition, in addition to m-tolidine and 1,3-bis (4-aminophenoxy) benzene, the diamine may further include a diamine commonly used as necessary. Specifically, for example, p-phenylenediamine (p-PDA), 2,2-bis [4- (4-aminophenoxy) phenyl] propane (BAPP) and 4,4'-diaminodiphenyl ether ( ODA), etc. may be any one or two or more selected. That is, at least 30 mol% of m-tolidine, at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene, and excluding m-tolidine and 1,3-bis (4-aminophenoxy) benzene It may be one containing 40 mol% or less of diamine. More specifically, it may include 30 to 70 mol% of m-tolidine, 30 to 70 mol% of 1,3-bis (4-aminophenoxy) benzene, and 20 to 40 mol% of other diamines.

More specifically, the diamine may include m-tolidine, 1,3-bis (4-aminophenoxy) benzene, and p-phenylenediamine (p-PDA). In this case, the content of p-phenylenediamine may be 20 mol% or more, more specifically, 20 to 40 mol%. At this time, the m- tolidine may be 30 to 50 mol%, 1,3-bis (4-aminophenoxy) benzene may contain 30 to 50 mol%.

In one aspect of the present invention, the thickness of the first thermoplastic polyimide layer and the second thermoplastic polyimide layer is not limited, but may be 2 to 50 μm, more specifically 3 to 38 μm. Despite reducing the overall thickness of the ductile metal laminate in the above range, high modulus and low pyrolysis temperature can be realized, and when applied to the ductile metal laminate, excellent laser drill processing characteristics, there is no residue, but It is not limited to this.

In one aspect of the present invention, the flexible metal foil laminate may have an adhesive force between the aluminum foil and the first thermoplastic polyimide layer and the aluminum foil and the second thermoplastic polyimide layer satisfying Equations 1 and 2 below.

[Equation 1]

60% ≤ AF100 ≤ 90%

In Equation 1, AF100 = (adhesion measured at 100 ° C./adhesion measured at 25 ° C.) × 100.

[Equation 2]

50% ≤ AF200 ≤ 90%

In Equation 2, AF200 = (adhesion measured at 200 ° C./adhesion measured at 25 ° C.) × 100.

That is, the first thermoplastic polyimide layer and the second thermoplastic polyimide layer according to an aspect of the present invention may have excellent adhesion to copper foil or aluminum foil at room temperature, more specifically, at 25 ° C. of 1.0 kgf / cm or more. , The adhesive force to the aluminum foil at a high temperature may be maintained at 50% or more. More specifically, as shown in Equation 1, the adhesive force measured at 100 ℃ may be maintained at 60% or more than the adhesive strength measured at 25 ℃, the adhesive force measured at 200 ℃ compared to the adhesive strength measured at 25 ℃ 50% or more may be maintained. As described above, the first thermoplastic polyimide layer and the second thermoplastic polyimide layer according to an aspect of the present invention may exhibit more excellent physical properties of adhesion to aluminum foil in a heated state.

Typically, the adhesion to the metal foil at a high temperature is generally significantly lower than room temperature, but the first thermoplastic polyimide layer and the second thermoplastic polyimide layer according to an embodiment of the present invention are m-tolidine and 1,3-bis ( It was confirmed that the adhesion at high temperature was maintained at a good level by including 4-aminophenoxy) benzene. In addition, the adhesive force at room temperature showed a higher adhesive strength of the copper foil than the aluminum foil, but it was found that the adhesive strength of the aluminum foil is more excellent than the copper foil at a high temperature.

In one aspect of the invention, the base polyimide layer may be made of a polyimide resin typically used in the art, it is not limited. Specifically, for example, 4,4'-diaminodiphenyl ether, p-phenylene diamine, etc. may be used as the diamine component, and biphenyl-tetracarboxylic acid dianhydride, pyromelli as the acid anhydride component. Tic anhydride and the like.

In one embodiment of the present invention, the thickness of the base polyimide layer is not limited, but may be 2 to 50 μm, more specifically 3 to 38 μm.

The following describes a method of manufacturing the flexible metal laminate according to one aspect of the present invention.

The first aspect of the method for producing the flexible metal laminate according to one aspect of the present invention

(a) coating and drying the first thermoplastic polyimide precursor composition on one surface of the metal foil to form a first thermoplastic polyimide precursor layer;

(b) applying and drying a base polyimide precursor composition on the first thermoplastic polyimide precursor layer to form a base polyimide precursor layer;

(c) applying and drying a second thermoplastic polyimide precursor composition on the base polyimide precursor layer to form a second thermoplastic polyimide precursor layer; And

(d) imidating the laminated polyimide laminate;

It may be to include.

The second aspect of the method for producing the flexible metal laminate according to one aspect of the present invention

Iii) applying and drying the first thermoplastic polyimide precursor composition on the substrate to form a first thermoplastic polyimide precursor layer;

Ii) applying and drying a base polyimide precursor composition on the first thermoplastic polyimide precursor layer to form a base polyimide precursor layer;

Iii) applying and drying a second thermoplastic polyimide precursor composition on the base polyimide precursor layer to form a second thermoplastic polyimide precursor layer;

Iii) imidating the laminated polyimide laminate; And

V) laminating a metal foil on one or both surfaces of the imidized laminate and then heating and compressing the same.

The third aspect of the method for producing the flexible metal laminate according to one aspect of the present invention

(a) coating and drying the first thermoplastic polyimide precursor composition on one surface of the metal foil to form a first thermoplastic polyimide precursor layer;

(b) applying and drying a base polyimide precursor composition on the first thermoplastic polyimide layer to form a base polyimide precursor layer;

(c) applying and drying a second thermoplastic polyimide precursor composition on the base polyimide precursor layer to form a second thermoplastic polyimide precursor layer;

(d) imidating the stacked laminates; And

(e) laminating a metal foil on the imidized laminate and then heating and compressing it.

In one aspect of the present invention, the first thermoplastic polyimide precursor composition and the second thermoplastic polyimide precursor composition may be the same or different compositions from each other. The precursor composition may be one containing an organic solvent. The organic solvent is not particularly limited in kind, and specific examples thereof include dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), and dimethylformsulfoxide (DMSO). ), Acetone, diethyl acetate, m-cresol and the like. Preferably dimethylacetamide or N-methyl-2-pyrrolidone may be used. In addition, the content of the organic solvent may be appropriately selected in consideration of the molecular weight of the thermoplastic polyamic acid is a copolymer derived from the monomers, it may be 80 to 97% by weight of the total composition. More preferably, it is 85 to 95 weight%. That is, the content of solids is more preferably 3 to 20% by weight, preferably 5 to 15% by weight.

In one aspect of the present invention, the coating method may be selected from knife coating, roll coating, die coating, curtain coating, casting coating, and the like. It may be carried out through, but is not limited thereto.

In one aspect of the invention, the drying may be dried by heat treatment for 1 minute to 2 hours, preferably 1 to 1 hour at 100 to 200, for example at 100 to 200. In addition, the drying may be carried out in a separate drying oven, but is not necessarily limited thereto.

In one aspect of the present invention, the imidation can be cured through a known imidization method, for example, thermal imidization method, chemical imidization method, thermal imidization method and chemical imidization method in combination. However, it is not limited thereto. In addition, prior to thermal imidization, a dehydrating agent and an imidization catalyst may be added to perform chemical imidization. The dehydrating agent is not limited as long as it is conventionally used, and specifically, for example, one or a mixture of two or more selected from acetic anhydride, phthalic anhydride, maleic anhydride and the like may be used. Can be. The imidation catalyst is not limited as long as it is conventionally used, and specifically, for example, pyridine, isoquinoline, β-quinoline, and any one or two or more mixtures selected from the like may be used. May be, but is not necessarily limited thereto.

The thermal imidization method may be to perform a heat treatment step by step. Preferably the first heat treatment at 80 to 100 ℃, more specifically at 90 to 100 ℃ for 1 minute to 2 hours, the second heat treatment at 100 to 200 ℃, more specifically at 150 to 200 ℃ for 1 minute to 2 hours, 250 To 300 ° C, more specifically, may be to perform a stepped heat treatment of the third heat treatment for 1 minute to 2 hours at 280 to 300 ℃. At this time, the stepped heat treatment may be to increase the temperature in the range of preferably 1 to 20 ℃ / min during each step movement. When heat treatment is performed at once without heat treatment step by step as described above, the solvent that is not dried may be trapped in the film and may not be evaporated even at high temperature heat treatment. Therefore, the solvent may be dried and imidized by heat treatment in multiple stages. It may be to practice.

In one aspect of the present invention, the hot pressing may be performed by any one or more devices selected from, for example, a heat press, a vacuum press, a laminator, a vacuum laminator, a thermal roll laminator, a vacuum thermal roll laminator, and the like, but is not limited thereto. It doesn't happen.

In addition, the present invention can provide a flexible printed circuit board comprising a flexible metal laminate according to an aspect of the present invention described above.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the following Examples and Comparative Examples are only examples for explaining the present invention in more detail, the present invention is not limited by the following Examples and Comparative Examples.

Hereinafter, physical properties were measured as follows.

1) Modulus

The modulus was measured according to the IPC-TM-650.2.4.18.3 measuring method.

2) adhesion

In order to measure the peel strength between polyimide resin and metal foil, 180 ° peeling strength was measured by using universal testing machine (UTM) after patterning metal layer to 1mm width according to JIS C6471. .

3) 5 wt% Pyrolysis temperature (Td)

The TGA (TGA Q500 by TA) was used to measure the thermogravimetric temperature by raising the temperature from room temperature (25 ° C.) to 900 ° C. under a nitrogen atmosphere at 10 ° C./min. At this time, in the measured thermogravimetric analysis, the weight at 150% by weight was measured based on the initial weight based on the weight at 150 ° C.

4) laser hole processing characteristics

When forming holes under the following laser conditions, the residue area was evaluated. The residue was subjected to the drilling process of the polyimide laminate surface exposed after removing one copper foil surface of the continuous metal foil laminate under the following copper foil laser conditions under the following polyimide laminate laser conditions. In the drilling, holes were formed at a distance spaced at regular intervals in an area of 20 mm × 20 mm, and at this time, 50 holes were identified. It was judged that there was no residue if no thing and polyimide remained. The residue area means the number of holes in which 50 residues remain.

Polyimide laminate surface (Power, Velocity): 2W, 250mm / sec speed

Hole diameter: 120㎛

[Production Example 1]

(Preparation of thermoplastic polyimide precursor composition)

In a nitrogen atmosphere, m-toluidine and 1,3-bis (4-aminophenoxy) benzene (TPER) were added to N, N-dimethylacetamide (DMAc) in a reactor, followed by sufficient stirring. Tetracarboxylic dianhydride (BPDA) was added thereto, stirred until dissolved, and dissolved and reacted to prepare a thermoplastic polyimide precursor composition.

At this time, the content of each monomer was added to the mol% as shown in Table 1, the solid content was adjusted to 10% by weight, the temperature of the reactor was maintained at 30 ℃.

[Production Examples 2 to 6]

Except that prepared in Example 1 to adjust the content and type of monomer as shown in Table 1 was carried out in the same manner.

The thermoplastic polyimide precursor composition prepared in Preparation Examples 1 to 6 was subjected to solution casting on an glass substrate using an applicator. Then, after the heat treatment for 20 minutes at 140 ℃ in a drying oven, the temperature was raised from 350 ℃ to 350 ℃ in an oven in which nitrogen was added to maintain a 30 minutes to prepare a thermoplastic polyimide film. Thereafter, the film was cooled at room temperature and the film formed on the glass substrate was separated from the substrate to obtain a polyimide film having a thickness of 20 μm. The modulus of the prepared polyimide film was measured and shown in Table 1 below. In addition, the laminated copper foil (BHY-82F-HA-V2 manufactured by JX Corporation) having a thickness of 12 μm was laminated on the manufactured polyimide film, and then bonded using a high temperature laminator to prepare a flexible metal laminate, and then at room temperature (25 ° C.). ), Copper foil adhesion was measured.

Acid anhydride
(mole%) Diamine
(mole%) Modulus
(GPa) Copper foil adhesion
(Kgf / cm) BPDA m-Tolidine P-PDA TPER BAPP Preparation Example 1 100 50 0 50 - 5.2 1.2 Preparation Example 2 100 40 20 40 - 5.1 1.1 Preparation Example 3 100 30 40 30 - 5.1 1.0 Preparation Example 4 100 50 30 20 - 5.4 0.4 Preparation Example 5 100 20 0 80 - 2.4 1.2 Preparation Example 6 100 - - - 100 2.3 1.0 Preparation Example 7 100 40 0 60 0 5.1 1.4

In Table 1 above, P-PDA is p-phenylene diamine and BAPP is 2,2-bis [4- (4-aminophenoxy) phenyl] propane.

As shown in Table 1, when both m-Tolidine and TPER included more than 30mol%, Modulus was also confirmed to be high value of 5GPa or more, and the adhesion was also excellent as more than 1.0kgf / cm.

Table 2 below measures the normal temperature (25 ° C.) adhesion of the thermoplastic polyimide layer and the metal foil prepared in the compositions of Preparation Example 1 and Preparation Example 6.

Metal foil Metal foil information Composition of Preparation Example 6
(BPDA 100 mol% / BAPP 100 mol%) Composition of Preparation Example 1
BPDA 100 mol% / m-Tolidine 50 mol% + TPER 50 mol% Copper foil 12 ㎛ thick rolled copper foil
GHY5-82F-HA-V2
Matte surface roughness 1 μm 1.0kgf / cm 1.2kgf / cm Aluminum foil 70 ㎛ thick
Roughness 0.5 ~ 1 ㎛
No additional surface treatment for improved adhesion 0.6kgf / cm 1.1kgf / cm

As shown in Table 2, the composition of Preparation Example 6 and Preparation Example 1 satisfied the level of 1.0kgf / cm or more for the copper foil. However, as for aluminum foil, it was found that the composition of Preparation Example 1 containing 30 mol% or more of m-tolidine and 1,3-bis (4-aminophenoxy) benzene was better than that of Preparation Example 6. . In addition, the aluminum foil was found to satisfy the level of 1.0kgf / cm or more.

Table 3 below measures the normal temperature (25 ° C.) adhesion of the thermoplastic polyimide layer and the metal foil prepared in the composition of Preparation Example 7.

Preparation Example 7 Adhesion According to Composition of Composition materials Equipment information Measuring temperature Adhesive force (kgf / cm) Aluminum foil
Lotte Aluminum
A1235H18
Thickness 50 ㎛ Room temperature (25 ℃) 1.2 100 ℃ 1.0 200 ℃ 0.7 Cu Foil JX
GHY5-82F-HA-V2
18㎛ thick Room temperature (25 ℃) 1.4 100 ℃ 0.8 200 ℃ 0.4

Typically, the adhesion to the metal foil at a high temperature is generally significantly lower than room temperature, but as shown in Table 3, the thermoplastic polyimide layer according to one embodiment of the present invention is m-tolidine and 1,3-bis (4). It was confirmed that the adhesion at high temperature was maintained at a good level by including -aminophenoxy) benzene. In addition, the adhesive force at room temperature showed a higher adhesive strength of the copper foil than the aluminum foil, but it was found that the adhesive strength of the aluminum foil is more excellent than the copper foil at a high temperature. This is presumably because aluminum foil has better oxidation characteristics than copper foil.

Example 1

After applying the thermoplastic polyimide precursor composition prepared in the same manner as in Preparation Example 1 on the rolled copper foil (BHY-82F-HA-V2 of JX Co., Ltd.) having a thickness of 12 ㎛ thickness, 20 at 140 ℃ It dried for 1 minute and formed the 1st thermoplastic polyimide precursor layer. After applying the base polyimide precursor composition on the first thermoplastic polyimide precursor layer and dried for 20 minutes at 140 ℃ to form a base polyimide precursor layer. The thermoplastic polyimide precursor composition prepared in the same manner as in Preparation Example 1 was applied to the base polyimide precursor layer by using the composition shown in Table 2, and dried at 140 ° C. for 20 minutes to form a second thermoplastic polyimide precursor layer. . Subsequently, in a roll-to-roll infrared curing machine, the temperature was raised to 380 ° C. at a temperature increase rate of 2 ° C./min, and cured. A flexible metal laminate having a total thickness of 25 μm was prepared.

A 12 μm thick rolled copper foil (BHY-82F-HA-V2 manufactured by JX) was laminated on the second thermoplastic polyimide layer of the imidized laminate, and then bonded using a high temperature laminator to produce a flexible metal laminate. It was. The 5 wt% pyrolysis temperature (Td) and the laser hole processing characteristics of the manufactured flexible metal laminate were shown in Table 4 below.

The base polyimide precursor composition uses 4,4'-diaminodiphenyl ether and p-phenylene diamine in a 1: 1 molar ratio as the diamine component, and biphenyl-tetracarboxylic acid dianhydride as the acid anhydride component. It was prepared and used in the same manner as in Preparation Example 1 except that the melionic anhydride was mixed in a 1: 1 molar ratio.

[Examples 2 to 7]

A flexible metal laminate was prepared in the same manner as in Example 1 except for changing the composition of the thermoplastic polyimide precursor composition as shown in Table 4 below. The 5 wt% pyrolysis temperature (Td) and the laser hole processing characteristics of the manufactured flexible metal laminate were shown in Table 4 below.

[Comparative Examples 1 to 6]

A flexible metal laminate was prepared in the same manner as in Example 1 except for changing the composition of the thermoplastic polyimide precursor composition as shown in Table 4 below. The 5 wt% pyrolysis temperature (Td) and the laser hole processing characteristics of the manufactured flexible metal laminate were shown in Table 4 below.

5 wt% pyrolysis temperature (Td) and laser hole processing characteristics of the flexible metal laminates prepared in Examples and Comparative Examples were evaluated and shown in Table 4 below. In addition, the adhesion at room temperature (25 ° C.) was measured and shown in Table 4 below.

TPI composition Acid anhydride
(mole%) Diamine (mol%) Td
(5 wt%) Laser Hole Machining Characteristics BPDA TPER p-PDA m-Tolidine Residues Example 1 100 50 20 30 530 5 Example 2 100 50 0 50 520 4 Example 3 100 40 0 60 513 4 Example 4 100 30 40 30 530 5 Example 5 100 70 0 30 523 3 Example 6 100 30 0 70 510 2 Example 7 100 60 0 40 520 3 Comparative Example 1 100 50 50 0 572 21 Comparative Example 2 100 50 40 10 548 13 Comparative Example 3 100 50 30 20 538 8 Comparative Example 4 100 20 60 20 545 10 Comparative Example 5 100 20 30 50 543 12 Comparative Example 6 100 0 50 50 540 11

Aluminum foil was 70 micrometers in thickness, roughness 0.5-1 micrometer, and the thing which did not give further surface treatment for the adhesive force improvement was used.

As the copper foil, a rolled copper foil having a thickness of 12 μm was used, and GHY5-82F-HA-V2 was used, and a Matte surface roughness of 1 μm was used.

As shown in Table 4, the content of m-Tolidine and 1,3-bis (4-aminophenoxy) benzene (TPER) was found to be more than 30 mol% and Td below 530 ° C, respectively. In addition, the lower the decomposition temperature was confirmed that the laser workability is improved.

Table 5 shows the laser hole processability under various conditions using the flexible metal laminate of Example 1.

POWER 70% 80% 100% 120% 130% 150% Velocity 140% PI residue PI residue PI residue No residue No residue No residue 120% PI residue PI residue No residue No residue No residue No residue 110% No residue No residue No residue No residue No residue No residue 100% No residue No residue No residue No residue No residue No residue 90% No residue No residue No residue No residue No residue No residue 80% No residue No residue No residue No residue No residue No residue 60% No residue No residue No residue No residue No residue No residue

As shown in Table 5, the soft metal laminate according to Example 1 of the present invention confirmed that the residue hardly occurs. In addition, some residues were generated at low power and high velocity, but the number of residues was less than 5, indicating that almost no residues occurred.

Claims (9)

A flexible metal foil laminate comprising metal foil on one or both sides of a polyimide laminate in which a first thermoplastic polyimide layer, a base polyimide layer, and a second thermoplastic polyimide layer are sequentially stacked,
The first thermoplastic polyimide layer and the second thermoplastic polyimide layer include a polyimide derived from an acid anhydride and diamine,
The diamine is a flexible metal laminate comprising at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene. The method of claim 1,
The acid anhydride is a flexible metal laminate comprising at least 70 mol% of biphenyl tetracarboxylic dianhydride. The method of claim 1,
The first thermoplastic polyimide layer and the second thermoplastic polyimide layer have a modulus of 5 GPa or more and an adhesive strength with a metal foil of 25 kg or more at 1.0 kgf / cm or more. The method of claim 1,
The first thermoplastic polyimide layer and the second thermoplastic polyimide layer have a 5 wt% pyrolysis temperature of 530 ° C. or less. The method of claim 1,
The metal foil is a flexible metal laminate of aluminum foil. The method of claim 5,
The flexible metal laminate is a flexible metal laminate in which the adhesive force between the aluminum foil and the first thermoplastic polyimide layer and the aluminum foil and the second thermoplastic polyimide layer satisfies the following Equations 1 and 2.
[Equation 1]
60% ≤ AF100 ≤ 90%
In Equation 1, AF100 = (adhesion measured at 100 ° C./adhesion measured at 25 ° C.) × 100.
[Equation 2]
50% ≤ AF200 ≤ 90%
In Equation 2, AF200 = (adhesion measured at 200 ° C./adhesion measured at 25 ° C.) × 100. Thermoplastics for ductile metal laminates comprising acid anhydrides comprising biphenyltetracarboxylic dianhydride and polyamic acids derived from m-tolidine and diamines comprising 1,3-bis (4-aminophenoxy) benzene Polyimide precursor composition. The method of claim 7, wherein
The diamine is a thermoplastic polyimide precursor composition for a flexible metal laminate comprising at least 30 mol% of m-tolidine and at least 30 mol% of 1,3-bis (4-aminophenoxy) benzene. The method of claim 7, wherein
The acid anhydride is a thermoplastic polyimide precursor composition for a flexible metal laminate comprising at least 70 mol% biphenyltetracarboxylic dianhydride.

Images