KR102347633B1 - Polyimide film with improved dielectric properties and manufacturing method thereof - Google Patents

Abstract

The present invention is an imidation reaction of a dianhydride component containing benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA) and a diamine component containing paraphenylene diamine (PPD) a first block obtained by and a dianhydride component including biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA) and a diamine component including m-tolidine. Provided is a polyimide film with improved dielectric properties, including a block copolymer including a second block.

Description

Polyimide film with improved dielectric properties and manufacturing method thereof

The present invention relates to a polyimide film having improved dielectric properties and a method for manufacturing the same.

Polyimide (PI) is a polymer material with the highest level of heat resistance, chemical resistance, electrical insulation, chemical resistance, and weather resistance among organic materials based on an imide ring with excellent chemical stability along with a rigid aromatic main chain. to be.

In particular, due to excellent insulating properties, that is, excellent electrical properties such as low dielectric constant, it is in the spotlight as a high-functional polymer material in the fields of electricity, electronics, and optics.

In recent years, as electronic products become lighter and smaller, thin circuit boards with a high degree of integration and flexibility are being actively developed.

Such a thin circuit board has a structure in which a circuit including a metal foil is formed on a polyimide film that is easy to bend while having excellent heat resistance, low temperature resistance and insulating properties is widely used.

As such a thin circuit board, a flexible metal clad laminate is mainly used, and as an example, a flexible copper clad laminate (FCCL) using a thin copper plate as a metal foil is included. In addition, polyimide is also used as a protective film and insulating film for thin circuit boards.

On the other hand, as various functions are embedded in electronic devices in recent years, fast operation speed and communication speed are required for the electronic devices.

In order to realize high-frequency and high-speed communication, an insulator having a high impedance capable of maintaining electrical insulation even at a high frequency is required. Since the impedance is in inverse proportion to the frequency and dielectric constant (Dk) formed in the insulator, the dielectric constant must be as low as possible to maintain insulation even at high frequencies.

However, in the case of conventional polyimide, the dielectric properties are not excellent enough to maintain sufficient insulation in high-frequency communication.

In addition, it is known that, as the insulator has a low dielectric characteristic, it is possible to reduce the occurrence of undesirable stray capacitance and noise in the thin circuit board, thereby substantially solving the cause of communication delay.

Therefore, polyimide with low dielectric properties is recognized as the most important factor in the performance of thin circuit boards.

In particular, in the case of high-frequency communication, dielectric dissipation inevitably occurs through polyimide. Dielectric dissipation factor (Df) refers to the degree of dissipation of electrical energy in a thin circuit board, and is closely related to the signal propagation delay that determines communication speed. It is recognized as an important factor in the performance of the substrate.

In addition, as the polyimide film contains more moisture, the dielectric constant increases and the dielectric loss factor increases. In the case of a polyimide film, it is suitable as a material for a thin circuit board due to its excellent intrinsic properties, but may be relatively vulnerable to moisture due to polar imide groups, which may deteriorate insulation properties.

Accordingly, there is a need to develop a polyimide film having dielectric properties, particularly low dielectric loss, while maintaining the mechanical properties, thermal properties, and chemical resistance properties unique to polyimide at a certain level.

Republic of Korea Patent Publication No. 10-2015-0069318

Accordingly, in order to solve the above problems, an object of the present invention is to provide a polyimide film having high heat resistance, low dielectric properties and low moisture absorption properties, and a method for manufacturing the same.

Accordingly, it is a practical object of the present invention to provide specific examples thereof.

One embodiment of the present invention for achieving the above object is benzophenone tetracarboxylic dianhydride (3,3',4,4'-Benzophenonetetracarboxylic dianhydride, BTDA) and biphenyltetracarboxylic dianhydride (3,3',4,4'-Biphenyltetracarboxylic dianhydride, BPDA) a dianhydride component containing a first block obtained by imidizing a diamine component containing a component and paraphenylene diamine (p-Phenylenediamine, PPD); and

Imidization reaction of a dianhydride component including biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA) and a diamine component including m-tolidine To provide a polyimide film comprising a block copolymer comprising; a second block obtained by

Based on 100 mol% of the total content of the diamine component of the first block and the second block, the content of m-tolidine is 20 mol% or more and 35 mol% or less, and the content of paraphenylene diamine is 65 mol% or more 80 It may be less than or equal to mole %.

In addition, based on 100 mol% of the total content of the dianhydride component of the first block and the second block, the content of benzophenone tetracarboxylic dianhydride is 10 mol% or more and 20 mol% or less, and biphenyltetracarboxyl The content of lycdianhydride may be 40 mol% or more and 60 mol% or less, and the content of pyromellitic dianhydride may be 20 mol% or more and 45 mol% or less.

The polyimide film may have a dielectric loss factor (Df) of 0.004 or less, a coefficient of thermal expansion (CTE) of 16 ppm/°C or less, and a glass transition temperature (Tg) of 300°C or more.

Another embodiment of the present invention provides a process for preparing a first polyamic acid by (a) polymerizing a first dianhydride component and a first diamine component in an organic solvent;

(b) preparing a second polyamic acid by polymerizing the second dianhydride component and the second diamine component in an organic solvent;

(c) preparing a third polyamic acid by copolymerizing the first polyamic acid and the second polyamic acid in an organic solvent; and

(d) forming a film of the precursor composition containing the third polyamic acid on a support, and then imidizing;

The first dianhydride component includes benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA),

The second dianhydride component includes biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride,

The first diamine component comprises paraphenylene diamine (PPD),

The second diamine component provides a method of manufacturing a polyimide film including m-tolidine.

As described above, the present invention provides a polyimide film having high heat resistance, low dielectric properties, and low moisture absorption characteristics through a polyimide film composed of specific components and specific composition ratios and a method for manufacturing the same. It can be usefully applied to various fields, particularly electronic components such as flexible metal clad laminates.

Hereinafter, embodiments of the invention will be described in more detail in the order of "polyimide film" and "method for producing polyimide film" according to the invention.

Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

Accordingly, since the configuration of the embodiments described in the present specification is only one of the most preferred embodiments of the present invention and does not represent all the technical spirit of the present invention, various equivalents and modifications that can be substituted for them at the time of the present application It should be understood that examples may exist.

In this specification, the singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as "comprise", "comprising" or "have" are intended to designate the existence of an embodied feature, number, step, element, or a combination thereof, but one or more other features or It should be understood that the existence or addition of numbers, steps, elements, or combinations thereof, is not precluded in advance.

Where an amount, concentration, or other value or parameter is given herein as a range, a preferred range, or a recitation of a preferred upper value and a lower preferred value, any pair of any upper limit of the range or It is to be understood that the preferred values and any lower range limits or all ranges formed by the preferred values are specifically disclosed.

When a range of numerical values is recited herein, the range is intended to include the endpoints and all integers and fractions within the range, unless otherwise stated. It is intended that the scope of the invention not be limited to the particular values recited when defining the ranges.

As used herein, “dianhydride” is intended to include precursors or derivatives thereof, which may not technically be dianhydride acids, but will nevertheless react with a diamine to form a polyamic acid, which in turn is a polyamic acid can be converted into mids.

As used herein, "diamine" is intended to include precursors or derivatives thereof, which may not technically be diamines, but will nevertheless react with dianhydrides to form polyamic acids, which in turn are polyamic acids. can be converted into mids.

The polyimide film according to the present invention is a diamine containing a dianhydride component including benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA) and paraphenylene diamine (PPD) a first block obtained by imidizing a component; and

A preparation obtained by imidizing a dianhydride component containing biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA) and a diamine component containing m-tolidine It is a polyimide film comprising a block copolymer comprising two blocks.

Based on 100 mol% of the total content of the diamine component of the first block and the second block, the content of m-tolidine is 20 mol% or more and 35 mol% or less, and the content of paraphenylene diamine is 65 mol% or more 80 It may be less than or equal to mole %.

Especially. The content of m-tolidine is preferably 20 mol% or more and 30 mol% or less. Since m-tolidine has a particularly hydrophobic methyl group, it contributes to the low moisture absorption properties of the polyimide film.

In addition, the content of benzophenone tetracarboxylic dianhydride is 10 mol% or more and 20 mol% or less, based on 100 mol% of the total content of the dianhydride component of the first block and the second block, and biphenyltetracarboxyl The content of lycdianhydride may be 40 mol% or more and 60 mol% or less, and the content of pyromellitic dianhydride may be 20 mol% or more and 45 mol% or less.

In particular, it is preferable that the content of the benzophenone tetracarboxylic dianhydride is 15 mol% or more and 20 mol% or less.

The polyimide chain derived from the biphenyltetracarboxylic dianhydride of the present invention has a structure called a charge transfer complex (CTC), that is, an electron donor and an electron acceptor. It has a regular linear structure positioned close to each other, and the intermolecular interaction is strengthened.

In addition, benzophenone tetracarboxylic dianhydride having a carbonyl group contributes to the expression of CTC like biphenyl tetracarboxylic dianhydride.

Since such a structure has an effect of preventing hydrogen bonding with moisture, it is possible to maximize the effect of lowering the hygroscopicity of the polyimide film by affecting the lowering of the moisture absorption.

In one specific example, the dianhydride component may additionally include pyromellitic dianhydride. The pyromellitic dianhydride is a dianhydride component having a relatively rigid structure, and is preferable in that it can impart appropriate elasticity to the polyimide film.

In order for the polyimide film to simultaneously satisfy appropriate elasticity and moisture absorption, the content ratio of dianhydride is particularly important. For example, as the content ratio of biphenyltetracarboxylic dianhydride decreases, it becomes difficult to expect a low moisture absorption rate due to the CTC structure.

In addition, biphenyltetracarboxylic dianhydride and benzophenonetetracarboxylic dianhydride contain two benzene rings corresponding to the aromatic moiety, whereas pyromellitic dianhydride has a benzene ring corresponding to the aromatic moiety. includes one.

An increase in the content of pyromellitic dianhydride in the dianhydride component can be understood as an increase in the imide group in the molecule based on the same molecular weight, which is an image derived from the pyromellitic dianhydride in the polyimide polymer chain. It can be understood that the ratio of the group is relatively increased compared to the imide group derived from biphenyltetracarboxylic dianhydride and benzophenonetetracarboxylic dianhydride.

That is, the increase in the pyromellitic dianhydride content can be seen as a relative increase in the imide group for the entire polyimide film, and thus it is difficult to expect a low moisture absorption rate.

Conversely, when the content ratio of pyromellitic dianhydride is reduced, a component having a relatively rigid structure is decreased, and thus the elasticity of the polyimide film may be lowered to a desired level or less.

For this reason, when the content of biphenyltetracarboxylic dianhydride and benzophenone tetracarboxylic dianhydride exceeds the above range or the content of pyromellitic dianhydride is less than the above range, Mechanical properties deteriorate, and heat resistance at an appropriate level for manufacturing a flexible metal clad laminate cannot be secured.

Conversely, when the content of biphenyltetracarboxylic dianhydride and benzophenone tetracarboxylic dianhydride is less than the above range, or the content of pyromellitic dianhydride exceeds the above range, an appropriate level of dielectric It is not preferable because it is difficult to achieve the constant, dielectric loss factor and moisture absorption factor.

The polyimide film may have a dielectric loss factor (Df) of 0.004 or less, a coefficient of thermal expansion (CTE) of 16 ppm/°C or less, and a glass transition temperature (Tg) of 300°C or more.

In this regard, in the case of a polyimide film that satisfies all of the dielectric loss factor (Df), glass transition temperature, and coefficient of thermal expansion, it can be used as an insulating film for flexible metal clad laminates, and the manufactured flexible metal clad laminates transmit signals at a high frequency of 10 GHz or higher. Even if it is used as an electrical signal transmission circuit for transmitting, its insulation stability can be secured, and a signal transmission delay can also be minimized.

The polyimide film having all of the above conditions is a novel polyimide film not known until now, and the dielectric loss factor (Df) will be described in detail below.

<Dielectric loss rate>

"Dielectric loss factor" means the force dissipated by a dielectric (or insulator) when the friction of the molecules interferes with the molecular motion caused by an alternating electric field.

The value of the dielectric loss factor is commonly used as an index indicating the ease of dissipation of electric charge (dielectric loss). The higher the dielectric loss factor, the easier it is to dissipate the charge. have. That is, since the dielectric loss factor is a measure of power loss, the lower the dielectric loss factor, the faster the communication speed can be maintained while signal transmission delay due to power loss is alleviated.

This is strongly required for the polyimide film, which is an insulating film, and the polyimide film according to the present invention may have a dielectric loss factor of 0.004 or less under a very high frequency of 10 GHz.

In the present invention, the preparation of the polyamic acid is, for example,

(1) a method in which the whole amount of the diamine component is placed in a solvent, and then the dianhydride component is added so as to be substantially equimolar with the diamine component, followed by polymerization;

(2) a method in which the entire amount of the dianhydride component is placed in a solvent, and then the diamine component is added so as to be substantially equimolar with the dianhydride component and polymerized;

(3) After putting some of the diamine components in the solvent, mixing some of the dianhydride components with respect to the reaction components in a ratio of about 95 to 105 mol%, then adding the remaining diamine components and successively with the remaining dianhydride acid a method of polymerization by adding a component so that the diamine component and the dianhydride component are substantially equimolar;

(4) After putting the dianhydride component in the solvent, mixing some components of the diamine compound in a ratio of 95 to 105 mol% with respect to the reaction component, adding another dianhydride component, and then adding the remaining diamine components, a method of polymerization such that the diamine component and the dianhydride component are substantially equimolar;

(5) reacting some diamine component and some dianhydride component in an excess of any one in a solvent to form a first composition, and reacting some diamine component and some dianhydride component in another solvent so that any one is excessive 2 After forming the composition, the first and second compositions are mixed and polymerization is completed. At this time, when the diamine component is excessive when the first composition is formed, in the second composition, the dianhydride component is used in excess And, when the dianhydride component in the first composition is excessive, in the second composition, the diamine component is in excess, and the first and second compositions are mixed and the total diamine component and the dianhydride component used in these reactions are substantially the same The method of superposing|polymerizing so that it may become molar, etc. are mentioned.

However, the polymerization method is not limited to the above examples, and any known method may be used for the preparation of the first to third polyamic acids.

In one specific example, the method for producing a polyimide film according to the present invention,

(a) preparing a first polyamic acid by polymerizing the first dianhydride component and the first diamine component in an organic solvent;

(b) preparing a second polyamic acid by polymerizing the second dianhydride component and the second diamine component in an organic solvent;

(c) preparing a third polyamic acid by copolymerizing the first polyamic acid and the second polyamic acid in an organic solvent; and

(d) forming a film of the precursor composition containing the third polyamic acid on a support, and then imidizing;

The first dianhydride component includes benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA),

The second dianhydride component includes biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride,

The first diamine component may include paraphenylene diamine (PPD), and the second diamine component may include m-tolidine.

Based on 100 mol% of the total content of the first diamine component and the second diamine component, the content of m-tolidine is 20 mol% or more and 35 mol% or less, and the content of paraphenylene diamine is 65 mol% or more and 80 mol% % or less.

In addition, the content of benzophenone tetracarboxylic dianhydride is 10 mol% or more and 20 mol% or less, based on 100 mol% of the total content of the first dianhydride acid and the second dianhydride component, and biphenyltetracarboxylic The content of dianhydride may be 40 mol% or more and 60 mol% or less, and the content of pyromellitic dianhydride may be 20 mol% or more and 45 mol% or less.

In the present invention, the polymerization method of the polyamic acid as described above can be defined as a random polymerization method, and the polyimide film prepared from the polyamic acid of the present invention prepared by the above process has a dielectric loss factor (Df) and It can be preferably applied in terms of maximizing the effect of the present invention for lowering the moisture absorption.

However, in the polymerization method, since the length of the repeating unit in the above-described polymer chain is relatively short, there may be a limit in exhibiting excellent properties of the polyimide chain derived from the dianhydride component. Accordingly, the polymerization method of the polyamic acid that can be particularly preferably used in the present invention may be a block polymerization method.

On the other hand, the solvent for synthesize|combining a polyamic acid is not specifically limited, Any solvent can be used as long as it is a solvent in which a polyamic acid is dissolved, It is preferable that it is an amide type solvent.

Specifically, the solvent may be an organic polar solvent, specifically an aprotic polar solvent, for example, N,N-dimethylformamide (DMF), N,N- It may be at least one selected from the group consisting of dimethylacetamide, N-methyl-pyrrolidone (NMP), gamma butyrolactone (GBL), and Diglyme, but is not limited thereto. It can be used in combination of two or more types.

In one example, as the solvent, N,N-dimethylformamide and N,N-dimethylacetamide may be particularly preferably used.

In addition, in the polyamic acid manufacturing process, a filler may be added for the purpose of improving various properties of the film, such as slidability, thermal conductivity, corona resistance, and loop hardness. The filler to be added is not particularly limited, but preferred examples thereof include silica, titanium oxide, alumina, silicon nitride, boron nitride, calcium hydrogen phosphate, calcium phosphate, mica, and the like.

The particle size of the filler is not particularly limited, and may be determined according to the characteristics of the film to be modified and the type of filler to be added. Generally, the average particle diameter is 0.05 to 100 μm, preferably 0.1 to 75 μm, more preferably 0.1 to 50 μm, particularly preferably 0.1 to 25 μm.

When the particle size is less than this range, the modifying effect becomes difficult to appear, and when the particle size exceeds this range, the surface properties may be greatly impaired or the mechanical properties may be greatly reduced.

Moreover, it is not specifically limited also about the addition amount of a filler, What is necessary is just to determine by the film characteristic to be modified|reformed, a filler particle diameter, etc. In general, the added amount of the filler is 0.01 to 100 parts by weight, preferably 0.01 to 90 parts by weight, and more preferably 0.02 to 80 parts by weight based on 100 parts by weight of polyimide.

When the filler addition amount is less than this range, the modifying effect by the filler is difficult to appear, and when it exceeds this range, the mechanical properties of the film may be greatly impaired. The method of adding a filler is not specifically limited, Any well-known method can also be used.

In the manufacturing method of the present invention, the polyimide film may be prepared by thermal imidization and chemical imidization.

Also, it may be prepared by a complex imidization method in which thermal imidization and chemical imidization are combined.

The thermal imidization method is a method in which a chemical catalyst is excluded and the imidization reaction is induced by a heat source such as hot air or an infrared dryer.

The thermal imidization method can imidize the amic acid group present in the gel film by heat-treating the gel film at a variable temperature in the range of 100 to 600 ° C., specifically 200 to 500 ° C., more specifically, The amic acid group present in the gel film can be imidized by heat treatment at 300 to 500 °C.

However, in the process of forming the gel film, some of the amic acid (about 0.1 mol% to 10 mol%) may be imidized, and for this purpose, the polyamic acid composition is dried at a variable temperature in the range of 50 ℃ to 200 ℃. and may also be included in the scope of the thermal imidization method.

In the case of chemical imidization, a polyimide film may be prepared by using a dehydrating agent and an imidizing agent according to a method known in the art.

As an example of the complex imidization method, after adding a dehydrating agent and an imidizing agent to a polyamic acid solution, heating at 80 to 200° C., preferably 100 to 180° C., partially curing and drying, at 200 to 400° C. for 5 to 400 seconds A polyimide film can be manufactured by heating.

The polyimide film of the present invention manufactured according to the above manufacturing method has a dielectric loss factor (Df) of 0.004 or less, a coefficient of thermal expansion (CTE) of 15 ppm/°C or less, and a glass transition temperature (Tg) of 340° C. or more. can

The present invention provides a multilayer film including the above-described polyimide film and a thermoplastic resin layer, and a flexible metal clad laminate including the above-described polyimide film and an electrically conductive metal foil.

As the thermoplastic resin layer, for example, a thermoplastic polyimide resin layer or the like may be applied.

The metal foil to be used is not particularly limited, but when the flexible metal foil laminate of the present invention is used for electronic devices or electrical devices, for example, copper or copper alloy, stainless steel or its alloy, nickel or nickel alloy (42 alloy). also included), may be a metal foil comprising aluminum or an aluminum alloy.

In general flexible metal clad laminates, copper foils such as rolled copper foils and electrolytic copper foils are often used, and they can be preferably used in the present invention as well. Moreover, the antirust layer, the heat-resistant layer, or the adhesive layer may be apply|coated on the surface of these metal foils.

In the present invention, the thickness of the metal foil is not particularly limited, and may have a thickness capable of exhibiting a sufficient function according to its use.

In the flexible metal clad laminate according to the present invention, a metal foil is laminated on one surface of the polyimide film, or an adhesive layer containing a thermoplastic polyimide is added to one surface of the polyimide film, and the metal foil is attached to the adhesive layer. It may have a laminated structure.

The present invention also provides an electronic component including the flexible metal clad laminate as an electrical signal transmission circuit. The electrical signal transmission circuit may be an electronic component that transmits a signal at a high frequency of at least 2 GHz, specifically, a high frequency of at least 5 GHz, and more specifically, a high frequency of at least 10 GHz.

The electronic component may be, for example, a communication circuit for a portable terminal, a communication circuit for a computer, or a communication circuit for aerospace, but is not limited thereto.

Hereinafter, through specific examples of the invention, the operation and effect of the invention will be described in more detail. However, these embodiments are merely presented as an example of the invention, and the scope of the invention is not defined thereby.

<Example 1>

DMF is introduced while nitrogen is injected into a 500 ml reactor equipped with a stirrer and nitrogen injection/discharge tube, and the temperature of the reactor is set to 30° C. or lower. Then, paraphenylene diamine as a diamine component and benzophenone tetracarboxylic It is confirmed that dianhydride and biphenyltetracarboxylic dianhydride are added and completely dissolved. Stirring was continued for 120 minutes while raising the temperature to 40° C. under a nitrogen atmosphere, and then, a first polyamic acid having a viscosity of 200,000 cP at 23° C. was prepared.

NMP was introduced while nitrogen was injected into a 500 ml reactor equipped with a stirrer and nitrogen injection/discharge tube, and the temperature of the reactor was set at 30° C., m-tolidine as a diamine component, and biphenyltetracarboxylic dian Confirm that the hydride and pyromellitic dianhydride are completely dissolved. A second polyamic acid having a viscosity of 200,000 cP at 23°C was prepared after stirring was continued for 120 minutes while heating and raising the temperature to 40°C in a nitrogen atmosphere.

Then, the temperature of the first polyamic acid and the second polyamic acid was raised to 40° C. under a nitrogen atmosphere and stirring was continued for 120 minutes while heating, and then the final viscosity at 23° C. was 200,000 cP, and the diamine component and dianhydride acid A third polyamic acid including the components as shown in Table 1 was prepared.

The third polyamic acid prepared above was bubbled through a high-speed rotation of 1,500 rpm or more. Thereafter, the defoamed polyimide precursor composition was applied to the glass substrate using a spin coater. Thereafter, the gel film was prepared by drying under a nitrogen atmosphere and at a temperature of 120° C. for 30 minutes, and the temperature of the gel film was raised to 450° C. at a rate of 2° C./min, heat-treated at 450° C. for 60 minutes, and up to 30° C. A polyimide film was obtained by cooling at a rate of 2° C./min.

Thereafter, the polyimide film was peeled off the glass substrate by dipping in distilled water. The thickness of the prepared polyimide film was 15 μm. The thickness of the prepared polyimide film was measured using an electric film thickness tester manufactured by Anritsu.

<Examples 2 to 4 and Comparative Examples 1,2>

In Example 1, a polyimide film was prepared in the same manner as in Example 1, except that the components and their contents were respectively changed as shown in Table 1 below.

dianhydride component
(mole%) diamine component
(mole%) Polyamic acid polymerization method BPDA
(mole%) BTDA
(mole%) PMDA
(mole%) m-Tolidine
(mole%) PPD
(mole%) Example 1 40 17 43 30 70 block polymerization Example 2 45 17 38 30 70 block polymerization Example 3 55 17 28 30 70 block polymerization Example 4 60 17 23 30 70 block polymerization Comparative Example 1 35 17 48 30 70 block polymerization Comparative Example 2 65 17 18 30 70 block polymerization

< Experimental example 1>Evaluation of dielectric loss factor, coefficient of thermal expansion and glass transition temperature

For the polyimide films prepared in Examples 1 to 4 and Comparative Examples 1 and 2, respectively, dielectric loss coefficient, thermal expansion coefficient, and glass transition temperature were measured, and the results are shown in Table 2 below.

(1) Measurement of dielectric loss factor

The dielectric loss factor (Df) was measured by leaving the flexible metal clad laminate for 72 hours using an Agilent 4294A ohmmeter.

(2) Measurement of coefficient of thermal expansion

The coefficient of thermal expansion (CTE) was measured using a Q400 thermomechanical analyzer from TA, and after cutting a polyimide film to 4 mm in width and 20 mm in length, while applying a tension of 0.05 N under a nitrogen atmosphere, 10 °C/min After raising the temperature from room temperature to 300°C at a rate of

(3) Glass transition temperature measurement

The glass transition temperature (T _g ) was obtained by obtaining the loss modulus and storage modulus of each film using DMA, and the inflection point was measured as the glass transition temperature in their tangent graph.

Df CTE
(ppm/℃) Tg
(℃) Example 1 0.0039 8.3 310 Example 2 0.0035 11.3 306 Example 3 0.0028 13.5 303 Example 4 0.0027 15.2 301 Comparative Example 1 0.0044 3.4 358 Comparative Example 2 0.0027 16.5 287

As shown in Table 2, it can be confirmed that the polyimide film prepared according to an embodiment of the present invention exhibits a remarkably low dielectric loss factor of 0.004 or less, as well as a coefficient of thermal expansion and a desired glass transition temperature.

These results are achieved by the components and composition ratios specified herein, and it can be seen that the content of each component plays a decisive role.

On the other hand, the Examples compared with the polyimide films of Comparative Examples 1 and 2 having different components are difficult to be used in electronic components in which signals are transmitted at high frequency in giga units in one or more aspects of dielectric loss factor, thermal expansion coefficient, and glass transition temperature. It can be expected.

Although described above with reference to the embodiments of the present invention, those of ordinary skill in the art to which the present invention pertains will be able to make various applications and modifications within the scope of the present invention based on the above content.

Claims (11)

A preparation obtained by imidizing a dianhydride component containing benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA) with a diamine component containing paraphenylene diamine (PPD). 1 block; and
A preparation obtained by imidizing a dianhydride component containing biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride (PMDA) and a diamine component containing m-tolidine 2 blocks; including a block copolymer comprising
The content of benzophenonetetracarboxylic dianhydride is 10 mol% or more and 20 mol% or less, based on 100 mol% of the total content of the dianhydride component of the first block and the second block, and biphenyltetracarboxylic dian The content of hydride is 40 mol% or more and 60 mol% or less, and the content of pyromellitic dianhydride is 20 mol% or more and 45 mol% or less,
The dielectric loss factor (Df) is 0.004 or less,
The coefficient of thermal expansion (CTE) is 16 ppm/℃ or less,
The glass transition temperature (Tg) is 300 ℃ or more,
polyimide film. According to claim 1,
Based on 100 mol% of the total content of the diamine component of the first block and the second block, the content of m-tolidine is 20 mol% or more and 35 mol% or less, and the content of paraphenylene diamine is 65 mol% or more 80 less than or equal to mole %,
polyimide film. delete delete (a) preparing a first polyamic acid by polymerizing the first dianhydride component and the first diamine component in an organic solvent;
(b) preparing a second polyamic acid by polymerizing the second dianhydride component and the second diamine component in an organic solvent;
(c) preparing a third polyamic acid by copolymerizing the first polyamic acid and the second polyamic acid in an organic solvent; and
(d) forming a film of the precursor composition containing the third polyamic acid on a support, and then imidizing;
The first dianhydride component includes benzophenonetetracarboxylic dianhydride (BTDA) and biphenyltetracarboxylic dianhydride (BPDA),
The second dianhydride component includes biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic dianhydride,
The first diamine component comprises paraphenylene diamine (PPD),
The second diamine component includes m-tolidine,
The content of benzophenonetetracarboxylic dianhydride is 10 mol% or more and 20 mol% or less, based on 100 mol% of the total content of the first dianhydride and the second dianhydride component, and biphenyltetracarboxylic dianhydride The content of the ride is 40 mol% or more and 60 mol% or less, and the content of pyromellitic dianhydride is 20 mol% or more and 45 mol% or less,
The dielectric loss factor (Df) is 0.004 or less,
The coefficient of thermal expansion (CTE) is 16 ppm/℃ or less,
The glass transition temperature (Tg) is 300 ℃ or more,
A method for producing a polyimide film. 6. The method of claim 5,
Based on 100 mol% of the total content of the first diamine component and the second diamine component, the content of m-tolidine is 20 mol% or more and 35 mol% or less, and the content of paraphenylene diamine is 65 mol% or more and 80 mol% % or less,
A method for producing a polyimide film. delete delete A multilayer film comprising the polyimide film according to claim 1 or 2 and a thermoplastic resin layer. A flexible metal clad laminate comprising the polyimide film according to claim 1 or 2 and an electrically conductive metal foil. An electronic component comprising the flexible metal clad laminate according to claim 10 .