WO2016003166A1 - Surface-modified composite silica particles and polyimide film comprising same - Google Patents

Abstract

The present invention relates to surface-modified composite silica particles and a polyimide film comprising the same. The present invention provides: surface-modified composite silica particles which are modified with polysiloxane including a phenyl group to improve compatibility and dispersibility with respect to polymers; and a polymer composite with excellent surface hardness characteristics, manufactured using the particles, especially, a polyimide film.

Description

Surface Modified Composite Silica Particles and Polyimide Film Comprising the Same

The present invention relates to a surface-modified composite silica particles and a polyimide film comprising the same, and more particularly, surface-modified composite silica particles and organic-inorganic composite polyimide including the same to maximize compatibility and dispersibility with the organic polymer. It is about a film.

In general, polyimide (PI) resin is an insoluble and insoluble ultra high heat resistant resin, and has excellent characteristics such as heat oxidation resistance, heat resistance, radiation resistance, low temperature property, chemical resistance, and the like. It is used in a wide range of electronic materials such as advanced materials, insulating coating agents, insulating films, semiconductors, and electrode protective films of TFT-LCDs.

In the case of such a polyimide, a solution of an aromatic dianhydride and an aromatic diamine or an aromatic diisocyanate is used to prepare a polyamic acid derivative, followed by ring closure dehydration at high temperature for imidization. In order to prepare a polyimide resin, pyromellitic dianhydride (PMDA) or biphenyltetracarboxylic dianhydride (BPDA) or the like is used as an aromatic dianhydride component, and oxydianiline (ODA), p is used as an aromatic diamine component. -Phenylene diamine (p-PDA), m-phenylene diamine (m-PDA), methylenedianiline (MDA), bisaminophenylhexafluoropropane (HFDA) and the like are used.

In general, polyimides have high aromatic ring densities and are colored brown or dark, thereby giving transparency to brown and yellow polyimides for applications in advanced materials such as displays and semiconductors. To this end, a linkage group (-O-, -SO2-, -CO-, -CF3CCF3-, etc.) or a relatively free side branch is introduced into the main chain to minimize intermolecular and intramolecular charge transfer complexes to achieve transparency. do.

However, in the case of a film provided with transparency to the polyimide, there is a problem that the heat resistance is reduced due to the introduced functional group. As a result, there is a limit in the application of the material processing field such as a display requiring a high process temperature, and when the mechanical properties are low, tearing occurs in the display manufacturing process, resulting in a drop in product yield.

In order to overcome the drawbacks of the transparent polyimide, it is necessary to include a material of a different form than the polymer, and the most representative example may be Si-based inorganic material. When the filler is made of such an inorganic material is included in the production of the film may increase the runability, or if necessary, there are advantages such as increase in hardness, deformation of optical properties, enhanced heat resistance.

Conventional literature related to the technology of introducing silica into polyimide is disclosed in Korean Patent No. 0652863, which discloses “Silica-polyimide hybrid and its manufacturing method”, “Precursor solution for polyimide / silica composite material, and a manufacturing method thereof. And Korean Patent No. 1246116, which discloses a “polyimide / silica composite material having a low volume shrinkage rate”, and International Publication No. WO2005-080505, which discloses a “polyimide siloxane solution composition”.

However, in the case of most inorganic materials, when a large amount is used, there is a difference in degree depending on the size of the particles and the method of producing the particles, but it shows a limitation in that the haze (haze) is increased due to the aggregation of the inorganic materials during film formation. In addition, the inorganic material itself is not good compatibility with the polymer is poor dispersibility, so to prevent this physical dispersion through a Miller (Mill), a mixer, a high-speed stirrer homogenizer, an ultrasonic disperser. Accordingly, the technology that can further improve the compatibility with the polymer is a situation that is constantly required.

Accordingly, the present invention is intended to improve the heat resistance, transparency and surface hardness of the polyimide film by improving the compatibility and dispersibility of the organic polymer through the surface modification of the silica particles, and further including the surface-modified silica particles.

One embodiment of the present invention is a silica particle whose surface is modified with polysiloxane, the polysiloxane is a polymer of a compound represented by the following formula (1) or a mixture with a compound represented by the following formula (2), containing a phenyl group in the side chain To provide a surface modified composite silica.

[Formula 1]

[Formula 2]

R in Formula 1 or 2 is the same or different from each other selected from the group consisting of H, a halogen atom, a substituted or unsubstituted 1 to 6 alkoxy groups and combinations thereof. In addition, R ₁ is a single bond in which carbon of the benzene ring is directly connected to silicon, an alkylene group having 1 to 8 carbon atoms, an alkenylene group having 3 to 12 carbon atoms, a haloalkenylene group having 3 to 12 carbon atoms, and having 3 to 3 carbon atoms. It is 1 type chosen from the group which consists of an alkynylene group of 8, and its combination.

In a preferred embodiment, the polysiloxane may be a polymer of a mixture of the compound represented by Formula 1 and the compound represented by Formula 2 in a 1: 1 to 1: 5 weight ratio.

The polysiloxane according to one embodiment of the present invention may have a weight average molecular weight of 1,000 to 10,000.

The surface modified composite silica according to one embodiment of the present invention may have an average particle diameter of 0.1 to 50 μm.

The polysiloxane according to one embodiment of the present invention may be 0.1 to 10 parts by weight based on 100 parts by weight of silica particles.

In another embodiment of the present invention, a polyimide resin and silica particles, wherein the silica particles are surface modified composite silica particles whose surface is modified with polysiloxane, the polysiloxane is a compound represented by the following formula (1) or formula (2) The polymer of the mixture with the compound represented by this provides the polyimide film which contains a phenyl group in a side chain.

[Formula 1]

[Formula 2]

R in Formula 1 or 2 is the same or different from each other selected from the group consisting of H, a halogen atom, a substituted or unsubstituted 1 to 6 alkoxy groups and combinations thereof. In addition, R ₁ is a single bond in which carbon of the benzene ring is directly connected to silicon, an alkylene group having 1 to 8 carbon atoms, an alkenylene group having 3 to 12 carbon atoms, a haloalkenylene group having 3 to 12 carbon atoms, and having 3 to 3 carbon atoms. It is 1 type chosen from the group which consists of an alkynylene group of 8, and its combination.

In the film according to an embodiment of the present invention, the polysiloxane may be a polymer of a mixture of the compound represented by Formula 1 and the compound represented by Formula 2 in a 1: 1 to 1: 5 weight ratio.

In the film according to one embodiment of the present invention, the polysiloxane may have a weight average molecular weight of 1,000 to 10,000.

In the film according to one embodiment of the present invention, the surface modified composite silica may have an average particle diameter of 0.1 to 50㎛.

In the film according to the embodiment of the present invention, the surface modified composite silica may be one containing 0.1 to 10 parts by weight of polysiloxane based on 100 parts by weight of silica particles.

The film according to one embodiment of the present invention may include 1 to 10 parts by weight of surface modified composite silica particles based on 100 parts by weight of polyimide resin.

The film according to one embodiment of the present invention may have a haze value of 0.5 to 2.0 based on ASTM D1003. In addition, the surface hardness may be one that satisfies the 2H to 3H standard pencil hardness measurement (load speed 180mm / min load 1kg).

The surface-modified silica particles according to the present invention have a polysiloxane including a phenyl group bonded to the surface of the silica particles, so that the molecular behavior is very similar to a polymer containing a plurality of aromatic rings, such as polyimide, and thus the compatibility with the polymer The dispersibility is improved and at the same time, the improvement of the physical properties by the inorganic material is maximized, thereby making it possible to manufacture a polymer composite having excellent surface strength characteristics, in particular a polyimide film.

According to an aspect of the present invention, polysiloxane is a silica particle whose surface is modified, polysiloxane is a polymer of a compound represented by the following formula (1) or a mixture with a compound represented by the following formula (2), containing a phenyl group in the side chain To provide a surface modified composite silica.

[Formula 1]

[Formula 2]

R in Formula 1 or 2 is the same or different from each other selected from the group consisting of H, a halogen atom, a substituted or unsubstituted 1 to 6 alkoxy groups and combinations thereof. In addition, R ₁ is a single bond in which carbon of the benzene ring is directly connected to silicon, an alkylene group having 1 to 8 carbon atoms, an alkenylene group having 3 to 12 carbon atoms, a haloalkenylene group having 3 to 12 carbon atoms, and having 3 to 3 carbon atoms. It is 1 type chosen from the group which consists of an alkynylene group of 8, and its combination.

Polysiloxane containing a phenyl group in the side chain as a polymer of a compound represented by the formula (1) alone or a mixture with the compound represented by the formula (2), by reacting with the silica particles react with -OH groups present on the surface of the silica bond Can be formed. In particular, as the polysiloxane containing a phenyl group is bonded to the surface of the silica particles, compatibility and dispersibility with a polymer containing a large number of aromatic rings can be improved.

The compound represented by Chemical Formula 1 is not limited thereto, but as an example, diphenylsilandiol (Diphenylsilandiol, DPSD), Diphenyl diethoxy silandiol ((Diphenyldiethoxysilandiol), diphenyl dibutoxy silandiol), etc. are mentioned.

In addition, the compound represented by the formula (2) is not limited, but for example selected from the group consisting of phenyl trimethoxysilane (PTMS, Phenyl trimethoxysilane), phenyl triethoxysilane (PTES, Phenyl triethoxysilane) and mixtures thereof It may be more preferable which one.

According to a preferred embodiment the polysiloxane to modify the surface of the silica particles is a polymer of a mixture of the compound represented by the formula (1) and the compound represented by the formula (2) in a 1: 1 to 1: 5 weight ratio is added The degree of gap / packing between the silica mixtures is more advantageous, which may lead to better surface hardness.

Predictably, the compound represented by the formula (1) may play a role of decreasing yellowness by increasing the spacing of the main chain, and the compound represented by the formula (2) may increase the surface hardness by increasing the packing between silicas. have.

On the other hand, the polysiloxane preferably has a weight average molecular weight of 1,000 to 10,000, in the present invention, the weight average molecular weight is used a device capable of measuring the molecular weight of the polymer, such as Matrix-Assisted Laser Desorption Ionization Mass Spectrometer (MALDS) or GPC Can be measured. When the weight average molecular weight of the polysiloxane is in the above-described range, the polymerization is sufficiently performed, and thus, the hardness improvement effect can be exerted, and it is preferable in terms of preventing the occurrence of turbidity due to entanglement with the polymer in the future.

According to a preferred embodiment of the present invention, the surface modified composite silica has an average particle diameter of 0.1 to 50 μm, even though the surface is modified by polysiloxane groups, since the size of the polysiloxane is very small, it is almost no different from the size of the silica particles before modification. Can be. If the average particle diameter of the surface modified composite silica is within the above range, it may be advantageous to express the effect when applied to the film, and also to control when applying the particle.

The polysiloxane may be advantageous in terms of effective surface modification, the content of which is included in 0.1 to 30 parts by weight based on 100 parts by weight of silica particles, more preferably 1 to 20 parts by weight, most preferably 5 to 10 parts by weight. It may be.

The method for preparing the surface-modified composite silica as described above is not limited thereto. For example, (a) the compound represented by Chemical Formula 1 may be reacted alone, or the compound represented by Chemical Formula 1 and Chemical Formula 2 may be used. Preparing a polysiloxane by reacting the compound in a ratio of 1: 1 to 1: 5; And (b) it can provide a method for producing a surface-modified composite silica comprising the step of reacting by adding the polysiloxane obtained in the step (a) to a solvent in which silica particles are dispersed.

According to a preferred embodiment of the present invention, in the step (a), the reaction is a reaction in which a hydrolysis and condensation reaction occurs in series to form a chain of polysiloxane, and is performed by stirring at a temperature of 70 to 90 ° C. for 5 to 12 hours. It may be. If the temperature is too low or too high, the reaction solvent and the raw material may be easily volatilized, and the reaction may occur sufficiently within this time.

In this case, by-products of alcohol and water are generated as a result of the hydrolysis and condensation polymerization, and by removing them, it is possible to reduce the reverse reaction and induce a forward reaction, thereby controlling the reaction rate. In addition, alcohol and water remaining in the polysiloxane when the reaction is completed may be removed by applying a condition of 80 to 100 ℃ over 10 minutes under reduced pressure, but may not be limited thereto.

According to a preferred embodiment of the present invention, the polysiloxane obtained in step (a) may have a weight average molecular weight of 1,000 to 10,000 for the same reason as described above.

On the other hand, according to a preferred embodiment of the present invention, the silica particles in the step (b) is preferably a particle average particle diameter of 0.1㎛ 50㎛. Silica is formed through hydrolysis and condensation of alkoxy silanes in the presence of water and a catalyst, and any silica particles obtained by conventional synthetic methods are possible. However, when the average particle diameter of the silica particles is less than 0.1㎛, the particles may be too small, there may be a problem in the coating of the polysiloxane, and if the size exceeds 50㎛ silica particles having a particle size within the above range because the particles are difficult to control It may be desirable to use.

According to a preferred embodiment of the present invention, the solvent in which the silica particles are dispersed is water; At least one lower alcohol selected from the group consisting of methanol, ethanol, propanol, isopropanol and butanol; And any one of these mixed solvents, and more preferably water or a mixed solvent of water and a lower alcohol may be used.

According to a preferred embodiment of the present invention, the polysiloxane in the step (b) may be advantageous in terms of effective surface modification of 0.1 to 30 parts by weight based on 100 parts by weight of silica particles, more preferably 1 to 20 parts by weight, most Preferably 5 to 10 parts by weight may be added.

 According to a preferred embodiment of the present invention, the reaction of step (b) is a reaction in which a condensation polymerization takes place between polysiloxane and OH on the surface of hydrolyzed silica particles dispersed in a solvent to form a network, yield of reaction In consideration of this, it is preferable to perform at room temperature for 5 to 10 hours. In addition, the stirring speed may be appropriately adjusted depending on the content of silica and water used.

In particular, in order to further promote the reaction of step (b), according to a preferred embodiment of the present invention, barium oxide, ammonia (NH ₄ OH), potassium hydroxide (KOH), sodium hydroxide (NaOH) and mixtures thereof Step (b) may be carried out under any one of the basic catalysts selected from the group. Although not specifically limited in the present invention, barium hydroxide or ammonia may be preferably used as the basic catalyst.

Furthermore, according to another aspect of the present invention, it is possible to provide a polyimide film including the surface modified composite silica. In this case, the method for preparing a polyimide that can be applied is not limited to the present invention, but may be any conventional method, wherein the surface modified composite silica is dispersed in a solution in which a polyimide resin solid obtained during the polyimide manufacturing process is mixed with a solvent. It is preferable, and it can be physically dispersed using a mill, a mixer, a high speed stirrer, a homogenizer, and an ultrasonic disperser.

According to a preferred embodiment of the present invention, the surface modified composite silica may be included in an amount of 1 to 10 parts by weight based on 100 parts by weight of the polyimide resin solids when the polyimide film is prepared. If the content of the surface-modified composite silica is less than 1 part by weight, the effect of increasing hardness may be insignificant, and the effect may be improved as the content is increased. Can be.

Ultimately, the polyimide film including the surface modified composite silica has a haze value of 0.5 to 2.0 based on ASTM D1003, and a surface hardness of 2H to 3H based on pencil hardness measurement (load speed of 180 mm / min of 1 kg load). In the present invention, the haze value may be measured using a haze meter measuring instrument, and the surface hardness may be measured using an electric pencil hardness meter with Mitsubishi evaluation pencil (UNI) (see Examples below). Characteristics of the polyimide film of the present invention may be due to the surface modified composite silica contained in the polyimide film.

In other words, unlike silica modified with other functional groups, in the case of the composite silica according to the present invention, since the polysiloxane containing a large number of phenyl groups is present on the surface thereof, compatibility with a polymer resin including a plurality of aromatic rings is good. Excellent dispersibility, even if a large amount of particles are present, the film does not become cloudy and maintains a transparent state, and polysiloxanes, which hold the surface and the intermolecular molecules between polymers, increase the hardness, thereby finally including polyimide Haze values and surface hardness in the above range can be implemented in the film.

In the description above and below, the polyimide includes imide bonds in the repeating units of the main chain, which is understood to encompass polyamide-imides containing an acidamide bond (-CONH-) in a portion of the main chain. Will be.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention more specifically, and the present invention is not limited thereto.

Preparation Example 1 Preparation of Silica Particles

300 g of ethanol was added to a 500 ml beaker, and 7 g of tetraethylthoxysilane (TEOS, Si (OC ₂ H ₅ ) ₄ , Sigma-Aldrich), which is a silane material, was added thereto and stirred at room temperature for 30 minutes. Subsequently, 25 g of NH ₄ OH was slowly added to the reactor, followed by stirring at the same temperature for 6 hours. After the reaction was completed, the reaction product was filtered, washed three times with ethanol (50 ml), and then dried in an oven at 40 ° C. for 5 hours under reduced pressure to prepare 5 g of silica particles [SiO ₂ ] having an average particle diameter of 0.2 μm.

The shape and size of the silica particles were observed through TEM (Transmission Electron Microscopy, 200 kV, JEM-2000EX, JEOL, Japan), and Zeta sizer (ELS-8000, Electrophoretic Light Scattering) method.

Otsuka electronics, Japan) to measure the average particle diameter of the particles.

Preparation Example 2 Preparation of Polysiloxane

40 g of diphenylsilandiol, DPSD, (C ₆ H ₅ ) ₂ Si (OH) ₂ , Sigma-Aldrich) and phenyltrimethoxysilane (PTMS, C ₆ H ₅ Si (OCH) ₃ , Sigma-Aldrich) 40g were mixed together through stirring and reacted at 80 ° C. for 10 hours to obtain 60g of polysiloxane having a weight average molecular weight of 5,000.

Here, the weight average molecular weight (unit: g / mol) of the polysiloxane was measured based on PS standard using GPC (Gel Permeation Chromatography, ViscoTek).

Preparation Example 3 Preparation of Surface Modified Composite Silica

After dispersing 5 g of the silica particles obtained in Preparation Example 1 in 300 ml of ethanol, 0.5 g of polysiloxane obtained in Preparation Example 2 and 1 ml of NH ₄ OH were added thereto, and reacted at room temperature for 12 hours. With an average particle diameter of 0.2 Surface modified composite silica particles were prepared. After the reaction was completed, the reaction product was filtered and washed three times with ethanol (50 ml).

In this case, the particle size of the surface modified composite silica was measured by the same method as the method for measuring the average particle diameter of the silica particles.

Example 1

0.1 g (0.1 wt%) of the surface-modified composite silica particles prepared in Preparation Example 3 was added to 100 g of N, N-dimethylacetamide (DMAc), and then dispersed using an ultrasonic dispersion machine of 20 kHz using Qsonica (Misonix). To prepare a mixed composition.

Example 2 and Example 3

The composition was prepared in the same manner as in Example 1, except that 0.5 g (0.5 wt%) and 1 g (1 wt%) of the surface-modified composite silica particles were used.

Comparative Examples 1 to 3

Instead of the surface modified composite silica obtained in Preparation Example 3, a surface (Nippon shokubai, KE-P10, average particle size of 0.15 µm) whose surface is composed of -OH is 0.1 to 100 g of N, N-dimethylacetaamide (DMAc), respectively. The composition of Comparative Examples 1 to 3 was prepared in the same manner as in Example 1, except that g (0.1 wt%), 0.5 g (0.5 wt%), and 1 g (1 wt%) were added.

Haze of the compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were measured and described in Table 1 below. In this case, the haze measurement method was measured based on ASTM D1003 standard using a Haze meter (HM-150 manufactured by Murakaml Color Research Laboratory).

Table 1

division	Example 1	Example 2	Example 3	Comparative Example 1	Comparative Example 2	Comparative Example 3
Surface Modified Composite Silica Particle or Filler Input (wt%)	0.1	0.5	One	0.1	0.5	One
Haze	0.6	1.5	2.0	6.9	14.7	21.6

Haze value can be interpreted that the film is more transparent, haze measurement results, as shown in Table 1, in the case of Examples 1 to 3 in Comparative Examples due to the excellent dispersibility of the surface-modified composite silica particles in the solvent It was confirmed that the haze was significantly lower than 1 to 3.

Example 4

After filling with 716g of N, N-dimethylacetaamide (DMAc) while passing nitrogen through a 1L reactor equipped with a stirrer, a nitrogen injection device, a dropping funnel, a temperature controller and a cooler as a reactor, the temperature of the reactor was adjusted to 25 ° C. 57.64 g (0.18 mol) of TFDB (2,2 ”-bis (trifluoromethyl) biphenyl-4,4” -diamine) was dissolved to maintain this solution at 25 ° C. 23.99 g (0.054 mol) of 6FDA (4,4 '-(hexaflouroisopropyllidene) diphathalic anhydride) and 7.06 g (0.036 mol) of CBDA (cyclobutane-1,2,3,4-tetracarboxylic dianhydride) were added thereto and stirred for a predetermined time. Dissolved and reacted. After the solution was maintained at 15 ° C., 18.27 g (0.09 mol) of terephthaloyl chloride (TPC) was added thereto. The reaction was carried out at 25 ° C. for 12 hours to obtain a solid content of 13 wt% and a viscosity of 860 poise. A solution was obtained.

Subsequently, 34.17 g of pyridine and 44.12 g of acetic anhydride were added to the obtained polyamic acid solution, stirred for 30 minutes, and then stirred at 70 ° C. for 1 hour, cooled to room temperature, precipitated with 20 L of methanol, and the precipitated solid was filtered. The resultant was pulverized and dried in vacuo at 100 ° C. for 6 hours to obtain 95 g of copolymerized polyamide-imide of solid powder.

The copolymerized polyamide-imide of the 95 g solid powder was dissolved in 768 g of N, N-dimethylacetamide (DMAc) to obtain a 11 wt% solution, followed by adding 0.95 g of the surface-modified composite silica obtained in Preparation Example 3. It was.

The solution thus obtained was applied to a stainless plate, cast at 100 μm, dried for 1 hour with a hot air of 150 ° C., 1 hour at 200 ° C., and 30 minutes at 300 ° C., and then slowly cooled to separate from the plate to form a poly of 10 μm. An amide-imide film was obtained. After the final heat treatment was further heat treated at 300 ℃ for 10 minutes.

Example 5

A polyamide-imide film having a thickness of 10 μm was obtained in the same manner as in Example 4, except that the amount of surface-loss composite silica particles was adjusted to 4.75 g.

Comparative Example 4

Prepared in the same manner as in Example 4, to obtain a polyamide-imide film of 10 ㎛ without any surface-modified composite silica.

Comparative Example 5

A 10 μm polyamide-imide film was prepared in the same manner as in Example 4 except that 0.95 g of the filler (Nippon shokubai, KE-P10, average particle size of 0.15 μm) used in the Comparative Example was used instead of the surface-modified composite silica particles. Obtained.

Comparative Example 6

A 10 μm polyamide-imide film was prepared in the same manner as in Example 4 except that 0.95 g of the filler (Nippon shokubai, KE-P10, average particle size of 0.15 μm) used in the Comparative Example was used instead of the surface-modified composite silica particles. Obtained.

The surface hardness of the films prepared in Examples 4 to 5 and Comparative Examples 4 to 6 were measured and described in Table 2. The method of measuring the surface hardness of the film is a Mitsubishi evaluation pencil (UNI) using an electric pencil hardness tester, drawing 50 mm five times at a speed of 180 mm / min at a load of 1 kg, and then measuring the minimum pencil hardness without scratches on the surface. It was.

In addition, the haze of the films prepared in Examples 4 to 5 was measured and described in Table 2 below. In this case, the haze measurement method was measured based on ASTM D1003 standard using a Haze meter (HM-150 manufactured by Murakaml Color Research Laboratory).

TABLE 2

division	Example 4	Example 5	Comparative Example 4	Comparative Example 5	Comparative Example 6
Surface Modified Composite Silica Particles or Filler Charges (wt%) Compared to Polyamide-imide Solid Powders	One	5	0	One	5
Surface hardness	2H	3H	H	H	H
Haze of film (%)	0.7	1.8	Do not measure

As a result of surface hardness measurement, as shown in Table 2, in Comparative Examples 5 and 6, although the filler was added, the hardness was the same as that of Comparative Example 4 (base film), but the polyimide of Examples 4 and 5 Due to the influence of the surface modified composite silica particles according to the invention it was confirmed that the film hardness is significantly improved.

In addition, it was confirmed that the haze of the film itself did not increase significantly even when the silica particles were added as a result of the haze measurement.

Claims (13)

1. Silica particles whose surface is modified with polysiloxane,

   Polysiloxane is a polymer of a compound represented by the following formula (1) or a mixture with a compound represented by the following formula (2), the surface-modified composite silica containing a phenyl group in the side chain.

   [Formula 1]

   

   [Formula 2]

   

   R in Formula 1 or 2 is the same or different from each other selected from the group consisting of H, a halogen atom, a substituted or unsubstituted 1 to 6 alkoxy groups and combinations thereof. In addition, R ₁ is a single bond in which carbon of the benzene ring is directly connected to silicon, an alkylene group having 1 to 8 carbon atoms, an alkenylene group having 3 to 12 carbon atoms, a haloalkenylene group having 3 to 12 carbon atoms, and having 3 to 3 carbon atoms. It is 1 type chosen from the group which consists of an alkynylene group of 8, and its combination.
2. The method of claim 1,

   The polysiloxane is a surface modified composite silica, characterized in that the mixture of a mixture of the compound represented by the formula (1) and the compound represented by the formula (2) in a 1: 1 to 1: 5 weight ratio.
3. The method of claim 1,

   The polysiloxane has a weight average molecular weight of 1,000 to 10,000, characterized in that the surface modified composite silica.
4. The method of claim 1,

   The surface modified composite silica has an average particle diameter of 0.1 to 50㎛ surface modified composite silica.
5. The method of claim 1,

   The polysiloxane has a surface modified composite silica, characterized in that the content of 0.1 to 10 parts by weight based on 100 parts by weight of silica particles.
6. Polyimide resin and silica particles,

   The silica particles are surface modified composite silica particles whose surfaces are modified with polysiloxane, and the polysiloxane is a polymer of a compound represented by the following formula (1) or a mixture with a compound represented by the following formula (2), wherein the side chain contains a phenyl group. , Polyimide film.

   [Formula 1]

   

   [Formula 2]

   

   R in Formula 1 or 2 is the same or different from each other selected from the group consisting of H, a halogen atom, a substituted or unsubstituted 1 to 6 alkoxy groups and combinations thereof. In addition, R ₁ is a single bond in which carbon of the benzene ring is directly connected to silicon, an alkylene group having 1 to 8 carbon atoms, an alkenylene group having 3 to 12 carbon atoms, a haloalkenylene group having 3 to 12 carbon atoms, and having 3 to 3 carbon atoms. It is 1 type chosen from the group which consists of an alkynylene group of 8, and its combination.
7. The method of claim 6,

   The polysiloxane is a polyimide film, characterized in that the mixture of a mixture of the compound represented by the formula (1) and the compound represented by the formula (2) in a 1: 1 to 1: 5 weight ratio.
8. The method of claim 6,

   The polysiloxane has a weight average molecular weight of 1,000 to 10,000, characterized in that the polyimide film.
9. The method of claim 6,

   The surface modified composite silica has an average particle diameter of 0.1 to 50㎛ polyimide film.
10. The method of claim 6,

    The surface-modified composite silica polysiloxane film, characterized in that containing 0.1 to 10 parts by weight of polysiloxane based on 100 parts by weight of silica particles.
11. The method of claim 6,

    A polyimide film comprising 1 to 10 parts by weight of surface modified composite silica particles based on 100 parts by weight of polyimide resin.
12. The method of claim 6,

    The polyimide film has a haze value of 0.5 to 2.0 based on ASTM D1003.
13. The method of claim 6,

    The polyimide film is a polyimide film, characterized in that the surface hardness is 2H to 3H based on pencil hardness measurement (load speed 180mm / min load 1kg).