KR20180055695A - Polystylene-based film and multilayer film - Google Patents

Abstract

Provided is a polystyrene-based film ensuring low costs for ginning. To this end, the polystyrene-based film comprises a syndiotactic polystyrene-based resin and a spherical filler, and is biaxially oriented, while having gloss of 30% or less, surface roughness (Ra) of 0.8 μm or more, and tensile elongation of 15% or more. Preferably, the spherical filler is amorphous silica, more preferably the spherical filler is fused silica.

Description

POLYSTYLENE-BASED FILM AND MULTILAYER FILM < RTI ID = 0.0 >

The present invention relates to a biaxially oriented syndiotactic polystyrene type film having a roughened surface. The present invention also relates to a multilayer film having a biaxially oriented syndiotactic polystyrene-based resin layer having a roughened surface on the outermost layer.

The syndiotactic polystyrene (SPS) based resin is excellent in heat resistance and chemical resistance, and therefore has been widely used as a molded product or a film in various fields. As one of such applications, when a printed substrate, a ceramic electronic component, a semiconductor package, and various other resin molded articles are produced by using the characteristics of an SPS resin that has a low surface tension and a low wettability, It has been studied to use a biaxially oriented SPS-based film as a release film for preventing adhesion of a molding material. Patent Literatures 1 to 3 disclose a single-layer or multilayer release film using an SPS-based resin.

Further, in such a release film, in order to give a matte tone DML appearance to the surface of the molded article, there is a case where the release film is roughened and the surface roughness is transferred to the molded article. Patent Documents 4 and 5 disclose a method of transferring unevenness of a roll surface to a film surface by passing a biaxially oriented SPS film between a roll having a matte tone surface and another roll while heating and pressing the film, . Patent Document 6 describes an SPS-based film which is roughened by melting and kneading an SPS-based resin and polycarbonate into a film and biaxially stretching it. Patent Document 7 describes an SPS-based film which is roughened by melting and kneading an SPS-based resin and a styrenic thermoplastic elastomer into a film and biaxially stretching it.

Japanese Patent Application Laid-Open No. 2001-168117 Japanese Patent Application Laid-Open No. 2001-310428 Japanese Patent Application Laid-Open No. 2014-226785 Japanese Patent Application Laid-Open No. 2013-216779 Japanese Patent Application Laid-Open No. 2013-215989 Japanese Laid-Open Patent Publication No. 2016-000467 Japanese Laid-Open Patent Publication No. 2011-000468

In the method of roughening by roll transfer as described in Patent Documents 4 and 5, a roughening process is required separately from the orientation process of the film, and there is room for improvement in terms of production cost.

On the other hand, in the method described in Patent Documents 6 and 7 in which SPS and another resin are mixed and biaxially stretched, the manufacturing cost can be reduced. However, since the surface irregularities as large as the roll transfer method can not be obtained, the texture is slightly different even if it has the same gloss as the roll transfer system, and some users have been required to adjust the texture by increasing the surface irregularities.

In addition, the present inventors have tried to roughen the surface of an SPS film by mixing a filler in the past. At that time, however, the film strength remarkably decreases due to the mixing of the filler, so that the addition amount of the filler is limited and it is difficult to make the film matte tone stronger (paragraph 0009 of Patent Document 4).

The present invention has been made in view of the above, and an object thereof is to provide a biaxially oriented SPS-based film whose surface is roughened, and which has a large surface unevenness and is more inexpensive.

In order to solve the above problem, in the present invention, a spherical filler is blended in the SPS resin and biaxially oriented to roughen the surface.

Specifically, the polystyrene-based film of the present invention contains a syndiotactic polystyrene-based resin and a spherical filler and is biaxially oriented, and has a gloss of 30% or less, a surface roughness (Ra) of 0.8 탆 or more, a tensile elongation of 15 %.

Here, the term "glossiness" means that the glossiness is 60 deg., Gs (60 deg.) Specified in JIS Z8741: 1997. The glossiness in the present invention is an average value of values in the longitudinal direction (MD) and the lateral direction (TD). Surface roughness (Ra) refers to the arithmetic mean roughness (Ra) specified in JIS B0601: 1994. Tensile elongation is defined as tensile failure (without yield) or tensile failure (with yield) by tensile test specified in JIS K7127: 1999 (specimen type 2, test speed 200 mm / min) It says. The film tensile elongation of the present invention is 15% or more in each of the longitudinal direction (MD) and the transverse direction (TD).

With this configuration, a polystyrene-based film having surface irregularity and gloss equivalent to conventional roll transfer systems can be obtained without excessively damaging the mechanical properties of the film.

Preferably, the spherical filler is amorphous silica, more preferably the spherical filler is fused silica.

Preferably, the spherical filler has a maximum diameter of less than the thickness of the polystyrene-based film and a median diameter (d50) of 6% or more of the thickness of the polystyrene-based film. Here, the median diameter (d50) is a value on a volume basis.

The amount of the spherical filler is preferably 5 parts by weight or more and 20 parts by weight or less based on 100 parts by weight of the resin component.

The multilayer film of the present invention is a multilayer film comprising a first surface constituting a first surface having a gloss of 30% or less and a surface roughness (Ra) of 0.8 탆 or more and containing a syndiotactic polystyrene resin and a spherical filler, And at least one resin layer provided on the opposite side of the first surface of the first layer. And, when the tensile elongation is 15% or more and the tensile strain is less than 15%, the first layer is not broken.

With this constitution, a multilayer film having the surface unevenness and gloss equivalent to those of the conventional roll transfer method on the first surface can be obtained. Further, it is possible to realize the property required for the multilayer film in a manner different from that of the first layer, and it becomes easier to optimize the texture of the surface irregularities and the appearance of the first layer.

Preferably, the resin layer adjacent to the first layer is made of the same syndiotactic polystyrene resin as the first layer, and the content of the spherical filler is smaller than that of the first layer or does not include a spherical filler.

Preferably, the second surface opposite to the first surface is constituted by an antistatic layer.

According to the present invention, since the syndiotactic polystyrene-based film or the syndiotactic polystyrene-based resin layer is roughened by compounding biaxial orientation of the filler, a film having a roughened surface can be obtained at a lower cost than a conventional roll transfer system . In addition, since the filler is spherical, a reduction in the mechanical properties of the film is small and a polystyrene-based monolayer film or multilayer film having surface roughness and gloss equivalent to those of the conventional roll transfer system is obtained while maintaining sufficient tensile elongation .

1 is an example of a cross-sectional view of a multilayer film according to a second embodiment of the present invention.
2 is another example of a cross-sectional view of a multilayer film according to a second embodiment of the present invention.

The polystyrene-based film of the first embodiment of the present invention is a single-layer release film in which a spherical filler is mixed with a syndiotactic polystyrene (SPS) resin and the surface is roughened by biaxial stretching.

First, the composition of the film of this embodiment will be described.

The SPS resin is a styrenic polymer having a syndiotactic structure. The syndiotactic structure means a stereostructure in which the stereochemical structure is a syndiotactic structure, that is, a phenyl group or a substituted phenyl group in which the side chain is alternately located in the opposite direction to the main chain formed from a carbon-carbon bond.

The degree of stereoregularity of the SPS resin (tacticity) can be quantitatively determined by nuclear magnetic resonance (13C-NMR) method using isotopic carbon. The tacticity of the SPS resin measured by the 13 C-NMR method is a chain consisting of several monomer units, for example, triad in the case of two, triad in the case of three, pentad in the case of five, , And a ratio of a syndiotactic compound (such as racidadec) in which the configuration of the constitutional unit is reversed. The SPS resin in the present invention is usually at least 75%, preferably at least 85%, or at least 60%, preferably at least 75%, preferably at least 80% To 30% or more, preferably 50% or more, of syndiotactic polymer.

Examples of the styrenic polymer as the SPS resin include polystyrene, poly (alkylstyrene), poly (halogenated styrene), poly (halogenated alkylstyrene), poly (alkoxystyrene), poly (vinylbenzoic acid ester) A mixture thereof, or a copolymer containing these as a main component. Examples of the poly (alkylstyrene) include poly (methylstyrene), poly (ethylstyrene), poly (isopropylstyrene), poly (tertiary butylstyrene), poly (phenylstyrene), poly (vinylnaphthalene) And the like. Examples of poly (halogenated styrene) include poly (chlorostyrene), poly (bromostyrene), and poly (fluorostyrene). Examples of poly (halogenated alkylstyrene) include poly (chloromethylstyrene). Examples of the poly (alkoxystyrene) include poly (methoxystyrene) and poly (ethoxystyrene).

The weight average molecular weight of the SPS resin constituting the plastic film according to the present invention is 10,000 to 3,000,000, preferably 30,000 to 1,500,000, and particularly preferably 50,000 to 500,000. The glass transition temperature of the SPS resin is 60 to 140 占 폚, preferably 70 to 130 占 폚. The melting point of the SPS-based resin is 200 to 320 占 폚, preferably 220 to 280 占 폚. In the present specification, the glass transition temperature and melting point of the resin are values measured according to JIS K7121.

The SPS-based resin contained in the film of the present embodiment may be a mixture of two or more different SPS-based resins.

The film of the present embodiment may contain other resins as far as they do not adversely affect practical properties such as heat resistance, chemical resistance and low surface tension, which are characteristic of SPS-based films. In this case, the content ratio of the SPS resin to the total resin component in the film is preferably 50% by weight or more, more preferably 60% by weight or more, and particularly preferably 75% by weight or more.

For example, the film of the present embodiment may contain a styrene-based thermoplastic elastomer (TPS). TPS is a thermoplastic elastomer (TPE) in which the hard segment is made of polystyrene, so that when it is blended with an SPS-based film, appearance defects and the like are hardly produced. By combining TPS, flexibility of the film is improved. Further, as described in Patent Document 7, SPS-based films obtained by mixing TPS with SPS-based resin and biaxial mixing are obtained, and therefore, in this embodiment, the effect of the spherical filler and the matte tone of the film Can be made stronger.

When TPS is blended, it is preferable to use hydrogenated one. As a result, the heat resistance of the TSP is improved, and unexpected reactions can be prevented from occurring in the melting and extrusion process of the SPS resin which is carried out at a high temperature.

Examples of the hydrogenated TPS include polystyrene-poly (ethylene / butylene) -polystyrene (TPS-SEBS), polystyrene-poly (ethylene / propylene) -polystyrene (TPS-SEPS), polystyrene- TSP-SEEPS), and polystyrene-poly (ethylene / propylene) -polystyrene (TPS-SEP).

The TPS contained in the film of the present embodiment may be a mixture of two or more different types of TPS. At this time, all or a part of TPS may be composed of a soft segment of a poly (ethylene / propylene) block or a poly (ethylene-ethylene / propylene) random copolymer block. When it is desired to increase the roughening effect of the film, TPS-SEEPS composed of a random copolymer of poly (ethylene-ethylene / propylene) soft segment may be used for all or a part of TPS.

The blending amount of TPS is preferably such that the weight ratio of the SPS resin (a) and the TPS (b) is (a) / (b) = 100/0 to 60/40, more preferably 100/0 to 80/20 Is more preferable. The more the blending amount of TPS is, the more effect of roughening and improvement of flexibility is obtained. On the other hand, if the blending amount of TPS is too large, properties such as heat resistance, chemical resistance and low surface tension characteristic of the SPS resin are lowered.

The filler compounded in the film of the present embodiment is a spherical filler. Since the filler is spherical, the fluidity is good and the resin tends to be highly charged. In addition, since the filler is spherical, the strength of the film is stable even if a force is applied from any direction, so that the mechanical properties of the film are not lowered, and the filler is broken and the film is hardly separated from the film. The sphericity of the spherical filler is preferably 0.80 or more, more preferably 0.90 or more, particularly preferably 0.95 or more.

The spherical filler is preferably amorphous silica. Since amorphous silica is not too hard, the screw or mold of the extruder is hardly worn away during the production of the film. The amorphous silica used as the spherical filler is preferably nonporous amorphous silica. For example, when the amorphous silica is derived from a silica gel, it is preferable to use one which is nonporous by firing.

Another example of non-porous amorphous silica is fused silica. Since fused silica is spheroidized by surface tension by melting the raw material in a flame, there is no sharp point, fluidity in the resin is higher, it is harder to break, and the degree of damage to the mechanical properties of the film is smaller . In addition, when the film of the present embodiment is used as a release film of a semiconductor package, molten silica is contained also in the epoxy resin as a molding material, and even if the molding material is transferred to the molding material, there is no problem.

The particle diameter of the spherical filler is preferably not more than the thickness of the film, more preferably not more than 95% of the film thickness, and more preferably not more than 65% of the film thickness. If a spherical filler having a diameter close to or larger than the film thickness is included, the film tends to be broken at that portion, and the mechanical properties of the film deteriorate. It is preferable that the maximum diameter of the spherical filler is 40% or more of the film thickness as long as it imparts a more textured surface unevenness.

The median diameter d50 of the spherical filler is preferably at least 6% of the film thickness, more preferably at least 10% of the film thickness, particularly preferably at least 20% of the film thickness. If the particle diameter of the filler is too small, surface irregularities of sufficient size can not be obtained. On the other hand, the median diameter (d50) of the spherical filler is preferably 60% or less of the film thickness, more preferably 40% or less of the film thickness. If the median diameter of the filler is too large, the mechanical properties of the film deteriorate. It is preferable that the median diameter (d50) of the spherical filler is in the range of 15 to 35% of the film thickness. In the present specification, the median diameter d50 is a value on a volume basis. This value is consistent with the value on a mass basis or on a weight basis if the filler is made of a single material and the density is constant.

The blending amount of the spherical filler is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, relative to 100 parts by weight of the resin component of the film. So as to obtain surface irregularities of sufficient size. On the other hand, the blending amount of the spherical filler is preferably 20 parts by weight or less based on 100 parts by weight of the resin component of the film. If the amount is too large, the mechanical properties of the film deteriorate.

The film of the present embodiment may contain additives such as an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, a colorant, a nucleating agent and a flame retardant in addition to the above- Particularly, it is preferable that an antioxidant and a lubricant are added to the film used as the release film. The film used as the release film preferably contains an antistatic agent or an antistatic agent such as a surfactant coated on one surface.

Next, characteristics of the film of this embodiment will be described.

It is desirable that the thickness of the film is 10 to 100 占 퐉 in view of ease of manufacture and handling since it can cope with many applications. The thickness of the biaxially stretched film used as the release film is typically 40 to 100 占 퐉, and most typically about 50 占 퐉.

The gloss of the film is represented by a 60-degree specular gloss specified by JISZ8741: 1997, Gs (60 deg.). The degree of gloss required for the film is determined according to the application, and is 30% or less, preferably 20% or less, in order to give a matte tone appearance without feeling "shine" on the surface of the molded article. The lower limit value is not particularly meaningful, but is usually 1% or more.

The surface roughness (Ra) of the film is represented by the arithmetic mean roughness (Ra) specified in JIS B0601: 1994. In order to impart a texture similar to the roll transfer method to the appearance of the matte tone of the film, the surface roughness Ra is 0.8 탆 or more, preferably 1.0 탆 or more. On the other hand, Ra is preferably 3.5 m or less, and more preferably 3.0 m or less. If the Ra is too large, the molding resin can not follow the deep unevenness and a stable molded product surface can not be obtained. Also, if Ra is too large, the deviation from the texture of the surface due to the roll transfer method becomes large.

The tensile elongation of the film refers to a tensile fracture strain or a tensile fracture nominal strain by a tensile test specified in JIS K7127: 1999 (specimen type 2, test speed 200 mm / min). When the film is made of SPS, the tensile elongation refers to the tensile fracture nominal strain since it involves yielding in the tensile test. The tensile elongation of the film is 15% or more, preferably 20% or more, in both the longitudinal direction (MD) and the transverse direction (TD) at room temperature (23 ± 2 ° C., relative humidity 50 ± 10%). On the other hand, although there is no particular problem even if the tensile elongation of the film is excessively large, since SPS is the main component in the present embodiment, it generally does not exceed 200%.

Next, a method of manufacturing the film of this embodiment will be described.

The film of the present embodiment is produced by mixing, melting and kneading an SPS resin, a spherical filler, and other materials, extruding the precursor film (stretched raw film), biaxially stretching the obtained precursor film Can be manufactured.

The precursor film can be produced by a known method. For example, a mixture of desired components may be melted and kneaded by an extruder, and the kneaded product may be extruded from a T-die and then cooled.

The biaxial stretching process is a process of stretching the film in two axial directions, followed by optional thermal fixation. This biaxial stretching process crystallizes the SPS-based resin and increases the glass transition temperature of the film, thereby improving the heat resistance and improving the mechanical strength. In the film of the present embodiment, the surface irregularities are increased by the biaxial stretching process.

The biaxial stretching is performed in the MD and TD directions of the film. The stretching method includes a sequential biaxial stretching method and a simultaneous biaxial stretching method, but it is preferable to use a simultaneous biaxial stretching method because heat stability and tensile elongation can be further improved. For example, according to the simultaneous biaxial stretching method, the difference between the MD direction and the TD direction of the absolute value of the heat shrinkage ratio can be easily reduced. When the biaxial stretching is carried out, the stretching magnification, the stretching temperature and the stretching speed can be appropriately selected in order to obtain the desired thermal stability and mechanical properties.

The heat setting is a treatment for fixing the orientation of the polymer molecules by keeping the stretched film at a temperature not lower than the drawing temperature. The heat treatment temperature, time, and relaxation magnification can be selected as appropriate for obtaining desired heat shrinkage and the like.

Next, the multilayer film of the second embodiment of the present invention will be described.

In the first embodiment, a biaxially oriented film containing a syndiotactic polystyrene (SPS) based resin and a spherical filler has a gloss of 30% or less and a surface roughness (Ra) of 0.8 m or more. , And the characteristic that the tensile elongation is 15% or more is a property of the film itself, that is, a release film. The multilayered film has an SPS-based resin having a gloss of 30% or less, a surface roughness (Ra) of 0.8 탆 or more, and a biaxially oriented film layer containing a spherical filler on at least one surface. If the biaxial oriented film layer has a tensile elongation of 15% or more, it can be used as the biaxially oriented film monolayer, and other layers can be added as a multilayer film. If the biaxially oriented film layer has a tensile elongation of less than 15%, it is sufficient that another layer is added to exhibit a tensile elongation of 15% or more as a multilayer film. Alternatively, another layer having a function such as antistatic property may be added to form a multilayer film.

1, the multilayer film 10 is composed of two layers and includes a first layer 11 constituting a first surface 15 and a second layer 16 adjoining the first layer 16, And a second layer (12) constituting the second layer (12).

The composition and properties of the first layer 11 are the same as those of the polystyrene-based film of the first embodiment. That is, the first layer contains a syndiotactic polystyrene (SPS) based resin and a spherical filler and is biaxially oriented. The first surface 15 has a glossiness of 30% or less and a surface roughness Ra of 0.8 m or more. Further, it is preferable that the first layer should not be broken when the tensile strain of the multilayer film 10 is less than 15%, and not be broken when less than 20%. The preferable composition of the SPS-based resin contained in the first layer, the preferable material of the spherical filler, the particle diameter, the blending amount and the like are also the same as those in the first embodiment. Here, the preferable particle diameter of the spherical filler is relatively determined with respect to the thickness of the first layer, similarly to that in the first embodiment, relative to the thickness of the single-layer film.

The resin for forming the second layer 12 is not particularly limited and may be selected from SPS resins, polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, Can be selected and used. When the mechanical properties of the multilayer film 10 are improved by the second layer, the second layer is preferably made of an SPS-based resin, and more preferably made of the same SPS-based resin as the first layer. This is because the production by co-extrusion is easy as described later. When the second layer is made of SPS resin, the content of the spherical filler of the second layer is preferably less than that of the first layer, and it is more preferable that the second layer does not contain the spherical filler. As a result, the second layer can be made to be a layer superior in mechanical properties to the first layer.

Alternatively, the second layer 12 may be an antistatic layer. The antistatic layer may be a mixture of an antistatic agent with a resin to be a matrix or a layer made of a conductive resin. When the multilayer film 10 is used as a release film for resin molding, the second surface 16 is constituted by the antistatic layer. By using the first surface 15 toward the molding resin side, And at this time, since the second surface 16 is in contact with the metal mold, charging of the multilayer film 10 can be prevented.

In the example illustrated in Fig. 2, the multilayer film 20 is composed of three layers and includes a first layer 11 constituting the first surface 15, a second layer 22 adjacent to the first layer 15, , And a third layer (23) constituting a second surface (26). The first layer of FIG. 2 is the same as the first layer of FIG.

The resin for forming the second layer 22 and the third layer 23 is not particularly limited, and a resin having desired properties can be selected and used. As an example, the second layer may be formed of the same SPS resin as the first layer but may not be a spherical filler, and the third layer may be an antistatic layer. As another example, if the second layer is formed of the same SPS-based resin as the first layer but is formed of a layer not containing a spherical filler and the third layer is formed of the same layer as the first layer, , A multilayered film in which the first surface and the second surface are roughly roughened is obtained.

The layer structure of the multilayer film is not limited to the above. The number of layers can be any number of layers of 2 or more. Since the glossiness and the surface roughness Ra of the first surface are realized by the first layer, the composition and function of each layer other than the first layer can be arbitrarily determined.

Next, a method of manufacturing the multilayer film of the present embodiment will be described.

The multilayer film of the present embodiment may be formed by forming each layer as an independent film and then joining the film through an adhesive layer. For example, the first layer 11 of the polystyrene-based film of the first embodiment can be bonded to another film.

Or when the softening temperature or the viscosity curve of a plurality of resins is close to each other, these resins may be co-extruded to form several layers at the same time. For example, when the first layer 11 and the second layer adjacent thereto are made of the same SPS-based resin, each raw material is melted and kneaded, and a precursor film of a two-layer structure is formed by co- By performing biaxial stretching, the first layer and the second layer can be formed at the same time.

Alternatively, a new layer may be formed by applying a resin material to the surface of another film. For example, the thickness of the antistatic layer is generally 0.1 占 퐉 or less, and it is difficult to form such a thin layer as a single film. In this case, the antistatic layer can be formed by applying a conductive resin to the second surface of the other single layer or multilayer film and drying or crosslinking.

As in the present embodiment, the effect of increasing the degree of freedom of film design can be obtained by multilayering the film. In a single-layer SPS-based film, when the surface roughness is increased, the tensile elongation tends to decrease. On the other hand, in the multilayer film, the composition of the first layer and the like can be adjusted so as to optimize the surface irregularities and texture by realizing the required mechanical properties and the like in the layers other than the first layer.

[Example]

An example of the polystyrene-based film of the first embodiment will be described.

The films of the examples were prepared as follows. (Zareck 142ZE (glass transition temperature: 95 deg. C, melting point: 247 deg. C) manufactured by Idemitsu Kosan Co., Ltd.) was used as the SPS resin. SPS was kneaded at a predetermined ratio and kneaded. The resultant mixture was melt-extruded at 290 DEG C using an extruder equipped with a T-die at the tip thereof and then cooled to obtain a precursor film. This precursor film was simultaneously biaxially stretched at a predetermined magnification at a stretching speed of about 500% / min at 110 캜. After stretching, the film was thermally fixed at 210 DEG C with a relaxation magnification of 0.95 times in the machine direction (MD) and 0.95 times in the transverse direction (TD) to obtain a simultaneous biaxially oriented SPS film having a thickness of about 50 mu m.

An SPS film was produced in the same manner as in Example 1, except that a spherical filler was not added to the film of Comparative Example 1. In the film of Comparative Example 2, a spherical filler was blended with SPS, and an SPS-based film having a thickness of 50 탆 was produced by melt-extrusion without stretching treatment. In the film of Comparative Example 3, an SPS film was produced in the same manner as in Example.

Table 1 shows the kind of spherical filler, particle diameter and blending amount, stretching magnification, thickness, glossiness, surface roughness (Ra) and tensile elongation of the obtained film.

The type, part number and manufacturer of the spherical filler indicated by the symbols in Table 1 are as follows.

F5: silica, FB-5SDC, Denka Co., Ltd.

F7: silica, FB-7SDC, Denka Co., Ltd.

H: Silica, HS-207, Shinnitetsu Sumikin Materielose Co., Ltd.

FE: silica, FEB25A-SQ manufactured by Adomex Co., Ltd.

K: silica, KSE-2045, manufactured by KINSEI TECH CORPORATION

N: Silica, NP-100, AGC manufactured by Sanyo Chemical Industries, Ltd.

S: Aluminosilicate, Siruton JC-50, Mizusawa Kagaku Kogyo Co., Ltd.

Any enamel filler is amorphous. The spherical fillers "F5", "F7", "H", "FE" and "K" are fused silica, and "N" is a spherical silica gel which is fired and fired.

The gloss in Table 1 was measured using a gloss meter (Unigros 60, Konica Minolta K.K.) having a 60-degree specular gloss and Gs (60 deg.) Stipulated in JIS Z8741: 1997. The surface roughness (Ra) was the arithmetic mean roughness (Ra) specified in JIS B0601: 1994, and the surface roughness was measured using a surface roughness meter (Handysurf, Tokyo Seimitsu Co., Ltd.). The tensile elongation was determined from the stress / strain curve measured at a test speed of 200 mm / min using a test piece Type 2 by the method specified in JIS K7127: 1999.

Comparing Comparative Example 1 with Examples 1 to 10, it can be seen that the films of Examples have low gloss, high surface roughness (Ra), and roughened film surface. It was also confirmed that a matte tone was imparted to the film of the examples by visual observation. On the other hand, in the films of Examples 1 to 10, the tensile elongation of the film was lower than that of Comparative Example 1. However, in any of Examples, the film retained 15% or more, and the decrease in mechanical properties due to the mixing of the spherical filler was practically sufficient . ≪ / RTI >

Comparative Example 2 and Example 6 were compared. In Comparative Example 2, which was not drawn, the gloss was low and the surface roughness (Ra) was large, but the tensile elongation was small. In Example 6 in which biaxial stretching was carried out, the gloss was lower, the surface roughness (Ra) was larger, and the tensile elongation sufficient for practical use was obtained.

Comparing Comparative Example 3 and Examples 1 to 10, in Comparative Example 3 using fused silica having a large particle diameter, surface roughness (Ra) was larger than in Examples, but tensile elongation was small. This is presumably because the fused silica of Comparative Example 3 contained particles having a maximum particle size of 67 mu m with respect to the film thickness of 50 mu m, and thus the film was broken by smaller elongation.

Next, an embodiment of the multilayer film of the second embodiment will be described.

The composition of the first layer was the same as that of Example 8. In the second layer, a spherical filler was not added to the same SPS as the first layer. The raw materials of the first layer and the second layer were kneaded, melt-co-extruded at 290 캜 using a two-layer molding extruder, and cooled to obtain a precursor two-layer film. This precursor two-layer film was subjected to simultaneous biaxial stretching and heat setting under the same conditions as in Examples 1 to 10 to obtain a simultaneous biaxially stretched SPS type two-layer film of Example 11 and Example 12. [

Table 2 shows the production conditions, thickness, gloss and surface roughness (Ra) and tensile elongation of the two-layer film of Example 11 and Example 12, respectively.

In Table 2, it can be seen that Examples 11 and 12 have a first surface with a gloss and surface roughness (Ra) equal to those of Example 8, and have a tensile elongation greater than that of Example 8. [ Further, in the measurements of tensile elongation in Examples 11 and 12, the first layer was not broken until the two-layer film reached the fracture.

The present invention is not limited to the above-described embodiments and examples, and various modifications are possible within the scope of the technical idea.

The roughened polystyrene type film and multilayer film of the present invention are particularly useful as a release film during molding such as an epoxy resin printed substrate, particularly a release film (transfer film) having a transfer function, but its application is not limited thereto. In addition to its use as release films, it is useful in a variety of applications where roughening is required. In addition, even when used as a release film, the type of plastic constituting the molding material is not particularly limited, and examples thereof include epoxy resin, phenol resin, melamine resin, urea resin, alkyd resin, polyimide resin, An ester resin, a polyurethane resin, an acrylic resin and the like.

10, 20: multilayer film 11: first layer
12, 22: second layer 23: third layer
15: first surface 16, 26: second surface

Claims (9)

A syndiotactic polystyrene type resin and a spherical filler,
Biaxially oriented,
A polystyrene film having a gloss of 30% or less, a surface roughness (Ra) of 0.8 m or more, and a tensile elongation of 15% or more. The method according to claim 1,
Wherein the spherical filler is amorphous silica. 3. The method of claim 2,
Wherein the spherical filler is fused silica. 4. The method according to any one of claims 1 to 3,
Wherein the spherical filler has a maximum diameter of less than the thickness of the polystyrene-based film and a median diameter (d50) of 6% or more of the thickness of the polystyrene-based film. 4. The method according to any one of claims 1 to 3,
Wherein the amount of the spherical filler to be blended is 5 parts by weight or more and 20 parts by weight or less based on 100 parts by weight of the resin component. 5. The method of claim 4,
Wherein the amount of the spherical filler to be blended is 5 parts by weight or more and 20 parts by weight or less based on 100 parts by weight of the resin component. A biaxially oriented first layer containing a syndiotactic polystyrene type resin and a spherical filler and constituting a first surface having a gloss of 30% or less and a surface roughness (Ra) of 0.8 탆 or more,
And at least one resin layer provided on the opposite side of the first surface of the first layer,
Wherein the first layer is not broken when the tensile elongation is 15% or more and the tensile strain is less than 15%. 8. The method of claim 7,
Wherein the resin layer adjacent to the first layer is made of the same syndiotactic polystyrene resin as the first layer and the content of the spherical filler is smaller than that of the first layer or does not include a spherical filler, . 9. The method according to any one of claims 7 to 8,
And a second surface opposite to the first surface is constituted by an antistatic layer.

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