KR20110000589A - Release film comprising polyphenylene sulfide resin and laminate - Google Patents

Abstract

This invention provides the polyphenylene sulfide resin film and laminated body which are excellent also in heat resistance, chemical-resistance, and adhesiveness to a board | substrate material, as well as peelability from the board | substrate material after a process.
In the present invention, a polyphenylene sulfide resin composition containing 0.1 to 30% by volume of syndiotactic polystyrene is biaxially stretched to have a thickness of 20 to 100 µm, and is used as a release film in a manufacturing process of a rigid substrate. It is set as the release film made of feed resin.

Description

Release film and laminated body made of polyphenylene sulfide resin {RELEASE FILM COMPRISING POLYPHENYLENE SULFIDE RESIN AND LAMINATE}

This invention relates to the laminated body using the polyphenylene sulfide resin release film and this polyphenylene sulfide resin film. More specifically, it is related with the technique of improving the peelability of the film made from polyphenylene sulfide resin.

Circuit boards are one of the main components of electrical products for fixing and wiring electronic components, and are largely divided into rigid substrates using an inflexible insulating substrate and flexible substrates using a thin and flexible insulator substrate. On the other hand, in the manufacturing process of a circuit board and the process of mounting and sealing a semiconductor device on a circuit board, in order to fix and protect a board | substrate material, such as a prepreg, and to prevent leakage of a sealing agent, it is possible to peel after completion of a predetermined process. Release films are used.

Such a release film for circuit boards is subjected to treatments such as heat pressurization and chemical liquid infiltration in a state affixed to a substrate material such as prepreg, and then peeled off, so that not only the adhesion to the substrate material but also heat resistance, chemical resistance and peelability And various properties are required. Therefore, recently, as a release film for circuit boards, polyphenylene sulfide (PPS) films having excellent heat resistance and chemical resistance have begun to be used.

The PPS film is excellent in not only heat resistance and chemical resistance but also moisture resistance and various electrical properties, but various studies have been made to further improve other properties (see Patent Documents 1 to 4). For example, Patent Documents 1 and 2 disclose polyarylene sulfide resin compositions in which a styrene polymer having a syndiotactic structure is mixed in order to improve moldability.

On the other hand, as a manufacturing use of a circuit board, biaxially stretched film (A layer) which consists of a resin composition which has polyphenylene sulfide as a main component in both sides of the resin composition layer (B layer) whose heat distortion temperature is 70-150 degreeC in patent document 3 As a laminated | multilayer film which laminated | stacked), the laminated | multilayer film for mold release which made the thickness ratio of A-layer with respect to whole thickness into the range of 0.05-0.5 is proposed.

In addition, in patent document 4, the average surface roughness of the polyphenylene sulfide layer which forms a mold release surface is 5 nm or more, thickness is 0.1-200 micrometers, and a polyphenylene sulfide layer and another resin layer are laminated | stacked by coextrusion. One substantially unstretched composite sheet is also proposed.

Japanese Patent Laid-Open No. 2-70754 Japanese Patent Laid-Open No. 2-175228 Japanese Patent Laid-Open No. 2006-21372 Japanese Patent Publication No. 2007-216627

However, although the conventional PPS film is excellent in heat resistance and chemical resistance, there exists a problem that adhesiveness with respect to a board | substrate material is high, and it is hard to peel off. On the other hand, although the biaxially stretched film which consists of polyarylene sulfide resin composition described in patent document 2 is excellent in moldability, the peelability with a board | substrate material is not examined.

Moreover, since the film of patent document 3 is a laminated structure, curling tends to occur by the difference of the thermal expansion coefficient of resin which comprises A layer and resin which comprises B layer, and since a PPS film is arrange | positioned at outermost layer, There is a problem that the adhesion strength with the substrate material is large and difficult to peel off. Moreover, since the film of patent document 4 is an unstretched PPS film, when it heats, it weakens and there exists a problem of being unable to bear the stress at the time of peeling, and to be broken.

As such, the conventional PPS film has various problems to be used as a release film for a circuit board. Therefore, a PPS film having a good balance of adhesion and peelability to the substrate material, specifically, during the treatment of chemical infiltration or the like, is in close contact with the substrate material to reliably protect the substrate, and thereafter, when the substrate material becomes unnecessary, There is a demand for a PPS film that can be easily peeled off.

Therefore, a main object of the present invention is to provide a release film and a laminate made of polyphenylene sulfide resin excellent not only in heat resistance, chemical resistance and adhesion to the substrate material, but also in peelability from the substrate material after treatment.

The release film made of polyphenylene sulfide resin according to the present invention is a release film formed by stretching a polyphenylene sulfide resin composition, and the polyphenylene sulfide resin composition contains 0.1 to 30% by volume of syndiotactic polystyrene. The thickness is in the range of 20 to 100 µm.

In addition, content (vol%) of the syndiotactic polystyrene prescribed | regulated here is a conversion value calculated | required from the compounding quantity and density of syndiotactic polystyrene.

In this invention, since it contains a specific amount of syndiotactic polystyrene, peelability from a board | substrate material improves, and since a film is made into a specific thickness, workability becomes favorable and strength also increases by extending | stretching. Thereby, peelability improves from the board | substrate material after a process. As a result, not only the heat resistance which a PPS resin has, the chemical-resistance, the suitable adhesiveness with a board | substrate material, but the outstanding release film which has reverse peeling property is obtained.

In this release film, the element ratio (C / S) of carbon (C) and sulfur (S) on the film surface can be made larger than the central portion in the thickness direction, and in particular, syndiotactic polystyrene content in the polyphenylene sulfide resin composition It is preferable to make 1.0 volume% or more and to set the element ratio (C / S) of carbon (C) and sulfur (S) in a film surface to 7.5 or more. In addition, the film surface in this invention means the area | region from the film surface to several nm depth.

Moreover, the said polyphenylene sulfide resin composition may contain 25 mass parts or less of saturated hydrocarbon copolymers with respect to 100 mass parts of syndiotactic polystyrene.

Moreover, the said polyphenylene sulfide resin composition may contain calcium carbonate: 0.3 mass part or less and calcium stearate: 0.2 mass part or less with respect to 100 mass parts of polyphenylene sulfide.

In addition, these release films can be used, for example in the manufacturing process of a rigid substrate.

The laminated body which concerns on this invention adhere | attached the above-mentioned polyphenylene sulfide resin mold release film on at least one surface of a rigid board | substrate, or multiple rigid board | substrates laminated | stacked through these polyphenylene sulfide resin mold release films. will be.

According to the present invention, since the polyphenylene sulfide contains a specific amount of syndiotactic polystyrene and has a film thickness in a specific range and is formed by stretching, it is not only adhered to the substrate material, but also to chemical resistance and heat resistance. In addition, the release film and laminated body excellent also in the peelability from the substrate material after a process can be implement | achieved.

1: (a) and (b) PPS resin release film formed using the PPS resin composition which contains 7.7 volume% of s-PS and saturated hydrocarbon copolymer in total, and whose s-PS content is 6.0 volume%. Is a cross-sectional TEM photograph.
(A) and (b) are cross-sectional TEM photographs of the PPS resin release film formed using the PPS resin composition containing 7.5 volume% of s-PS.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail. MEANS TO SOLVE THE PROBLEM As a result of earnest experiment study in order to solve the above-mentioned subject, (1) a specific amount of syndiotactic polystyrene (henceforth PPS) is added to polyphenylene sulfide (henceforth PPS). It extended | stretched one PPS resin composition and discovered that the release film made of PPS resin excellent in peelability with a board | substrate material was obtained by making the film thickness after extending | stretching (2) into a specific range, and came to this invention.

Moreover, this inventor adjusts the element ratio (C / S) of carbon (C) and sulfur (S) in the film surface in this release film made from PPS resin, or (4) an elastomer component in PPS resin composition It was discovered that the peelability with the substrate material can be controlled by blending the (saturated hydrocarbon copolymer). In addition, the present inventors do not deteriorate the properties such as peelability even when a filler such as calcium carbonate and calcium stearate is blended with the PPS resin composition, and this PPS resin release film is particularly suitable for use in the manufacturing process of a rigid substrate. It was also found to be desirable.

That is, the PPS resin release film of this invention is a film formed by extending | stretching the PPS resin composition containing 0.1-30 volume% of s-PS, The thickness is 20-100 micrometers. Moreover, in the release film made from PPS resin of this invention, it is preferable that the element surface (C / S) of carbon (C) and sulfur (S) is larger in the film surface than the center of thickness direction, and the s-Ps content in a PPS resin composition is It is more preferable that it is 1.0 volume% or more, and the element ratio (C / S) of carbon (C) and sulfur (S) in a film surface becomes 7.5 or more.

Moreover, it is preferable that the saturated hydrocarbon copolymer: 25 mass parts or less per 100 mass parts of s-PS are mix | blended with the PPS resin composition which comprises the release film made from PPS resin of this invention, and calcium carbonate per 100 mass parts of PPS as needed. : 0.3 mass part or less and calcium stearate: 0.2 mass part or less can also be mix | blended. Moreover, according to this structure, the release film excellent in the adhesiveness with respect to a board | substrate material, chemical-resistance, and heat resistance, as well as the peelability from the substrate material after a process is obtained.

In addition, the peelability of the release film for the substrate depends on the chemical and physical properties of the substrate material to be bonded. The prepreg made to adhere | attach in the release film made from PPS resin of this invention is a kind of substrate material, and impregnates resin in the base material. As a base material used at this time, organic fiber base materials, such as inorganic fiber base materials, such as a glass cloth (glass cloth) and a glass nonwoven fabric, an aramid woven fabric, an aramid nonwoven fabric, paper fiber, and carbon fiber, are mentioned, for example. As the matrix resin impregnated with these substrates, for example, epoxy resin, phenol resin, acrylic resin, amino resin, olefin resin, vinyl resin, imide resin, amide resin, ester resin, ether Various thermosetting resins or thermoplastic resins, such as resin, fluorine resin, cyanate resin, and isocyanate resin, are used. Moreover, such a prepreg is bonded by copper foil etc. and processed into a base copper clad laminated board, and is used as a circuit board.

<About PPS>

First, PPS which is a main component of the release film made from PPS resin of this invention is demonstrated. PPS is a polymer having p-phenylene sulfide represented by the following formula (1) as a repeating unit, and in the PPS resin release film of the present invention, it is an important component in order to secure adhesion, heat resistance and chemical resistance with a substrate material.

Moreover, it is preferable that PPS used by this invention contains 70 mol% or more of p-phenylene sulfide units as a repeating unit in a polymer. When the p-phenylene sulfide unit is less than 70 mol%, the crystallinity and glass transition point of the polymer are lowered, so that the heat resistance and mechanical strength, which are the characteristics of the polymer film containing PPS as a main component, may not be sufficiently exhibited. Moreover, it is more preferable to contain 90 mol% or more of p-phenylene sulfide units.

Moreover, PPS may contain the repeating unit which has a sulfide bond which can superpose | polymerize if it is less than 30 mol%, preferably less than 10 mol% in a repeating unit of a polymer other than a p-phenylene sulfide unit. Although the repeating unit which has this polymerizable sulfide bond is not specifically limited, It is preferable that it is especially the aromatic sulfide unit represented by following General formula (2). In addition, Ar in following formula (2) is an aryl group, For example, each functional group represented by following formula (3-10) is mentioned. In particular, when Ar uses PPS which has an aromatic sulfide unit which is a functional group represented by the said Formula (9), and / or an aromatic sulfide unit which is a functional group represented by following formula (10), excellent heat resistance is obtained. In addition, Q in following formula (6) represents a halogen atom or a methyl group, m shows the integer of 1-4. In the PPS of the present invention, one type of these repeating units may be included alone or in combination of two or more types.

On the other hand, when the PPS is a copolymer containing a monomer unit represented by the formula (2), the form of the polymer may be any one of a random polymer and a block polymer. Moreover, the monomer unit other than the said Formula (1) may exist in the terminal or near terminal.

The PPS in the present invention is determined by the method described in the specification of US Pat. No. 4,464,26, i.e., the alkali metal sulfide and dichlorobenzene are identified under the condition that water is present in a polar solvent such as N-methyl2-pyrrolidone. It can obtain by a step temperature rising polymerization method. By applying this polymerization method, PPS which is substantially linear and has a high molecular weight is obtained. In addition, by adding a small amount of an aromatic halogen compound having three or more halogen substituents at the time of polymerization, PPS having a slight branched or crosslinked structure can be obtained. Moreover, as a manufacturing method of a block copolymer, the method of Unexamined-Japanese-Patent No. 2-225535, the method of Unexamined-Japanese-Patent No. 4-213328, etc. are applicable, for example.

In addition, it is preferable that melt viscosity of PPS is 20-2000 Pa.s when it measures with shear rate 1200 / sec at 310 degreeC. When melt viscosity is less than 20 Pa.s, the mechanical property and heat resistance of a film may fall, and the characteristic as a PPS film may not be acquired, and when melt viscosity exceeds 2000 Pa.s, manufacturing apparatuses, such as an extruder and a filtration apparatus, may be used. This is because a problem may occur due to an increase in the number of. As for the melt viscosity of this PPS, it is more preferable that it is 30-1800 Pa.s. In addition, the shear rate here is a value defined as the inclination speed | rate when a viscous fluid passes between parallel plates.

<about s-PS>

Next, s-PS added to the PPS resin composition which forms the release film made from PPS resin of this invention is demonstrated. s-PS is a styrene polymer which has a syndiotactic structure represented mainly by following formula (11) in a repeating unit. The syndiotactic structure refers to a three-dimensional structure in which a phenyl group or a substituted phenyl group which is a side chain is alternately positioned in the opposite direction with respect to a main chain formed from a carbon-carbon bond.

In addition, s-PS is a catalyst described in, for example, Japanese Patent Laid-Open No. 62-187708, that is, a catalyst of a titanium compound and a condensation product of water and trialkylaluminum in an inert hydrocarbon solvent or in the absence of a solvent as a catalyst. It is obtained by superposing | polymerizing a styrene-type monomer.

Moreover, when this s-PS is mix | blended with a PPS resin composition, there exists an effect which improves peelability with a board | substrate material. However, when the s-PS content in the PPS resin composition is less than 0.1 volume, the effect of addition is not obtained, and since adhesiveness due to PPS is dominant, it is difficult to peel off from the substrate material. Moreover, when s-PS content exceeds 30 volume%, since the amount of PPS in a composition becomes small, adhesiveness, heat resistance, and chemical-resistance with a board | substrate material fall, and the utility as a mold release film falls. Moreover, since moldability falls when s-PS content exceeds 30 volume%, a break may generate | occur | produce at the time of lateral stretch. Therefore, s-PS content in a PPS resin composition shall be 0.1-30 volume%.

On the other hand, it is preferable that s-PS content in a PPS resin composition is 0.3-25 volume%, More preferably, it is 0.5-20 volume%. Thereby, peelability with respect to a board | substrate material can be improved further. In addition, the volume% here is a conversion value and is a value calculated | required from the compounding quantity (mass) and density of s-PS. In addition, the density of PPS was 1.35 g / cm <^3> and the density of s-PS was 1.04 g / cm <^3> at this time.

<About film thickness>

The thickness of the film after extending | stretching affects workability at the time of using as a release film. Specifically, when peeling from a substrate material, since a strong force is applied also to a film, when the thickness is less than 20 micrometers, a film will be easy to tear and workability will fall. On the other hand, when thickness exceeds 100 micrometers, heat will not be uniformly transmitted to the whole film at the time of extending | stretching, and film forming itself becomes difficult. Therefore, the film thickness is 20 to 100 mu m. Moreover, it is preferable to set film thickness to 22.5-80 micrometers, More preferably, it is 25-70 micrometers. Thereby, workability can be improved.

<Element ratio of carbon and sulfur>

In the release film made of PPS resin of the present invention, each of the above-described structural requirements is satisfied, and the element ratio of carbon (C) and sulfur (S) on the film surface (hereinafter referred to as C / S ratio) It is preferable that it is larger than C / S ratio. Thus, favorable release property from a board | substrate material can be obtained stably by making carbon localize on a film surface. Here, a film surface means the area | region to the depth of several nm from a film surface.

It is preferable to make s-PS content in a PPS resin composition 1.0 volume% or more especially, and to make C / S ratio 7.5 or more on a film surface, and can improve peelability on a film surface by this. Specifically, peeling strength with respect to general-purpose multilayer printed wiring board material (FR-4) can be 200 N / m or less. Here, the s-PS content in the PPS resin composition is 1.0 vol% or more because the C / S ratio of the film surface may be less than 7.5 when the s-PS content is less than 1.0 vol%.

In addition, C / S ratio in a film surface and a thickness direction center part can be measured by XPS (X-ray photoelectron spectroscopy), for example. In addition, C / S ratio in a film surface can be adjusted with the compounding quantity of s-PS in a PPS resin composition, the manufacturing conditions mentioned later, etc.

1 and 2 are cross-sectional TEM (Transmission Electron Microscope) photographs of a release film made of PPS resin. 1 is a film formed by using a PPS resin composition containing 7.7 vol% of s-PS and a saturated hydrocarbon copolymer in total and having a s-PS content of 6.0 vol%, and FIG. 2 is 7.5 vol of s-PS. It is a photograph of the film formed using the PPS resin composition containing%. 1 and 2, in the PPS resin release film of the present invention, the bulk s-PS phase is dispersed throughout the film, and its C / S ratio (theoretical value) is about 6.6, but the surface C / S ratio is about 10-13. From this, it is thought that the low molecular weight s-PS and the elastomer component (saturated hydrocarbon copolymer) are localized on the surface.

<About saturated hydrocarbon polymer>

Moreover, a saturated hydrocarbon copolymer may be mix | blended with the PPS resin composition which comprises the release film made from PPS resin of this invention as an elastomer component. In general, PPS and s-PS have low compatibility, but by blending an elastomer component (saturated hydrocarbon copolymer) in the PPS resin composition, the saturated hydrocarbon copolymer acts as a compatibilizer, thereby improving their compatibility. Thereby, the fluctuation | variation of the peeling strength in a film surface and between lots can be suppressed.

Moreover, since the structure of the substance which exists in the film surface changes by mix | blending a saturated hydrocarbon copolymer, the peelability of the release film made of PPS resin and a board | substrate material also changes. That is, in the release film made from PPS resin of this invention, peelability with respect to a board | substrate material can be controlled by adjusting the compounding quantity of the saturated hydrocarbon copolymer to a PPS resin composition.

However, when the compounding quantity of a saturated hydrocarbon copolymer exceeds 25 mass parts with respect to 100 mass parts of s-PS: thermal stability will fall and may decompose when forming a sheet (unstretched film) by extrusion molding. Therefore, when adding a saturated hydrocarbon copolymer to a PPS resin composition, it is preferable to set it as 25 mass parts or less of saturated hydrocarbon copolymers with respect to 100 mass parts of s-PS.

<About calcium carbonate and calcium stearate>

Moreover, calcium carbonate and calcium stearate may be contained in the PPS resin release film of this invention. Calcium carbonate and calcium stearate act as lubricants. However, when the compounding quantity of calcium carbonate exceeds 0.3 mass parts with respect to 100 mass parts of PPS, it may aggregate or break elongation will become difficult, and extending | stretching may become difficult. Moreover, when the compounding quantity of calcium stearate exceeds 0.2 mass part, extrusion failure may arise. Therefore, when mix | blending these with a PPS resin composition, it is preferable to set it as calcium carbonate: 0.3 mass part or less with respect to 100 mass parts of PPS, and to make it calcium calcium stearate: 0.2 mass part or less.

Next, the manufacturing method of the PPS resin release film of this invention is demonstrated. The PPS resin mold release film of this invention is PPS resin which mix | blended predetermined amount with s-PS: 0.1-30 volume% and elastomer components, such as saturated hydrocarbon copolymer, additives, such as calcium carbonate and calcium stearate, as needed in PPS. It can manufacture by extending | stretching the unstretched film formed by melting a composition.

In the present invention, the film is formed by stretching to give strength to the film. The release film requires strength that can withstand the force applied when peeling from the substrate material. However, in the unstretched film, the film is weakened by heating, and thus the film does not withstand the strength when peeled off and the film breaks. Therefore, a film shall be formed into a film by extending | stretching.

When manufacturing the release film made from PPS resin of this invention, PPS pellet and s-PS pellet are weighed first, it mix | blends so that s-PS content may be 0.1-30 volume% (calculated value), and if necessary saturated hydrocarbon copolymer The pellets are blended in a predetermined amount to dry blend and fed to an extruder (hereinafter, this method is referred to as a dry blend system). Or what mix | blended the s-PS pellet so that it might become 0.1-30 volume% (calculated value) to PPS powder, and if necessary, mix | blended a predetermined amount of the pellets of a saturated hydrocarbon copolymer, mixed, remelted, and pelletized It feeds to an extruder (henceforth this method is called a compound system).

At this time, calcium carbonate and calcium stearate may be blended, or pelletized resin compositions containing calcium carbonate and calcium stearate in PPS may be used instead of the PPS pellet. Similarly, what pelletized the resin composition which mix | blended saturated hydrocarbon polymer with s-PS instead of s-PS pellet can also be used. In addition, resin pellets containing a predetermined amount of calcium carbonate and calcium stearate in PPS pellets or PPS, and resin pellets in which a saturated hydrocarbon polymer is blended in s-PS pellets or s-PS include lubricants, plasticizers, antioxidants, and impact-resistant agents. Various additives, such as these, may be mix | blended.

Then, each supplied resin is melted at 280-340 degreeC, it shape | molds in the target film shape with a die, and is discharged. At this time, when the melting temperature is lower than 280 ° C, the PPS is not sufficiently melted. When the melting temperature is higher than 340 ° C, decomposition products of the resin are produced during extrusion. Therefore, melting temperature is set to 280-340 degreeC. Moreover, it is preferable to remove coarse foreign substances, such as a dust | flour or an aggregate of an additive, by filtering a molten resin composition using a filter etc. in this process. Moreover, the unstretched film is obtained by pressing the film discharged | emitted from the die on cooling bodies, such as a metal drum, and cooling and solidifying.

Subsequently, intensity | strength is given to a film by extending | stretching the unstretched film obtained in this way. Although the release film made from PPS resin of this invention may be a stretched film, it is more preferable to set it as a biaxially stretched film. Here, biaxial stretching means stretching in order to provide molecular orientation in a longitudinal direction and a lateral direction. The stretching may be performed in two directions, respectively (hereinafter, referred to as sequential biaxial stretching), or may be simultaneously stretched in two directions. Moreover, re-stretching can also be performed in the vertical and / or horizontal direction.

Hereinafter, the method to manufacture the release film made of PPS resin by sequential biaxial stretching is demonstrated as an example. First, the stretching in the vertical direction will be described. Stretching in the longitudinal direction is usually carried out by the circumferential speed difference of the rolls. This stretching may be performed in one step, or may be performed in multiple steps using a plurality of roll pairs. It is preferable that the surface temperature of the film at the time of longitudinal stretch shall be 80-110 degreeC. When the film surface temperature at the time of extending | stretching becomes less than 80 degreeC, since it becomes below the glass transition temperature of PPS, a film is hard to stretch uniformly. Moreover, when film surface temperature exceeds 110 degreeC, the stick slip which the film adheres intermittently to a extending | stretching roll arises, and uniform extending | stretching becomes difficult. Moreover, as for the film temperature at the time of extending | stretching to a longitudinal direction, it is more preferable to set it as 85-105 degreeC. In addition, the film surface temperature at the time of extending | stretching can be suitably adjusted by changing the temperature of a roll.

In addition, the draw ratio in a vertical direction shall be 2.0-5.0 times. When the draw ratio is less than 2.0 times, it becomes difficult to obtain sufficient strength and heat resistance in the longitudinal direction. On the other hand, when the draw ratio exceeds 5.0 times, the magnification that can be stretched in the transverse direction is lowered, and the balance between physical properties in the longitudinal direction and the transverse direction is broken. In addition, the draw ratio in the longitudinal direction is preferably 2.5 to 4.0 times.

Subsequently, the film stretched in the longitudinal direction by the above-described method and conditions is introduced into a tenter stretching machine, and stretching in the lateral direction is performed by sandwiching both ends of the film with a clip and stretching the film. It is preferable that the film surface temperature at the time of extending | stretching in a horizontal direction shall be 80-110 degreeC. When the temperature at the time of extending | stretching is less than 80 degreeC, it cannot extend | stretch uniformly and it exists in the tendency which becomes difficult to obtain favorable planarity. On the other hand, when film surface temperature exceeds 110 degreeC, orientation crystallization does not fully advance but it exists in the tendency for elasticity modulus and heat resistance to become inadequate. Moreover, as for the film temperature at the time of extending | stretching to a horizontal direction, it is more preferable to set it as 85-105 degreeC.

The draw ratio in the horizontal direction is 2.0 to 5.0 times. When the draw ratio is less than 2.0 times, it cannot be stretched uniformly and may be a cause of poor planarity. On the other hand, when the draw ratio exceeds 5.0 times, the occurrence frequency of breakage increases and the productivity tends to decrease.

By shortening the distance between the clips sandwiching the film immediately after stretching in the transverse direction by 0.1 to 10%, preferably about 0.5 to 7%, the film formed is alleviated, and the film is not less than the melting temperature and less than the melting point in the tenter stretching machine. It is preferable to perform the heat setting treatment at the temperature. Thereby, a heat resistant dimension can be stabilized. It is preferable that the temperature of this heat setting process shall be 240-290 degreeC. When the heat setting temperature is less than 240 ° C., the relaxation efficiency in the transverse direction may decrease, and it may be difficult to obtain a film having excellent dimensional stability under high temperature. When the heat setting temperature exceeds 290 ° C., the melting point of the PPS film may be higher. This is because film forming becomes difficult. In addition, the heat setting treatment temperature is more preferably 250 to 285 ° C.

Moreover, after cooling the film after heat setting treatment to the room temperature in the exit part of a tenter stretching machine, it winds up with a winder and obtains the release film made from PPS resin biaxially stretched.

As mentioned above, since the release film made from PPS resin of this invention is formed from the PPS resin composition containing 0.1-30 volume% of s-PS, it is excellent in peelability from a board | substrate material compared with the conventional PPS film. Moreover, since the thickness of the film obtained by extending | stretching is made into the range of 20-100 micrometers in the release film made from PPS resin of this invention, the outstanding workability and strength as a release film are obtained. As a result, the peelability from the substrate material after the treatment can be improved while maintaining the adhesiveness to the substrate material such as prepreg without reducing the chemical resistance and heat resistance of the PPS.

Moreover, the release film made from PPS resin of this invention can control peeling strength with a board | substrate material by adjusting the C / S ratio in a film surface. The C / S ratio on this film surface can be adjusted by changing the s-PS compounding quantity in a PPS resin composition, and the mixing method and conditions at the time of PPS resin composition manufacture, for example. Moreover, in the PPS resin release film of this invention, peeling strength with respect to general-purpose multilayer printed wiring board material (FR-4) can be made 200 N / m or less by making C / S ratio on the film surface 7.5 or more by such a method. Can be. Thereby, favorable peelability with respect to a board | substrate material can be obtained stably.

Moreover, in the release film made from PPS resin of this invention, since the structure of the substance which exists in the film surface can be changed by mix | blending a saturated hydrocarbon copolymer with a PPS resin composition, a substrate material is adjusted by adjusting the compounding quantity of this saturated hydrocarbon copolymer. It becomes possible to control the peelability with respect to.

The PPS resin release film of this invention mentioned above is suitable for use in the manufacturing process of a rigid board | substrate, For example, the PPS resin release film of this invention adhere | attaches on at least one surface of a rigid board | substrate, or the PPS of this invention A plurality of rigid substrates can be laminated via a resin release film. Moreover, this laminated body can peel a PPS resin release film easily from a board | substrate easily when a PPS resin release film adheres to a board | substrate during processing, and a film becomes unnecessary.

[Example]

Hereinafter, the Example and comparative example of this invention are shown, and the effect of this invention is demonstrated concretely. In addition, this invention is not limited to the Example shown below.

<First Embodiment>

As a first embodiment of the present invention, the films of Examples 1 to 8 and Comparative Examples 1 to 4, which differ in s-PS compounding amount, film thickness, or film forming method, are prepared by the method described below to compare peelability to substrate materials. It was.

(Example 1)

In this embodiment, first, a resin pellet (hereinafter referred to as PPS resin pellet) in which calcium carbonate and calcium stearate was blended with PPS was prepared. Specifically, PPS resin pellets were prepared by pelletizing a mixed powder containing 0.3 parts by mass of calcium carbonate and 0.2 parts by mass of calcium stearate having an average particle diameter of 0.7 µm with respect to 100 parts by mass of PPS powder. Subsequently, the PPS resin pellets and the s-PS pellets were weighed and blended in a volume ratio of 95: 5, and then mixed using a blender to obtain a PPS resin composition. In addition, the volume ratio here is the value converted from the mass and density of PPS and s-PS, making the density of PPS 1.35 g / cm <^3> and the density of s-PS 1.04 g / cm <^3> , and the Example shown below The same applies to the comparative examples.

Subsequently, this PPS resin composition was heated and melted at 310 degreeC using the extruder of diameter 50mm, and it filtered with the disk filter of 10 micrometers of meshes. Subsequently, the molten PPS resin composition is extruded from a die having a linear lip having a length of 560 mm and a gap of 1.1 mm, cast on a metal drum kept at 40 ° C. to cool, and an unstretched film having a thickness of 380 μm. Prepared.

Subsequently, this unstretched film is pre-heated by contacting the metal roll which adjusted the surface temperature to about 85 degreeC, and extending | stretching between rolls is carried out so that the length of a longitudinal direction may become 3.4 times on the metal roll which adjusted the surface temperature to about 90 degreeC. It was. Next, the film stretched in the longitudinal direction was introduced into a tenter stretching machine, and stretched 2.8 times in the transverse direction in an atmosphere at 93 ° C. After extending | stretching, it heat-fixed at 250 degreeC for about 90 second, immediately relaxing about 4% in a horizontal direction, and obtained the biaxially stretched film whose thickness is about 40 micrometers.

(Example 2)

Using the PPS resin composition in which the PPS resin pellets and the s-PS pellets were mixed in a volume ratio of 93: 7 in the same manner as in Example 1 above, they were extruded under the same conditions as in Example 1, and the thickness was 380 µm. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm.

(Example 3)

Unstretched with a thickness of 380 µm by extrusion under the same conditions as in Example 1, using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a ratio of 90:10 by volume in the same manner as in Example 1 above. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm.

(Example 4)

Unstretched with a thickness of 300 μm by extrusion under the same conditions as in Example 1 using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a ratio of 90:10 by volume in the same manner as in Example 1 above. A film was obtained. Subsequently, after extending | stretching this unstretched film in the vertical and horizontal direction on the conditions similar to Example 1, it relaxed and obtained the biaxially stretched film whose thickness is about 32 micrometers.

(Example 5)

Unstretched with a thickness of 500 μm by extrusion under the same conditions as in Example 1, using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a ratio of 90:10 by volume in the same manner as in Example 1 above. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 53 μm.

(Example 6)

In the same manner as in Example 1, using the PPS resin composition in which the PPS resin pellets and the s-PS pellets were mixed at a volume ratio of 80:20, extruded under the same conditions as in Example 1, and the thickness was 380 µm. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm.

(Example 7)

Unstretched with a thickness of 380 µm by extrusion under the same conditions as in Example 1, using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a volume ratio of 99.8: 0.2 in the same manner as in Example 1 above. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm.

(Example 8)

Unstretched with a thickness of 380 µm by extrusion under the same conditions as in Example 1, using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a volume ratio of 75:25 in the same manner as in Example 1 above. A film was obtained. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm.

(Comparative Example 1)

As Comparative Example 1 of the present invention, extrusion was carried out under the same conditions as in Example 1 using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a volume ratio of 50:50 in the same manner as in Example 1 above. To obtain an unstretched film having a thickness of 380 µm. Subsequently, this unstretched film was stretched in the vertical and transverse directions under the same conditions as in Example 1, and then relaxed to obtain a biaxially stretched film having a thickness of about 40 μm. However, in this comparative example, many breaks occurred at the time of lateral stretching, and continuous film forming was difficult.

(Comparative Example 2)

As Comparative Example 2 of the present invention, a release film made of PPS resin without adding s-PS was prepared. Specifically, a resin pellet containing PPS prepared in the same manner as in Example 1 as a main component was melted, filtered and cast in the same manner as in Example 1 to prepare an unstretched film having a thickness of 440 μm.

Subsequently, this unstretched film is pre-heated by contacting the metal roll which adjusted the surface temperature to about 85 degreeC, and extending | stretching between rolls is carried out so that the length of a longitudinal direction may become 3.4 times on the metal roll which adjusted the surface temperature to about 90 degreeC. It was. Subsequently, the film stretched in the longitudinal direction was introduced into a tenter stretching machine, stretched 3.2 times in the transverse direction in an atmosphere at 93 ° C., and immediately relaxed about 3% in the transverse direction. Thereafter, the film was heat set at 260 ° C. for about 50 seconds to obtain a biaxially oriented film having a thickness of about 40 μm.

(Comparative Example 3)

As Comparative Example 3 of the present invention, extrusion was carried out under the same conditions as in Example 1, using a PPS resin composition obtained by mixing PPS resin pellets and s-PS pellets in a ratio of 90:10 by volume in the same manner as in Example 1 described above. To obtain an unstretched film having a thickness of 200 μm. Subsequently, this unoriented film was stretched 3.4 times in the longitudinal direction and 3.6 times in the horizontal direction, and then relaxed to obtain a biaxially stretched film having a thickness of about 16 μm.

(Comparative Example 4)

As Comparative Example 4 of the present invention, in the same manner as in Example 1 described above, the PPS resin pellets and the s-PS pellets were extruded using a PPS resin composition mixed at a volume ratio of 90:10, and wound up in a cooling drum. It carried out at high speed and obtained the unstretched film whose thickness is 40 micrometers.

Next, peelability was evaluated about each film of the Example and comparative example which were manufactured by the said method. Specifically, the both sides of the prepreg (manufactured by Sumitomo Bakelite Co., Ltd., prepreg FR-4 for epoxy multilayer printed wiring boards (model number: EI-6765)) are sandwiched with respective films of Examples or Comparative Examples, and a press machine is used. The mixture was held at 125 ° C. for 30 minutes, semi-cured, and then pressurized for 45 minutes under conditions of 175 ° C. and 2.2 MPa (22.5 kgf / cm ² ) to cure the prepreg.

Then, each film thermocompression-bonded to the prepreg was peeled by hand, and the peelability of the film was evaluated. The evaluation result was that the film could be easily peeled from the prepreg without cracking or tearing, that the film was peeled from the prepreg, but that the peeling strength was high △, the film strength was low and the film was torn during peeling and workability The thing which fell and the thing with which adhesive strength with a prepreg was large and a film was not peeled was made into x. The above result is put together in following Table 1, and is shown.

As shown in Table 1, the films of Examples 1 to 8 in which s-PS was added to the PPS within the scope of the present invention could be easily peeled off, and in particular, the s-PS content was in the range of 0.5 to 20% by volume. The film of Examples 1-6 in inside showed the outstanding peelability which has not existed conventionally.

On the other hand, the film of the comparative example 1 whose s-PS content is 50 volume% generate | occur | produced many breaks at the time of lateral stretch, and film forming was difficult. Moreover, the film of the comparative example 2 which did not add s-PS was high in adhesiveness with a prepreg, and was not peelable. Moreover, since the film of the comparative example 3 whose film thickness is 16 micrometers is thin, it is easy to tear a film at the time of peeling, and it was unsuitable as a release film. Moreover, since the unstretched film of the comparative example 4 was low in strength and weakened by heating, the film broke when it peeled.

The release film made of PPS resin of the present Example which added s-PS to PPS within the range of this invention as mentioned above, and formed into a film by extending | stretching so that the thickness of a film might fall in the range of this invention compares it deviates from the range of this invention. It was confirmed that peelability and heat resistance were excellent compared with the film of an example.

Second Embodiment

As a 2nd Example of this invention, the film of Examples No. 11-19 from which the C / S ratio in a film surface differs was manufactured by the method and conditions shown below, and peeling strength with respect to the board | substrate material was measured. In the present Example, PPS resin composition was manufactured by mix | blending s-PS etc. with PPS by a dry blend system (D) or a compound system (P) first.

Specifically, in the films of Nos. 11 to 16 and 19 produced by the dry blending method, PPS resin pellets (Nos. 12 to 16, which were pelletized by mixing calcium carbonate and calcium stearate with PPS pellets (number 11) or PPS) 19) was blended with s-PS pellets, and for some samples (numbers 15-19), saturated hydrocarbon copolymer pellets were also blended, dry blended and fed to the extruder. On the other hand, in the films 17 and 18 produced by the compound method, s-PS pellets and saturated hydrocarbon copolymer pellets are blended with PPS powder, and the films of number 17 are also mixed with calcium carbonate and calcium stearate, and then mixed. What was remelted and pelletized was fed to the extruder.

At this time, three kinds of pellets (s-PS type: A to C) having different molecular weights are used for s-PS, and blended so that the s-PS content in the PPS resin composition is 0.1 to 30% by volume (converted value). It was. In addition, styrene ethylene butylene styrene block copolymer was used for saturated hydrocarbon copolymer, and the compounding quantity was 25 mass parts with respect to 100 mass parts of s-PS. In addition, the compounding quantity of calcium carbonate was 0.3 mass part per 100 mass parts PPS :, and the compounding quantity of calcium stearate was 0.2 mass part per 100 mass parts PPS :.

Subsequently, this PPS resin composition was heated and melted at 310 degreeC using the extruder of diameter 50mm, and it filtered with the disk filter of 10 micrometers of meshes. Next, the molten PPS resin composition was extruded from a die having a linear lip having a length of 560 mm and a gap of 1.1 mm, cast on a metal drum kept at 40 ° C, and cooled to prepare an unstretched film.

Subsequently, this unstretched film was preheated by contacting the metal roll which adjusted the surface temperature to about 85 degreeC, and was respectively 3.4 times or 3.5 times the length of a longitudinal direction on the metal roll which adjusted the surface temperature to about 90 degreeC, respectively. Stretching between rolls was performed. Subsequently, the film stretched in the longitudinal direction was introduced into a tenter stretching machine and stretched so as to be 2.9 times or 3.0 times in the transverse direction, respectively, in an atmosphere at 93 ° C. Immediately after stretching, heat setting was performed for 40 seconds or 100 seconds under 250 ° C or 260 ° C temperature, while relaxing about 3%, 4% or 4.7% in the transverse direction immediately to obtain a biaxially stretched film having a thickness of about 40 µm.

In addition, as a comparative example of the present invention, the film of No. 20 was prepared without blending s-PS. Specifically, PPS resin pellets which were pelletized by mixing PPS: 100 parts by mass with calcium carbonate: 0.3 parts by mass and calcium stearate: 0.2 parts by mass were melted and filtered in the same manner as in Example 1, and then cast. An unstretched film of 380 μm was prepared.

The unstretched film was subjected to preheating by contacting the metal roll with the surface temperature adjusted to about 85 ° C., and then stretched between rolls so that the length in the longitudinal direction was 3.5 times on the metal roll with the surface temperature adjusted to about 90 ° C. It was. Subsequently, the film stretched in the longitudinal direction was introduced into a tenter stretching machine, stretched 2.9 times in the transverse direction in an atmosphere at 93 ° C., and immediately relaxed about 4% in the transverse direction. Thereafter, heat setting was performed at 250 ° C. for about 100 seconds to obtain a biaxially oriented film having a thickness of about 40 μm.

Next, peeling strength was measured about each film of the Example and comparative example which were manufactured by the said method. Specifically, both sides of the prepreg (manufactured by Sumitomo Bakelite Co., Ltd., prepreg FR-4 for epoxy multilayer printed wiring boards (model number: EI-6765)) are sandwiched with respective films of Examples or Comparative Examples, After holding for 30 minutes at 125 ° C. for semi-curing, the prepreg was cured by pressing for 45 minutes under conditions of 175 ° C. and 2.2 MPa (22.5 kgf / cm ² ).

In addition, a strip-shaped test piece having a width of 15 mm was cut from the laminate of the film and the prepreg. Moreover, in the state which arrange | positioned this test piece so that a prepreg might be horizontal, the film was stretched in the vertical direction, and 90 degree peeling strength was measured. At this time, Tensileon (TENSILON) RTC-1210A manufactured by Endi Corporation was used for the tensile tester, and the test speed was 50 mm / min, and the test environment was 23 ° C. and 50% RH. In addition, the measurement of peeling strength was performed about nine test pieces, and the average was taken.

In addition, for each film of Examples and Comparative Examples, XPS (Albac Pais, Quanterra SX) was used to analyze the types of elements, their abundance ratios and chemical states of about several nm depth from the surface. It carried out and calculated | required the C / S ratio of the surface. At this time, monochrome Al rays (1486.6 eV) were used for the X-ray source. In addition, the detection region was 100 μmφ, and the detection depth was about 4 to 5 nm (extraction angle 45 °). The above result is put together in following Table 2, and is shown. In addition, the following Table 2 also shows the manufacturing conditions of each film, and the measurement (theoretical value) of C / S ratio in a film center part.

As shown in the said Table 2, as a result of the measurement in XPS, it was confirmed that the film produced this time has a C / S ratio of the film surface higher than the center part of thickness direction, and C is unevenly distributed on the surface. In particular, the films of Examples Nos. 11 to 18 having a C / S ratio of 7.5 or more on the surface of the film were superior in peelability compared to films of No. 19 having a C / S ratio of less than 7.5, and both had a peel strength of 200 N from the substrate. could be reduced below / m. Moreover, since the film of the comparative example No. 20 which does not mix | blend s-PS has a C / S ratio of 6 low, peeling strength is high and it breaks when peeling from a board | substrate, and peeling strength was not able to be measured. From the above result, it turned out that peeling characteristic from a board | substrate material improves by making C / S ratio into 7.5 or more on the film surface.

Claims (8)

As a release film formed by extending | stretching a polyphenylene sulfide resin composition,
The polyphenylene sulfide resin composition contains 0.1 to 30% by volume of syndiotactic polystyrene,
Film thickness of 20 to 100 μm
Release film made of polyphenylene sulfide resin. The release film made of polyphenylene sulfide resin according to claim 1, wherein the film surface has a larger element ratio (C / S) of carbon (C) and sulfur (S) than the central portion in the thickness direction. The syndiotactic polystyrene content of the said polyphenylene sulfide resin composition is 1.0 volume% or more,
The element ratio (C / S) of carbon (C) and sulfur (S) on a film surface is 7.5 or more, The release film made from polyphenylene sulfide resin characterized by the above-mentioned. The polyphenylene sulfide according to any one of claims 1 to 3, wherein the polyphenylene sulfide resin composition contains 25 parts by mass or less of a saturated hydrocarbon copolymer with respect to 100 parts by mass of syndiotactic polystyrene. Release film made of feed resin. The polyphenylene sulfide resin composition according to any one of claims 1 to 4, wherein the polyphenylene sulfide resin composition contains calcium carbonate: 0.3 parts by mass or less and calcium stearate: 0.2 parts by mass or less with respect to 100 parts by mass of syndiotactic polystyrene. There is a release film made of polyphenylene sulfide resin. The release film made of polyphenylene sulfide resin according to any one of claims 1 to 5, which is used in a process for producing a rigid substrate. The laminated body which adhere | attached the release film made from the polyphenylene sulfide resin of any one of Claims 1-5 to at least one surface of a rigid substrate. The laminated body by which the several rigid substrate was laminated | stacked through the release film made from the polyphenylene sulfide resin in any one of Claims 1-5.

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