JP4190978B2 - Laminated polyester film for dry film resist - Google Patents

Description

  The present invention relates to a laminated polyester film for dry film resist used for a dry film resist used for manufacturing an electronic circuit board. More specifically, the present invention relates to a laminated polyester film for dry film resist that is excellent in winding property, can more reliably prevent the occurrence of circuit defects, and can further improve the resolution.

  In recent years, the dry film resist method (DFR method) is used for manufacturing electronic circuit boards, and the dry film resist is formed by laminating a support layer, a photoresist layer made of a photosensitive resin material, and a protective layer. . And when manufacturing an electronic circuit board, after peeling a protective layer from dry film resist first, the photoresist layer exposed on the copper layer surface of the epoxy resin board | substrate with which the copper layer is laminated | stacked on the surface is affixed, for example. Next, after the glass plate on which the circuit is printed is adhered to the surface of the support layer, light is irradiated from the glass plate side. This light is irradiated on the photoresist layer after passing through the transparent portion and the support layer in the circuit image printed on the glass plate. For this reason, the portion irradiated with light in the photoresist layer is cured by light. Subsequently, after removing the glass plate and the support layer, the uncured portion of the photoresist layer is removed, and etching is performed using an acid or the like. At this time, the removal of the uncured portion of the photoresist layer exposes the corresponding copper layer, and the copper layer exposed by etching is removed from the epoxy resin substrate to form a circuit on the epoxy resin substrate. Then, the electronic circuit board is manufactured by removing the cured photoresist layer.

  As the support layer, a polyester film is mainly used because it is excellent in mechanical properties, optical properties, chemical resistance, heat resistance, dimensional stability, flatness and the like. Conventionally, this type of polyester film is a biaxially oriented laminated polyester film containing particles having an average particle diameter of 0.01 to 3.0 μm in at least one outermost layer, and the centerline average roughness of the outermost layer. Ra is 0.005 μm or more, the maximum height Rt is less than 1.5 μm, and the haze value is set to 1.5% or less (see, for example, Patent Document 1). And the processus | protrusion is formed in the surface of a polyester film with the particle | grains contained in the outermost layer, the slipperiness of a polyester film is improved, and the handleability is improved. Furthermore, by setting the average particle diameter, the center line average roughness Ra, and the maximum height Rt within the above ranges, the slipperiness of the polyester film is further improved to improve the handleability, and the polyester film and the glass plate To improve the resolution by preventing the formation of bubbles between them. In addition, by setting the haze value in the above range, the transparency of the polyester film is improved and the resolution is further improved.

In addition, the light transmittance at a wavelength of 365 nm is set to 86% or more, and the number of fly specs having a diameter of 20 μm or more is set to 10/10 cm ² or less (see, for example, Patent Document 2). . And, by setting the light transmittance to the above range, the resolution is improved, and by setting the content of the fly spec to the above range, a circuit defect caused by the fly spec occurs in the manufactured electronic circuit board. Suppress.
JP-A-7-333853 (pages 2 to 6) JP 2002-62661 A (pages 2 to 5)

  However, in the production of polyester such as polyethylene terephthalate constituting the film, the metal catalyst and additive particles used may produce aggregates. For this reason, in the former polyester film, the resolution can be improved by having the center line average roughness Ra or the like in the above range, but the light transmitted through the glass plate by the aggregate is blocked. There is a problem that a circuit defect may occur or the resolution may be lowered. On the other hand, in the latter polyester film, the occurrence of circuit defects due to fly specs can be suppressed by making the number of fly specs within the above range, but porous silica used for imparting winding property Agglomerated particles such as, etc., are largely flattened in the in-plane direction of the film in biaxial stretching during film molding, and become fly spec. For this reason, the suppression of fly specs reduces the amount of added particles, and there is a problem that the winding property is deteriorated.

  The present invention has been made paying attention to such problems existing in the prior art. An object of the present invention is to provide a laminated polyester film for dry film resist that is excellent in winding property, can more reliably prevent the occurrence of circuit defects, and can further improve the resolution.

In order to achieve the above object, the laminated polyester film for dry film resist according to claim 1 is a laminated polyester film for dry film resist comprising at least two polyester layers, and is at least one outermost layer. Contains particles having an average particle diameter of 0.01 to 3.0 μm, the center line average roughness Ra of the surface is 0.002 to 0.030 μm, and the maximum height Rt is 0.05 to 1.0 μm. , and the in the whole polyester layer, the major axis is the number of 10μm or more metal-containing aggregates 5/10 cm ² Ri der below contains the metal-containing aggregates antimony content of antimony in entire polyester layer The amount is 30-120 ppm .

The laminated polyester film for dry film resist according to claim 2 has a haze value of 3.0% or less in the invention according to claim 1 .

As described in detail above, the present invention has the following effects.
According to the laminated polyester film for dry film resist of the invention described in claim 1, it is excellent in winding property, can more reliably prevent the occurrence of circuit defects, and can further improve the resolution.

According to the laminated polyester film for dry film resist of the invention described in claim 2 , in addition to the effect of the invention described in claim 1 , the resolution can be further improved.

Hereinafter, embodiments embodying the present invention will be described.
The laminated polyester film for dry film resist of the present embodiment (hereinafter also referred to as a laminated film) is formed by laminating a plurality of polyester layers. This laminated film is overlaid on a photoresist layer to form a dry film resist, which is used for manufacturing an electronic circuit board such as a printed wiring board. In the following, the polyester layer (A) (hereinafter also referred to as A layer) and the polyester layer (B) (hereinafter also referred to as B layer) are laminated in the order of A / B / A. The laminated film formed by will be described.

  The A layer constituting the laminated film is formed of the following polyester. That is, the polyester contains a polyester of an aromatic dicarboxylic acid or its ester and glycol as a main component, that is, 50% by mass or more, and 80% or more of the repeating structural units are ethylene terephthalate units or ethylene-2,6- Those having naphthalate units are preferred. Specific examples of the aromatic dicarboxylic acid include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, phthalic acid, adipic acid, sebacic acid, 4,4′-diphenyldicarboxylic acid, p-oxyethoxybenzoic acid, and the like. Examples include oxycarboxylic acid. On the other hand, specific examples of glycol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol and the like.

  This polyester may be configured as a copolyester containing a third component. Specific examples of the third component at this time include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, phthalic acid, adipic acid, sebacic acid, 4,4 ′ as an aromatic dicarboxylic acid different from the main component. -Oxycarboxylic acids such as diphenyldicarboxylic acid and p-oxyethoxybenzoic acid, diphenylsulfodicarboxylic acid, diphenyletherdicarboxylic acid, diphenoxyethanedicarboxylic acid, cyclohexanedicarboxylic acid, diphenylthioetherdicarboxylic acid, diphenylketonedicarboxylic acid, phenylindanedicarboxylic acid Eicoic acid, dodecanedicarboxylic acid, dimer acid, aromatic dicarboxylic acid having metal sulfonate, polyether dicarboxylic acid and the like. These aromatic dicarboxylic acids may be contained alone or in combination of two or more.

  On the other hand, specific examples of glycols different from the main component include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, tetramethylene glycol, 1,4-cyclohexanedi Examples include methanol, 2,2-bis (4-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, hydroquinone, cyclohexanediol, and polyalkylene glycol. These glycols may be contained alone or in combination of two or more.

  This polyester can be obtained by polycondensing an ester compound of an aromatic dicarboxylic acid and a glycol. It can also be obtained by a method in which an aromatic dicarboxylic acid dialkyl ester and a glycol are subjected to a transesterification reaction and then polycondensed, or a method in which a diglycol ester of an aromatic dicarboxylic acid is polycondensed.

  A catalyst is used in the transesterification reaction or polycondensation reaction. Specific examples of the catalyst used in the transesterification reaction include metal compounds such as alkali metals, alkaline earth metals, zinc, lead, manganese, and aluminum, or reaction products thereof. And the like including On the other hand, specific examples of the catalyst used for the polycondensation reaction include an antimony compound such as antimony oxide, a germanium compound such as germanium oxide, a metal compound such as an organic titanium compound or a reaction product thereof. Specific examples of antimony oxide include antimony trioxide and the like, and specific examples of the reaction product of antimony oxide include antimony metal which is a reduced form thereof. These may constitute a catalyst alone, or a combination of two or more may constitute a catalyst.

  Specific examples of the polyester include polyethylene terephthalate (PET), polyethylene-2,6-naphthalenedicarboxylate (PEN), polycyclohexanedimethylene terephthalate (PCT), and the like. This polyester may contain polyethylene, polystyrene, polycarbonate, polysulfone, polyphenylene sulfide, polyamide or polyimide in an amount of 1% by mass or less based on the total amount, antioxidant, heat stabilizer, antistatic agent, lubrication. Agents, dyes, pigments and the like may be included.

  The intrinsic viscosity of the polyester is preferably 0.45 to 1.0, more preferably 0.50 to 0.80. If the intrinsic viscosity is less than 0.45, film breakage may occur when a laminated film is produced. On the other hand, when the ratio exceeds 1.0, the polyester has a high viscosity, and the production of the polyester and the production of the laminated film become complicated, which may reduce the efficiency.

  Each polyester layer may be formed of polyesters having different melting points, such as those forming the A layer having a lower melting point than those forming the B layer. At this time, the polyester forming the A layer is preferably a copolyester containing 50 mol% or more of the constituent components of the polyester forming the B layer because peeling of the A layer and the B layer can be prevented.

  A layer is comprised as the outermost layer of a laminated | multilayer film, and the processus | protrusion resulting from particle | grains is formed in the surface by containing particle | grains. Specific examples of particles include inorganic particles such as calcium carbonate, calcium phosphate, silica (silicon dioxide), kaolin, talc, titanium dioxide, alumina (aluminum oxide), barium sulfate, calcium fluoride, lithium fluoride, zeolite, and molybdenum sulfide. And organic particles such as crosslinked polymer particles and calcium oxalate. These may be contained alone or in combination of two or more. Furthermore, the same kind of particles having different average particle diameters may be combined and contained. Among these, silica particles such as amorphous silica particles and spherical silica particles or high spherical cross-linking are used because they have high affinity with polyester and low refractive index of light and can suppress a decrease in transparency of the laminated film. Crosslinked polymer particles such as molecular particles are preferred.

  Here, for example, after dissolving a water-soluble polymerization initiator such as potassium persulfate and a dispersion stabilizer such as sodium lauryl in demineralized water, a mixed solution of styrene, methyl methacrylate and divinylbenzene is added to the solution to conduct a polymerization reaction. Do. Then, a partially ammonium neutralized product of sodium polyacrylate-methoxypolyethylene glycol-polypropylene glycol monomethacrylate copolymer and ethylene glycol are added, and water is distilled off under heating and reduced pressure to obtain crosslinked polymer particles.

  The average particle diameter of the particles is 0.01 to 3.0 μm, preferably 0.1 to 3.0 μm, more preferably 0.1 to 2.0 μm. When the average particle diameter is less than 0.01 μm, no protrusions can be formed on the surface of the layer A, the slipperiness of the laminated film is lowered and the winding property is lowered. Further, when the glass plate is brought into close contact with the surface of the A layer, a part of air remains between the A layer and the glass plate to form bubbles, and the light is refracted by the bubbles to reduce the resolution. On the other hand, if the thickness exceeds 3.0 μm, the protrusions formed on the surface of the A layer become large, causing poor adhesion between the surface of the A layer and the glass plate, resulting in a decrease in resolution.

  Here, the ratio (d / t) between the average particle diameter d (μm) of the particles contained in the A layer and the thickness t (μm) of the A layer is preferably 0.5 to 10, and preferably 0.5 to 8 Is more preferable, and 0.8 to 5 is more preferable. If d / t is less than 0.5, the number of protrusions formed on the surface of the A layer is reduced, and the slipperiness of the laminated film is lowered, and the winding property may be lowered. On the other hand, if it exceeds 10, the particles may fall off from the A layer.

  The content of the particles in the A layer is preferably 0.1 to 20.0% by mass, more preferably 0.1 to 5.0% by mass, and still more preferably 0.2% with respect to the polyester forming the A layer. It is -2.0 mass%. When the content of the particles is less than 0.1% by mass, the number of protrusions formed on the surface of the A layer becomes insufficient, and the slipperiness of the laminated film cannot be sufficiently improved, and the glass plate is adhered to the surface of the A layer. There is a possibility that bubbles may be formed between them when they are made. On the other hand, if it exceeds 20.0% by mass, the particles may fall off from the A layer, and the particles may aggregate to form coarse protrusions.

  The particles are blended into the polyester according to conventional methods. For example, particles are added in any process that produces polyester. That is, it is preferable to disperse the particles in ethylene glycol or the like and add them as a slurry in the esterification step or the step after the end of the transesterification reaction and before the start of the polycondensation reaction. Moreover, you may melt-knead the dry particle | grains or its slurry, and polyester. When blending the particles with the polyester, the particles may be subjected to a treatment such as crushing in advance.

  The center line average roughness Ra of the surface of the A layer is 0.002 to 0.030 μm, preferably 0.005 to 0.025 μm, and the maximum height Rt is 0.05 to 1.0 μm, preferably 0.1 to 0.1 μm. 0.8 μm. When the center line average roughness Ra is less than 0.002 μm or the maximum height Rt is less than 0.05 μm, the planarity of the surface of the A layer is too high, so that the slipping property of the laminated film is lowered and the winding property is lowered. On the other hand, when the center line average roughness Ra exceeds 0.030 μm, or when the maximum height Rt exceeds 1.0 μm, a poor adhesion between the surface of the layer A and the glass plate occurs and the resolution decreases.

  Then, the B layer which comprises a laminated | multilayer film is formed with the said polyester like the A layer. The B layer may contain particles in the same manner as the A layer. At this time, the content of the particles in the B layer is preferably equal to or less than the content of the particles in the A layer, and the content of the particles in the entire laminated film is preferably 0.2% by mass or less based on the entire polyester. .1% by mass or less is more preferable. When the content of the particles in the B layer or the content of the particles in the entire laminated film exceeds the above range, the transparency of the laminated film may be lowered.

  The laminated film is produced by a co-extrusion method, a dry lamination method, or the like, but the co-extrusion method is preferred because the production efficiency of the laminated film is high. The thickness of the laminated film is preferably 5 to 30 μm, and the thickness of the A layer is preferably 0.005 to 3 μm. When the thickness of the laminated film is less than 5 μm, the film forming property tends to be lowered. Further, if the thickness of the A layer is less than 0.005 μm, the particles may fall off from the A layer. On the other hand, when the thickness of the laminated film exceeds 30 μm, or when the thickness of the A layer exceeds 3 μm, the manufacturing cost may increase and it is difficult to save resources.

The number of metal-containing aggregates having a major axis of 10 μm or more in the entire polyester layer, that is, in the laminated film is 5/10 cm ² or less, more preferably 3/10 cm ² or less. Here, the metal-containing aggregate is formed by depositing and aggregating the catalyst added when the polyester is produced and remaining in the laminated film, and has a light shielding property. For example, when antimony trioxide is used in the production of polyester, the remaining antimony precipitates and aggregates to form an antimony-containing aggregate, that is, an antimony-containing aggregate. For this reason, the antimony containing aggregate which has light-shielding property exists in the laminated | multilayer film using polyester, and it expands in a film plane by biaxially stretching. Therefore, when the number of metal-containing aggregates having a major axis of 10 μm or more exceeds 5/10 cm ² , the ratio of light transmitted through the laminated film being blocked by the metal-containing aggregates increases, and the resolution of the laminated film decreases. In addition, many circuit defects occur in the manufactured electronic circuit board.

  The major axis of the metal-containing aggregate is determined by measuring the maximum diameter of the metal-containing aggregate using an optical microscope, a scanning electron microscope, or the like. Here, the width of the circuit formed by the dry film resist is, for example, 10 to 50 μm, and light is transmitted through the laminated film with a width of, for example, 10 to 50 μm. For this reason, the metal-containing aggregates having a major axis of less than 10 μm have a low light shielding degree with respect to light transmitted through the laminated film with a width of 10 to 50 μm, and circuit defects due to the metal-containing aggregates do not occur. Therefore, about the metal containing aggregate in a laminated film, it is necessary to set the thing whose major axis is 10 micrometers or more in the said range.

  Specific examples of the metal contained in the metal-containing aggregate include metals used as the catalyst, and among these, antimony has higher light shielding properties than other metals. For this reason, it is preferable to set the content of the antimony-containing aggregate in the above-mentioned range among the metal-containing aggregates, because circuit defects can be reliably prevented. Here, the type of metal contained in the metal-containing aggregate is elemental analysis using an electron beam probe X-ray microanalyzer (EPMA), a scanning electron microscope-energy dispersive X-ray analyzer (SEM-EDX), or the like. It can be specified by law.

  The content of antimony in the laminated film is preferably 150 ppm or less, and more preferably 30 to 120 ppm. When the content of antimony exceeds 150 ppm, the number of antimony-containing aggregates in the laminated film increases, and the rate at which transmitted light is shielded by the antimony-containing aggregates increases, thereby reducing the resolution of the laminated film. A circuit defect occurs in the electronic circuit board manufactured together. The content of antimony in the laminated film is due to the amount of antimony as a polycondensation catalyst when producing polyester. For this reason, when the content of antimony is less than 30 ppm, there is a possibility that the production efficiency of the polyester is lowered because the amount of the catalyst is small. The content of antimony in the laminated film can be quantified by fluorescent X-ray analysis or the like. Here, when the A layer and the B layer are formed of different polyesters, the content of antimony in the laminated film is attributed to the amount of antimony and the thickness of each layer in the production of each polyester.

  The haze value of the laminated film is preferably 3.0% or less, more preferably 0.2 to 2.5%. This haze value is obtained by dividing the scattered light transmittance by the total light transmittance, and indicates the transparency of the laminated film. For this reason, if the haze value exceeds 3.0%, the scattered light in the laminated film becomes large and the resolution may be lowered. On the other hand, if the haze value is less than 0.2%, it is necessary to reduce the center line average roughness Ra and the maximum height Rt on the surface of the A layer, and the flatness of the surface of the A layer increases, so that the slipperiness of the laminated film is increased. May be reduced, and the winding property may be reduced.

  The photoresist layer constituting the dry film resist is formed of a photosensitive resin material, and is cured by reacting with light such as ultraviolet rays. Specific examples of the photosensitive resin material include alkali-soluble polymers such as carboxylic acid-containing vinyl copolymers, ethylenically unsaturated addition polymerizable monomers such as 2-hydroxy-3-phenoxypropyl acrylate, and light such as benzyldimethyl ketal. A polymerization initiator etc. are mentioned. On the other hand, the protective layer constituting the dry film resist is formed of a polyolefin such as polyethylene or polypropylene, polyester, or the like, and is laminated on the opposite surface of the laminated film in the photoresist layer, thereby protecting the dry film resist.

Next, the manufacturing method of a laminated film and a dry film resist is demonstrated. In the production of the laminated film, the coextrusion method will be described.
When producing a laminated film, first, the polyester for forming the A layer and the polyester for forming the B layer are supplied to separate extruders, heated to a temperature equal to or higher than the melting point of each polyester, and melted. Next, each polyester is extruded as a sheet from a T-die so as to be laminated in the order of A / B / A. Subsequently, the sheet is rapidly cooled to below the glass transition temperature on a rotary cooling drum to obtain an amorphous unstretched film. At this time, in order to improve the flatness of the unstretched film, the adhesion between the unstretched film and the rotating cooling drum may be improved by an electrostatic application adhesion method, a liquid application adhesion method, or the like.

  And a uniaxially stretched film is obtained by extending | stretching an unstretched film in the longitudinal direction (longitudinal stretching) using a roll stretching machine. At this time, the stretching temperature is equal to or higher than the glass transition temperature of the polyester, preferably 70 to 150 ° C, more preferably 75 to 130 ° C. Moreover, 3.0-7 times is preferable and, as for a draw ratio, 3.2-6 times are more preferable. Furthermore, longitudinal stretching may be performed in only one stage, or may be performed in two or more stages. Subsequently, a biaxially stretched film is obtained by extending | stretching a uniaxially stretched film in the transversal direction (lateral stretching) using a tenter stretching machine. At this time, the stretching temperature is preferably 75 to 150 ° C, more preferably 80 to 140 ° C. The draw ratio is preferably 3.2 to 7 times, more preferably 3.5 to 6 times. Further, the transverse stretching may be performed only in one stage, or may be performed in two or more stages.

  Then, a laminated film is manufactured by heat-processing a biaxially stretched film at the temperature of 150-250 degreeC, for example. Here, when the A layer is formed of a low-melting polyester, the temperature in the heat treatment is (T-10) ° C. or higher with respect to the melting point T ° C. of the polyester forming the A layer. It is preferable because the property can be improved. This is because the orientation of the polyester in the A layer is lowered by the melting of the polyester by heat treatment, and voids (voids) formed around the particles by the extinction disappear and are further formed on the surface of the A layer. This is because the shape of the protrusion is steep. When the biaxially stretched film is heat-treated, the biaxially stretched film may be stretched within 30%. Next, a support layer is constituted by the manufactured laminated film, and the support layer and the photoresist layer and the protective layer manufactured according to a conventional method are added in the order of support layer / photoresist layer / protective layer according to a conventional method. A dry film resist is manufactured by laminating.

  When manufacturing an electronic circuit board using a dry film resist, first, for example, a copper layer is laminated on a substrate surface such as an epoxy resin substrate or a glass cloth substrate. Next, after peeling off the protective layer from the dry film resist, the exposed photoresist layer is attached to the copper layer surface. Subsequently, after a glass plate on which a circuit is printed is brought into close contact with the laminated film surface, for example, ultraviolet rays are irradiated from the glass plate side. The irradiated ultraviolet rays are irradiated to the photosensitive resin film after passing through the transparent portion and the laminated film in the circuit image printed on the glass plate. And the location irradiated with ultraviolet rays in the photoresist layer is cured by ultraviolet rays.

At this time, since the center line average roughness Ra is set to 0.002 to 0.030 μm and the maximum height Rt is set to 0.05 to 1.0 μm on the surface of the laminated film, that is, the surface of the A layer, the surface of the laminated film It is possible to improve the adhesion between the glass plate and the glass plate and prevent the formation of bubbles between them. For this reason, the ultraviolet rays that have passed through the glass plate can pass through the laminated film without being scattered by bubbles after passing through the glass plate, and the resolution can be improved. Furthermore, since the number of metal-containing aggregates having a major axis of 10 μm or more is set to 5/10 cm ² or less, the ultraviolet rays transmitted through the glass plate are not shielded by the metal-containing aggregates, and the inside of the laminated film is blocked. Can penetrate. For this reason, it is possible to improve the resolution of the laminated film, and to cure all of the photoresist layer corresponding to the transparent portion in the circuit image printed on the glass plate without generating an uncured portion. it can.

  Subsequently, after removing the glass plate and the laminated film, the uncured portion of the photoresist layer is removed. At this time, removal of the uncured portion of the photoresist layer exposes the corresponding copper layer. Next, the copper layer is etched using acid or the like. At this time, the copper layer exposed by etching is removed from the substrate, and a circuit is formed on the substrate. Then, the electronic circuit board is manufactured by removing the cured photosensitive resin film. At this time, by curing all of the photoresist layer in the portion corresponding to the transparent portion in the image of the circuit printed on the glass plate, the copper layer in the portion corresponding to the circuit is removed by etching. Occurrence can be prevented.

The effects exhibited by the above embodiment will be described below.
-Layer A of the laminated film of this embodiment contains particles having an average particle diameter of 0.01 to 3.0 [mu] m, and has a centerline average roughness Ra of 0.002 to 0.030 [mu] m and a maximum height. The thickness Rt is 0.05 to 1.0 μm, and the number of metal-containing aggregates having a major axis of 10 μm or more in the laminated film is 5/10 cm ² or less. For this reason, generation | occurrence | production of a circuit defect can be prevented more reliably compared with the conventional polyester film by reducing the number in the laminated | multilayer film of the metal containing aggregate resulting from a circuit defect. Furthermore, by setting the average particle diameter of the particles, the centerline average roughness Ra and the maximum height Rt of the surface of the layer A within the above ranges, bubbles are generated between the layer A and the glass plate when the electronic circuit board is manufactured. It is possible to suppress the formation of poor adhesion between the surface of the layer A and the glass plate while suppressing the formation. For this reason, while being able to improve the resolution of a laminated film more, the slipperiness of a laminated film can be improved and the winding-up property can be improved.

  -The content of antimony in the laminated film is preferably 150 ppm or less. In this case, the number of antimony-containing aggregates in the laminated film is reduced, and the rate at which transmitted light is shielded by the antimony-containing aggregates can be reduced, thereby further reliably preventing the occurrence of circuit defects. In addition, the resolution can be further improved.

-The haze value of the laminated film is preferably 3.0% or less. In this case, the resolution can be further improved by improving the transparency of the laminated film.
-Among metal-containing aggregates, we are focusing on antimony-containing aggregates. That is, the number of antimony-containing aggregates having a major axis of 10 μm or more in the laminated film is preferably 5/10 cm ² or less. In this case, the occurrence of circuit defects can be more reliably prevented by reducing the content of the agglomerates containing antimony having a high light shielding property among the metals contained in the metal-containing agglomerates. , The resolution can be further improved.

In addition, this embodiment can also be changed and embodied as follows.
-The laminated film may be formed of two polyester layers by laminating the A layer and the B layer in the order of A / B, or may be formed by laminating four or more polyester layers. Good. At this time, the outermost layer is composed of the A layer. Moreover, you may form a laminated | multilayer film by laminating | stacking A layer, B layer, and a polyester layer (C) in order of A / B / C. At this time, particles may be contained in the polyester (C) layer.

  -You may comprise the said laminated | multilayer film as an unstretched film, and you may comprise as a uniaxially stretched film formed only by longitudinal stretch or horizontal stretch. Further, the laminated film may be formed by simultaneous biaxial stretching in which longitudinal stretching and lateral stretching are simultaneously performed.

  A dry refill resist having the laminated film as a support layer may be used for pattern formation of partition walls of a PDP (Plasma Display Panel). When forming the PDP barrier ribs, first, the protective layer is peeled off from the dry film resist, and then a photoresist layer exposed on the barrier rib material layer surface of the plasma display substrate on which the barrier rib material layer is laminated is pasted. Next, a photomask such as a negative film is brought into close contact with the surface of the support layer and light is irradiated from the photomask side to cure the photoresist layer at a predetermined location, and then the photomask and the support layer are removed and the photo is removed. The uncured portion of the resist layer is removed to form a cured film pattern. Subsequently, the barrier rib material layer exposed between the patterns is etched by sand blasting using the pattern of the hard coating film as a mask to form a predetermined pattern, and then the hard coating film is removed and the remaining barrier rib material layer is baked. By performing the process, the partition wall of the PDP is manufactured. When configured in this way, it is possible to prevent pattern defects from occurring in the pattern of the formed PDP partition walls.

Next, the embodiment will be described more specifically with reference to test examples and comparative examples. First, a measurement method or an evaluation method in each of the following examples will be described.
(1) Layer thickness In each example, a small piece of a film sample was embedded with a resin in which an epoxy resin was mixed with a curing agent and an accelerator, and a slice having a thickness of about 200 nm was prepared using an ultramicrotome. And the microscope picture of the cross section of the obtained section | slice was image | photographed using the transmission electron microscope H-9000 (product name made from Hitachi, Ltd.), and the thickness of each layer was measured from the microscope picture. Here, the acceleration voltage was 300 kV, and the magnification was set in the range of 10,000 to 100,000 times according to the thickness of each layer. Furthermore, the thickness measurement was performed at 50 points, and 10 points from the thicker measurement values and 10 points from the thinner ones were deleted, and 30 points were averaged to obtain a measurement value.

(2) Antimony content of laminated film (Sb amount)
In each example, 2 g of the film sample was decomposed with sulfuric acid + hydrogen peroxide solution to prepare a sample solution. Subsequently, 100 ml of the sample solution was applied to a plasma emission analyzer, and an emission spectrum was measured. And the antimony content was calculated | required from the spectrum intensity | strength of the said emission spectrum using the calibration curve according to the spectrum of the antimony element created beforehand.

(3) Number of antimony-containing aggregates In each example, an optical microscope (magnification 100 times) was used to observe the inside of the laminated film over an area of 50 cm ² , and after marking an aggregate having a major axis of 10 μm or more, scanning type Antimony-containing aggregates were identified using an electron microscope-energy dispersive X-ray analyzer (SEM-EDX), and the number thereof was converted to 10 cm ² .

(4) Surface roughness of layer A surface <Center line average roughness Ra>
In each example, the surface roughness of the A layer surface was measured using a surface roughness measuring device SE-3F (product name, manufactured by Kosaka Laboratory Ltd.). That is, a portion having a reference length L (2.5 mm) is extracted from the film cross-sectional curve in the direction of the center line, the roughness line y = f with the center line of the extracted portion as the x axis and the direction of the vertical magnification as the y axis. When represented by (x), the value obtained by the following formula (1) was defined as the center line average roughness Ra (μm). The measurement was performed on 10 cross-sectional curves, and the average was taken as the measured value. The tip radius of the stylus was 2 μm, the load was 30 mg, and the cutoff value was 0.08 mm.

＜最大高さＲｔ＞
各例において、中心線平均粗さＲａの測定時に得られた断面曲線の抜き取り部分のその平均線に平行な２直線で挟み、この２直線の最大値と最小値の間隔を断面曲線の縦倍率の方向に測定してその値を最大高さＲｔ（μｍ）とした。測定は１０本の断面曲線について行い、それらの平均を測定値とした。

<Maximum height Rt>
In each example, the section of the section curve obtained at the time of measuring the center line average roughness Ra is sandwiched by two straight lines parallel to the average line, and the interval between the maximum and minimum values of the two lines is the vertical magnification of the section curve. The value was measured as the maximum height Rt (μm). The measurement was performed on 10 cross-sectional curves, and the average was taken as the measured value.

(5) Haze value In each example, according to JIS K6741, the turbidity of the laminated film was measured with a spheroid turbidimeter NDH-20D (product name, manufactured by Nippon Denshoku Industries Co., Ltd.), and the haze value was obtained. Value.

(6) Evaluation of practicality of dry film resist A dry film resist was produced using the film of each example. That is, a photoresist layer was applied to the A layer side of the film. However, for Reference Example 3, a photoresist layer was applied to the B layer side of the film. Subsequently, a protective layer of polyolefin film was laminated on the surface of the photoresist layer to produce a dry film resist. Subsequently, the printed circuit was manufactured using the obtained dry film resist. That is, first, the photoresist layer surface of the dry film resist from which the protective layer was peeled was adhered to the surface of the copper layer laminated on the glass fiber-containing epoxy resin plate. Subsequently, a glass plate on which a circuit was printed was brought into close contact with the laminated film surface, and ultraviolet light exposure was performed from the glass plate side. Then, a series of development operations such as washing and etching were performed to form a circuit. And the obtained circuit was observed visually or using a microscope, and while evaluating the circuit defect and the resolution according to the following evaluation criteria, the winding property of the dry film resist was evaluated according to the following evaluation criteria.

<Circuit defects>
Evaluation was made in three stages: no circuit defect was observed (◯), rarely a circuit defect was observed (Δ), a circuit defect occurred, and there was a practical problem (x).

<Resolution>
With extremely high resolution, a clear circuit can be obtained (○), and the sharpness is slightly inferior and the circuit lines are somewhat thick (△). The evaluation was made in three stages of (x) which cannot be used.

<Winding property>
The film has sufficient slipperiness, the winding property is good (○), the film slipping property is slightly insufficient, the winding property is somewhat inferior (△), the film slipping property is insufficient, and the winding property is good Evaluation was made in three stages: (x) where there was a problem.

  Subsequently, the manufacturing method of each polyester is demonstrated. In the following description, the average particle size of the particles was measured by a photographic method using an electron microscope in the case of particles having a uniform particle size and shape. That is, the particle diameter of about 1000 particles was measured and the volume was integrated from the large particle side, and the particle diameter at 50% of the total volume was taken as the average particle diameter. On the other hand, in the case of other particles, the average particle size is the particle size of 50% of the integrated volume distribution in the equivalent spherical distribution measured with a centrifugal precipitation type particle size distribution analyzer SA-CP3 type (product name, manufactured by Shimadzu Corporation). did. The intrinsic viscosity of the polyester was measured at 30 ° C. by dissolving the polyester in 100 ml of a mixed solvent of phenol: tetrechloroethane = 50: 50 (weight ratio). Further, “parts by weight” is indicated by “parts”.

(Polyester A)
In polyester A, first, 100 parts of dimethyl terephthalate, 60 parts of ethylene glycol and 0.09 part of magnesium acetate tetrahydrate were placed in a reactor, and the temperature was raised while heating, and methanol was distilled off to conduct a transesterification reaction. Here, 4 hours from the start of the reaction, the temperature was raised to 230 ° C., and the transesterification reaction was substantially completed.

  Next, 0.1 part of amorphous silica particles having an average particle diameter of 2.0 μm was added as an ethylene glycol slurry. After adding the slurry, 0.03 part of phosphoric acid and 0.013 part of antimony trioxide were further added to carry out a polycondensation reaction to obtain polyester A. Here, the reaction solution was heated and the pressure in the system was decreased, and the polycondensation reaction was stopped 4 hours after the start of the polycondensation reaction. The intrinsic viscosity of polyester A was 0.645 dl / g, and the content of amorphous silica particles in polyester A was 0.10% by mass.

(Polyester B)
In Polyester B, transesterification and polycondensation reactions were performed in the same manner as Polyester A, except that the amorphous silica particles were changed to crosslinked polymer particles and the blending amount of antimony trioxide was changed to 0.0096 parts. It was. The intrinsic viscosity of polyester B was 0.635 dl / g. Table 1 shows the average particle diameter of the crosslinked polymer particles and the content in polyester B.

  Here, the crosslinked polymer particles were prepared by first adding 800 parts of demineralized water to 1.5 parts of potassium persulfate as a water-soluble polymerization initiator and 0.5 parts of lauryl sodium (manufactured by Kao Corporation; EMAL 0) as a dispersion stabilizer. Was added and dissolved uniformly. Next, a mixed solution of 40 parts of styrene, 30 parts of methyl methacrylate and 30 parts of divinylbenzene was added to the solution, and the polymerization reaction was performed at 70 ° C. for 15 hours with stirring in a nitrogen gas atmosphere to obtain substantially spherical particles. . Here, the reaction rate was 98%, and the average particle diameter of the obtained particles was 1.2 μm. Subsequently, the aqueous slurry of particles was cooled to 50 ° C., 1 part of a partially ammonium neutralized product of sodium polyacrylate-methoxypolyethylene glycol-polypropylene glycol monomethacrylate copolymer was added and stirred for 1 hour, and then ethylene glycol 2000. Then, water was distilled off under reduced pressure by heating to obtain crosslinked polymer particles.

(Polyester C and E)
In polyesters C and E, the content of amorphous silica particles in polyester C or E was changed as shown in Table 1. Furthermore, in the polyester C, the amount of antimony trioxide is changed to 0.017 parts, and in the polyester E, the amount of antimony trioxide is changed to 0.036 parts, and the ester exchange is performed in the same manner as the polyester A. Reaction and polycondensation reaction were performed respectively. The intrinsic viscosity of polyester C was 0.657 dl / g, and the intrinsic viscosity of polyester E was 0.664 dl / g.

(Polyester D)
In the polyester D, the average particle diameter of the crosslinked polymer particles and the content in the polyester D were changed as shown in Table 1, and the amount of antimony trioxide was changed to 0.0072 parts, except for the polyester B and Similarly, a transesterification reaction and a polycondensation reaction were performed. The intrinsic viscosity of polyester D was 0.628 dl / g.

(Polyester F and G)
In polyester F and G, the average particle diameter of the amorphous silica particles and the content in polyester F or G were changed as shown in Table 1, respectively. Furthermore, transesterification was carried out in the same manner as for polyester A, except that the blending amount of antimony trioxide in polyester F was changed to 0.017 parts, and the blending amount of antimony trioxide in polyester G was changed to 0.023 parts. Reaction and polycondensation reaction were performed respectively. The intrinsic viscosity of polyester F was 0.640 dl / g, and the intrinsic viscosity of polyester G was 0.653 dl / g.

(Polyester H)
In the polyester H, the transesterification reaction and the polycondensation reaction were performed in the same manner as the polyester A except that the amorphous silica particles were changed to spherical silica particles and the blending amount of antimony trioxide was changed to 0.012 parts. . Polyester H had an intrinsic viscosity of 0.644 dl / g. Table 1 shows the average particle diameter of the spherical silica particles and the content in the polyester H.

As a result of observing these polyesters A and C to H with a microscope, each particle was uniformly dispersed in each polyester.
(Particle-free polyester)
In each non-particle-added polyester that forms the B layer of Test Examples 1 to 4 , Reference Example 3 , Comparative Example 1, Comparative Example 3, and Comparative Example 4, the polyester that forms the A layer of each example except that no particles are added The transesterification reaction and the polycondensation reaction were carried out in the same manner as above. For this reason, the compounding amount of antimony trioxide in each non-particle-added polyester was the same as the polyester forming each A layer, and the intrinsic viscosity of each non-particle-added polyester was 0.630 dl / g.
(Test Examples 1 to 4 , Reference Example 3 and Comparative Examples 1 to 4)
In Test Example 1, the polyester A forming the A layer was first melted using a vented twin screw extruder, and the B layer was formed and the particle-unadded polyester corresponding to the polyester A was separated from the polyester A extruder. Was melted. Next, a co-extruded A / B / A type 2 layer from a T die was immediately cooled to below the glass transition temperature to obtain an amorphous unstretched film. Subsequently, this unstretched film was longitudinally stretched 3.6 times at 93 ° C. using a roll stretcher to obtain a uniaxially stretched film, and then the uniaxially stretched film was 4.2 at 110 ° C. using a tenter stretcher. A biaxially stretched film was obtained by transverse stretching. The biaxially stretched film was heat treated at 220 ° C. for 6 seconds to obtain a laminated film.

In Test Example 2, Test layer 1 except that layer A was formed from polyester B and layer B was formed from a non-particle-added polyester corresponding to polyester B, and the thickness configuration of the laminated film was changed as shown in Table 1. In the same manner, a laminated film was obtained. In Reference Example 3, except that the A layer was formed of polyester C and the B layer was formed of particle-unadded polyester corresponding to polyester C, and the layer configuration and thickness configuration of the laminated film were changed as shown in Table 1. A laminated film was obtained in the same manner as in Test Example 1. In Test Example 4, the same procedure as in Test Example 1 was conducted, except that the A layer was formed from polyester D and the B layer was formed from a non-particle-added polyester corresponding to polyester D, and the thickness configuration was changed as shown in Table 1. To obtain a laminated film.

  In Comparative Example 1, a laminated film was obtained in the same manner as in Test Example 1 except that the A layer was formed from polyester E and the B layer was formed from a non-particle-added polyester corresponding to polyester E. In Comparative Example 2, a polyester film formed of polyester F and having only a single A layer having a layer thickness of 16.0 μm was obtained in the same manner as in Test Example 1 in the longitudinal and lateral stretching. Comparative Example 3 is the same as Test Example 1 except that the A layer is formed of polyester G and the B layer is formed of non-particle-added polyester corresponding to polyester G, and the thickness configuration is changed as shown in Table 1. Thus, a laminated film was obtained. In Comparative Example 4, a laminated film was obtained in the same manner as in Test Example 1 except that the A layer was formed from polyester H and the B layer was formed from a non-particle-added polyester corresponding to polyester H.

About Test example 1-4 , Reference example 3, and Comparative examples 1-4, it measured or evaluated regarding each item of said (1)-(6). The results are shown in Tables 1 and 2. In Table 1, the numerical value of the thickness of each layer is expressed in μm.

表２に示すように、試験例１〜４、参考例３においては、回路欠陥、解像度及び巻取り性について優れた評価となった。一方、表１及び表２に示すように、比較例１及び比較例３においては、アンチモン含有凝集体の個数が５個／１０ｃｍ²を超えているために、回路欠陥が発生し、実用上支障があると評価された。比較例２においては、不定形シリカ粒子の平均粒子径が３．０μｍを超え、中心線平均粗さＲａが０．０３０μｍを超えるとともに最大高さＲｔが１．０μｍを超えているために、解像度が劣り高密度の回路には使用できないと評価された。比較例４においては、中心線平均粗さＲａが０．００２μｍ未満であるとともに最大高さＲｔが０．０５μｍ未満であるために、フィルムの滑り性が不足し、巻取り性に問題があると評価された。

As shown in Table 2, in Test Examples 1 to 4 and Reference Example 3 , the circuit defect, resolution, and winding property were excellent. On the other hand, as shown in Tables 1 and 2, in Comparative Example 1 and Comparative Example 3, the number of antimony-containing aggregates exceeds 5/10 cm ² , so that a circuit defect occurs, which is a practical problem. It was evaluated that there was. In Comparative Example 2, since the average particle diameter of the irregular-shaped silica particles exceeds 3.0 μm, the center line average roughness Ra exceeds 0.030 μm, and the maximum height Rt exceeds 1.0 μm, the resolution However, it was evaluated that it could not be used for high-density circuits. In Comparative Example 4, since the center line average roughness Ra is less than 0.002 μm and the maximum height Rt is less than 0.05 μm, the slipping property of the film is insufficient, and there is a problem in the winding property. It was evaluated.

Further, the technical idea that can be grasped from the embodiment will be described below.
De Lai film and the resist laminated a polyester film support layer, a dry film resist, characterized in that it is formed by laminating a photoresist layer comprising a photosensitive resin material. According to this configuration, it is possible to more reliably prevent the occurrence of a circuit defect and to further improve the resolution.

Claims (2)

A laminated polyester film for dry film resist comprising at least two polyester layers, wherein at least one outermost layer contains particles having an average particle diameter of 0.01 to 3.0 μm, and the center line average roughness of the surface Ra is 0.002 to 0.030 μm and the maximum height Rt is 0.05 to 1.0 μm, and the number of metal-containing aggregates having a major axis of 10 μm or more is 5/10 cm ² or less in the entire polyester layer. der is, containing the metal-containing aggregates antimony, dry film resist laminated polyester film, wherein the content of antimony of the polyester layer overall in is 30～120Ppm. Laminated polyester film for dry film resist according to claim 1 haze value is characterized by der Rukoto 3.0% or less.