JP5343622B2 - Manufacturing apparatus and manufacturing method for sheet with metal compound thin film - Google Patents

Description

  The present invention relates to an apparatus and a method for manufacturing a sheet with a metal compound thin film.

  Conventionally, by depositing a thin film on a sheet exemplified by a plastic film, a metal vapor-deposited film serving as a material for a film capacitor, a magnetic recording tape, a packaging film or the like has been manufactured. For this production, for example, a roll-up type vapor deposition apparatus (for example, Non-Patent Document 1) is used in which a plastic film as a roll is unwound in a vacuum chamber, and is formed again after being formed into a thin film.

  The outline will be described with reference to FIG. FIG. 8 is a diagram showing components of a thin film forming apparatus for continuously forming a thin film on a sheet such as a plastic film. FIG. 8 shows only the main part, and the vacuum chamber and the intermediate roll for housing the structure are omitted. Further, together with FIG. 8, detailed portions such as a gas nozzle are omitted, and FIG. 9 shows an overall schematic diagram showing a vacuum chamber and a vacuum pump.

  In FIG. 9, a long sheet 1 is unwound from a raw roll body 2, and is moved by intermediate rollers 4, 5 on a sheet guide surface 3, which is a surface of a cylindrical metal can that rotates along the traveling direction of the sheet. It is conveyed in a state of being wound from the winding point 33 to the peeling point 32 at a required winding angle determined, and then wound up via the intermediate roller 5 to form a winding roll body 6. When the sheet 1 is conveyed onto the sheet guide surface 3, it is in the crucible 7 (evaporation source) in the region between the film formation start point 30 and the film formation end point 31 restricted by the traveling direction mask 11b. The vapor 10 evaporated from the vapor deposition material 8 adheres to the sheet 1, and a thin film 13 is formed on the sheet 1. The evaporation includes, for example, a method of heating the vapor deposition material using the principle of induction heating or resistance heating, and a method of heating the vapor deposition material by irradiating the vapor deposition material. The sheet guide surface 3 mainly has a role of conveying the sheet 1 without wrinkles and a role of efficiently releasing the heat load received by the sheet 1. For this reason, for example, it is controlled to a required temperature by temperature control by circulation of a known heat medium. In addition, not only a cylinder but also a method of conveying a sheet on a belt body can be seen.

  As a method of forming a metal compound thin film using such a thin film forming apparatus, a metal vapor deposition material is melted and evaporated, and a reaction gas such as oxygen is introduced on the way to form a metal compound thin film on a sheet. The method is known.

  For example, as a film with a metal oxide thin film, a film with a thin film of aluminum oxide or silicon oxide has been proposed in the field of packaging films having excellent gas barrier properties (for example, Patent Documents 1 and 2). In particular, in the vapor deposition of aluminum oxide, a method is generally used in which metal aluminum is heated and evaporated, and oxygen is introduced into the metal vapor atmosphere to form an oxide film. In such a packaging film with a metal oxide thin film, a method of forming a metal oxide film of about 5 to 30 nm on a plastic film is proposed. Further, in the method of obtaining a metal oxide film of a material mainly composed of Co, CoNi, and Fe as a ferromagnetic material used for a magnetic recording material, in order to improve magnetic characteristics, a metal is partially applied in the film thickness direction. A method of oxidizing a metal or obtaining a metalloid oxide is disclosed (for example, Patent Document 3). Further, a reinforcing film made of a metal material selected from metals, metalloids and alloys, and oxides and composites thereof is formed on one or both sides of a plastic film, and this is used as a support for a magnetic recording medium. It has been proposed (for example, Patent Documents 4 and 5).

  Thus, various forms are employ | adopted for the sheet | seat with a metal compound thin film according to the objective. If the gas barrier property is aimed, a sufficient function can be exhibited at a film thickness of about 5 to 30 nm. If the magnetic property of the magnetic recording material is aimed, it is partially in the film thickness direction of a thin film having a film thickness of 50 to 300 nm. Sufficient characteristics can be obtained by oxidizing to.

  However, when increasing the strength of the support as a reinforcing film for a support for magnetic recording media, the metal oxide thin film may have to be thick (for example, about 50 to 300 nm). With such a thick film, there is a problem that it is difficult to uniformly oxidize the metal in the thickness direction of the thin film and in the sheet width direction. Further, such a magnetic recording medium support is required to be produced at a low cost, and although it is necessary to perform evaporation with the amount of evaporation and the amount of introduced oxygen increased at the highest possible rate, In this case, it becomes difficult to ensure the film thickness and the thin film uniformity in the width direction. In order to solve such a problem, a method for forming a metal oxide with high oxidation reaction efficiency that can oxidize the entire thin film in the thickness direction, particularly at the end in the sheet width direction, is required.

  Here, conventionally, several techniques have been proposed as a method of introducing oxygen for forming a metal compound, particularly a metal oxide thin film.

  For example, in Patent Document 6, aluminum is used as a metal material, and the amount of oxygen introduced into the atmosphere of aluminum vapor is 1.0% of the amount of aluminum vapor relative to the amount of aluminum vapor generated by heating aluminum. A method is disclosed in which an amount of oxygen necessary and sufficient for the reaction between metal vapor and oxygen is supplied by adjusting within a range of ˜1.5 times.

  Patent Document 2 discloses that aluminum is used as a metal material, the amount A (mol / min) of aluminum vapor generated per unit time by heating the aluminum material, and the amount B (mol / mol) of oxygen introduced per unit time. And the amount B of oxygen is adjusted so that the ratio B / A to 0.1 ≦ B / A <0.3 is maintained. It is said that a transparent aluminum oxide film having desired oxygen permeability, water vapor permeability, and total light transmittance can be obtained by this method of adjusting the amount of oxygen.

  However, in the method of adjusting the amount of oxygen to be introduced according to the amount of metal vapor generated as in the prior art, there may be a problem that the film thickness at the end in the sheet width direction becomes thinner than at the center. That is, the width of the crucible in the sheet width direction is generally 1 to 1.5 times the film formation width, but the thickness of the thin film formed at each position in the sheet width direction is It is influenced not only by the position just below the position but also by the amount of steam coming from diagonally below. However, there are few vapor components flying from the lower edge of the sheet. Therefore, the film thickness tends to be thinner at the end in the sheet width direction than at the center.

  On the other hand, in order to make the amount of the metal vapor reaching the sheet uniform in the sheet width direction, it is possible to increase the width of the crucible to 1.5 times or more the film forming width. However, with this method, the amount of metal vapor that does not adhere to the sheet increases, and the use efficiency of the metal material also deteriorates. Further, when the crucible width is increased, the energy required for evaporating the material increases.

  Further, when the amount of evaporation at the sheet width direction end of the crucible is increased to compensate for the film thickness at the sheet end, in the vicinity of the evaporation source or in the intermediate area between the evaporation source and the sheet, the center portion in the sheet width direction The metal vapor density is high at the end. If oxygen gas for the oxidation reaction is introduced there, the metal vapor diffuses to the outside with a low density, and as a result, the film thickness at the end may be thinner than at the center. Specifically, in the embodiment shown in FIG. 8, for example, when a metal compound thin film is to be formed with a length of 1000 [mm] or more in the width direction, the end of the opening 12 of the width direction mask corresponding to the film formation region of the sheet. In the range of 150 [mm] from the inner part, the phenomenon that the film thickness was partially reduced was remarkable. When manufacturing a sheet with a long thin film by a conventional winding type vapor deposition apparatus, it is common to provide an undeposited band that does not form a thin film about 5 to 30 [mm] from the end of the sheet. Moreover, the end face irregularity phenomenon generated in the winding roll body may occur, and the range of 10 to 30 [mm] from the end of the sheet is removed from the product in the slit process after the vapor deposition process, including the previously undeposited zone. It is common. However, as described above, if there is a problem that the film thickness becomes thin in the range of about 150 [mm] from the edge of the sheet, it is necessary to remove the edge with a width wider than 30 [mm], and the yield of the product Will be dropped.

  In particular, when a metal compound thin film is continuously formed on a long sheet, there is a difference in the diameter of the take-up roll body at the center and the end in the sheet width direction of the wound sheet roll with thin film. End up. For example, when an aluminum oxide thin film is vapor-deposited with a film thickness of 100 [nm] on a plastic film of 5 [μm], the film thickness at the end may cause a difference of 10 to 20 [nm] compared to the central part. When the length of 10,000 [m] is vapor-deposited and wound around the core with this difference in film thickness, the diameter of the take-up roll body has a difference of about 120 to 250 [μm] in the sheet width direction. However, if this difference is large, wrinkles are generated in the circumferential direction of the winding roll body. In addition, in the process of performing dry coating and wet coating while rewinding the sheet under high tension using this winding roll body, the curvature in the sheet width direction caused by the diameter distribution in the width direction described above occurs, It may cause uneven coating. In particular, when such a difference in diameter of the winding roll body extends to the center in the roll body width direction, specifically, a difference of 100 [μm] or more on the inner side from the position of 100 [mm] from the end. When this occurs, the above-mentioned wrinkles and curvature during conveyance become significant. Thus, secondary defects such as wrinkles may occur due to the decrease in the film thickness at the end.

  In Patent Document 7, a vapor diffusion control means for regulating and controlling the diffusion direction of the vapor flow is provided immediately above the evaporation source, and oxygen gas is blown toward the vapor flow scattered through the vapor diffusion control means. Thus, a method has been disclosed in which metal vapor from a crucible is efficiently deposited on a sheet to form a film. However, even in this method, when the film thickness is increased or the speed is increased, the introduced oxygen and the metal vapor are in an overcrowded state at the position where the metal vapor has passed through the vapor diffusion control means and diffused to the outside. The film thickness at the end may be reduced. In Patent Document 8 and Patent Document 9, a deposition cylinder is provided between the evaporation source and the sheet guide surface so as to extend in a cylinder shape in the evaporation direction, and the angle at which the metal vapor enters the sheet is regulated. A method for improving the gas barrier property and improving the holding power of the magnetic material deposited film is disclosed. However, in this case, the metal vapor adhering to the sheet is limited, and the use efficiency of the evaporation material may be lowered. Along with the reduction in efficiency, it is necessary to reduce the speed or increase the input power to the evaporation source in order to obtain a target film thickness, which may deteriorate productivity and production cost.

  As described above, in the prior art, a thick film (for example, a thickness of 50 to 300 nm) having the same thickness at the end portion and the center portion in the sheet width direction and being uniformly oxidized is formed at high speed. It was difficult.

JP-A-62-103359 JP 2001-192808 A JP-A-62-275316 JP 2003-129229 A JP 2007-226943 A Japanese Patent Laid-Open No. 10-046323 JP-A-10-105965 JP-A-6-306607 Japanese Patent Laid-Open No. 6-111295

Ken Ihouchi et al., “Polymer films and functional membranes”, Gihodo Publishing, April 1991, p. 198-203

  In view of the above-mentioned problems of the prior art, the present invention provides a metal compound thin film sheet that reacts uniformly with a metal and a reactive gas and has a uniform film thickness in the sheet width direction even at a high speed. It is an object to provide an apparatus and method that can be manufactured.

The present invention for achieving the above object is characterized by any one of the following configurations (1) to (10).
(1) A sheet guide surface that conveys the sheet while being in contact with the sheet, a conveying unit that conveys the sheet as the sheet guide surface moves, and a metal toward the sheet on the sheet guide surface An evaporation source that disperses the vapor; a reaction gas introduction unit that introduces a gas to react with the metal vapor; and a mask that limits a region where the metal vapor reaches the sheet, and is continuous with the conveyed sheet. An apparatus for manufacturing a sheet with a metal compound thin film that forms a metal compound thin film in a linear direction connecting the evaporation source and the sheet guide surface, from the gas introduced by the reaction gas introduction means and the evaporation source A metal compound comprising a diffusion preventing means for preventing the metal vapor from diffusing outside in the sheet width direction at a position where the metal vapor that has come in is mixed. Apparatus for manufacturing a thin film with a sheet.
(2) The diffusion preventing means is a pair of wall-shaped structures, and the wall-shaped structures project inward from the sheet width direction end of the evaporation source. The manufacturing apparatus of the sheet | seat with a metal compound thin film of description.
(3) If the shortest distance between the sheet guide surface and the evaporation source is D [m], the length of the wall-like structure is 0.5D with respect to the linear direction connecting the evaporation source and the sheet guide surface. It is [m] or more, The manufacturing apparatus of the sheet | seat with a metal compound thin film as described in said (2) characterized by the above-mentioned.
(4) When the length of the opening of the mask in the sheet width direction is A [m] and the shortest distance between the pair of wall-like structures is C [m], the following equation is satisfied: The manufacturing apparatus of the sheet | seat with a metal compound thin film as described in said (2) or (3).
A <C ≦ 1.2A
(5) The reaction gas introduction means has a gas introduction port at a position where the wall-like structure exists in a linear direction connecting the evaporation source and the sheet guide surface, (2) The manufacturing apparatus of the sheet | seat with a metal compound thin film in any one of (4).
(6) The diffusion preventing means is a gas supply means and a wall-like structure, and the wall-like structure is provided outside the gas supply means in the sheet width direction. )-(5) The metal compound thin film forming apparatus in any one of.
(7) Using the apparatus according to any one of (1) to (6), metal vapor is allowed to fly from the evaporation source toward the sheet, and at the same time, gas is introduced into the metal vapor, and the sheet A method for producing a sheet with a metal compound thin film, comprising continuously forming a metal compound thin film thereon.
(8) The metal is aluminum, the gas is oxygen, the metal compound thin film is an aluminum oxide film, and the deposition rate of the aluminum oxide film is 400 [nm / sec] or more. The manufacturing method of the sheet | seat with a metal compound thin film as described in said (7).
(9) The method for producing a sheet with a metal compound thin film according to (8), wherein the thickness of the metal compound thin film is in a range of 50 to 300 [nm].
(10) A method for producing a sheet with a double-sided metal compound thin film, wherein a metal oxide thin film is formed on both sides of the sheet by the method described in any of (7) to (9) above.
(11) A thin film film in which a metal compound thin film having a film thickness of 50 [nm] or more is formed on at least one surface of a plastic film having a thickness of 10 [μm] or less and a film width W [mm] of 1000 [mm] or more. A film roll body obtained by winding a film with a core around a core, and a range having a roll body diameter having a difference from the roll body maximum diameter within 100 [μm] with respect to the film width direction per winding length of 10000 [m]. The film roll body with a metal compound thin film characterized by existing continuously over W-100 [mm].

  Here, as a typical sheet applied in the present invention, there are sheets such as a plastic film and paper. In particular, a plastic film is preferably used in the present invention. Examples of the material of the plastic film include polyolefins such as polyethylene and polypropylene, and polymer plastic films such as polyester, polycarbonate, polyimide, polyphenylene sulfide, aramid, and nylon. The plastic film may be a single layer or a laminate film having two or more layers. Moreover, as a sheet | seat applied to this invention, metal foil may be sufficient and copper foil, aluminum foil, stainless steel foil etc. can be illustrated.

    In the present invention, examples of the method for forming the metal compound thin film include a vacuum deposition method and an ion plating method. Among these, the vacuum evaporation method is preferable because high-speed film formation with a film formation rate of several hundreds [nm / second] is possible. In the evaporation source of the vacuum evaporation method, as a method of heating the material, there are a resistance heating method and an electron beam heating method in addition to the induction heating method, and any of them can be applied. In particular, the electron beam heating method is the most suitable method for obtaining a uniform metal compound thin film in the width direction because the evaporation amount can be easily controlled in the sheet width direction.

    In the present invention, the “evaporation source” refers to a volume portion that melts a metal material that is a thin film material. A container for storing a metal material, a heat insulating material, a material supply device, a heater for heating, and the like are disposed around the evaporation source. A suitable one is appropriately selected depending on the method of heating the evaporation source. There is no particular limitation.

In the present invention, the “film formation rate” refers to a speed at which the metal compound is deposited on the sheet surface in the sheet film formation region. Specifically, the sheet conveyance speed is v [m / sec], the sheet When the film thickness of the metal compound thin film deposited on the surface is d [nm] and the length of the sheet film formation region in the sheet conveyance direction is L [m], it indicates a value represented by the following formula.
(Film formation rate) [nm / sec] = (v × d) / L (i)
In the present invention, the “sheet guide surface” refers to a constituent element of a thin film forming apparatus that conveys a sheet while contacting a surface opposite to the thin film forming surface of the sheet when a thin film is formed on the sheet. This “sheet guide surface” mainly serves to convey the sheet without wrinkles and to efficiently release the heat received by the sheet. A typical one is a cylindrical one as shown in FIG. 1 described later, and conveys a sheet while rotating about an axis. In addition, not only the cylindrical shape but also a method of conveying a sheet on a belt body is known, but any one is effective in the present invention.

  In the present invention, “the position where the gas introduced by the reaction gas introducing means and the metal vapor flying from the evaporation source are mixed in the linear direction connecting the evaporation source and the sheet guide surface” means an oxygen nozzle When the direction of the opening of the reaction gas introduction means such as the above is perpendicular to the linear direction or toward the sheet guide surface, it means a range from the opening to the sheet guide surface with respect to the linear direction. Further, when the direction of the opening of the reaction gas introducing means such as the oxygen nozzle is directed toward the evaporation source with respect to the linear direction, it means a range from the evaporation source to the sheet guide surface with respect to the linear direction.

  In the present invention, a metal material is evaporated and a reactive gas such as oxygen is introduced into the vapor atmosphere to provide a metal compound thin film. The metal material is not particularly limited as long as the desired properties are obtained. A material mainly composed of aluminum and / or copper is preferably used because it has a low melting point and is an inexpensive material. Aluminum oxide films and copper oxide films are preferably used because of their good properties such as gas barrier properties, rigidity, thermal expansion properties, and productivity. Examples of other materials include metals such as Zn, Sn, Ni, Ag, Co, Fe, Mn, Mg, In, and Ti. Among these materials, there are materials such as Sn, Mg, In, etc. in which oxides have semiconductor performance, or alloy materials thereof, but these are appropriately selected depending on the use of the sheet with a thin film, The application of the present invention is not limited. Further, a metal oxide using oxygen as a reaction gas is typical, but it can also be applied to a metal nitride using nitrogen, or a metal carbide using a carbon dioxide gas or an organic gas.

  According to the present invention, as is clear from the comparison between Examples and Comparative Examples described later, even if the metal compound thin film is relatively thick, for example, 50 to 300 [nm], a uniform metal compound thin film is formed with a sheet width. A sheet with a metal compound thin film having a substantially constant film thickness over the direction can be produced.

It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is a schematic block diagram of the winding-type vacuum evaporation system which shows one embodiment of the manufacturing apparatus of this invention. It is the schematic block diagram which showed an example of the conventional winding type vacuum evaporation system. It is the schematic block diagram which showed an example of the conventional winding type vacuum evaporation system. 4 shows the composition analysis result in the thickness direction of the aluminum oxide film formed in Example 1. FIG. It is a compositional analysis result of the thickness direction of the aluminum oxide film formed in Example 2. 3 is a composition analysis result in a thickness direction of the aluminum oxide film formed in Comparative Example 1. FIG. It is a schematic block diagram of the winding type vacuum evaporation system which shows an example of the position which provides a vapor | steam diffusion prevention wall. It is a schematic block diagram of the winding type vacuum evaporation system which shows an example of the position which provides a vapor | steam diffusion prevention wall. It is a schematic block diagram of the winding type vacuum evaporation system which shows an example of the position which provides a vapor | steam diffusion prevention wall. It is a schematic block diagram of the winding type vacuum evaporation system which shows an example of the position which provides a vapor | steam diffusion prevention wall. It is a figure which shows the diameter distribution of the width direction of the roll body of the film with an aluminum oxide film obtained in Example 1. FIG. It is a figure which shows the diameter distribution of the width direction of the roll body of the film with an aluminum oxide film obtained in Example 2. FIG. It is a figure which shows the diameter distribution of the width direction of the roll body of the film with an aluminum oxide film obtained by the comparative example 1. FIG.

  Hereinafter, taking the case of applying the example of the best embodiment of the present invention to a wind-up type vapor deposition apparatus as an example, it is a drawing about the formation of a metal oxide thin film typically deposited by reacting oxygen and metal with a metal compound. The description will be given with reference.

  FIG. 1 is a schematic configuration diagram of a wind-up type vapor deposition apparatus showing one embodiment of the production apparatus of the present invention, showing only main parts, and vacuum chambers, intermediate rolls, raw roll bodies and vapor depositions that contain structures. The roll body is omitted. FIG. 2 is a schematic cross-sectional view of the apparatus viewed from the left hand of FIG. Note that components having the same or equivalent functions as those of the conventional example are denoted by the same reference numerals, and detailed description thereof is omitted.

  The take-up type vapor deposition apparatus shown in FIG. 1 has a sheet guide surface 3 that conveys the sheet 1 while being in contact with the sheet 1, and a cylindrical metal that conveys one sheet as the sheet guide surface 3 moves. A conveying means such as a can made and a crucible 7 (evaporation source) for scattering metal vapor toward the sheet 1 on the sheet guide surface 3 are provided. Between the sheet guide surface 3 and the crucible 7 is provided oxygen introducing means (reactive gas introducing means) for introducing oxygen for oxidation reaction with metal vapor, and metal particles fly on the surface of the sheet 1. The width direction mask 11a is provided so as to limit the region and prevent the metal vapor from adhering to an extra place. Further, the height of the mixture of the metal vapor and oxygen between the width direction mask 11a and the crucible 7 (that is, from the oxygen introduced by the oxygen introduction means and the evaporation source in the linear direction connecting the sheet guide surface and the evaporation source). A pair of vapor diffusion prevention walls 20 (wall-like structures) for preventing the metal vapor from diffusing outside in the sheet width direction is provided at the end in the sheet width direction at the position where the metal vapor that has come in is mixed. It has been. The oxygen introducing means includes a plurality of introduction pipes 15 arranged in the sheet width direction, and the plurality of introduction pipes 15 have an oxygen introduction port at a position where the vapor diffusion prevention wall 20 exists in the vertical direction of the figure. It is arranged to be located.

  In such an apparatus, as shown in FIG. 2, a long sheet 1 is continuously drawn out from an original roll body 2 and is rotated on the surface of a cylindrical metal can that rotates along the traveling direction of the sheet. A sheet guide surface 3 is conveyed in a state of being wound from a winding point 33 to a peeling point 32 at a required winding angle determined by the intermediate rollers 4 and 5, and then wound around the intermediate roller 5 to be wound into a winding roll body. 6 is formed.

  At this time, the vapor deposition material 8 in the crucible 7 is evaporated, and at the same time, oxygen is introduced into the region of the metal vapor 10 evaporating from the crucible 7 through the introduction tube 15. As a result, when the sheet 1 is conveyed onto the sheet guide surface 3, the deposition in the crucible 7 is performed in the region between the film formation start point 30 and the film formation end point 31 limited by the traveling direction mask 11 b. Vapor 10 evaporated from the material 8 adheres to the sheet 1 and a thin film 13 is formed on the sheet 1. The thin film 13 is formed of metal by oxygen introduced into the region of the metal vapor 10 from the introduction pipe 15. It becomes an oxide. That is, a metal oxide thin film 13 is formed on the surface of the sheet 1.

  In addition, as a method of melting and evaporating a metal, for example, a high-frequency induction heating method in which a deposition material is heated using the principle of induction heating or resistance heating, a resistance heating method, or heating by irradiating the deposition material with an electron beam. There is an electron beam method. In order to increase the thickness of the metal oxide film, a high frequency induction heating method or an electron beam method is preferably used, and an electron beam method is preferably used if it is a high melting point material, for example, a melting point material of 1500 [° C.] or higher.

  Further, the sheet guide surface 3 mainly has a role of conveying the sheet 1 without wrinkles and a role of efficiently releasing the heat load received by the sheet 1. For this reason, for example, it is controlled to a required temperature by temperature control by circulation of a known heat medium. Specifically, it is cooled to, for example, about −20 [° C.] using a refrigerant such as ethylene glycol or silicone oil. In addition, a method of conveying a sheet on a belt body is also applicable, not limited to a cylinder.

  The metal oxide thin film may be formed only on one side of the sheet, but by forming on both sides of the sheet, for example, a sheet having strength and dimensional stability that can be used for a base film for a magnetic tape, Become.

  Such a significant difference between the present invention and the prior art described in FIG. 8 is that, in the present invention, for example, as shown in FIGS. 1 and 3, the metal vapor between the sheet guide surface 3 and the crucible 7 The point is that a vapor diffusion preventing wall 20 for preventing the metal vapor from diffusing outside in the sheet width direction is provided at a region height where a reaction gas such as oxygen is mixed.

  For example, when a metal oxide thin film having a thickness of 50 [nm] or more is formed at a sheet conveyance speed of 150 [m / min] or more, the metal vapor density from the evaporation source is relatively high. In the case of evaporating a metal with such a high vapor density, in general, the vapor easily diffuses to the outside immediately above the crucible having a lower pressure due to the difference between the pressure just above the crucible 7 and the pressure at the other part. Become. In particular, immediately above the crucible 7, there is a low-pressure space in the region outside the sheet width direction end, and the metal vapor is relatively easy to diffuse, so that it is difficult for the metal vapor to deposit particularly at the width direction end of the sheet. . However, in the present invention, by providing a vapor diffusion prevention wall that prevents the metal vapor from diffusing outside in the sheet width direction, the metal vapor can be prevented from diffusing to a region that does not contribute to the formation of the thin film. The metal oxide can be deposited on the sheet with substantially the same efficiency at the center and the end in the sheet width direction.

  The vapor diffusion prevention wall 20 is arranged in the height direction in a region where oxygen introduced by the introduction pipe 15 serving as oxygen introduction means and metal vapor flying from the crucible 7 coexist. Oxygen released from the opening 16 of the introduction tube 15 flies along the direction of the introduction tube 15. The oxygen which flies flies to the surface of the sheet 1 on the sheet guide surface 3 while colliding with the metal vapor coming from the crucible 7 or reacting with the metal vapor, and a metal oxide thin film is formed. Therefore, the region where the metal vapor and oxygen are mixed here refers to the region from the region where oxygen and metal vapor collide to the surface of the sheet 1 on the sheet guide surface 3.

  Further, the arrangement in the sheet width direction of the vapor diffusion prevention wall 20 is the both ends of the metal vapor in the sheet width direction, that is, the both ends of the metal vapor region flying between the evaporation source and the sheet guide surface. . Specifically, such a region is a region between the width direction mask 11a and the crucible 7 in the sheet width direction, and at least a part of the vapor diffusion prevention wall 20 is substantially evaporated of the metal of the crucible 7. It is preferable to exist inside the width and outside the opening 12 of the mask. More preferably, as shown in FIG. 1, it is preferable that the pair of vapor diffusion prevention walls 20 protrude inward from the sheet width direction end of the crucible 7 as an evaporation source.

  Specifically, with respect to the sheet width direction, when the opening width of the mask is A [m] and the distance (shortest distance 22) between the pair of vapor diffusion prevention walls 20 shown in FIG. It is preferable to satisfy the relationship of C ≦ 1.2A. In addition, assuming that the width in which the metal is substantially evaporated is B [m], B is in a range satisfying A ≦ B ≦ 1.5 × A, and C is A ≦ C ≦ B It is desirable to be within the range. When B exceeds 1.5 A, the film thickness at the end in the sheet width direction is unlikely to decrease, but the metal material adhering to the mask or the like increases, and the use efficiency of the material deteriorates. More preferably, as shown in FIG. 1, a form in which the pair of vapor diffusion prevention walls 20 projects inward from the sheet width direction end portion of the crucible 7 serving as an evaporation source is preferable. Providing such an overhanging portion makes it difficult for metal vapor and oxygen gas to diffuse near the surface of the sheet 1 to be formed, and is more effective in efficiently uniforming the thickness of the end portion. The overhanging portion is located closest to the sheet guiding surface between the crucible 7 and the sheet guiding surface 3, and the distance between the overhanging portions of the vapor diffusion preventing walls 20 at both ends, that is, the vapor diffusion preventing walls provided at both ends. The shortest distance C [m] is preferably in the range of A ≦ C ≦ 1.2A as described above. If the shortest distance C of the vapor diffusion prevention wall is smaller than the opening width A of the mask, the amount of vapor adhering to the sheet may be hindered. On the other hand, if it is larger than 1.2 A, the metal vapor and oxygen gas that do not adhere to the sheet increase, which may be disadvantageous in terms of the efficiency of use of the metal material and the amount of oxygen introduced.

  Further, in the linear direction connecting the sheet guide surface 3 and the crucible 7, it is desirable that the range where the vapor diffusion prevention wall 20 exists occupies 50% or more of the shortest distance D between the sheet guide surface and the evaporation source. In the case of less than 50%, metal vapor or oxygen diffuses between the vapor diffusion prevention wall 20 and the width direction mask 11a and / or the gap between the vapor diffusion prevention wall 20 and the crucible 7 to the outside in the sheet width direction. As a result, the film thickness at the end in the sheet width direction may be thinner than the center.

In addition, the width | variety in which the metal has substantially evaporated refers to the width | variety of the area | region which has supplied the energy for evaporation with respect to the vapor deposition material 8 in the crucible 7. FIG. For example, in the case of evaporating with an electron gun, it refers to a region where a metal material in a crucible is irradiated with an electron beam. By disposing the pair of vapor diffusion prevention walls 20 on the inner side of the evaporated width, the low pressure region can be reduced as much as possible. Making the vapor diffusion prevention wall 20 outside the opening 12 of the width direction mask 11a means that there is no structure other than the width direction mask 11a and the metal vapor 10 is deposited on the sheet 1, and the opening 12 It can be said that it is a structure in which it is easy to obtain a more uniform film thickness distribution within the range. The width direction mask 11a and the vapor diffusion prevention wall 20 may be an integral structure.
In addition, in order to react a metal vapor having a high vapor density as described above with oxygen and to form a thin film having a uniform oxidation degree in the thickness direction of the thin film, it is necessary to introduce oxygen uniformly into the metal vapor region. There is. According to the knowledge of the present inventors, a tubular shape is formed toward the region between the crucible 7 and the sheet guide surface 3 as shown in FIG. It is suitable to provide an introduction tube 15 having a tip. Further, in order to form a metal oxide thin film having a uniform oxidation degree in the thickness direction of the thin film, it is preferable to arrange the introduction pipes 15 on both the upstream side and the downstream side in the sheet conveyance direction of the evaporation source. In order to obtain a metal oxide thin film having a uniform oxidation degree in the sheet width direction, it is preferable to arrange a plurality of introduction pipes 15 in the sheet width direction. However, when oxygen gas is introduced into the metal vapor region with such an introduction pipe, the metal vapor and oxygen gas are mixed, the density of gas particles is increased, and the gas is easily diffused to the outside. Therefore, it is preferable to arrange a vapor diffusion prevention wall in a region where oxygen and metal vapor coexist. At this time, the vapor diffusion prevention wall 20 is located at a position 100 where the opening 16 of the introduction pipe exists (for example, FIG. 13 and FIG. 14) with respect to the linear direction connecting the crucible 7 serving as the evaporation source and the sheet guide surface 3. It is preferable to arrange it on the side of the introduction pipe facing the opening 16 (for example, FIGS. 15 and 16).

  Furthermore, the vapor diffusion prevention wall 20 preferably does not regulate the incident angle of the metal vapor 10 on the sheet 1. That is, it is preferable that there are parallel wall surfaces in the traveling direction of the seat, but no substantial wall surface exists in the direction intersecting the traveling direction of the seat. The vapor diffusion prevention wall having a wall surface in a direction crossing the traveling direction of the sheet lowers the adhesion efficiency of the metal vapor 10 to the sheet 1 and hinders high-speed film formation that is the object of the present invention. May end up. In addition, according to the knowledge of the present inventors, particularly in the case of vapor deposition of a metal compound that introduces a gas and reacts with the metal vapor 10, for example, if four sides are surrounded by a vapor diffusion prevention wall, the vapor or gas is contained inside the vapor diffusion prevention wall. It may stay and hinder evaporation of the metal vapor 10 from the evaporation source 7, resulting in a decrease in the film formation rate. Therefore, the vapor diffusion prevention wall having a substantial wall surface in the direction intersecting the sheet traveling direction is not provided, and the metal vapor is discharged by exhausting excess metal vapor or gas that has not been used for film formation with a vacuum pump. It is preferable to fly efficiently in the direction of the sheet guide surface. In the present invention, the vapor diffusion prevention wall 20 at the end in the sheet width direction is installed for the purpose of averaging the ease of diffusion of the metal vapor 10 and the introduced gas in the sheet width direction, and its meaning. But a wall that intersects the direction of seat travel is not necessary.

  In the present invention, a pair of gas supply means may be provided as the diffusion preventing means instead of the pair of vapor diffusion preventing walls. That is, by introducing the gas into the sheet width direction both ends of the metal vapor evaporating from the crucible, the pressure in the region outside the region where the metal is substantially evaporated increases, and the metal vapor 10 evaporating from the crucible 7 Since it becomes difficult to diffuse outside, the same effect as the case where a vapor diffusion prevention wall is provided can be obtained. Specifically, for example, as shown in FIG. 4, vapor diffusion preventing gas nozzles 21 are provided at both ends in the sheet width direction of the crucible 7 toward the upper width direction mask 11 a or the sheet 1 on the sheet guide surface 3. . By doing so, gas particles are present also outside the metal vapor region, and there is an effect of preventing both from colliding and diffusing the metal particles to the outside. In the case of depositing a metal oxide thin film, the vapor diffusion preventing gas is preferably oxygen that reacts with metal vapor to become metal oxide, or rare gas such as helium or argon that does not react with metal vapor.

  And, as shown in FIG. 5, in the case of using a pair of vapor diffusion prevention walls 20 and a pair of gas supply means (vapor diffusion prevention gas nozzle 21) in combination, the vapor is less likely to diffuse outward, Since the amount of metal vapor deposited on the vapor diffusion prevention wall 20 is reduced, it is possible to reduce the trouble of removing the deposited metal on the vapor diffusion prevention wall 20. In this case, the vapor diffusion prevention wall 20 is preferably provided outside the vapor diffusion prevention gas nozzle 21 in the sheet width direction.

  In the present invention, the metal vapor is blown from the evaporation source toward the sheet by the apparatus and method as described above, and at the same time, a reactive gas such as oxygen is introduced into the metal vapor, and the metal compound thin film is continuously formed on the sheet. As the metal, the above-described materials can be used, and it is particularly preferable to form a thin film of an aluminum oxide film using aluminum.

  Furthermore, the present inventors have found that when forming a metal oxide thin film such as an aluminum oxide film, the optimum metal vapor density that exerts the effect of preventing vapor diffusion, the size of the evaporation source, and the size of the film formation region of the sheet It was investigated. As a result, the film thickness at the end in the sheet width direction is the film thickness at the center when there is no anti-diffusion measure under the film forming conditions where the film forming rate of the metal oxide thin film is 400 [nm / sec] or more. It has been found that there is a case where a phenomenon of 5% or more decrease is observed. This level is a level at which the outer shape of the wound product when the sheet is wound is recognized as a significant difference between the end portion and the center portion in the width direction, and suitable for exhibiting the effect of the vapor diffusion preventing means in this respect. It can be said that it is a target. More preferably, the metal oxide thin film is preferably applied in the range of 600 to 1000 [nm / second]. When the film formation rate is higher than 600 [nm / sec], a phenomenon is observed in which the film thickness at the end in the sheet width direction is reduced by 10% or more compared to the film thickness at the center. Even one sheet is a level that is recognized as a significant difference between the central part and the end part in the width direction in the film thickness and the physical properties of the thin film, and can be said to be a more suitable target exhibiting the effect of preventing vapor diffusion. On the other hand, when the film formation rate exceeds 1000 [nm / second], the density of the metal vapor or oxygen gas may become excessively high and the pressure in the film formation chamber may increase.

  In the present invention, it is difficult to form a uniform oxidation degree in the film thickness direction, and in the film formation with a relatively large film thickness, the physical properties of the thin film in the sheet width direction, such as the gas barrier property and the rigidity of the thin film, to the end. This is particularly effective in terms of uniform expression, and is specifically suitable for forming a metal oxide thin film having a thickness of 50 [nm] or more. On the other hand, when the film thickness is larger than 300 [nm], the incident angles of the metal vapor and the reactive gas incident on the sheet are biased particularly at the end in the sheet width direction due to the influence of the width direction mask 11a and the vapor diffusion preventing means. The physical properties of the thin film may be different between the central portion and the end portion, and the effect of the present invention becomes thin and cannot be said to be a suitable target.

  Further, as a parameter of the rate at which the metal oxide thin film is deposited, a parameter called a dynamic rate [nm · m / min] obtained by multiplying the sheet conveyance speed [m / min] and the film thickness [nm] of the thin film is used. In the case of forming a metal oxide thin film having a thickness of 50 to 300 [nm], 10000 to 30000 [nm · m / min] is a film forming condition suitable for the present invention at this dynamic rate.

  According to the present invention as described above, a homogeneous metal oxide thin film can be formed on both surfaces of a sheet such as an electrical insulating sheet. For example, strength and dimensional stability that can be used for a base film for a magnetic tape. Can be obtained at high speed.

  In addition, the sheet | seat with a metal compound thin film obtained continuously as mentioned above is wound up by a roll body. Specifically, for example, a film with an aluminum oxide thin film in which an aluminum oxide thin film having a thickness of 50 [nm] or more is formed on at least one surface of a plastic film having a thickness of 10 [μm] or less and a film width of 1000 [mm]. Becomes a film roll body by being wound around a core having an outer diameter of 80 to 200 [mm]. At this time, in order to prevent generation of wrinkles in the film roll body, the difference between the maximum and minimum values in the sheet width direction of the diameter of the film roll body per 10000 [m] of winding length is preferably within 100 [μm]. However, in the present invention, even if the thickness of the thin film is 50 [nm] or more, the thin film can be formed with a substantially constant film thickness in the sheet width direction. It can have a certain range of diameters in the direction, and wrinkles can be prevented. In addition, even if the difference between the maximum and minimum values in the sheet width direction of the diameter of the film roll body exceeds 100 [μm], the range in which the difference from the maximum diameter of the roll body is larger than 100 [μm] If it is outside the position of 100 [mm] from the end in the width direction of the body, wrinkles that occur in the circumferential direction of the roll body and curving of the transport sheet that causes coating unevenness in subsequent processes are less likely to occur. That is, if the range in which the difference from the roll body maximum diameter per winding length of 10000 [m] in the film width direction is within 100 [μm] continuously exists for W−100 [mm] or more, the film Wrinkles can be prevented from occurring in the circumferential direction of the roll body.

  The measurement method used in this example is shown below.

(1) The thickness of the metal oxide thin film and the cross-sectional structure of the thin film The cross-sectional observation of the metal oxide thin film is performed every 100 mm under the following conditions, starting from the position of 50 mm from the sheet width direction end of 1100 [mm] in width. The average value of the thin film thickness [nm] of 9 points in total obtained for each central region excluding the measurement points at both ends was calculated, and the thin film thickness [nm] at the measurement points at both ends (the smaller value side) Compared with.
Measuring apparatus: Transmission electron microscope (TEM) H-7100FA type Hitachi measurement conditions: Acceleration voltage 100 [kV]
Measurement magnification: 200,000 times Sample preparation: Observation surface of ultrathin film section method: TD-ZD cross-section measurement count: 3 points per field and 3 fields were measured.

(2) Surface resistance value Since the measurable device differs depending on the range of surface resistance value, first measure by the method of I), and measure the sample whose surface resistance value is too low to measure by the method of II) did. The average value of the five measurement results was defined as the surface resistance value in the present invention.

I) High resistivity measurement Based on JIS-C2151 (1990), it measures using the following measuring device.
Measuring device: Digital ultrahigh resistance / microammeter R8340 Advantest Co., Ltd. Applied voltage: 100 [V]
Application time: 10 seconds Measurement unit: Ω
Measurement environment: Temperature 23 ° C Humidity 65% RH
Number of measurements: Measure 5 times.

II) Low resistivity measurement It measures using the following measuring apparatus based on JIS-K7194 (1994).
Measuring device: Lorester EP MCP-T360 Mitsubishi Chemical Measuring Environment: Temperature 23 ° C Humidity 65% RH
Number of measurements: Measure 5 times.

(3) Total light transmittance of sheet with thin film A sample was set in a “haze computer HZ-1” apparatus manufactured by Suga Test Instruments Co., Ltd., and the total light transmittance was measured. The measurement was performed 5 times, and the average value was defined as the total light transmittance in the present invention.

(4) Oxygen introduction amount measurement method A pipe for supplying oxygen via the following mass flow controller is connected to the introduction pipe for supplying oxygen into the metal vapor, and the flow rate of the mass flow controller is adjusted, so that The flow rate display value was read when the optical monitor reached the desired transmittance.
Mass flow controller: Advanced Energy Aera @ FC-7710CD
Calibration gas: oxygen maximum flow rate: 40 [l / min].

(5) Method for measuring diameter of sheet roll body with thin film The sheet roll body with a thin film wound up is a measurement method using a three-point contact displacement sensor described in JP-A-2004-286563. The sensor was relatively moved in the axial direction, and the diameter change [μm] of the film roll body in the roll axial direction was measured. From the profile obtained by measurement over the entire width of the roll body, a point that is the maximum value of the diameter change amount was obtained, and a range in which the maximum / minimum difference was maintained within 100 [μm] was calculated from the point in the width direction. .

[Example 1]
On one side of a polyethylene terephthalate film (“Lumirror” manufactured by Toray Industries, Inc.) having a thickness of 5 [μm] and a width of 1100 [mm] as an electrically insulating sheet, the wound-type vacuum deposition shown in FIGS. It vapor-deposited on the vapor deposition conditions shown below using the apparatus.

(Deposition conditions)
・ Evaporation source container: Alumina crucible ・ Evaporation source heating method: Heating with an electron gun ・ Evaporation material: Aluminum ・ Electron gun input power: 60 [kW]
・ Minimum distance between evaporation source and sheet guide surface: 450 [mm]
-Mask opening length in the film transport direction: 400 [mm]
-Mask opening length in the film width direction: 1000 [mm].

(Film transport conditions)
・ Conveying speed: 150 [m / min]
-Film width: 1100 [mm].

(Sheet guide surface conditions)
A cylindrical sheet guide surface was used as shown in FIG. Inside the sheet guide surface, a medium for adjusting the temperature of the surface of the sheet guide surface is circulated, and a medium having a constant temperature is introduced from a refrigerant circulation device outside the apparatus. Each condition is as follows.
-Diameter of cylindrical sheet guide surface: 1000 [mm]
-Temperature of medium flowing inside the sheet guide surface: -20 [° C].

(Oxygen supply means conditions)
As shown in FIG. 2, the introduction pipe having a round cross-sectional shape arranged toward the region between the evaporation source and the sheet guide surface was arranged under the following conditions.
Inner diameter of introduction pipe 15: 4 [mm] (inner cross-sectional area: about 12.6 [mm ² ])
・ Outer diameter of introduction pipe 15: 6 [mm]
-Length of the straight portion of the introduction pipe 15: 30 [mm]
・ Distance from the upper surface of the crucible of the evaporation source to the opening of the introduction tube: 200 [mm]
・ Direction of the introduction pipe 15: Horizontal direction on the metal vapor side ・ Number of introduction pipes in the sheet width direction: 20 ・ Intervals of the introduction pipes in the sheet width direction: Equal intervals of 50 [mm] 950 [mm]).

(Conditions for vapor diffusion prevention wall)
As shown in FIG. 1, a stainless steel vapor diffusion prevention wall was provided between the crucible 7 as an evaporation source and the width direction mask 11a under the following conditions.
-Length of the vapor diffusion prevention wall in the seat running direction: 300 [mm]
・ Height from the crucible 7 to the highest part of the vapor diffusion prevention wall: 400 [mm]
-Height from the crucible 7 to the lowest part of the vapor diffusion prevention wall: 50 [mm]
-Length of the vapor diffusion prevention wall in the linear direction connecting the crucible 7 and the sheet guide surface: 350 [mm]
-Horizontal distance between the innermost side of the vapor diffusion preventing wall and the inner wall at the end of the crucible 7 in the sheet width direction: 200 [mm]
-Horizontal distance between the innermost side of the vapor diffusion prevention wall and the mask opening: 30 [mm].

(Formation of metal oxide thin film)
The undeposited film roll is set on the original roll body 2 shown in FIG. 7, the film is placed along the intermediate roller 4, the sheet guide surface 3, and the intermediate roller 5, and the film end is attached to the winding roll body 6. did. In the apparatus, an alumina crucible 7 having a volume portion of 150 [mm] in the sheet conveying direction and 1500 [mm] in the sheet width direction is arranged so that the longitudinal direction of the crucible 7 is the same as the film width direction, In this, 20 [kg] of aluminum was set as the vapor deposition material 8. Thereafter, the winding chamber 41a and the film forming chamber 41b of the vapor deposition machine were depressurized and evacuated until the vacuum pressure in the film forming chamber 41b reached 5 × 10 ⁻³ [Pa]. Thereafter, the shutter member 51 was closed and the aluminum in the crucible 7 was melted by the electron gun heating method. The electric power input was 75 [kW]. After confirming that all the aluminum material was melted, the electric energy of the electron gun was finely adjusted to about 60 [kW]. The tension of the raw roll body 2 is set to 140 [N], the tension of the take-up roll body 6 is set to 140 [N], and the speed of the sheet guide surface 3 and the intermediate rollers 4 and 5 is set to 150 [m / min]. The conveyance of the film was started at a speed. Thereafter, aluminum was deposited by opening the shutter member 51. In this state, the pressure in the film forming chamber 41b was 2.0 × 10 ⁻² [Pa]. Thereafter, oxygen was introduced at 28 [l / min] from the introduction tube 15 on the unwinding side and the winding side in the sheet conveying direction of the crucible 7. As the oxygen was introduced, the pressure in the film forming chamber 41b became 3.0 × 10 ⁻² [Pa]. In this state, when the film was observed from the monitoring window 53 on the winding side, the film was brownish and transparent. As for the transmittance, the average value of 11 optical monitors 52 arranged in the sheet width direction was 30%. For this optical monitor, an optical fiber type transmission light transmittance meter (light source central wavelength 565 [nm]) was used. In this state, 11,000 m of film was wound and conveyed to form a film with an aluminum oxide film. Thereafter, the shutter member 51 was closed to stop the introduction of oxygen, and the power supply to the electron gun for heating the evaporation source was cut off. And the conveyance speed was lowered to 5 [m / min], and the pressure release of the winding chamber 41a and the film-forming chamber 41b was performed.

The thickness of the aluminum oxide film formed in this way is as follows. As a result of TEM cross-sectional observation, the average film thickness 98 [nm] at the center in the width direction and the film thickness 92 [nm] at the edge are The depression was 6.1 [%] with respect to the average film thickness in the central part. The film formation rate obtained from the above equation (i) from the average film thickness at the center was 613 [nm / second]. The total light transmittance of the deposited film taken out after the film formation was 53%. The surface resistance value was 1.5 × 10 ⁵ [Ω / □]. Moreover, both ends of the film with an aluminum oxide film thus obtained are slit by 20 [mm], and a film with an aluminum oxide film having a width of 1060 [mm] and a length of 10000 [m] is a core having a diameter of 167 [mm]. A rolled roll body was obtained. As a result of measuring the diameter distribution in the width direction of the obtained roll body, a region having a difference from the maximum value of the roll body diameter within 100 [μm] was present in the center part in the width direction over 990 [mm].

  The film thickness distribution measurement result in the sheet width direction of the aluminum oxide film of the deposited film is shown in FIG. 10, and the diameter distribution of the obtained roll body is shown in FIG. And the vapor deposition conditions and evaluation result of this film with a metal oxide thin film are summarized in Table 1.

[Example 2]
On the single side of a polyethylene terephthalate film ("Lumirror" manufactured by Toray Industries, Inc.) in the same manner as in Example 1 except that the following points were changed using the take-up vacuum deposition apparatus shown in FIGS. A metal oxide thin film was formed.

(Deposition conditions)
・ Evaporation source container: Alumina crucible ・ Evaporation source heating method: Heating with an electron gun ・ Evaporation material: Aluminum ・ Electron gun input power: 60 [kW]
・ Minimum distance between evaporation source and sheet guide surface: 450 [mm]
-Mask opening length in the film transport direction: 400 [mm]
-Mask opening length in the film width direction: 1000 [mm].

(Conditions for vapor diffusion prevention wall)
As shown in FIG. 5, a stainless steel vapor diffusion prevention wall was provided between the crucible 7 as an evaporation source and the width direction mask 11a under the following conditions.
-Length of the vapor diffusion prevention wall in the seat running direction: 300 [mm]
・ Height from the crucible 7 to the highest part of the vapor diffusion prevention wall: 400 [mm]
-Height from the crucible 7 to the lowest part of the vapor diffusion prevention wall: 50 [mm]
-Length of the vapor diffusion prevention wall in the linear direction connecting the crucible 7 and the sheet guide surface: 350 [mm]
-Horizontal distance between the innermost side of the vapor diffusion prevention wall and the inner wall at the end of the crucible 7 in the sheet width direction: 150 [mm]
-Horizontal distance between the innermost side of the vapor diffusion prevention wall and the mask opening: 80 [mm].

(Conditions of gas nozzle for preventing vapor diffusion)
As shown in FIGS. 5 and 6, an introduction pipe having a round cross section is provided as a vapor diffusion preventing gas nozzle 21 between the crucible 7 as an evaporation source and the width direction mask 11 a and inside the vapor diffusion preventing wall 20. Arranged under the following conditions. The vapor diffusion preventing gas nozzles 21 were arranged on both sides in the sheet width direction.
Inner diameter of gas nozzle 21 for preventing vapor diffusion: 4 [mm] (inner cross-sectional area: about 12.6 [mm ² ])
-Outer diameter of gas diffusion preventing gas nozzle 21: 6 [mm]
The direction of the opening of the gas nozzle 21 for preventing vapor diffusion: The direction inside the sheet width direction at an angle of 45 ° from the vertical direction. The number of openings of the gas nozzle 21 for preventing vapor diffusion: 6
-Arrangement of the opening of the gas nozzle 21 for preventing vapor diffusion: The nozzle unit provided with an opening so that the height from the crucible is at a position of 100, 200, 300 [mm], and the center of the crucible is symmetrical in the sheet conveying direction Are arranged with an interval of 100 [mm].
Introducing gas: oxygen.

(Formation of metal oxide thin film)
An undeposited film roll is set on the original roll body 2 in FIG. 4, the film is placed along the intermediate roller 4, the sheet guide surface 3, and the intermediate roller 5, and the film end is attached to the winding roll body 6. . In the apparatus, an alumina crucible 7 having a volume of 150 [mm] in the sheet conveying direction and 1500 [mm] in the sheet width direction is arranged so that the longitudinal direction of the crucible is the same as the film width direction. 20 [kg] of aluminum was set as the vapor deposition material 8. Thereafter, the winding chamber 41a and the film forming chamber 41b of the vapor deposition machine were depressurized and evacuated until the vacuum pressure in the film forming chamber 41b reached 5 × 10 ⁻³ [Pa]. Thereafter, the aluminum in the crucible 7 was melted by the electron gun heating method with the shutter member 51 closed. The electric power input was 75 [kW]. After confirming that all the aluminum material was melted, the electric energy of the electron gun was finely adjusted to about 60 [kW]. The tension of the raw roll body 2 is set to 140 [N], the tension of the take-up roll body 6 is set to 140 [N], and the speed of the sheet guide surface 3 and the intermediate rollers 4 and 5 is set to 150 [m / min]. The conveyance of the film was started at a speed. Thereafter, aluminum was deposited by opening the shutter member 51. In this state, the pressure of the vacuum gauge 10 was 2.0 × 10 ⁻² [Pa]. Thereafter, oxygen was introduced at 26 [l / min] from the upstream and downstream inlet pipes 15 in the sheet conveying direction of the crucible. The amount of oxygen introduced into the vapor diffusion preventing gas nozzle 21 was 3 [l / min]. As the oxygen was introduced, the pressure in the film forming chamber 41b became 3.5 × 10 ⁻² [Pa]. In this state, when the film was observed from the monitoring window 53 on the winding side, the film was brownish and transparent. As for the transmittance, the average value of 11 optical monitors 52 arranged in the sheet width direction was 30%. In this state, 11000 [m] of film was wound and conveyed to form a film with an aluminum oxide film. Thereafter, the shutter member 51 was closed to stop the introduction of oxygen, and the power supply to the electron gun for heating the evaporation source was cut off. And the conveyance speed was lowered to 5 [m / min], and the pressure release of the winding chamber 41a and the film-forming chamber 41b was performed.

The thickness of the aluminum oxide film formed in this way is as follows. As a result of TEM cross-sectional observation, the average film thickness 99 [nm] at the center in the width direction and the film thickness 96 [nm] at the end are The drop was 3.0 [%]. Further, the film formation rate obtained from the equation (i) from the average film thickness at the center was 619 [nm / sec]. The total light transmittance of the deposited film taken out after the film formation was 55%. The surface resistance value was 2.7 × 10 ⁵ [Ω / □]. Moreover, both ends of the film with an aluminum oxide film thus obtained are slit by 20 [mm], and a film with an aluminum oxide film having a width of 1060 [mm] and a length of 10000 [m] is a core having a diameter of 167 [mm]. A rolled roll body was obtained. As a result of measuring the diameter distribution in the width direction of the obtained roll body, a region in which the difference from the maximum value of the roll body diameter was within 100 [μm] was present in the center part in the width direction over 1010 [mm].

  The film thickness distribution measurement result in the sheet width direction of the aluminum oxide film of the deposited film is shown in FIG. 11, and the diameter distribution of the obtained roll body is shown in FIG. And the vapor deposition conditions and evaluation result of this film with a metal oxide thin film are summarized in Table 1.

[Comparative Example 1]
Winding shown in FIGS. 8 and 9 without vapor diffusion preventing means on one side of a polyethylene terephthalate film (“Lumirror” manufactured by Toray Industries, Inc.) having a thickness of 5 [μm] and a width of 1100 [mm] as an electrical insulating sheet It vapor-deposited on the vapor deposition conditions shown below using the type | formula vacuum deposition apparatus.

(Deposition conditions)
・ Evaporation source container: Alumina crucible ・ Evaporation source heating method: Heating with an electron gun ・ Evaporation material: Aluminum ・ Electron gun input power: 60 [kW]
・ Minimum distance between evaporation source and sheet guide surface: 450 [mm]
-Mask opening length in the film transport direction: 400 [mm]
-Mask opening length in the film width direction: 1000 [mm].

(Film transport conditions)
・ Conveying speed: 150 [m / min]
-Film width: 1100 [mm].

(Sheet guide surface conditions)
A cylindrical sheet guide surface 3 was used as shown in FIG. Inside the sheet guide surface 3, a medium for adjusting the temperature of the surface of the sheet guide surface is circulated, and a medium having a constant temperature is introduced from a refrigerant circulation device outside the apparatus. Each condition is as follows.
-Diameter of cylindrical sheet guide surface: 1000 [mm]
-Temperature of medium flowing inside the sheet guide surface: -20 [° C].

(Oxygen supply means conditions)
As shown in FIG. 8, the introduction pipe having a round cross section disposed toward the region between the evaporation source and the sheet guide surface was disposed under the following conditions.
Inner diameter of introduction pipe 15: 4 [mm] (inner cross-sectional area: about 12.6 [mm ² ])
・ Outer diameter of introduction pipe 15: 6 [mm]
-Length of the straight portion of the introduction pipe 15: 30 [mm]
・ Distance from the upper surface of the crucible of the evaporation source to the opening of the introduction tube: 200 [mm]
・ Direction of the introduction pipe 15: Horizontal direction on the metal vapor side ・ Number of introduction pipes in the sheet width direction: 20 ・ Intervals of the introduction pipes in the sheet width direction: Equal intervals of 50 [mm] 950 [mm]).

(Formation of metal oxide thin film)
An undeposited film roll is set on the original fabric roll body 2 shown in FIG. did. In the apparatus, an alumina crucible 7 having a volume of 150 [mm] in the sheet conveying direction and 1500 [mm] in the sheet width direction is arranged so that the longitudinal direction of the crucible is the same as the film width direction. 20 [kg] of aluminum was set as the vapor deposition material 8. Thereafter, the winding chamber 41a and the film forming chamber 41b of the vapor deposition machine were depressurized and evacuated until the vacuum pressure in the film forming chamber 41b reached 5 × 10 ⁻³ [Pa]. Thereafter, the aluminum 8 in the crucible 7 was melted by the electron gun heating method with the shutter member 51 closed. The electric power input was 75 [kW]. After confirming that all the aluminum material was melted, the electric energy of the electron gun was finely adjusted to about 60 [kW]. The tension of the raw roll body 2 is set to 140 [N], the tension of the take-up roll body 6 is set to 140 [N], and the speed of the sheet guide surface 3 and the intermediate rollers 4 and 5 is set to 150 [m / min]. The conveyance of the film was started at a speed. Thereafter, aluminum was deposited by opening the shutter member 51. In this state, the pressure in the film forming chamber 41b was 2.0 × 10 ⁻² [Pa]. Thereafter, oxygen was introduced at 32 [l / min] from the pinhole type nozzles 20 on the upstream side and the downstream side in the sheet conveying direction of the crucible 7. The pressure in the film forming chamber 41b was 3.2 × 10 ⁻² [Pa] according to the introduction of oxygen. In this state, when the film was observed from the monitoring window 53 on the winding side, the film was brownish and transparent. As for the transmittance, an average value of 11 optical monitors 52 arranged in the sheet width direction was 30%. In this state, 11000 [m] of film was wound and conveyed to form a film with an aluminum oxide film. Thereafter, the shutter member 51 was closed to stop the introduction of oxygen, and the power supply to the electron gun for heating the evaporation source was cut off. And the conveyance speed was lowered to 5 [m / min], and the pressure release of the winding chamber 41a and the film-forming chamber 41b was performed.

The thickness of the aluminum oxide film formed in this way is as follows. As a result of TEM cross-sectional observation, the average film thickness 98 [nm] at the center in the width direction and the film thickness 82 [nm] at the edge are The depression was 16.3 [%] with respect to the average film thickness in the central portion. Moreover, the film formation rate calculated | required from (i) Formula from the average film thickness of the center part was 613 [nm / sec]. The total light transmittance of the deposited film taken out after the film formation was 61%. The surface resistance value was 4.2 × 10 ⁸ [Ω / □]. Moreover, both ends of the film with an aluminum oxide film thus obtained are slit by 20 [mm], and a film with an aluminum oxide film having a width of 1060 [mm] and a length of 10000 [m] is a core having a diameter of 167 [mm]. A rolled roll body was obtained. As a result of measuring the diameter distribution in the width direction of the obtained roll body, a region having a difference from the maximum value of the roll body diameter within 100 [μm] was present in the center part in the width direction over 860 [mm].

  FIG. 12 shows the film thickness distribution measurement result in the sheet width direction of the aluminum oxide film of the vapor-deposited film, and FIG. 19 shows the diameter distribution of the obtained roll body. And the vapor deposition conditions and evaluation result of this film with a metal oxide thin film are summarized in Table 1.

  The present invention is very suitable for vacuum vapor deposition for electrically insulating plastic films, but can also be applied to vacuum vapor deposition of webs such as paper and metal foil, and its application range is limited to these. is not.

DESCRIPTION OF SYMBOLS 1 Sheet | seat 2 Original fabric roll body 3 Sheet | seat guide surface 4 Intermediate | middle roller (unwinding side)
5 Intermediate roller (winding side)
6 Winding roll body 7 Crucible (evaporation source)
DESCRIPTION OF SYMBOLS 8 Vapor deposition material 10 Vapor 11a Width direction mask 11b Traveling direction mask 12 Opening part 13 Thin film 15 Introduction pipe 16 Introduction pipe opening part 18 Branch part 19 Oxygen supply piping 20 Vapor diffusion prevention wall 21 Vapor diffusion prevention gas nozzle 22 Vapor diffusion prevention wall Interval 24 Partition 25 Sheet conveying direction 26 Sheet deposition region 29 Gas introduction path 30 Deposition start point 31 Deposition end point 32 Separation point 33 Winding point 41 Decompression chamber 41a Winding chamber 41b Deposition chamber 42 Vacuum pump 42a Winding Vacuum pump for intake chamber 42b Vacuum pump for film formation chamber 43 Valve 44 Gas cylinder 45 Pressure reducing valve 46 Gas flow controller 51 Shutter member 52 Optical monitor 53 Viewing window 100 Position where opening exists

Claims (8)

A sheet guide surface configured to convey the sheet while being in contact with the sheet; a conveying unit configured to convey the sheet along with the movement of the sheet guide surface; and metal vapor is scattered toward the sheet on the sheet guide surface. An evaporation source for reacting, a reaction gas introducing means for introducing a gas for reacting with the metal vapor, and a mask for limiting a region where the metal vapor reaches the sheet, and continuously supplying the metal to the conveyed sheet An apparatus for manufacturing a sheet with a metal compound thin film that forms a compound thin film, the gas introduced by the reaction gas introducing means and the metal flying from the evaporation source in a linear direction connecting the evaporation source and the sheet guide surface a position where the steam mixed, Ri Na provided diffusion preventing means for preventing the metal vapor diffuses to the outside of the seat width direction,
The diffusion preventing means is a pair of wall-shaped structures, and the wall-shaped structures project inward from the sheet width direction end of the evaporation source;
When the shortest distance between the sheet guide surface and the evaporation source is D [m], the length of the wall-like structure is 0.5 D [m] with respect to the linear direction connecting the evaporation source and the sheet guide surface. That's it,
Equipment for manufacturing sheet with metal compound thin film. 2. The metal compound thin film according to claim 1 , wherein the length of the opening of the mask in the sheet width direction is A [m] and the shortest distance between the pair of wall structures is C [m]. Equipment for manufacturing attached sheets.
A <C ≦ 1.2A 3. The metal compound thin film attachment according to claim 1, wherein the reaction gas introduction means has a gas introduction port at a position where the wall-like structure exists in a linear direction connecting the evaporation source and the sheet guide surface. Sheet manufacturing equipment. The metal compound thin film according to any one of claims 1 to 3, wherein the diffusion preventing means is a gas supply means and a wall-like structure, and the wall-like structure is provided outside the gas supply means in the sheet width direction. Forming equipment. A metal compound thin film is continuously formed on the sheet by using the apparatus according to any one of claims 1 to 4 and simultaneously introducing a metal vapor from the evaporation source toward the sheet and simultaneously introducing a gas into the metal vapor. method for producing a metal compound thin film with a sheet that form a. 6. The metal compound according to claim 5 , wherein the metal is aluminum, the gas is oxygen, the metal compound thin film is an aluminum oxide film, and a deposition rate of the aluminum oxide film is 400 [nm / sec] or more. Manufacturing method of sheet with thin film. The manufacturing method of the sheet | seat with a metal compound thin film of Claim 6 whose film thickness of the said metal compound thin film exists in the range of 50-300 [nm]. In any of the methods of claims 5-7, double-metal compound manufacturing method of a thin film with a sheet that form a metal oxide thin film on both sides of the sheet.

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