JP4162953B2 - Solvent coating apparatus and solvent coating method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method for applying a solvent to a flexible support, and more particularly to an application method and apparatus used in manufacturing a magnetic recording medium.
[0002]
[Prior art]
There are gravure coating, rod coating, extrusion coating, etc. as a method of applying paint to the flexible support, but if the paint goes around to the back side of the flexible support during application, the guide rolls may become dirty. When the flexible support is wound in a roll shape, the ends of the flexible support stick to each other, causing a problem that the sticking portion is torn when being extended again. It is common to provide a part where the paint is not applied to the body end. (Here, the end indicates an angle formed by the application surface and the side surface of the flexible support, and the end indicates the end of the flexible support on the application surface and the vicinity thereof.)
[0003]
However, in methods such as extrusion coating and rod coating that apply while pressing the applicator against the flexible support, the flexible support and the applicator are not in direct contact with the part where the paint is applied. Although there is no paint, the flexible support is scraped because the flexible support and the coating device are in direct contact with each other, and the waste generated thereby wraps around the paint discharge portion of the coating device. There is a problem in that streaks are generated on the coated surface, and the residue is caught on the coated surface, which causes an error during signal recording / reproduction.
[0004]
In order to solve this problem, it has been proposed to apply a solvent in advance to a portion of the flexible support to which the paint is not applied immediately before applying the paint to the flexible support (see Patent Document 1). ). In addition, in a coating method in which a solvent is applied in advance to a portion where the flexible support is not applied immediately before the coating is applied to the flexible support, the solvent applied immediately before and the solvent in the coating are dissolved. It has been proposed that the difference in SP value, which is a property parameter, be 1.2 or more at 25 ° C. (see Patent Document 2).
[0005]
[Patent Document 1]
JP-A-61-257268
[Patent Document 2]
Japanese Patent Laid-Open No. 2-107381
[0006]
[Problems to be solved by the invention]
By applying a solvent in advance to the part of the flexible support that is not coated with paint, the flexible support and the coating device are not in direct contact with each other, and the flexible support is provided by the lubricating effect of the solvent. You can prevent the body from shaving. However, if the solvent overlaps with the part to which the paint is applied, the paint application surface will be disturbed, and this disturbed part will cause an error during signal recording or reproduction, and if this solvent goes around to the back of the flexible support. Then, the coating material is guided to the solvent, and the coating material wraps around to the back side. The coating roller is soiled by the coating material, and the flexible supports adhere to each other when wound in a roll shape. In addition, when a lubricant or the like is added to the solvent or when an adhesive impurity is mixed, sticking occurs even if the solvent only wraps around the back side of the flexible support. For this reason, it is preferable that the width | variety which apply | coats a solvent does not overlap the part to which a coating material is applied, and the end of a flexible support body, and is a wide range in order to prevent abrasion.
[0007]
However, the width of the portion of the flexible support where the coating is not applied varies depending on the flexible support, the coating device, the coating, the coating conditions, and the like. The method was difficult or cumbersome to operate.
[0008]
An object of the present invention is to provide a coating apparatus and method that can solve the above-mentioned problems in solvent coating and can easily adjust the solvent coating width.
[0009]
[Means for Solving the Problems]
  As a result of studying the solvent coating apparatus and method, the present inventor has been able to achieve the above object by the invention described in the claims of the present application.
(1) In an apparatus for applying a solvent to the surface of the flexible support before applying a paint to one surface of the traveling flexible belt-shaped support,
  The solvent supply portion that contacts the surface of the flexible support and supplies the solvent is made of a porous material, the tip can be rotated in a shape other than a circle, and the coating width of the solvent can be changed. And
  The coating width of the solvent is determined so that the coating film of the applied solvent does not overlap with either the portion to which the paint is applied or both side edges of the flexible support. Solvent coating device.
(2) The solvent coating apparatus according to (1), wherein the solvent supply portion is movable in the width direction of the flexible support and can be separated from and contacted with the flexible support.
(3) In a method of applying a solvent to the surface of the flexible support before applying a paint to one surface of the traveling flexible belt-shaped support,
  The solvent supply portion that contacts the surface of the flexible support and supplies the solvent is made of a porous material, and the solvent application width is changed by rotating the tip of the shape other than the circle of the solvent supply portion. ,
  A method of applying a solvent, wherein the solvent is applied so that a coating film of the applied solvent does not overlap any of a portion to which the paint is applied and both ends of the flexible support.
(4) The solvent coating method according to (3), wherein the paint contains a magnetic material and / or a nonmagnetic material in the production of a magnetic recording medium.
(5) The solvent coating method according to (3), wherein the coating material is a backcoat forming material in the production of a magnetic recording medium.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a state in which a solvent is applied to the end of the flexible support. When the flexible support 4 is conveyed in the directions of arrows 6 and 7 through the guide roll 5, the tip 1 of the solvent supply portion 2 disposed at the end of the flexible support is the end of the flexible support. The solvent coating 3 is applied by supplying the solvent to the flexible support. The width of the contact portion of the tip 1 is the solvent application width (the width of the solvent coating 3). Rotating the tip 1 changes the width of the contact portion, thereby making it possible to easily change the solvent application width.
[0011]
If the tip of the solvent supply portion has a shape other than a circle, the coating width of the solvent applied when the tip is rotated changes. For example, when the tip 1 is rectangular as shown in FIG. 2A, when the flexible support is transported from below the tip 1, the solvent application width is as shown by the arrow. The long side of the rectangle. As shown in FIG. 2 (b), when the tip is rotated by 45 ° about an axis perpendicular to the application surface of the flexible support, the solvent application width is the length between the long side and the short side of the rectangle. Then, when this is further rotated by 45 °, as shown in FIG. 2 (c), the solvent application width becomes the length of the short side of the rectangle. Thus, when the tip is rectangular, the solvent application width can be freely changed between the long side and the short side of the rectangle by rotating the tip. When the shape of the tip is a circle, even if it is rotated, the width of the contact portion is always the diameter of the circle, and the application width of the solvent does not change, so it is meaningless.
[0012]
As the shape of the tip, for example, shapes as shown in FIGS. 3A, 3B, 3C, 3D, 3E, and 3F are conceivable. There is no particular limitation. In order to make the film thickness of the solvent coating film uniform in the width direction of the flexible support, it is preferable that the length of the flexible support in the longitudinal direction is uniform in the width direction. The rectangles with greatly different lengths of the short side and the long side can change the coating width of the solvent the most when the tip is rotated, and the thickness of the solvent coating is likely to be uniform in the width direction. Since shape processing is easy, it is preferable. In the case of a circle, there is no effect because the coating width does not change even if it is rotated.
[0013]
The tip can be easily rotated, for example, by manually rotating a solvent supply pipe (hereinafter referred to as a pipe) joined to the solvent supply portion, and this method is preferable because no rotation mechanism is required. By making the length direction of the pipe to be rotated perpendicular to the coating surface and making the tip surface parallel to the flexible support, the contact surface is always equal to the flexible support when the tip is rotated. This can make the thickness of the solvent coating uniform. The tip rotation method is not particularly limited as long as the tip rotates and the application width of the solvent becomes variable.
[0014]
Since the solvent supply portion is made of a porous material, the hole can be impregnated with the solvent supplied from the pipe, and the solvent can be applied to the flexible support that comes into contact with the oozing solvent. The porous substance can be applied with the contained solvent by contacting the flexible support, and the tip contacting the flexible support can be formed in any shape. There is no particular limitation. In addition, the porous material should be made of a softer material than the flexible support in order to prevent the flexible support from being torn by accidentally being strongly pressed in contact with the flexible support. Is preferred. As the porous material, for example, felt (condensed fiber entangled by applying moisture, heat and pressure) or the like can be used. A felt is preferable because it can be easily cut into an arbitrary shape with a cutter or the like and is softer than a flexible support.
[0015]
The shape of the solvent supply part is not particularly limited, but instead of making the whole pointed from the point of strength, for example, when creating a solvent supply part with a rectangular shape at the tip, first the porous material has a square cross section It is preferable to form a prismatic shape, process a cross section of one prismatic shape, and form a rectangular shape only at the tip.
[0016]
The degree of contact of the tip is not particularly limited, but it is preferable that the tip is slightly pushed from the state in which the tip is in contact with the flexible support in order to stably apply the shaking of the flexible support. . If the push-in is too much, the push-in part is the end of the flexible support, so the end of the flexible support will easily be rounded and the tip will be able to contact the flexible support evenly. Disappear.
[0017]
As described above, the embodiment in which the tip of the solvent supply portion is rotated about the axis perpendicular to the application surface of the flexible support has been mainly described. However, as another embodiment, the fan shape and the thickness of the side surface 42 of the arc change in FIG. The solvent supply part 41 formed in this way is shown. The side surface 42 of the arc, which is the tip of the solvent supply portion, is brought into contact with the flexible support to supply the solvent to the flexible support, and the solvent supply portion is rotated in the direction of the arrow 47 by the rotating shaft 46 to obtain the arc thickness. By shifting the portion, the solvent application width can be changed from the arrow 43 to the arrow 44.
[0018]
FIG. 5 shows how the solvent is applied to the flexible support at the solvent supply portion 41. The flexible support 4 continues from the back side of the drawing to the front side of the drawing, and the side surface 42 of the arc of the solvent supply portion is in contact with the end of the flexible support 4. By rotating the pipe 50 joined to the solvent supply portion 41 in the direction of arrow 49, the side surface 42 of the solvent supply portion contacting the flexible support 4 can be shifted to change the solvent application width. The shape of the solvent supply portion and the axis of rotation thereof are not particularly limited as long as the solvent supply portion can be rotated to change the coating width.
[0019]
The method for joining the solvent supply part and the pipe is not particularly limited. For example, the end of the solvent supply part to be joined to the pipe is made slightly larger than the inner diameter of the pipe, and the end can be joined by pushing the end into the pipe. . In this bonding, the porous material expands by being impregnated with the solvent, and is more strongly fixed to the pipe. In addition, the piping that is directly joined to the solvent supply portion is made of a soft material such as a silicone tube, so that when the large protrusions or steps contact the solvent supply portion, the solvent supply portion is deformed. Before the piping is deformed, the impact received by the solvent supply portion can be reduced. (As a large protrusion or step, for example, when a flexible support wound in the form of a roll is applied continuously by two rolls, the flexibility of the roll to be applied next when the first roll is fed out and the remaining amount becomes small. The flexible support can be drawn out continuously by instantaneously joining the end of the flexible support to the flexible support being drawn out of the first roll with an adhesive or the like. Is a large protrusion due to the overlap between the flexible supports and the adhesive).
[0020]
In order to adjust the position so that the solvent coating is applied to the center of the part where the paint is not applied, because the position of the end of the flexible support differs depending on the width of the flexible support and its transport position. The solvent supply portion is preferably movable in the width direction of the flexible support.
[0021]
In addition, due to a large shift in the transport position that occurs at the start of transport of the flexible support, etc., the solvent supply part comes off the application surface of the flexible support, and the solvent supply part is pushed into the flexible support. The solvent supply part is flexible in order to prevent the flexible support from being broken by contact with the side surface of the flexible support that protrudes to the original travel position. It is preferable that it can be separated from the support. In particular, when the flexible support is made of a material such as polyethylene naphthalate (PEN) that breaks due to slight scratches on the side surface, the tip of the paint supply unit does not contact the side surface of the flexible support. It is preferable that the solvent supply part is first held at a position away from the flexible support, and the application is started by bringing the solvent supply part into contact after the conveyance of the flexible support is stabilized.
[0022]
As these methods, for example, on an air cylinder or an air slide unit (both devices in which the main body and the head are joined by inserting a rod and the main body or the head can move along the rod by compressed air) By fixing the solvent supply portion, the solvent supply portion can be moved. The method and apparatus are not particularly limited as long as the solvent supply portion can be moved.
[0023]
The solvent supply part is connected to a solvent tank through a pipe. The supply of the solvent to the solvent supply part can be performed by the weight of the solvent in the solvent tank by installing the solvent tank at a position higher than the solvent supply part, and a known method such as a pump. Can be used, and is not particularly limited.
[0024]
The supply amount of the solvent can be adjusted by a valve provided in the middle of the pipe, and the coating thickness can be adjusted by the supply amount. The amount of solvent supplied depends on the conveyance speed of the flexible support and the contact state of the coating material application device, and the applied solvent does not completely evaporate. The coating thickness is adjusted so as to reach a position where the flexible support can be prevented from being scraped off.
[0025]
The application of the solvent is performed before applying the paint so that the applied solvent does not evaporate while reaching the position where the paint is applied, and prevents the flexible support from being scraped without the solvent evaporating. If possible, the distance between the solvent supply part and the coating device is not particularly limited. When the solvent coating film and the guide roll come into direct contact, the coating width of the solvent changes, or the friction between the guide roll and the flexible support changes, which changes the transport position of the flexible support. It is preferable that there is no guide roll in direct contact with the solvent coating film before reaching the coating device.
[0026]
  Since the solvent coating is crushed and slightly spread when it contacts the coating device, the expanded solvent coating should not overlap the area where the coating is applied and the edge of the flexible support. Determine the coating widthThe
[0027]
A known solvent such as methyl ethyl ketone or a mixed solvent thereof can be used as the solvent, and is not particularly limited. It is preferable that the solvent is completely dried in a drying furnace installed after the coating device, in order to prevent problems such as the applied solvent comes into contact with the traveling guide and the friction, and the traveling position changes due to friction. Those having a boiling point lower than the temperature of the drying furnace to be used and easily evaporate completely in the drying furnace are preferred. It is also possible to add a known lubricant such as silicone in order to reduce the friction between the flexible support and the coating device.
[0028]
  As the flexible support and the paint, conventional ones can be used. In the case where the coating material is a magnetic material, a non-magnetic material, or a backcoat forming material for producing a magnetic recording medium, these coating materials mainly comprise a pigment, a binder resin, and a solvent. For this reason, when the coating material wraps around the back surface of the flexible support due to the binder resin or its cross-linking agent, sticking of the flexible supports strongly occurs. In addition, even a very small amount of defects due to debris resulting from scraping of the flexible support causes an error during signal recording or reproduction. For this reason, when applying magnetic materials, non-magnetic materials, and backcoat forming materialsIs meltedIf the coating width of the agent overlaps the part where the paint is applied or the end of the flexible supportDo not. AndTo prevent scrapingThe solvent application widthA wide range is preferable.
[0029]
Further, the application of the solvent at the end of the flexible support according to the present invention can be performed on the flexible support even when the magnetic material, the non-magnetic material, and the backcoat forming material are applied to the flexible support. A nonmagnetic material may be applied, and then the magnetic material may be applied onto the formed nonmagnetic layer, or the magnetic material and the nonmagnetic material may be applied simultaneously or sequentially.
[0030]
A known coating device can be used. In particular, the present invention is preferably applied to a case where a paint is applied while pressing an application device against a flexible support, such as extrusion coating or rod coating.
[0031]
【Example】
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 6 shows the solvent supply unit 10 of the solvent coating apparatus used for carrying out the present invention. The solvent supply portion 2 is formed of felt so that the tip 1 is rectangular (1.5 mm × 6 mm), and the rear portion is inserted into a pipe 9 made of a silicone resin tube having an inner diameter of 5.5 mm. The pipe 9 is joined to a fluorine resin tube pipe 11 having an outer diameter of 6.0 mm, and the pipe 11 is joined to a joint 12. By using a one-touch joint having a tube grip structure for the joint 12, the pipe 11 is rotatably joined, and the tip 1 can be rotated by manually rotating the pipe 11. The pipe 11 is fixed on the head 14 of the air cylinder (SMS CXS) by the gripping part 13, and the air cylinder body 16 is attached to the body 18 of the air slide unit (SMC CX2) by the bolt 37. Since the head 14 is fixed, the head 14 can move in the direction of the arrow 17 along the rod 15, so that the tip 1 can be separated from the flexible support 4.
[0032]
Further, since the head 20 of the air slide unit is fixed, the main body 18 can move along the rod 19 in the direction of the arrow 21, and the tip 1 can move in the width direction of the flexible support 4. Become. Further, the position of the main body 18 is determined by the tip of the position adjusting screw 22 coming into contact with the side surface of the main body 18 and being pressed with compressed air from the opposite side, and the position adjusting screw 22 is moved in the direction of arrow 23. By rotating and changing the length of the position adjusting screw 22 inserted into the head 20, the position of the tip 1 of the solvent supply portion 2 can be finely adjusted.
[0033]
FIG. 7 shows a part of the solvent application device and the coating material application device 29. The solvent supply unit 10 is installed on the gantry 24, and the solvent coating 3 is applied when the tip 1 of the solvent supply part 2 comes into contact with the flexible support 4. The solvent supply unit 10 is coupled to a solvent tank 25 through a pipe 2 8. An open / close valve 26 and a flow rate adjusting valve 27 are attached to the pipe 28, thereby adjusting the amount of solvent supplied to the solvent supply portion 2. The flexible support 4 is conveyed in the directions of arrows 35 and 36 through the guide rolls 32, 33 and 34, and comes into contact with a coating material application device (extrusion type nozzle) 29 between the guide rolls 33 and 34. Due to the relationship between the guide roll and the like, the solvent supply part 2 was installed at a position where the flexible length between the solvent supply unit 10 and the coating material application device 29 was 1 m. The solvent used was methyl ethyl ketone.
[0034]
(Non-magnetic material)
Acicular hematite (α-FeOOH) 80.0 parts by mass
(Long axis length: 100 nm, crystallite diameter 12 nm)
Carbon black ... 20.0 parts by mass
(Mitsubishi Chemical Corporation, # 950B, particle size: 17 nm)
Binder resin 1 (vinyl chloride resin) (solid content) 11.0 parts by mass
(Toyobo Co., Ltd., TB-0246, solid content = 30% by mass))
Binder resin 2 (polyurethane resin) (solid content) 9.0 parts by mass
(Toyobo Co., Ltd., TB-0216, solid content = 35% by mass)
Dispersant: 1.2 parts by mass
(Toho Chemical Industries, RE610, phenylphosphonic acid)
Abrasive ... 4.0 parts by mass
(Sumitomo Chemical Co., Ltd., HIT60A, α-alumina)
Fatty acid: 0.5 parts by mass
(NAF180, manufactured by Nippon Oil & Fats Co., Ltd.)
Fatty acid amide 0.5 parts by mass
(Fatty acid amide S manufactured by Kao Corporation)
Fatty acid ester: 1.0 part by mass
(Nikko Chemicals, Nikkor BS)
Solid content concentration = 30.0 mass%
Solvent ratio: methyl ethyl ketone / toluene / cyclohexanone = 2/2/1 (mass ratio)
[0035]
After kneading the above materials (excluding part of the solvent) with a kneader, this is dispersed with a horizontal pin mill filled with 80% zirconia beads with a diameter of 0.8 mm (porosity 50% by volume), and finally the remaining solvent is added. The viscosity was adjusted. Thereafter, the mixture was filtered through a filter having an average pore diameter of 0.5 μm to prepare a nonmagnetic material paint.
[0036]
(Magnetic material)
Ferromagnetic powder: 100.0 parts by mass
(Iron-based acicular magnetic powder (Fe / Co / Al / Y = 100/24/5/8 (atomic ratio),
Hc: 189 kA / m, σs: 135 Am²/ Kg, long axis length: 100 nm)
Binder resin 1 (vinyl chloride resin) ... 14.0 parts by mass
(Manufactured by Nippon Zeon Co., Ltd., MR110, solid content concentration = 100 mass%)
Binder resin 2 (polyurethane resin) ... (solid content) 2.0 parts by mass
(Toyobo Co., Ltd., UR8700, solid content = 35% by mass)
Dispersant ... 3.0 parts by mass
(Toho Chemical Industries, RE610, phenylphosphonic acid)
Abrasive ... 4.0 parts by mass
(Sumitomo Chemical Co., Ltd., HIT82, α-alumina, average particle size: 0.12 μm)
Fatty acid: 1.2 parts by mass
(NAF180, manufactured by Nippon Oil & Fats Co., Ltd.)
Fatty acid ester: 1.0 part by mass
(Nikko Chemicals, Nikkor BS)
Solid content concentration = 16% by mass
Solvent ratio: methyl ethyl ketone / toluene / cyclohexanone = 1/1/3 (mass%)
[0037]
The above materials (excluding a part of the solvent) were kneaded with a kneader, dispersed with a horizontal pin mill, and finally the remaining solvent was added to adjust the viscosity. The magnetic layer coating material thus obtained was mixed with 4 parts by weight of a curing agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L), and then filtered through a filter having an average pore size of 0.5 μm to form a magnetic material coating material. Was made.
[0038]
(Back coat forming material)
Carbon black: 75.0 parts by mass
(Cabot Corporation, BP-800, average particle size 17 nm)
Carbon black: 10.0 parts by mass
(Cabot Corporation, BP-130, average particle size 75 nm)
Calcium carbonate ... 15.0 parts by mass
(Manufactured by Shiroishi Kogyo Co., Ltd., white gloss flower O, average particle size 30 nm)
Polishing agent ... 0.2 parts by mass
(Daimei Chemical Co., Ltd., TM-DR, α-alumina, average particle size 230 nm)
Binder resin 1 (nitrocellulose) (solid content) 65.0 parts by mass
(Asahi Kasei Kogyo Co., Ltd., BTH1 / 2, solid content = 70% by mass)
Binder resin (polyurethane resin) ... (solid content) 35.0 parts by mass
(Toyobo Co., Ltd., UR-8700, solid content = 30% by mass)
Solid content concentration = 11.5 mass%
Solvent ratio: methyl ethyl ketone / toluene / cyclohexanone = 50/40/10 (mass ratio)
[0039]
After kneading the above materials (excluding a part of the solvent) with a kneader, this is dispersed with a horizontal pin mill filled with 80% zirconia beads with a diameter of 0.8 mm (porosity 50 volume%), and finally the remaining solvent is added. The viscosity was adjusted. 4 parts by mass of a curing agent (Nippon Polyurethane Industry Co., Ltd., Coronate L) was added to and mixed with the thus obtained back coat layer coating material, and then filtered through a filter having an average pore size of 0.5 μm. A paint of the forming material was produced.
[0040]
Using the coating material thus obtained, a magnetic recording medium was produced in the following manner.
(Coating process)
(Non-magnetic layer forming process)
A nonmagnetic material and a solvent were applied to one surface of the flexible support 4. A flexible support 4 made of polyamide having a thickness of 4.5 μm wound in a roll is fed out and conveyed at a conveyance speed of 200 m / min. After this traveling position is stabilized, the tip 1 of the solvent supply portion 2 is moved to the solvent. The width of the coating was brought into contact with both ends of the flexible support 4 at an angle at which the rectangular short side was applied, and the coating of the solvent was started. The tip 1 was brought into contact with the tip 1 only slightly from the state where the tip 1 was in contact. At this time, the amount of the solvent dripping from the tip 1 of the solvent supply portion 2 was about 0.05 ml / s in a state where the solvent supply portion 2 was separated from the flexible support 4.
[0041]
Next, the application of the nonmagnetic material was started with a coating device 29 (extrusion type nozzle) so that the thickness after the calendar treatment (surface smoothing treatment) was 1.4 μm. At this time, the width of the end portion of the flexible support 4 where the paint is not applied is about 3 mm at both ends of the flexible support 4, and the tip 1 is rotated by manually rotating the pipe 11, and the solvent. The application width was about 2 mm, and fine adjustment was performed with the position adjusting screw 22 so that the solvent coating film was applied to the center of the portion where the paint was not applied. The flow rate was adjusted so that the applied solvent did not dry before reaching the coating device 29. The coating film formed by applying the paint was dried and then subjected to a calender treatment, and further irradiated with an electron beam at 4.5 Mrad to form a nonmagnetic layer, and then wound into a roll. Application was performed by continuously rolling 10 rolls of 6000 m.
[0042]
(Magnetic layer forming process)
Subsequently, a magnetic material and a solvent were applied to the surface on which the nonmagnetic layer was formed. The flexible support 4 is again unwound from the roll on which the nonmagnetic layer is formed and conveyed at 200 m / min. After the running position is stabilized, the tip 1 of the solvent supply portion 2 is short with a rectangular width of solvent application. The both ends of the flexible support 4 were brought into contact with each other at an angle to be a side, and application of the solvent was started. The tip 1 was brought into contact with the tip 1 only slightly from the state where the tip 1 was in contact. At this time, the amount of the solvent dripping from the tip 1 of the solvent supply portion 2 was about 0.05 ml / s in a state where the solvent supply portion 2 was separated from the flexible support 4.
[0043]
Next, application of the magnetic material was started with an extrusion type nozzle so that the thickness after calendering the magnetic material paint on the nonmagnetic layer was 0.15 μm. At this time, the width of the portion where the paint is not applied at the end of the flexible support 4 is about 4 mm at both ends, and the tip 1 is rotated by manually rotating the pipe 11 so that the solvent application width is about 3 mm. Then, the position adjustment screw 22 was finely adjusted so that the solvent coating film was applied to the center of the portion where the paint was not applied. The flow rate was adjusted so that the applied solvent did not dry before reaching the coating device 29. The coating film formed by applying the paint was subjected to 0.7T magnetic field and oriented and dried, and further calendered to form a magnetic layer, and then wound into a roll. Application was performed by continuously rolling 10 rolls of 6000 m.
[0044]
(Back coat forming process)
Subsequently, a back coat forming material and a solvent were applied to the surface opposite to the surface on which the magnetic layer was formed. The flexible support 4 is again fed out from the roll on which the magnetic layer is formed, and is conveyed at a conveyance speed of 150 m / min. After this traveling position is stabilized, the tip 1 of the solvent supply portion 2 has a rectangular width of solvent application. The both sides of the flexible support 4 were brought into contact with each other at an angle that became a short side of and the application of the solvent was started. The tip 1 was brought into contact with the tip 1 only slightly from the state where the tip 1 was in contact. At this time, the amount of the solvent dripping from the tip 1 of the solvent supply portion 2 was about 0.05 ml / s in a state where the solvent supply portion 2 was separated from the flexible support 4.
[0045]
Next, a back coat forming material was applied and applied to the other surface of the flexible support 4 on which the magnetic layer was formed, using an extrusion type nozzle so that the thickness after calendering was 0.5 μm. At this time, the width of the portion where the paint is not applied at the end of the flexible support 4 is about 6 mm at both ends, and the tip 1 is rotated by manually rotating the pipe 11 so that the solvent application width is about 5 mm. The position adjustment screw 22 was finely adjusted so that the solvent coating film was applied to the center of the portion where the paint was not applied. The flow rate was adjusted so that the applied solvent did not dry before reaching the coating device 29. The coating film formed by applying the paint was dried, further subjected to a calendering process to form a back coat, and then wound up into a roll. Application was performed by continuously rolling 10 rolls of 6000 m.
[0046]
The thus prepared roll of the magnetic recording medium was allowed to stand at 60 ° C. for 48 hours for thermosetting. Thereafter, it is cut into a width of 3.8 mm, and incorporated into a cartridge for DDS-4 (3.8 mm width, helical scanning recording, information exchange magnetic cartridge, digital data storage-4 format), and the magnetic recording medium (DDS- of the embodiment) 4) was produced.
[0047]
The application width of the solvent at the time of applying each paint can be easily changed by rotating the tip 1 of the solvent supply portion 2. The application state of each paint was visually observed, and it was confirmed that the application width of the solvent was applied without overlapping the portion where the paint was applied and the end of the flexible support 4. When the flexible support 4 was unwound from the roll in each step, the flexible support 4 did not break due to sticking.
[0048]
In addition, no coating streaks were generated during coating, and the coating device 29 was visually observed after coating, but no debris generated by scraping the flexible support 4 could be found. Also, the error was measured by running the magnetic recording medium in the DDS-4 drive, and the place where the error occurred was observed with an optical microscope or SEM (scanning electron microscope). Neither the part where the coating surface was disturbed due to the above, nor the residue generated when the flexible support 4 was scraped were found.
[0049]
The preferred embodiments and examples of the solvent coating apparatus of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to these examples. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims, and of course, the technical scope of the present invention is also possible. It is understood that it belongs to.
[0050]
【The invention's effect】
As described above, according to the present invention, before applying the paint to the flexible support, when applying the solvent in advance to the portion where the paint at the end of the flexible support is not applied, it is easy to remove the solvent. By adjusting the coating width, it is possible to simplify the trouble of changing the coating width of the solvent in accordance with the width of the portion where the coating material, which varies depending on the flexible support, the coating device, the coating material, and the coating conditions, is not applied.
[Brief description of the drawings]
FIG. 1 is a perspective view for explaining a method of applying a solvent to an end portion of a flexible support.
FIG. 2 is a partially enlarged view for explaining that the coating width of the solvent changes when the tip of the solvent supply portion rotates.
FIG. 3 is a partially enlarged view for explaining the shape of the tip of the solvent supply portion.
FIG. 4 is a perspective view for explaining a fan-shaped solvent supply portion;
FIG. 5 is a top view for explaining that a solvent is applied to a flexible support at a fan-shaped solvent supply portion;
FIG. 6 is a perspective view for explaining a solvent supply unit of the solvent coating apparatus.
FIG. 7 is a perspective view for explaining a part of a solvent coating device and a coating material coating device.
[Explanation of symbols]
1 Tip
2 Solvent supply part
3 Solvent coating
4 Flexible support
5, 32, 33, 34 Guide roll
6, 7, 17, 21, 23, 35, 36, 43, 44, 47, 49 Arrow
9 Piping made of silicone resin tube
10 Solvent supply section
11 Piping made of fluororesin tube
12 Fitting
13 gripping part
14 Air cylinder head
15, 19 Rod
16 Air cylinder body
18 Air slide unit body
20 Air slide unit head
22 Position adjustment screw
37 volts
24 frame
25 Solvent tank
26 Open / close valve
27 Flow control valve
28, 50 piping
29 Coating device
41 Solvent supply part
42 Sides of the arc
46 Rotating shaft

Claims (5)

In an apparatus for applying a solvent to the surface of the flexible support before applying a paint to one surface of the traveling flexible belt-like support,
The surface and in contact with solvent supply part for supplying a solvent of the flexible support is made of a porous material, and tip Ri rotatable der a shape other than a circle, made to be able to change the coating width of the solvent And
The coating width of the solvent is determined so that the coating film of the applied solvent does not overlap with either the portion to which the paint is applied or both ends of the flexible support. Solvent coating device. The solvent coating apparatus according to claim 1 , wherein the solvent supply portion is movable in the width direction of the flexible support and is detachable from the flexible support. In a method of applying a solvent to the surface of the flexible support before applying a paint to one surface of the traveling flexible belt-shaped support,
The solvent supply portion that contacts the surface of the flexible support and supplies the solvent is made of a porous material, and the solvent application width is changed by rotating the tip of a shape other than a circle of the solvent supply portion. ,
A solvent coating method , wherein the solvent is coated such that the coated film of the coated solvent does not overlap with either the portion to which the paint is applied or both ends of the flexible support . 4. The solvent coating method according to claim 3 , wherein the paint contains a magnetic material and / or a nonmagnetic material in the production of a magnetic recording medium . The solvent coating method according to claim 3 , wherein the paint is a backcoat forming material in magnetic recording medium production .

Images