EP0530752A1 - Coating method - Google Patents
Coating method Download PDFInfo
- Publication number
- EP0530752A1 EP0530752A1 EP92114937A EP92114937A EP0530752A1 EP 0530752 A1 EP0530752 A1 EP 0530752A1 EP 92114937 A EP92114937 A EP 92114937A EP 92114937 A EP92114937 A EP 92114937A EP 0530752 A1 EP0530752 A1 EP 0530752A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- web
- coating
- backup roller
- support
- coating solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/14—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by electrical means
- B05D3/141—Plasma treatment
- B05D3/142—Pretreatment
- B05D3/144—Pretreatment of polymeric substrates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/007—Processes for applying liquids or other fluent materials using an electrostatic field
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/74—Applying photosensitive compositions to the base; Drying processes therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/26—Processes for applying liquids or other fluent materials performed by applying the liquid or other fluent material from an outlet device in contact with, or almost in contact with, the surface
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D2252/00—Sheets
- B05D2252/02—Sheets of indefinite length
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0218—Pretreatment, e.g. heating the substrate
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/76—Photosensitive materials characterised by the base or auxiliary layers
- G03C1/91—Photosensitive materials characterised by the base or auxiliary layers characterised by subbing layers or subbing means
- G03C1/915—Photosensitive materials characterised by the base or auxiliary layers characterised by subbing layers or subbing means using mechanical or physical means therefor, e.g. corona
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
- G03C1/00—Photosensitive materials
- G03C1/74—Applying photosensitive compositions to the base; Drying processes therefor
- G03C2001/7418—Backup roll
Definitions
- This invention relates to coating methods, and more particularly to a coating method of applying a variety of liquid-phase compound materials to a belt-shaped flexible support (hereinafter referred to as "a web”, when applicable) which is run continuously, to manufacture photographing photo-sensitive materials such as photographing film and photographic paper, photographic printing plate, pressure-sensitive sheets, heat-sensitive sheets, and so forth.
- a web belt-shaped flexible support
- Examples of a conventional coating method in which a web is electrostatically charged to coat it with a coating solution are for instance as follows:
- the first and second coating methods suffer from the following problem: In the case where the surface of the web is relatively large in the number of polar groups; for instance in the case where, as in the case of the second coating method, the web contains surface active agent, the coating condition of the surface of the web is improved which is probably due to the orientation of the polar groups in the surface of the web as well as an electrostatic attraction force provided by the electric field applied thereto, as a result of which the coating speed can be increased.
- the coating condition of the surface of the web is not bettered, and the coating speed cannot be increased so much as expected.
- the surface of the web is made uniform in potential distribution by heating the web which has been electrostatically charged, whereby the difficulty is eliminated that streaks are formed on the coating solution layer on the support.
- the surface potential is lowered, as a result of which it is difficult to maintain the surface potential so high, and the coating speed cannot be increased so much as expected.
- an object of this invention is to eliminate the above-described difficulties accompanying a conventional coating method.
- an object of the invention is to provide a coating method in which, even in the case where the surface of a web is relatively low in the number of polar groups, a relatively high potential can be uniformly applied to the surface of the web, and the critical coating speed can be greatly increased.
- the foregoing object of the invention has been achieved by the provision of a coating method in which a belt-shaped flexible support which is being run continuously is supported on a backup roller, and a coating solution supplied from a coating nozzle is applied to the support; in which, according to the invention, before a coating operation, the support is heated to 35°C to 45°C, and the surface potential of the support on the backup roller set to 0.5 to 2 kV.
- the surface of a web 1 is made single polar by electrostatically charging it by corona discharge.
- the web 1 is heated to 35°C to 45°C while passing through a heating zone 2.
- the web 1 thus heated is electrostatically charged by a corona discharge electrode 7 which is connected to a DC high voltage source 3 and is confronted with a grounding electrode 8, so that the surface of the web is made single polar, having a potential of 0.5 to 2 kV.
- the web 1 thus processed is delivered to a coating backup roller 4 while being maintained sufficiently high in temperature, where a coating solution 6 from a coating nozzle 5 is applied to the web.
- a DC high voltage is applied to a web 1 at a backup roller.
- the web 1 is heated to 35°C to 45°C at a heating zone 2.
- the web 1 thus heated is delivered to a coating backup roller 4 to which a DC high voltage is applied by a DC high voltage source 3, where a coating solution 6 from a coating die 5 is applied to the web 1.
- the web is heated to 35°C to 45°C. This will be described in more detail.
- a coating operation is carried out at a room temperature of 20°C to 25°C.
- the web is heated to 35°C to 45°C by convection by using hot air, or by conduction by bringing it into contact with a high temperature pass roll, or by radiation by using infrared rays. If the temperature of the web thus heated is less than 35°C, then the macromolecules in the surface of the web are greatly limited in mobility, so that the coating speed cannot be increased so much as expected. In addition, when the temperature of the web is higher than 45°C, then the coating solution setting conditions are not satisfied.
- the surface potential of the web on the backup roller is set to 0.5 to 2.0 kV.
- two methods are employed; in the first method, the web is charged by corona discharge; and in the second method, a DC voltage is applied to the backup roller.
- a wire-like conductor 100 ⁇ m to 200 ⁇ m in diameter is laid tight with a tension of 1 kg or higher, and intermediate frames support the wired at points spaced at an interval of not more than 300 mm.
- Each intermediate holding frame is shifted in the longitudinal direction on each wire form a superposed (aligned) position on the wires in the transfer direction with a shift ⁇ 20 mm from the immediately previous adjacent wire so that the distance between the wire-like, electrode and the web is smaller at the end of the wire than at the middle.
- the journal of the backup roller is insulated with a ceramic cover and supported with a fluid bearing, and a connecting terminal other than a brush type slip ring is provided at a rotary part which is an extension of the journal, and connected to the DC high voltage source.
- the rotation is steady.
- a high voltage of 0.5 to 3 kV can be positively applied (cf. Japanese Patent Application (OPI) No. 251266/1990.
- the surface of the web on the backup roller can be set uniformly to 0.5 to 2.0 kV, preferably 0.5 to 1.2 kV.
- the polar groups of macromolecules are orientated in the surface of the web, thus increasing the web's surface energy, which improves the coating conditions.
- the electrostatic attraction force by the electrostatic field facilitates the sticking of the coating solution to the surface of the web.
- the term "belt-shaped flexible support” or "web” as used herein is intended to include those of paper, plastic film, resin-coated paper, and synthetic paper.
- the material of the plastic film are polyolefins such as polyethylene and polypropylene, vinyl copolymers such as polyvinyl acetate, polyvinyl chloride and polystyrene, polyamide such as 6,6-nylon and 6-nylon, polyesters such as polyethylene terephthalate, polyethylene-2, and 6-napthalate, and polycarbonate, and cellulose acetates such as cellulose triacetate and cellulose diacetate.
- An undercoat layer of gelatin may be formed on the web as the case may be.
- the resin employed for manufacture of the resin-coated paper is typically polyolefin such as polyethylene.
- a web of resin-coated paper is not limited in surface roughness; that is, not only a web of resin-coated paper whose surface is smooth, but also one whose surface is rough can be employed.
- the critical coating speed is increased according to the invention.
- coating solution as used herein is intended to include a variety of coating solutions, such as those used to form a photo emulsion layer, undercoat layer, protective layer and a back layer thereby to form a photographing photo-sensitive material, or those for forming an adhesive layer, coloring layer, rust-proofing layer, etc.
- Those coating solutions may contain water-soluble binder, or organic binder.
- a slide coating method for instance a slide coating method, roller bead coating method, spray coating method, extrusion coating method, and curtain coating method may be employed.
- a web was prepared by forming a gelatin layer 0.3 ⁇ m in thickness on a coating surface of a polyethylene resin coated sheet 220 ⁇ m in thickness, and an alumina-sol layer on the rear surface.
- the coating surface had an average surface roughness (Ra) of 4 to 5 ⁇ m.
- the surface of the web was 3 x 10 ⁇ 3 equivalent/m2 in the number of polar groups.
- Color paper coating solutions were employed.
- the layer structure was made up of three photo-sensitive layers containing silver halide, three color filter layers, and one protective layer.
- a total quantity of coating solutions supplied per unitary web area 1 m2 was 106 ml.
- the density of gelatin was 6% by weight, the viscosity was 40 cp (with a shear rate of 50 sec ⁇ 1), and the quantity of supply was 14.4 ml/m2.
- a slide bead coating method was employed.
- the pressure of the pressure reducing chamber was set to a value lower by 40 mm H2O than the atmospheric pressure.
- the gap between the end of the coating nozzle and the web was about 400 ⁇ m.
- a heating method using a hot air at 70°C to 50°C was employed.
- the length of the web in the heating zone was 18 m.
- the temperature of the web which was going to be coated being on the coating backup roller was measured as a web temperature.
- the web was electrostatically charged as shown in FIG. 1.
- the distance between the backup roller 4 and the corona discharge electrode 7 adapted to electrostatically change the web by corona discharge so as to make the web's surface single polar was short, 2 m.
- the web was substantially free from temperature difference.
- the surface potential of the web which was going to be coated being on the coating backup roller was measured as a web temperature.
- the critical speeds were measured when, depending on the web potential and web temperature, an air layer accompanying the web obstructed the application of the coating solution to the web.
- the results of measurement are as indicated in the following Table 1: Table 1 0 kV 0.5 kV 1.0 kV 1.2 kV 22°C 178 m/min 200 m/min 204 m/min 203 m/min 32°C 180 m/min 205 m/min 218 m/min 228 m/min 38°C 195 m/min 240 m/min 248 m/min 260 m/min 45°C 197 m/min 243 m/min 255 m/min 270 m/min
- the web temperatures were 38°C and 45°C, and the web potentials were 0.5 kV, 1.0 kV, and 1.2 kV, as indicated in Table 1.
- the critical coating speed was 200 m/min, as shown in Table 1.
- this critical coating speed was increased to 240 m/min. by raising the web temperature to 38°C according to the invention.
- the critical coating speed was 203 m/min. This critical coating speed was increased to 270 m/min.
- the surface of the product was satisfactory being free from defects such as streaks and non-uniform thickness.
- the coating method of the invention even in the case where the surface of the web is relatively low in the number of polar groups, relatively high potential can be provided uniform on the surface of the web, and the critical coating speed can be greatly increased.
Abstract
Description
- This invention relates to coating methods, and more particularly to a coating method of applying a variety of liquid-phase compound materials to a belt-shaped flexible support (hereinafter referred to as "a web", when applicable) which is run continuously, to manufacture photographing photo-sensitive materials such as photographing film and photographic paper, photographic printing plate, pressure-sensitive sheets, heat-sensitive sheets, and so forth.
- Examples of a conventional coating method in which a web is electrostatically charged to coat it with a coating solution, are for instance as follows:
- (1) First coating method: In coating a web with a coating solution, a DC, AC or pulse high voltage (300 to 2000 volts) is applied between a coating nozzle and a backup roller supporting the web, thereby to prevent discontinuation of the bead between the web and the coating nozzle (British Patent No. 1,166,500-B).
- (2) Second coating method: In coating a web having a undercoat layer of gelatin containing surface active agent, similarly as in the first coating method a DC high voltage is applied to the backup roller (US Patent No.4,837,045).
- (3) Third coating method: The web is processed in advance as follows: That is, the web is electrostatically charged by corona discharge, and is heated to make the distribution of electrostatic charges uniform, and then cooled. The web thus processed is coated with a coating solution. When the web is coated in this manner, no streaks are formed on the resultant coating solution layer on the web. That is, the third coating method is to eliminate the difficulty that streaks are formed on the coating solution layer on the web.
- The first and second coating methods suffer from the following problem: In the case where the surface of the web is relatively large in the number of polar groups; for instance in the case where, as in the case of the second coating method, the web contains surface active agent, the coating condition of the surface of the web is improved which is probably due to the orientation of the polar groups in the surface of the web as well as an electrostatic attraction force provided by the electric field applied thereto, as a result of which the coating speed can be increased. On the other hand, in the case where the surface of the web is relatively small in the number of polar groups (the number of polar groups per unitary area of the part of the web which is 1 µm in thickness from the surface being 4 x 10⁻³ equivalent/m² or less), the coating condition of the surface of the web is not bettered, and the coating speed cannot be increased so much as expected.
- In the third coating method, the surface of the web is made uniform in potential distribution by heating the web which has been electrostatically charged, whereby the difficulty is eliminated that streaks are formed on the coating solution layer on the support. However, in the part of the web which is heated, the surface potential is lowered, as a result of which it is difficult to maintain the surface potential so high, and the coating speed cannot be increased so much as expected.
- Accordingly, an object of this invention is to eliminate the above-described difficulties accompanying a conventional coating method.
- More specifically., an object of the invention is to provide a coating method in which, even in the case where the surface of a web is relatively low in the number of polar groups, a relatively high potential can be uniformly applied to the surface of the web, and the critical coating speed can be greatly increased.
- The foregoing object of the invention has been achieved by the provision of a coating method in which a belt-shaped flexible support which is being run continuously is supported on a backup roller, and a coating solution supplied from a coating nozzle is applied to the support; in which, according to the invention, before a coating operation, the support is heated to 35°C to 45°C, and the surface potential of the support on the backup roller set to 0.5 to 2 kV.
- The nature, principle, and utility of the invention will be more clearly understood from the following detailed description of the invention when read in conjunction with the accompanying drawing.
- In the accompanying drawing:
- FIG. 1 is a side view outlining the arrangement of one example of a coating apparatus practicing a coating method of the invention; and
- FIG. 2 is also a side view outlining the arrangement of another example of the coating apparatus practicing the coating method of the invention.
- With a coating apparatus shown in FIG. 1, the surface of a web 1 is made single polar by electrostatically charging it by corona discharge. The web 1 is heated to 35°C to 45°C while passing through a
heating zone 2. The web 1 thus heated is electrostatically charged by a corona discharge electrode 7 which is connected to a DChigh voltage source 3 and is confronted with a grounding electrode 8, so that the surface of the web is made single polar, having a potential of 0.5 to 2 kV. The web 1 thus processed is delivered to acoating backup roller 4 while being maintained sufficiently high in temperature, where acoating solution 6 from acoating nozzle 5 is applied to the web. - In the case of FIG. 2, a DC high voltage is applied to a web 1 at a backup roller. Similarly as in the case of FIG. 1, the web 1 is heated to 35°C to 45°C at a
heating zone 2. The web 1 thus heated is delivered to acoating backup roller 4 to which a DC high voltage is applied by a DChigh voltage source 3, where acoating solution 6 from acoating die 5 is applied to the web 1. - As was described above, in the coating method of the invention, the web is heated to 35°C to 45°C. This will be described in more detail.
- Heretofore, a coating operation is carried out at a room temperature of 20°C to 25°C. In the invention, the web is heated to 35°C to 45°C by convection by using hot air, or by conduction by bringing it into contact with a high temperature pass roll, or by radiation by using infrared rays. If the temperature of the web thus heated is less than 35°C, then the macromolecules in the surface of the web are greatly limited in mobility, so that the coating speed cannot be increased so much as expected. In addition, when the temperature of the web is higher than 45°C, then the coating solution setting conditions are not satisfied.
- Furthermore, in the coating method of the invention, the surface potential of the web on the backup roller is set to 0.5 to 2.0 kV. For this purpose, two methods are employed; in the first method, the web is charged by corona discharge; and in the second method, a DC voltage is applied to the backup roller.
- In the first method, preferably a wire-like conductor 100 µm to 200 µm in diameter is laid tight with a tension of 1 kg or higher, and intermediate frames support the wired at points spaced at an interval of not more than 300 mm. Each intermediate holding frame is shifted in the longitudinal direction on each wire form a superposed (aligned) position on the wires in the transfer direction with a shift ≧ 20 mm from the immediately previous adjacent wire so that the distance between the wire-like, electrode and the web is smaller at the end of the wire than at the middle. In this case, the variations in potential in the direction of conveyance of the web and in the direction of width of the latter can be minimized, and therefore, the difficulty can be substantially eliminated that the coating solution layer becomes non-uniform in thickness because of the variations in potential (US Patent No. 5,138,971).
- In the case of the second method, it is preferable that the journal of the backup roller is insulated with a ceramic cover and supported with a fluid bearing, and a connecting terminal other than a brush type slip ring is provided at a rotary part which is an extension of the journal, and connected to the DC high voltage source. In the second method, when compared with the conventional method in which a ball bearing is employed, the rotation is steady. Further-more, when compared with the case where the brush-type slip ring is employed, a high voltage of 0.5 to 3 kV can be positively applied (cf. Japanese Patent Application (OPI) No. 251266/1990.
- Employment of the above-described two methods in combination, the surface of the web on the backup roller can be set uniformly to 0.5 to 2.0 kV, preferably 0.5 to 1.2 kV. As a result, the polar groups of macromolecules are orientated in the surface of the web, thus increasing the web's surface energy, which improves the coating conditions. In addition, the electrostatic attraction force by the electrostatic field facilitates the sticking of the coating solution to the surface of the web.
- In the invention, the term "belt-shaped flexible support" or "web" as used herein is intended to include those of paper, plastic film, resin-coated paper, and synthetic paper. Examples of the material of the plastic film are polyolefins such as polyethylene and polypropylene, vinyl copolymers such as polyvinyl acetate, polyvinyl chloride and polystyrene, polyamide such as 6,6-nylon and 6-nylon, polyesters such as polyethylene terephthalate, polyethylene-2, and 6-napthalate, and polycarbonate, and cellulose acetates such as cellulose triacetate and cellulose diacetate. An undercoat layer of gelatin may be formed on the web as the case may be. The resin employed for manufacture of the resin-coated paper is typically polyolefin such as polyethylene. A web of resin-coated paper is not limited in surface roughness; that is, not only a web of resin-coated paper whose surface is smooth, but also one whose surface is rough can be employed.
- Even in the case where the web is such that its surface is relatively low in the number of polar groups (the number of polar groups per unitary area of the part of the web which is 1 µm in thickness from the surface being 4 x 10⁻³ equivalent/m² or less), the occurrence of an air entrainment phenomenon (obstructing the application of a coating solution to a web) which limits the critical coating speed is prevented accordingly to the invention. That is, the critical coating speed is increased according to the invention.
- The term "coating solution" as used herein is intended to include a variety of coating solutions, such as those used to form a photo emulsion layer, undercoat layer, protective layer and a back layer thereby to form a photographing photo-sensitive material, or those for forming an adhesive layer, coloring layer, rust-proofing layer, etc. Those coating solutions may contain water-soluble binder, or organic binder.
- In applying the coating solution to the web, for instance a slide coating method, roller bead coating method, spray coating method, extrusion coating method, and curtain coating method may be employed.
- As conducive to a full understanding of the invention, its concrete example will be described. However, it should be noted that the invention is not limited thereto or thereby.
- A web was prepared by forming a gelatin layer 0.3 µm in thickness on a coating surface of a polyethylene resin coated sheet 220 µm in thickness, and an alumina-sol layer on the rear surface. The coating surface had an average surface roughness (Ra) of 4 to 5 µm. The surface of the web was 3 x 10⁻³ equivalent/m² in the number of polar groups.
- Color paper coating solutions were employed. The layer structure was made up of three photo-sensitive layers containing silver halide, three color filter layers, and one protective layer. A total quantity of coating solutions supplied per unitary web area 1 m² was 106 ml. As for the lowermost layer, namely, a yellow coloring layer, the density of gelatin was 6% by weight, the viscosity was 40 cp (with a shear rate of 50 sec⁻¹), and the quantity of supply was 14.4 ml/m².
- A slide bead coating method was employed. The pressure of the pressure reducing chamber was set to a value lower by 40 mm H₂O than the atmospheric pressure. The gap between the end of the coating nozzle and the web was about 400 µm.
- A heating method using a hot air at 70°C to 50°C was employed. The length of the web in the heating zone was 18 m. The temperature of the web which was going to be coated being on the coating backup roller was measured as a web temperature.
- The web was electrostatically charged as shown in FIG. 1. In this operation, the distance between the
backup roller 4 and the corona discharge electrode 7 adapted to electrostatically change the web by corona discharge so as to make the web's surface single polar was short, 2 m. Thus, the web was substantially free from temperature difference. - The surface potential of the web which was going to be coated being on the coating backup roller was measured as a web temperature. The critical speeds were measured when, depending on the web potential and web temperature, an air layer accompanying the web obstructed the application of the coating solution to the web. The results of measurement are as indicated in the following Table 1:
Table 1 0 kV 0.5 kV 1.0 kV 1.2 kV 22°C 178 m/min 200 m/min 204 m/min 203 m/min 32°C 180 m/min 205 m/min 218 m/min 228 m/min 38°C 195 m/min 240 m/min 248 m/min 260 m/min 45°C 197 m/min 243 m/min 255 m/min 270 m/min - In the concrete example, the web temperatures were 38°C and 45°C, and the web potentials were 0.5 kV, 1.0 kV, and 1.2 kV, as indicated in Table 1. In the prior art, with 22°C and 0.5 kV, the critical coating speed was 200 m/min, as shown in Table 1. However, this critical coating speed was increased to 240 m/min. by raising the web temperature to 38°C according to the invention. In addition, in the prior art, with 22°C and 1.2 kV, the critical coating speed was 203 m/min. This critical coating speed was increased to 270 m/min.
- Furthermore, in the concrete example, the surface of the product was satisfactory being free from defects such as streaks and non-uniform thickness.
- As is apparent from the above-description, according to the coating method of the invention, even in the case where the surface of the web is relatively low in the number of polar groups, relatively high potential can be provided uniform on the surface of the web, and the critical coating speed can be greatly increased.
- While there has been described in connection with the preferred embodiment of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is aimed, therefore, to cover in the appended claim all such changes and modifications as fall within the true spirit and scope of the invention.
Claims (2)
- A coating apparatus comprising:
a backup roller;
a belt shaped flexible support supported on said backup roller;
heating means for heating said belt-shaped flexible support from 35° to 45°;
discharging means for setting a surface potential of said belt-shaped flexible support from 0.5 to 2kv; and
a coating nozzle applying a coating solution onto a surface of said belt-shaped flexible support,
wherein said heating means is disposed upstream said discharging means and said coating nozzle is arranged downstream said discharging means. - A method for supplying a coating solution onto a belt-shaped flexible support which is being run continuously, said belt-shaped flexible support supported on a backup roller, and said coating solution which is supplied from a coating nozzle, is applied to said support, comprising the steps of:
heating said support from 35°C to 45°C;
setting a surface potential of said support on said backup roller to 0.5 to 2kv; and
applying said coating solution onto said support.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3246476A JP2835659B2 (en) | 1991-09-02 | 1991-09-02 | Application method |
JP246476/91 | 1991-09-02 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0530752A1 true EP0530752A1 (en) | 1993-03-10 |
EP0530752B1 EP0530752B1 (en) | 1999-01-13 |
Family
ID=17148973
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19920114937 Expired - Lifetime EP0530752B1 (en) | 1991-09-02 | 1992-09-01 | Coating apparatus and method |
Country Status (3)
Country | Link |
---|---|
EP (1) | EP0530752B1 (en) |
JP (1) | JP2835659B2 (en) |
DE (1) | DE69228160T2 (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5609923A (en) * | 1995-02-25 | 1997-03-11 | Eastman Kodak Company | Method of curtain coating a moving support wherein the maximum practical coating speed is increased |
EP0836117A2 (en) * | 1996-10-09 | 1998-04-15 | Fuji Photo Film Co., Ltd. | Curtain coating method |
EP0945756A1 (en) * | 1998-03-25 | 1999-09-29 | Agfa-Gevaert N.V. | A method for preparing an imaging element for making an improved printing plate according to the silver salt diffusion transfer process |
US6040109A (en) * | 1998-03-25 | 2000-03-21 | Agfa-Gevaert, N.V. | Method for preparing an image element for making an improved printing plate according to the silver salt diffusion transfer process |
US6127003A (en) * | 1997-10-31 | 2000-10-03 | Konica Corporation | Method of coating a substrate including a charging step and apparatus for carrying out the method |
US6177141B1 (en) * | 1998-11-03 | 2001-01-23 | Eastman Kodak Company | Method for coating a liquid composition to a web using a backing roller with a relieved surface |
US6305854B1 (en) | 1998-12-23 | 2001-10-23 | Eastman Kodak Company | Relating to photographic processes |
US6368675B1 (en) | 2000-04-06 | 2002-04-09 | 3M Innovative Properties Company | Electrostatically assisted coating method and apparatus with focused electrode field |
US6475572B2 (en) | 2000-04-06 | 2002-11-05 | 3M Innovative Properties Company | Electrostatically assisted coating method with focused web-borne charges |
US6511711B2 (en) | 2000-12-21 | 2003-01-28 | Eastman Kodak Company | Slide bead coating method |
US6572516B2 (en) | 1998-12-23 | 2003-06-03 | Eastman Kodak Company | Device to reduce electrostatic pattern transfer in coating processes |
WO2003064766A2 (en) * | 2002-01-31 | 2003-08-07 | Raisio Chemicals Ltd | A coating method involving the use of an electrical field |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP4175778B2 (en) | 2001-01-18 | 2008-11-05 | 富士フイルム株式会社 | Application method |
JP4326711B2 (en) | 2001-02-28 | 2009-09-09 | 富士フイルム株式会社 | Curtain application method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0055983A2 (en) * | 1981-01-05 | 1982-07-14 | Polaroid Corporation | Electrostatically assisted coating gap |
EP0299492A2 (en) * | 1987-07-17 | 1989-01-18 | Fuji Photo Film Co., Ltd. | Method and apparatus for applying a coating liquid to a moving web |
EP0386796A2 (en) * | 1989-03-10 | 1990-09-12 | Fuji Photo Film Co., Ltd. | Method of applying single polar electrostatic charges to continously travelling long web support, and apparatus practicing same |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61146370A (en) * | 1984-12-18 | 1986-07-04 | Konishiroku Photo Ind Co Ltd | Coating method |
JPS61161177A (en) * | 1985-01-11 | 1986-07-21 | Fuji Photo Film Co Ltd | Method for feeding electricity to backup roller for coating |
JPH0627928B2 (en) * | 1985-06-04 | 1994-04-13 | 富士写真フイルム株式会社 | Method for producing photographic light-sensitive material |
-
1991
- 1991-09-02 JP JP3246476A patent/JP2835659B2/en not_active Expired - Lifetime
-
1992
- 1992-09-01 EP EP19920114937 patent/EP0530752B1/en not_active Expired - Lifetime
- 1992-09-01 DE DE1992628160 patent/DE69228160T2/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0055983A2 (en) * | 1981-01-05 | 1982-07-14 | Polaroid Corporation | Electrostatically assisted coating gap |
EP0299492A2 (en) * | 1987-07-17 | 1989-01-18 | Fuji Photo Film Co., Ltd. | Method and apparatus for applying a coating liquid to a moving web |
EP0386796A2 (en) * | 1989-03-10 | 1990-09-12 | Fuji Photo Film Co., Ltd. | Method of applying single polar electrostatic charges to continously travelling long web support, and apparatus practicing same |
Non-Patent Citations (3)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 10, no. 366 (C-390) 6 December 1986 & JP-A-61 161 177 ( FUJI PHOTO FILM CO LTD ) 21 July 1986 * |
PATENT ABSTRACTS OF JAPAN vol. 14, no. 530 (P-1134) 21 November 1990 & JP-A-02 223 945 ( FUJI PHOTO FILM CO LTD ) 6 September 1990 * |
PATENT ABSTRACTS OF JAPAN vol. 3, no. 77 (E-120) 30 June 1979 & JP-A-54 054 020 ( FUJI PHOTO FILM CO LTD ) 27 April 1979 * |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5609923A (en) * | 1995-02-25 | 1997-03-11 | Eastman Kodak Company | Method of curtain coating a moving support wherein the maximum practical coating speed is increased |
EP0836117A2 (en) * | 1996-10-09 | 1998-04-15 | Fuji Photo Film Co., Ltd. | Curtain coating method |
EP0836117A3 (en) * | 1996-10-09 | 1998-07-08 | Fuji Photo Film Co., Ltd. | Curtain coating method |
US6127003A (en) * | 1997-10-31 | 2000-10-03 | Konica Corporation | Method of coating a substrate including a charging step and apparatus for carrying out the method |
EP0945756A1 (en) * | 1998-03-25 | 1999-09-29 | Agfa-Gevaert N.V. | A method for preparing an imaging element for making an improved printing plate according to the silver salt diffusion transfer process |
US6040109A (en) * | 1998-03-25 | 2000-03-21 | Agfa-Gevaert, N.V. | Method for preparing an image element for making an improved printing plate according to the silver salt diffusion transfer process |
US6177141B1 (en) * | 1998-11-03 | 2001-01-23 | Eastman Kodak Company | Method for coating a liquid composition to a web using a backing roller with a relieved surface |
US6572516B2 (en) | 1998-12-23 | 2003-06-03 | Eastman Kodak Company | Device to reduce electrostatic pattern transfer in coating processes |
US6305854B1 (en) | 1998-12-23 | 2001-10-23 | Eastman Kodak Company | Relating to photographic processes |
US6368675B1 (en) | 2000-04-06 | 2002-04-09 | 3M Innovative Properties Company | Electrostatically assisted coating method and apparatus with focused electrode field |
US6475572B2 (en) | 2000-04-06 | 2002-11-05 | 3M Innovative Properties Company | Electrostatically assisted coating method with focused web-borne charges |
US6666918B2 (en) | 2000-04-06 | 2003-12-23 | 3M Innovative Properties Company | Electrostatically assisted coating apparatus with focused web charge field |
US6716286B2 (en) | 2000-04-06 | 2004-04-06 | 3M Innovative Properties Company | Electrostatically assisted coating method and apparatus with focused electrode field |
US6511711B2 (en) | 2000-12-21 | 2003-01-28 | Eastman Kodak Company | Slide bead coating method |
WO2003064766A2 (en) * | 2002-01-31 | 2003-08-07 | Raisio Chemicals Ltd | A coating method involving the use of an electrical field |
WO2003064766A3 (en) * | 2002-01-31 | 2003-11-13 | Raisio Chem Ltd | A coating method involving the use of an electrical field |
Also Published As
Publication number | Publication date |
---|---|
JP2835659B2 (en) | 1998-12-14 |
DE69228160T2 (en) | 1999-05-20 |
EP0530752B1 (en) | 1999-01-13 |
JPH0561151A (en) | 1993-03-12 |
DE69228160D1 (en) | 1999-02-25 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0530752B1 (en) | Coating apparatus and method | |
US5340616A (en) | A coating method using an electrified web and increased humidity | |
US4835004A (en) | Method and apparatus for applying a coating liquid to a moving web | |
US5295039A (en) | Method of applying single polar electro-static charges to continuously travelling long web support, and apparatus practicing same | |
US4837045A (en) | Coating method | |
JPH0677711B2 (en) | Coating device | |
US4340621A (en) | Method for preventing formation of a heavy liquid layer on a web at a coating start position | |
JP2632265B2 (en) | Joint application method | |
US5122386A (en) | Double side coating method | |
JPH0627928B2 (en) | Method for producing photographic light-sensitive material | |
EP1238712B1 (en) | System for coating using a grooved backing roller and electrostatic assist | |
EP0969314B1 (en) | Curtain coating method | |
JP2000093868A (en) | Device and method for curtain coating | |
JP2003530214A (en) | Electrostatic assist coating method and apparatus with focused web charge | |
EP0404014A2 (en) | Coating width changing device for use in curtain coating | |
JP2001113216A (en) | Coating product, coating production apparatus, and coating production method | |
US6511711B2 (en) | Slide bead coating method | |
US20030059548A1 (en) | Method for using a patterned backing roller for curtain coating a liquid composition to a web | |
JP3912769B2 (en) | Application method and application line | |
US20040085705A1 (en) | Electrostatic charge neutralization using grooved roller surface patterns | |
US5458925A (en) | Dual geometry for slide-bead coating | |
JP2890219B2 (en) | Application method | |
JPS61146369A (en) | Coating method | |
US20020132058A1 (en) | Method for coating web | |
JPH03161A (en) | Coating method |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): DE IE NL |
|
17P | Request for examination filed |
Effective date: 19930909 |
|
17Q | First examination report despatched |
Effective date: 19970321 |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
RBV | Designated contracting states (corrected) |
Designated state(s): DE NL |
|
GRAG | Despatch of communication of intention to grant |
Free format text: ORIGINAL CODE: EPIDOS AGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAH | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOS IGRA |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE NL |
|
REF | Corresponds to: |
Ref document number: 69228160 Country of ref document: DE Date of ref document: 19990225 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20110803 Year of fee payment: 20 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 20110922 Year of fee payment: 20 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R071 Ref document number: 69228160 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R071 Ref document number: 69228160 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: NL Ref legal event code: V4 Effective date: 20120901 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20120904 |