TWI248107B - Formation method for coated layers, production method for a lamp and production device for a lamp - Google Patents

Abstract

A formation method for coated layers is provided, which can attain the uniformity of the film-thickness of the coated layers formed on the pipe inner-wall surface, and a production method for a lamp as well as a production device for a lamp are also provided, which can attain the uniformity of the brightness. In a heating process, a glass-pipe 5 is held perpendicularly or nearly perpendicularly, hot wind is blown from the upper opening of the glass-pipe 5 towards the inner side, so that the upper section of the glass-pipe 5 is uniformly heated in the circumference direction. Next, in a coating process, after the coating liquid 14 is attracted from the lower end of the glass-pipe 5, the attraction is released and the coating liquid 14 is removed, and then the coating liquid 14 is attached to the inner-wall surface of the glass-pipe 5. Then, in a drying process, the glass-pipe 5 is rotated with its axis as the center and air is blown towards the inner side of the glass-pipe 5, thus the attached coating liquid 14 is dried and the coated layer is formed.

Description

[Technical Field] The present invention relates to a method for forming a coating layer for forming a coating layer on an inner wall surface of a glass tube, and is provided in a cold cathode tube or the like. Fluorescent film manufacturing method and lamp manufacturing apparatus. [Prior Art] As a backlight using a liquid crystal display device or the like, a cold cathode fluorescent lamp (C C F L ) is generally used. The lamp tube is provided at a predetermined portion of the inner wall surface, and has an electric H-electrode on both ends of the glass tube on which the fluorescent film has been formed, and an inert gas and mercury vapor are sealed in the glass tube. In the past, a fluorescent film was formed on the inner wall surface of a glass tube. First, a coating layer containing a fluorescent material was formed. Further, a fluorescent film is formed by firing a coating layer. In the formation of the coating film layer, the coating liquid is sucked up from the lower end of the glass tube which is maintained in a vertical direction. Next, the sucked coating liquid is discharged from the lower end of the aforementioned glass tube. Thereby, the coating liquid is adhered to the inner wall surface of the glass tube. Further, a method of blowing dry air from the opening at the upper end of the glass tube and drying the applied coating liquid is also employed. β In the above method, the coating liquid adhering to the inner wall surface of the glass tube is slid before drying, and the film thickness of the coating layer is formed thinner on the upper portion of the glass tube and thicker at the lower portion of the glass tube. . Therefore, there is a difference in the film thickness of the fluorescent film, and there is even a problem that the brightness of the tube is unevenly formed. In order to promote the drying of the coating liquid and to reduce the slippage, there is a method in which the upper portion of the glass tube is heated by the hot air blown from the nozzle by 1248107 during drying (for example, refer to the patent). Literature 1). [Patent Document 1] Japanese Patent Laid-Open Publication No. 2 0 0 2 - 3 4 3 2 4 6 . [Problems to be Solved by the Invention] However, even in the structure described in the above-mentioned patent document, the suction from the glass tube and the discharge of the coating liquid are started until the temperature of the glass tube is raised by hot air. During this period, there will be a coating liquid that adheres to the inner wall surface of the glass tube. Therefore, there is still a case where the film thickness of the coating layer on the upper portion of the glass tube is formed to be thin. Further, since the nozzle is disposed outside the glass tube, it is formed to be locally heated by a direction on the circumference of the glass tube. Therefore, uneven heating occurs in the circumferential direction of the glass tube, and the film thickness of the coating layer having the circumferential direction of the glass tube is not uniform. The present invention has been made in view of the above circumstances, and an object thereof is to provide a coating layer forming method capable of uniformizing a film thickness of a coating layer formed on an inner wall surface of a tube, and to achieve a more uniform brightness. The luminaire manufacturing method and the luminaire manufacturing device. SUMMARY OF THE INVENTION The following description is directed to various methods for solving the above-described objects and the like. In addition, if necessary, a special effect is attached to the corresponding method. Method 1: A method for forming a coating layer, characterized in that: the heating program 'is heating from the inside of the glass tube; and the coating procedure is to maintain the heated glass tube in a vertical or slightly vertical state, The coating 1248107 is adhered to the inner wall surface of the glass tube; the drying procedure 'forms the coating layer by drying the adhered coating liquid. The glass tube is heated inside for the heating process in the stage of the coating process by the above method. Therefore, in the coating process, the glass tube is preheated, and drying is started from the point of time when the coating liquid is attached. Thus, the attached coating liquid is difficult to slip down as compared with the past. Therefore, unlike the conventional technique in which the coating liquid is slipped before the glass tube is heated and the upper film thickness is thinned in the drying process, the thinning of the upper film thickness of the glass tube can be prevented, and the tube can be reached. The difference in film thickness in the axial direction is reduced. Further, since the heating is performed from the inside of the glass tube, it is easy to reduce the heating unevenness in the circumferential direction as compared with the case where the heating is started from the outside. Therefore, the difference in film thickness in the circumferential direction can be easily reduced. Method 2: A method for forming a coating layer, comprising: heating a step of heating the inner side of one end of the glass tube; and applying a step of setting the one end side to an upper side by maintaining the glass tube vertically or In a state of being slightly vertical, the coating liquid is adhered to the inner wall surface of the glass tube; and a drying process is performed to form a coating layer by drying the adhered coating liquid. According to the second method described above, the heating process in the stage before the coating process is such that the glass tube is heated from the inside. Therefore, in the coating process, the glass tube is heated in advance, and drying is started from the point of time when the coating liquid has adhered. Therefore, compared with the conventional one, the applied coating liquid is difficult to slip. In addition, since the heated end is set to the upper side, the higher the glass tube system is, the higher the temperature is formed, so that it is easy.

Promote drying. Therefore, unlike the conventional technique in which the coating liquid is slid down and the upper film thickness is thinned in the drying process, the thinning of the upper film thickness of the glass tube can be prevented, and the tube can be reached. The difference in film thickness in the axial direction is reduced. Further, the lower portion of the glass tube is lower in temperature than the upper portion, and thus will not be as fast as the upper portion. Therefore, it is possible to prevent an unreasonable promotion of drying of the coating liquid to be slid and to increase the thickness of the coating layer. Further, since the heating is performed from the inside of the glass tube, it is easy to reduce the heating unevenness in the circumferential direction as compared with the case where the heating is performed from the outside. Therefore, the difference in film thickness in the circumferential direction can be reduced. A method of forming a coating layer according to the second aspect, characterized in that in the heating process, hot air is blown from an opening at an upper end of the glass tube.

According to the third method described above, the glass tube can be formed to be more uniformly heated in the circumferential direction by blowing hot air from the upper end opening of the glass tube. Therefore, unlike the case where hot air is blown in a part from the outer side of the glass tube, it is difficult to cause uneven heating in the circumferential direction of the tube. Therefore, the film thickness of the coating layer in the circumferential direction of the tube can be made more uniform. Method 4: A method for forming a coating layer according to the method 2, characterized in that the temperature difference between one end and the other end of the heated glass tube is formed to be 20 ° C or higher immediately before the coating procedure. . Method 5: A method for forming a coating layer as described in the third method, characterized in that the temperature difference between one end and the other end of the heated glass tube is formed to be 20 ° C or higher immediately before the coating procedure. . According to the above method 4 and method 5, the temperature difference between one end and the other end of the glass tube, that is, between the upper end and the lower end, is formed at 20 ° C or higher immediately before the coating process of 1248107. Therefore, in the upper part of the glass tube, the temperature can be set to a high temperature and the drying can be promoted. Therefore, it is possible to more reliably prevent the thickness of the upper portion of the glass tube from being thinned, and it is possible to further reduce the difference in film thickness in the tube axis direction. Method 6: A method for forming a coating layer, comprising: a heating program for maintaining a glass tube perpendicular or slightly vertical, and blowing hot air toward the inside from an opening at an upper end of the glass tube; The coating liquid is flowed from the upper end of the heated glass tube, and after the coating liquid is adsorbed from the lower end, the coating liquid is adhered to the inner wall surface of the glass tube; the drying process is performed to make the foregoing The glass tube to which the coating liquid is attached is rotated about the tube axis, and the applied coating liquid is dried to form a coating layer by blowing air into the inside of the glass tube. According to the above method 6, in the heating process in the stage before the coating process, the glass tube is heated from the inside by blowing hot air from the upper end portion of the glass tube toward the inside. Next, in the coating process, the coating liquid is allowed to flow down from the upper end of the glass tube, and the coating liquid is adsorbed from the lower end to be discharged, whereby the coating liquid adheres to the inner wall surface of the glass tube. Further, in the drying process, the remaining coating liquid can be smoothly and uniformly discharged by rotating the glass tube, and at the same time, air is blown into the inside of the glass tube to dry the applied coating liquid to form a coating. Membrane layer. As described above, in the coating step, the glass tube is heated in advance, and drying is started from the point of time when the coating liquid has been attached. Therefore, compared with the prior art, the coating liquid to which the upper portion has been attached is difficult to slip, and the glass tube 1248107 is formed to be higher in temperature, and the drying can be easily promoted. Therefore, unlike the prior art, in the drying process, the coating liquid is caused to slip off before the glass tube is heated, so that the upper film thickness is thinned, so that the thickness of the upper portion of the glass tube can be prevented from being thinned, and the tube can be reached. The difference in film thickness in the axial direction is reduced. Further, since the lower portion of the glass tube is lower in temperature than the upper portion, it does not dry as quickly as the above. Therefore, it is possible to prevent an unreasonable promotion of drying of the coating liquid to be slid and to increase the thickness of the coating layer. Further, in the above heating procedure, the glass tube is formed to be heated more uniformly in the circumferential direction. Therefore, unlike the case where hot air is blown in a part from the outer side of the glass tube, it is difficult to cause uneven heating in the circumferential direction of the tube. Therefore, the film thickness of the coating layer in the circumferential direction of the tube can be made more uniform. Method 7 is a method for producing a luminaire, which is a method for forming a coating layer according to any one of the methods 1 to 6. The luminescent film can be formed by the coating layer forming method according to any one of the methods 1 to 6, as described in the above method 7. Thereby, the film thickness unevenness of the film is alleviated, and the brightness of the lamp can be made more uniform. (Embodiment 8) A device for manufacturing a lamp having a coating layer forming device for forming a coating layer on an inner wall surface of a glass tube, wherein the coating layer forming device is provided with a heating device for The inner side of one end side of the glass tube is heated; the maintaining device is such that the one end side is set to the upper side, and the glass tube is maintained to be vertical or slightly vertical; the coating device is heated to serve the coating The liquid adheres to the inner wall surface of the glass tube; and the drying device is for drying the inside of the glass tube. -10- 1248107 According to the above method 8, in the coating film forming apparatus, first, the glass tube is heated by the inside of one end side thereof by the heating means. After heating, the one end side is set to the upper side by the holding means, and the glass tube which is maintained vertically or vertically is attached to the inner wall surface of the glass tube by the coating means. . Further, the coating liquid is dried by a drying device, whereby a coating layer is formed on the inner wall surface of the glass tube. In the luminaire manufacturing apparatus, a luminaire using a glass tube having a coating layer formed thereon is manufactured by the above-described coating film forming apparatus. As described above, the glass tube is heated from the inside by the heating means in advance. Therefore, by the coating device, drying is started from the point of time when the coating liquid has been attached. Thus, the attached coating liquid is difficult to slip off in comparison with the conventional one. Further, since one of the heated ends is set to the upper side by the holding means, the higher the temperature of the glass tube is, the higher the temperature is, and the drying can be easily promoted. Therefore, unlike the conventional technique in which the coating liquid is slipped before the glass tube is heated, and the upper film thickness is thinned, the thickness of the upper portion of the glass tube can be prevented from being thinned, and the film thickness in the tube axis direction can be achieved. The reduction of differences. Further, since the lower portion of the glass tube is lower in temperature than the upper portion, it will not dry as quickly as the above. Therefore, it is possible to prevent an unreasonable promotion of the drying of the coating liquid to be slid and to increase the thickness of the coating layer. Further, since heating is performed from the inside of the glass tube, it is easy to reduce heating unevenness in the circumferential direction as compared with heating from the outside. Therefore, the difference in film thickness in the circumferential direction can be reduced. Method 9: A device for manufacturing a lamp having a coating layer forming device for forming a coating layer on an inner wall surface of a glass tube, wherein the coating layer forming device of the above-mentioned -11-1248107 is provided with: a heating device a heating device for blowing hot air toward the inside from the opening of one end of the glass tube and heating; the maintaining device is configured to set the one end side as an upper side for maintaining the glass tube vertically or slightly vertical; After heating, the coating liquid is attached to the inner wall surface of the glass tube; the rotating device is configured to rotate the glass tube around the tube axis; and the drying device is configured to direct air toward the glass The inside of the tube is blown in to dry the inside of the glass tube.

According to the above-described method 9, in the coating film forming apparatus, first, the hot air is blown inwardly from the opening end of the glass tube by the heating means, whereby the circumferential direction of the glass tube is more uniformly heated. After heating, the coating tube is adhered to the glass tube by the coating device with respect to the glass tube which is provided on the upper side by the holding means and is maintained in a vertical or slightly vertical shape. Wall. Further, when the glass tube is rotated about the tube axis by the rotating means, the remaining coating liquid is smoothly and uniformly discharged. Further, air is blown into the inside of the glass tube by the drying means in conjunction with the aforementioned rotation, whereby the coating liquid is dried. Thereby, a coating layer is formed on the inner wall surface of the glass tube. In the luminaire manufacturing apparatus, a luminaire using a glass tube in which a coating layer has been formed is manufactured by the above-described coating film forming apparatus. As described above, the glass tube is heated from the inside by the heating means in advance. Therefore, by the coating device, drying is started from the point of time when the coating liquid has been attached. Thus, in contrast to conventional practices, the applied coating liquid is difficult to slip. Further, since the one end of the heated one is set to the upper side by the holding means, the higher the temperature of the glass tube is, the higher the temperature is, and the drying can be easily promoted. Therefore, unlike in warming glass -12-1248107

A conventional technique in which the coating liquid is slipped and the upper film thickness is thinned before the tube is formed, so that the thickness of the upper portion of the glass tube can be prevented from being reduced, and the difference in film thickness in the tube axis direction can be reduced. Furthermore, since the lower portion of the glass tube is lower in temperature than the upper portion, it will not dry as quickly as above. Therefore, it is possible to prevent the irrational promotion of the drying of the coating liquid to be slid and to increase the thickness of the coating layer. Further, since hot air is blown into the inside of the glass tube, it is easy to reduce heating unevenness in the circumferential direction as compared with heating from the outside. Therefore, it is also easy to achieve a reduction in the film thickness difference in the circumferential direction. [Embodiment]

Hereinafter, an embodiment will be described with reference to the drawings. As shown in Fig. 2, the cold cathode fluorescent tube 1 constituting the lamp of the present embodiment is provided with a sensor portion 2 formed of a glass tube, and is provided in a sealed state at both ends of the sensor portion 2. Electrode holder 3. A fluorescent film 4 is attached to the inner wall surface of the sensor unit 2, and an inert gas and mercury vapor are sealed inside the sensor unit 2. Further, the sensor portion 2 is a relatively elongated member, for example, having an outer diameter of about 3 m to 4 m and a length of about 900 mm to about 130 mm. Of course, the structure can also be deviated from the above range. This type of cold cathode fluorescent lamp 1 is manufactured by the following means by using a designated manufacturing apparatus. That is, first, a coating layer containing a phosphor on the composition is formed on a predetermined portion of the inner wall surface of the glass tube. Further, the phosphor film 4 is formed by firing a coating layer. The reduced diameter portion is formed at two locations along the longitudinal direction of the glass tube in which the fluorescent film 4 has been formed. Next, -13-1248107 is sealed on the end of one of the glass tubes after positioning the electrode holder 3. Next, the other electrode holder 3 and the mercury alloy member are inserted into the other end portion, and the other electrode holders 3 are temporarily stopped against one of the reduced diameter portions, and the mercury alloy member is temporarily stopped by the other reduced diameter portion. (The reduced diameter portion located on the other end side). Thereafter, once the inside of the glass tube is degassed, an inert gas is introduced, and the mercury vapor in the glass tube is released by heating. Then, the other electrode holders 3 that have been temporarily stopped are sealed to form the sensor unit 2. Thus, the aforementioned cold cathode fluorescent lamp 1 is obtained by a series of procedures. On the other hand, when a cold cathode lamp 1 is obtained by using a manufacturing apparatus formed of various devices for achieving the various procedures described above, the formation of a coating layer is an important issue. A coating layer forming apparatus (not shown) for forming a coating layer has a heating means for heating the glass tube, a maintaining means for maintaining the glass tube perpendicular or slightly vertical, and a coating liquid for adhering to the coating liquid. A coating device on the inner wall surface of the glass tube, a rotating device for rotating the glass tube around the tube axis, and a drying device for drying the glass tube. According to the coating layer forming apparatus, the coating layer is subjected to a heating procedure for heating the glass tube, a coating procedure for attaching the coating liquid to the glass tube, and drying for drying the coating liquid. The program is formed. Here, the operation sequence, function, and effect in each program will be described. In the heating routine, as shown in Fig. 1(a), the heating device 11 is used to heat the air heated by the heater 12 to the upper end of the glass tube 5 which is maintained in a slightly vertical shape for a predetermined period of time. Air supply to the opening of the glass tube 5 - 14 - 1248107

unit. The temperature of the heater 12 and the air supply time of the air mean that the temperature of the upper portion of the glass tube 5 is set to rise to a predetermined temperature (for example, 80 ° C in the present embodiment). Thereby, the glass tube 5 is heated uniformly in the circumferential direction. Further, the temperature of the glass tube 5 is higher as it is closer to the air supply source side (upper side), and the lower the distance is from the air supply source side (lower side). As shown in Fig. 3, in order to set the temperature of the heater 12 to be equal to the condition of the present embodiment, that is, when the temperature of the heater 12 is set to 300 ° C, the air supply is performed for 45 seconds. The temperature distribution of the glass tube 5 in the case. As is apparent from the figure, the temperature of the glass tube 5 is formed to be higher as the upper portion is formed and lower toward the lower portion. Further, the temperature difference between the upper portion and the lower portion is also 20 ° C or more.

Next, 'in the coating process', as shown in Fig. 1(b), by means of the maintenance device 13, a container in which the coating liquid 14 has been stored is prepared below the glass tube 5 which is maintained in a slightly vertical shape. 15. Further, in the present embodiment, as the solvent of the coating liquid, for example, a butyl acetate as an organic solvent is used. Further, by the coating means 16, air is adsorbed from the upper end of the heated glass tube 5, and the coating liquid 14 is sucked up from the lower end of the glass tube 5. When the coating liquid 14 is filled to the specified height of the glass tube 5, the 'adsorption of air for releasing the air' is set to 1 by the unillustrated & E-turning device. Rotate to rotate the glass tube 5 around its tube axis. Thus, in order to naturally flow down the coating liquid 14, it is discharged from the lower end of the glass tube 5. Thereby, the coating liquid 14 is attached to the inner wall surface of the glass tube 5, and in the drying process, as shown in Fig. 1(C), the rotation of the glass -15-1248107 tube 5 is borrowed. The drying air is blown by the drying device 17 from the opening of the upper end of the glass tube 5 toward the inside of the glass tube 5. Thereby, the coating liquid 14 adhered to the inside of the glass tube 5 is dried to form a coating film layer having a more uniform film thickness. Thus, according to the present embodiment, in the stage before the coating process, the glass tube 5 is set to be heated from the upper end side. Therefore, in the coating process, it is formed such that the glass tube 5 is heated in advance, and drying is started from the point of time when the coating liquid 14 is started to be filled. Further, the glass tube 5 is formed to have a higher temperature as it is above the upper portion, and it is easy to promote drying. Therefore, compared with the prior art, the coating liquid 14 which has adhered to the upper portion is hard to slip. Therefore, unlike the drying process, the coating liquid is caused to slip off before the glass tube is heated, so that the upper film thickness is thinned, so that the thickness of the upper portion of the glass tube 5 can be prevented from being thinned, and the tube can be reached. The difference in film thickness in the axial direction is reduced. Thereby, the difference in brightness of the tube axis direction of the cold cathode fluorescent lamp 1 finally obtained can be remarkably reduced. Furthermore, since the lower portion of the glass tube 5 is lower in temperature than the upper portion, it will not dry as quickly as above. Therefore, it is possible to prevent an unreasonable promotion of drying of the coating liquid 14 to be slid and to increase the thickness of the coating layer. Therefore, regarding the cold-cathode tube 1 finally produced, the film thickness difference of the fluorescent film 4 can be alleviated, and as a result, the difference in brightness in the tube axis direction can be further reduced. Further, the heated air is blown from the opening of the glass tube 5, whereby the glass tube 5 is uniformly heated in the circumferential direction from the inside thereof. Therefore, unlike the case where hot air is blown into the portion -16 - 1248107 from the outer side of the glass tube, it is difficult to cause uneven heating in the circumferential direction of the tube. Therefore, the film thickness of the coating layer in the circumferential direction of the tube can be made uniform. Thus, regarding the cold cathode fluorescent tube 1, the difference in brightness in the circumferential direction can be reduced. Further, it is not limited to the description of the above embodiments, and may be embodied, for example, as follows. (a) In the above embodiment, in the coating procedure, the coating liquid 14 is set to be sucked up from the lower end of the glass tube 5, but the invention is not limited thereto, and injection may be performed from the upper end of the glass tube 5. (b) In the above embodiment, the method of forming the fluorescent film 4 of the cold cathode lamp tube 1 is embodied. However, the case of forming the fluorescent film of another lamp may be embodied. (c) The heating device 11 is formed to blow air, but it is not limited to air, and other gases (for example, inert gases such as nitrogen or argon) or liquids (for example, water or It is higher in volatility than organic solvents such as water). (d) In addition, the air blown by the heating process does not affect the dry air that is blown by the drying process. In this case, the simplification of the device can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an explanatory view for explaining a procedure for forming a coating layer, wherein (a) is a partial sectional view showing a heating procedure, and (b) is a partial section showing a coating procedure. Figure (c) is a partial cross-sectional view showing the drying procedure. Figure 2 is a partial cross-sectional view showing the structure of a cold cathode lamp. • 17-1248107 Figure 3 is a graph showing the temperature distribution of a glass tube that has been heated during the heating process. [Description of representative symbols of main parts] 1 ...cold cathode lamp tube 2..sensor part 3 ...electrode holder 4..fluorescent film 5...glass tube 11...heating device 12.. Heater 13.. Maintenance device 14 . . . coating liquid 15 ... container 16 . . . coating device 1 7 ... drying device

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Claims (1)

1248107 Picking up, patent application scope: 1. A method for forming a coating layer, comprising: a heating program for heating from the inside of the glass tube; a coating procedure 'to maintain the aforementioned heated glass tube to be vertical or In a state of being slightly vertical, 'the coating liquid is adhered to the inner wall surface of the glass tube; and the drying process is to form a coating layer by drying the applied coating liquid. A method for forming a coating layer, comprising: heating a step of heating from an inner side of one end side of a glass tube; and a coating procedure of maintaining the glass tube by setting the one end side to an upper side The coating liquid adheres to the inner wall surface of the glass tube in a vertical or slightly vertical state; a drying process is performed to form a coating layer by drying the adhered coating liquid. 3. The method of forming a coating layer according to claim 2, wherein in the heating process, the hot air is blown from the upper end opening of the glass tube. 4. The coating layer forming method according to claim 2 In order to make the temperature difference between one end and the other end of the heated glass tube to be 20 ° C immediately before the aforementioned coating procedure. 5. The method of forming a coating layer according to claim 3, wherein a temperature difference between one end and the other end of the heated glass tube is formed to be 20 ° C or higher immediately before the coating procedure is performed. 1248107 6- a method for forming a coating layer, comprising: heating a method of maintaining a glass tube perpendicular or slightly vertical, and blowing hot air toward the inside from an opening at an upper end of the glass tube; a process of flowing the coating liquid from the upper end of the heated glass tube. In addition, after the coating liquid is adsorbed from the lower end, the coating liquid is discharged, and the coating liquid is adhered to the inner wall surface of the glass tube; The glass tube to which the coating liquid has been attached is rotated around the tube axis, and the applied coating liquid is dried to form a coating layer by blowing air toward the inside of the glass tube. A method of producing a luminaire, characterized in that the luminescent film is formed by a coating layer forming method according to any one of claims 1 to 6. 8 . A lamp manufacturing apparatus comprising a coating layer forming device for forming a coating layer on an inner wall surface of a glass tube, wherein the coating layer forming device is provided with: a heating device for using glass The inner side of one end side of the tube is subjected to heat of the mouth; the maintaining means is such that the one end side is set to the upper side, and the glass king is kept perpendicular or slightly vertical; the coating device is used after heating The coating liquid is adhered to the inner wall surface of the glass tube; and the drying device is for drying the glass tube. 9. A lamp manufacturing apparatus is provided with a coating layer for forming a coating layer on the inner wall surface of the glass tube. The forming apparatus is characterized in that: -20 - 1248107, the coating layer forming apparatus is provided with: a heating means for blowing and heating hot air toward the inside from one end of the glass tube; and maintaining the apparatus The side is set to the upper side for maintaining the glass tube perpendicular or slightly vertical; the coating device is heated to adhere the coating liquid to the inner wall surface of the glass tube ; Rotating means for causing the glass-based tube axis as a center thereof is rotated; drying means, based air blown toward the inside of said glass tube, so that with the inner glass tube and dried. -twenty one-