JP2002373578A - Forming method of fluorescent face and its forming device, and cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to enlarge an effective display area in a fluorescent face by a transfer method and to form the highly reliable fluorescent face. SOLUTION: In forming the fluorescent face by the transfer method on a panel 80, a transfer film 2 is lowered midway not reaching a panel inner face by a roller 5, and subsequently after having moved the pressure start end part of the roller 5 up to the position corresponding to the brim of the panel inner face, the roller 5 accompanied with the film 2 is pushed down onto the brim of the panel inner face, and the pressing is started against the transfer film 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method and apparatus for forming a phosphor screen with an increased effective display area, higher reliability, improved work efficiency and reduced cost. The present invention relates to a cathode ray tube which has an enlarged effective display area, high reliability, and low cost.

[0002]

2. Description of the Related Art Generally, a slurry method is used for forming a fluorescent screen of a cathode ray tube such as a television receiver or a display for a computer. For example, a fluorescent screen in a color cathode ray tube is formed as follows. First, a photosensitive coating is formed on the inner surface of a panel of a cathode ray tube, that is, a panel having a skirt around the entire periphery. As the photosensitive coating film, for example, PVA (polyvinyl alcohol) -ADC (ammonium dichromate) system or PVP (polyvinyl pyrrolidone) -DAS (4,4'-diazitostilbene 2,
A photosensitive coating such as 2 'ammonium disulfonic acid) can be used. After the photosensitive coating film is dried, it is exposed to ultraviolet light using a color selection mechanism as an optical mask, and is developed by washing with water or the like to form, for example, a stripe-shaped resist layer at a position corresponding to each color. Next, a carbon slurry is applied to the entire surface including the resist layer, dried, and then reversely developed to lift off the carbon layer on the resist layer together with the resist layer, thereby forming a carbon stripe (CS) having a predetermined pattern. Next, a blue phosphor slurry of the first color, for example, is applied, dried, exposed to ultraviolet rays through a color selection mechanism, and developed to form blue phosphor stripes between predetermined carbon stripes (CS). Hereinafter, similarly, a green phosphor stripe and a red phosphor stripe are formed between the other carbon stripes (CS), respectively, to form a target color phosphor screen.

In such a slurry method, it is necessary to rotate a panel of a cathode ray tube when processing a resist layer. At this time, not only power is required, but also a large amount of excess resist solution is scattered around the panel. A great deal of cost and labor is required for the treatment of the resist solution scattered around the panel and the disposal of the excess resist solution. A lot of power is consumed for drying after slurry application. To solve this problem, and for the purpose of simplifying the production of the color cathode ray tube and reducing the power consumption, a method of forming a phosphor screen by a transfer method is known.

The formation of the phosphor screen by the transfer method is performed as follows. A transfer sheet having at least an adhesive layer and a phosphor layer, which is supplied from a supply reel and wound on a take-up reel, is superimposed on the inner surface of the panel of the cathode ray tube (the inner surface on which the carbon stripe is formed), and the transfer roller is placed on the transfer film. Rolling from one end of the inner surface of the panel to the other while heating and pressurizing, and bonding. After the bonding, the transfer roller is removed, the transfer film is peeled off, and the first color, for example, the green phosphor layer is transferred to the entire surface. Thereafter, ultraviolet exposure is performed using the color selection mechanism as an optical mask, developed by washing with water or the like, and dried to form a green phosphor stripe. Hereinafter, a second color, for example, a blue phosphor stripe, and a third color, for example, a red phosphor stripe are sequentially formed by the same transfer method.

[0005]

However, in the conventional method and apparatus for forming a fluorescent screen by the transfer method, since the panel pins for supporting the color selection mechanism protrude from the inner surface of the panel skirt portion, the transfer film is formed on the panel. It is difficult to adhere to the edge of the inner surface, and the effective display area (so-called effective screen) is limited. On the other hand, it is desirable that the transfer pressure can be made uniform over the entire inner surface of the panel including the edge, without causing fogging of the phosphor layer and wrinkles on the phosphor layer at the corners.

An object of the present invention is to provide a method and apparatus for forming a fluorescent screen, which enable an effective display area to be enlarged and a highly reliable fluorescent screen to be formed. An object of the present invention is to provide a cathode ray tube having a large effective display area and high reliability.

[0007]

[Means for Solving the Problems]

In the method of forming a phosphor screen according to the present invention, a transfer film having at least an adhesive layer and a component layer serving as a component of the phosphor screen is lowered by a transfer roller to a position where the transfer film does not reach the inner surface of the panel. After moving the pressing start end to the position corresponding to the edge of the panel inner surface,
The transfer roller and the transfer film are pressed down onto the edge of the inner surface of the panel to start pressing the transfer film.

In the method of forming a fluorescent screen according to the present invention, the transfer film is lowered by the transfer roller to a position not reaching the inner surface of the panel, and then the transfer roller is moved to the edge of the inner surface of the panel. Press down on the edge to start pressing against the transfer film,
The transfer roller can reach the edge of the panel, and the component layer of the phosphor screen can be transferred to the edge of the inner surface of the panel. Therefore, the effective display area can be enlarged by the transfer. Further, the image is transferred at the same transfer pressure over the entire inner surface of the panel. That is, the imbalance in the transfer pressure does not occur,
Uniform transfer of the component layer becomes possible.

[0010] The apparatus for forming a phosphor screen according to the present invention comprises a supply means for supplying a transfer film having at least an adhesive layer and a component layer which is a component of the phosphor screen, and heats and presses the transfer film on a panel. Transfer roller, supply means,
With control means for controlling the transfer roller, the transfer film is lowered by the transfer roller halfway to the inner surface of the panel, and then the pressing start end of the transfer roller is moved to a position corresponding to the edge of the inner surface of the panel, The transfer roller and the transfer film are controlled so as to be pressed down onto the edge of the inner surface of the panel to start pressing the transfer film.

In the phosphor screen forming apparatus of the present invention, the transfer roller temporarily stops at a position where the transfer roller and the transfer film do not reach the panel inner surface, moves to the edge of the panel inner surface, and then moves together with the transfer film to the end of the panel inner surface. Since the control is performed so as to start pressing the transfer film by pressing down on the edge, it is possible to transfer the component layer of the phosphor screen to the edge of the inner surface of the panel. The transfer film can be transferred at the same transfer pressure over the front surface of the inner surface of the panel, and as a result, a highly reliable phosphor screen can be formed. Therefore, the effective display area can be enlarged by the transfer.

A cathode ray tube according to the present invention has a phosphor screen formed as described above.

In the cathode ray tube according to the present invention, the constituent layer of the fluorescent screen is formed up to the edge of the inner surface of the panel, and the fluorescent screen formed by using a transfer film and pressing the transfer roller under the same conditions over the entire inner surface of the panel. As a result, the effective display area can be enlarged, and the reliability of the phosphor screen increases.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the method and apparatus for forming a phosphor screen and the cathode ray tube of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 3 show a schematic configuration of a phosphor screen forming apparatus according to the present embodiment, that is, a so-called transfer apparatus 1. FIG.
This example is a case where the present invention is applied to transfer of a phosphor screen to a panel of a cathode ray tube. The transfer device 1 according to the present embodiment includes a supply reel 3 for supplying a transfer film 2 having at least a component layer serving as a component of a fluorescent screen and an adhesive layer, and a transfer film 2 after transfer, which will be described later. Take-up reel 4 for winding the upper film base 31, a transfer roller, a so-called thermal transfer roller 5, pressing means 6 for pressing the thermal transfer roller 5, and moving the thermal transfer roller 5 at a predetermined speed along the transfer direction. Moving means 7 for moving and thermal transfer roller 5
And a panel mounting table 9 on which a panel 80 of a cathode ray tube is mounted.

Here, the panel 80 of the cathode ray tube is formed in a shape having a so-called skirt portion 80s which rises around the front surface on which the fluorescent screen is formed, and a color selection mechanism is provided inside the skirt portion 80s on the four sides. Support pins (so-called panel pins) 82 are provided for supporting the panel. The color selection mechanism supports the panel 80 at four points. The panel 80 in the present embodiment is a panel for a horizontally long and flat cathode ray tube.

The pressing means 6 presses the thermal transfer roller 5 against the inner surface of the panel 80 via the transfer film 2. A configuration in which the drive is controlled so that the depressed position can be changed can be employed. The pressing means 6 can be composed of, for example, an air cylinder. Pressing means such as air cylinder 6
Is fixed to a support (not shown), and the tip of the cylinder rod 6 a is fixed to the center of a fixed substrate 10 supporting the heating means 8 and the thermal transfer roller 5.

The heating means 8 is for heating the thermal transfer roller 5 to a predetermined temperature. The heating means 8 of this embodiment is formed in a semi-cylindrical shape above the thermal transfer roller 5 along the longitudinal direction of the roller. In this case, the rod-shaped heater 12 is built in the heater cover 13. The thermal transfer roller 5 is heated by the heating means 8 and is controlled to a required constant temperature, that is, a temperature at which thermal transfer is possible, for example, about 120 ° C. When the thermal transfer roller 5 is heated, the thermal transfer roller 5
Is rotated so that the entire roller is uniformly heated to the control temperature without unevenness. The heating means 8, that is, the heater is not limited to the indirect heating type as in the present embodiment, but may be a direct heating type for directly heating the thermal transfer roller 5 from the center.

The panel mounting table 9 is disposed on the support base 11 so as to be movable between a panel input position and a position immediately below the thermal transfer roller 5. The panel mounting table 9 is configured such that the panel 80 can be fixed, for example, by vacuum suction, with the panel 80 mounted thereon such that the panel inner surface faces upward. The panel mounting table 9 may be at room temperature, or a heater may be provided below the mounting table 9 to maintain the temperature of the panel 80 at room temperature of 40 to 45 ° C. The panel mounting table 9 can be configured so that the panel 80 can be selectively inclined to one or the other with respect to the transfer direction at the time of transfer.

The movable means 7 is controlled by a control means as necessary so that the thermal transfer roller 5 can be moved only in the panel 80 at the time of transfer, or can be made to reciprocate one time, and further can be reciprocated a plurality of times. It is configured so that it can be set.

The thermal transfer roller 5 is rotatably mounted about the horizontal shaft 15 and has a width capable of being inserted into the panel 80, that is, a width inside the panel 80 when heated to a required temperature (in this example, a screen vertical). The width of the thermal transfer roller 5 is approximately the same as or slightly shorter than the width, and the thermal transfer roller 5 can be positioned at the transfer start end while avoiding the panel pins 82 provided inside the skirt portion 80s of the panel 80. As described above, a notch 16 is formed in a part of the outer surface over the entire length in the longitudinal direction.
Is configured. The thermal transfer roller 5 has a hardness of 70 to 9
It can be formed by an elastic roller of about 0 °, for example, about 80 °, for example, a silicone roller made of heat-resistant silicone rubber or the like.

The thermal transfer roller 5 is formed such that the transfer film can be heated and pressed to the inner surface of the panel 80 from one end to the other end by one rotation from one end to the other end of the cutout portion 16.

Further, in the thermal transfer roller 5, as shown in FIG. 8B, the peripheral edges of both ends in the axial direction of the thermal transfer roller 5 are rounded at the upper and lower edges of the inner surface of the horizontally long panel 80 (ie, the inner surface of the panel and the skirt portion 80s). Are formed in the same round shape (= R ₁ ) as the curved surface [radius of curvature R ₁ ] of the boundary portion of FIG. 1 (see FIG. 1), and as shown in FIG. It is formed in the same round shape (= R ₂ ) as the rounded portion at the left and right end sides of the inner surface (that is, the curved surface [radius of curvature R ₂ ] at the boundary between the panel inner surface and the skirt portion 80 s, see FIG. 1). Notch 16 of thermal transfer roller 5
Corner portions of, as shown in FIG. 8A, panel 80 for a confluence portion between the curved portion (i.e. R ₁ and R ₂ of the corner portion of the inner surface, the curved surface [radius of curvature R _3] which approximates a spherical surface,
It is formed in the same round shape (= R ₃ ) as that of FIG.

The rotational position of the thermal transfer roller 5 at the start of transfer,
That is, a detecting device 18 for detecting the rotational position on one end side of the notch 16 is provided. The detecting device 18 includes a detecting plate 19
And a photoelectric sensor 20. In this example, the detection plate 19 is provided coaxially with the thermal transfer roller 5 so as to rotate in conjunction with the rotation of the thermal transfer roller 5. That is, one end of the drive shaft 15 of the thermal transfer roller 5 is rotated integrally with the thermal transfer roller 5, and the position of the thermal transfer roller 5 (the notch 16 which reaches the inner surface of the panel while avoiding a panel pin which will be described later).
(A position at which one end of the panel can be rolled to the edge of the inner surface of the panel) is attached. The detection plate 19 has a disk shape, and has a linear slit 21 extending radially at one location in the circumferential direction.
The angle between the slit 21 and one edge 16a of the notch 16 is θ ₁ (for example, FIG. 11A).
(Refer to FIG. 3). A pair of the light emitting element 22 and the light receiving element 23 are sandwiched by the detection plate 19.
(See FIGS. 1 and 2). In this case, when the slit 21 of the detection plate 19 comes to the vertical position, the light from the light emitting element 22
Through the light receiving element 23, and it is detected that the thermal transfer roller 5 has reached the rotational position at which the transfer is started. A motor 25 for rotating and driving the thermal transfer roller 5 is provided at the other end of the drive shaft 15 (see FIG. 2).

The take-up reel 4, the thermal transfer roller 5, the movable means 7, the panel mounting table 9 and the like are rotated by a drive source such as a motor and the like, and their positions are detected by a rotation sensor and the apparatus is controlled by a control means such as a microcomputer. It is configured to be controlled overall. Further, the transfer device 1 is provided with a control panel (not shown) for inputting initial settings to control means.

As shown in FIG. 3, during the transfer of the transfer film 2 wound from the supply reel 3 to the take-up reel 4 via the guide roller 41, the panel 8 during transfer is transferred.
A pair of L-shaped transfer film holding members 42 for holding the transfer film 2 from above and bringing the transfer film 2 to an intermediate position in the panel 80 at positions corresponding to both ends of the transfer film 2.
And 43 are provided. The one holding member 42 is arranged at a fixed position and is rotatable at one end, and is configured to hold the transfer film 2 by the skirt portion of the panel when turned downward. The other pressing member 43 is arranged so as to be able to move up and down, and is configured to press the transfer film 2 with the skirt portion of the panel when moving downward. Further, a second take-up reel 44 is provided to take up the lower film base peeled off to expose an adhesive layer described later on the transfer film 2 supplied from the supply reel 3 at the time of transfer.

In the present embodiment, the heat transfer roller 5 which descends together with the transfer film 2, particularly at the start of transfer, is
After temporarily stopping in the middle of the panel, and then moving the pressing start end of the thermal transfer roller 5, that is, the edge of the notch 16 to a position corresponding to the edge of the panel inner surface, the edge of the panel inner surface together with the transfer film 2. , And the thermal transfer roller 5 is driven and controlled so as to start pressing against the transfer film 2.

Transfer film 2 used in this embodiment
18 is shown in FIG. The transfer film 2 includes an upper film base (for example, polyethylene terephthalate [PET] base) 31, a cushion layer 32,
Upper release layer 33, a component layer serving as a component of the phosphor screen,
For example, a phosphor layer 34 having photosensitivity, an adhesive layer 35 having photosensitivity, a lower release layer 36 and a lower film base (P
(ET base) 37 are laminated. As a specific example of the thickness of each layer, upper and lower film bases 31, 3
7, about 50 μm, cushion layer 32 about 40 μm,
The thickness of the phosphor layer 34 is about 3 μm. When the transfer film 2 is used, the lower film base 37
Is peeled off to expose the adhesive layer 35, and the transfer film 2 is adhered to the inner surface of the panel via the adhesive layer 35. After bonding, the upper release layer 33 is peeled off from the cushion layer 32 and the upper film base 31, leaving the phosphor layer 34 on the inner surface of the panel. In the transfer film 2, after the phosphor layer 34 is thermocompression-bonded to the inner surface of the panel via the adhesive layer 35, the adhesive layer 35 and the phosphor layer 34 are cut off from the boundary between the bonded portion and the non-bonded portion. In addition, the adhesive strength of the upper release layer 33 is set to be larger than the adhesive strength of the adhesive layer 35 to the panel.

Next, the transfer method will be described together with the operation of the transfer device 1 described above. First, before the start of the transfer, the thermal transfer roller 5 rotates with its temperature controlled. That is, the thermal transfer roller 5 rotates while being heated and adjusted to a desired temperature by the heating means 8. A panel 80 on which a fluorescent screen is to be formed is conveyed and set on the panel mounting table 9 with its inner surface facing upward. The panel mounting table 9 moves to a predetermined position immediately below the transfer roller 5. Upon receiving a signal indicating that the panel 80 has moved to the predetermined position, the preparation for starting the apparatus 1 is completed.

Next, the basic operation will be described with reference to FIGS.
Is performed as shown in FIG. That is, as shown in FIG. 3, the transfer roller 5 is waiting at the transfer start position. The transfer film 2 is fed out from the supply reel 3, and the lower film base 37 is wound up by the second take-up reel 44 on the way, so that the adhesive layer 35 is exposed. Next, the detection plate 1
The position of the slit 21 is detected by the detecting means 20, and it is sensed that the thermal transfer roller 5 has reached a predetermined rotational position. At this time, one edge 16a of the notch 16 of the thermal transfer roller 5 corresponds to a position where it does not hit the panel pin 82 (more specifically, the pressing member 43 in FIG. 4). When the thermal transfer roller 5 reaches the predetermined rotation position, the heating means 8 is turned off and the rotation of the thermal transfer roller 5 stops.
In this state, the thermal transfer roller 5 is free to rotate.

Next, as shown in FIG. 4, the pair of pressing members 42 and 43 are operated to press the transfer film 2 into the panel 80 while pressing the transfer film 2 from above.
In steps 2 and 43, the transfer film 2 is pressed. Thereafter, the cylinder 6, which is a pressing means, is driven to lower the thermal transfer roller 5, and the transfer film 2 is further pushed into the inner surface of the panel 80.

Next, as shown in FIG. 5, the moving means 7 is driven to move the thermal transfer roller 5 to the inner surface of the panel 80 from one end to the other end. At this time, the thermal transfer roller 5
Since the panel 80 is in contact with the inner surface of the panel 80 via the transfer film 2, the panel 80 moves while rotating in the horizontal direction (so-called rolling). The transfer film 2 is heated and pressurized by the thermal transfer roller 5 and adheres to the inner surface of the panel via the adhesive layer 35. After the transfer film 2 for the area of the panel inner surface is adhered, the thermal transfer roller 5 and the pressing members 42, 4
3 returns to the standby position of FIG. At the same time, when the transfer film 2 is taken up by the first take-up reel 4, the upper film base 31 and the cushion layer 32 are peeled off together with the peeling layer 33 from the transfer film 2 in the portion adhered to the panel, and heated and heated. The portions of the phosphor layer 34 and the adhesive layer 35 that are not pressed are cut off from the adhesive portion. As a result, only the phosphor layer 34 remains on the inner surface of the panel 80, and the phosphor layer 34
Is completed.

In order to widen the effective display area of the cathode ray tube as much as possible, the transfer film 2 needs to be widely adhered to the inner surface of the panel 80 so as to straddle the round portion 83 bordering the skirt portion 80s. . That is, the transfer film 2
Since it is difficult to determine the position at the time of transfer, as shown in FIG. 19, the fluorescent screen formed on the inner surface of the panel 80, which is a so-called effective display area 85, is wider by a predetermined dimension d, for example, is wider by about 2 mm around the periphery. Must be formed.
In order to make the effective display area 83 closer to the peripheral edge of the panel, the transfer film 2 is bonded so as to straddle the peripheral edge of the panel and the round portion 83 of the corner portion.

At the start of the transfer of the transfer film 2, there are two methods for bonding the end of the transfer film 2 to one end of the inner surface of the panel 80. 9 and 10 show one such method. In this method, as shown in FIG. 9, the thermal transfer roller 5 is vertically moved while pressing down the transfer film 2 while avoiding the pressing member 43. When the thermal transfer roller 5 reaches the inner surface of the panel 80, as shown in FIG. 10, the moving means 7 is driven to temporarily roll the thermal transfer roller 5 in the reverse direction, that is, to the right in the figure, and dive below the panel pin 82. The thermal transfer film 2 is heated and pressed so as to partially extend over the rounded portion 83 at the right edge of the panel. Next, as shown in FIG. 5 described above, the heat transfer roller 5 is rolled to the left in the figure, and the transfer film 2 is similarly heated and pressed so as to partially straddle the round portion 83 at the left edge of the panel. Glue. After the transfer film 2 has been bonded, the heat transfer roller 5 is moved in the opposite direction from the start of the transfer, that is, slightly returned to the right from the left edge, and then raised to return to the standby position.

9 and 10, the right edge of the panel is heated and pressed by the thermal transfer roller 5 twice. For this reason, the transfer pressure balance changes over the entire surface of the panel (therefore, the balance of the adhesiveness of the phosphor layer to the panel surface changes), and in extreme cases, fog (color mixing) of the phosphor layer easily occurs. That is, the balance of the transfer pressure affects the exposure and development of the phosphor layer after transfer, which will be described later. Part of the body remains, which causes fog.

FIGS. 11 to 13 show another method, that is, the method according to the present embodiment. In this method, as shown in FIG. 11, the thermal transfer roller 5 is temporarily stopped before reaching the inner surface of the panel while pushing down the transfer film 2 while avoiding the pressing member 43. Next, as shown in FIG. 12, the moving means 7 is driven to move the thermal transfer roller 5 in the opposite direction, that is, to the right in the figure, so as to dive below the panel pin 82, corresponding to the round portion 83 at the right edge of the panel. Bring to position. Next, as shown in FIG. 13, the thermal transfer roller 5 is lowered vertically so that one end edge 16 a of the notch 16 is positioned over the transfer film 2 so as to straddle a part of the round portion 83 at the right edge of the panel. Touch Then, the moving means 7 is driven, and from this state, the thermal transfer roller 5 is rolled to the rounded portion 83 at the left end edge, and the transfer film 2 is heated and pressed. After the bonding of the transfer film 2 is completed, there are two types of operations of the thermal transfer roller 5. One method is the reverse of the operation at the start of the transfer, that is, after reaching the left edge, slightly raises the thermal transfer roller 5 and stops halfway, and then moves the thermal transfer roller 5 rightward and separates from the pressing member 42. Then, raise it again and return it to the standby position. The other method is the same operation as that described with reference to FIGS. 9 and 10. After reaching the left end edge, the thermal transfer roller 5 is slightly rolled rightward and raised at a position away from the pressing member 42 to raise the standby position. Return to

According to the method in which the thermal transfer roller 5 is temporarily stopped in the panel 80, moved to the edge side, and then lowered to the panel inner surface, the thermal transfer roller 5 reaches the edge portion of the panel inner surface, and the edge of the panel inner surface. The component layer of the phosphor screen can be transferred to the fluorescent screen. In addition, since the transfer can be performed at the same transfer pressure over the entire inner surface of the panel including the edge, the transfer pressure balance is not disturbed as described above, and the component layers can be uniformly transferred. Therefore, in the transfer of the phosphor layer, it is possible to suppress the occurrence of fogging of the phosphor layer and wrinkles at the edges and corners of the phosphor layer. Since the component layer can be transferred to the edge, the effective display area can be further enlarged.

On the other hand, in the thermal transfer roller 5, both end edges in the axial direction have the same round shape (= radius of curvature R ₁ ) as the upper and lower end round portions of the inner surface of the panel.
Has the same round shape (= radius of curvature R ₂ ) as the right and left edges of the panel inner surface, and the corner of the notch 16 has the same spherical shape as the corner of the panel inner surface (= radius of curvature R ₃ ). Therefore, the adhesion of the transfer film 2 to the periphery of the panel inner surface is improved.

When the transfer film is adhered at the rounded portions 83 at the left and right edges of the inner surface of the panel 80,
The panel 80 can be selectively inclined and bonded to one or the other with respect to the transfer direction. For example, FIG.
As shown in B (an enlarged view of a main part), when bonding one end edge of the transfer film 2 to the rounded portion 83 at the right end edge at the start of transfer, the panel 80 is inclined so that the left end side of the panel is lifted. After the adhesion of the transfer film 2 to the right edge 83 is completed, the panel 80 is returned to the horizontal state, and the thermal transfer roller 5 is moved to the left edge to adhere the transfer film 2 to the inner surface of the panel. The left edge 83
15A and 15B (enlarged view of a main part), the panel 80 is tilted so that the right end is lifted, and the transfer film 2 is bonded to the rounded portion 83 at the left end as shown in FIGS. Eggplant As described above, when the transfer film 2 is transferred to the rounded portion 83 of the panel edge, the surface of the rounded portion 83 is nearly horizontal by tilting with the panel end on the side to be transferred downward. Thus, the bonding by the thermal transfer roller 5 is performed stably.

In the present embodiment, although not shown, for example, the phosphor layer is transferred to the end of the panel in contact with the skirt portion 80s, and the carbon layer, which is the light absorbing layer, is transferred from the end of the panel to the skirt portion 80s. The image is transferred to the round portion 83.

When the thermal transfer roller 5 rolls along the inner surface of the panel, it is preferable to reciprocate the thermal transfer roller 5 on the inner surface of the panel 80 as shown in FIG. In this example, one reciprocating rolling is performed. It is also possible to make a plurality of rotations if necessary. The reciprocating rolling of the thermal transfer roller 5 is suitable for application to transfer of a phosphor layer after forming a carbon stripe as a light absorbing layer when forming a color phosphor screen. This is particularly effective in transferring the phosphor layers of the second and subsequent colors.

FIG. 7 shows an example in which a carbon stripe 51 as a light absorbing layer is formed on the inner surface of a panel 80, and a first color, for example, blue (B) phosphor layer stripe 52B is provided in a gap between the required carbon stripes 51. After forming, 2
This is a case where the transfer film 2R having the phosphor layer 34R of a color, for example, red (R) is adhered by the thermal transfer roller 5.
When the thermal transfer roller 5 rolls from the right edge to the left edge with respect to the transfer film 2R, that is, in the “forward rolling”, as shown in FIG.
Is sufficiently adhered to the step portion on the advancing side of the thermal transfer roller 5, but not sufficiently adhered to the step portion shadowed by the blue phosphor stripe 52B, and a gap 90 is generated. Next, as shown in FIG. 7B, when the thermal transfer roller 5 rolls from the left edge to the right edge, that is, in the “reverse rolling”, the gap that is shaded by the forward rolling and is not bonded. Ninety portions are sufficiently bonded, and the entire surface is uniformly bonded.

When the thermal transfer roller 5 is reciprocated on the inner surface of the panel 80, the roller pressing force can be made constant. Alternatively, the roller pressing force can be made different between going and returning. When the thermal transfer roller 5 is reciprocated on the inner surface of the panel 80, the moving speed of the thermal transfer roller 5 can be made constant in the reciprocation. Alternatively, the traveling speed can be made different between going and returning. The lower the moving speed of the thermal transfer roller 5 and the higher the roller pressing force, the higher the adhesive strength of the transfer film 2 to the panel 80. Therefore,
If the pressing force of the thermal transfer roller 5 and the moving speed are controlled to control the adhesive force of the transfer film 2, more preferable transfer can be performed.

As described above, the thermal transfer roller 5 is
The adhesive layer 35 of the transfer film 2 can be inserted evenly between stripes such as between carbon stripes and phosphor stripes already formed by reciprocating within, and the intended transfer is performed favorably. The reliability of the phosphor screen can be increased.

Next, the formation of the color phosphor screen including the above-described transfer step will be described with reference to FIGS.
First, as shown in FIG. 16A, a light absorbing layer, for example, a carbon stripe is formed on the inner surface of the panel 80. This carbon stripe 51 is formed by a usual slurry method,
Alternatively, it can be formed by the above-described transfer method.

Next, as shown in FIG.
Of the first color, for example, the blue phosphor layer 34B and the adhesive layer 3
The blue phosphor layer 34B is transferred by a transfer method using a transfer film 2B having the same configuration as that shown in FIG.
In the transfer using the thermal transfer roller 5, for example, 120
1.3 kg / cm ² while heating to 100 ° C. (100
kg), the transfer film 2 is pressure-bonded onto the panel. The blue phosphor layer 34B is irradiated with light (for example, ultraviolet light) L using the color selection mechanism 76 as an optical mask to perform exposure to blue. In this exposure processing, both the blue phosphor layer 34 and the adhesive layer 35 are exposed.

Next, as shown in FIG. 16C, a blue phosphor stripe 52B is formed between predetermined carbon stripes by water development and drying.

Next, as shown in FIG.
Of the second color, for example, the red phosphor layer 34R and the adhesive layer 3
The red phosphor layer 34R is transferred by a transfer method using a transfer film 2R having the same configuration as that shown in FIG.
The red phosphor layer 34R is irradiated with light (for example, ultraviolet light) L using the color selection mechanism 76 as an optical mask to perform red exposure.

Next, as shown in FIG. 16E, water development processing and drying processing are performed to form red phosphor stripes 52R between predetermined carbon stripes.

Next, as shown in FIG.
Of the third color, for example, the green phosphor layer 34G and the adhesive layer 3
The green phosphor layer 34G is transferred by a transfer method using a transfer film 2G having the same configuration as that shown in FIG.
The green phosphor layer 34G is irradiated with light (for example, ultraviolet light) L using the color selection mechanism 76 as an optical mask to perform exposure to green.

Next, as shown in FIG. 17G, a green phosphor stripe 52G is formed between predetermined carbon stripes by water development and drying.

Next, as shown in FIG. 17H, an intermediate film (not shown) is applied, and a metal back layer 53 of, for example, aluminum (Al) is formed on the entire surface. If a transfer film having at least an Al layer and an adhesive layer is used, the metal back layer 53 can be formed by transfer. Thus, the desired color phosphor screen 55 is obtained. By using the transfer method according to the present embodiment, it is possible to form a highly reliable phosphor screen having a large effective display area.

FIG. 20 shows an embodiment of a color cathode ray tube according to the present invention. The color cathode ray tube 77 according to the present embodiment includes a panel 80 of a cathode ray tube (glass tube) 78.
Is formed on the inner surface by the above-described phosphor screen forming method according to the present invention, and a color phosphor screen 55 composed of red (R), green (G), and blue (B) phosphor layers is formed. Then, a color selection mechanism 76 is arranged, and an in-line type electron gun 75 is arranged in the neck portion 79, for example. On the outside of the tube 78, the electron beam B _R from the electron gun 75,
The B _G and B _B horizontally, deflection yoke 74 for deflecting in the vertical direction is arranged. In the color cathode ray tube 77, the electron gun 83 of red (R), green (G), and blue (B) cathode K corresponding to [K _R, K _G, K _B] electron beams corresponding to the respective colors emitted from B [B _R, B _G, B _B] are converged by the main electron lens formed of a plurality of grid electrodes are focused on the phosphor screen 55, is and convergence with red, green, irradiating each color phosphor layers of blue Is done. The electron beams B _R , B _G , and B _B are deflected in the horizontal and vertical directions by the deflection yoke 74 to display a required color image.

According to the color cathode ray tube according to the present embodiment, since the phosphor screen 55 formed by the above-described transfer method of the present invention is provided, the reliability of the phosphor screen 55 is improved and the effective display area is enlarged. A color cathode ray tube capable of displaying a larger screen can be provided.

As described above, according to the present embodiment,
When transferring the transfer film onto the panel by the transfer roller, when the transfer is performed by reciprocating the transfer roller at least one time on the panel, the speed of the transfer roller can be increased, and the efficiency of the transfer process and, therefore, the work efficiency Can be improved. Further, by performing the transfer by reciprocating the transfer, the adhesive layer of the transfer film can be evenly transferred, for example, between the adjacent light absorbing layers or adjacent phosphor layers without unevenness, and uniform transfer can be performed. It is possible to form a fluorescent screen having a high density. In particular, when the constituent layers of the transfer film are phosphor layers corresponding to each color, it is effective in transferring the transfer films of the second and subsequent colors. The cost of forming the phosphor screen can be reduced. When the transfer roller is reciprocated at least once during transfer, the transfer speed can be increased, and transfer efficiency can be improved. The adhesive layer of the transfer film can be uniformly adhered over the entire surface, and transfer reliability can be improved. Since the transfer method is used to form the phosphor screen, the phosphor screen can be formed at lower cost and with higher reliability than the slurry method.

When transferring the transfer film onto the panel by the transfer roller, the transfer roller descending with the transfer film is temporarily stopped in the panel, moved to the edge side, and then lowered to the panel inner surface to start pressing on the transfer film. In this case, the component layer of the phosphor screen can be transferred well to the edge including the corner portion of the inner surface of the panel, and the effective display area can be enlarged by the transfer. Pressing starts from the edge of the inner surface of the panel and is transferred at the same transfer pressure over the entire inner surface of the panel, so that fog of the phosphor layer and wrinkles of the phosphor layer at the corners can be eliminated, and highly reliable fluorescent light can be obtained. A surface can be formed. It is also possible to improve the efficiency of the transfer process and hence the workability.

When the transfer film 2 is adhered to the edge portion including the corner portion of the inner surface of the panel, when the panel 80 is inclined, the transfer film 2 can be adhered to the edge portion of the panel without wrinkles, and the reliability is improved. A high phosphor screen can be formed. When the thermal transfer roller 5 uses a thermal transfer roller in which the portion corresponding to the peripheral portion and the corner portion of the panel inner surface is formed in the same round shape as the round portion, the transfer film 2 to the edge portion including the corner portion of the panel inner surface is used. Can be bonded without wrinkles to the rounded portion of the edge, and a highly reliable fluorescent screen can be formed. In particular, together with these, it is possible to form a phosphor screen having high reliability and a large effective display area. It is possible to improve the efficiency of the transfer process, and thus improve the workability.

When a fluorescent screen is formed by using the above-described transfer method, a cathode ray tube having high reliability and a large effective display area can be provided. The cost of the cathode ray tube can be reduced.

Note that the above-described transfer method of the present invention can be applied to transfer of all components constituting the fluorescent screen. Accordingly, the transfer film 2 has a so-called component layer serving as a component of the phosphor screen, which includes a monochromatic phosphor layer facing each color, and red, green, and blue phosphor layers (for example, phosphor stripes). A transfer film formed of a full-color phosphor layer, a light absorbing layer (for example, a carbon layer serving as a carbon stripe), or a metal layer such as aluminum serving as a metal back layer can be used.

In the above example, the method of forming a phosphor screen of the present invention
It was applied to the production of the fluorescent screen of a color cathode ray tube.
For example, the present invention can be applied to a monochromatic cathode ray tube for a projector, a plasma display panel (PDP), a liquid crystal display (LCD), a field emission display (FED), and other display devices using other phosphors.

[0061]

According to the method of forming a phosphor screen according to the present invention, when the transfer film is transferred onto the panel by the transfer roller, the transfer roller descending together with the transfer film is temporarily stopped in the panel and moved toward the edge. After moving, it is lowered to the panel inner surface and starts pressing against the transfer film,
The constituent layer of the fluorescent screen can be transferred to the edge of the inner surface of the panel, so that the effective display area can be enlarged by the transfer. In addition, pressing starts from the edge of the panel inner surface and is transferred at the same transfer pressure over the entire panel inner surface, so that fog of the phosphor layer and wrinkles of the phosphor layer at the corners can be eliminated, and reliability is improved. A high phosphor screen can be formed.
It is also possible to improve the efficiency of the transfer process and hence the workability. Since the transfer method is used to form the phosphor screen, the phosphor screen can be formed at lower cost and with higher reliability than the slurry method.

According to the phosphor screen forming apparatus of the present invention,
At the start of transfer, the transfer roller that moves down with the transfer film is temporarily stopped in the panel, moved to the edge side, and then lowered to the panel inner surface to start pressing on the transfer film, so that transfer to the edge of the panel inner surface is performed. The film can be adhered, and the effective display area can be enlarged by transfer. Further, the transfer film can be adhered with a uniform transfer pressure over the entire inner surface of the panel including the edge, and the fog of the phosphor layer and the wrinkles of the phosphor layer at the corners can be eliminated, thereby improving the transfer reliability. The cost of forming the phosphor screen can be reduced.

According to the cathode ray tube of the present invention, since the fluorescent screen formed by using the above transfer method is enlarged, a cathode ray tube having a high reliability and a large effective display area can be provided. The cost of the cathode ray tube can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an embodiment of a transfer device according to the present invention.

FIG. 2 is a sectional view of a main part of FIG.

FIG. 3 is an operation diagram (1) for explaining a basic operation of the transfer device according to the present invention;

FIG. 4 is an operation diagram (part 2) for describing a basic operation of the transfer device according to the present invention.

FIG. 5 is an operation diagram (part 3) for explaining a basic operation of the transfer device according to the present invention.

FIG. 6 is an operation explanatory view showing one embodiment of a transfer method according to the present invention.

FIGS. 7A and 7B are cross-sectional views illustrating a bonded state of a transfer film by the transfer method of FIG.

FIGS. 8A and 8B are configuration diagrams illustrating a shape of a transfer roller according to the present invention.

FIG. 9 is an explanatory view (part 1) of a main part showing one operation example of a transfer roller at the start of transfer.

FIG. 10 is an explanatory diagram (part 2) of a main part showing one operation example of the transfer roller at the start of transfer.

FIG. 11 is an explanatory diagram (part 1) of a main part showing one embodiment of the operation of the transfer roller at the start of transfer according to the present invention.

FIG. 12 is an explanatory view (part 2) of a main part showing one embodiment of the operation of the transfer roller at the start of transfer according to the present invention.

FIG. 13 is an explanatory view (part 3) of a main part showing one embodiment of the operation of the transfer roller at the start of transfer according to the present invention.

FIG. 14A is a cross-sectional view illustrating an example of a transfer method when a transfer film is bonded to a rounded portion at one edge of the panel inner surface according to the present invention. B It is an enlarged view of the principal part of Drawing A.

FIG. 15A is a cross-sectional view illustrating an example of a transfer method when a transfer film is adhered to a rounded portion at the other edge of the panel inner surface according to the present invention. B It is an enlarged view of the principal part of Drawing A.

16A to 16E are process diagrams (part 1) illustrating an embodiment of a method for forming a phosphor screen according to the present invention.

17A to 17H are process diagrams (No. 2) showing an embodiment of the method of forming a phosphor screen according to the present invention.

FIG. 18 is a cross-sectional view showing one embodiment of a transfer film applied to the present invention.

FIG. 19 is a plan view showing a relationship between an effective display area and a transfer area of a transfer film.

FIG. 20 is a configuration diagram showing one embodiment of a cathode ray tube according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Transfer device, 2, 2R ... Transfer film, 3
... supply reel, 4 ... take-up reel, 5 ... transfer roller, 6 ... pressing means, 7 ... moving means, 8.
..Heating means, 9 ... Panel mounting table, 19 ... Detection plate, 20 ... Photoelectric sensor, 31, 37 ... Film base, 32 ... Cushion layer, 33, 36 ... Peel off Layer, 34, 34R: phosphor layer, 35: adhesive layer, 42, 43: pressing member, 44: second take-up reel, 51: carbon stripe, 52 [5
2 _R , 52 _G , 52 _B ] ... phosphor stripe, 80
... panel, 83 ... round part, 90 ... gap.

Claims (4)

[Claims] 1. A method for forming a phosphor screen on a panel using a transfer film having at least an adhesive layer and a component layer serving as a component of the phosphor screen, wherein the transfer film is transferred. The roller is lowered to a position not reaching the inner surface of the panel, and then the pressing start end of the transfer roller is moved to a position corresponding to the edge of the inner surface of the panel. A method of forming a phosphor screen, wherein the phosphor film is pressed down on an edge to start pressing the transfer film. 2. The phosphor screen according to claim 1, wherein the constituent layer is a phosphor layer corresponding to each color, a phosphor layer integrally having each color, a light absorbing layer or a metal back layer. Forming method. 3. An apparatus for forming a phosphor screen on a panel, comprising: a supply means for supplying a transfer film having at least an adhesive layer and a component layer serving as a component of the phosphor screen; A transfer roller for heating and pressurizing the transfer film; and a control unit for controlling the supply roller and the transfer roller. The transfer roller is lowered to a point where the transfer roller does not reach the inner surface of the panel, and then the transfer roller After moving the pressing start end portion to a position corresponding to the edge of the panel inner surface, the transfer roller is pressed down together with the transfer film onto the edge of the panel inner surface to start pressing on the transfer film. An apparatus for forming a phosphor screen, which is controlled. 4. A cathode ray tube having a phosphor screen formed on a panel, wherein a component layer serving as a component of the phosphor screen is formed up to an edge of an inner surface of the panel and transferred using a transfer film. A cathode ray tube, wherein the pressing condition of the roller is the same over the entire inner surface of the panel.