JPS5920466B2 - phosphorescent tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a phosphorescent tape, and is particularly suitable for a thermally transferable phosphorescent tape.

First, the outline of the phosphorescent tape will be explained with reference to FIG.

That is, the phosphorescent tape is a tape having a thickness of about 10 microns, for example, using polyethylene terephthalate 1 as a base material, and a phosphor 2 coated on this base material via a binder 3. Here, the binder 3 is mainly made of wax, for example, in order to ensure sufficient bonding force between the base material, the phosphor, and the phosphor.
Dehydrated castor oil, trichlene mixture (application solution) is used.

(However, trichlene is dissipated during the drying process during the manufacturing process.) Such phosphorescent tapes have traditionally been used for transferring coatings, etc., to clearly transfer the transferred material to, for example, coding paper, and to protect the transferred fluorescent material. Sufficient light emission by excitation of ultraviolet light to the light body layer is required, for example. In order to meet the above requirements, it is necessary that the phosphor layer formed on the substrate be uniform, and particularly that the granularity of the phosphor in the coating layer be uniform.

However, conventionally used phosphorescent tapes have poor granularity in the coating layer, which may result in unclear boundaries of transfer marks, incomplete transfer, or uneven and insufficient luminescence of transfer marks. There were some drawbacks such as getting hot. The present inventor focused on the fact that the main cause of these problems is the granularity of the phosphor used as a material, especially non-uniform particle size, and improved the conventional drawbacks to achieve clear transfer and good light emission. He invented a phosphorescent tape that produced the following.

That is, the present invention provides a phosphorescent tape comprising a coating layer consisting of a binder and a phosphor on the surface of a tape-like base material, in which the phosphor has a particle size of 3 to 9 μm.
The phosphorescent tape is characterized in that it contains 0 weight percent or more.

This unique structure of the present invention provides a phosphorescent tape with superior transfer characteristics and high luminous intensity compared to conventional tapes. An embodiment of the present invention will be described below with reference to FIGS. 2a and 2b and FIG. 3. First, a coating solution having the following composition is prepared.

Copper-activated zinc sulfide (ZnS/Cu) phosphor...
40 wax (paraffin wax)...
・・・・・・・・・ 4o dehydrated castor oil・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・ 2V Triclean・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・・・・
...100V, ie wax and dehydrated castor oil, are dissolved in trichlene and the phosphor is dispersed in this solution.

As for the dispersion method, the diameter is about 5m7! Apply approximately 100V to L glass beads and perform ball milling. After approximately 1 hour of milling, a well-stirred coating solution is obtained by removing the glass beads. The particle size of the resulting phosphor is shown in FIG. 2a.

In the figure, the horizontal axis shows the particle size of the phosphor, and the vertical axis shows the weight percent of the phosphor corresponding to each particle size. As is clear from the figure, the obtained phosphor contains about 88% particles having a particle size of 3 to 9 microns. The coating solution thus obtained is coated onto the tape by a coating device. The coating device will be briefly described below with reference to FIG.

First, a coating solution is applied to the unwinding roll 16 on which the tape (fluorescent powder coated) T1 is wound and the tape T1 unwound from this roll 16, and then the phosphorescent tape T2 obtained by drying is rolled up. It is equipped with a roll 17 and a solution application section.

(Note that the trichlene in the solution dissipates during drying.) The mechanism of the solution application section includes a container 15 containing the application solution 14,
A group of rollers 11, 12, 1 arranged above the container 15 at a constant interval and rotating in the same direction (arrow direction)
Consists of 3. This roller group 11, 12, 13 is
The first roller 11 is rotatably arranged so that at least the periphery of the roller is immersed in the coating solution 14 contained in the container 15, and the coating solution attached to the circumferential surface of the first roller 11 is removed. A second roller 12 is rotatably disposed opposite to the first roller 11 at a certain interval so as to inherit the second roller 12.
A third roller 13 is rotatably disposed above the second roller 12 at a constant interval. This third roller 13 uses a coating solution 14 applied to the circumferential surface of the second roller 12 in the process of winding up the tape T1 unwound from the unwinding roll 16 onto the winding roll 17.
The tape T1 is suspended so that the coating solution 14 is applied to one surface of the tape T1 in contact with the tape T1. Next, a method of applying the coating solution 14 onto the tape surface using such a coating device will be explained.

First, a tape T1 made of polyethylene phthalate having a thickness of about 10 μm is wound around the unwinding roll 16, and the tape T1 is passed between the second roller 12 and the third roller 13, and then the tape T1 is wrapped around the unwinding roll 16.
It is prepared to be wound onto a take-up roll IT via a dryer (not shown) and an auxiliary roller 18. On the other hand, the coating solution 14 sufficiently stirred and stored in the container 15 is transferred to the second roller 1 by the rotation of the roller groups 11, 12, and 13.
2.

Then, the tape T1 unwound by the rotation of the take-up roll IT and the unwinding roll 16 comes into contact with the coating solution 14 soaked in the circumferential surface of the second roller 12, and is coated with this solution 14.

The phosphorescent tape T2 that has passed through the dryer and been dried is wound around a winding roll 17. In the thus obtained phosphorescent tape, the grain size of the coating layer was very uniform because the particle size of the phosphor was uniform due to the use of the above-mentioned coating solution. Transfer this phosphorescent tape to the object to be transferred,
Furthermore, Table 1 shows the results of light emission by ultraviolet excitation in comparison with the case of using a conventional phosphor. In the table, the phosphor used in the conventional phosphorescent tape has a particle size distribution shown in FIG. 2b.

FIG. 2b shows the particle size of the phosphor on the horizontal axis and the weight percentage of the phosphor corresponding to each particle size on the vertical axis.

As can be seen from FIG. 2b, the particle sizes are generally distributed in the coarse direction, and approximately 59% of the particles are 9μ or larger. As can be seen from the results in Table 1, the phosphorescent tape according to the present invention has much better transferability and luminescence (emission intensity) than conventional tapes.

Note that the emission intensity is expressed as 100 when a conventional tape is used. Figure 4 is a graph showing the transfer rate of the phosphor tape with respect to the damage caused by particles with a particle size of 3 to 9 microns out of the total amount of phosphor in the coating solution, and the horizontal axis shows the phosphor The damage accounted for by 3 to 9μ of the total amount,
The vertical axis shows the transfer rate of phosphorescent tape using each phosphor.

As can be seen from this result, the amount of phosphor between 3 and 9μ is 70%.
It can be seen that if it is above, the transfer rate is 95% or more and sufficient transfer characteristics are exhibited. In the examples of the present invention, wax and dehydrated castor oil binders are used, but the present invention is not limited to these binders.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the phosphorescent tape, Figure 2a is a diagram showing the particle size distribution of the phosphor used in the phosphorescent tape of the present invention, and Figure 2b is the phosphor used in the conventional phosphorescent tape. Figure 3 is a schematic diagram showing a phosphorescent tape coating device;
FIG. 4 is a graph showing the transfer rate of a phosphor tape according to an embodiment of the present invention as a function of the content of particles with a particle size of 3 to 9 μm in the total amount of phosphor. 1... Base tape, 2... Fluorescent material,
3... Binder, 4, T2... Phosphorescent tape, 14... Coating solution, 16...
Tape unwinding roll, 17... Phosphorescent tape winding roll.

Claims (1)

[Claims] 1. In a phosphorescent tape comprising a coating layer consisting of a binder and a phosphor on the surface of a tape-shaped base material, the phosphor contains 70% by weight or more of the total phosphor with a particle size of 3 to 9 μm. Features of phosphorescent tape.