JP2020187206A - Display screen protection film - Google Patents

Abstract

To allow a desired pattern, for example, to be seen clearly when a light is off, while preventing the pattern from being visible when a backlight is on and causing inconvenience in usage of an electronic apparatus.SOLUTION: A display screen protection film 11 has a streak part 14, which describes a desired display item on at least one surface, and is used by being attached to a display screen. The streak part 14 is formed by printing using a pearl ink obtained by mixing a transparent ink and a pearl pigment with each other. The amount of the pearl pigment added in the pearl ink is set in the range of 0.75 part to 1.75 part to 100 parts of the transparent ink.SELECTED DRAWING: Figure 1

Description

The present invention relates to a display screen protective film that is used by being attached to a display screen of an electronic device such as a smartphone or a tablet to protect the display screen from impacts, scratches, etc. and to decorate the display screen.

As a display screen protective film, as in Patent Document 1 below, the display content of the display screen is shown when the backlight of the display screen is on, but the desired display items can be seen when the backlight is turned off. There is.

The adhesive film for a display window of Patent Document 1 is composed of a lightly colored translucent film, and a display portion embossed with a hot stamp foil having at least a hologram embossing layer and a metal oxide layer on one side of the translucent film. It is provided. In this configuration, when the backlight is lit, the light is transmitted through the display unit and the display unit cannot be visually recognized. On the other hand, when the backlight is turned off, the display unit can be visually recognized in a transparent state.

In the cover glass disclosed in Patent Document 2, the display portion (decoration) is formed of unevenness having a predetermined average roughness by laser marking. With this cover glass, when the backlight is off, the light coming in from the outside is diffusely reflected in the decoration and becomes visible, while when the backlight is on, the light emitted from the backlight becomes dominant. The decoration becomes invisible.

In any of these cases, it is a major premise to adjust the hot stamp foil and the average roughness so that the display unit cannot be seen when the backlight is turned on. However, the hot stamp foil is easy to see, and it is difficult to hide the presence of the rough surface decoration as long as it exists as unevenness. For this reason, if the main focus is on making the display unit invisible when it is lit, the visibility when the backlight is turned off is inevitably weakened.

Japanese Patent No. 4349928 Japanese Patent No. 6153620

A main object of the present invention is to improve visibility when the backlight is turned off as well as not visible when the backlight is turned on.

The means for that is a display screen protection film having an image area on at least one side on which desired display items are drawn and used by attaching the image to the display screen, in which the image area mixes a pearl pigment with transparent ink. This is a display screen protection film formed by printing with the pearl ink, and the amount of the pearl pigment added to the pearl ink is set in the range of 0.75 to 1.75 with respect to 100 parts of the transparent ink.

In this configuration, when the image area is irradiated with light from below, the pearl ink having a transparent ink and a pearl pigment is a standard addition in which the amount of the pearl pigment added makes the pearl pigment exhibit its original function and glitters. It is less than the amount and mainly transmits light from below to prevent the image portion from being visually recognized from above. On the other hand, when there is no irradiation of light from below, the pearl pigment of the pearl ink that constitutes the image area reflects the incident light even if the amount is much smaller than the standard addition amount, and the interference color causes The transparent ink is raised so that the image area containing the pearl ink is clearly visible.

According to the present invention, the pearl ink is used for the image area, and the content of the pearl pigment in the pearl ink is set to an amount that allows the pearl pigment to be effectively used in the transparent ink for visibility when the light is turned off. While the image area is hidden when the ink is emitting light, the image area can be clearly seen when the display screen is off.

A perspective view of the display screen protective film. Enlarged sectional view of the display screen protective film. A plan view showing a state in which the display screen is turned off and on when the display screen protective film is used. The schematic diagram which shows the action of a pearl pigment. A photograph showing a state at the time of lighting in a comparative example. A photograph showing the state when the light is turned off in the comparative example.

An embodiment for carrying out the present invention will be described below with reference to the drawings.

FIG. 1 shows a perspective view of a display screen protective film 11 (hereinafter referred to as “film”) used by being attached to a display screen of an electronic device. The film 11 is used as an electronic device in a smartphone, and has a substantially rectangular shape having a shape suitable for being attached to a display screen of the smartphone.

As shown in the cross-sectional structure of FIG. 2, the film 11 includes the transparent film body 12 formed in a substantially rectangular shape, the adhesive layer 13 formed on the entire back surface of the film body 12, and the film body 12. It has an image portion 14 formed on the surface and depicting desired display items.

The film body 12 is made of a glass film, a resin film, or the like, and has high light transmission and hardness.

The adhesive layer 13 is made of an appropriate transparent material such as silicon.

The image line portion 14 displays characters, figures, patterns, patterns, and the like, and is formed by screen printing. The thickness of the image area is appropriately set. In the film 11 of FIG. 1, the image line portion 14 is represented by the letter “A”.

As the ink forming the image area 14, a pearl ink obtained by mixing a pearl pigment 16 with a transparent ink 15 is used. The addition amount of the pearl pigment 16 in the pearl ink is usually set to be smaller than the standard addition amount for pearl ink to express the characteristics of the pearl pigment 16. In the case of a pearl pigment having an average particle size of 20 μm, the standard addition amount is 30 to 40 parts with respect to 100 parts of the ink, but in the case of the pearl ink constituting the image portion 14, the lower limit of the standard addition amount is 40 minutes. It is 1 or more and 1/10 or less of.

Expressed in comparison with the transparent ink, the amount of the pearl pigment added to the pearl ink may be set in the range of 0.75 to 1.75 with respect to 100 parts of the transparent ink.

The amount of the pearl pigment added to the pearl ink is also related to the particle size and the interference color of the pearl pigment.

When the particle size of the pearl pigment is relatively large, the addition amount is set to be small, and when the particle size is relatively small, the addition amount is set to be large as compared with the case where the particle size is large. Specifically, when the particle size of the pearl pigment is 10 μm or more and 40 μm or less, in other words, the median diameter is 18 μm or more and 25 μm or less, the amount of the pearl pigment added to the pearl ink is 0.75 with respect to 100 parts of the ink. Set in the range from 1 part to 1.25 parts. When the particle size of the pearl pigment is 5 μm or more and 30 μm or less, in other words, the median diameter is 10 μm or more and less than 18 μm, the amount of the pearl pigment added to the pearl ink is 1.25 to 1.75 parts with respect to 100 parts of the ink. Set to the range of parts.

When the interference color of the pearl pigment is a strongly visible color such as silver, the amount of the pearl pigment added is set to be smaller than that of a color such as blue or purple. Specifically, when the interference color of the pearl pigment is silver, it is set to about 60 to 70% of the case where the interference color of the pearl pigment is a dark color such as blue or purple.

The pearl pigment has a white appearance, and the interference color of the pearl pigment can be selected from appropriate colors such as gold, silver, red, purple, and blue.

As the transparent ink constituting the pearl ink, "13 screen ink" manufactured by Teikoku Printing Inks, Ltd. was used.

As the pearl pigment, the "TWINCLEPEAL (registered trademark)" series manufactured by Nippon Koken Kogyo Co., Ltd. was used.
Table 1 lists the type names, interference colors, glosses, particle size distributions, and median diameters of the pearl pigments used.

The pearl ink was prepared with the following formulation. The dilution amount was 15%.
[Pearl ink SXB] Use "SXB-SO" with silver interference color and add 1.5 parts to 100 parts of transparent ink [Pearl ink SXC] Use "SXC-SO" with silver interference color. Add 1.0 part to 100 parts of transparent ink [Pearl ink YXC] Add 1.0 part to 100 parts of transparent ink using "YXC-SO" with golden interference color [Pearl ink RXC ] 1.0 part is added to 100 parts of transparent ink using "RXC-SO" with red interference color [Pearl ink VXC] 100 parts of transparent ink using "VXC-SO" with purple interference color [Pearl ink BXC] 1.0 part was added to 100 parts of transparent ink using "BXC-SO" with blue interference color. These pearl inks were described above. The image area was formed by screen printing on the same material as the film body. The printing plate is 270 to 280 mesh, and has a film thickness (emulsion thickness) of 6 μm, a wire diameter of 35 μm, an opening ratio of 56 μm, an aperture ratio of 38%, a gauze thickness of 53 μm, and a total thickness of 59 μm.

In the case of a film using any of the pearl inks, a film having such an image portion looks like there is no image portion at first glance when light enters from both the front surface side and the back surface side. The appearance was such that the presence of the image area could be vaguely recognized as a pale white part if you gazed at it. Therefore, in FIG. 1, the image line portion 14 is represented by a virtual line.

As shown in FIG. 3, when the film 11 was actually attached to the smartphone 21 and the states of the display screen 22 when it was turned off and when it was turned on were confirmed, the image portion 14 was clearly visible when the display screen 22 was turned off (FIG. 3). 3 (a)), the image line portion 14 could not be visually recognized at the time of lighting (see FIG. 3 (b)). In this method, as shown in FIG. 4A, when the light is turned off, the pearl pigment 16 in the pearl ink reflects the light incident from the surface side, and the entire portion of the transparent ink 15 is made to shine with an interference color, on the other hand. This is because the back side is dark and there is no light incident. When lit, as shown by a virtual line in FIG. 4B, although light is incident from the front surface side, the light transmitted from the display screen to the back surface side is strong and the content of the pearl pigment 16 is small. Therefore, the reflected light by the pearl pigment 16 is drowned out.

As a comparative example, the following pearl inks were prepared.
[Pearl Ink SXC-1] Using "SXC-SO" with silver interference color, add 2.0 parts to 100 parts of transparent ink [Pearl Ink SXC-2] "SXC-SO" with silver interference color ], Add 1.5 parts to 100 parts of transparent ink [Pearl Ink SXC-3] Using "SXC-SO" with silver interference color, 0.5 parts to 100 parts of transparent ink [Pearl ink VXC-1] Using "VXC-SO" with purple interference color, add 2.0 parts to 100 parts of transparent ink [Pearl ink VXC-2] "VXC-2" with purple interference color Add 1.5 parts to 100 parts of transparent ink using "-SO" [Pearl Ink VXC-3] Use "VXC-SO" with purple interference color to add 0 parts to 100 parts of transparent ink. 5 parts added [Pearl Ink BXC-1] 2.0 parts added to 100 parts of transparent ink using "BXC-SO" with blue interference color [Pearl Ink BXC-2] Interference color is blue Add 1.5 parts to 100 parts of transparent ink using "BXC-SO" [Pearl Ink BXC-3] Use "BXC-SO" with blue interference color to add 1.5 parts to 100 parts of transparent ink. 0.5 part was added These pearl inks were screen-printed on the same material as the film body described above to form an image area. The printing conditions are the same as described above.

When a film having such an image portion was attached to the display screen of a smartphone and the visual state of the image portion was compared between when it was turned off and when it was turned on, the following results were obtained.

When the amount of pearl pigment added is 0.5 parts, that is, in the case of [Pearl Ink SXC-3], [Pearl Ink VXC-3], and [Pearl Ink BXC-3], any film using any pearl ink can be used. When lit, the image area is invisible, that is, it disappears, and the display screen of the smartphone can be viewed without stress. However, the visibility of the image area when the light was turned off was not sufficient, and it was difficult to see.

When the amount of pearl pigment added is 2.0 parts, that is, in the case of [Pearl Ink SXC-1], [Pearl Ink VXC-1], and [Pearl Ink BXC-1], any film using any pearl ink can be used. When the lights were turned off, the image area was clearly visible. However, even when it was lit, the image area could be visually recognized without disappearing, making it difficult to see the display screen of the smartphone. A photograph of the film using [Pearl Ink SXC-1] when the film is turned off is shown in FIG. 5, and a photograph when the film is turned on is shown in FIG.

With [Pearl Ink SXC-1], in which 1.5 parts of pearl pigment having a silver interference color was added, which was more than 1.0 part, the image area could be visually recognized even when it was lit. On the other hand, in the case of [Pearl Ink VXC-1] having a purple interference color and [Pearl Ink BXC-1] having a blue interference color, even if the amount of addition is large, 1.5 parts are lit. Sometimes the image area was not visible.

As described above, the image line portion formed by using the pearl ink obtained by adding a predetermined small amount of pearl pigment to the transparent ink is not visible from the surface side when the display screen emits light, and the display screen is turned off. When it is in a state, it reflects the light entering from the surface side to clearly see its existence. For this reason, the image area does not get in the way when the electronic device is in use, and when the electronic device display screen is not used, the desired display items are clearly displayed and decorated. It can be used for identification, etc.

The configuration described above is a mode for carrying out the present invention, and the present invention is not limited to the above-mentioned configuration, and other configurations can be adopted.

For example, the formation of the image line portion on the film body can be performed not only on the surface but also on both sides or on both sides.

11 ... Display screen protection film 14 ... Image area 15 ... Transparent ink 16 ... Pearl pigment

Claims (3)

A display screen protection film that has an image area on at least one side on which desired display items are drawn and is used by being attached to a display screen.
The image area is formed by printing with pearl ink, which is a mixture of transparent ink and pearl pigment.
A display screen protection film in which the amount of pearl pigment added to the pearl ink is set in the range of 0.75 to 1.75 with respect to 100 parts of the transparent ink. The particle size of the pearl pigment is 18 μm or more and 25 μm or less in terms of median diameter.
The display screen protective film according to claim 1, wherein the amount of the pearl pigment added to the pearl ink is set in the range of 0.75 to 1.25 parts with respect to 100 parts of the ink. The particle size of the pearl pigment is 10 μm or more and less than 18 μm in median diameter.
The display screen protective film according to claim 1, wherein the amount of the pearl pigment added to the pearl ink is set in the range of 1.25 parts to 1.75 parts with respect to 100 parts of the ink.