JPH0333511Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic panel suitable for marker display and capable of preventing halation caused by reflected light.

[Conventional technology]

As shown in FIG. 3, a conventional magnetic panel has a multi-cell structure 3 between two substrates consisting of a transparent resin top plate 1 and a bottom plate 2, and magnetic particles 4 ( It has a structure in which a colored dispersion liquid 5 (usually a white liquid) in which a colored dispersion liquid 5 (usually a black liquid) is dispersed is enclosed. In this case, the transparent resin top plate 1
It is stable against colored dispersion liquids, has enough strength to withstand local pressure applied by a magnetic pen, can be attached to multi-cell structures, has good transparency, does not deform due to environmental temperature, etc. Due to these conditions, polar resins such as vinyl chloride resin and polyester are currently used.

When a display magnetic field from a magnetic pen is applied to display on such a magnetic panel, the magnetic particles 4 to which the magnetic field has been applied are gathered on the front plate 1 side, and the contrast between the color of the magnetic particles 4 and the color of the dispersion liquid 5 is increased. Characters with difference
When a figure can be displayed and an erasing magnetic field is applied from the bottom plate 2 side of the magnetic panel, the magnetic particles 4 migrate to the bottom plate 2 side, and the top plate 1 side of the magnetic panel becomes only the color of the colored dispersion liquid 5, and the display can be erased. It is.

[Problem that the invention attempts to solve]

However, when the top plate 1 is simply made of a polar resin such as vinyl chloride resin or polyester,
Incident light from an external light source is specularly reflected on the front and back surfaces of the front panel, and depending on the viewing position of the magnetic panel,
A so-called halation phenomenon occurs in which displayed characters and figures are difficult to see. That is, as shown in FIG. 4, light A ₀ that enters the top plate 1 from an external light source, such as an indoor fluorescent light, is reflected at _two points B ₁ and B on the top plate 1, and the light A 0 is reflected from points A ₁ and A ₂ . It becomes light and interferes with reading the characters and figures on the magnetic panel with the naked eye. This is thought to be because the refractive index of the vinyl chloride resin and polyester resin forming the top plate 1 is relatively large, 1.53 and 1.65, respectively, and the degree of dispersion of the reflected lights A ₁ and A ₂ is small. Incidentally, magnetic panels are moving toward increasing their display area and displaying more characters and figures, but the larger the magnetic panel, the more likely it is that halation will occur, so a solution to this problem is desired.

Furthermore, when a top board made of polar resin is copied with a regular whiteboard marker, the polar resin has an adhesive force with the ink in the marker, and when erasing the handwriting, it may not be possible to erase it at all, or even if it is erased, the handwriting remains. There is a problem in that a stain remains, making it unsuitable for marker display. In other words, if the surface to which the ink is to be attached is not non-polar, no matter how much the ink is adjusted to have low surface tension and high vapor pressure, the relationship between the ink particles after drying and the surface to which the ink is to be attached is Because of its strong affinity, it cannot be easily wiped off with erasers such as cloth or soft paper.

This invention was made based on the above circumstances,
The object of the present invention is to provide a magnetic panel suitable for displaying markers and capable of preventing halation caused by reflected light.

[Means for solving problems]

This invention consists of a transparent polar resin top plate and a bottom plate.
In a magnetic panel in which a multi-cell structure is formed between the two substrates, and a colored dispersion liquid in which magnetic particles are dispersed that migrate under the action of a magnetic field is sealed in the cells, the top plate is placed on the transparent polar resin top plate. It is characterized by providing a transparent non-polar resin layer having a refractive index different from the refractive index.

〔Example〕

To explain this invention based on the drawings, as shown in FIG.
A transparent non-polar resin layer 1a having a refractive index different from that of the top plate 1 is newly provided thereon.

In this case, the layer 1a may be formed by coating a material in the form of paint, or may be formed by simply overlapping sheets or films.

With such a configuration, the incident light A ₀ is transmitted to layer 1
The reflected light of A ₃ to A ₅ is dispersed at the B ₃ points of a and the B ₄ and B ₅ points of the top plate 1, and the halation can be weakened. ~1.45) is the refractive index of the top plate 1 (e.g.
1.46 to 1.70) is more effective. Furthermore, since layer 1a is non-polar, the ink marks can be erased by writing on layer 1a with a regular whiteboard marker and then wiping it gently with cloth or paper.

The top plate 1 is selected from among, for example, vinyl chloride resin (refractive index 1.53), polyester (refractive index 1.65), cellulose acetate (refractive index 1.50), polycarbonate (refractive index 1.55), etc.

Examples of the layer 1a include tetrafluoroethylene copolymer (refractive index 1.40), trifluoroethylene copolymer (refractive index 1.35), polyvinylidene fluoride (refractive index 1.42), and ethylene-olefin copolymer (refractive index 1.48). , polypropylene (1.51)
etc., and you can choose from these.

FIG. 2 shows another example of the case where the layer 1a is provided, and the difference from FIG. It is different from the case.

With such a configuration, the incident light A ₀ is transmitted to layer 1
₆ B points on a, ₇ B points on layer 1b, and B ₈ and B ₉ on top plate 1
At the point, the reflected light from A ₆ to _{A 9} is dispersed, and halation can be further weakened. This prevention of halation is also more effective when the refractive index of the layer 1a (for example, 1.30 to 1.45) is smaller than the refractive index of the top plate 1 (for example, 1.46 to 1.70).

[Effect of idea]

As explained in detail above, the present invention provides a transparent non-polar resin layer with a refractive index different from that of the transparent polar resin top plate of the magnetic panel, making it suitable for marker display. This provides a magnetic panel that can prevent halation caused by light.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a magnetic panel top plate provided with a transparent non-polar resin layer as an embodiment of the present invention, FIG. 2 is a schematic diagram showing another example of providing a transparent non-polar resin layer, and FIG. The figure is a cross-sectional view of a conventional magnetic panel.
The figure is a schematic diagram showing the relationship between the top plate and halation in FIG. 3. In the figure, 1 is a transparent polar resin top plate, 1a is a transparent non-polar resin layer, 1b is a transparent adhesive layer, 2 is a bottom plate, 3 is a multi-cell structure, 4 is a magnetic particle, and 5 is a colored dispersion liquid.

Claims (1)

[Claims for Utility Model Registration] A multi-cell structure is formed between two substrates consisting of a transparent polar resin top plate and a bottom plate, and a colored dispersion liquid in which magnetic particles that migrate due to the action of a magnetic field are dispersed is sealed in the cells. 1. A magnetic panel comprising: a transparent non-polar resin layer having a refractive index different from the refractive index of the top plate on the transparent polar resin top plate.