US 5,508,086 AGranted

Electrostatic notice board system

AssigneeAbisare Co., Ltd.

InventorKeiji Kasahara

Life of this patent

Estimating the term…

Loading patent…

Abstract

An electrostatic notice board system in which characters can be written on the surface while attraction force sufficient to hold objects thereon being maintained. In the system, a hard coating material layer is formed at the surface off the attraction layer consisting of a layered dielectric substance and the back face of the attraction layer is provided with a pair of positive and negative electrodes in the form of comb-teeth, so that the objects such as paper sheets are attracted and held by coulomb force on the surface of the hard coating material layer. The hard coating material layer is, for example, formed by applying acrylic urethane coating material to the surface of the attraction layer and hardening the material with ultraviolet ray irradiation. The hard coating material layer has a volume resistivity of 10.sup.10 .OMEGA. cm or more and thickness of 50 .mu. or less.

Claims21

Dependent claims

An electrostatic notice board system for use with a power source comprising:

(a) a dielectric attraction layer:
(b) a hard coating material layer having a volume resistivity of 10.sup.10 .OMEGA.cm or more and having a hardness of at least 3 H, the hard coating material layer on one face side of the attraction layer;
and
(c) at least a pair of electrodes on the other face side of the attraction layer such that the electrodes are electrically separated from each other, said electrodes adapted to be connected to the power source for generating an electric field in order to cause a polarization charge at the attraction layer;
wherein said attraction layer, said hard coating material layer and said electrodes form a laminate structure;
and
wherein an object placed on the one face side of the attraction layer with the hard coating material layer interposed between the object and the attraction layer can be attracted and held by means of a coulomb force resulting from the electric field.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/091,556Filed 14 Jul 1993
Priority: JP 4-20250329 Jul 1992
Granted: 16 Apr 1996
Term ends: Not estimatedThe source records don’t support an estimate.

Classification16 codes

B43L 5/02
Drawing boards: having means for clamping sheets of paper thereto
B43L 1/002
Repeatedly-usable boards or tablets for writing or drawing: chemical details
G09F 7/12
Signs, plates, panels or boards using readily-detachable elements bearing or forming symbols: the elements being secured or adapted to be secured…
G09F 2007/125
The elements being secured or adapted to be secured by self-adhesion, moisture, suction, slow-drying adhesive or the like: by electrostatic force