Plastic and nonmetallic article shaping or treating: processes – Optical article shaping or treating – Composite or multiple layer
Reexamination Certificate
2000-12-28
2003-02-25
Vargot, Mathieu D. (Department: 1732)
Plastic and nonmetallic article shaping or treating: processes
Optical article shaping or treating
Composite or multiple layer
C264S004400, C264S007000, C264S008000, C425S008000
Reexamination Certificate
active
06524500
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates generally to visual displays and to gyricon or twisting-element displays.
2. Description of Related Art
Gyricon, or twisting, particles, such as balls and cylinders, are used to make gyricon displays. A gyricon display is also referred to as electric paper. A gyricon display comprises twisting particles that individually rotate to display a desired surface or a desired aspect of transparency of the particles to an observer.
Twisting particles can be, for example, a ball having two distinct hemispheres with both an optical anisotropy and an electrical anisotropy due to each hemisphere surface having a different color and electrical charge. The twisting particles are generally embedded in a fluid-filled cavity of a substrate. The substrate is then generally bonded between glass or plastic sheets to create a gyricon display. When an electric field is presented over the display, the twisting particles within the substrate rotate in reaction to the electric field by rotating in the fluid. U.S. Pat. Nos. 4,126,854 to Sheridon and 4,143,103 to Sheridon each incorporated herein by reference in its entirety, describe conventional twisting ball displays each.
Gyricon displays ideally have characteristics and qualities of conventional paper, such as flexibility. However, conventional gyricon displays are not paper-like because they are generally too rigid. A further discussion of the disadvantages of conventional gyricon displays is found in U.S. Pat. No. 5,064,027 to Sheridon, which is incorporated herein by reference in its entirety.
In an effort to make the gyricon displays more paper-like, attempts have been made to individually encapsulate the twisting particles. This is called microencapsulation. Microencapsulated twisting particles are then incorporated into a flexible substrate without needing a protective sheet of glass or plastic.
A conventional approach to microencapsulating a twisting particle centers on a chemical process where the twisting particles are first produced using conventional methods and then are subsequently immersed and treated in chemical solutions, resulting in a capsule, as disclosed in the '027 patent.
SUMMARY OF THE INVENTION
Chemical methods of microencapsulating gyricon beads require numerous additional steps in making a display and thus add substantially to the cost of making the display. Further, there is a limited yield in the chemical methods and errors occur that are difficult to eliminate. Among the errors it is found that some microcapsules do not contain balls and others contain two or more balls. Capsules that do not contain balls subtract from the contrast of the display and capsules that contain two or more balls do not exhibit good ball rotation because of interference between the balls, again causing a loss in contrast. Still further, the chemical processes used in producing the microencapsulation of the balls have been found to be incompatible with the chemistry of the balls, on occasion, limiting the types of balls that can be microencapsulated.
This invention provides methods of both fabricating gyricon beads and in the same instant process, microencapsulating each said ball singly in a liquid-filled capusle.
This invention separately provides methods of microencapsulating a twisting particle. This invention separately provides methods for microencapsulating a twisting particle, that do not use chemical processes.
This invention separately provides methods for making a micro-capsule containing a bichromal bead and a liquid that engulfs the bichromal bead.
This invention separately provides a method for making a microencapsulated gyricon bead based on the differences of the surface tensions of the respective materials that form various layers and/or portions of the microencapsulated gyricon bead.
These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the systems and methods according to this invention.
REFERENCES:
patent: 2326634 (1943-08-01), Gebhard et al.
patent: 2354018 (1944-07-01), Heltzer et al.
patent: 2354048 (1944-07-01), Palmquist
patent: 2354049 (1944-07-01), Palmquist et al.
patent: 2407680 (1946-09-01), Palmquist
patent: 2600963 (1952-06-01), Bland
patent: 2684788 (1954-07-01), Bland
patent: 2794301 (1957-06-01), Law et al.
patent: 2950985 (1960-08-01), Duval d'Adrian
patent: 2965921 (1960-12-01), Bland
patent: 2980547 (1961-04-01), Duval D'Adrian
patent: 3150947 (1964-09-01), Bland
patent: 3222204 (1965-12-01), Weber et al.
patent: 3243273 (1966-03-01), Bland
patent: 3310391 (1967-03-01), Law
patent: 3617333 (1971-11-01), Brown
patent: 3648281 (1972-03-01), Dahms et al.
patent: 3795435 (1974-03-01), Schwab
patent: 3915771 (1975-10-01), Gatzke et al.
patent: 4002022 (1977-01-01), Lopez
patent: 4082426 (1978-04-01), Brown
patent: RE29742 (1978-08-01), Tung
patent: 4117192 (1978-09-01), Jorgensen
patent: 4117194 (1978-09-01), Barbe et al.
patent: 4126854 (1978-11-01), Sheridon
patent: 4143103 (1979-03-01), Sheridon
patent: 4229732 (1980-10-01), Hartstein et al.
patent: 4261653 (1981-04-01), Goodrich
patent: 4267946 (1981-05-01), Thatcher
patent: 4268413 (1981-05-01), Dabisch
patent: 4288788 (1981-09-01), Rogers et al.
patent: 4299880 (1981-11-01), Arens
patent: 4367920 (1983-01-01), Tung et al.
patent: 4374889 (1983-02-01), Arens
patent: 4381616 (1983-05-01), Saxer
patent: 4418098 (1983-11-01), Maistrovich
patent: 4438160 (1984-03-01), Ishikawa et al.
patent: 4441791 (1984-04-01), Hornbeck
patent: 4492435 (1985-01-01), Banton et al.
patent: 4500172 (1985-02-01), Gagnon et al.
patent: 4511210 (1985-04-01), Tung et al.
patent: 4569857 (1986-02-01), Tung et al.
patent: 4592628 (1986-06-01), Altman et al.
patent: 4678695 (1987-07-01), Tung et al.
patent: 4688900 (1987-08-01), Doane et al.
patent: 4695528 (1987-09-01), Dabisch et al.
patent: 4710732 (1987-12-01), Hornbeck
patent: 4713295 (1987-12-01), Laroche
patent: 4721649 (1988-01-01), Belisle et al.
patent: 4725494 (1988-02-01), Belisle et al.
patent: 4729687 (1988-03-01), Arens
patent: 4810431 (1989-03-01), Leidner
patent: 4837071 (1989-06-01), Tagoku et al.
patent: 4877253 (1989-10-01), Arens
patent: 4890902 (1990-01-01), Doane et al.
patent: 4919521 (1990-04-01), Tada et al.
patent: 4948232 (1990-08-01), Lange
patent: 4956619 (1990-09-01), Hornbeck
patent: 4991941 (1991-02-01), Kalmanash
patent: 4994204 (1991-02-01), Doane et al.
patent: 5039557 (1991-08-01), White
patent: 5075186 (1991-12-01), Sheridon
patent: 5128203 (1992-07-01), LaRoche
patent: 5155607 (1992-10-01), Inoue et al.
patent: 5157011 (1992-10-01), Okabe et al.
patent: 5189658 (1993-02-01), Moses
patent: 5219820 (1993-06-01), Morohoshi et al.
patent: 5226099 (1993-07-01), Mignardi
patent: 5249000 (1993-09-01), Okabe et al.
patent: 5251048 (1993-10-01), Doane et al.
patent: 5262098 (1993-11-01), Crowley et al.
patent: 5262374 (1993-11-01), Okabe et al.
patent: 5274460 (1993-12-01), Yamada et al.
patent: 5315418 (1994-05-01), Sprague et al.
patent: 5315776 (1994-05-01), Strawbridge et al.
patent: 5331454 (1994-07-01), Hornbeck
patent: 5344594 (1994-09-01), Sheridon
patent: 5354598 (1994-10-01), Arens
patent: 5363222 (1994-11-01), Ledebuhr
patent: 5383008 (1995-01-01), Sheridon
patent: 5384067 (1995-01-01), Doane et al.
patent: 5389426 (1995-02-01), Arens et al.
patent: 5389945 (1995-02-01), Sheridon
patent: 5397503 (1995-03-01), Yuasa et al.
patent: 5416996 (1995-05-01), Clemens et al.
patent: 5432526 (1995-07-01), Hyatt
patent: 5432534 (1995-07-01), Maruyama et al.
patent: 5459602 (1995-10-01), Sampsell
patent: 5469020 (1995-11-01), Herrick
patent: 5515075 (1996-05-01), Nakagiri et al.
patent: 5526016 (1996-06-01), Nakagiri et al.
patent: 5535047 (1996-07-01), Hornbeck
patent: 5604027 (1997-02-01), Sheridan
patent: 5767826 (1998-06-01), Sheridan et al.
patent: 5891479 (1999-04-01), Sheridon
patent: 40 08825 (1991-03-01), None
patent: 2161301 (1973-07-01), None
patent: SHO 5357998 (1978-05-01), None
Lawrence L. L
Chopra Naveen
Khonsari Nassim
Sheridon Nicholas K.
Oliff & Berridg,e PLC
Vargot Mathieu D.
Xerox Corporation
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