Spin-printing of electronic and display components
View Patent ↗Processes for printing conductors, insulators, dielectrics, phosphors, emitters, and other elements containing elongated functional particles aligned along the axis of a spun fiber or film that can be for electronics and display applications are provided. Also provided are viscoelastic compositions used in the processes, and devices made therefrom.
1. A process comprising:
(a) forcing a deposit composition through an orifice to form a fiber, wherein the composition comprises from 0.1 to 50 percent by weight of elongated functional particles based upon the total weight of the composition, a dispersing vehicle, and from 0.1 to 8 percent by weight of a polymer having a molecular weight of at least about 1,000,000 that is soluble in that dispersing vehicle;
(b) drawing the fiber to a draw ratio from 2 to 100; and
(c) depositing the fiber on a substrate; evaporating the dispersing vehicle from the deposited fiber resulting in the elongated functional particles affixed to the substrate in a desired image.
2. A process comprising:
(a) depositing on the surface of a substrate, from a dispensing orifice, a reservoir of a deposit composition comprising from 0.1 to 50 percent by weight of elongated functional particles based upon the total weight of the composition, a dispersing vehicle, and from 0.1 to 8 percent by weight of a polymer having a molecular weight of at least about 1,000,000 that is soluble in that dispersing vehicle such that the dispensing orifice and the substrate are simultaneously wet by the material in the reservoir;
(b) pulling a fiber from the reservoir by removing the dispensing orifice from the reservoir and away from the surface of the substrate translating the orifice to a location above a second point on the substrate at least 1 cm removed from the initial reservoir such that the fiber extends between the reservoir and the location above that second point;
(c) depositing that fiber between the reservoir and the second point on the substrate by contacting the dispensing orifice to the substrate at the second point; and
(d) evaporating the dispersing vehicle from the deposited fiber resulting in the elongated functional particles being affixed to the substrate in a desired image.
3. The process of claim 1 or claim 2 wherein a) and b) are carried out continuously.
4. The process of claim 1 or claim 2 wherein the fiber is a sheath/core fiber.
5. The process of claim 4 wherein the sheath consists of a fugitive polymer.
6. The process of claim 4 wherein the polymer content of the sheath is higher than that of the core.
7. The process of claim 4 wherein the sheath comprises a polymer containing an insulating component and the core comprises a polymer containing a conductive component, and wherein the insulating component contains encapsulated conductors on the substrate after firing.
8. The process of claim 1 or claim 2 in which two or more sequential layers of the printing composition are printed onto the substrate adjacent to and contacting each other.
9. The process of claim 1 or claim 2 in which two or more sequential layers of the printing composition are printed onto the substrate and in which the two or more layers contain different active components, different adjuvants or different active components and adjuvants.
10. The process of claim 1 or claim 2 wherein the surface of the substrate has been chemically modified to have a surface energy different than that of the natural surface energy of the substrate to make it more non-wetting to minimize spreading of the deposit composition.
11. The process of claim 10 , further comprising modifying a first portion of the substrate to have a surface energy that is different than the surface energy on a second portion of the substrate, and wherein the first portion is adapted to confine the deposited composition.
12. The process of claim 10 , further comprising modifying a first portion of the substrate, wherein the first portion is adapted to confine the deposited composition.
13. The process of claim 1 or claim 2 wherein the temperature of the deposit composition is higher than the temperature of the surface of the substrate.
14. The process of claim 1 or claim 2 wherein the temperature of the deposit composition is lower than the temperature of the surface of the substrate.
15. The process of claim 1 or claim 2 wherein the substrate comprises one or more channels and the deposit composition is deposited into one or more channels on the substrate.
16. The process of claim 1 or claim 2 wherein the substrate is rigid.
17. The process of claim 1 or claim 2 wherein the substrate is selected from glass, ceramics and polymers.
18. The process of claim 17 wherein the substrate is a semiconductor.
19. The process of claim 1 or claim 2 wherein the substrate is flexible.
20. The process of claim 1 or claim 2 wherein the fiber from the orifice is touched to the substrate to establish adhesion between the fiber and the substrate.
21. The process of claim 1 or claim 2 wherein the width of the image is modulated by modulating the draw ratio of the fiber.