Multicolor electronic devices and processes of forming the same by printing
View Patent ↗There is provided a method of printing a regular array of rows of subpixels on a workpiece. The subpixels have c different colors and have a subpixel pitch s. A printing head has z nozzles arranged in a row with a spacing p, where z=n 1 (c) and p=n 2 (s), the printhead being at a first position relative to the workpiece. There are c different printing inks, one for each of the c colors, and each of the printing inks is supplied to the nozzles in a regular alternating pattern. The method includes steps of printing a first set of z rows of subpixels with the printing head; moving the workpiece laterally relative to the printing head by a distance d 1 , where d 1 =n 3 (s); printing a second set of z rows of subpixels with the printing head; repeating the printing steps for a total of n 2 sets of z rows of subpixels. Variables include: c, an integer greater than 1; n 1 , n 2 , and n 3 which are the same or different and are independently selected from integers greater than 0, with the proviso that n 2 is not a multiple of c.
1. A method of printing a regular array of rows of electrically active subpixels on a workpiece for use in an organic electronic device, wherein the subpixels are capable of emitting light having c different colors and having a subpixel pitch s, said method comprising:
(a) providing a printing head having z nozzles arranged in a row with a spacing p, where z=n 1 (c) and p=n 2 (s), the printing head being at a first position relative to the workpiece;
(b) providing c different color printing inks to the printing head, one color printing ink for each of the c colors, and wherein each color printing ink contains an electroluminescent material;
(c) supplying each nozzle on the printing head with color printing ink in an alternating pattern, wherein adjacent nozzles on the printing head are not supplied the same color;
(d) dispensing said color printing ink from the z nozzles to print a first set of z rows of subpixels with the printing head;
(e) moving the workpiece laterally relative to the printing head by a distance d 1 , where d 1 =n 3 (s);
(f) dispensing said color printing ink from the nozzles to print a second set of z rows of subpixels with the printing head; and
(g) repeating steps (e) and (f) for a total of n 2 sets of z rows of subpixels;
where:
c is an integer greater than 1;
n 1 , n 2 , and n 3 are the same or different and are independently selected from integers greater than 0, with the proviso that n 2 is not a multiple of c.
2. The method of claim 1 , further comprising moving the workpiece laterally relative to the printing head to a second printing position, wherein the printing head is moved by a distance of d 2 from the first printing and d 2 =n 2 zs, and repeating steps (d) through (g).
3. The method of claim 1 , wherein c=2, 3, or 4.
4. The method of claim 1 , wherein n 1 is at least 2.
5. The method of claim 1 , wherein n 2 =c+1.
6. The method of claim 1 , wherein n 3 =n 4 c, where n 4 is an integer greater than 0.
7. The method of claim 1 , wherein c=2, n 1 =4-8, n 2 =3, and n 3 =2.
8. The method of claim 1 , wherein c=3, n 1 =3-5, n 2 =4, and n 3 =3.
9. The method of claim 1 , wherein c=4, n 1 =2-4, n 2 =5, and n 3 =4.
10. The method of claim 1 wherein the dispensing steps (d) and (f) are performed in a continuous spray for each set of z rows of subpixels.