System and method for dispensing material

Patent metadata

Field	Value
Publication number	US-10933156-B2
Application number	US-202016902407-A
Country	US
Kind code	B2
Filing date	Jun 16, 2020
Priority date	Feb 1, 2018
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A fluid dispensing method, the method comprising steps of: providing a system comprising a reservoir, a micro-fluidic thermal inkjet print head in fluid communication with the reservoir, a controller and a power source in electrical communication with the controller and the print head, the reservoir containing a fluid, the micro-fluidic thermal inkjet print head comprising nozzles; heating the fluid in the microfluidic device to a temperature of about 40 C to 75 C in less than about 1000 ms; activating the print head to fire the nozzles about 200 fires/nozzle at a first frequency; subsequent to step c, activating the print head to fire the nozzles at a second frequency, the second frequency substantially less than the first frequency; and subsequent to step d, activating the print head to fire the nozzles at a third frequency substantially greater than the first frequency.

First claim

What is claimed is:

1. A method for dispensing fluids, the method comprising steps of:
a. providing a system comprising a reservoir, a micro-fluidic thermal inkjet print head in fluid communication with the reservoir, a controller and a power source in electrical communication with the controller and the print head, the reservoir containing a fluid, the micro-fluidic thermal inkjet print head comprising nozzles;
b. heating the fluid in the microfluidic device to a temperature of about 40 C to 75 C in less than about 1000 ms;
c. activating the print head to fire the nozzles at a first frequency; and
d. subsequent to step c, activating the print head to fire the nozzles at a second frequency, the second frequency substantially less than the first frequency.

2. The method according to claim 1 wherein the first frequency is between about 800 Hz and about 1500 Hz.

3. The method according to claim 1 wherein the second frequency is between about 1 Hz and about 10 Hz.

4. The method according to claim 1 wherein the second frequency is about 5 Hz.

5. The method according to claim 1 wherein the first frequency is about 1000 Hz.

6. The method according to claim 1 wherein the method further comprises the step of activating the nozzles for about 200 activations per nozzle.

7. The method according to claim 6 wherein the step of activating the nozzles for about 200 activations per nozzle is after step b and before step c.

8. The method according to claim 1 wherein the step of heating the fluid comprises heating the fluid to a temperature of about 65 C.

9. The method according to claim 1 wherein the step of providing a micro-fluidic thermal inkjet print head comprises providing a thermal inkjet print head comprising a thermal fluid recirculation element.

10. The method according to claim 1 wherein the step of providing a fluid comprises providing a fluid comprising:
a. a particulate material having a Particle Size Distribution D50 of 100 nm to 2,000 nm;
b. a (meth)acrylic acid homopolymer or salt thereof having a weight average molecular weight of less than 20,000 daltons; and
c. a rheology modifier, wherein the rheology modifier is selected from the group consisting of alkali swellable emulsion polymers, hydrophobically modified alkali swellable emulsion polymers, and combinations thereof;
wherein the fluid has a first dynamic viscosity of greater than 1,100 cP at a shear rate of 0.1 sec- 1 measured at 25 C and a second dynamic viscosity of less than 100 cP at a shear rate of 1,000 sec- 1 measured at 25 C.

11. A method for dispensing fluids, the method comprising steps of:
a. providing a system comprising a reservoir, a micro-fluidic thermal inkjet print head in fluid communication with the reservoir, a controller and a power source in electrical communication with the controller and the print head, the reservoir containing a fluid, the micro-fluidic thermal inkjet print head comprising nozzles, wherein the fluid has a shear dependent viscosity;
b. heating the fluid in the microfluidic device to a temperature of about 40 C to 75 C in less than about 1000 ms;
c. activating the print head to fire the nozzles to dispense the fluid at a first dynamic viscosity of greater than 1,100 cP at a shear rate of 0.1 sec- 1 measured at 25 C; and
d. activating the print head to fire the nozzles to dispense the fluid at a second dynamic viscosity of less than 100 cP at a shear rate of 1,000 sec- 1 measured at 25 C.

Assignees

• Procter & Gamble

Inventors

• Bush Stephan Gary

Classifications

• A45D34/00 Primary

  Containers or accessories specially adapted for handling liquid toiletry or cosmetic substances, e.g. perfumes · CPC title

• B41J2/18

  Ink recirculation systems · CPC title

• B41J2/38

  Preheating, i.e. heating to a temperature insufficient to cause printing · CPC title

• B41J2/175

  Ink supply systems {; Circuit parts therefor} · CPC title

• B41J2/04528

  aiming at warming up the head · CPC title