Hydrophilic foam having improved fluid retention
A fluid ejection cartridge having a cartridge body with a cavity therein and an ejection head attached to an external surface of the cartridge body opposite the cavity. A cylindrical or a rectangular-prism shaped body made of a hydrophilic open-cell foam material is disposed in the cavity of the cartridge body. The cylindrical or rectangular-prism shaped body has at least one uncoated hydrophilic surface and two or more surfaces coated with a hydrophobic material.
1 . A fluid ejection cartridge comprising:
a cartridge body having a cavity therein and an ejection head attached to an external surface of the cartridge body opposite the cavity, and
a cylindrical or a rectangular-prism shaped body comprised of a hydrophilic open-cell foam material disposed in the cavity of the cartridge body, wherein the cylindrical or rectangular-prism shaped body further comprises at least one uncoated hydrophilic surface and two or more surfaces fully coated with a hydrophobic material,
wherein the hydrophilic open-cell foam material comprises a melamine foam material.
2 . The fluid ejection cartridge of claim 1 , wherein the hydrophobic material is reactive with the two or more coated surfaces of the melamine foam material.
3 . The fluid ejection cartridge of claim 2 , wherein the hydrophobic material cross-links and encapsulates fibers of the melamine foam material.
4 . A fluid ejection cartridge comprising:
a cartridge body having a cavity therein and an ejection head attached to an external surface of the cartridge body opposite the cavity, and
a cylindrical or a rectangular-prism shaped body comprised of a hydrophilic open-cell foam material disposed in the cavity of the cartridge body, wherein the cylindrical or rectangular-prism shaped body further comprises at least one uncoated hydrophilic surface and two or more surfaces fully coated with a hydrophobic material,
wherein the hydrophobic material is selected from the group consisting of fluorinated hydrocarbons, siloxanes, hydrocarbon compounds having from 6 to 20 carbon atoms, and coating compounds that provide a contact angle of greater than 90 degrees.
5 . The fluid ejection cartridge of claim 1 , wherein a rectangular prism-shaped hydrophilic open-cell foam body has one uncoated hydrophilic surface and five surfaces fully coated with the hydrophobic material.
6 . The fluid ejection cartridge of claim 1 , wherein the cylindrical or rectangular prism-shaped hydrophilic open-cell foam body has only one uncoated hydrophilic surface.
7 . The fluid ejection cartridge of claim 1 , wherein the two or more surfaces have a hydrophobic coating thickness ranging from about 2 nm to about 500 μm.
8 . The fluid ejection cartridge of claim 4 , wherein a rectangular prism-shaped hydrophilic open-cell foam body has one uncoated hydrophilic surface and five surfaces fully coated with the hydrophobic material.
9 . The fluid ejection cartridge of claim 4 , wherein the cylindrical or rectangular prism-shaped hydrophilic open-cell foam body has only one uncoated hydrophilic surface.
10 . The fluid ejection cartridge of claim 4 , wherein the two or more surfaces have a hydrophobic coating thickness ranging from about 2 nm to about 500 μm.