Printhead integrated circuit attachment film having differentiated adhesive layers
View Patent ↗A laminated film for attachment of printhead integrated circuits to an ink supply manifold. The film has a plurality of ink supply holes defined therein and film comprises: a central polymeric film; a first adhesive layer for bonding a first surface of the film to the ink supply manifold; and a second adhesive layer for bonding a second surface of the film to the printhead integrated circuits. The central polymeric film is sandwiched between the first and second adhesive layers. A first melt temperature of the first adhesive layer is at least 20° C. less than a second melt temperature of the second adhesive layer.
1. A printhead assembly comprising:
an ink manifold having a plurality of ink outlets defined in a manifold bonding surface;
one or more printhead integrated circuits, each printhead integrated circuit having a plurality of ink inlets defined in a printhead bonding surface; and
a laminated film sandwiched between said manifold bonding surface and said one or more printhead bonding surfaces, said film having a plurality of ink supply holes defined therein, each ink supply hole being aligned with a respective ink outlet and an ink inlet, said laminated film comprising:
a central polymeric film;
a first adhesive layer bonded to said manifold bonding surface; and
a second adhesive layer bonded to said one or more printhead bonding surfaces, said central polymeric film being sandwiched between said first and second adhesive layers,
wherein a first melt temperature of said first adhesive layer is at least 10° C. less than a second melt temperature of said second adhesive layer.
2. The printhead assembly of claim 1 , wherein each ink supply hole is substantially free of any adhesive.
3. The printhead assembly of claim 1 , wherein said first and second adhesive layers each have a uniform thickness along a longitudinal extent of said printhead assembly.
4. The printhead assembly of claim 1 , wherein a first bonding surface of said first adhesive layer and a second bonding surface of said second adhesive layer are uniformly planar along a longitudinal extent of said printhead assembly.
5. The printhead assembly of claim 1 comprising a plurality of printhead integrated circuits butted end on end along a longitudinal extent of said ink supply manifold.
6. The printhead assembly of claim 5 , wherein said plurality of printhead integrated circuits define a printhead having a uniformly planar ink ejection face.
7. The printhead assembly of claim 1 , wherein said printhead assembly exhibits a leakage rate of less than 5 mm 3 per minute when charged with air at 10 kPa, said leakage rate being measured after soaking said printhead assembly in ink at 90° C. for one week.
8. The printhead assembly of claim 1 , wherein a plurality of ink inlets are defined by an ink supply channel extending longitudinally along said printhead bonding surface, and wherein a plurality of ink supply holes are aligned with one ink supply channel, each of said plurality of ink supply holes being spaced apart longitudinally along said ink supply channel.
9. The printhead assembly of claim 1 , wherein said ink supply manifold is an LCP molding.