Inkjet head, method for producing inkjet head, inkjet recorder and inkjet coater

1. A method for producing an inkjet head for jetting an ink from a nozzle that is formed on a nozzle main body formed of a metal material, the method comprising:

smoothening a surface of the nozzle main body;

applying a silica sol solution to the nozzle main body so as to form a silica sol film, wherein the silica sol solution has a concentration that is controlled to avoid a nozzle clogging in the nozzle main body;

heating the silica sol film formed on the nozzle main body to thereby convert the silica sol film into an SiO 2 film;

applying an ink repellent agent solution to the SiO 2 film and drying to thereby form an ink repellent film, wherein the ink repellent agent solution is prepared by dissolving a compound having an alkoxysilane residue at an end of a perfluoro polyether chain in a solvent; and

removing an ink repellent film formed on a side to be in contact with an ink channel of the nozzle main body while remaining at least an ink repellent film formed on a surface of an ink jetting side of the nozzle main body.

2. The method for producing an inkjet heat according to claim 1 ,

wherein the compound having an alkoxysilane residue at an end of a perfluoro polyether chain is a compound represented by formulae:

F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )—X—Si(OR) 3

F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )—X—Si(OR) 2 R

F{CF 2 CF 2 CF 2 O) n CF 2 CF 2 —X—Si(OR) 3

F{CF 2 CF 2 CF 2 O) n CF 2 CF 2 —X—Si(OR 2 )R

[F{CF(CF 3 )—CF 2 O} n CF(CF 3 )] 2 —Y—Si(OR) 3

[F{CF(CF 3 )—CF 2 O} n CF(CF 3 )] 2 —Y—Si(OR) 2 R

{F(CF 2 CF 2 CF 2 O) n CF 2 CF 2 } 2 —Y—Si(OR) 3

{F(CF 2 CF 2 CF 2 O) n CF 2 CF 2 } 2 —Y—Si(OR) 2 R

wherein X and Y each represents a binding site of an alkoxysilane residue to a perfluoro polyether chain; and

R represents an alkyl group.

3. The method for producing an inkjet head according to claim 2 ,

wherein the alkoxysilane residue is —Si(OR) 3 .

4. The method for producing an inkjet head according to claim 2 ,

wherein each of the binding sites X and Y in the formulae respectively has a molecular structure represented by formulae:

—CONH—(CH 2 ) 3 —, —CH 2 O—(CH 2 ) 3 —, —CO 2 —(CH 2 ) 3 — or

—CH 2 NH—(CH 2 ) 3 — as —X—; and

5. A method for producing an inkjet head for jetting an ink from a nozzle that is formed on a nozzle main body formed of a metal material, the method comprising:

smoothening a surface of the nozzle main body;

forming an SiO 2 film on a surface of an ink jetting side of the nozzle main body; and

applying an ink repellent agent solution to the SiO 2 film and drying to thereby form an ink repellent film, wherein the ink repellent agent solution is prepared by dissolving a compound having an alkoxysilane residue at an end of a perfluoro polyether chain in a solvent.

6. The method for producing an inkjet heat according to claim 5 ,

wherein the compound having an alkoxysilane residue at an end of a perfluoro polyether chain is a compound represented by formulae:

F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )—X—Si(OR) 3

F{CF(CF 3 )—CF 2 O} n —CF(CF 3 )—X—Si(OR) 2 R

F{CF 2 CF 2 CF 2 O) n CF 2 CF 2 —X—Si(OR) 3

F{CF 2 CF 2 CF 2 O) n CF 2 CF 2 —X—Si(OR 2 )R

[F{CF(CF 3 )—CF 2 O} n CF(CF 3 )] 2 —Y—Si(OR) 3

[F{CF(CF 3 )—CF 2 O} n CF(CF 3 )] 2 —Y—Si(OR) 2 R

{F(CF 2 CF 2 CF 2 O) n CF 2 CF 2 } 2 —Y—Si(OR) 3

{F(CF 2 CF 2 CF 2 O) n CF 2 CF 2 } 2 —Y—Si(OR) 2 R

wherein X and Y each represents a binding site of an alkoxysilane residue to a perfluoro polyether chain; and

R represents an alkyl group.

7. The method for producing an inkjet head according to claim 6 ,

wherein the alkoxysilane residue is —Si(OR) 3 .

8. The method for producing an inkjet head according to claim 6 ,

wherein each of the binding sites X and Y in the formulae respectively has a molecular structure represented by formulae:

—CONH—(CH 2 ) 3 —, —CH 2 O—(CH 2 ) 3 —, —CO 2 —(CH 2 ) 3 — or

—CH 2 NH—(CH 2 ) 3 — as —X—; and

as —Y—.