Ink tank, ink jet recording method, and ink tank regeneration process
AssigneeCanon Kabushiki Kaisha
InventorsYoshihide Aikawa, Kuniaki Fujimoto, Sadayuki Sugama
Life of this patent
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Abstract
The present invention aims to provide an ink tank which can elongate the lifetime of ink jet recording apparatus and further stores therein an ink which can achieve superior image characteristics such as image fastness. The present invention provides an ink tank which comprises an ink storage portion storing an aqueous ink therein, having fine channels which retain the aqueous ink by capillary force, wherein the aqueous ink comprises at least water and a water-soluble coloring material, and further comprises a compound satisfying specific requirements.
Claims14
An ink tank which comprises an ink storage portion for storing an aqueous ink therein, having fine channels which retain the aqueous ink by capillary force, wherein;
- the aqueous ink comprises at least water and a water-soluble coloring material;
- and
- the aqueous ink further comprises a compound satisfying the following requirements (1) to (4):
- Requirement (1):
- a molecular weight of the compound is less than a molecular weight of the water-soluble coloring material;
- Requirement (2):
- part of molecular structure of the compound is similar to part of molecular structure of the water-soluble coloring material;
- Requirement (3):
- the number of carboxyl groups per molecule of the compound is more than the number of carboxyl groups per molecule of the water-soluble coloring material;
- and
- Requirement (4):
- a solubility of the compound in pure water with pH7 at 25° C. is lower than the solubility of the water-soluble coloring material in pure water with pH7 at 25° C.
An ink tank which comprises an ink storage portion storing an aqueous ink therein, having fine channels which retain the aqueous ink by capillary force, wherein;
- the aqueous ink comprises at least water and a water-soluble coloring material;
- the water-soluble coloring material comprises a compound represented by the following general formula (I) or a salt thereof;
- and
- the aqueous ink further comprising a compound represented by the following general formula (II):
- wherein R1 represents a hydrogen atom, an alkyl group, a hydroxy lower alkyl group, a cyclohexyl group, a monoalkylaminoalkyl or dialkylaminoalkyl group, or a cyano lower alkyl group;
- Y represents a chlorine atom, a hydroxyl group, an amino group, or a monoalkylamino or dialkylamino group which may have a substituent selected from the group consisting of a sulfonic group, a carboxyl group and a hydroxyl group on an alkyl group;
- and R2, R3, R4, R5 and R6 each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a carboxyl group, provided that R2, R3, R4, R5 and R6 cannot simultaneously represent hydrogen atoms;
- and
- wherein R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a carboxyl group or a salt thereof, provided that at least two of the R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 are carboxyl groups or salts thereof;
- and X represents a chlorine atom, a hydroxyl group, an amino group, or a monoalkylamino or dialkylamino group having 1 to 3 carbon atoms.
An ink tank which comprises an ink storage portion storing an aqueous ink therein, having fine channels which retain the aqueous ink by capillary force, wherein;
- the aqueous ink comprises at least water and a water-soluble coloring material, and the aqueous ink further comprises a compound represented by the following general formula (II):
- wherein R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a carboxyl group or a salt thereof, provided that at least two of the R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 are carboxyl groups or salts thereof;
- and X represents a chlorine atom, a hydroxyl group, an amino group, or a monoalkylamino or dialkylamino group having 1 to 3 carbon atoms.
An ink tank regeneration process for regenerating an ink tank which comprises an ink storage portion storing an aqueous ink therein, having fine channels which retain the aqueous ink by capillary force;
- the aqueous ink comprising at least water and a water-soluble coloring material;
- and
- the aqueous ink further comprising, as a compound satisfying the following requirements (1) and (2), a compound represented by the following general formula (II);
- and
- the process comprising a dissolution step of dissolving the compound, which has come deposited in the interior of the ink tank, by the use of an aqueous solution having a pH of 10.0 or more:
- Requirement (1):
- a molecular weight of the compound represented by the general formula (II) is less than a molecular weight of the water-soluble coloring material;
- and
- Requirement (2):
- the compound represented by the general formula (II) has lower solubility in pure water with pH 7 at 25° C., than the water-soluble coloring material:
- wherein R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a carboxyl group or a salt thereof, provided that at least two of the R7, R8, R9, R10, R11, R12, R13, R14, R15 and R16 are carboxyl groups or salts thereof;
- and X represents a chlorine atom, a hydroxyl group, an amino group, or a monoalkylamino or dialkylamino group having 1 to 3 carbon atoms.
Dependencies are inferred from the claim text.