Water-soluble ink, ink jet printer and method of printing thereof

An aqueous ink composition having a high wettability to plastic surfaces in contact with the ink comprising a water soluble dye having the chemical structure formula:

• ##STR47## where R.sub.1 to R 4 each represents one of an OH group and a NH.sub.2 group and comprising an amount in the range of about 0.1 wt. % to 10.0 wt. % of the aqueous ink,
• and at least one of a surfactant comprising an acetylene glycol surfactant comprising an amount in the range of about 0.01 wt. % to 0.1 wt. % of the ink having a chemical structure formula:
• ##STR48## and an acetylene glycol-ethylene oxide adduct surfactant comprising an amount in the range of about 0.01 wt. % to 10 wt % of the aqueous ink having a chemical formula:
• ##STR49## wherein a sum of m and n are each integers of at least 1.

An ink jet printer comprising a plastic molded body having interior plastic surfaces including a plurality of ink ports each connected in a first direction to a first end respective of a plurality of respective ink pressure chambers and connected in a second direction to a respective one of a plurality of ink output nozzles, a common ink supply port connected a second end of said ink pressure chambers, an aqueous ink composition having a wetting property to said plastic surfaces, said aqueous ink comprising a water soluble dye having the chemical structure formula:

• ##STR50## wherein R.sub.1 to R.sub.4, are one of an OH group and a NH.sub.2 group in the range of about 0.1 wt. % to 10.0 wt. % of the aqueous ink,
• and at least one of a surfactant comprising an acetylene glycol surfactant comprising an amount in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink having a chemical structure formula:
• ##STR51## and an acetylene glycol-ethylene oxide adduct surfactant comprising an amount in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink having a chemical structure formula:
• ##STR52## wherein a sum of m and n is in the range from 1 to 5 inclusive.

An aqueous ink composition comprising a water soluble dye having the chemical structure formula:

• ##STR53## wherein R.sub.1 to R.sub.4, are one of an OH group and a NH.sub.2 group in the range of about 0.1 wt. % to 10.0 wt % of the aqueous ink,
• and a first surfactant in the range of about 0.01 wt. % to 0.1 wt. % of the ink comprising an acetylene glycol surfactant having a chemical structure formula:
• ##STR54## a second surfactant having at least one of a first portion in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink comprising an acetylene glycol-ethylene oxide adduct surfactant having a chemical formula:
• ##STR55## wherein a sum of m and n is in the range from 1 to 5, inclusive, and a second portion in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink comprising acetylene glycol-ethylene oxide adduct surfactant having a chemical formula:
• ##STR56## wherein a sum of m and n is in the range of 6 to 40, inclusive.

An aqueous ink composition having high wettability to plastic surfaces in contact with the ink comprising a water soluble dye having the chemical structure formula:

• ##STR57## where R.sub.1 to R.sub.4 each represents one of an OH group and a NH.sub.2 group and comprising an amount in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink,
• and at least one of a surfactant comprising acetylene glycol surfactant comprising an amount in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink having a chemical formula:
• ##STR58## and an acetylene glycol-ethylene oxide adduct surfactant comprising an amount in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink having a chemical formula:
• ##STR59## wherein a sum of m and n is in the range of 6 to 40, inclusive.

A method of producing an aqueous ink composition comprising the steps of providing a water soluble dye having the chemical structure formula:

• ##STR60## wherein R.sub.1 to R.sub.4 are one of an OH group and a NH.sub.2 group in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink,
• and adding to the aqueous ink at least one of the first surfactant in the range of about 0.01 wt. % to 0.1 wt. % of the ink comprising an acetylene glycol surfactant having a chemical structure formula:
• ##STR61## and a second surfactant having at least one of the first portion in the range of about 0.01 wt. % to 0.1 wt. % of the ink comprising an acetylene glycol-ethylene oxide adduct surfactant having a chemical structure formula:
• ##STR62## wherein a sum of m and n is in the range of 1 to 5 inclusive, and a second portion in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink comprising an acetylene glycol-ethylene oxide adduct surfactant having a chemical structure formula:
• ##STR63## wherein a sum of m and n is in the range of 6 to 40 inclusive.

A method of printing on a recording medium comprising the steps of, providing an ink jet printer comprising a plastic molded body having interior plastic surfaces including a plurality of ink ports each connected in a first direction to a first end of respective of a plurality of respective ink pressure chambers and connected in a second direction to a respective one of a plurality of ink output nozzles, a common ink supply port connected a second end of said ink pressure chambers, an aqueous ink composition having a wetting property to said plastic surfaces, said aqueous ink comprising a water soluble dye having the chemical structure formula:

• ##STR64## wherein R.sub.1 to R.sub.4 are one of an OH group and a NH.sub.2 group in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink,
• and at least one of a first surfactant in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink comprising an acetylene glycol surfactant having a chemical structure formula:
• ##STR65## and a second surfactant having at lease one of a first portion in the range of about 0.01 wt. % to 0.1 wt. % of the aqueous ink comprising an acetylene glycol-ethylene oxide adduct surfactant having a chemical structure formula:
• ##STR66## and wherein a sum of m and n is of in the range of 1 to 5 inclusive, and a second portion in the range of about 0.1 wt. % to 10 wt. % of the aqueous ink comprising an acetylene glycol-ethylene oxide adduct surfactant having a chemical structure formula:
• ##STR67## and wherein a sum of m and n is in the range of 6 to 40 inclusive;
• and ejecting the ink through the output nozzles toward the recording medium.