Ink jet recording method and ink jet recording apparatus
An ink jet recording method for recording an image on a recording medium by ejecting an aqueous ink from a print head of an ink jet recording apparatus includes applying an aqueous ink onto a recording medium, and cleaning a liquid contact member coming into contact with the aqueous ink in the ink jet recording apparatus with an aqueous cleaning liquid. The cleaning liquid contains a surfactant, a first water-soluble organic solvent with a lower vapor pressure than water, a second water-soluble organic solvent with an SP value, measured by a Fedors method, of 9.8 or more to 14.2 or less, and a third water-soluble organic solvent with a water retention capacity of 50% or less in an amount by mass of 0.7 or more relative to the total amount by mass of the water-soluble organic solvents. The cleaning liquid has a pH of 8.5 or more.
1 . An ink jet recording method for recording an image on a recording medium by ejecting an aqueous ink from a print head of an ink jet recording apparatus, the method comprising:
applying an aqueous ink onto a recording medium, the aqueous ink comprising a pigment and a resin particulate; and
cleaning a liquid contact member that comes into contact with the aqueous ink in the ink jet recording apparatus with an aqueous cleaning liquid,
wherein the ink jet recording apparatus includes a cleaning liquid supply path through which the cleaning liquid is supplied to the liquid contact member,
wherein the cleaning liquid comprises a surfactant, a first water-soluble organic solvent with a lower vapor pressure than water, a second water-soluble organic solvent with an SP value, measured by a Fedors method, of 9.8 or more to 14.2 or less, and a third water-soluble organic solvent with a water retention capacity of 50% or less in an amount by mass of 0.7 times or more relative to the total amount by mass of the water-soluble organic solvents, and the cleaning liquid has a pH of 8.5 or more,
wherein the first water-soluble organic solvent, the second water-soluble organic solvent, and the third water-soluble organic solvent are the same or different, and
wherein the water retention capacity is determined by allowing 10.0 g of 20% by mass aqueous liquid of the third water-soluble organic solvent placed in a laboratory dish to stand in an environment at a temperature of 30° C. and a relative humidity of 10%, measuring the mass of the residue in the laboratory dish when the mass no longer varies, and calculating the following equation (i):
Water
retention
capacity
(
%
)
=
[
mass
of
the
residue
in
the
laboratory
dish
(
g
)
-
2.
(
g
)
]
/
2.
(
g
)
.
(
i
)
2 . The ink jet recording method according to claim 1 , wherein the water retention capacity of the third water-soluble organic solvent is 30% or more.
3 . The ink jet recording method according to claim 1 , wherein the amount by mass (% by mass) of the third water-soluble organic solvent in the cleaning liquid is 0.9 times or more relative to the total amount by mass (% by mass) of the water-soluble organic solvents.
4 . The ink jet recording method according to claim 1 , wherein the liquid contact member includes a recovery mechanism for the print head.
5 . The ink jet recording method according to claim 1 , wherein the liquid contact member includes a supply mechanism for the aqueous ink.
6 . The ink jet recording method according to claim 1 , wherein the aqueous ink comprises at least one water-soluble organic solvent, and in the aqueous ink, the water-soluble organic solvent contained in the largest amount (% by mass) of the at least one water-soluble organic solvent has a higher vapor pressure (kPa) than the water-soluble organic solvent contained in the largest amount in the cleaning liquid.
7 . The ink jet recording method according to claim 1 , wherein the first water-soluble organic solvent in the cleaning liquid has a relative dielectric constant of 20.0 or more.
8 . The ink jet recording method according to claim 1 , wherein at least one of the water-soluble organic solvents in the cleaning liquid accounts for 10.0% by mass or more of the total mass of the cleaning liquid.
9 . The ink jet recording method according to claim 1 , wherein the cleaning liquid comprises a fourth water-soluble organic solvent with an SP value, measured by a Fedors method, of 9.8 or more to 12.2 or less in an amount of 10.0% by mass or less relative to the total amount by mass (% by mass) of the water-soluble organic solvents.
10 . The ink jet recording method according to claim 1 , wherein the surfactant in the cleaning liquid is a hydrocarbon-based nonionic surfactant with an HLB value, measured by a Griffin method, of 17 or less.
11 . The ink jet recording method according to claim 1 , wherein the cleaning liquid has a pH of 9.0 or more.
12 . The ink jet recording method according to claim 1 , further comprising applying an aqueous reaction liquid that reacts with the aqueous ink onto the recording medium.
13 . The ink jet recording method according to claim 1 , wherein the recording medium exhibits a water absorption of 10 mL/m 2 or less for a period of 30 ms 1/2 from the beginning of contact with water when measured by a Bristow method.
14 . An ink jet recording apparatus for recording an image on a recording medium by ejecting an aqueous ink from a print head, the apparatus comprising:
an ink application device configured to apply the aqueous ink onto a recording medium;
a cleaning device configured to clean a liquid contact member that comes into contact with the aqueous ink in the ink jet recording apparatus with an aqueous cleaning liquid; and
a cleaning liquid supply path through which the cleaning liquid is supplied to the liquid contact member,
wherein the aqueous ink contains a pigment and a water-soluble organic solvent with a higher vapor pressure than water,
wherein the cleaning liquid comprises a surfactant, a first water-soluble organic solvent with a lower vapor pressure than water, a second water-soluble organic solvent with an SP value, measured by a Fedors method, of 9.8 or more to 14.2 or less, and a third water-soluble organic solvent with a water retention capacity of 50% or less in an amount by mass of 0.7 times or more relative to the total amount by mass of the water-soluble organic solvents,
wherein the first water-soluble organic solvent, the second water-soluble organic solvent, and the third water-soluble organic solvent are the same or different, and
wherein the water retention capacity is determined by allowing 10.0 g of 20% by mass aqueous liquid of the third water-soluble organic solvent placed in a laboratory dish to stand in an environment at a temperature of 30° C. and a relative humidity of 10%, measuring the mass of the residue in the laboratory dish when the mass no longer varies, and calculating the following equation (i):
Water
retention
capacity
(
%
)
=
(
mass
(
g
)
of
the
residue
in
the
laboratory
dish
-
2.
(
g
)
)
/
2.
(
g
)
.
(
i
)