Abstract: Provided is an optical apparatus including: a first supporter disposed on one end side of an optical element in a longitudinal direction thereof and supporting a first or second surface thereof; a second supporter disposed on the other end side thereof in the longitudinal direction and supporting a portion of the first surface on one end side of the optical element in a shorter direction thereof; and a third supporter disposed on the other end side thereof in the longitudinal direction and supporting a portion of the first or second surface on the other end side thereof in the shorter direction. A pressing force of a presser pressing the optical element to a side of the second and the third supporter is set to be larger than a pressing force of a first pressing member pressing the optical element to a side of the first supporter.

Abstract: An ink jet recording device of the present disclosure is an ink jet recording device including an ink amount detection device that includes a container internally having an accommodation space that accommodates an ink jet ink composition, a first electrode and at least one second electrode disposed to face each other via the accommodation space, and a capacitance detection unit detecting a capacitance between the first electrode and the second electrode using a mutual capacity method, in which the ink jet ink composition has an electrical conductivity of 10.0 mS/cm or less.

Abstract: An ink jet ink composition includes a pigment formed of a self-dispersing pigment A having a volume average particle diameter D50 of 150 nm or less and containing a phosphorus-containing group, and a self-dispersing pigment B having a volume average particle diameter D50 of 90 nm or greater and 150 nm or less and containing a functional group other than the phosphorus-containing group.

Abstract: An ink jet ink composition includes: an acetoacetanilide-based monoazo pigment coated with a water-insoluble polymer; 1-(2-hydroxyethyl)-2-pyrrolidone; and water.

Abstract: An ink jet composition according to an embodiment of the present disclosure is an ink jet composition which is ejected from an ink jet head, the ink jet head has a nozzle plate in which nozzles are formed and a flow path substrate which is bonded to one surface of the nozzle plate and in which flow paths including a liquid storage chamber to store a liquid to be supplied to the nozzles are formed, the liquid storage chamber is formed of a recess provided in a surface of the flow path substrate opposite to the nozzle plate, and the ink jet composition has a surface tension of 31 mN/m or less at 25° C.

Abstract: A microwave irradiation device includes: a retainer configured to retain an irradiated object at a retaining position; a power feed tool configured to electrically be conductive with an oscillator; a power feed antenna configured to emit a microwave by power feed through conduction via the power feed tool, the power feed antenna having directivity and being arranged with an irradiation axis facing the retaining position; and a parasitic antenna that has directivity but is not fed with power, the parasitic antenna being arranged to face the power feed antenna across the retaining position and having an irradiation axis facing the retaining position.

Abstract: An ink set includes a process color ink set including a yellow ink, a magenta ink, a cyan ink, and a black ink as process color inks, and a light ink having a color similar to a corresponding one of the process color inks in the process color ink set. The yellow ink, the magenta ink, and the cyan ink each have a maximum absorption wavelength, and each have a full width at half maximum of a peak including the maximum absorption wavelength. A maximum absorbance in a visible light wavelength range of the light ink is 70% or less of a maximum absorbance in the visible light wavelength range of the corresponding one of the process color inks.

Abstract: A microwave irradiation device including: a holder that holds an irradiated object; a power feeder configured to conduct with an oscillator; and a directional antenna configured to emit microwaves from an irradiation source in an irradiation surface by power feed through conduction via the power feeder.

Abstract: An ink jet recording device of the present disclosure is an ink jet recording device including an ink amount detection device that includes a container internally having an accommodation space that accommodates an ink jet ink composition, a first electrode and at least one second electrode disposed to face each other via the accommodation space, and a capacitance detection unit detecting a capacitance between the first electrode and the second electrode using a mutual capacity method, in which the ink jet ink composition has an electrical conductivity of 10.0 mS/cm or less.

Abstract: An ink jet composition according to an embodiment of the present disclosure is an ink jet composition which is ejected from an ink jet head, the ink jet head has a nozzle plate in which nozzles are formed and a flow path substrate which is bonded to one surface of the nozzle plate and in which flow paths including a liquid storage chamber to store a liquid to be supplied to the nozzles are formed, the liquid storage chamber is formed of a recess provided in a surface of the flow path substrate opposite to the nozzle plate, and the ink jet composition has a surface tension of 31 mN/m or less at 25° C.

Abstract: A water-based ink jet ink composition contains Pigment Yellow 150, a dispersing resin, and N-hydroxyethylpyrrolidone.

Abstract: An ink jet ink composition includes: an acetoacetanilide-based monoazo pigment coated with a water-insoluble polymer; 1-(2-hydroxyethyl)-2-pyrrolidone; and water.

Abstract: An ink jet recording apparatus includes an ink composition, an ink encasement in which the ink composition is encased, a recording head that ejects the ink composition, and a carriage configured to move the recording head back and forth. The carriage carries the ink encasement, with the ink encasement integrated with the carriage. The ink encasement has an ink fill port that opens and shuts as a port through which the ink composition is loaded. The ink composition contains a disperse colorant, with the volume-average particle diameter of the disperse colorant being 110.0 nm or more and 200.0 nm or less, and also contains at least one organic solvent with an SP of 9 or more, with the percentage thereof being 10.0% by mass or more.

Abstract: An ink jet recording apparatus includes an ink composition, an ink encasement in which the ink composition is encased, a recording head that ejects the ink composition, and a carriage configured to move the recording head back and forth. The carriage carries the ink encasement, with the ink encasement integrated with the carriage. The ink encasement has an ink fill port that opens and shuts as a port through which the ink composition is loaded. The ink composition contains a water-soluble dye and a polyhydric alcohol with a normal boiling point of 270° C. or above, with the percentage of the polyhydric alcohol being 26.0% by mass or less of the total amount of the ink composition.

Abstract: An ink jet recording apparatus includes an ink composition, an ink encasement in which the ink composition is encased, a recording head that ejects the ink composition, and a carriage configured to move the recording head back and forth. The carriage carries the ink encasement, with the ink encasement integrated with the carriage. The ink encasement has an ink fill port that opens and shuts as a port through which the ink composition is loaded. The ink composition contains a disperse colorant, with the volume-average particle diameter of the disperse colorant being 105.0 nm or less.

Abstract: An ink jet recording apparatus includes an ink composition, an ink encasement in which the ink composition is encased, a recording head that ejects the ink composition, and a carriage configured to move the recording head back and forth. The carriage carries the ink encasement, with the ink encasement integrated with the carriage. The ink encasement has an ink fill port that opens and shuts as a port through which the ink composition is loaded and also has a detector that detects the amount of ink composition encased. The ink composition contains a surfactant with an HLB of 6 or less.

Abstract: An aqueous ink-jet ink composition according to the present disclosure contains pigment, water, resin particles, 1-(2-hydroxyethyl)-2-pyrrolidone, and trimethylglycine. The mass-based content of the resin particles is lower than the mass-based content of the pigment.

Abstract: An ink jet ink composition of the present disclosure includes a coloring material, water, an acetylene glycol-based surfactant having a HLB value of 4 or less, and 1-(2-hydroxyethyl)-2-pyrrolidone. The content of 1-(2-hydroxyethyl)-2-pyrrolidone in the ink jet ink composition is 0.5% by mass or more and 5.0% by mass or less.

Abstract: An aqueous ink jet ink composition contains a color material, water, 1-(2-hydroxyethyl)-2-pyrrolidone, and a 1,2-alkanediol. The mass ratio of the content of the 1-(2-hydroxyethyl)-2-pyrrolidone and that of the 1,2-alkanediol is 1:10 to 10:1.

Abstract: An aqueous ink jet ink composition contains a color material, water, a polyhydric alcohol having a standard boiling point of 270.0° C. or more, and 1-(2-hydroxyethyl)-2-pyrrolidone. The mass ratio of the content of the polyhydric alcohol to that of 1-(2-hydroxyethyl)-2-pyrrolidone is 3.1 or more and 7.0 or less.