An object of an embodiment of the present invention is to provide a biodegradable polyester solution that exhibits good solubility in a halogen-free organic solvent and that has sufficient adhesive strength even when aged for a short time. The object is achieved by providing a biodegradable polyester solution containing a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer and a solvent, the poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) copolymer having an average content of 16 mol % or more 3-hydroxyhexanoate.

The present disclosure describes ink compositions having a polyurethane binder that can be used for textile printing. In one example, an ink composition can include water, an organic co-solvent, a colorant, and a polyurethane binder. The polyurethane binder can include pre-polymer segments that include polymerized monomers of a diisocyanate, a graft diol, a polymeric diol, and an acid-containing diol. The graft diol can include thioglycerol having a polymer sidechain replacing a hydrogen atom on a sulfur atom of the thioglycerol. The polymer sidechain can include a polymerized monomer of an acrylate ester, a methacrylate ester, a styrene, or a combination thereof. The polyurethane binder can also include chain extenders connecting the pre-polymer segments. The chain extenders can include a polymerized sulfonate-containing diamine.

The present disclosure describes ink compositions having a polyurethane binder that can be used for textile printing. In one example, an ink composition can include water, an organic co-solvent, a colorant, and a polyurethane binder. The polyurethane binder can include pre-polymer segments that include polymerized monomers of a diisocyanate, a graft diol, a polymeric diol, and an acid-containing diol. The graft diol can include thioglycerol having a polymer sidechain replacing a hydrogen atom on a sulfur atom of the thioglycerol. The polymer sidechain can include a polymerized monomer of an acrylate ester, a methacrylate ester, a styrene, or a combination thereof. The polyurethane binder can also include chain extenders connecting the pre-polymer segments. The chain extenders can include a polymerized sulfonate-containing diamine.

Provided are an ink set including a first ink including an ethylenic unsaturated compound and a photopolymerization initiator, the first ink not including a colorant or including a white colorant, and a second ink including an ethylenic unsaturated compound, a photopolymerization initiator, and a colorant, wherein the proportion of the amount of a monofunctional monomer to the total amount of the ethylenic unsaturated compound included in the first ink is 95.0% by mass or more, the proportion of the amount of a monofunctional monomer to the total amount of the ethylenic unsaturated compound included in the second ink is 95.0% by mass or more, and, when the static surface tension of the first ink at 25° C. is defined as T1 and the static surface tension of the second ink at 25° C. is defined as T2, the value calculated by subtracting T1 from T2 is 1 mN/m or more, and applications of the ink set.

Provided are an ink set including a first ink including an ethylenic unsaturated compound and a photopolymerization initiator, the first ink not including a colorant or including a white colorant, and a second ink including an ethylenic unsaturated compound, a photopolymerization initiator, and a colorant, wherein the proportion of the amount of a monofunctional monomer to the total amount of the ethylenic unsaturated compound included in the first ink is 95.0% by mass or more, the proportion of the amount of a monofunctional monomer to the total amount of the ethylenic unsaturated compound included in the second ink is 95.0% by mass or more, and, when the static surface tension of the first ink at 25° C. is defined as T1 and the static surface tension of the second ink at 25° C. is defined as T2, the value calculated by subtracting T1 from T2 is 1 mN/m or more, and applications of the ink set.

Provided is an image recording method including a step of preparing an ink containing water and a white pigment, and a step of jetting the ink from an ink jet head in a liquid droplet amount of 1.0 pL or greater to apply the ink onto a base material, in which in a case where an ink jetting surface of the ink jet head is immersed in the ink in a vertically standing state for 2 seconds, the jetting surface is pulled up from the ink in the state, and the jetting surface is allowed to stand in the state for 1 minute, a ratio of an area of a region to which the ink is adhered to an area of the jetting surface is 40% by area or less.

Provided is an image recording method including a step of preparing an ink containing water and a white pigment, and a step of jetting the ink from an ink jet head in a liquid droplet amount of 1.0 pL or greater to apply the ink onto a base material, in which in a case where an ink jetting surface of the ink jet head is immersed in the ink in a vertically standing state for 2 seconds, the jetting surface is pulled up from the ink in the state, and the jetting surface is allowed to stand in the state for 1 minute, a ratio of an area of a region to which the ink is adhered to an area of the jetting surface is 40% by area or less.

A recording method includes: discharging a water-based recording ink onto a recording medium to record an image, determining whether the recording medium is a coated paper or a non-coated paper; heating the recording medium or the water-based recording ink adhered to the recording medium with a cumulative heating amount Q1 when the recording medium is determined to be a coated paper; and with a cumulative heating amount Q2 smaller than the cumulative heating amount Q1 when the recording medium is determined to be a non-coated paper. The water-based recording ink includes: a resin dispersion pigment; a fine resin particle; a water-soluble organic compound; and water. A melting point of the water-soluble organic compound is within a range of 20 to 55° C. A viscosity of a 50 mass % aqueous solution of the water-soluble organic compound is 8.5 mPa.Math.s or more at 20° C. and 90 mPa.Math.s or less at 50° C.

A recording method includes: discharging a water-based recording ink onto a recording medium to record an image, determining whether the recording medium is a coated paper or a non-coated paper; heating the recording medium or the water-based recording ink adhered to the recording medium with a cumulative heating amount Q1 when the recording medium is determined to be a coated paper; and with a cumulative heating amount Q2 smaller than the cumulative heating amount Q1 when the recording medium is determined to be a non-coated paper. The water-based recording ink includes: a resin dispersion pigment; a fine resin particle; a water-soluble organic compound; and water. A melting point of the water-soluble organic compound is within a range of 20 to 55° C. A viscosity of a 50 mass % aqueous solution of the water-soluble organic compound is 8.5 mPa.Math.s or more at 20° C. and 90 mPa.Math.s or less at 50° C.

The present invention relates to semiconducting nanoparticle.