JP2023135166A - polyurethane dispersion - Google Patents

Abstract

To provide a polyurethane dispersion which is excellent in color development property and adhesion, followability to deformation of a fabric, and storage stability, when a fabric is printed.SOLUTION: A polyurethane dispersion is obtained by water dispersion of a polyurethane resin. The polyurethane resin is a reaction product of an isocyanate group-terminated prepolymer, and a chain extender. The isocyanate group-terminated prepolymer is a reaction product of a polyisocyanate component, and a polyol component containing macropolyol and a hydrophilic group-containing active hydrogen compound. The macropolyol contains aromatic ring-containing macropolyol containing an alkylene oxide adduct of a compound having a bisphenol skeleton. The alkylene oxide addition amount of the alkylene oxide adduct of the compound having the bisphenol skeleton is a predetermined value. The total of the acid value of the polyurethane resin, the urethane group concentration and the urea group concentration, and the aromatic ring concentration are predetermined values.SELECTED DRAWING: Figure 1

Description

The present invention relates to polyurethane dispersions.

BACKGROUND ART Conventionally, it has been known to print textiles by ejecting droplets of an ink composition from a nozzle using an inkjet method. The ink composition includes, for example, a coloring material and a resin that disperses the coloring material. Furthermore, when the coloring material is a pigment, the ink composition includes a binder resin for physically fixing the pigment to the fabric.

As such a resin, for example, a pigment dispersant containing a urethane resin obtained by reacting a polyester polyol obtained by reacting isophthalic acid and a polyol, a polyol having a hydrophilic group, and a polyisocyanate has been proposed. (For example, see Example 2 of Patent Document 1 below.)

Furthermore, an aqueous pigment composition has been proposed that contains, as a binder resin, a urethane resin obtained by reacting a polyester polyol obtained by reacting isophthalic acid and a polyol, a polyol having a hydrophilic group, and a polyisocyanate. (For example, see Example 2 of Patent Document 1 below.)

Japanese Patent Application Publication No. 2015-174876 Japanese Patent Application Publication No. 2015-163678

On the other hand, when printing fabric (particularly chemical fiber), the fabric may be pretreated in order to improve the interaction between the fabric and the ink composition.

When the fabric is pretreated, the ink composition aggregates on the surface of the fabric due to the interaction between the fabric and the ink composition, thereby suppressing the ink composition from seeping into the fabric. This increases the color density (improves color development) on the surface of the fabric. On the other hand, when the penetration of the ink composition into the fabric is suppressed, the adhesion between the fabric and the ink composition is reduced. In other words, color development and adhesion have a trade-off relationship.

Further, if the resin attached to the surface of the fabric does not follow the deformation of the fabric, the resin may peel off. Therefore, the resin is required to have the ability to follow the deformation of the fabric.

In particular, in the pigment dispersant of Patent Document 1 and the aqueous pigment composition of Patent Document 2, the aromatic ring concentration in the polyurethane resin is high, so the cohesive force becomes high and the resin becomes hard. As a result, there is a problem that the ability to follow the deformation of the fabric is reduced.

Furthermore, ink compositions containing resin are required to have storage stability.

In particular, in the pigment dispersant of Patent Document 1 and the aqueous pigment composition of Patent Document 2, the polyester polyol obtained by reacting isophthalic acid and a polyol is hydrolyzed, so there is a problem that storage stability is reduced.

An object of the present invention is to provide a polyurethane dispersion that has excellent color development and adhesion when printing a fabric, has excellent followability to fabric deformation, and has excellent storage stability.

The present invention [1] is a polyurethane dispersion formed by dispersing a polyurethane resin in water, wherein the polyurethane resin is a reaction product of an isocyanate group-terminated prepolymer and a chain extender, and the polyurethane resin is a reaction product of an isocyanate group-terminated prepolymer and a chain extender. The polymer is a reaction product of a polyisocyanate component and a polyol component containing a macropolyol and a hydrophilic group-containing active hydrogen compound, the macropolyol includes an aromatic ring-containing macropolyol, and the aromatic ring-containing macropolyol is The alkylene oxide adduct of the compound having a bisphenol skeleton is included, and the amount of alkylene oxide added in the alkylene oxide adduct of the compound having a bisphenol skeleton is 2 mol or more and 10 mol or less with respect to 1 mol of the bisphenol skeleton, and the polyurethane The acid value of the resin is 7.0 mgKOH/g or more and 14.0 mgKOH/g or less, the total of the urethane group concentration and urea group concentration of the polyurethane resin is 20% by mass or less, and the aromatic ring in the polyurethane resin is A polyurethane dispersion having a concentration of 5.0% by mass or more and 15.0% by mass or less.

The present invention [2] includes the polyurethane dispersion described in the above [1], in which the polyisocyanate component contains an alicyclic polyisocyanate.

The present invention [3] includes the polyurethane dispersion according to the above [1] or [2], wherein the hydrophilic group-containing active hydrogen compound is an anionic group-containing active hydrogen compound.

The present invention [4] includes the polyurethane dispersion according to any one of [1] to [3] above, wherein the polyurethane dispersion has a dry elongation at break of 350% or more.

In the polyurethane dispersion of the present invention, the acid value of the polyurethane resin is 7.0 mgKOH/g or more and 14.0 mgKOH/g or less. When the acid value is 7.0 mgKOH/g or more, color development is excellent when printing a fabric. Further, when the acid value is 14.0 mgKOH/g or less, excellent adhesion is achieved when printing a fabric.

Further, in this polyurethane dispersion, the total of the urethane group concentration and urea group concentration of the polyurethane resin is 20.0% by mass or less. When the sum of the urethane group concentration and the urea group concentration is 20.0% by mass or less, the followability to the deformation of the fabric is excellent when printing the fabric.

Further, in this polyurethane dispersion, the aromatic ring concentration of the polyurethane resin is 5.0% by mass or more and 15.0% by mass or less. When the aromatic ring concentration is 5.0% by mass or more, color development and adhesion are excellent. Further, if the aromatic ring concentration is 15.0% by mass or less, the fabric can be excellent in followability to deformation.

Further, in this polyurethane dispersion, the aromatic ring-containing macropolyol includes an alkylene oxide adduct of a compound having a bisphenol skeleton. Therefore, it has excellent storage stability. Further, the amount of alkylene oxide added to the alkylene oxide adduct of the compound having a bisphenol skeleton is 2 mol or more and 10 mol or less with respect to 1 mol of the bisphenol skeleton. When the amount of alkylene oxide added is 2 moles or more, the ability to follow the deformation of the fabric is excellent. Moreover, if the amount of alkylene oxide added is 10 moles or less, the color development and adhesion are excellent.

FIGS. 1A to 1C show schematic diagrams of printed fabrics (printed articles). FIG. 1A shows a printed product that has excellent color development but poor adhesion. FIG. 1B shows a printed product that has excellent adhesion but poor color development. FIG. 1C shows a printed product that achieves both color development and adhesion.

Polyurethane dispersion is made by dispersing polyurethane resin in water.

Polyurethane resins are the reaction products of isocyanate group-terminated prepolymers and chain extenders.

<Isocyanate group-terminated prepolymer>
The isocyanate group-terminated prepolymer is a reaction product of a polyisocyanate component and a polyol component containing a macropolyol and a hydrophilic group-containing active hydrogen compound.

[Polyisocyanate component]
The polyisocyanate component includes a polyisocyanate and/or a derivative of a polyisocyanate.

(Polyisocyanate)
Examples of the polyisocyanate include aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, and araliphatic polyisocyanate.

Examples of aliphatic polyisocyanates include aliphatic diisocyanates. Examples of aliphatic diisocyanates include 1,6-hexamethylene diisocyanate (1,6-HDI), 1,5-pentamethylene diisocyanate (1,5-PDI), tetramethylene diisocyanate, trimethylene diisocyanate, 1,2- , 2,3- or 1,3-butylene diisocyanate, and 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate. Preferred aliphatic polyisocyanates include 1,6-HDI and 1,5-PDI.

Examples of alicyclic polyisocyanates include alicyclic diisocyanates. Examples of the alicyclic diisocyanate include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 4,4'-, 2,4'- or 2,2'-methylenebis( cyclohexyl isocyanate) or mixtures thereof (H ₁₂ MDI), 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane or mixtures thereof (H ₆ XDI), bis(isocyanatomethyl)norbornane (NBDI), 1, Examples include 3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, and methyl-2,6-cyclohexane diisocyanate. Preferred examples of the alicyclic polyisocyanate include IPDI, H ₁₂ MDI, and H ₆ XDI (preferably 1,3-H ₆ XDI).

Examples of aromatic polyisocyanates include aromatic diisocyanates. Aromatic diisocyanates include, for example, 4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate or a mixture thereof (MDI), 2,4- or 2,6-tolylene diisocyanate or its (TDI), o-tolidine diisocyanate, 1,5-naphthalene diisocyanate (NDI), m- or p-phenylene diisocyanate or mixtures thereof, 4,4'-diphenyl diisocyanate, and 4,4'-diphenyl ether diisocyanate. It will be done.

Examples of the araliphatic polyisocyanate include araliphatic diisocyanates. As the araliphatic diisocyanate, xylylene diisocyanate (1,2-, 1,3- or 1,4-xylylene diisocyanate or a mixture thereof) (XDI), 1,3- or 1,4-tetramethylxylylene diisocyanate or a mixture thereof (TMXDI), and ω,ω'-diisocyanate-1,4-diethylbenzene. Preferable examples of the araliphatic polyisocyanate include XDI.

Preferable examples of the polyisocyanate include aliphatic polyisocyanates, alicyclic polyisocyanates, and araliphatic polyisocyanates. From the viewpoint of improving the filterability of the polyurethane dispersion, more preferred examples of the polyisocyanate include alicyclic polyisocyanates.

Polyisocyanates can be used alone or in combination of two or more.

(Derivative of polyisocyanate)
Examples of polyisocyanate derivatives include the above-mentioned polyisocyanate multimers, allophanate derivatives, polyol derivatives, biuret derivatives, urea derivatives, oxadiazinetrione derivatives, carbodiimide derivatives, uretdione derivatives, and uretonimine derivatives.

The polyisocyanate derivatives can be used alone or in combination of two or more.

The polyisocyanate component preferably does not contain any derivatives of polyisocyanate and consists of polyisocyanate. The polyisocyanate component more preferably consists of an alicyclic polyisocyanate.

[Polyol component]
The polyol component includes a macropolyol and a hydrophilic group-containing active hydrogen compound.

(macropolyol)
The macropolyol includes an aromatic ring-containing macropolyol.

The aromatic ring-containing macropolyol includes an alkylene oxide adduct of a compound having a bisphenol skeleton. Therefore, it has excellent storage stability.

In the alkylene oxide adduct of a compound having a bisphenol skeleton, examples of the compound having a bisphenol skeleton include bisphenol A, bisphenol F, and bisphenol S. Preferable examples of the compound having a bisphenol skeleton include bisphenol A.

Examples of alkylene oxide adducts of compounds having a bisphenol skeleton include ethylene oxide adducts of compounds having a bisphenol skeleton and propylene oxide adducts of compounds having a bisphenol skeleton.

Preferred alkylene oxide adducts of such compounds having a bisphenol skeleton include ethylene oxide adducts of bisphenol A and propylene oxide adducts of bisphenol A.

In the alkylene oxide adduct of a compound having a bisphenol skeleton, the amount of alkylene oxide added in the alkylene oxide adduct of a compound having a bisphenol skeleton is 2 mol or more, preferably 4 mol or more, and 10 It is not more than 8 mol, preferably not more than 8 mol.

If the amount of alkylene oxide added is equal to or greater than the lower limit, the ability to follow deformation of the fabric (described later) will be improved.

On the other hand, if the amount of alkylene oxide added is less than the lower limit, it will be difficult to synthesize the urethane resin.

Further, if the amount of alkylene oxide added is below the above upper limit, the adhesion and color development will be improved.

On the other hand, if the amount of alkylene oxide added exceeds the above upper limit, the adhesion and color development will decrease.

The alkylene oxide adducts of compounds having a bisphenol skeleton can be used alone or in combination of two or more.

The content ratio of the alkylene oxide adduct of the compound having a bisphenol skeleton is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and even more preferably is 30 parts by mass or more, and for example, 97 parts by mass or less, preferably 90 parts by mass or less, more preferably 70 parts by mass or less, still more preferably 55 parts by mass or less, particularly preferably 40 parts by mass or less. It is.

Further, the content ratio of the alkylene oxide adduct of the compound having a bisphenol skeleton is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, more preferably 25 parts by mass or more, based on 100 parts by mass of the macropolyol. More preferably, 30 parts by mass or more, and for example, 100 parts by mass or less, preferably 90 parts by mass or less, more preferably 70 parts by mass or less, still more preferably 60 parts by mass or less, particularly preferably 50 parts by mass. parts, most preferably 40 parts by mass or less.

The aromatic ring-containing macropolyol can also contain other aromatic ring-containing macropolyols.

Other aromatic ring-containing macropolyols are compounds that have a hydroxyl group at the molecular end and have a number average molecular weight of 400 or more, preferably 500 or more, and 10,000 or less, preferably 5,000 or less, more preferably 3,000 or less. .

The average number of functional groups of the other aromatic ring-containing macropolyols is not particularly limited, but is preferably two.

Other aromatic ring-containing macropolyols include, for example, aromatic ring-containing polyester polyols, aromatic ring-containing polyether polyols, aromatic ring-containing polycarbonate polyols, aromatic ring-containing polyurethane polyols, aromatic ring-containing epoxy polyols, aromatic ring-containing polyolefin polyols, Examples include ring-containing acrylic polyols and aromatic ring-containing vinyl monomer-modified polyols.

The content ratio of the other aromatic ring-containing macropolyol is, for example, 10% by mass or less, preferably 5% by mass or less, more preferably 1% by mass or less, based on the aromatic ring-containing macropolyol.

The aromatic ring-containing macropolyol preferably does not contain any other aromatic ring-containing macropolyol and consists of an alkylene oxide adduct of a compound having a bisphenol skeleton.

In particular, the aromatic ring-containing macropolyol does not substantially contain aromatic ring-containing polyester polyol from the viewpoint of storage stability.

The aromatic ring-containing macropolyol does not substantially contain an aromatic ring-containing polyester polyol when the content of the aromatic ring-containing polyester polyol is, for example, 10% by mass or less, preferably 10% by mass or less, based on the aromatic ring-containing macropolyol. , 5% by mass or less, more preferably 1% by mass or less, even more preferably 0% by mass or less.

The macropolyol can also include an aromatic ring-free macropolyol.

The aromatic ring-free macropolyol is a compound having a hydroxyl group at the molecular end and having a number average molecular weight of 400 or more, preferably 500 or more, and 10,000 or less, preferably 5,000 or less, more preferably 3,000 or less.

The average number of functional groups of the aromatic ring-free macropolyol is not particularly limited, but is preferably two.

Examples of aromatic ring-free macropolyols include aromatic ring-free polyester polyols, aromatic ring-free polyether polyols, aromatic ring-free polycarbonate polyols, aromatic ring-free polyurethane polyols, aromatic ring-free epoxy polyols, and aromatic ring-free polyester polyols. Examples include polyolefin polyols, aromatic ring-free acrylic polyols, and aromatic ring-free vinyl monomer-modified polyols. Preferable examples of the aromatic ring-free macropolyol include aromatic ring-free polyether polyols and aromatic ring-free polycarbonate polyols.

Examples of aromatic ring-free polyether polyols include polyoxyalkylene (having 2 to 3 carbon atoms) polyols and polytetramethylene ether polyols.

Examples of polyoxyalkylene (having 2 to 3 carbon atoms) polyols include low molecular weight polyols described below and addition polymers of alkylene oxides having 2 to 3 carbon atoms using known low molecular weight polyamines as initiators. .

Examples of the alkylene oxide having 2 to 3 carbon atoms include propylene oxide and ethylene oxide. Further, these alkylene oxides can be used alone or in combination of two or more.

Specific examples of polyoxyalkylene (having 2 to 3 carbon atoms) polyols include polyoxyethylene glycol, polyoxypropylene glycol, and random and/or block copolymers of propylene oxide and ethylene oxide.

Further, the polyoxyalkylene (having 2 to 3 carbon atoms) polyol further includes polytrimethylene ether glycol.

Examples of polytrimethylene ether glycols include glycols obtained by polycondensation reaction of 1,3-propanediol derived from plant components.

Examples of polytetramethylene ether polyols include ring-opening polymers obtained by cationic polymerization of tetrahydrofuran (polytetramethylene ether glycol (crystalline)), polymer units such as tetrahydrofuran, and alkyl-substituted tetrahydrofuran and the above-mentioned divalent polymers. Examples include amorphous (non-crystalline) polytetramethylene ether glycol copolymerized with alcohol.

Preferred examples of the aromatic ring-free polyether polyol include polytetramethylene ether polyol. A more preferred example of the aromatic ring-free polyether polyol is polytetramethylene ether glycol.

Examples of aromatic ring-free polycarbonate polyols include aromatic ring-free polycarbonate diols. Examples of aromatic ring-free polycarbonate diols include ring-opening polymers of ethylene carbonate using a low molecular weight polyol (preferably dihydric alcohol) as an initiator, and dihydric alcohols (such as 1,4-butane) as described below. Examples include polycarbonate diols obtained by copolymerizing diols (1,5-pentanediol, 3-methyl-1,5-pentanediol, and 1,6-hexanediol) and ring-opening polymers.

The aromatic ring-free macropolyols can be used alone or in combination of two or more.

The blending ratio of the aromatic ring-free macropolyol is, for example, 40 parts by mass or more, preferably 45 parts by mass or more, more preferably 50 parts by mass or more, still more preferably 60 parts by mass, based on 100 parts by mass of the macropolyol. parts or more, and for example, 90 parts by mass or less, preferably 80 parts by mass or less, and more preferably 70 parts by mass or less.

Moreover, from the viewpoint of storage stability, the aromatic ring-free macropolyol preferably does not substantially contain aromatic ring-free polyester polyol.

The aromatic ring-free macropolyol does not substantially contain an aromatic ring-free polyester polyol when the content of the aromatic ring-free polyester polyol is, for example, 10% by mass or less, preferably 10% by mass or less, based on the macropolyol. , 5% by mass or less, more preferably 1% by mass or less, even more preferably 0% by mass or less.

That is, from the viewpoint of storage stability, the macropolyol does not substantially contain polyester polyols (aromatic ring-containing polyester polyols and aromatic ring-free polyester polyols).

The macropolyol is substantially free of polyester polyol when the content of the polyester polyol is, for example, 10% by mass or less, preferably 5% by mass or less, more preferably 1% by mass, based on the macropolyol. % or less, more preferably 0 mass % or less.

(Hydrophilic group-containing active hydrogen compound)
A hydrophilic group-containing active hydrogen compound is a compound containing a hydrophilic group and two or more active hydrogen groups. In addition, examples of the active hydrogen group include a hydroxyl group and an amino group.

Further, examples of the hydrophilic group include a nonionic group and an ionic group. More specifically, the hydrophilic group-containing active hydrogen compound includes, for example, an active hydrogen group-containing compound containing a nonionic group and an active hydrogen group-containing compound containing an ionic group.

An active hydrogen group-containing compound containing a nonionic group is a compound having both one or more nonionic groups and two or more active hydrogen groups. Examples of nonionic groups include polyoxyethylene groups. Examples of the active hydrogen group-containing compound containing a nonionic group include polyoxyethylene glycol, one end-capped polyoxyethylene glycol, and polyol containing a polyoxyethylene side chain.

Examples of the active hydrogen group-containing compound containing an ionic group include an active hydrogen group-containing compound containing an anionic group and an active hydrogen group-containing compound containing a cationic group.

An active hydrogen group-containing compound containing an anionic group is a compound having both one or more anionic groups and two or more active hydrogen groups. Examples of the anionic group include a carboxy group (carboxylic acid group) and a sulfo group (sulfonic acid group), and preferably a carboxy group. Furthermore, in the active hydrogen group-containing compound containing an anionic group, examples of the active hydrogen group include a hydroxyl group and an amino group, and preferably a hydroxyl group. That is, the active hydrogen group-containing compound containing an anionic group is preferably an organic compound having both a carboxyl group and two hydroxyl groups.

Examples of the organic compound having both a carboxyl group and two hydroxyl groups include carboxyl group-containing polyols. Examples of carboxyl group-containing polyols include polyhydroxyalkanoic acids. Examples of polyhydroxyalkanoic acids include 2,2-dimethylol acetic acid, 2,2-dimethylol lactic acid, 2,2-dimethylol propionic acid (also known as dimethylol propionic acid), 2,2-dimethylol butanoic acid, and 2,2-dimethylol propionic acid. -dimethylolbutyric acid and 2,2-dimethylolvaleric acid. Preferable examples of the organic compound having both a carboxyl group and two hydroxyl groups include 2,2-dimethylolpropionic acid.

An active hydrogen group-containing compound containing a cationic group is a compound having both one or more cationic groups and two or more active hydrogen groups. Examples of the cationic group include tertiary amino groups (tertiary amines capable of forming tertiary ammonium salts). Furthermore, in the active hydrogen group-containing compound containing a cationic group, examples of the active hydrogen group include a hydroxyl group and an amino group, and preferably a hydroxyl group. That is, the active hydrogen group-containing compound containing a cationic group is preferably an organic compound having both a tertiary amino group and two hydroxyl groups.

Examples of the organic compound having both a tertiary amino group and two hydroxyl groups include N-alkyl dialkanolamine. Examples of the N-alkyl dialkanolamine include N-methyldiethanolamine, N-propyldiethanolamine, N-butyldiethanolamine and N-methyldipropanolamine.

The hydrophilic group-containing active hydrogen compound preferably includes an active hydrogen group-containing compound containing an ionic group. More preferably, active hydrogen group-containing compounds containing anionic groups are used from the viewpoint of controlling the acid value of the polyurethane resin described below within a predetermined range.

The hydrophilic group-containing active hydrogen compounds can be used alone or in combination of two or more.

The blending ratio of the hydrophilic group-containing active hydrogen compound is, for example, 1 part by mass or more, preferably 2 parts by mass or more, more preferably 3 parts by mass or more, based on 100 parts by mass of the total amount of the polyol component. It is 10 parts by mass or less, preferably 5 parts by mass or less.

In particular, when the hydrophilic group-containing active hydrogen compound is an active hydrogen group-containing compound containing an anionic group (preferably a carboxy group), the above-mentioned blending ratio is within the above-mentioned range, and as described below. The acid value of the polyurethane resin can be set within a predetermined range.

(Low molecular weight polyol)
Moreover, the polyol component can also contain a low molecular weight polyol (low molecular weight polyol excluding a hydrophilic group-containing active hydrogen compound).

The low molecular weight polyol is a compound having a number average molecular weight of 40 or more and less than 400, preferably 300 or less.

The functional group of the low molecular weight polyol is, for example, preferably 2, although it is not particularly limited.

Examples of the low molecular weight polyol include diols having 2 to 6 carbon atoms and other low molecular weight polyols (excluding diols having 2 to 6 carbon atoms).

The diol having 2 to 6 carbon atoms is a compound having 2 to 6 carbon atoms having a number average molecular weight of 40 or more and less than 400, preferably 300 or less, and having two hydroxyl groups, such as an alkanediol having 2 to 6 carbon atoms. (alkylene glycol having 2 to 6 carbon atoms), ether diol having 2 to 6 carbon atoms, and alkenediol having 2 to 6 carbon atoms.

Examples of the alkanediol having 2 to 6 carbon atoms include ethylene glycol, propylene glycol (1,2- or 1,3-propanediol or a mixture thereof), butylene glycol (1,2- or 1,3- or 1, 4-butanediol or mixtures thereof), 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and 1,3- or 1,4-cyclohexane Examples include diols.

Examples of the ether diol having 2 to 6 carbon atoms include diethylene glycol, triethylene glycol, and dipropylene glycol, with triethylene glycol being preferred. Preferred examples of the ether diol having 2 to 6 carbon atoms include triethylene glycol.

Examples of the alkenediol having 2 to 6 carbon atoms include 1,4-dihydroxy-2-butene.

Other low molecular weight polyols are compounds having a number average molecular weight of 40 or more and less than 400, preferably 300 or less, and having two or more hydroxyl groups in one molecule, such as diols having 7 or more carbon atoms (dihydric alcohols). ), and trivalent or higher-valent low molecular weight polyols.

A diol (dihydric alcohol) having 7 or more carbon atoms is a compound having 7 or more carbon atoms, which has a number average molecular weight of 40 or more and less than 400, preferably 300 or less, and has two hydroxyl groups in one molecule, for example, Alkane-1,2-diol having 7 to 20 carbon atoms, 2,6-dimethyl-1-octene-3,8-diol, 1,3- or 1,4-cyclohexanedimethanol and mixtures thereof, hydrogenated bisphenols A, and bisphenol A.

Examples of diols (dihydric alcohols) having 7 or more carbon atoms include divalent polyalkylene oxides having a number average molecular weight of less than 400, preferably 300 or less. Such polyalkylene oxides can be produced, for example, by addition-reacting alkylene oxides such as ethylene oxide and/or propylene oxide using the above-mentioned dihydric alcohol as an initiator. (polyoxypropylene ether glycol), polyethylene polypropylene glycol (random or block copolymer), etc. Also included are polytetramethylene ether glycols having a number average molecular weight of less than 400, preferably 300 or less, obtained by ring-opening polymerization of tetrahydrofuran.

The low molecular weight polyol having a valence of 3 or more is a compound having a number average molecular weight of 40 or more and less than 400, preferably 300 or less, and having 3 or more hydroxyl groups in one molecule, such as a trihydric alcohol (low molecular weight triol). , tetrahydric alcohol, pentahydric alcohol, hexahydric alcohol, heptahydric alcohol, and octahydric alcohol. Examples of the trihydric alcohol include glycerin, 2-methyl-2-hydroxymethyl-1,3-propanediol, 2,4-dihydroxy-3-hydroxymethylpentane, 1,2,6-hexanetriol, and trimethylolpropane. , and 2,2-bis(hydroxymethyl)-3-butanol. Examples of the tetrahydric alcohol include tetramethylolmethane (pentaerythritol) and diglycerin. Examples of the pentahydric alcohol include xylitol. Examples of the hexahydric alcohol include sorbitol, mannitol, allitol, iditol, dulcitol, altritol, inositol, and dipentaerythritol. Examples of the heptahydric alcohol include perseitol. Examples of the octahydric alcohol include sucrose.

Furthermore, examples of the trivalent or higher molecular weight polyol include trivalent or higher polyalkylene oxides having a number average molecular weight of 40 or more and less than 400, preferably 300 or less. Such a polyalkylene oxide can be produced by adding an alkylene oxide such as ethylene oxide and/or propylene oxide to a polyethylene polyol using, for example, the above-mentioned trivalent or higher low molecular weight polyol or a known polyamine as an initiator. , polypropylene polyol, polyethylene polypropylene polyol (random or block copolymer).

Low molecular weight polyols can be used alone or in combination of two or more types.

The blending ratio of the low molecular weight polyol is, for example, 1 part by mass or more, preferably 5 parts by mass or more, and, for example, 15 parts by mass or less, based on 100 parts by mass of the total amount of polyol components.

The polyol component preferably does not contain a low molecular weight polyol and consists of a macropolyol and a hydrophilic group-containing active hydrogen compound.

[Preparation of isocyanate group-terminated prepolymer]
The isocyanate group-terminated prepolymer is obtained by reacting a polyisocyanate component and a polyol component.

As a method for reacting the polyisocyanate component and the polyol component, a known polymerization method (for example, bulk polymerization or solution polymerization) is selected, and solution polymerization is preferably used from the viewpoint of easier adjustment of reactivity and viscosity. selected.

In solution polymerization, for example, the above components are mixed into an organic solvent (solvent) and reacted under a nitrogen atmosphere.

In this reaction, the equivalent ratio (isocyanate group/active hydrogen group) of the isocyanate group in the polyisocyanate component to the active hydrogen group (hydroxyl group and/or amino group) in the polyol component exceeds 1, for example, 1.2. Above, preferably 1.3 or more, for example, 3.0 or less, preferably 2.5 or less. The terminal functional group of the reaction product obtained in such cases is an isocyanate group. In other words, an isocyanate group-terminated prepolymer is obtained.

As for the reaction conditions, the reaction temperature is, for example, 20°C or higher and, for example, 110°C or lower. Further, the reaction time is 1 hour or more and, for example, 20 hours or less.

Examples of the organic solvent include those that are inert to isocyanate groups and highly hydrophilic, such as acetone, methyl ethyl ketone, ethyl acetate, tetrahydrofuran, acetonitrile, and N-methylpyrrolidone. Preferably, the organic solvent is acetonitrile.

Further, in the above polymerization, for example, a reaction catalyst (eg, amine type, tin type, and lead type) may be added as necessary.

Furthermore, in the above reaction, unreacted polyisocyanate components and/or unreacted polyol components can also be removed by known methods such as distillation and extraction.

As a result, an isocyanate group-terminated prepolymer which is a reaction product of a polyisocyanate component and a polyol component is obtained.

In addition, when the polyisocyanate component and the polyol component are reacted by solution polymerization, the isocyanate group-terminated prepolymer is obtained as a reaction liquid containing the isocyanate group-terminated prepolymer and an organic solvent.

The isocyanate group-terminated prepolymer is a polyurethane prepolymer having at least one (preferably a plurality of, more preferably two) free isocyanate groups at its molecular end. The content of isocyanate groups (isocyanate group content in terms of solid content excluding solvent, i.e., isocyanate group concentration) is, for example, 0.5% by mass or more, preferably 1.0% by mass or more, and, for example, It is 5.0% by mass or less, preferably 4.0% by mass or less.

Further, when the reaction product contains an ionic group, preferably a neutralizing agent is added to neutralize it to form a salt of the ionic group.

As the neutralizing agent, when the ionic group is an anionic group, a commonly used base is employed. Commonly used bases include, for example, ammonia, amine compounds having 1 to 20 carbon atoms, or alkali metal hydroxides (eg, sodium hydroxide, potassium hydroxide, lithium hydroxide, etc.). Examples of amine compounds having 1 to 20 carbon atoms include primary amines such as monomethylamine, monoethylamine, monobutylamine, and monoethanolamine, such as dimethylamine, diethylamine, dibutylamine, diethanolamine, diisopropanolamine, and methylpropanolamine. secondary amines such as trimethylamine, triethylamine, dimethylethylamine, dimethylmonoethanolamine, triisopropanolamine, and tertiary amines such as triethanolamine. Moreover, when the ionic group is a cationic group, a commonly used acid is employed. Conventional acids include, for example, mono- or dicarboxylic acids having 1 to 7 carbon atoms, sulfonic acids having 1 to 20 carbon atoms, and inorganic acids. Examples of mono- or dicarboxylic acids having 1 to 7 carbon atoms include formic acid, acetic acid, propionic acid, oxalic acid and succinic acid. Examples of the sulfonic acid having 1 to 20 carbon atoms include methanesulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, trifluoromethanesulfonic acid and p-toluenesulfonic acid. Examples of inorganic acids include hydrochloric acid, sulfuric acid, and nitric acid.

In particular, when the ionic group is an anionic group (preferably a carboxy group), the neutralizing agent is used in an amount of 0.6 equivalent or more, preferably 0.8 equivalent or more per equivalent of the anionic group. It is added at a rate of, for example, 1.2 equivalents or less, preferably 1.1 equivalents or less.

<Chain extender>
Examples of chain extenders include the above-mentioned low molecular weight polyols and amino group-containing compounds.

Examples of amino group-containing compounds include aromatic polyamines, araliphatic polyamines, alicyclic polyamines, aliphatic polyamines, amino alcohols, polyoxyethylene group-containing polyamines, primary amino groups, or primary amino groups. and an alkoxysilyl compound having a secondary amino group, and hydrazine or a derivative thereof.

Examples of aromatic polyamines include 4,4'-diphenylmethanediamine and tolylenediamine.

Aroaliphatic polyamines include, for example, 1,3- or 1,4-xylylene diamines or mixtures thereof.

Examples of alicyclic polyamines include 3-aminomethyl-3,5,5-trimethylcyclohexylamine (also known as isophoronediamine), 4,4'-dicyclohexylmethanediamine, and 2,5(2,6)-bis( (aminomethyl)bicyclo[2.2.1]heptane, 1,4-cyclohexanediamine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis-(4-aminocyclohexyl)methane, diaminocyclohexane , 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5,5]undecane, 1,3- and 1,4-bis(aminomethyl)cyclohexane and mixtures thereof can be mentioned.

Examples of aliphatic polyamines include ethylenediamine, propylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexamethylenediamine, diethylenetriamine, triethylenetetramine, and tetraethylene. Pentamine and 1,3-diaminopentane are mentioned.

Examples of amino alcohols include 2-((2-aminoethyl)amino)ethanol (also known as N-(2-aminoethyl)ethanolamine) and 2-((2-aminoethyl)amino)-1- Examples include methylpropanol (also known as N-(2-aminoethyl)isopropanolamine).

Examples of polyoxyethylene group-containing polyamines include polyoxyalkylene ether diamines such as polyoxyethylene ether diamine. More specifically, examples include PEG #1000 diamine manufactured by NOF Corporation, and Jeffamine ED-2003, EDR-148, and XTJ-512 manufactured by Huntsman.

Examples of the alkoxysilyl compound having a primary amino group or a primary amino group and a secondary amino group include an alkoxysilyl compound having a primary amino group and a primary amino group and a secondary amino group. Examples include alkoxysilyl compounds having a class amino group. Examples of the alkoxysilyl compound having a primary amino group include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane. Examples of alkoxysilyl compounds having a primary amino group and a secondary amino group include N-β(aminoethyl)γ-aminopropyltrimethoxysilane (also known as N-2-(aminoethyl)-3-amino propyltrimethoxysilane), N-β(aminoethyl)γ-aminopropyltriethoxysilane (also known as: N-2-(aminoethyl)-3-aminopropyltriethoxysilane), N-β(aminoethyl)γ- Aminopropylmethyldimethoxysilane (alias: N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane) and N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane (alias: N-2- (aminoethyl)-3-aminopropylmethyldiethoxysilane).

Examples of hydrazine or its derivatives include hydrazine (including hydrazine monohydrate), succinic acid dihydrazide, sebacic acid dihydrazide, and adipic acid dihydrazide. Hydrazine or its derivative preferably includes hydrazine monohydrate.

Preferably, the chain extender is hydrazine or a derivative thereof.

Further, the chain extender can also be prepared, for example, as an aqueous solution (chain extender aqueous solution).

Chain extenders can be used alone or in combination of two or more.

<Preparation of polyurethane resin>
A polyurethane resin is obtained by reacting an isocyanate group-terminated prepolymer with a chain extender.

Specifically, an isocyanate group-terminated prepolymer and a chain extender are reacted, for example, in water to obtain a polyurethane resin (polyurethane dispersion).

In order to react the isocyanate group-terminated prepolymer and the chain extender in water, for example, first, the isocyanate group-terminated prepolymer is added to water to disperse the isocyanate group-terminated prepolymer in water, and then, A chain extender is added thereto, and the chain of the isocyanate group-terminated prepolymer is extended by the chain extender.

To disperse the isocyanate group-terminated prepolymer in water, water is mixed with isocyanate at a ratio of 50 to 1000 parts by weight of water (sometimes referred to as water-dispersed water) per 100 parts by weight of the isocyanate group-terminated prepolymer. Add the group-terminated prepolymer.

Thereafter, the chain extender is added to water in which the isocyanate group-terminated prepolymer is dispersed, while stirring. The mixture is added dropwise so that the ratio (hydrogen group/isocyanate group) is, for example, 0.8 or more and 1.2 or less.

After the dropwise addition of the chain extender is completed, the reaction is completed at room temperature, for example, with further stirring. The reaction time until the reaction is completed is, for example, 0.1 hour or more and, for example, 10 hours or less.

In addition, contrary to the above, water is added to the isocyanate group-terminated prepolymer to disperse the isocyanate group-terminated prepolymer in water, and then a chain extender is added thereto to chain the isocyanate group-terminated prepolymer. Chain elongation can also be carried out using an elongating agent.

Moreover, in this method, the organic solvent and water can be removed as necessary, and furthermore, water can be added to adjust the solid content concentration.

Thereby, the chain of the isocyanate group-terminated prepolymer is extended by the chain extender. Thereby, a polyurethane resin prepared as an aqueous dispersion (polyurethane dispersion) is obtained.

The acid value of the polyurethane resin is 7.0 mgKOH/g or more, preferably 8.0 mgKOH/g or more, more preferably 9.0 mgKOH/g or more, and 14.0 mgKOH/g or less, preferably 13.0 mgKOH /g or less, more preferably 11.0 mgKOH/g or less.

The acid value is adjusted within the above range, for example, by adjusting the blending ratio of the active hydrogen group-containing compound containing an anionic group (preferably a carboxy group).

If the acid value is equal to or higher than the lower limit, color development will be improved when printing a fabric (described later) (that is, color density will be high on the surface of the fabric (described later)).

On the other hand, if the acid value is less than the lower limit, color development will decrease when printing a fabric (described later).

Moreover, when the said acid value is below the said upper limit, when textile-printing a fabric (described later), adhesiveness will improve.

On the other hand, if the acid value exceeds the upper limit, adhesion will decrease when printing a fabric (described later).

The above acid value can be calculated from the charging ratio of the above components.

Further, the total of the urethane group concentration and urea group concentration of the polyurethane resin is 20.0% by mass or less, preferably 19.0% by mass or less, more preferably 17.0% by mass or less, still more preferably 16.0% by mass or less. 0% by mass or less, for example 5.0% by mass or more, preferably 10.0% by mass or more, more preferably 12.0% by mass or more, even more preferably 13.0% by mass or more, particularly preferably is 14.0% by mass or more, most preferably 15.0% by mass or more.

When the sum of the urethane group concentration and the urea group concentration is below the above upper limit, when printing a fabric (described later), the followability to deformation of the fabric (described later) and the texture are improved.

On the other hand, if the sum of the urethane group concentration and the urea group concentration exceeds the above upper limit, the followability to deformation of the fabric (described later) and the texture will decrease when printing the fabric (described later).

In addition, if the sum of the urethane group concentration and the urea group concentration is equal to or higher than the above lower limit, when printing a fabric (described later), color development, adhesion, and color transfer (for example, when printing a fabric after washing) This improves the suppression of color transfer (color transfer to other fabrics).

Note that the total of the urethane group concentration and the urea group concentration can be calculated from the charging ratio of the raw material components.

Further, the aromatic ring concentration in the polyurethane resin is 5.0% by mass or more, preferably 6.0% by mass or more, more preferably 8.0% by mass or more, still more preferably 10.0% by mass or more, Further, it is 15.0% by mass or less, preferably 12.0% by mass or less, more preferably 11.0% by mass or less.

When the above-mentioned aromatic ring concentration is equal to or higher than the above-mentioned lower limit, color development and adhesion are excellent when printing a fabric (described later).

On the other hand, if the aromatic ring concentration is less than the lower limit, color development and adhesion will decrease when printing a fabric (described later).

Moreover, when the aromatic ring concentration is below the above upper limit, when printing a fabric (described later), it is excellent in followability to deformation of the fabric (described later).

On the other hand, if the aromatic ring concentration exceeds the upper limit, the ability to follow the deformation of the fabric (described later) decreases when printing the fabric (described later).

The above aromatic ring concentration can be calculated from the charging ratio of raw material components.

The solid content concentration of the polyurethane dispersion is, for example, 10% by mass or more, preferably 20% by mass or more, and, for example, 50% by mass or less, preferably 40% by mass or less.

<Use of polyurethane dispersion>
A polyurethane dispersion is suitably used as a resin for dispersing a coloring material in an ink composition. Moreover, when the coloring material is a pigment, it is suitably used as a binder resin for physically fixing the pigment to the fabric.

The ink composition is a raw material for printing textiles.

Examples of the fabric include natural fibers and chemical fibers. Examples of natural fibers include cotton, silk, wool, and hemp. Examples of chemical fibers include polypropylene fibers, polyester fibers, and polyamide fibers.

When a polyurethane dispersion is used as a resin for dispersing a coloring material in an ink composition, the ink composition contains the coloring material and the polyurethane dispersion.

The coloring material is not particularly limited, and any known coloring material can be used.

A polyurethane dispersion is a component that disperses a coloring material in an ink composition.

The blending ratio of the polyurethane dispersion is, for example, 500 parts by mass or more and, for example, 1000 parts by mass or less, preferably 700 parts by mass or less, based on 100 parts by mass of the coloring material.

The ink composition is then prepared by mixing the coloring material and the polyurethane dispersion.

Further, the ink composition may contain known additives (for example, a humectant, a penetrant, a chelating agent, a preservative, and a pH adjuster), if necessary. That is, the ink composition contains known additives, if necessary. As the humectant, penetrant, chelating agent, preservative, and pH adjuster, those described in JP 2021-165353 A can be used.

The ink composition can also be diluted with water and/or an organic solvent (eg, ethylene glycol).

In addition, when a polyurethane dispersion is used as a binder resin for physically fixing a pigment to a fabric in an ink composition, the ink composition includes a pigment, the polyurethane dispersion, and, if necessary, a pigment dispersion. Contains liquid.

The pigment is not particularly limited, and any known pigment can be used.

A polyurethane dispersion is a binder resin for physically fixing a pigment to a fabric in an ink composition.

A pigment dispersion is a dispersant that disperses pigments.

The ink composition is prepared by mixing a pigment, a polyurethane dispersion, and, if necessary, a pigment dispersion.

Further, the above additives can also be added to the ink composition. The ink composition can also be diluted with water and/or an organic solvent (eg, ethylene glycol).

Next, a method for printing a fabric using this ink composition will be described in detail.

In order to print a fabric using an ink composition, the fabric is first pretreated. If the fabric is not pretreated, the interaction between the fabric and the ink composition will be weak, and the ink composition will soak into the fabric, resulting in poor color development. Particularly, when the fabric is a chemical fiber, the above-mentioned interaction is weaker than that of a natural fiber, so that the above-mentioned deterioration in color development becomes remarkable.

On the other hand, if the fabric is pretreated, the ink composition aggregates on the surface of the fabric due to the interaction between the fabric and the ink composition, thereby suppressing the penetration of the ink composition into the fabric. This improves color development.

To pre-treat the fabric, the fabric is treated with a pre-treatment agent.

Examples of the pretreatment agent include organic acids and their salts (eg, formic acid, sodium formate, acetic acid, and sodium acetate), polyvalent metal salts, and cationic compounds. Preferable examples of the pretreatment agent include organic acids. More preferred are acetic acid and sodium acetate. Pretreatment agents can also be prepared as aqueous solutions.

To treat a fabric with a pretreatment agent, the fabric is coated with the pretreatment agent. A known method (for example, a spray method) is selected as a method for applying the pretreatment agent to the fabric.

The ink composition is then applied to the fabric. As a method for applying the ink composition to the fabric, a known method (for example, a spray method, an inkjet method) is selected. This applies the ink composition to the fabric.

Next, the fabric (the fabric coated with the ink composition) is heated.

The heating temperature is, for example, 80°C or higher, preferably 100°C or higher, and, for example, 170°C or lower. Further, the heating time is, for example, 1 minute or more, preferably 5 minutes or more, and, for example, 60 minutes or less, preferably 30 minutes or less, and more preferably 15 minutes or less.

As a result, the fabric is printed (that is, a printed product is obtained).

Since the ink composition contains the above-mentioned polyurethane dispersion, it is possible to produce a printed article that has excellent color development and adhesion, and is excellent in followability to fabric deformation.

Further, the elongation at break of the dry product of the polyurethane dispersion is, for example, 300% or more, preferably 350% or more, more preferably 400% or more, and even more preferably, It is 450% or more, particularly preferably 500% or more.

Note that the method for measuring the elongation at break will be described in detail in Examples described later.

<Effect>
In the polyurethane dispersion, the acid value of the polyurethane resin, the sum of the urethane group concentration and urea group concentration of the polyurethane resin, and the aromatic ring concentration of the polyurethane resin are predetermined values. Therefore, when printing a fabric, it has excellent color development and adhesion, and is also excellent in following the deformation of the fabric.

On the other hand, color development and adhesion have a trade-off relationship.

Specifically, as shown in FIG. 1A, when printing the fabric 1, most of the polyurethane dispersion 2 (specifically, the ink composition containing the polyurethane dispersion 2) remains on the surface 3 of the fabric 1. Then, the color density becomes high on the surface 3 of the fabric 1, and the coloring property improves. On the other hand, in such a case, since the polyurethane dispersion 2 (specifically, the ink composition containing the polyurethane dispersion 2) has hardly permeated into the fabric 1, the fabric 1 and the polyurethane dispersion 2 ( Specifically, the adhesion with the ink composition (containing polyurethane dispersion 2) decreases.

Moreover, as shown in FIG. 1B, when most of the polyurethane dispersion 2 (specifically, the ink composition containing the polyurethane dispersion 2) permeates into the fabric 1, the adhesion improves. On the other hand, in such a case, since the polyurethane dispersion 2 (specifically, the ink composition containing the polyurethane dispersion 2) is hardly present on the surface 3 of the fabric 1, the coloring property is reduced.

Therefore, in order to achieve both color development and adhesion, it is necessary to use polyurethane dispersion 2 that remains on the surface 3 of fabric 1 (specifically, an ink composition containing polyurethane dispersion 2) and polyurethane that permeates into fabric 1. Dispersion 2 (specifically, an ink composition containing polyurethane dispersion 2) is considered. Specifically, as shown in FIG. 1C, while the polyurethane dispersion 2 (specifically, the ink composition containing the polyurethane dispersion 2) remains on the surface 3 of the fabric 1, and Adjust to the extent that it soaks into 3.

On the other hand, as shown in FIG. 1C, even if it is possible to achieve both color development and adhesion, if the polyurethane dispersion 2 remaining on the surface 3 of the fabric 1 becomes too hard, the ability to follow the fabric's deformation may deteriorate. decreases. In this case, the polyurethane dispersion 2 may peel off due to the deformation of the fabric.

In contrast, in this polyurethane dispersion, the acid value of the polyurethane resin, the sum of the urethane group concentration and urea group concentration of the polyurethane resin, the aromatic ring concentration of the polyurethane resin, and the alkylene oxide adduct of a compound having a bisphenol skeleton By adjusting the amount of alkylene oxide added to a predetermined value, it is possible to achieve both color development and adhesion, and to improve the ability to follow the deformation of the fabric.

Specifically, when the acid value of the polyurethane resin increases, the polyurethane dispersion (specifically, the polyurethane dispersion (ink compositions containing these) tend to aggregate. In this case, although color development can be improved, adhesion tends to decrease.

On the other hand, when the acid value of the polyurethane resin becomes low, the polyurethane dispersion (specifically, the ink composition containing the polyurethane dispersion) tends to aggregate due to interaction with the pretreatment agent (preferably formate ions) in the fabric. It becomes difficult to do. As a result, the polyurethane dispersion (specifically, the ink composition containing the polyurethane dispersion) easily permeates into the fabric. In this case, while adhesion can be improved, color development tends to decrease.

Since the acid value of this polyurethane dispersion is adjusted within a predetermined range, it is possible to achieve both color development and adhesion.

Furthermore, when the sum of the urethane group concentration and urea group concentration of the polyurethane resin becomes high, the polyurethane dispersion (specifically, the ink composition containing the polyurethane dispersion) tends to aggregate. As a result, the polyurethane dispersion (specifically, the ink composition containing the polyurethane dispersion) tends to remain on the surface of the fabric, and the polyurethane dispersion tends to become hard. In this case, the ability to follow the deformation of the fabric tends to decrease.

In this polyurethane dispersion, the sum of the urethane group concentration and urea group concentration of the polyurethane resin is adjusted to a predetermined value or less. Therefore, the ability to follow the deformation of the fabric can be improved.

Furthermore, as the aromatic ring concentration of the polyurethane resin increases, the cohesive force of the polyurethane dispersion (specifically, an ink composition containing the polyurethane dispersion) increases and tends to become hard. In this case, the ability to follow the deformation of the fabric tends to decrease.

On the other hand, when the aromatic ring concentration of the polyurethane resin decreases, the cohesive force of the polyurethane dispersion weakens, making it difficult for the ink composition containing the polyurethane dispersion to remain on the surface of the fabric, which tends to reduce color development and adhesion. be.

In this polyurethane dispersion, the aromatic ring concentration of the polyurethane resin is adjusted within a predetermined range. Therefore, color development and adhesion can be improved, and the ability to follow the deformation of the fabric can be improved.

In addition, in this polyurethane dispersion, the aromatic ring-containing macropolyol contains an alkylene oxide adduct of a compound having a bisphenol skeleton, and the amount of alkylene oxide addition of the alkylene oxide adduct of the compound having a bisphenol skeleton is per mole of the bisphenol skeleton. On the other hand, it is 2 mol or more and 10 mol or less. When the amount of alkylene oxide added is 2 moles or more, the ability to follow the deformation of the fabric is excellent. Moreover, if the amount of alkylene oxide added is 10 moles or less, the color development and adhesion are excellent.

In addition, in this polyurethane dispersion, the acid value of the polyurethane resin, the sum of the urethane group concentration and urea group concentration of the polyurethane resin, the aromatic ring concentration in the polyurethane resin, and the alkylene oxide of an alkylene oxide adduct of a compound having a bisphenol skeleton are determined. For ease of understanding, each added amount has been explained independently, but in reality, each does not have an effect independently, but they depend on each other and have a synergistic effect. It is something to do.

Further, in this polyurethane dispersion, the aromatic ring-containing macropolyol includes an alkylene oxide adduct of a compound having a bisphenol skeleton. Therefore, it has excellent storage stability.

Furthermore, when fabric is printed by ejecting droplets of the ink composition containing the polyurethane dispersion from a nozzle using an inkjet method, ejectability from the nozzle is required.

In this polyurethane dispersion, the acid value of the polyurethane resin, the sum of the urethane group concentration and urea group concentration of the polyurethane resin, and the aromatic ring concentration in the polyurethane resin are the above values, so the viscosity can be adjusted, and Clogging can be suppressed, and as a result, the ejection performance from the nozzle can be improved.

Specific numerical values such as blending ratios (content ratios), physical property values, parameters, etc. used in the following description are the corresponding blending ratios (content ratios) described in the above "Details of Carrying Out the Invention". ), physical property values, parameters, etc. can be replaced by the upper limit value (value defined as "less than" or "less than") or lower limit value (value defined as "more than" or "exceeding"). can. Furthermore, in the following description, unless otherwise specified, "parts" and "%" are based on mass.

<Ingredient details>
_1,3 -H ₆ ), trade name "Vestanat H ₁₂ MDI", Evonik HDI: hexamethylene diisocyanate, Tosoh Corporation PDI: 1,5-pentamethylene diisocyanate, trade name "Stabio PDI", Mitsui Chemicals XDI: 1,3- Xylylene diisocyanate, trade name "Takenate 500", Mitsui Chemicals TDI: Tolylene diisocyanate BPX-11: propylene oxide adduct of bisphenol A, propylene oxide addition amount of bisphenol A propylene oxide adduct, 2 mol of propylene oxide, manufactured by ADEKA BA- 2: Ethylene oxide adduct of bisphenol A, 2 moles of ethylene oxide added to the ethylene oxide adduct of bisphenol A, BA-4JU manufactured by Nippon Nyukazai Co., Ltd.: Ethylene oxide adduct of bisphenol A, ethylene oxide adduct of bisphenol A Added amount of oxide: 4 moles, Nippon Nyukazai Co., Ltd. BA-6U: Ethylene oxide adduct of bisphenol A, Added ethylene oxide amount of ethylene oxide adduct of bisphenol A: 6 moles, Nippon Nyukazai Co., Ltd. BA-8: Ethylene oxide of bisphenol A Adduct, 8 mol of ethylene oxide added to ethylene oxide adduct of bisphenol A, manufactured by Nippon Nyukazai BA-10: ethylene oxide adduct of bisphenol A, 10 mol of ethylene oxide added to ethylene oxide adduct of bisphenol A, Japan BPA-16 manufactured by Nyukazai Co., Ltd.: ethylene oxide adduct of bisphenol A, ethylene oxide addition amount of ethylene oxide adduct of bisphenol A 16 moles, PTMG-2000 manufactured by Nippon Nyukazai Co., Ltd.: polytetramethylene ether glycol, number average molecular weight 2000, Mitsubishi UH-200 manufactured by Chemical Co., Ltd.: UH-200: Polycarbonate diol, number average molecular weight 2000, 1,4-BG manufactured by Ube Industries, Ltd.: 1,4-butanediol, BA manufactured by Fuji Film Wako Pure Chemical Industries: Bisphenol A. Mitsubishi Chemical DMPA: 2,2-dimethylolpropionic acid, Perstorp TEA: triethylamine, Fuji Film Wako Pure Chemical Industries, Ltd. HYD・H ₂ O: hydrazine monohydrate, Fuji Film Wako Pure Chemical Industries, Ltd.

<Preparation of aromatic ring-containing polyester polyol>
Preparation example 1
Mix 330.6 g of isophthalic acid (IPA) and 402.5 g of sebacic acid (SbA) as polybasic acids with 72.8 g of ethylene glycol (EG) and 376.5 g of neopentyl glycol (NPG) as polyhydric alcohols. did. Then, 0.1 g of tin octylate (esterification catalyst) was added to the mixed solution, and the reaction temperature was adjusted to 180 to 220°C under a nitrogen stream to cause an esterification reaction between the polybasic acid and the low molecular weight polyol. Ta. Next, predetermined amounts of water and glycol were distilled off to prepare a polyester polyol. The hydroxyl value of the polyester polyol was 44.9 mgKOH/g. Further, the number average molecular weight (Mn) of the polyester polyol was 2,499.

Preparation example 2
An aromatic polyester polyol was synthesized according to Synthesis Example 2 described in JP-A-2015-174876. Specifically, while introducing nitrogen gas into a reactor equipped with a thermometer, a nitrogen gas introduction tube, and a stirrer, 42.1 parts by mass of isophthalic acid, 21.4 parts by mass of sebacic acid, and 9.3 parts by mass of adipic acid were introduced. 7.7 parts by mass of ethylene glycol, 25.8 parts by mass of neopentyl glycol, 11.2 parts by mass of butanediol, and 0.05 parts by mass of dibutyltin oxide and esterified at 180 to 230°C for 24 hours. A polycondensation reaction was carried out at 230°C for 24 hours until the acid value became 1 or less to obtain an aromatic polyester polyol (acid value 0.3, hydroxyl value 56.1, aromatic cyclic concentration 2.53 mol/kg). .

<Preparation of polyurethane dispersion>
Example 1
In a four-necked flask equipped with a stirrer, thermometer, reflux tube, and nitrogen introduction tube, 81.5 parts by mass of BPX-11, 8.4 parts by mass of DMPA (hydrophilic group-containing active hydrogen compound), and 79.2 parts of acetonitrile. The mass part was prepared. Next, 91.7 parts by mass of 1.3-H ₆ (A reaction solution containing an isocyanate group-terminated prepolymer) was obtained.

Next, 151.0 parts by mass of acetonitrile was added to this reaction solution, and after cooling to 30° C., 6.2 parts by mass of TEA (neutralizing agent) was added.

Next, while stirring was continued, 816.7 parts by mass of ion-exchanged water (water-dispersed water) was gradually added to water-disperse the isocyanate group-terminated prepolymer. In this way, an aqueous dispersion of the isocyanate group-terminated prepolymer was prepared.

Next, 4.5 parts by mass of HYD·H ₂ O was added to the aqueous dispersion of the isocyanate group-terminated prepolymer, and the mixture was reacted for 1 hour.

Next, acetonitrile was distilled off under reduced pressure at 50° C., and then ion-exchanged water was added to prepare a polyurethane dispersion (solid content: 30% by mass).

Examples 2 to 21 and Comparative Examples 1 to 9
Based on the same procedure as in Example 1, a polyurethane dispersion (solid content 30% by mass) was prepared. However, the formulation was changed according to Tables 1 to 4. In addition, in Comparative Example 9, gelation occurred during synthesis.

<Evaluation>
[Acid value]
The acid value of the polyurethane resin of each Example and each Comparative Example was calculated from the charging ratio of raw material components. The results are shown in Tables 1 to 4.

[Urethane group and urea group concentration]
The urethane group and urea group concentrations of the polyurethane resins of each Example and each Comparative Example were calculated from the charging ratio of the raw material components. The results are shown in Tables 1 to 4.

[Aromatic ring concentration]
The aromatic ring concentration of the polyurethane resin of each Example and each Comparative Example was calculated from the charging ratio of raw material components. The results are shown in Tables 1 to 4.

[Elongation at break]
The polyurethane dispersions (PUD) of each example and each comparative example were applied to a polypropylene tray to a dry thickness of 200 μm, dried at room temperature (25°C) for 1 day, and then heated at 110°C for 1 hour. A sample for physical property measurement was prepared. Using a tensile compression tester (Model 205N, manufactured by Intesco), a tensile test was performed at 23° C. and a tensile speed of 300 mm/min to determine the elongation at break (%). The results are shown in Tables 1 to 4.

[Color development]
Kanakin No. 3 (100% cotton) fabric was cut into 210 mm in length and 30 mm in width to prepare a fabric. Next, 4.5 g of acetic acid, 6.2 g of sodium acetate, and 89.3 g of water were mixed to prepare a pretreatment agent. Next, 34.3 g of polyurethane dispersion (solid content concentration 35% by mass) of each Example and each Comparative Example, coloring material (Daistone X Color Blue MX, manufactured by Matsui Shiki Kagaku Kogyo Co., Ltd., active ingredient 25% by mass)8. 0 g, 20.0 g of ethylene glycol, and 37.7 g of water were mixed to prepare an ink composition.

Next, about 1.2 g of pretreatment agent was applied to the fabric using a sprayer. Approximately 2 g of the ink composition was then applied to the fabric using a sprayer.

Thereafter, this fabric was heat treated at 110° C. for 10 minutes. As a result, a printed product was obtained.

The color development of the printed material was visually observed. Color development was evaluated using the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: A film was formed on the fabric, and the color development was significantly high.
3: A film was formed on the fabric, and the color development was slightly high.
2: The ink composition penetrated into the fabric, resulting in slightly low color development.
1: The ink composition penetrated into the fabric, resulting in significantly low color development.

[Adhesion]
Kanakin No. 3 was cut into pieces of 50 mm in length and 50 mm in width, and moistened with distilled water to be used as a white rubbing cloth. The printed material obtained in the color development test and the white rubbing cloth were tested as No. It was attached to a 428 Gakushin type abrasion tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd., Friction Tester Type II), and tested under a load of 200 g, a swing width of 100 mm, and a reciprocating cycle of 100 times (30 times/min). After the test, the adhesion of the ink layer to Kanakin No. 3 was visually observed for the printed product. Adhesion was evaluated using the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: The ink layer did not peel off, and all the ink film remained.
3: Part of the ink layer peeled off, but more than half of the ink film remained.
2: More than half of the ink layer has peeled off.
1: The ink layer was completely peeled off.

[Color transfer]
Regarding the white rubbing cloth obtained in the adhesion test, the L value (the higher the value, the whiter it is and the lower the degree of contamination) was measured using a spectrocolor meter (Spectro Color Meter 2000, Nippon Denshoku Industries Co., Ltd.). Note that the L value of the white friction cloth before the test was 90 or more. Color transfer was evaluated based on the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: L value was 90 or more, and no color transfer was observed.
3: Slight color transfer was observed when the L value was 85 or more and less than 90.
2: Color transfer was observed when the L value was 70 or more and less than 85.
1: Significant color transfer was observed when the L value was 70 or less.

[Texture]
The printed material obtained in the color development test was observed with a tentacle. The texture was evaluated using the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: It was flexible.
3: Slight flexibility was felt.
2: Slight hardness was felt.
1: It was hard.

[Followability]
A printed material was produced according to the method for producing the printed material obtained in the color development test, except that polyester flat rubber was used instead of Kanakin No. 3.

The obtained printed material was stretched 1.5 times in the warp direction and returned 10 times, and then the state of the ink layer was visually observed. Followability was evaluated using the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: No particular change was observed.
3: Lifting was observed in a part of the ink layer, but no cracking was observed.
2: Lifting and cracking were observed in a part of the ink layer.
1: Cracks were observed in most of the ink layer.

[Solvent dilution viscosity]
Distilled water was added to the polyurethane dispersion (solid content concentration 35% by mass) of each Example and each Comparative Example to adjust the solid content concentration to 20% by mass, and a viscometer (model TVB-25L, Toki The viscosity at 25° C. was measured using the following method (manufactured by Sangyo Co., Ltd.). Furthermore, the viscosity at 25° C. was measured in the same manner except that triethylene glycol was used instead of distilled water. The viscosity increase rate of the viscosity when prepared with triethylene glycol relative to the viscosity when prepared with distilled water was evaluated based on the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: Less than 2.0 times.
3: 2.0 times or more and less than 5.0 times.
2: 5.0 times or more and less than 10.0 times.
It was 1:10 times or more.

[Filterability of polyurethane dispersion (PUD filterability)]
20 g of the polyurethane dispersion (solid content concentration 35% by mass) of each Example and each Comparative Example was sucked up with a syringe, extruded with a syringe filter having a different hole diameter attached, and the filterability was evaluated using the following criteria. The results are shown in Tables 1 to 4.
{standard}
4: Passed all 0.8 μm.
3: Passed all 3 μm.
2: Passed all 5 μm.
1: Did not pass through 5 μm at all.

[Storage stability]
For each example and each comparative example in which color development and adhesion were evaluated as 3 or higher, the ink composition prepared in the color development test was stored at 60°C for 2 months, and printed materials were printed using the method described in the color development test. Created. The resulting printed fabric was evaluated for color development and adhesion. Storage stability was evaluated using the following criteria. The results are shown in Tables 1 to 4.
(standard)
O: Evaluation of color development and adhesion was 3 or more.
×: Evaluation of color development and adhesion was 2 or less.

Claims (4)

A polyurethane dispersion made by dispersing polyurethane resin in water,
The polyurethane resin is a reaction product of an isocyanate group-terminated prepolymer and a chain extender,
The isocyanate group-terminated prepolymer is a reaction product of a polyisocyanate component and a polyol component containing a macropolyol and a hydrophilic group-containing active hydrogen compound,
The macropolyol includes an aromatic ring-containing macropolyol,
The aromatic ring-containing macropolyol includes an alkylene oxide adduct of a compound having a bisphenol skeleton,
The amount of alkylene oxide added to the alkylene oxide adduct of the compound having a bisphenol skeleton is 2 mol or more and 10 mol or less per 1 mol of the bisphenol skeleton,
The acid value of the polyurethane resin is 7.0 mgKOH/g or more and 14.0 mgKOH/g or less,
The total of the urethane group concentration and urea group concentration of the polyurethane resin is 20% by mass or less,
A polyurethane dispersion in which the aromatic ring concentration in the polyurethane resin is 5.0% by mass or more and 15.0% by mass or less. The polyurethane dispersion according to claim 1, wherein the polyisocyanate component includes an alicyclic polyisocyanate. The polyurethane dispersion according to claim 1 or 2, wherein the hydrophilic group-containing active hydrogen compound is an anionic group-containing active hydrogen compound. The polyurethane dispersion according to any one of claims 1 to 3, wherein the polyurethane dispersion has a dry elongation at break of 350% or more.

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