An object is to provide an ink composition for inkjet printing that permits inkjet printing, particularly on metal surfaces, wherein such ink composition possesses sufficiently high adhesion and heat resistance with respect to metal surfaces. As a means for achieving the object, a photocurable inkjet printing ink composition is provided, which contains, relative to the entire ink composition, 0.1 percent by mass or more of an acid-modified acrylic monomer and 10 to 30 percent by mass of a monofunctional monomer with a Tg of 100 C. or above, wherein the monofunctional monomer accounts for 80 percent by mass or more of all monomers.

An object is to provide an ink composition for inkjet printing that permits inkjet printing, particularly on metal surfaces, wherein such ink composition possesses sufficiently high adhesion and heat resistance with respect to metal surfaces. As a means for achieving the object, a photocurable inkjet printing ink composition is provided, which contains, relative to the entire ink composition, 0.1 percent by mass or more of an acid-modified acrylic monomer and 10 to 30 percent by mass of a monofunctional monomer with a Tg of 100 C. or above, wherein the monofunctional monomer accounts for 80 percent by mass or more of all monomers.

Provided is a zwitterionic polymer that has a zwitterion that includes an effect of improving the stability of proteins. This zwitterionic polymer is a polymeric protein stabilizer that exhibits a protein stabilizing effect even at a small addition amount of addition, and at the same time has an antioxidant capability. Also provided is a method for producing this zwitterionic polymer. This problem is solved by a zwitterionic polymer containing a repeating unit represented by formula (1) and having a number-average molecular weight of 1,000 to 1,000,000. On formula (1), R.sup.1 and R.sup.2 are each independently selected from a hydrogen atom; linear, branched or cyclic alkyl groups having 1 to 6 carbons; aromatic groups having 6 to 20 carbons; or alkylene groups having 1 to 6 carbons and formed by linking R.sup.1 to R.sup.2. R.sup.3 represents a hydrogen atom or a methyl group).

Provided is a zwitterionic polymer that has a zwitterion that includes an effect of improving the stability of proteins. This zwitterionic polymer is a polymeric protein stabilizer that exhibits a protein stabilizing effect even at a small addition amount of addition, and at the same time has an antioxidant capability. Also provided is a method for producing this zwitterionic polymer. This problem is solved by a zwitterionic polymer containing a repeating unit represented by formula (1) and having a number-average molecular weight of 1,000 to 1,000,000. On formula (1), R.sup.1 and R.sup.2 are each independently selected from a hydrogen atom; linear, branched or cyclic alkyl groups having 1 to 6 carbons; aromatic groups having 6 to 20 carbons; or alkylene groups having 1 to 6 carbons and formed by linking R.sup.1 to R.sup.2. R.sup.3 represents a hydrogen atom or a methyl group).

The present invention relates to a hydrated crystalline form of 2 -acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58, 11.2, 12.65, 13.66, 16.28, 18.45, 20, 20.4, 22.5, 25.5, 25.88, 26.47, 28.52, 30.28, 30.8, 34.09, 38.19, 40.69, 41.82, 43.74, 46.04 degrees (+/ 0.1.

The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

The present invention relates to a hydrated crystalline form of 2 -acrylamido-2-methylpropane sulfonic acid having a 2-theta powder X-ray diffraction diagram comprising peaks at 10.58, 11.2, 12.65, 13.66, 16.28, 18.45, 20, 20.4, 22.5, 25.5, 25.88, 26.47, 28.52, 30.28, 30.8, 34.09, 38.19, 40.69, 41.82, 43.74, 46.04 degrees (+/ 0.1.

The present invention also relates to a production method for this form of 2-acrylamido-2-methylpropane sulfonic acid and a preparation method for an aqueous solution A of a salt of this form of 2-acrylamido-2-methylpropane sulfonic acid, and the (co)polymer of this form of -acrylamido-2-methylpropane sulfonic acid.

A polymer compound for a conductive polymer contains one or more kinds of repeating units a represented by the following general formula (1) and has a weight average molecular weight in the range of 1,000 to 500,000, ##STR00001##
R.sup.1 represents a hydrogen atom or a methyl group; Rf.sub.1 represents a linear or branched alkyl group having 1 to 4 carbon atoms or a phenyl group, and has at least one fluorine atom or a trifluoromethyl group in Rf.sub.1; Z.sub.1 represents a single bond, an arylene group having 6 to 12 carbon atoms or C(O)OR.sup.2; R.sup.2 represents a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, an arylene group having 6 to 10 carbon atoms or an alkenylene group having 2 to 10 carbon atoms, and may have an ether group, a carbonyl group or an ester group in R.sup.2; and a is 0<a1.0.

A polymer compound for a conductive polymer contains one or more kinds of repeating units a represented by the following general formula (1) and has a weight average molecular weight in the range of 1,000 to 500,000, ##STR00001##
R.sup.1 represents a hydrogen atom or a methyl group; Rf.sub.1 represents a linear or branched alkyl group having 1 to 4 carbon atoms or a phenyl group, and has at least one fluorine atom or a trifluoromethyl group in Rf.sub.1; Z.sub.1 represents a single bond, an arylene group having 6 to 12 carbon atoms or C(O)OR.sup.2; R.sup.2 represents a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, an arylene group having 6 to 10 carbon atoms or an alkenylene group having 2 to 10 carbon atoms, and may have an ether group, a carbonyl group or an ester group in R.sup.2; and a is 0<a1.0.

A polymer compound having a weight average molecular weight in the range of 1,000 to 500,000, and contains one or more repeating units represented by formula (1) and one or more repeating units represented by formula (2):

##STR00001## R.sup.1 represents a hydrogen atom or a methyl group; Rf.sub.1 represents a linear or branched alkyl group having 1 to 4 carbon atoms or a phenyl group, and has at least one fluorine atom or a trifluoromethyl group in Rf.sub.1; Z.sub.1 represents a single bond, an arylene group having 6 to 12 carbon atoms or C(O)OR.sup.2; R.sup.2 represents a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, an arylene group having 6 to 10 carbon atoms or an alkenylene group having 2 to 10 carbon atoms, and may have an ether group, a carbonyl group or an ester group in R.sup.2; and a is 0<a1.0, and

##STR00002## b is 0<b<1.0.

A polymer compound having a weight average molecular weight in the range of 1,000 to 500,000, and contains one or more repeating units represented by formula (1) and one or more repeating units represented by formula (2):

##STR00001## R.sup.1 represents a hydrogen atom or a methyl group; Rf.sub.1 represents a linear or branched alkyl group having 1 to 4 carbon atoms or a phenyl group, and has at least one fluorine atom or a trifluoromethyl group in Rf.sub.1; Z.sub.1 represents a single bond, an arylene group having 6 to 12 carbon atoms or C(O)OR.sup.2; R.sup.2 represents a linear, branched or cyclic alkylene group having 1 to 12 carbon atoms, an arylene group having 6 to 10 carbon atoms or an alkenylene group having 2 to 10 carbon atoms, and may have an ether group, a carbonyl group or an ester group in R.sup.2; and a is 0<a1.0, and

##STR00002## b is 0<b<1.0.