Provided are processes of functionalizing a microparticle that include reacting a microparticle expressing a carboxylic acid with a functionalization linker including the structure N-L.sup.1-A where N is a free amine, L.sup.1 is a linker, and A is an azide and an alkyne terminated group, to form a functional group terminated microparticle, and forming a functionalized microparticle by reacting the functional group terminated microparticle with a peptide including a terminal functional group comprising an alkyne or azide, where the peptide includes the structure F-L.sup.2-Peptide, where F is a functional group and L.sup.2 is a linker. Also provided are compositions suitable for effectively coupling a peptide to a microsphere and functionalized microspheres suitable for reacting with a detection agent.

[Problems] To provide a reversibly thermochromic composition having excellent contrast between a colored state and a decolored state, and excellent light resistance, and a reversibly thermochromic microcapsule pigment encapsulating the reversibly thermochromic composition.

[Solution] Disclosed is a reversibly thermochromic composition including: (a) an electron-donating color-developing organic compound; (b) a combination of a compound having a specific structure as an electron-accepting compound; and (c) a reaction medium which reversibly induces an electron transfer reaction between the component (a) and the component (b) in a specific temperature range, and a reversibly thermochromic microcapsule pigment encapsulating the reversibly thermochromic composition.

A reactive dye of formula

##STR00001##

wherein M is hydrogen, an alkali metal or one equivalent of an alkaline earth metal, Z.sub.1 is vinyl, β-sulfatoethyl or the radical —NHCO—(CH.sub.2).sub.3—SO.sub.2—CH.sub.2CH.sub.2Cl; R.sub.1 denotes H or sulfo; and R.sub.2 is H, methyl, methoxy or sulfo, n is the number 3; Y is vinyl or a radical —CH.sub.2—CH.sub.2-U and U is —Cl or —OSO.sub.3H,
is suitable for dyeing and printing cellulosic or amide-group-containing fibre materials.

A reactive dye of formula ##STR00001##
wherein M is hydrogen, an alkali metal or one equivalent of an alkaline earth metal, Z.sub.1 is vinyl, ?-sulfatoethyl or the radical NHCO(CH.sub.2).sub.3SO.sub.2CH.sub.2CH.sub.2Cl; R.sub.1 denotes H or sulfo; and R.sub.2 is H, methyl, methoxy or sulfo, n is the number 3; Y is vinyl or a radical CH.sub.2CH.sub.2-U and U is Cl or OSO.sub.3H, is suitable for dyeing and printing cellulosic or amide-group-containing fibre materials.

Colorant compositions which are suitable for tinting base paint or stains in color tinting equipment and which provide improved resistance to microbial contamination by inclusion of a combination of antimicrobial agents. Also disclosed is a method for assessing the resistance of colorant compositions to microbial growth.

A mixture contains a compound having a specific structure and acting as a dye and a compound having a specific structure and acting as an ultraviolet light absorbent.

Colorant compositions which are suitable for tinting base paint or stains in color tinting equipment and which provide improved resistance to microbial contamination by inclusion of a combination of antimicrobial agents. Also disclosed is a method for assessing the resistance of colorant compositions to microbial growth.

Colorant compositions which are suitable for tinting base paint or stains in color tinting equipment and which provide improved resistance to microbial contamination by inclusion of a combination of antimicrobial agents. Also disclosed is a method for assessing the resistance of colorant compositions to microbial growth and tinted paints and stains that include the colorant compositions.