[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.

[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.

An aspect of the present disclosure relates to a dispersant composition for an electrode of a power storage device. The dispersant composition contains an acrylic polymer (A), a compound (B) represented by the following formula (1), and an organic solvent (C). The acrylic polymer (A) contains a constitutional unit a represented by the following formula (3). In the formula (1), R.sup.1 represents a group represented by the following formula (2), and R.sup.2 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or —CH.sub.2CH.sub.2—OH. In the formula (2), R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are the same or different and represent a hydrogen atom, a methyl group, or —CH.sub.2OH.

##STR00001##

An aspect of the present disclosure relates to a dispersant composition for an electrode of a power storage device. The dispersant composition contains an acrylic polymer (A), a compound (B) represented by the following formula (1), and an organic solvent (C). The acrylic polymer (A) contains a constitutional unit a represented by the following formula (3). In the formula (1), R.sup.1 represents a group represented by the following formula (2), and R.sup.2 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or —CH.sub.2CH.sub.2—OH. In the formula (2), R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are the same or different and represent a hydrogen atom, a methyl group, or —CH.sub.2OH.

##STR00001##

Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (I):

##STR00001## wherein R.sub.1, and R.sub.2 are selected from a linear or branched alkyl group, alkenyl group, alkoxy group, aryl group and an alkylene aryl group having from 6 to 22 carbon atoms; X.sub.1 and X.sub.2 are selected from —OC(O)-, —CO.sub.2- and O; R.sub.3, R.sub.4 and R.sub.5 are selected from hydrogen and an linear or branched alkyl group, cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group; R.sub.6 is selected from hydrogen, R.sub.3, —X.sub.1R.sub.1 and aryl and halogen; Y.sub.1 Y.sub.2 Y.sub.3 and Y.sub.4 are selected from hydrogen, R.sub.3, —OR.sub.3 and halogen; a is 0 to 4; b is 0 or 1; x and y are independently is 0 or 1 provided that where x and y are 0, a is 0 and b is 1 and R.sub.6 is —CO.sub.2R.sub.1; and wherein when a is 0 and b is 1 and R.sub.5 or R.sub.6 is phenyl, R.sub.6 and R.sub.5 respectively are not hydrogen or C.sub.1-7 alkyl. The compounds are useful in ink compositions, writing implements containing the compound and medical and industrial applications in which temperature sensitive colour change may be required.

Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (I):

##STR00001## wherein R.sub.1, and R.sub.2 are selected from a linear or branched alkyl group, alkenyl group, alkoxy group, aryl group and an alkylene aryl group having from 6 to 22 carbon atoms; X.sub.1 and X.sub.2 are selected from —OC(O)-, —CO.sub.2- and O; R.sub.3, R.sub.4 and R.sub.5 are selected from hydrogen and an linear or branched alkyl group, cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group; R.sub.6 is selected from hydrogen, R.sub.3, —X.sub.1R.sub.1 and aryl and halogen; Y.sub.1 Y.sub.2 Y.sub.3 and Y.sub.4 are selected from hydrogen, R.sub.3, —OR.sub.3 and halogen; a is 0 to 4; b is 0 or 1; x and y are independently is 0 or 1 provided that where x and y are 0, a is 0 and b is 1 and R.sub.6 is —CO.sub.2R.sub.1; and wherein when a is 0 and b is 1 and R.sub.5 or R.sub.6 is phenyl, R.sub.6 and R.sub.5 respectively are not hydrogen or C.sub.1-7 alkyl. The compounds are useful in ink compositions, writing implements containing the compound and medical and industrial applications in which temperature sensitive colour change may be required.

A variety of particles forming microencapsulated thermochromic materials. The particles can include a thermochromic core and a metal oxide shell encapsulating the thermochromic core. The thermochromic core can include one or both of an organic thermochromic material and an inorganic salt thermochromic material. In some aspects, the particles include a dye selected from a crystal violet lactone dye, a fluoran dye, and a combination thereof. In still further aspects, the particles include a color developer selected from a hydroxybenzoate, a 4,4′-dihydroxydiphenyl propane, a hydroxycoumarin derivative, a lauryl gallate, and a combination thereof. In some aspects, the metal oxide shell is a TiO.sub.2 shell. The particles can be used in cements and paints and for a variety of building materials. Methods of making the particles and building materials and methods of use, for example, for removing a volatile organic carbon from a building material, are also provided.

The present disclosure is drawn to an electronic device housing that can include a heat sensitive coating and a second heat sensitive coating applied to an electronic device housing. The heat sensitive coating or portion thereof can include a thermochromatic colorant having a color-changing activation temperature, and the second heat sensitive coating or portion thereof can include a second thermochromatic colorant having a second color-changing activation temperature. The color-changing activation temperature can be a temperature from 30° C. to about 100° C., and the second color-changing activation temperature can be at least 5° C. greater than the color-changing activation temperature.

The present disclosure is drawn to an electronic device housing that can include a heat sensitive coating and a second heat sensitive coating applied to an electronic device housing. The heat sensitive coating or portion thereof can include a thermochromatic colorant having a color-changing activation temperature, and the second heat sensitive coating or portion thereof can include a second thermochromatic colorant having a second color-changing activation temperature. The color-changing activation temperature can be a temperature from 30° C. to about 100° C., and the second color-changing activation temperature can be at least 5° C. greater than the color-changing activation temperature.

Provided is a heating patch. The heating patch includes: a flexible plate-shaped base substrate; an electrode portion including a pair of lead electrodes formed on at least one surface of the base substrate along a longitudinal direction to be spaced apart along a width direction of the base substrate, and a pair of branch electrodes extending from the lead electrodes along the width direction of the base substrate to be not electrically connected to each other and to be overlapped with each other; a heating portion including a conductive heating material disposed in an overlapped part between the branch electrodes which have a predetermined area and face each other to generate heat while conducting the pair of branch electrodes to each other; and a pair of cover members disposed on both sides of the base substrate to prevent the electrode portion and the heating portion from being exposed externally.