Abstract: A temperature indicator includes a compound comprising an ionic fluid disposed in contact with an absorbent medium at a first location. Detection circuitry is coupled to the absorbent medium at a second location spaced apart from the first location. Communications circuitry is coupled to the detection circuitry and is configured to output a value indicating an actuation state of the temperature indicator indicated by the detection circuitry. Responsive to the temperature indicator being exposed to a temperature exceeding a temperature threshold, the compound migrates along the absorbent medium from the first location toward the second location. The detection circuitry is configured to indicate the actuation state based on a presence of the compound at the second location.

Abstract: Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (VI); R1, and R2 are independently selected from an optionally substituted linear or branched alkyl group, alkenyl group, alkoxy group, aryl group and an alkylene aryl group having from 5 to 22 carbon atoms; X1 and X2 are independently selected from —OC(O)—, —CO2— and O; Y1, and Y2 are independently selected from hydrogen, halogen, R1, —OR1; y is independently 0 or 1; and suitably the groups R1X1— and —X2R2 are independently in the ortho or meta position. 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.

Abstract: Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (I): wherein R1, and R2 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; X1 and X2 are selected from —OC(O)-, —CO2- and O; R3, R4 and R5 are selected from hydrogen and an linear or branched alkyl group, cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group; R6 is selected from hydrogen, R3, —X1R1 and aryl and halogen; Y1 Y2 Y3 and Y4 are selected from hydrogen, R3, —OR3 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 R6 is —CO2R1; and wherein when a is 0 and b is 1 and R5 or R6 is phenyl, R6 and R5 respectively are not hydrogen or C1-7 alkyl.

Abstract: The invention provides a colour change composition containing an electron donating organic colouring compound, an electron accepting compound and a compound of formula (I): wherein E is an ester linkage O—CO or —CO2, R is independently selected from an optionally substituted linear or branched alkyl group, alkenyl cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group having from 6 to 22 carbon atoms; Y1 Y2 X1 and X2 are independently selected from hydrogen, R?, —OR? and halogen; wherein R? is independently selected from an optionally substituted linear or branched alkyl group, alkenyl group, alkoxy group, aryl group and an alkylene aryl group; having from 5 to 22 carbon atoms; r and p each represent and integer from 0 to 3. The compound of formula (I) and compositions of the invention are useful in providing a colour change effect, in memory compositions and visual indicators, particularly in security and healthcare applications.

Abstract: Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (I): wherein R1, and R2 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; X1 and X2 are selected from —OC(O)—, —CO2— and O; R3, R4 and R5 are selected from hydrogen and an linear or branched alkyl group, cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group; R6 is selected from hydrogen, R3, —X1R1 and aryl and halogen; Y1 Y2 Y3 and Y4 are selected from hydrogen, R3, —OR3 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 R6 is —CO2R1; and wherein when a is 0 and b is 1 and R5 or R6 is phenyl, R6 and R5 respectively are not hydrogen or C1-7alkyl.

Abstract: A temperature-indicator product comprising a visual indicator comprising a thermochromic colour-memory composition and comprising an electron-donating colouring organic compound (A), an electron-accepting colouring organic compound (B) and reaction medium compound (C). The visual indicator comprises a first portion comprising a first thermochromic colour-change composition in its lower temperature state and a second portion comprising a second thermochromic colour-change composition in its higher temperature state. The product is useful as a tamper-evident indicator or as a freeze indicator.

Abstract: A temperature-indicator product comprising a visual indicator comprising a thermochromic colour-memory composition and comprising an electron-donating colouring organic compound (A), an electron-accepting colouring organic compound (B) and reaction medium compound (C). The visual indicator comprises a first portion comprising a first thermochromic colour-change composition in its lower temperature state and a second portion comprising a second thermochromic colour-change composition in its higher temperature state. The product is useful as a tamper-evident indicator or as a freeze indicator.

Abstract: A temperature-indicator product comprising a visual indicator comprising a thermochromic colour-memory composition and comprising an electron-donating colouring organic compound (A), an electron-accepting colouring organic compound (B) and reaction medium compound (C). The visual indicator comprises a first portion comprising a first thermochromic colour-change composition in its lower temperature state and a second portion comprising a second thermochromic colour-change composition in its higher temperature state. The product is useful as a tamper-evident indicator or as a freeze indicator.

Abstract: Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (VI); R1, and R2 are independently selected from an optionally substituted linear or branched alkyl group, alkenyl group, alkoxy group, aryl group and an alkylene aryl group having from 5 to 22 carbon atoms; X1 and X2 are independently selected from —OC(O)—, —CO2— and O; Y1, and Y2 are independently selected from hydrogen, halogen, R1, —OR1; y is independently 0 or 1; and suitably the groups R1X1— and —X2R2 are independently in the ortho or meta position. 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.

Abstract: Novel reaction media for electron donating and electron accepting components in colour-change compositions are described. The compound is of formula (I): wherein R1, and R2 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; X1 and X2 are selected from —OC(O)—, —CO2— and O; R3, R4 and R5 are selected from hydrogen and an linear or branched alkyl group, cycloalkyl group, alkenyl group, alkoxy group, aryl and alkylene aryl group; R6 is selected from hydrogen, R3, —X1R1 and aryl and halogen; Y1 Y2 Y3 and Y4 are selected from hydrogen, R3, —OR3 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 R6 is —C02R1; and wherein when a is 0 and b is 1 and R5 or R6 is phenyl, R6 and R5 respectively are not hydrogen or C1-7alkyl.