Disclosed is a thermochromic microencapsulated pigment which comprises as four essential components (a) an electron-donating chromatic organic compound, (b) an electron-accepting compound, (c) a reaction medium determining the temperatures at which the color reactions of component (a) with component (b) take place, and (d) a color change temperature regulator, the color change temperature regulator (d) comprising one or more compounds selected from the group consisting of esters, alcohols, ketones, acid amides, hydrocarbons, and fatty acids and having a melting point Y (°C) satisfying the relationship (X+30)°C≤Y≤200°C, wherein X (°C) is the melting point of component (c), and the four essential components being microencapsulated.
A thermally color-developing reversibly thermochromic pigment which shows a uniform color density in the coloring temperature range and also shows an optional ΔH value within a range of from 3 to 40°C of the ΔH value (hysteresis temperature range) in a temperature-color density curve. Thermally color-developing reversibly thermochromic pigments of a three component system having a ΔH value of within a range of from 7 to 40°C in which at least essential three components including (a) an electron-donating chromic organic compound, (b) a specified compound selected from gallic acid esters and (c) a reaction medium selected from alcohols, esters, ketones and hydrocarbons, which reversibly generates color reactions of both of the compounds within a specified temperature range and has a melting point of less than 50°C, are microencapsulated, and of a four component system having a ΔH value of within a range of from 3 to 25°C in which a compound (d) selected from monomer compounds having a melting point of 50°C or more or polymer compounds having a softening point of 70°C or more is added to the three component system.
REVERSIBLY THERMOCHROMIC COMPOSITION, AND REVERSIBLY THERMOCHROMIC MICROCAPSULE PIGMENT HAVING SAME ENCLOSED THEREIN
申请人:The Pilot Ink Co., Ltd
公开号:EP3608386A1
公开(公告)日:2020-02-12
[Problems]
The present invention provides a highly marketable reversibly color changeable composition which provides a vivid yellow to orange color during color development, turns colorless during decoloration, and improves light resistance and a reversibly thermochromic microcapsule pigment encapsulating the same.
[Solution]
Disclosed are a reversibly thermochromic composition including: (a) a specific pyridine derivative as an electron-donating color-developing organic compound; (b) 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 same.
REVERSIBLE THERMOCHROMIC COMPOSITION, REVERSIBLE THERMOCHROMIC MICROCAPSULE PIGMENT COMPRISING SAME, AND WRITING INSTRUMENT USING SAME
申请人:THE PILOT INK CO., LTD.
公开号:EP3950068A1
公开(公告)日:2022-02-09
[Problems] Provided are a highly marketable reversibly thermochromic composition that provides a black color during color development by using a fluoran derivative having a specific structure as an electron-donating color-developing organic compound, turns colorless during decoloration, and is excellent in contrast between a colored state and a decolored state and a microcapsule pigment encapsulating the same.
[Solution] Disclosed are a reversibly thermochromic composition including: (a) a fluoran derivative having a specific structure as an electron-donating color-developing organic compound; (b) 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 same.
A microencapsulated pigment including a leuco dye system is incorporated as one or more layers in a roll of adhesive tape. The tape is applied and may be rubbed by hand or another object to induce a color change. The change may serve as an indicator that the tape is well adhered for masking purposes in a painting operation, or to present a design where only selected portions of the tape are rubbed to induce the color change. The microencapsulated pigment may be constructed so that the color change is irreversible or reversible.