PURPOSE: A color-developing ink for pressure-sensitive copying paper that is composed of a color-developing agent of a mixture of reaction product between a specific condensate and a polyvalent metal compound, solvents and pigments, thus showing remarkably improved color-developing properties and light resistance and brightness of developed images thereof.
CONSTITUTION: The condensate resulting from the reaction of a mixture of p- hydroxybenzoic acid and a p-substituted alkylphenol bearing a 1W12C alkyl group at a molar ratio of (0.1W5):1 with formaldehyde in the presence of an acidic catalyst such as phosphoric acid is allowed to react with a polyvalent metal compound such as an oxide of metal such as zinc at a weight ratio of (95:5)W(20:80), preferably at 80W180°C to prepare an electron-accepting color developer. Then, the resultant color developer is mixed with solvents such as linseed oil and pigments such as titanium oxide to form an ink, thus giving the objective color-developing ink for pressure-sensitive copying paper.
USE: For letter-press and off-set printing.
MORISHITA SADAO
HIRAISHI SHIGETOSHI
KURAMOTO ATSUO
YOSHIOKA HIROSHI
MITSUBISHI GAS CHEMICAL CO
| JPS5359159A | 1978-05-27 | |||
| JPS4814409A |