| 摘要 |
<p>PURPOSE: To attain rapid kick-off of electrostatic charge even in the case of a toner not contg. an electrostatic charge regulating agent or contg. a reduced amt. of the agent and to ensure a sufficiently large quantity of electric charges by using specified two kinds of ethylene polymers as constituent components. CONSTITUTION: An ethylene polymer (L) having a wt. average mol.wt. (Mw) of <=20,000, preferably <=10,000 and 2-100mgKOH/g, preferably 5-30mgKOH/g acid value and an ethylene polymer (H) having a wt. average mol.wt. (Mw) of >=150,000, preferably >=300,000 are used as constituent components. In the build-up of electrostatic charge of the polymer H, time constant (τ) obtd. from the equation Q=(Qmax)×[1-exp(-t/τ)] is 1.2-25, preferably 1.2-18 and the ratio of the Mw of the polymer H to the number average mol.wt. (Mn) is >=-5.0. In the equation, (t) is triboelectric charge treatment time (min)τis time constant (min) of build-up of electrostatic charge, Q is the quantity (μC/g) of electric charges in triboelectric charge treatment time (t) and Qmax is the max. quantity (μC/g) of electric charges.</p> |
