Fuji Xerox Co., Ltd.

Rank Xerox Ltd.

Yasuji Fukase

Koichi Tanaka

Yasuhiro Uehara

Hiroshi Takayama

Yoshio Shoji

Shigeo Aonuma

Hiroo Nishide

Yoshimi Amagai

Disclosed is a fixing device where a copying medium carrying a non-fixed toner image thereon is passed between a pair of fixing rolls as being kept in direct contact with each other under pressure so as to fix the non-fixed toner image on the copying medium, the device being characterized in that a toner release at least containing, as an active ingredient, a functional group-containing organopolysiloxane of a general formula (I): ##STR1## the organopolysiloxane having a viscosity of from 10 to 100,000 cs at 25.degree. C., is supplied to at least the fixing roll of being brought into contact with the non-fixed toner image of the said pair of fixing rolls. Using the toner release, the copying medium releasability from the fixing roll to which the toner release is applied is good and the heat-resistance of the fixing roll is also good.

Fixing device

A toner for developing an electrostatic latent image characterized by a vinyl copolymer whose acid value is in the range of about 5 to 100.

Toner for developing electrostatic latent image containing copolymer of

A contact heat fixing apparatus comprising heat roll 1 having metal core 3 coated with heat resistant toner releasing material 4 on the surface thereof and provided with a heating element to the inside thereof. Temperature control circuit A comprising detection circuit 15 for the detection of the surface temperature of heat roll 1, comparison circuit 16 for comparing the level of a signal issued from said detection circuit 15 with that of a reference signal, pulse generation circuit 17 for converting the signal produced from said comparison circuit 16 into a pulse and an alternating current power source 12 whose electric power to be supplied to said heating element 11 is controlled by the signal from said pulse generation circuit, and switching circuit B for applying, to said temperature control circuit A, control signals which control the surface temperature of said heat roll 1 to set temperature T.sub.1 during a copy stand-by period, to set temperature T.sub.2 lower than said set temperature T.sub.1 during copy operation after a certain period from the start of copy, and again to set temperature T.sub.1 after another certain period from the completion of copy operation.

Contact heat fixing apparatus

A fixing apparatus with heat and pressure for electrophotographic copiers, the apparatus comprising a first roll 1, with which a toner image 11 on a paper 10 to be fixed comes into contact, and a second roll 2 placed in pressure contact with said first roll for rotation, said paper 10 passing between both the rolls 1 and 2, characterized in that a heat generating source 3b is provided at least in the second roll 2, a resilient material 5 having a heat-resistant releasing property is coated on the surface of the first roll 1, the surface of the second roll 2 being formed into a metal surface, and a releasing agent 7 containing a functional group is supplied to at least the surface of the second roll 2.

Growing community of inventors

Ebina, Japan

Yasuji Fukase