Binder resin for toner and toner
AssigneeMitsui Chemicals, Inc.
InventorsTomoya Terauchi, Hirotaka Uosaki, Hiroshi Matsuoka, Yuji Emura, Hiroyuki Takei, Hironobu Hashimoto
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Abstract
A binder resin for a toner comprises a polyester component having a specific structure which is not soluble in tetrahydrofuran, and a polyester component having a specific branched structure which is soluble in tetrahydrofuran. The binder resin can provide a toner, which is superior in low-temperature fixation and offset resistance and can be used in high speed printing in response to the recent market demands owing to its specific structure.
Claims10
A binder resin for a toner comprising a polyester resin, wherein
- the polyester resin comprises 0.1 to 40% by weight of tetrahydrofuran insoluble component (A-1) and 99.9 to 60% by weight of tetrahydrofuran soluble component (A-2);
- the tetrahydrofuran insoluble component (A-1) has a polyester structure unit comprising;
- a terephthalic acid-derived structure unit (I),
- a polyhydric alcohol-derived structure unit (II) comprising 39.9 to 75 mole % of a dihydric alcohol-derived structure unit (II-1-1) having 2 to 10 carbon atoms,
- 0.1 to 20 mole % of a trihydric alcohol-derived structure unit (II-1-2) having 3 to 10 carbon atoms and
- 15 to 60 mole % of a dihydric alcohol-derived structure unit containing bisphenol skeleton (II-2),
- each mole % being based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in component (A-1), and
- 0.1 to 30 mole % of di- or higher functional atomic group structure unit (III) of 1 to 20 carbon atoms having one or more kinds of elements selected from C, H, N, O and S, based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in component (A-1);
- and
- the tetrahydrofuran soluble component (A-2) has a polyester structure unit comprising;
- a terephthalic acid-derived structure unit (I),
- a polyhydric alcohol-derived structure unit (IV) comprising
- 40 to 85 mole % of a dihydric alcohol-derived structure unit (IV-1) having 2 to 10 carbon atoms and
- 15 to 60 mole % of a dihydric alcohol-derived structure unit containing bisphenol skeleton (IV-2),
- each mole % being based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in component (A-2),
- 2 to 20 mole % of tri- or higher functional atomic group structure unit (V) of 1 to 20 carbon atoms having one or more kinds of elements selected from C, H and O, based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in component (A-2), and
- 0 to 10 mole % of di- or higher functional atomic group structure unit (VI) having 1 to 20 carbon atoms based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in component (A-2).
A binder resin for a toner comprising a polyester resin (A) obtained by reacting a polyester resin (a-1) with a polyester resin (a-2) and di- or higher functional isocyanate (iii), wherein the polyester resin (a-1) comprises;
- a terephthalic acid-derived structure unit (I),
- a polyhydric alcohol-derived structure unit (II) comprising
- 39.9 to 75 mole % of a dihydric alcohol-derived structure unit (II-1-1) having 2 to 10 carbon atoms,
- 0.1 to 20 mole % of a trihydric alcohol-derived structure unit (II-1-2) having 3 to 10 carbon atoms and
- 15 to 60 mole % of a dihydric alcohol-derived structure unit containing bisphenol skeleton (II-2),
- each mole % being based on 100 mole % of the total moles of all the polyhydnc alcohol-derived structure unit in polyester resin (a-1);
- the polyester resin (a-2) comprises;
- a terephthalic acid-derived structure unit (I),
- a polyhydric alcohol-derived structure unit (IV) comprising
- 40 to 85 mole % of a dihydric alcohol-derived structure unit (IV-1) having 2 to 10 carbon atoms and
- 15 to 60 mole % of a dihydric alcohol-derived structure unit containing bisphenol skeleton (IV-2),
- each mole % being based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure unit in polyester resin (a-2), and
- 2 to 20 mole % of tri- or higher functional atomic group structure unit (V) of 1 to 20 carbon atoms having one or more kinds of elements selected from C, H and O, based on 100 mole % of the total moles of all the polyhydnc alcohol-derived structure unit in polyester resin (a-2).
A process for producing a binder resin for a toner comprising the steps of:
- producing a polyester resin (a-1) depolymerization and polycondensation of
- a terephthalic acid derivative (i),
- a polyhydric alcohol (ii) comprising
- a dihydric alcohol (ii-1-1) having 2 to 10 carbon atoms,
- a trihydric alcohol (ii-1-2) having 3 to 10 carbon atoms and
- a bisphenol or a derivative thereof (ii-2), and
- a terephthalic acid polyester resin (vii);
- producing a polyester resin (a-2) of depolymerization and polycondensation
- the terephthalic acid derivative (i),
- a polyhydric alcohol (iv) comprising
- a dihydric alcohol (iv-1) having 2 to 10 carbon atoms,
- a bisphenol type derivative (iv-2) and
- a tri- or higher alcohol (iv-3) having 1 to 20 carbon atoms, and
- the terephthalic acid polyester resin (vii);
- and
- reacting the polyester resin (a-1), the polyester resin (a-2) and a di- or higher functional isocyanate (iii).
A binder resin for a toner wherein the binder resin is obtained by reacting a polyester resin (a-1) with a bi- or higher functional isocyanate (iii) in the presence of a low-molecular weight wax (vii).
Dependencies are inferred from the claim text.