1. A method for measuring low levels of a substance in a sample, said method comprising the steps of:
dispersing a plurality of paramagnetic particles in a colloidal solution;
introducing an amount of said colloidal solution into a sample chamber;
subjecting said sample chamber to a substantially uniform magnetic field;
forming at least one substantially linear structure from said plurality of paramagnetic particles with said substantially uniform magnetic field;
introducing a sample having low levels of said substance to be measured into said sample chamber for analysis;
rotating said substantially uniform magnetic field at a constant rate to cause said substantially linear structure to rotate therewith;
binding a portion of said substance to be measured in said sample to said substantially linear structure;
detecting signals having a time-varying component originating from said sample chamber; and
processing said signals with a lock-in amplifier to measure said time-varying component by improving the signal-to-noise ratio thereof using a reference signal having a frequency twice that of the rotation of said substantially uniform magnetic field as a multiplier to measure said low levels of said substance to be measured.
2. A method as claimed in claim 1 wherein said paramagnetic particles are coated with amine groups, and wherein said substance to be measured in said sample binds with said amine groups.
3. A method as claimed in claim 1 further comprising the step of exposing said sample chamber to an excitation source.
4. A method as claimed in claim 3 wherein said excitation source is a light source.
5. A method as claimed in claim 4 wherein said light source is a laser.
6. A method as claimed in claim 4 wherein said light source is a light-emitting diode (LED).
7. A method as claimed in claim 4 wherein said signals having a time-varying component are detected with a photomultiplier (PM) tube.
8. A method as claimed in claim 4 wherein said signals having a time-varying component are detected with a charge-coupling device (CCD).
9. A method as claimed in claim 1 wherein said substantially uniform magnetic field is generated by a permanent magnet.
10. A method as claimed in claim 9 wherein said substantially uniform magnetic field is rotated by rotating said permanent magnet.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An electrophotographic toner comprising a resin and a colorant, wherein the colorant comprises a pigment of C.I. Pigment Blue 76.
2. The toner of claim 1, wherein the pigment of C.I. Pigment Blue 76 is contained in an amount of from 1 to 10% by mass of the toner.
3. The toner of claim 1, wherein the pigment of C.I. Pigment Blue 76 is contained in the form of particles having a number average primary particle size of from 10 to 300 nm.
4. The toner of claim 1, wherein the colorant further comprises a cyan pigment in an amount of less than 50% by mass of the pigment of C.I. Pigment Blue 76.
5. The toner of claim 1, wherein the colorant is contained in an amount of from 1 to 10% by mass of the toner.
6. The toner of claim 1, wherein the toner comprises toner particles having a volume-based median diameter of from 3 to 8 \u03bcm.
7. The toner of claim 1, wherein the toner comprises toner particles having a coefficient of variation of volume-based particle size distribution of from 2 to 21%.
8. The toner of claim 1, wherein the toner exhibits a softening point of from 70 to 110\xb0 C.
9. The toner of claim 1, wherein the resin comprises a polymer formed of at least a monomer having at least one selected from the group of a carboxyl group, a sulfonic acid group and a phosphoric acid group.
10. An electrophotographic toner comprising a resin and a colorant, wherein the colorant comprises a pigment represented by the formula:
wherein n is 10.
11. A full-color toner kit comprising a yellow toner comprising a yellow colorant and a binder, a magenta toner comprising a magenta colorant and a binder, a cyan toner comprising a cyan colorant and a binder and a black toner comprising a black colorant and a binder, wherein the cyan colorant comprises a pigment of C.I. Pigment Blue 76.
12. An image forming method comprising performing image formation by using at least four toners comprised of a yellow toner comprising a yellow colorant and a resins a magenta toner comprising a magenta colorant and a resin, a cyan toner comprising a cyan colorant and a resin and a black toner comprising a black colorant and a resin, wherein the cyan colorant comprises a pigment of C.I. Pigment Blue 76.