| abstract |
PROBLEM TO BE SOLVED: To have a selective wavelength absorption function in a wavelength range from visible light to near infrared light, to have a sharp light absorption characteristic, to have a small influence on surrounding wavelengths, and to obtain a highly saturated color tone. Provide gold fine particles. SOLUTION: An aspect ratio is 1.1 to 8.0, a selective wavelength absorption function is provided in a wavelength range of 400 nm to 1200 nm, and an extinction coefficient at a peak position of a maximum absorption wavelength is 6000 to 20000 L / mol. Contains gold fine particles characterized by having a high absorbance of cm (measured concentration 1.6 × 10-4 mol / L, solvent: water) and having a half-value width of the absorption spectrum of the maximum absorption wavelength of 200 nm or less Composition. [Selection] Figure 1 |