Abstract: Light oil for reduced particulate emission which minimizes both the SOF and ISF of particulate matter emitted from a diesel engine is provided. The light oil for reduced particulate, (especially reduced SOF) emission comprises hydrocarbons, with the content of the distillation residue at 320° C. being 3% by volume or less in a distillation test according to ASTMD86-90. The light oil for reduced particulate (especially reduced soot) emission comprises straight chain paraffin, wherein when hydrocarbons except straight chain paraffin are mainly composed of branched chain paraffin and/or naphthene, their contents are 2% by volume or less, and when hydrocarbons except straight chain paraffin in the fuel are mainly composed of aromatics, their contents are 1% by volume or less.

Abstract: A fuel injection apparatus in which the state of vaporization of the fuel in the internal combustion engine is improved by making the fuel spray injected from the fuel injector not strike the umbrella portion of the intake valve from the front, but be oriented to a position shifted to the right or left of the stem so that the majority of the spray flows in to a valve seat clearance of an annular groove shape formed between the valve face and the valve seat and causes a swirl in the same. The wet amount of the fuel depositing as a liquid film on the umbrella portion and the inner surface of the intake port, which is difficult to evaporate, is reduced.