I have recently presented T 476/09 (here). The decision also contains a discussion on the correct interpretation of claim 1 of the third auxiliary request, which read:
Claim 1 of the main request on file read:
1. A toner for developing a latent electrostatic image comprising:a base of toner particle which comprises a binder resin and a coloring agent; andan external additive,wherein a plurality of the base of toner particle has a volume average particle diameter (Dv) of 3 µm to 7 µm, a ratio (Dv/Dn) of the volume average particle diameter (Dv) to a number average particle diameter (Dn) is 1.01 to 1.25, a plurality of the base of toner particle comprises 15% by number or less of the base of toner particle having a particle diameter of 0.6 µm to 2.0 µm, a plurality of the base of toner particle has a circularity of 0.930 to 0.990 on average, the binder resin comprises a modified polyester resin, and the toner comprises 0.3 parts by weight to 5.0 parts by weight of the external additive, relative to 100 parts by weight of the base of toner particle,wherein the base of toner particle further comprises wax, the wax is dispersed in the base of toner particle, and more of the wax is present in a vicinity of a surface of the base of toner particle rather than a center of the base of toner particle. (my emphasis)
There was a discussion on the meaning of the term “vicinity”.
[10.1] It was a matter of dispute between the parties how the requirement in claim 1 that “more of the wax is present in a vicinity of a surface of the base of toner particle rather than a center of the base of toner particle” has to be interpreted.
[10.2] The [opponent] was of the opinion that the term “vicinity” could be interpreted such that toner particles with a uniform wax distribution would also meet this requirement. The [opponent] in particular argued that for any wax distribution, including a uniform one, the area covered by the “vicinity” could be chosen so large that the amount of wax present in this area was larger than the amount of wax outside of this area. Hence, in the respondent’s view, a toner particle with a uniform wax distribution met the requirement that more wax is present in the vicinity of the surface of the toner particle.
[10.3] The board cannot follow this claim interpretation. To interpret the requirement in claim 1 such that wax is present in any portion of the particle in the same amount (i.e. uniformly distributed) is in direct contradiction to the literal meaning of the claim and in fact deprives it of any technical sense. Moreover, it follows from the description of the opposed patent […] that a large amount of the wax has to be present in the toner near the surface and in particular that “the wax is dispersed to 1 µm or less in terms of the longer diameter”. This can only imply that the vicinity in claim 1 covers a region near, i.e. of up to 1 µm from the surface of the toner particles.
The file wrapper can be found here.