A safety razor blade unit has two or more blades ( 19,20,21 ) with parallel cutting edges ( 24,25,26 ) mounted in a frame ( 10 ) between guard and cap surfaces so that the average inter-blade span is not greater than 1.25 mm, and the wash through index, a measure of the rinsability obtained by a method defined in the specification, is not less than 0.20. The combination of narrow inter-blade spans and good rinsability enables enhanced comfort levels during shaving to be achieved.
1. A safety razor blade unit comprising:
a frame, said frame comprising frame ends, each one of the frame ends comprising multiple slots and a stop shoulder,
at least four blades supported by the frame, the blades having respective forwardly directed cutting edges extending along the blade unit, each one of the blades being positioned within a respective one of the multiple slots in each one of the frame ends,
a guard structure on the frame providing a surface for contact with skin during shaving forward of the blades,
a cap structure on the frame providing a surface for contact with the skin during shaving rearward of the blades,
the blades are vertically movable from rest positions within the slots under forces imparted on the blades during shaving and the blades are movable independently of each other against actions of respective return springs, and in the rest positions the blades are arranged so that the cutting edge of each of said blades contacts said stop shoulder to lie substantially in a common plane extending between the contact surfaces of the guard structure and cap structure.
2. The safety razor blade unit according to claim 1 , wherein said blades include an inter-blade span between adjacent ones of said blades.
3. The safety razor blade unit according to claim 2 , wherein the inter-blade span of the blades are uniform.
4. The safety razor blade unit according to claim 1 , wherein each of said blades comprise a substantially planar strip carried on a respective blade support.
5. The safety razor blade unit according to claim 4 , wherein each of said blade supports is narrower than the planar strip it carries.
6. The safety razor blade unit according to claim 4 , wherein each of said blade supports comprises a bar with parallel front and rear faces and a forwardly and upwardly inclined top face.
7. The safety razor blade unit according to claim 1 , wherein the guard structure includes a strip of elastomeric material.