Abstract: First and second engaging projected portions are formed on opposing circumferential surfaces of a tubular casing and a hollow lead portion which are rotated relative to each other so as to be coupled with, thereby spirally engaging external and internal threads formed on the respective opposing circumferential surfaces. A forward side face of the first engaging projected portion with respect to a spiral rotating direction is formed into a slanting face so as to allow the second engaging projected portion to move over the first engaging projected portion when the casing and the lead portion are completely coupled with each other. Further, backward side faces of the first and second engaging projected portions are formed into upright faces, such that the second engaging projected portion cannot move over the first engaging projected portion in an opposite direction once moving over the same. This arrangement reliably prevents the spiral engagement of the casing and the lead portion from loosening.

Abstract: First, second, and third bottom stepped portions 18, 20, 22 are formed stepwise at a lead end portion of a casing 10 of a liquid applicator. First, second, third, and fourth lead stepped portions 32, 34, 36, 38 are formed stepwise at a bottom end portion of a lead portion 12 of the liquid applicator. Lead end faces 24, 26 of the second and third bottom stepped portions 20, 22 are adhered with bottom end faces 40, 42 of the second and third lead stepped portions 34, 36 by means of an ultrasonic adhesion in a state where the respective bottom stepped portions are brought into contact with the corresponding lead stepped portions. Accordingly, the adhered faces are prevented from coming apart at each adhered portion in the liquid applicator including lead and bottom side shafts which are coupled with each other by means of ultrasonic adhesion.

Abstract: A liquid applicator includes a tubular casing, a liquid holding member, and a support member. The support member whose modulus of elasticity is smaller than that of the liquid holding member is provided between a bottom end portion of the liquid holding member and a bottom wall of the casing. The support is formed such that at least a portion of an outer circumferential surface of the support member is in pressing contact with an inner circumferential surface of the casing and that the support member is compressively deformable in an axial direction thereof while being held tightly between the liquid holding member and the bottom wall of the casing. Accordingly, the liquid holding member can be reliably supported in the casing.