FIELD: manufacturing technology.
SUBSTANCE: invention relates to a cardboard cylindrical tube that has a wounded web of absorbent material. Rupturable core adapted for winding the sheet product comprises a wall of a cylindrical body defining a longitudinal hole along the longitudinal axis XX'. Wall of the cylindrical body is torn apart from the edge. Wall of the cylindrical body contains an outer tape and an inner tape. Outer tape is one part of the turn apart wall of the cylindrical body adapted to be in contact with the wound sheet product, and the inner band is another part of the turn apart wall of the cylindrical body facing the longitudinal opening. Outer tape and the inner tape are spirally wound on each other and offset with overlap in the transverse direction parallel to the longitudinal axis XX'. Outer tape and the inner tape are bonded together through their mutually facing surfaces through the first attachment region. Tapes are made of materials having such characteristics that either the inner tape is made of cardboard having a smaller water transmission, than the transmission of water from the outer tape, or the outer tape is made of cardboard having a water transmission that is less than the transmission of water of the inner tape. Wall of the cylindrical body is formed as a core tube by bonding at the place of the outer tape. First end portion of the outer tape of one winding is superimposed and fixed to the second end portion of the outer band of the adjacent turn through their mutually facing surfaces through the second attachment region. Sheet product roll contains a sheet item wound around the turn apart core. Produce an outer tape and an inner tape. Outer tape and the inner tape are assembled by a biased overlap of the outer tape and the inner tape in a transverse direction parallel to the longitudinal axis XX'. Outer tape and the inner tape are coupled through their mutually facing surfaces through the first attachment region. Assembled outer and inner straps are helically wound spirally in a way that the wall of the cylindrical body is formed as a core tube by coupling in place of the outer tape. Cut the turn apart core to a certain length.
EFFECT: facilitates the production of a turn apart core.
17 cl, 7 dwg
