| 摘要 |
The invention relates to a method for producing pressure-sensitive adhesives that have low or no anisotropy, the process elements including an adhesive supply system, an application unit and a placement element. A melt strip of the pressure-sensitive adhesive is produced between the outlet of the application unit and the point of placement on the placement element and is stretched. The invention is characterized by controlling the stretching of the pressure-sensitive adhesive in the free melt strip by adjusting an effective ratio G which is defined as the ratio of the effective timeΔt of the stretching to the stretching rate R, and which is adjusted to a value of at least 0.006 s2 or to a value of not more that 0.004 s2. The effective timeΔt is defined by the formula 2Lr/[vstrip(1+r)] wherein L is the length of the melt strip, r is the stretching ratio and vstrip is the speed of the melt strip and the stretching rate R is defined as a temporal derivative of the stretching ratio r. |
