Case Study
Amslip SCR™
Anti-Scratch Additives
Amcor offers a selection of anti-scratch additives under the name Amslip SCR™.
The specific grade of Amslip SCR™ depends on type of resin, process, application, color, etc. Amslip SCR™ will have no negative influence on surface migration additives like UV inhibitors, etc.
Although you cannot “judge a book by its cover”, when it comes to plastics, appearance is often the key characteristic of perceived quality. Many plastics are susceptible to scratches which create an impression of lower quality. The addition of Amslip SCR™ (anti- scratch additive) will reduce the width of the scratch, minimize scratch whiteness and improve the smoothness; thereby greatly reducing the visibility of the scratch and maintain the perceived quality.
Scratch Width
In order to mimic scratches and quantify them, a test similar to the five finger test that is often required for the automotive industry was performed. The test made it possible to quantify a scratch based on the width and onset. When the scratch load causes noticeable damage, the scratch consists of area damaged by the scratch tip and material mounded up on the edges. Test results appear in the graph and show that the onset of scratches occurs at a load force of 2N and that when Amslip SCR™ is added at 1% the onset does not occur until a force of 6N. Furthermore, at force loadings greater than 6N the width of the scratch was greatly reduced.
Scratch Whitness
L on the L*a*b* color scale is a measurement of lightness. Where 100 equals white and 0 equals black. By measuring the L value of the scratch and subtracting the L value of the background you are able to determine the dL (delta L), the difference in whiteness of scratches compared to background. Low dL values indicate little to no difference in the lightness between the scratch and background so the scratch has low visibility. The graph shows results for Black PP and Black PP with 1% Amslip SCR™. The Black PP samples had a measurable difference of 20 dL at the lowest loads and 60 dL at the highest load. While the Black PP with 1% Amslip SCR™ showed no measurable difference in low to medium loads and only a dL of 10 at the highest loads.