•  On Nov, 16, 2012
•  DST
•   Surface Cleaning

Various PVA Sponge Roller

PVA sponge roller is used in many wet surface cleaning process.  Hard disc substrate and wafer cleaning process are the 2 cleaning processes that require high quality PVA sponge roller products.  Perhaps PVA sponge roller design could play a very important role for achieving better cleaning result.

Once a wet surface cleaning process has been setup, it is not very convenient for changing a new process layout as this involve resource, cleaning machine, line re-location and space.  Under such circumstances, PVA sponge roller comes into role that by changing the design of PVA sponge roller and optimizing the process parameters, cleaning field engineer could experience difference cleaning result.

Let us review several common varieties of PVA sponge roller we could select in order to obtain optimize cleaning result for wet surface cleaning process.

Shape of PVA Sponge Roller or Brush

Circular/Disc shape PVA surface brush.

Circular Surface Brush

This is the common design for circular scrubbing motion.  Since the appearance did not look like roller, some time it also name as “Brush” instead of roller.

Roller shape PVA sponge roller.

This is the common design use in PCB industry.  Due to it “smooth” surface structure, this type of circular sponge roller mainly use for hydration purpose instead of cleaning.

Outer Design of PVA Sponge Roller

Nodular PVA sponge roller.

Nodular sponge roller is commonly use in many post-wafer cleaning process and disc-drive substrate cleaning.  For instance Ontrak DSS200 is using nodular sponge roller. The nodular roller is trade-off the scrubbing force by enhancing cleaning solution flow.  Particle attached on the substrate surface will be scrubbed by the nodular and immediately flush away by the cleaning water.  This makes the sponge roller become suitable for most of the surface contaminant which not tightly attached on the surface.

Spline PVA sponge roller.

This is the PVA sponge roller introducing maximum scrubbing mechanical force, however under this design, the cleaning detergent flow has been reduced due to the spline structure on the roller.

If the contaminant is more stubborn and securely attach on the substrate surface, spline roller may be more suitable.  However for loose contaminant, the spline roller may not effectively remove.

Other surface design.

We have other outer design of PVA sponge roller, unfortunately those design are proprietary for individual customer.

Micro Structure of PVA Sponge Roller

Sponge roller pore size.

PVA roller pore size is one of the common over-look factors for many field-cleaning engineers.  From our pass working experience, by selecting the proper pore size for individual cleaning process, we may get significant improvement in cleaning result.

Sponge roller pore structure.

Getting a consistent pore structure throughout the PVA sponge roller is a challenging process. During foaming process, all parameters need to precisely control in order to get a consistent pore structure.  The inconsistent of pore size may cause flow disturbance for cleaning detergent.  This may cause contaminant being trapped in the roller without flushing out.  The trapped contaminant may also scratch the substrate surface.

DST Technology has been deeply involved in PVA sponge roller selection.  Through our understanding of PVA sponge roller and experience in cleaning process, we are confident be able to help cleaning engineer for optimizing their wet surface cleaning process via proper selection of PVA sponge roller.