Pond
pond
style size press is an older designed surface size coaters. Prior to Sym Sizers Starch was applied directly between two rolls creating a "pond" of starch.
Paper passes through the liquid phase and is pressed between the size press rolls. prior to the Size press the Paper is dried to a Moisture content between 8 to 12 %. this is the ideal moisture range to accept liquid back into the paper.
The moment the paper comes into contact with the Starch it starts to be absorbed into the paper. the advantage to pond size presses is that more starch can be applied to the paper sheet than sym sizers. this is due to the increased contact time with the starch. the pond level, or amount of starch within the two rolls typically can be adjusted to control the amount of starch absorbed into the sheet.
Paper passes through the liquid phase and is pressed between the size press rolls. prior to the Size press the Paper is dried to a Moisture content between 8 to 12 %. this is the ideal moisture range to accept liquid back into the paper.
The moment the paper comes into contact with the Starch it starts to be absorbed into the paper. the advantage to pond size presses is that more starch can be applied to the paper sheet than sym sizers. this is due to the increased contact time with the starch. the pond level, or amount of starch within the two rolls typically can be adjusted to control the amount of starch absorbed into the sheet.
With greater starch pick up from the pond the sheet will also contain more water after application. Leaving the Pond the sheet can contain almost as much as 40% Moisture.
The higher moisture content leaving the size press does have its disadvantages. the high moisture content will weaken the sheet. this section of the paper machine can be responsible;le for majority of the paper breaks incurred.
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