- How do I extend the stability of my pre-catalyzed wood glue?
- What is the role of "Humectant" used in the water-based adhesives?
- How do I produce an "acid-free" adhesive?
- What are the general requirements that MUST be fulfilled for a window patching adhesive?
- How do I calculate the glue consumption in Finger Jointing?
Q. How do I extend the stability of my pre-catalyzed wood glue?
There are many methods to make minor improvements in the pre-catalyzed wood glue's stability. However, the most significant improvements should start with the base emulsion.
GB's new cross-linkable polyvinyl acetate emulsion, GB Latex 0048CR base emulsion and ready-to-use GB Bond 699 adhesive deliver an outstanding pre-catalyzed storage stability. These products alone can fulfil European EN 204 C D3 bond requirements while offering a shelf life in excess of six months.
Q. What is the role of "Humectant" used in the water based adhesives?
A Humectant is a hydroscopic substance that absorbs and retains moisture from the atmosphere. In water-based adhesives, the Humectant prevents the surface of the adhesives to form a skin by keeping it wet.
By retarding drying, the Humectant also slows the adhesive's setting speed and extends its open time. In addition, the Humectant allows easier clean up of built-up adhesives.
Q. How do I produce an "acid-free" adhesive?
Acid-free is referring to a term describing materials with a pH value of 7.0 or higher. Adhesive products, which mainly use a Polyvinyl Acetate homo-polymer or Ethylene vinyl acetate co-polymer base, commonly are mild acetic with a pH value of 4.0 - 5.0.
A buffering agent, such as sodium acetate or a small amount of sodium bicarbonate, is added to the formulation to reach the neutral pH. The principle here is the same as when a person has gastric and he takes an antacid, which neutralizes the acid and makes him feel better.
Q. What are the general requirements that MUST be fulfilled for a window patching adhesive?
Window patching adhesives must fulfil the following requirements:
- Ensure good bonding of paper to different types of film (glassine/synthetic)
- The adhesive must not cause discolouriation of the envelope
- The adhesive must not splash, and have good roller stability and low foam foaming
- The adhesive must have the right wet tack strength to immediately adhere to the window film on the paper
- The adhesive must have a high-solid content with anti-wrapped properties
Q. How do I calculate the glue consumption in Finger Jointing?
|W||=||Width of lamellas in meter||48mm|
|Lf||=||Average Length of lamellas to be jointed||300mm|
|N||=||Number of fingers in lamellas||20|
|Lw||=||Length of finger||8mm|
Glue Consumption per m3 when Finger Jointing:
2 x 0.008m x 0.2kg/m2 x 20
0.048m x 0.3m