A. Surface Preparation
Surface preparation is the most important part of the coating procedure. It is extremely important to follow the steps for surface preparation carefully and remove all contamination so a strong bond between the substrate and the Liquid Window Insulation can be formed. This is the key part of the coating process and will greatly affect the final appearance of the product. At this point in the process it is recommended to follow all safety procedures, especially the use of Personal Protective Equipment (PPE).
1. Cleaning and Masking
Wipe down glass and window frame(s) with water or a common household- cleaning product using a paper towel to remove obvious contaminants. For difficult to remove stains, a razor blade scraper can be used. Avoid scratching or cracking the glass. Scrapers should never be used on plastic substrates. Glass Cleaner (Material S) can be used to degrease a surface and remove heavy soiling. Tape and Drape (Material Q) or disposable drop cloths should be utilized to cover flooring, walls, furniture, and other items from cleaning and coating materials. Apply the masking tape (Material I) to the window edges, seals and any other mechanisms that should be protected from being coated.
Wet a lint free paper towel such as Kimtech KimWipes or a micro-fiber cloth using the Glass Primer (Material C). Wipe the primer on the surface using a buffing motion and a good amount of force to remove all remaining contamination. The primer should leave a super-hydrophilic surface for coating. For larger areas, the following procedure should be used to apply the primer
- Ideal squeegee width ~ around 35cm
- Fold the microfiber cloth multiple times around the squeegee head, usually about 4 folds, until the cloth fits snug around the squeegee tip.
- The masking plastic can be placed over the tray.
- Pour primer into the plastic in the tray.
- The cloth will absorb about 10ml to wet the cloth -The coverage rate is about 10ml/m2
- Pour for about 1m2 (10ml) at a time
- During application, the squeegee head should be kept horizontal and should move down vertically with one motion from top to bottom.
- Primer should be applied at a slow, steady rate.
- Applying too quickly may leave uncoated areas resulting in a non-uniform finish.
- Let the first pass dry 2 minutes
- Repeat the same process for a second coat of primer
B. Coating Solution Preparation
Liquid Window Insulation is a two-part solution. It is important to note, that after mixing, the coating solution has a pot life of approximately 2 hours. Consider this information when preparing the solution. It is recommended to prepare the solution directly before the coating application after all prior steps have been completed. When coating large areas or in an assembly line, consider mixing the solution in smaller quantities rather than the total solution needed for the total area to be coated.
The first step of the solution preparation process is to calculate how much material is needed for the area that will be coated. When calculating total solution weight use 25g of solution per 10 ft2 (per 1 m2) of glass. We also recommend adding 10% to your calculated value in order to account for evaporation and the solution that remains in the containers. If applying by roller, account for roller retention by including 35g for each roller to your total weight calculation. This 35g is separate from the calculated value per 10 ft2 (per 1 m2). Do not use a roller for more than 2 hours or more than 200ft2 (20m2) of surface area (otherwise the roller will begin to harden and appearance will be affected).
Example: A window that has an a width of 2 feet and a height of 4 feet has a total of 8 feet squared that needs to be coated. If you need 25 grams of total solution for every 10 square feet, for 8 square feet:
10 ft2 glass / 25 g solution = 8 ft2 glass / x g solution
x g solution = 8 ft2 * 25 g /10g = 20 g solution
Now add 10% to that value:
x g solution * 1.10 = 1.10x g solution
1.10 * 20 g = 22 g solution
Thus, 22 grams of material are needed to coat the 8 square feet. Add the 22 grams to the 35 grams of material the roller will absorb, for a total of 57 grams in this example.
Now, to mix the 57 grams of ready-to-use material, take the following steps to determine how much Insulation solution and how much hardener you will need. Remember, once the solution is mixed you will have two hours to apply the product. We recommend you clean, mask, prime, and calculate weights prior to measuring and mixing.
The Insulation to hardener mixing ratio is 9:1 by weight, meaning that for every 9 parts of resin, 1 part hardener is needed (by weight).
Continuing this example. To calculate the mixing ratios for 57 grams of Liquid Window Insulation:
57 g *1/10 = 5.7 g hardener
57g * 9/10 = 51.3 g resin
2. Measure and Mix
Next, using the recommended material (Material L) weighing scale, measure the calculated amounts of Resin and Hardener in separate cups, then mix together. Note: some installers have very steady hand pour the hardener then the resin into a single cup.
3. Prepare Equipment
Once mixed, cover the measuring cup with aluminum foil immediately to keep contamination from falling in and to slow the hardening process. The coating solution has a pot life of 2 hours. If the coating solution has not been used within a 2-hour period, measure and mix a new solution. DO NOT use a coating solution that has been mixed over 2 hours prior to application. It is recommended to write the time of mixing on the solution container.
At this point it in necessary to double check all equipment is ready to be used.
For roller preparation, it is recommended to clean the roller with tape to remove any contamination. Cut off the edge of the roller to square the edge. This will allow for a straight edge on the final coating. After the roller has been cut and cleaned, surround the roller in aluminum foil (Material O) or a solvent resistant material that can allow for little evaporation. Pour 35g of the solution in the aluminum foil or like material and allow the roller to soak. The roller should soak for at least two minutes to allow the coating solution to penetrate the roller. This 35g will be held by the roller and should not account for in the solution being used to coat the substrate.
C. Roller Application
The roller can absorb up to an additional 65g of the liquid insulation solution in addition to the 35g used to saturate the roller – this comes to a total of 100 grams maximum capacity absorbed by the roller. For windows or sections that require more than 65g of Liquid Window Insulation, more solution must be ready to be added to the roller. In this case, assistance from another individual is helpful to pour out additional solution since application time is limited. Hold the roller at an even pressure to avoid dripping and streaking during the initial coverage of the coating area. Not enough pressure will result in a very thin coating. Too much pressure will result in drips and streaking. However, during the course of a roll if the amount of the coating solution reduces, DO NOT STOP, but instead start to apply more pressure to the roller to get the solution out of the roller. Dip the roller in solution as needed. The first roll may drip if the roller is oversaturated with the coating solution- it is important to roll over this area immediately so the drips do not cause lines or streaking in the coating. Stopping in the center of a stroke can leave a streak in the coating. Sections should be kept to a manageable area so that the coating application process can be completed in approximately 3-5 minutes total. Hotter and dryer environments result in faster hardening.
For the most uniform coating, following the recommended coating pattern:
Pass 1: Start from the top left corner to the bottom right corner.
Pass 2: Start from the bottom left corner to the top right corner.
Pass 3,4,5,6: Perimeter.
The next passes will be a vertical motions:
- from the top to the bottom of the area,
- then from the bottom to the top of the area repeatedly in a “V” pattern while slightly overlapping each roll. Avoid sliding the roller.
Next, repeat the previous “V” pattern, but horizontally.
The final passes should be vertical. Starting from the bottom and applying light pressure, roll up to the top of the area and gently lift the roller. Repeat this light rolling from bottom to the top while slightly overlapping each pass. Apply the lightest pressure to ensure good uniformity and complete coverage.
Re-work or fixing errors
If any parts of the coating are noticeably thick (these sections may appear slightly blue) rub them lightly, buffing them into the surface with very light pressure. If an adjustment needs to be made before the coating has dried, eliminate the contaminant with a small section of a KimWipe or micro-fiber cloth, and touch up the area with more coating. Small contaminants or tiny pieces of dust can be removed with tweezers.
If areas appear to be repelling the coating and showing poor adhesion, this is the result of a hydrophobic area on the glass – the following steps should be taken quickly (before setting):
- Remove coating from area with a KimWipe or micro-fiber cloth.
- Re-apply primer using KimWipe or micro-fiber cloth in a circular motion, buffing it in to remove the hydrophobic patch causing adhesion problems.
- Proceed to use the roller to re-apply solution and blend in the area with the rest.
- Use the primer solution to remove the coating in areas where it is not desired.