How To Properly Cure Your Garment When Using Plastisol Ink

A problem that most silkscreen/screen printers have and a question we get asked a lot is “Why is my plastisol ink coming off during the wash?"

The cause of this problem is most likely due to the fact that the ink is not cured properly. Plastisol ink needs to cure at a minimum temperature of 320º F for at least one minute. This allows the molecules to properly fuse to each other as well as to the fabric.

There are many variables that can cause problems with ink curing. Air temperature and humidity are major issues, so be sure to dry your ink in a safe controlled environment. Make sure that the ink reaches 320º F in order to cure, not just the garment that you are printing on. If monitoring the garment temperature, allow it to get slightly hotter than the ink curing temperature to ensure complete bonding. In colder weather you may need to increasing the dryer temperature, or allowing the ink to pass through a bit longer than one minute.

"Why does the plastisol ink print crack on the garment after the first wash?"

The plastisol was not cured properly if the ink is cracking. It could have been the temperature on the dryer being too high, or the time allowed to dry was too long.

"What type of affordable dryer is best to cure plastisol?"

The best dryer to properly cure garments is a conveyer dryer like the BBC Little Buddy Dryer or the Ranar Scamp Dryer. Ranar manufactures the DX200 Scamp T-Shirt Dryer, which is a conveyor dryer and one of the best options on the market in terms of price and versatility. It's available in 120 or 220 volt, it has many features that other manufacturers don't offer: adjustable heater height, temperature, belt speed, and a removable oven hood for curing caps. Whether you're silk screening t-shirts, sweats, hoodies, jackets or hats. This conveyor dryer is 24" wide 60" long with a 18" inch wide belt. With production rates of 50 to 65 pieces per hour screen printed with plastisol ink. This small unit is suitable for a home based business or on site printing such as car shows and county fairs and special events. Portable enough to run with a small generator.

Flash Dryers like the BBC Industries Afford-A-Flash is a more affordable option where the dryer just hovers over the garment until you move it.

A heat gun like the Master Heat Gun is also another options. This option is also affordable, but probably the worst of the 3 types of dryers for plastisol. Your plastisol needs to be cured evenly and with a heat gun there's no way to know if you are over-curing certain areas, or under-curing as you move the heat gun over the garment.

"What is the best way to determine the temperature of my plastisol ink as I cure it?"

There are two options to tell the temperature of your ink. One, is to use a heat gun (Mini IR Thermometer) that has a laser pointer for easy targeting and the other is Thermolabels. Thermolabels are formulated to react within a few seconds when the rated temperature is reached. As each section of a label reaches its rated temperature, that section responds with a sharply defined color change from white to black leaving the printed temperature clearly visible.

~ When dealing with plastisol the conditions, temperature, time and garment all make a difference. Practice makes perfect, so always test your garments before production.

~Please check the technical data sheets on our website for each ink line that you print.