Just like with most natural products, glues have an expiration date. You'll notice, especially with your protein and liquid water-based glues, that after they have hit their expiration date they may become moldy and unusable.
What do you do if your glue is expired?
First thing is first, if your glue has become moldy we advise against trying to "make it work".
You don't want to run expired glue, and potentially ruin your perfectly good substrates. You'll end up wasting a lot of time and money that way. If the glue is bad, the end product likely will be too.
Glue that is past the expiration date will not provide the appropriate adhesion properties and you will likely have to discard it. It's very important to make sure that you properly dispose of glue.
Expired Protein Glue
Each protein glue shipment that leaves LD Davis will contain a label on the package containing important product information. You will be able to find the glue expiration date on this label.
In most cases, protein glue is good for one year after the date it is manufactured (there are some exceptions to this - be sure to check your Technical Data Sheet).
It is worth mentioning that if your protein glue is properly stored in a cool dry place, it may last beyond the expiration date. Make sure to thoroughly check the product if it is past the expiration date to determine if there is any mold or hard glue cakes. If the glue seems compromised in any way, it is best to dispose of it.
EXPIRED LIQUID GLUE
Liquid water-based glues work a little differently when it comes to expiration dates.
Being exposed to air will shorten the life of the product, so it's best to keep these air tight until you are ready to use them. You will find the "manufactured date", but not the expiration date, on the label. The expiration date will vary depending on when you open the container.
Most liquid glues are good for 90 days after the container is opened (there are some exceptions to this - be sure to check your Technical Data Sheet).
Disposing Glues Properly
All of our raw materials and their federally mandated material safety data sheets, instruct the glue user to dispose of any excess material properly following local laws and ordinances. It's best to check with your local ordinance to confirm that you are properly disposing your glue.
Most times, the local ordinance will want to review the Safety Data Sheet for your glue product to determine how it should be disposed of.
Protein glues are typically considered non-hazardous solids that can be added to the solid waste stream without any issues.
Small amounts of liquid glue can be added to absorbent granules, like Oil-Dri, and then disposed of into the solid waste stream. Drums and totes of liquid glue will need to be picked up by a waste handling company.
If possible, we always recommend recycling your glue packaging.