What is this? It’s sticky and it doesn’t dry up. I don't think it's water.
It could be one of 2 different possibilities. The first is it could be excretions from an insect infestation. You want to check the plant over well and make sure you don’t see any bugs or scale on the orchid. Also be sure to check the surrounding orchids and make sure they don’t have any insects on them. If they are all clear than most likely you have excretions from the orchid known as orchid sap, or orchid nectar.
Orchid sap would generally be excreted by healthy plants and is common in Phalaenopsis, Cattleyas, and Oncidiums just to name a few. You may also find the sap on other orchids as well. It isn’t bad news, but it should be removed.
Removing the sap is easy. There are several ways to do this. I prefer to use a Clorox wipe and simply cleanse the sap off the leaves by gently wiping the residue from the stem or leaf. For more difficult areas to reach a small brush like a toothbrush can be a great help. Remember to be gentle. You don’t want to snap a stem or leaf while doing this.
It is important to remove the residue because it can attract pests like ants or other insects who want to benefit from the sap. Afterall the sap is sucrose (sugar). If left it could also turn brown as dust collects on it or it might even lead to sooty mold overtime.