Recording medium and method for producing recorded matter having three-dimensional image

A method for producing a recorded matter having a three-dimensional image, comprising the steps of:

• adding, to a recording medium including a substrate and a foaming layer being provided on the substrate and containing a foaming material which foams with heat and a binder resin, a foam-promoting liquid containing a foam-promoting component which reduces a foaming start temperature of the foaming material and water;
• and
• heating the foaming layer of the recording medium to which the foam-promoting liquid is added to cause the foaming material to foam, forming a three-dimensional image, wherein
• a contact angle of water to a surface of the foaming layer 30 seconds after the water is brought into contact with the surface of the foaming layer is 30° or more and 80° or less, and
• a ratio of a diameter of a water droplet 30 seconds after the water is brought into contact with the surface of the foaming layer to a diameter of the water droplet 0.01 seconds after the water is brought into contact with the surface of the foaming layer is 1.3 times or less.