Paint cup with ventilation valve

1 . A paint cup for a paint spray gun, the paint cup comprising:

a paint container which has a vessel wall and a base,

wherein the base is made of a natural fibrous material so as to be pierceable and has a piercing point or region in order to ventilate the paint cup,

wherein the paint cup comprises a piercing spike, wherein the piercing spike is embodied in such a way that a ventilation valve for producing pressure compensation is formed by penetration of the base at the piercing point or region, and

wherein the piercing spike has retaining means for fixing the piercing spike on the paint container in a ventilation stage in which the paint cup ventilates to the atmosphere and a sealing stage in which the paint cup does not ventilate to the atmosphere,

wherein the piercing spike has at least four axially successive sections, wherein the first section is a penetration tip, the second section is a ventilation shaft section, the third section is a sealing shaft section, and the fourth section is an actuating cap,

wherein the retaining means comprises a first circumferential fixing groove arranged between the ventilation shaft section and the sealing shaft section and a second fixing groove arranged between the sealing shaft section and the actuating cap, and

wherein the first circumferential fixing groove is captured by the base to maintain the piercing spike in the ventilation stage and the second circumferential fixing groove is captured by the base to maintain the piercing spike in the sealing stage.

2 . The paint cup as claimed in claim 1 , wherein the piercing point or region is indicated optically and/or haptically.

3 . The paint cup as claimed in claim 1 , wherein the piercing spike has one or more axially extending ventilation channels.

4 . The paint cup as claimed in claim 3 , wherein the one or more axially extending ventilation channels are in the form of one or more axially extending grooves arranged on the circumference of the ventilation shaft section.

5 . The paint cup as claimed in claim 1 , wherein the piercing spike has one or more axially extending ventilation channels, which continue into one or more radially extending ventilation channels on an end face of the piercing spike.

6 . The paint cup as claimed in claim 1 , wherein the vessel wall is made of a natural fibrous material.

7 . The paint cup as claimed in claim 1 , wherein at least one of the vessel wall and the base is made of cardboard with a weight per square meter over 200 g/m 2 .

8 . The paint cup as claimed in claim 1 , wherein at least one of the vessel wall and the base is provided, at least on the inside, with a liquid-resistant coating.

9 . The paint cup as claimed in claim 8 , wherein the liquid-resistant coating includes at least one of plastic and aluminum.

10 . The paint cup as claimed in claim 1 , wherein at least one of the vessel wall and the base is single-ply, two-ply or three-ply cardboard.

11 . The paint cup as claimed in claim 1 , wherein an end of the paint cup facing the paint spray gun has an outlet opening for connection to the paint spray gun or for connection to an adapter for connection to the paint spray gun.

12 . The paint cup as claimed in claim 1 , wherein the natural fibrous material is a cellulose-based fibrous material.

13 . A method for using the paint cup as claimed in claim 1 , the method comprising piercing the base to form a ventilation valve.