Device for evaporating volatile substances
The invention refers to a device for evaporating volatile substances comprising: a container of a liquid volatile substance, and a vapour permeable membrane ( 1 ) and a thermoplastic porous or fibrous laminate ( 2 ) bonded together. Said container is closed at its opening by said vapour permeable membrane ( 1 ) and the fibrous laminate ( 2 ), wherein the fibrous laminate ( 2 ) is welded to the thermoformed part of the container.
1. A device for evaporating volatile substances comprising:
a first portion comprising a container having a volume adapted to hold a liquid volatile substance, the first portion comprising a peripheral part and an opening that provides access to the volume, the first portion further comprising a first layer of a thermoformed material and a second layer of a sealing material, the second layer of the sealing material having a first surface located on the peripheral part and a second surface within the volume, and
a second portion comprising a vapour permeable membrane and a fibrous laminate bonded together, wherein the fibrous laminate is a reinforcing substrate adapted to reinforce the vapour permeable membrane,
wherein the fibrous laminate of the second portion is welded to the peripheral part of the first portion,
wherein said first portion is closed at the opening by said second portion, thereby enclosing the volume,
wherein the fibrous laminate extends through the opening, is in contact with the second surface of the sealing material within the volume, and fills a part of the volume,
wherein the liquid volatile substance is disposed in the volume,
wherein the fibrous laminate is arranged in contact with the liquid volatile substance so that the liquid volatile substance evaporates through the vapour permeable membrane.
2. The device according to claim 1 wherein the fibrous laminate is selected to have a melting point lower than the melting point of the vapour permeable membrane.
3. The device according to claim 1 wherein the vapour permeable membrane is an elastomeric monolithic membrane.
4. The device according to claim 3 wherein the elastomeric monolithic membrane comprises a material selected from the group comprising: an elastomeric polyester, polyamide block ether, polyurethane, and polyolefin elastomer.
5. The device according to claim 1 wherein the fibrous laminate is selected from the group comprising: non woven material, polyolefin non woven, polypropylene or polyethylene non woven.
6. The device according to claim 5 wherein the fibrous laminate includes a non woven material made of fibers with a polypropylene core and a polyethylene shell.
7. The device according to claim 1 wherein the vapour permeable membrane and the fibrous laminate are laminated together by thermally and mechanically bonding these two elements.
8. The device according to claim 1 wherein the vapour permeable membrane and the fibrous laminate are laminated together by applying in a discrete form an adhesive in between.
9. The device according to claim 1 wherein the vapour permeable membrane and the fibrous laminate are laminated together by applying in between of a continuous layer of an adhesive material which is permeable to the volatized substances.
10. The device according to claim 1 wherein the fibrous laminate is a polyethylene spunbound non woven having a grammage within the range 50 to 150 g/m2.
11. The device according to claim 1 wherein the container is a thermoformed container made of polyethylene terephthalate/polyethylene vinyl alcohol/polyethylene.
12. The device according to claim 1 wherein a removable barrier film is provided on the outer surface of the vapour permeable membrane.