| 摘要 |
The present invention relates to a process for producing, by dry means, pure expanded cork-bark agglomerate in the form of sheets coated with films and to sheets of pure expanded cork-bark agglomerate with coating films obtained by means of the said process, which comprises the stages of introduction of a specific quantity of cork- bark granulate with a suitable particle size into a mould with the internal dimensions of the final sheet of pure expanded cork-bark agglomerate, previously equipped, in its base, with a first coating film that is preferably impermeable and resistant to the baking temperature, and the positioning of a second, top coating film, that is preferably impermeable and resistant to the baking temperature, and closure of the mould with a cover fixed in a specific position depending on the thickness of the sheet; baking of the cork-bark granulate in an oven at a suitable temperature for expansion and exudation of the cork bark, and for a period of time necessary for the action of the heat to affect the entire mass of the granulate and to give rise to its agglomeration; cooling of the mould with the granulate; and removal from the mould of the sheet of pure expanded cork-bark agglomerate, in which the mould is opened and the sheet removed, already with the final thickness and with the surface covered by the coating films used, that adhere perfectly. Although the process described relates to the production of straight sheets of uniform thickness, the same process is applicable to the production of curved sheets of uniform or non-uniform thickness. The present invention is applicable in the cork-bark industry.
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