Method and Device for Making Synthetic Stoppers

Abstract

A method for marking synthetic stoppers comprising: a first step for producing a synthetic stopper, in which, during the process for manufacturing the synthetic stopper, an activator is inserted, the activator being mixed with the synthetic material with which the synthetic stopper is produced, and a second step for marking the synthetic stopper, in which a light beam strikes the synthetic stopper and is absorbed, generating heat, which generates a thermal reaction on the activator, and the thermal reaction degrades the activator proximate to the surface of the synthetic stopper, so that the activator assumes a different color in contrast with the color of the surface of the synthetic stopper, so as to make the intended marking visible.

What is claimed is: 
     
         1 - 15 . (canceled) 
     
     
         16 . A method for marking synthetic stoppers, comprising a first step for producing a synthetic stopper, in which, during the process for manufacturing said synthetic stopper, an activator is inserted, said activator being mixed with the synthetic material with which said synthetic stopper is produced, and a second step for marking the synthetic stopper, in which a light beam strikes said synthetic stopper and is absorbed, generating heat, said heat generating a thermal reaction on said activator, said thermal reaction degrading said activator proximate to the surface of the synthetic stopper, so that said activator assumes a different color in contrast with the color of said surface of said synthetic stopper, so as to make the intended marking visible. 
     
     
         17 . The method for marking synthetic stoppers according to  claim 16 , wherein the synthetic stopper is made of polyethylene, polypropylene, EVA, elastomers (SEBS, SBS, SEPS, or other suitable elastomers) and preferably made of a compound of polyethylene/EVA, polyethylene/SEBS, polyethylene/EVA/SEBS. 
     
     
         18 . The method for marking synthetic stoppers according to  claim 16 , wherein the light beam is obtained from a light source which emits said light beam with a wavelength ranging from 200 to 1064 nm, a power ranging from 2 to 30 W, and a frequency ranging from 10 to 100 kHz. 
     
     
         19 . The method for marking synthetic stoppers according to  claim 18 , wherein the light beam is obtained from a light source which emits said light beam with a wavelength of 532 nm, a power from 3 to 10 W, and a frequency from 20 to 65 kHz. 
     
     
         20 . The method for marking synthetic stoppers according to  claim 18 , wherein the light source is a double- or triple-frequency excimer laser or a YAG laser or a CO 2  pulse laser. 
     
     
         21 . The method for marking synthetic stoppers according to  claim 16 , wherein the activator is a pigment. 
     
     
         22 . The method for marking synthetic stoppers according to  claim 21 , wherein the pigment is selected among kaolins, chalks, alumina, phyllosilicates, mica, antimony oxide III, metallic pigments, pearl luster pigments, carbon black and mica coated with metallic oxides. 
     
     
         23 . The method for marking synthetic stoppers according to  claim 22 , wherein the pigment is selected among pigments based on oxides or dioxides of metals. 
     
     
         24 . The method for marking synthetic stoppers according to  claim 23 , wherein said pigments are titanium dioxide, iron oxide, chromium oxide, nickel titanate. 
     
     
         25 . A device for performing the method of  claim 16 , comprising a hopper provided with a vibration unit, a conveyor belt, which advances at a preset speed adjusted by a step motor, a handling unit provided with at least one grip hand, and a laser unit for performing the second step for marking the synthetic stopper. 
     
     
         26 . The device according to  claim 25 , wherein the handling unit comprises two grip hands. 
     
     
         27 . The device according to  claim 26 , wherein the grip hand is capable of picking up four synthetic stoppers at each pick-up action. 
     
     
         28 . The device according to  claim 27 , wherein the grip hand is capable of rotating about itself through a selected angle. 
     
     
         29 . A synthetic stopper obtained with the method for marking synthetic stoppers according to  claim 16 . 
     
     
         30 . The synthetic stopper according to  claim 29 , wherein the second step for marking said synthetic stopper is performed by means of the device according to  claim 25 .