Preform and container with variable transmittances
The invention relates to a preform intended for forming containers by blow molding or stretch-blow molding, the preform being made of plastic material including at least one additive giving the plastic material the property of at least partially filtering the visible light spectrum, the preform comprising a wall forming a hollow body, said one or more additive(s) giving the plastic material the property of at least partially allowing the passage of light in the infrared spectrum.
1 . An opaque preform intended for forming containers by blow molding or stretch-blow molding, the preform comprising:
a hollow body being made of a plastic material including at least one additive giving the plastic material the property of at least partially filtering the visible light spectrum, the hollow body comprising a wall comprising a thickness of about 1 mm to about 5 mm that is between about 4-50 times greater than a thickness of a wall of the container that is formed from the preform, characterized in that said one or more additive(s) give the plastic material the property of at least partially allowing the passage of light in the infrared spectrum, and in that the preform wall has, under electromagnetic radiation emitted perpendicular to the preform wall,
transmittance in the visible spectrum, that is substantially equal to 0% in the wavelength range of 350 nm to 520 nm; and
transmittance in the infrared spectrum within a transmittance range extending between a threshold transmittance and an upper transmittance, for at least one wavelength within the range of 700 nm to 2250 nm, the threshold transmittance being equal to 5% and the upper transmittance being equal to 70%.
2 . The preform as claimed in claim 1 , wherein the transmittance in the infrared spectrum is within the transmittance range for a wavelength of 1130 nm.
3 . The preform as claimed in claim 1 , wherein the threshold transmittance equals 8%.
4 . The preform as claimed in claim 1 , wherein the upper transmittance equals 50%.
5 . The preform as claimed in claim 1 , wherein the plastic material also comprises at least one colorant.
6 . The preform as claimed in claim 1 , wherein the thickness of the wall of the hollow body is within the range of 1 mm to 2 mm.
7 . The preform as claimed in claim 1 , wherein the plastic material comprises one or more additives forming a barrier against radiation below 350 nm.
8 . The preform as claimed in claim 1 , wherein the transmittance in the infrared spectrum is within the transmittance range at wavelengths within the range of 950 nm to 1400 nm.
9 . The preform as claimed in claim 1 , wherein the threshold transmittance equals 10%.
10 . The preform as claimed in claim 1 , wherein the upper transmittance equals 20%.
11 . The preform as claimed in claim 1 , wherein the transmittance in the infrared spectrum is within the transmittance range at wavelengths within the range of 750 nm to 1400 nm.
12 . The preform as claimed in claim 11 , wherein the transmittance in the infrared spectrum is within the transmittance range for a wavelength of 1130 nm.
13 . The preform as claimed in claim 11 , wherein the threshold transmittance equals 8%.
14 . The preform as claimed in claim 11 , wherein the upper transmittance equals 50%.
15 . The preform as claimed in claim 1 , wherein the transmittance in the infrared spectrum is within the transmittance range for one wavelength or within a spectrum of wavelengths within one of the following ranges:
1110-1160 nm;
1390-1450 nm;
1610-1650 nm;
1675-1700 nm;
1880-2100 nm; and
2170-2230 nm.
16 . The preform as claimed in claim 15 , wherein the transmittance in the infrared spectrum is within the transmittance range for a wavelength of 1130 nm.
17 . The preform as claimed in claim 15 , wherein the threshold transmittance equals 8%.
18 . The preform as claimed in claim 15 , wherein the upper transmittance equals 50%.
19 . The preform as claimed in claim 1 , wherein the transmittance measured on a wall of the container for which said preform is intended is less than 5% within the wavelength range of 350 nm to 520 nm, whereby the transmittance of the wall of the preform in the visible spectrum is considered to be substantially equal to 0%.
20 . The preform as claimed in claim 19 , wherein the transmittance measured on a wall of said container is less than 0.5%, within the wavelength range of 350 nm to 520 nm.
21 . An opaque preform intended for forming containers by blow molding or stretch-blow molding, the preform comprising:
a hollow body formed from plastic material comprising at least one additive giving the plastic material the property of at least partially filtering the visible light spectrum, the preform comprising a wall forming the hollow body, the preform wall comprising a first thickness of about 1 mm to about 5 mm that is greater than a second thickness of a wall of the container, wherein one or more additive(s) give the plastic material the property of at least partially allowing the passage of light in the infrared spectrum, and in that the preform wall has, under electromagnetic radiation emitted perpendicular to the preform wall, transmittance in the visible spectrum that is substantially equal to 0% in the wavelength range of 350 nm to 520 nm, and transmittance in the infrared spectrum within a transmittance range extending between a threshold transmittance and an upper transmittance, for at least one wavelength within the range of 700 nm to 2250 nm, the threshold transmittance being equal to 5% and the upper transmittance being equal to 70%.
22 . An opaque preform for protecting the degradation of milk's riboflavin, the preform intended for forming containers by blow molding or stretch-blow molding, and further being filled with milk comprising the riboflavin, the preform comprising:
a hollow body formed from plastic material comprising at least one additive giving the plastic material the property of at least partially filtering the visible light spectrum, the preform comprising a wall forming the hollow body and defining a preform wall thickness of about 1 mm to about 5 mm, the container that is formed by the preform comprising a container wall thickness, wherein the preform wall thickness is greater than the container wall thickness, wherein one or more additive(s) give the plastic material the property of at least partially allowing the passage of light in the infrared spectrum, and in that the preform wall has, under electromagnetic radiation emitted perpendicular to the preform wall, transmittance in the visible spectrum that is substantially equal to 0% in the wavelength range of 350 nm to 520 nm, and transmittance in the infrared spectrum within a transmittance range extending between a threshold transmittance and an upper transmittance, for at least one wavelength within the range of 700 nm to 2250 nm, the threshold transmittance being equal to 5% and the upper transmittance being equal to 70%.