1. A process for forming a silicon-containing reaction product comprising the steps of:
(a) introducing silicon tetrachloride into a reactor vessel containing molten sodium metal, in which the level of molten sodium is controlled to remain within predetermined processing parameters whereby the sodium is always in stoichiometric excess to the silicon tetrachloride;
(b) separating the reaction products comprising a mixture of silicon metal, sodium chloride, and sodium metal, from the sodium metal in the reactor vessel; and
(c) removing from the silicon metal a sufficient quantity of the non-silicon products that would be detrimental to the performance of the silicon metal as a semiconductor for use in photovoltaic devices used to generate electric power.
2. The process of claim 1, wherein silicon tetrachloride is introduced into the vessel as a liquid.
3. The process of claim 1, wherein the level of sodium in the vessel is maintained by an automated process within a set of process parameters that are controlled automatically.
4. The process of claim 2, wherein the level of sodium in the vessel is maintained by an automated process within a set of process parameters that are controlled automatically.
5. The process of claim 1, wherein the silicon-containing reaction product is separated from the sodium under an inert atmosphere.
6. The process of claim 2, wherein the silicon-containing reaction product is separated from the sodium under an inert atmosphere.
7. The process of claim 2, wherein at least half of the sodium contained in the reaction product is removed by heating the reaction product in an inert atmosphere to a temperature greater than 800\xb0 C.
8. The process of claim 7, wherein the heating process is repeated to further purify the silicon metal.
9. The process of claim 2, wherein the silicon metal has an average particle size greater than 10 microns.
10. The process of claim 2, wherein the silicon metal has an average particle size greater than 100 microns.
11. A reaction product formed by the process of claim 1, comprising principally elemental silicon metal, sodium chloride, and metallic sodium, in which the mass fraction of metallic sodium is greater than 0.1%.
12. A reaction product formed by the process of claim 1, comprising principally elemental silicon metal, sodium chloride, and metallic sodium, in which the mass fraction of metallic sodium is greater than 1%.
13. A process to reduce the mass fraction of metallic sodium in the product of claim 11 or 12, comprising the step of heating the product to a temperature above the boiling point of sodium in an inert atmosphere, and thereby reducing the mass fraction of metallic sodium in the product.
14. A metallic silicon composition produced by the removal of the sodium chloride and sodium metal from the product of either of claim 11 or 12, in which the metallic silicon is at least 99.999% pure and is suitable for the manufacture of photovoltaic devices used to generate electric power.
15. An ingot of metallic silicon produced by the vacuum melting of a metallic silicon composition of claim 14, in which the metallic silicon is suitable for the manufacture of photovoltaic devices used to generate electric power.
16. A metallic silicon composition produced by the removal of the sodium chloride and sodium metal from the product of either of claim 11 or 12, in which the metallic silicon is at least 99.9999% pure and is suitable for the manufacture of photovoltaic devices used to generate electric power.
17. An ingot of metallic silicon produced by the vacuum melting of a metallic silicon composition of claim 16, in which the metallic silicon is suitable for the manufacture of photovoltaic devices used to generate electric power.
18. A photovoltaic device produced from an ingot of metallic silicon of either of claim 15 or 17.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A carton for shipping and storing a quantity of cut sheets of paper, comprising:
a carton base portion having a bottom wall, opposed upstanding front and back walls and opposed upstanding end walls, each joined along a bottom edge to a respective edge of the bottom wall, and an open top;
a lid telescopically engaged over the open top, said lid having a top wall with depending end flanges, a depending back flange foldably connected to the lid top wall and attached to the carton back wall, and a depending front flange, said depending front flange comprising a tear strip having a longitudinal axis and being defined by two spaced apart parallel rows of successive straight inclined cut lines wherein the parallel rows of successive straight inclined cut lines being symmetrical with one another with respect to the longitudinal axis, the tear strip includes a tab which upon tearing moves in direction of convergence of the inclined cut lines, each of the inclined cut lines having an outer beginning end and an inner terminal end, whereby tearing propagates inwardly along a cut line from its outer beginning end to its inner terminal end and then outwardly to the beginning end of a successive cut line, said cut lines having a length (K) between the beginning and terminal ends, and the terminal end of one cut line being spaced from the beginning end of a succeeding cut line by a distance (D) as measured in a direction parallel to the longitudinal axis of the tear strip, wherein the ratio of DK is from 1:1 to 4:1;
said base portion front wall being unsecured to adjoining end walls and being pivotable about its bottom edge downwardly and away from the carton to an open position when the lid is moved upwardly away from said front wall, thereby exposing the cut paper at the top and one side to permit easy access to paper contained in the carton for rapid unloading of the paper from the carton;
said front wall having inwardly turned tuck-in flaps on opposite ends thereof which tuck into the carton in contiguous, parallel, overlapping relationship with adjacent end walls when said front wall is in closed position; and
said inwardly turned glue flaps being on opposite ends of said lid front flange and said lid back flange, said glue flaps on said lid front flange being attached to respective said lid end flanges, and said glue flaps on said lid back flange being free of attachment to said lid end flanges and wherein said glue flaps on said lid back flange are attached to respective said base portion end walls.
2. The carton as claimed in claim 1, wherein the ratio of DK is from 1:1 to 3:1.
3. The carton as claimed in claim 1, wherein the ratio of DK is from 2:1 to 3:1.
4. The carton as claimed in claim 1, wherein the incline cut lines diverge at perforation angles ranging from 30\xb0 to 50\xb0 degrees with respect to the longitudinal axis of the tear strip.
5. The carton as claimed in claim 1, wherein the incline cut lines diverge at a perforation angle of 45\xb0 degrees with respect to the longitudinal axis of the tear strip.
6. The carton as claimed in claim 1, further comprising a handle affixed to said lid to facilitate carrying of said package.
7. The carton as claimed in claim 1, wherein:
a bottom edge of said lid back flange and a bottom edge of said glue flaps on said lid back flange are attached to said base portion back wall and end walls, respectively.
8. The carton as claimed in claim 1, wherein:
a glue strip extends along a bottom edge of said lid front flange, said glue strip being attached to said base portion front wall.
9. The carton as claimed in claim 1, wherein:
the tuck-in flaps on said base portion front wall are relatively narrow so that they may be moved into and out of the carton without unduly disturbing the contents of the carton.
10. The carton as claimed in claim 1, wherein:
said lid top wall is foldably attached to said lid back flange along a fold line, and said lid pivots upwardly about said fold line.
11. The carton as claimed in claim 10, wherein:
said lid is attached to said base portion only by attachment of said lid back flange to said base portion back wall, attachment of said lid back flange glue flaps to said base portion end walls, and attachment of said glue strip to said base portion front wall.
12. A blank for making a lid portion of a carton for shipping and storing a quantity of cut sheets of paper, comprising:
a rectangular lid top wall panel;
opposite lid end flange panels foldably attached to opposite ends of said top wall panel;
a lid back flange panel foldably attached to a back edge of said top wall panel;
glue flap panels foldably attached to opposite side edges of said back flange panel;
a lid front flange panel foldably attached along one edge to a front edge of said top wall panel, the front flange panel comprising a tear strip having a longitudinal axis and being defined by two parallel spaced apart rows of successive inclined cut lines wherein the parallel rows of successive straight inclined cut lines being symmetrical with one another with respect to the longitudinal axis, the tear strip includes a tab which upon tearing moves in direction of convergence of the inclined cut lines, each of the inclined cut lines having an outer beginning end and an inner terminal end and a length (K) between the beginning and terminal ends, the terminal end of one cut line being spaced from the beginning end of a succeeding cut line by a distance (D) as measured in a direction parallel to the longitudinal axis of the tear strip, wherein the ratio of DK is from 1:2 to 4:1;
glue flap panels foldably attached to opposite side edges of said front flange panel, said glue flaps being on opposite ends of said lid front flange and said lid back flange, said glue flaps on said lid front flange being attached to respective said lid end flanges, and said glue flaps on said lid back flange being free of attachment to said lid end flanges; and
a glue strip panel removably attached by a tear strip to an edge of said front flange panel opposite said one edge.
13. A lid for placement over an open end of a container to close the open end, said lid comprising:
a lid top wall having an opening therethrough and depending front and back flange panel and end flange panel; the front flange panel comprising a tear strip having a longitudinal axis and being defined by two parallel rows of successive inclined straight cut lines wherein the parallel rows of successive straight inclined cut lines being symmetrical with one another with respect to the longitudinal axis, the tear strip includes a tab which upon tearing moves in direction of convergence of the inclined cut lines, each of the inclined cut lines having an outer beginning end and an inner terminal end and a length (K) between the beginning and terminal ends and further being spaced apart by a distance (D) as measured in a direction parallel to the longitudinal axis of the tear strip, wherein the ratio of DK is from 1:2 to 4:1;
an insert panel beneath said top wall, said insert panel having an opening therethrough in alignment with the opening through the top wall; and
a flexible strap attached at opposite ends to a base plate beneath said insert panel, said strap projecting through said aligned openings in said insert panel and top wall and forming a carry handle and wherein glue flaps are on opposite ends of said front flange, said glue flaps attached to said end flanges, and glue flaps are on opposite ends of said back flange, said glue flaps being free of attachment to said end flanges.