This invention relates to novelty plastic drinking straws formed of two or more colors, with one of the colors being opaque, the straws having a flat side running the length of the straw, and to the method of making the straws.
Drinking straws formed of transparent plastic, and often curved into sinuous forms, are a popular novelty for use by children. The transparent walls of the straws allow children to watch liquid rising through the straw as the child sucks on the straw. These straws are usually circular in cross section and it is difficult to imprint a message, such as the trademark of the straw, the manufacturer of the straw, or a decorative design, along the length of the straw. Such message would be more easily printed and more visible if printed on a flat surface of the straw. At the same time, it is important to allow the straw, or at least the cross section of the straw which is not imprinted, to be largely transparent to allow viewing of the liquid rising through the straw.
This present invention is accordingly directed toward a novelty plastic drinking straw, partially transparent in cross section and partially opaque, to allow a message of the type noted above to be imprinted lengthwise along the straw on the opaque section, and more particularly to such a straw in which the opaque section is formed on a flat side running the length of the straw. The present invention is also directed toward a method of making such a straw.
A preferred embodiment of the invention, which is subsequently disclosed in detail, is formed by an extrusion apparatus having an extruding head connected to two extruders, one of which provides a generally opaque plastic and the other which extrudes substantially transparent plastic. The plastics are fed simultaneously through an extruding die which generates a tubular shape with one at least one flat side. The flat side is then imprinted with a message formed of elements such as characters extending longitudinally along the length of the tube. The straw may be bent into a desired two-dimensional or three-dimensional shape while it is still at an elevated temperature or may be cut into desired lengths which may later be reheated and bent.
Other objectives, advantages, and applications of the present invention will be disclosed in the following description of preferred embodiments of the invention. The description makes reference to the accompanying drawings, in which:
Referring to the drawings, a drinking straw formed in accordance with the present invention, generally indicated at 10 in
In an alternate configuration, illustrated in the cross section of
The presence of a flat, substantially opaque plastic side allows printing along the flat side, in the manner of 24 in
The significance of a flat side formed of substantially opaque plastic allows the imprinted words or graphics to be sharply visible against the background and to be clearly printed on the straw. The plastic of the flat imprinted side need not be totally opaque in order to provide high visibility to the printing formed on that side, thus the term “substantially opaque”. Similarly, the other sides need not be completely transparent but could be slightly translucent. The purpose of the transparent surfaces is to allow a child drinking through the straw to see the progress of the liquid through the straw, which is entertaining to children.
The imprinting 24 can be relatively short and repeated, as in the case of drinking straw 10, or it could be continuous along the flat side of the straw in alternative embodiments.
The combined extrusion, in the form of tubing 34, is then passed under a printing head 36 which imprints the required letters or graphics on the flat side formed by substantially opaque plastic of the straw material 34. Afterward the straw material 34 may be passed through a chilling chamber and possibly subjected to a blower to dry ink formed on the tubing by the printing head 36.
The imprinted tubing may then be passed into a bending machine to produce the form illustrated in
As has been noted, the bending operation could be performed in line while the section 34 is still above its glass transition temperature. The heads 42 and 44 could be disposed at an angle to the paper so as to produce three-dimensional shapes. It is critical that the shapes not have sharp bends which would inhibit free flow of liquid through the straw, but otherwise almost any shape imaginable could be employed. They could be in the form of script signatures, animal designs, or the like.