WATERPROOF PAPER BAG AND METHOD OF MAKING SAME

Abstract

A waterproof paper bag made of paper and a method of forming same wherein at least one side the paper has been coated with a waterproof substance. The waterproof paper bag is manufactured from a sheet of paper which has been coated with a waterproof substance so that at least an inside of the paper bag is coated with the waterproof substance, such as a biodegradable resin, or wax. A piece of waterproof paper is then cut from the sheet and is folded and a flat bottom paper bag with the waterproof coating on an inside of the bag.

Claims

1. A waterproof paper bag comprised of paper having: a bottom, a front, a back, a first side, and a second side with an open top; and the paper having a waterproof coating on an inside surface of the bottom, the front, the first side, and the second side of the paper bag.

2. The waterproof paper bag of claim 1, wherein the waterproof coating is comprised of biodegradable resin.

3. The waterproof paper bag of claim 2, wherein the biodegradable resin is comprised of starches, cellulose, and vegetable oil.

4. The waterproof paper bag of claim 1, wherein the waterproof coating is sprayed onto the paper before the paper bag is formed.

5. The waterproof paper bag of claim 2, wherein the waterproof coating is sprayed onto the paper before the bag is formed.

6. The waterproof paper bag of claim 1, wherein the waterproof coating is comprised of wax.

7. The waterproof paper bag of claim 6, wherein the waterproof coating is comprised of paraffin wax.

8. The waterproof bag of claim 6, wherein the waterproof coating is sprayed onto the paper before the paper bag is formed.

9. The waterproof bag of claim 7, wherein the waterproof coating is sprayed onto the paper before the paper bag is formed.

10. A method of making a waterproof paper bag comprising the steps of: a) obtaining a sheet of paper with a waterproof substance coated on one side thereof; b) cutting the sheet of paper into a desired dimension; c) folding the desired dimension into a rectangular tube having a front, a back, a first side, and a second side, such that the rectangular tube has a top end and a bottom end with an open space between the top end and the bottom end; d) fixing a seam along a longitudinal portion of the rectangular tube; e) folding the bottom end of the rectangular tube to form a sealed bottom of the paper bag; and f) fixing seams on the bottom of the paper bag.

11. The method of claim 10, further comprising the step of spraying the sheet of paper with a waterproof substance and allowing the waterproof substance to cure before cutting the sheet of paper into a desired dimension.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Reference may now be had to the following detailed description taken together with the accompanying drawings in which:

[0024] FIG. 1 shows a waterproof paper bag in accordance with one embodiment of the current invention;

[0025] FIG. 2 shows a sheet of paper used in manufacturing the waterproof paper bag of FIG. 1;

[0026] FIG. 3 shows a cross-section of the paper sheet of FIG. 2 which has been lined with waterproof coating;

[0027] FIG. 4 shows a piece of the sheet of paper of FIG. 2 which has been lined with waterproof coating and cut into a rectangular shape for folding and forming into the waterproof paper bag of FIG. 1;

[0028] FIG. 5 shows the piece of the sheet of paper of FIG. 4, folded substantially in half with a portion extending as a fold tab;

[0029] FIG. 6 shows the folded piece of paper of FIG. 5 with the fold tab folded over and fixed to the back side of the front of the bag;

[0030] FIG. 7 shows the folded piece of paper of FIG. 6 with the bottom end folded up and fixed to form a flat bottom; and

[0031] FIG. 8 shows the bag from a side view.

DETAILED DESCRIPTION OF THE INVENTION

[0032] FIG. 1 shows a waterproof paper bag 2 in accordance with one embodiment of the current invention. The waterproof paper bag 2 has an open top 4 and a flat bottom 6 such that the bag 2 sits upright which is ideal when the bag 2 is being filled. The waterproof paper bag 2 also has a front 8 and a back 10, a first side 12, and a second side 14.

[0033] At least the inside of the waterproof paper bag 2 is lined with a waterproof substance. Preferably, the waterproof substance is a biodegradable resin. Preferably, the biodegradable resin is a mixture comprising starches, cellulose, and vegetable oil. Alternatively, the waterproof substance can be a wax such as paraffin wax. Preferred dimensions of the bag are a height of 9 inches, width of 4 inches, and a depth of 2 inches.

[0034] FIG. 2 shows a sheet of paper 20 used in manufacturing the waterproof paper bag 2 of FIG. 1. This sheet of paper 20 has a waterproof coating on one side of the paper 20. The waterproof coating is preferably a biodegradable resin as hereinbefore described. This paper 20 can alternatively be wax paper having a wax coating on one or both sides. Preferably this sheet of paper 20 is mass produced from a roll of paper. Preferably the paper 20 is recycled paper. In one embodiment, one side of the sheet of paper 20 is coated with the waterproof substance, which is preferably sprayed onto one side of the sheet of paper 20 a conveyor system.

[0035] FIG. 3 shows a cross-section of the sheet of paper 20 in FIG. 2. As shown, there is a thin layer of waterproof substance 22 on a surface of the sheet of paper 20.

[0036] FIG. 4 shows a piece of paper 30 of the sheet of paper 20 of FIG. 2 which has been coated on one surface with a thin layer of the waterproof substance 22. The piece of paper 30 has been cut to a selected dimension with a width X, and a height Y, as shown. The dimensions X and Y are selected so that, once the piece of paper 30 is folded, the bag has the desired dimensions.

[0037] FIG. 5 shows the piece of paper 30 folded substantially in half to create a top portion 32 and a bottom portion 34. The waterproof substance coating is on the sides of the top portion 32 and the bottom portion 34 which are folded towards one another. The bottom portion 34 is slightly wider than the top portion 32, and has a piece of paper 30 extending as a fold tab 32. The fold tab 32 has a selected width Y and is subsequently folded over onto the bottom portion 34 and fixed to a back surface of the top portion 32 as shown in dashed lines in FIG. 6.

[0038] FIG. 7 shows the folded piece of paper 30 to form the waterproof paper bag 2 of FIG. 1. The first side 12 and the second side 14 are folded along a midline so that the bag 2 is flat when not opened up. This is ideal for storage and shipping. Also as shown, the bottom 6 of the bag 2 is formed by folding a first side portion 40 and a second side portion 42 towards a midline of the bag 2. Then, a back portion 44 of the back of the bag 2 having a trapezoidal share is folded towards the front of the bag 2. Finally, a front portion 46 of the front of the bag 2 also having a trapezoidal shape is toward the back of the bag 2 and is fixed to the back portion 44.

[0039] FIG. 8 shows the bag 2 opened up in a side view and standing on the flat bottom 6.

[0040] Although this disclosure has described and illustrated certain preferred embodiments of the invention, it is also to be understood that the invention is not restricted to these particular embodiments rather, the invention includes all embodiments which are functional, or mechanical equivalents of the specific embodiments and features that have been described and illustrated herein.

[0041] It will be understood that, although various features of the invention have been described with respect to one or another of the embodiments of the invention, the various features and embodiments of the invention may be combined or used in conjunction with other features and embodiments of the invention as described and illustrated herein.