BACKGROUND OF THE INVENTION The present invention relates in general to a papermaking method, and more particular, to a method of forming voids in various shapes during the papermaking process, such that the pulp used for making this type of paper is reduced.
The contemporary papermaking process includes the steps of de-barking, chipping, digesting, rinsing, bleaching, and rinsing to obtain a pulp. The fibers that have not been broken down and other residues are then removed by a screening process. The screened pulp flows from the head of a papermaking machine into a moving belt of metal or plastic mesh to evenly form a paper web. The paper web is subjected to a squeezing process to remove water contained therein. After the squeezing process, drying and other subsequent processes are further performed to obtain newly made paper as shown inFIG. 1.
The newly made paper can be used as wrapping paper or processed to form the carrying bag as shown inFIG. 2. Colors or patterns are often printed on the carrying bag for commercial use. Normally, the article wrapped within a wrapping paper or the carrying bag is not visible, and the paper is typically airtight to easily ripen fruit wrapped or carried therein.
To provide aesthetic effect, some merchants will add some cutworks on the paper or puncture the paper with voids in various shapes. The voids also provide air circulation and visibility of the articles contained therein. However, it is very laborious and costly for making this type of paper, and the pulp used for making this type of paper is not reduced. Further, additional process is required for recycling of the cutaway portion of the paper.
BRIEF SUMMARY OF THE INVENTION The present invention provides a method of forming voids in various shapes during the papermaking process, such that the pulp used for making this type of paper is reduced. In addition, the labor and cost for forming voids are reduced.
The present invention provides a papermaker including a mesh having a plurality of protrusions used to screen water and fiber that has not been broken down from a pulp is also used to web the pulp into a pulp web, such that a plurality of holes is formed to extend through the pulp web. After squeezing and drying steps, a paper with a plurality of voids is formed. The voids are formed without subsequent cutting process, such that the amount of pulp used for making the paper is reduced, and the cost and labor are reduced. Alternatively, when a pulp is webbed by a conventional mesh into a pulp web, a mold having a plurality of protrusions may be used to press the pulp web, so as to form the voids in the pulp web. Thereby, voids are formed simultaneously with the paper.
These and other objectives of the present invention will become obvious to those of ordinary skill in the art after reading the following detailed description of preferred embodiments.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS These as well as other features of the present invention will become more apparent upon reference to the drawings therein:
FIG. 1 illustrates a piece of conventional paper;
FIG. 2 is an perspective view of a conventional paper product;
FIG. 3 is a process flow showing the process of making a paper product;
FIG. 4 shows a mesh including a plurality of protrusions formed thereon;
FIG. 5 shows a piece of paper including voids formed during the papermaking process;
FIG. 6 shows the process of forming a piece of paper with a plurality of voids;
FIG. 7 shows a piece of paper having another pattern of voids;
FIG. 8 shows a carrying bad fabricated by a piece of paper made with voids during papermaking process; and
FIGS. 9 and 10 show another shapes of the voids extending through the paper.
DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
Referring toFIGS. 3 and 4, the papermaking process and a mesh used for screening pulp are illustrated. The papermaker, that is, the mesh is used to make a paper with a plurality of voids at the time the paper is made. The in-situ formation of the voids reduces the amount of pulp used for making paper, and the weight of the paper. Therefore, the cost and labor for making the paper is greatly reduced. Further, the voids provide air circulation and visibility of the goods or articles contained or carried by the paper.
The papermaking method includes the steps of obtainingwood log1, debarking2, chipping3, digesting4, rinsing5, bleaching6, cleaning7 and beating8. After the above steps, additives are mixed with the pulp, and ascreening step10 is performed to screen water and fiber that has not been broken down. A mesh is then used to form a paper web. The paper web is then conveyed between two rollers for squeezing out the remaining water and to increase the density and strength of the paper instep11. After thesqueezing step11, water remaining in the paper is still high, adrying step12 is then performed to remove the remaining water. Thereby, the paper is made.
In the above process, themesh10 used for webbing includes a plurality ofprotrusions13 as shown inFIG. 4. When the webbing process is performed on the pulp, the protrusions result in voids within the paper web formed thereby. After thesqueezing step11 and thedrying step12, a piece ofpaper15 having a plurality ofvoids14 is fabricated as shown inFIG. 5.
FIG. 6 shows another method of forming the voids during papermaking process. As shown, puncturing technique is applied to form the voids after the paper web is obtained by themesh11. As shown, when the paper web is formed, amold16 including a plurality ofprotrusions17 formed thereon is used to press the pulp web. Portions of the pulp web are then removed byprotrusions17 of themold16 during the press process. After the squeezing anddrying steps11 and12, a piece ofpaper15 having a plurality ofvoids14 is thus formed.
FIG. 7 shows another method for forming voids at the time the paper is made. In this embodiment, themesh10 includes a plurality ofholes18 as shown inFIG. 7. After themesh10 is used to screen the water and fiber that has not been broken down, the portions of the pulp over theholes18 flow therethrough to form a plurality ofvoids14 in thepulp web14. Similarly, after squeezing anddrying steps11 and12, thepaper15 having a plurality ofvoids14 is formed as shown inFIG. 5.
FIG. 8 shows a carrying bag made of thepaper15 having a plurality ofvoids11 formed at the time thepaper15 was made. Formation of thevoids11 prevents the products such as ceramic glass from being scratched and broken. Further, when fruit or food is carried in the carrying bag made of thepaper15, air circulation is provided through the holes to maintain the freshness of the fruit and food. In addition, it also avoids the users to carry the wrong bags when the external features are the same.
It is appreciated that theprotrusions14 of themesh10, theprotrusions17 of themold16 and theholes18 of themesh10 are not limited to a specific shape. Various shapes (as shown inFIGS. 9 and 10) such as circular, triangular, oval, trapezium, rhombic, polygonal and rectangular, or irregular geometric can be applied.
While an illustrative and presently preferred embodiment of the invention has been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.