Patent Application
20160194829
Not Applicable
The present invention relates to a process for preparing a paper pulp composition wherein the pulp is readily moldable and, upon curing, is structurally rigid and weather resistant. More particularly, the invention relates to a process for pulping paper into a composition suitable for use as recycled paper, craft items, picture frames, tiles, crown molding, furniture and other products.
The general concept of recycling paper is well known and a variety of methods exist for recycling paper and generating products from that paper. Generally, recycled paper lacks the structural integrity, rigidity and stability of the original paper incorporated into the recycled products. Moreover, the processes for recycling, or reclaiming, paper can be expensive and can require the use of a variety of expensive and caustic chemicals.
It is also generally known to use wet or pulped process papers combined with an adhesive such as polyvinyl acetate based glue or a starch for a variety of purposes, for example, as arts and crafts material. These processes are generally known as “papier-mâché” processes. The resulting products are generally fragile, are unstable and will degrade over time, are limited in stability by the integrity of the original paper and the effectiveness of the recycling process. Untreated, the products will develop mold and commonly will rot from the inside out. The processes heretofore known generally result in a finished product which is structurally weak, quickly degrades and is not suitable for any load bearing applications. It is common to lay the papier-mâché over a frame to lend strength to the end product or to otherwise provide supplementary supporting members to the product.
The current invention overcomes the limitations of the known processes and results in a pulped paper product that is rigid, highly stable, is weather resistant and has structural rigidity substantial enough to bear moderate loads. Moreover, the process is easy, inexpensive and safe in comparison to many previously known methods for creating recycled paper products.
The present invention provides a paper pulping process which results in a recycled paper product that is stable, long-lasting and rigid enough to provide moderate load bearing capabilities. The process results in a pulp that is readily moldable and can be used in a variety of applications. For example, the resultant pulp can be molded into picture frames, crown molding, Christmas ornaments, candle holders, art paper, panels, tile, or dimensional products. The dimensional products can then be used to manufacture articles including furniture such as bookshelves, chairs, tables and the like. The preferred formulation also results in manufactured paper products capable of withstanding water exposure and weather allowing the creation of outdoor furniture. Moreover, the process is generally easy to perform and results in consistent and predictable end products.
The inventive process and product disclosed herein was originally designed for use by organizations providing services to individuals with physical and mental limitations. The process is easy to achieve and safe to perform with highly predictable results. Recycled paper, preferably office waste, is gathered for use in the process and product. After processing, the resultant paper product can then be used for a variety of purposes. For example, in rehabilitation services or organizations providing services to those with disabilities, the resultant product can be used to make arts and crafts that can then be offered for sale. Unexpectedly, as the process described herein was derived, it became apparent that the process and product could be used in a variety of other applications as further disclosed herein.
The process generally includes combining a raw paper product, preferably recyclable paper such as newspapers, office paper and office waste materials and water to form a wet mix. Portland type 1 (which is high in calcium aluminate), fly ash silicates (pozzolanic cement), Silica, Hydrated Lime (known as Mason's Lime), Perlite (expanded silicate) and Sodium Citrate, are combined to form a dry mix. The dry mix is added to the wet mix and polyvinyl alcohol is added and mixed to form a slurry. The action of mixing the ingredients, plus the addition of polyvinyl alcohol and several optional dry ingredients forms the slurry into a pulp. to the high calcium aluminate content of the Portland type 1 forms CaOH2 (lye) which naturally results in a neutral or white color end product and eliminates the decomposition of the wetted paper common in paper pulping processes. The resulting pulp can be molded and cured in a relatively short time. For example, the product can be troweled in to picture frame molds and then dried at approximately 85-90 degrees Fahrenheit over a period of time. Generally, the product can be handled within 24 hours and sanded and finished within 48 hours. The products do continue to harden over a period of days due to the ongoing loss of moisture. The resulting picture frame, or other product, is rigid, can be painted, tinted or varnished. Further, the products are rigid and stable enough to fasten with common fasteners, such as screws and nails.
To increase rigidity and stability of the final product a stabilizer may be added to the slurry. While several stabilizing products can be used, such as sulfonated melamine formate, the preferred stabilizer is calcium lignosulfonate.
These particular objects and advantages may apply not only to the embodiments disclosed herein, but may apply for other uses and processes as well and thus are not limited by the scope of the claims herein.
The inventive process generally uses waste paper products, such as newspaper and office paper waste to create a stable paper pulp that is moldable and colorable for use in a variety of applications after it cures. Applications may include manufacturing picture frames, crown molding or other three dimensional objects by molding the pulp in prepared molds. The pulp can also be used to generate recycled paper for card stock and the like. Additionally, the pulp can be molded in to dimensional structures, such as 2×4 inch “boards” which can then be manufactured into load bearing furniture, for example bookshelves, tables and the like. The formulation disclosed herein is suitable for creating products that can withstand exposure to water and weather so that outdoor furniture, planters and the like are suitably manufactured from the pulp..
Creating the pulp composition includes mixing raw paper product with water to form a wet mixture. Dry ingredients, including Portland Type 1, fly ash (Class C), silica, hydrated lime, perlite, and sodium citrate are combined to form a dry mixture. The wet and dry mixtures are combined and polyvinyl alcohol is added and mixed to create a slurry. For clarification, the references to calcium aluminate refer to the calcium aluminate content of Portland Type 1, the common name of the product preferred, and is used here to differentiate the product from calcium carbonate (marble dust) and calcium sulfate (plaster) which are sometimes used in paper pulping processes. The high calcium aluminate content of the Portland Type 1 acts as a sanitizing agent to diminish the potential for the development of mold and to neutralize odor causing bacteria. Foul smells that normally develop during paper pulping processes, primarily during and after curing of the paper pulp is eliminated by the calcium aluminate content. And a stabilizing agent, such as calcium lignosulfonate can be added to enhance the overall stability and strength of the finished products. The resulting end product is mold resistant and will not rot or degrade as quickly as traditional papier-mâché compositions.
The raw paper materials are collected preferably from waste newspaper and office paper waste and cross shredded to create small paper particles. The paper and water are mixed together in a commercially available mixer for at least 20 minutes to create a wet mix. Dry ingredients are blended together separate from the paper and water slurry to form a dry mix. The dry mix is incorporated into the wet mix for about 10 minutes to create a slurry. Polyvinyl alcohol is added to the slurry and mixed to create the pulp. Additional ingredients such as strengthening agents can be added. The pot life, or working time, of the pulp is about 70 minutes until the mix becomes noticeably drier and stiffer.
During processing, the mixer may be covered to reduce the loss of liquid ingredients and to increase water retention throughout the mixing process. It is preferred that the composition is continuously mixed to achieve a complete pulp of the paper and to result in a uniform and consistent slurry of all of the ingredients.
The preferred materials include high calcium aluminate cement, preferably Portland Type 1 which is generally available in a variety of markets. This product acts as the main binding material for the end solution. Calcium aluminate is a mineral derived from calcium oxide and aluminum oxide combined under heat and in the form of “calcium aluminate cement” develops strength faster and cures faster than common limestone-based cements such as Portland. Fly ash is a by-product of flue gases combustion and is also readily available on the market in various forms. The preferred “Class C” fly ash is produced as a by-product of burning coal. When exposed to water, Class C fly ash hardens and gets stronger over time and is sometimes substituted for a mixture of Portland cement and sand. Here, the calcium aluminate and expanded silicate combine with and embed into the naturally occurring pores in the waste paper and adds to the overall strength of the end product. The Class C fly ash absorbs residual CaOH from the calcium aluminate and forms calcium silicate which decreases product shrinkage and adds strength to the materials. Perlite is a form of obsidian characterized by spherlulites formed by cracking of volcanic glass during cooling. It is often used as insulation and is readily available. The soluble polyvinyl alcohol acts as an emulsifier and binding agent to combine all of the fiber materials and adheres the calcium aluminate to the paper fibers. Hydrated lime, or calcium hydroxide, increases the “slump” of the pulp and allows for deeper casting of the product. It also increases the firmness of the product and allows product to be easily removed from molds. Sodium citrate acts as an acid regulator and emulsifier for oils; it may be added to extend the pot life or working time for the slurry. Addition of sodium citrate may extend the working life by about 30 minutes.
It may be beneficial to add a stabilizing ingredient or plasticizer to the slurry to further strengthen the finished product. The addition of a small amount of calcium lignosulfonate decreases water in the slurry and acts as a static charge neutralizing compound to statically charged materials with loose ionic bonding, such as the calcium aluminate. Adding this product allows less water to be used but enhances workability of the slurry. Generally, the calcium lignosulfonate will comprise less than 1% by volume of the slurry. The preferred amount will be between 0.3% and 0.6% by volume.
The preferred pH of the product is approximately 11 during mixing of the ingredients but rapidly decreases to about 10.5 pH over a month. The fly ash content continues to lower pH as the products “cure” and eventually the final product stabilizes near 9.5 pH. The preferred polyvinyl alcohol is provided by Sekisui and is the PVOH 205S which is a water soluble polyvinyl alcohol.
It is also possible to tint or color the paper pulp prior to curing. During the step of mixing the ingredients, tinting materials such as paint, solid colors, varnishes and the like can be added so that the finished product is uniformly colored. Additional materials such as gold leaf, silver beads or other highlighting materials can be added during mixing so that the product is “decorated”. This is particularly useful when the pulp is used to create picture frames, crown molding and the like.
The general formulation of the composition of the paper pulp product described herein is shown in Table 1. The preferred composition is approximately 20% -22% raw paper that has been cross-cut or otherwise shredded, approximately 21% -24% Portland Type 1, approximately 13% -16% Class C fly ash, approximately 3%-6% hydrated lime, approximately 2% -4% perlite, approximately 0.5% -2% polyvinyl alcohol and approximately 30% -40% water. The addition of approximately 0.2% -0.5% calcium lignosulfonate increases product strength and increases workability of the solution at low water ratios. Further, the addition of approximately 0.01% -0.03% sodium citrate extends the pot life of the solution.
The composition is mixed for at least 30 minutes to achieve complete pulp of the paper with uniform blending of all of the ingredients. A preliminary mix of just the paper and water creates a wet mix and is stirred for about 20 minutes is preferred. The resulting wet mix can be stored for a period of time until needed. The dry ingredients, including at least the Portland Type 1, fly ash, and hydrated lime are combined to form a dry mix. Once the dry ingredients are fully integrated, they are added to the wet mix to create a slurry. The slurry is mixed about 10 minutes to achieve the preferred texture, elasticity and formability of the pulp product. As with any mixture of dry and wet components, variables in the components themselves may require adjustment of the formulation. For example, shredded newspaper may absorb more water than cotton fiber office paper so that the paper to water ratio may need to be adjusted. Once the mixture reaches the desired consistency, the resulting pulp is formed into desired shapes, molds, dimensional products and the like and cured over approximately 24 hours at approximately 90 degrees F. with high humidity of about 75%. It is also likely that the amount of water, paper, calcium aluminate and fly ash will need to be adjusted in differing climates and at different altitudes because the mixing process will be affected by those variables.
During the mixing process, the slurry can be further modified by adding in a variety of coloring agents, textures, paint, varnish, bleach, natural coloring agents, and highlighting materials such as glitter, gold leaf or similar products. The potential materials that can be added to the slurry to change the appearance and aesthetics of the finished product are almost endless. Moreover, the products can also be enhanced using known techniques, such as placing decorative items in a mold before adding the slurry to the mold, thereby creating decoration on incorporated only on the finished surface of the product after it is removed from the mold.
After mixing but before curing the slurry, it can be formed into a desired product by several methods. For example, picture frames can be made by placing the slurry into pre-formed molds prior to curing. Dimensional products can be made by molding or forming to slurry prior to or during curing. The structural integrity of the product is suitable to form one inch, two inch or larger dimensional products that can be cut and connected for use in applications similar to light weight wood. The end product will retain screws and other fasteners. In some instances, hangers or fasteners can be incorporated directly into the products during the curing period. The finished product can further be painted, colored, varnished or otherwise treated or decorated.
It will be understood that the present process is not limited strictly to use with recycled papers or paper fibers but may also be used to provide for extremely uniform pulp for paper making processes or for manufacturing articles from the pulp. This process can be modified to use virgin paper fibers and is not limited to recycled or raw paper. It will also be understood that the disclosed composition can be modified without departing from the spirit and scope of the invention. For example, modifications may have to be made to the process to accommodate differences in altitude and climate.
It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but include modified forms of those embodiments including portions of the embodiments in combinations of the elements and compositions so as to come within the scope of the following claims.
This application is a continuation-in-part of U.S. application Ser. No. 14/292,175 filed May 30, 2014 (non-provisional), which claims the benefit of priority to U.S. Application No. 61/830,482 filed Jun. 3, 2013 (provisional), the disclosures of which are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| 61830482 | Jun 2013 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14292175 | May 2014 | US |
| Child | 15068124 | US |
