Abstract:
A planter having a body with a base and a depending sidewall is disclosed. The body has at least three layers, an outer layer, a central layer, and an inner layer. The outer layer is a polyurethane foam. The central layer is fiberglass. The inner layer is polyester resin. A method of making the planter is further disclosed.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 60/730,432, filed Oct. 26, 2005 entitled, HYBRID POLYURETHANE PLANTERS AND METHOD OF FORMING THEREOF. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to an improved planter (a.k.a. flower pot) and a method for forming the planter, and more particularly to a three-layered planter having an outer layer of polyurethane, a central fiberglass layer, and an inner resin layer. 
     2. Background Information 
     Planters are common objects typically used for holding plants and the like for decorative reasons or other purposes. However, planters are often characterized by heavy weights and a fragile structure, making them both difficult and potentially dangerous to move. Further, formations of planters are generally made in a static mold, increasing the possibility of uneven dispersion of strength support across the planter. 
     There is, therefore, a need for an improved method of forming a planter. 
     There is a further need for a method of forming a planter having an outer layer of polyurethane, a central fiberglass layer, and an inner resin layer. 
     There is a further need for a planter having an outer layer of polyurethane, a central fiberglass layer, and an inner resin layer. 
     SUMMARY OF THE INVENTION 
     The present invention seeks to improve upon the deficiencies of prior art planters by providing a polyurethane planter having an outer polyurethane layer, a central fiberglass layer, and an inner resin layer. The planter is, preferably, formed by a method having the following five steps: 1) rotational foaming; 2) bonding; 3) sheeting; 4) resin catalization; and 5) de-molding. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which: 
         FIG. 1  is an isometric view of a planter and the molds used by the disclosed method.  FIG. 1A  is a detailed view of the layers of a planter. 
         FIG. 2  is a flowchart of the disclosed method. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As shown in  FIG. 1 , a planter  10  is formed inside an aluminum cast mold  12  and a room temperature vulcanization (hereinafter “RTV”) mold  14 . The aluminum cast mold  12  is substantially rigid and does not typically deform during the method set forth below. The RTV mold  14  is substantially flexible and may be substantially deformed without damaging the RTV mold  14 . The RTV mold  14  can be made from material typically known in the art, for example, silicone. The RTV mold  14  has an inner surface  15 . The aluminum cast mold  12  is coupled to a centrifuge  16  or other like device. The type of centrifuge  16  utilized can vary within the spirit of the invention and can rotate and/or shake at various speeds. The planter  10  that results from this method has a body  11  corresponding to the shape of the aluminum cast mold  12  and the RTV mold  14 . Accordingly, the aluminum cast mold  12  and the RTV mold  14 , preferably, have a generally flat base  20  and an outwardly tapered sidewall  22 . The base  20  may include grooves (not shown) or channels that will allow water to drain from underneath the completed planter  10 . Thus, the planter body  11  also has a generally flat base  24  and an outwardly tapered sidewall  26 . As set forth below, the planter  10  has an outer layer of polyurethane foam  30 , a central layer of fiberglass  34 , and an inner layer of polyester resin  38 . The planter  10  is formed by performing the steps of rotational foaming  100 , bonding  110 , sheeting  120 , resin catalization  130 , and de-molding  140 . 
     Initially, for the step of rotational foaming  100 , the RTV mold  14  is placed  102  inside the aluminum cast mold  12 . Polyurethane foam  30 , or other like substance, is applied  104  to the RTV mold inner surface  15  while the centrifuge  16  is operational. The polyurethane foam  30  can be applied  104  either by hand or by automated means. The centrifuge  16  spins and/or shakes  106  throughout the addition of the polyurethane foam  30  and continues to spin  106  while the polyurethane foam  30  reacts and cures on the interior surface  15  of the RTV mold  14 . 
     Once the polyurethane foam  30  is cured, the bonding step  110  occurs. The bonding step  110  occurs when a wetting agent  32  is applied  112  to the inner surface of the polyurethane foam  30 . That is, the wetting agent  32  may be applied  112  onto the surface of the polyurethane by any means known in the art, such as spraying  114  or brushing  116 . It is not necessary for the wetting agent  32  to cover the entirety of the exposed polyurethane foam layer  30 , however, it is preferable. 
     Following the bonding step  110 , the sheeting step  120  occurs. The sheeting step  120  includes laying  122  fiberglass  34  on top of the polyurethane foam  30  and the wetting agent  32  such that there are preferably no areas left uncovered by fiberglass  34 . The fiberglass  34  is laid  122  onto the polyurethane foam  30  by any means known in the art, typically, by hand or machine. The fiberglass  34  is laid  122  in sheet  36  form within the RTV mold  14  so that the sheets  36  abut, that is, border or slightly overlap, each other. In an alternate embodiment, the bonding step  110  and sheeting step  120  may be combined/alternated. That is, the wetting agent  32  may be applied  112  to a segment of the polyurethane foam  30 , and fiberglass  34  is thereafter laid  124  on top of the wetting agent  32  on the same segment. The alternating process, that is, bonding  110  then sheeting  120 , is then repeated for any number of other segments on the polyurethane foam  30  until the polyurethane foam  30  is covered with both wetting agent  32  and fiberglass  34 . In another embodiment, the application  112  of a wetting agent  32  on one or a multiplicity of segments of the polyurethane foam  30  can occur substantially simultaneous with the laying  122  of the fiberglass  34 , provided that the fiberglass  34  is only added to segments of the polyurethane foam  30  that have already had the wetting agent  32  applied  112 . 
     Once the polyurethane foam  30  is covered by fiberglass  34 , the resin catalization step  130  occurs. That is, an unsaturated polyester resin  38  is coated  132  over the interior side of the fiberglass  34 , preferably by brushing. To ensure an even coating of polyester resin, the RTV mold  14  and aluminum cast mold  12  are rotated  134  during the resin coating  132  process. The rotation  134  of the RTV mold  14  and aluminum cast mold  12  may be accomplished either mechanically or by hand. The rotation  134  can occur during or between applications of the polyester resin  38 . The rotation  134  is preferably very slight, less than a full 360 degree turn of the RTV mold  14  and aluminum cast mold  12 . The polyester resin  38  is then cured  136 . Preferably, a second layer of unsaturated polyester resin  38 A is thereafter coated  138  on the cured first layer of polyester resin  38 . The rotation  134  of the RTV mold  14  and aluminum cast mold  12  may also occur during the second coating step  138 . The second layer of polyester resin  38 A is then cured  139 . 
     The process of forming the planter  10  is finalized in the de-molding step  140 . That is, the RTV mold  14 , with the planter  10  inside, is removed  142  from the aluminum cast mold  12 . The RTV mold  14  is removed  144  from the finished planter  10 . Preferably, the removal  144  of the RTV mold  14  is accomplished by peeling  146  the RTV mold  14  away from the planter  10  in a single piece. The RTV mold  14  may be used again to make another planter  10 . The planter  10  has an outer layer of polyurethane foam  30 , a central layer of fiberglass  34 , and an inner layer of polyester resin  38 . Such a planter  10  is evenly formed and is lighter and stronger than typical planters. 
     While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. For example, it will be appreciated that various sized, shaped or colored planters can be formed under the present invention with minimal adjustment. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention.