PVC pallets and the like

• US 5,879,495 A
• Filed: 12/23/1997
• Issued: 03/09/1999
• Est. Priority Date: 12/23/1997
• Status: Expired due to Fees

• Current Assignee: Composite Pallet, LLC
• Original Assignee: Composite Pallet, LLC
• Inventors: Evans, Daniel W.
• Primary Examiner(s): SELLS, JAMES D
• Application Number:
  US08/997,576
• Time in Patent Office: 441 Days
• Field of Search: 156/82, 156/153, 156/272.2, 156/272.6, 156/281, 156/308.6, 156/244.11, 156/244.13, 156/250, 156/256, 427/223, 427/316, 427/322, 427/412.1
• US Class Current: 156/82
• CPC Class Codes: B29C 65/4815 Hot melt adhesives, e.g. thermoplastic adhesives
• CPC Class Codes: B29C 65/484 Moisture curing adhesives
• CPC Class Codes: B29C 66/02 Preparation of the material, in the area to be joined, prior to joining or welding B29C66/32 takes precedence
• CPC Class Codes: B29C 66/02245 Abrading, e.g. grinding, sanding, sandblasting or scraping
• CPC Class Codes: B29C 66/028 Non-mechanical surface pre-treatments, i.e. by flame treatment, electric discharge treatment, plasma treatment, wave energy or particle radiation B29C65/14 takes precedence; non-mechanical surface treatment of plastics in general B29C59/08 - B29C59/16
• CPC Class Codes: B29C 66/43421 with a right angle, e.g. for making L-shaped pieces
• CPC Class Codes: B29C 66/522 Joining tubular articles B29C66/53241 takes precedence
• CPC Class Codes: B29C 66/524 Joining profiled elements
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/7212 characterised by the composition of the fibres
• CPC Class Codes: B29C 66/72523 multi-channelled or multi-tubular B29C66/438, B29C66/5227 take precedence
• CPC Class Codes: B29C 66/73921 characterised by the materials of both parts being thermoplastics
• CPC Class Codes: B29K 2027/06 PVC, i.e. polyvinylchloride
• CPC Class Codes: B29K 2307/04 Carbon
• CPC Class Codes: B29K 2309/08 Glass
• CPC Class Codes: B29L 2031/7178 Pallets
• CPC Class Codes: B65D 19/0091 forming a continuous plane contact surface
• CPC Class Codes: B65D 19/18 made wholly or mainly of plastics material
• CPC Class Codes: B65D 2519/00034 Plastic
• CPC Class Codes: B65D 2519/00069 Plastic
• CPC Class Codes: B65D 2519/00079 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00104 : Plastic
• CPC Class Codes: B65D 2519/00114 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00149 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00184 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00218 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00253 : Combination, e.g. different elements made of different materials, laminates
• CPC Class Codes: B65D 2519/00273 : made of more than one piece
• CPC Class Codes: B65D 2519/00288 : made of one piece
• CPC Class Codes: B65D 2519/00293 : made of more than one piece
• CPC Class Codes: B65D 2519/00298 : skeleton type
• CPC Class Codes: B65D 2519/00318 : made of one piece
• CPC Class Codes: B65D 2519/00323 : made of more than one piece
• CPC Class Codes: B65D 2519/00333 : contact surface having a stringer-like shape
• CPC Class Codes: B65D 2519/00348 : contact surface of other form
• CPC Class Codes: B65D 2519/00373 : whereby at least one spacer is made of one piece
• CPC Class Codes: B65D 2519/00502 : whereby at least one side wall is made of two or more pieces
• CPC Class Codes: B65D 2519/00557 : without separate auxiliary elements
• CPC Class Codes: B65D 2519/00562 : chemical connection, e.g. glued, welded, sealed
• CPC Class Codes: B65D 2519/00631 : sidewalls not connected to each other, e.g. spaced apart frames
• CPC Class Codes: B65D 2519/00666 : Structures not intended to be disassembled
• CPC Class Codes: B65D 2519/00701 : Structures not intended to be disassembled
• CPC Class Codes: B65D 2519/00716 : non-removable lid or covers
• CPC Class Codes: Y10T 156/1062 : Prior to assembly

Abstract

A PVC pallet or crate is disclosed, wherein the pallet is made from PVC structural products such as hollow, extruded PVC profiles. The profiles are bonded together using an adhesive. The profiles are preferably surface treated before bonding to enhance the strength of the bond. The PVC structural products preferably incorporate an acrylic polymer impact modifier in a certain amount to greatly increase the toughness of the structural product. The adhesive is preferably a hot-melt moisture-cure polyurethane adhesive. The surface treatment is preferably achieved by plasma treating or flame treatment. A method for making PVC pallets or crates is also disclosed.

Claims

1. A method of making a PVC pallet or crate comprising the steps of:

a) providing a plurality of PVC support members;

b) pretreating the support members and cross members by performing one or more of the group consisting of flame treatment, corona discharge, solvent wiping, abrading, coating with a primer, plasma treatment and electrical etching;

c) arranging the support members in parallel, spaced relation, with a top surface on each support member facing substantially upward;

d) applying a bonding agent to each of said support members on the top surface thereof, said bonding agent selected from one or more of the group consisting of hot-melt moisture-cure polyurethane adhesives, polyester adhesives, epoxies, cyanoacrylate adhesives, polyurethane adhesives, ethyl methyl acrylate adhesives, ethyl vinyl acetate adhesives, hot-melt adhesives and thermoplastic elastomer adhesives;

e) providing at least one PVC cross member; and

f) transversely positioning said cross member on the top surface of said support members so as to sandwich said bonding agent therebetween.

2. The method of claim 1 wherein said method is carried out under an ambient temperature in the range of about 60°

F. to about 100°

F. and under ambient relative humidity of about 40% to about 85%.

3. The method of claim 1 wherein the surface temperature of the PVC support members and cross members is greater than 60°

F.

4. The method of claim 1 wherein the temperature of said bonding agent when applied is between 275°

F. and 375°

F.

5. The method of claim 1 including in step a) the steps of extruding said support members and cross members so that they are hollow with quadrangular cross-sections, and cutting the support members and cross members to length.

6. The method of claim 5 including in step a) the step of extruding one or more of the support members and cross members so as to provide them with at least one internal reinforcing rib.

7. The method of claim 1 wherein in step d) said bonding agent is applied in the form of a bead.