Systems for Attaching Wood Products

Abstract

The present invention is a system of building materials with surface regions destined for joint formation that are treated with an adhesive partially comprised of a mixture of epoxy resin (96.0-99.9 parts) and hardener (4.0-0.1 parts), such that the epoxy resin / hardener mixture constitutes 50-100% of the adhesive. In an alternative embodiment, the adhesive may have epoxy resin (96.0-99.9 parts) such that the epoxy resin constitutes 45-95% of the adhesive. The remainder of the adhesive may be one or more of the following: hardeners, plasticizing agents, diluents, thickeners, fillers, colorants, opacifying agents, preservatives, and surfactants.

Description

FIELD OF THE INVENTION[0001]This invention relates generally to wood products which may be attached via an adhesive which is applied at a manufacturing stage such as, for example, a factory, prior to a construction phase, i.e., when the wood products are assembled together to form structural components.BACKGROUND OF THE INVENTION[0002]It is common practice in North America for buildings and / or residential structures to be comprised of discrete structural building materials, which include framing members and sheet goods. The building materials are typically connected in these structures by use of common mechanical fasteners, such as nails, screws, and staples. Other mechanical fasteners that are used include plates, anchors, hangers, bolts, split rings and clips. Adhesives are also commonly used in combination with mechanical fasteners to help connect certain types of building materials. For example, liquid construction adhesives are commonly utilized in joist-to-subfloor panel conne...

AI Technical Summary

Benefits of technology

The patent text discusses the use of special adhesives that can be applied to building materials in a manufacturing environment and stored for some time before being assembled at a construction site. These adhesives are designed to be applied to building materials quickly and easily, and can tolerate long open-assembly-times. The technical effect of this invention is to provide stronger and more durable connections between building materials that are easy to assemble and have improved strength and durability.

Problems solved by technology

In spite of the advantages associated with construction adhesives, their usage is somewhat limited, due in part to the difficulty and time required to apply them to building materials during the construction process.

This device is relatively slow and labor intensive.

In cold or freezing weather, there is a tendency for the viscosity of liquid construction adhesives to increase, which makes them even more difficult to apply.

Thus, some builders choose not to use construction adhesives because of the time and difficulty associated with their use.

When this occurs, the contribution of the adhesive to the strength of the joint will be diminished, and in many cases it will obstruct the fit of the joint.

Another failure mode associated with conventional construction adhesives relates to their use on building materials that are wet from exposure to rain or snow.

We have found that most commercially available construction adhesives yield weaker joints when they are applied to wet building materials.

Yet another failure mode relates to incomplete or non-uniform adhesive application rates.

In this situation, at least some portion of the joint surface receives an insufficient amount of adhesive.

Thus, PSAs applied to building products can generally remain sticky and receptive to bond formation for very long periods of time.

Unfortunately, these PSAs also exhibit non-reversible deformation when subjected to high stress loads (greater than about 1 psi) for prolonged periods of time.

This last attribute makes PSAs unsuitable for applications involving large, sustained loads, such as those experienced by adhesives at the joist-to-subfloor panel connection.