AU2001283515A1 - Strap for photograph album and scrapbook - Google Patents

Description

STRAP FOR PHOTOGRAPH ALBUM AND SCRAPBOOK

BACKGROUND OF THE INVENTIO 1. Field of the Invention

This invention relates to the preservation of photographs, and, more specifically, to reducing the presence, in photograph albums and scrapbooks, of chemical agents harmϊul to photographs.

2. Description of the Related Art

A very popular style of loose-leaf photograph album is manufactured and sold under the trademarks CREATIVE MEMORIES® and WEBWAY® by The Antioch Company of Yellow Springs, Ohio. This style of loose-leaf photograph album includes a pair of covers enfolding a plurality of pages. The covers and the pages are laced together by means of straps. The straps thread through hinge elements projecting from the leaves and through slots in the covers. The end portions of the straps are frictionally held by means of cover holders positioned on opposite sides between the outer leaves and the covers.

An early variant of this style of album is described in more detail in U.S. Patent No. 3,485,564 to Holes et al., issued on December 23, 1969, the disclosure of which is incorporated herein by reference. This style of album is also described in U.S. Patent No. 5,848,851 to Gunasekara, issued December 15, 1998, the disclosure of which also is incorporated herein by reference.

It has been recognized that chemical agents resident in materials used in constructing photograph albums and scrapbooks can damage the quality of photographs stored in these media over time. For example, low quality paper stocks often are pulped, bleached or refined in acid environments. For this reason, these low quality paper stocks produce paper with high acid contents. When the resulting paper is used in photograph album or scrapbook pages, the acids in the paper tend to discolor photographs mounted on those pages over time. For this reason, papers with low acid contents generally are preferred for use in photograph albums and scrapbooks. Chemical agents originating in other materials used in photograph albums or scrapbooks likewise are capable of discoloring photographs stored there. Consequently, there remains a need in the art for photograph albums and scrapbooks comprising only materials free from such chemical agents.

SUMMARY OF THE INVENTION This need and others are addressed by a kit for assembling a loose-leaf photograph album comprising one or more (most preferably two or three) flexible straps; a plurality of pages; and a pair of covers. Each page of the plurality of pages defines at least one projecting hinge element so dimensioned to receive the straps. Each cover of the pair of covers defines cover slots positioned and dimensioned to receive the flexible straps to bind the pair of covers to the plurality of pages.

Preferably, the flexible straps comprise a polymer substantially free of halogen. (The halogens, Group Vila on the periodic chart, include highly electronegative elements such as fluorine and chlorine.) Most preferably, the flexible straps comprise low density polyethylene.

In the past, such straps have been made from polyvinyl chloride ["PVC"], a polymer having a structural formula of the form:

As the structural formula indicates, PVC contains atoms of chlorine, a halogen. It has been discovered that the PVC used in such straps can break down over time to release hydrochloric acid (HC1). Without wishing to be bound by any theory of operation, it is believed that the effects of heat, ultraviolet radiation, mechanical stress and air pollution can all contribute to the breakdown of the PVC. In addition, the acid released in the process of breaking down the PVC can contribute to the further breakdown of the PVC, thereby tending to accelerate the process. Additives such as plasticizers and stabilizers have been used to improve the physical properties of PVC polymer materials. For example, stabilizers such as metal salts have been added to neutralize the agents released in the process of breaking down PVC so as to reduce the effect of those agents in accelerating the process. Similarly, low molecular weight plasticizers such as phthalates have been added to increase the flexibility of the polymer material, since unplasticized PVC resin tends to be too rigid for use in straps for photograph albums or scrapbooks. Commonly, such stabilizers and plasticizers do not bond with the polymer chains; under appropriate circumstances, they can move relative to the polymer chains which define the structure the straps. Both the hydrochloric acid released by the breakdown of the PVC, and the stabilizers, plasticizers and other additives used in the PVC materials, pose threats to the preservation of photographs stored in such photograph albums or scrapbooks. Under appropriate conditions, these agents are capable of leaving the straps and interacting with the photographs, thereby potentially discoloring those photographs.

The straps of photograph albums or scrapbooks formed in accordance with the present invention comprise polymer materials substantially free of halogen. Many such polymer materials, especially those comprising polyethylene, are highly stable under ordinary environmental conditions. Even if these polymers were to break down, however, they contain no halogen atoms in their structural formulae. Consequently, the strong conjugate acids of such halogen atoms do not form if the polymer breaks down.

Alternatively, the flexible straps of photograph albums or scrapbooks formed in accordance with the invention may comprise polyurethane, which likewise is fairly stable and does not include halogen atoms in its structural formula.

Therefore, it is one object of the invention to provide flexible straps for photograph albums formed from chemically stable polymers substantially free of chemical agents capable of promoting the discoloration of photographs. These and other objects, features and advantages of the present invention will be described in further detail in connection with preferred embodiments of the invention shown in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the parts of a photograph album or scrapbook in accordance with the present invention, with a portion of one cover broken away to show details of the binding; Fig. 2 is a top plan view of a strap for the photograph album of Fig. 1 , the bottom plan view being a mirror image thereof; and

Fig. 3 is a side elevational view of the strap of Fig. 2, the opposite side elevational view being a mirror image thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

As best shown in Fig. 1, a preferred loose-leaf photograph album or scrapbook 10 includes a pair of laminated padded covers 12 and 14 enfolding a plurality of pages 16. The covers 12, 14 and the pages 16 are laced together by means of straps 18 and 20. The straps 18, 20 are received through sets of aligned hinge elements (collectively 22 and 24), preferably in the form of stitches, which project from the pages 16; and through cover slots 26 (only one shown) in the covers 12, 14. The cover slots 26 on each of the covers 12, 14 bear substantially the same spacial relationship to each other that each hinge element 22 bears to the other hinge element 24 projecting from the same page 16, thereby facilitating the lacing of the straps 18, 20 through the hinge elements 22, 24 and the cover slots 26. The straps 18, 20 preferably also pass through slots 30 and 32 (only two shown in Fig. 1) in cover holders 34 and 36 positioned immediately inside the covers 12, 14. The straps 18, 20 and the hinge elements 22, 24 preferably are covered by a removable spine (not shown) having ends which fit into pockets 38 (only one shown) defining recesses in the covers 12, 14.

In the embodiment shown in Fig. 1, the straps 18, 20 frictionally engage the cover holders 34, 36 so as to bind the covers 12, 14 and the pages 16 into a photograph album or scrapbook 10. The spine (not shown), the straps 18, 20 and the cover holders 34, 36 are removable to permit additional pages (not shown) to be laced into the album 10.

As best shown in Fig. 2, a preferred strap 18 in accordance with the invention consists of a polymeric band or strip having a length dimension 50 and a width dimension 52. The strap 18 is prismatic along most of its length, defining a rectangular cross-section. End portions 54 and 56 of the strap 18 each taper linearly from their maximum width toward rounded or arcuate ends 58. Most preferably, an upper surface 60 of the preferred strap 18 is roughened to increase friction between the strap 18 and the cover holders 34, 36.

As best shown in Fig. 3, the preferred strap 18 also has a height dimension 70 which is small compared to the length dimension 50 and the width dimension 52 (Fig. 2). Most preferably, the height and width dimensions 52 (Fig. 2), 70 are selected so that the strap 18 fits easily through the hinge elements 22, 24 and the cover slots 26 but frictionally engages the cover holders 34, 36. Although the configuration of the preferred strap has been described in detail, the configuration is not critical to the present invention.

The preferred strap 18 is formed by molding a translucent low density polyethylene polymer material. The preferred low density polyethylene resin for use in the strap of the present invention is Polyethylene 9931 Low Density resin, available from Dow Chemical Company of Midland, Michigan. Although this resin produces straps having just enough flexibility to be roughly serviceable in photograph album or scrapbook binding, it is desirable to add an elastomer such as ENGAGE Polyolefin Elastomer (an ethylene alpha-olefin copolymer), available from DuPont Dow Elastomers L.L.C. of Wilmington, Delaware, to increase the flexibility of the strap at room temperature. An especially preferred strap is molded from a copolymer resin comprising approximately 80 wt% Polyethylene 9931 Low Density resin and 20 wt% ENGAGE Polyolefin Elastomer. Neither Polyethylene 9931 Low Density resin nor ENGAGE

Polyolefin Elastomer are believed to contain substantial amounts of halogens or halogenated compounds. The stability of the preferred polymeric material, and the absence of halogen and halogenated compounds from the material, reduces the likelihood that the preferred polymeric material will break down to release acids capable of discoloring photographs stored in the photograph album or scrapbook 10. Various changes or modifications in the invention described may occur to those skilled in the art without departing from the true spirit or scope of the invention. The above description of preferred embodiments of the invention is intended to be illustrative and not limiting, and it is not intended that the invention be restricted thereto but that it be limited only by the true spirit and scope of the appended claims.

We claim:

Claims (9)

-CLAIMS-

1. A kit for assembling a loose-leaf photograph album comprising: a plurality of flexible straps; a plurality of pages, each page of said plurality of pages defining a plurality of hinge elements so dimensioned to receive said plurality of flexible straps; and a pair of covers defining cover slots positioned and dimensioned to receive the plurality of flexible straps to bind the pair of covers to the plurality of pages; said plurality of flexible straps comprising a polymer substantially free of halogen.

2. The kit as recited in claim 1 wherein said plurality of flexible straps each comprise polyethylene.

3. The kit as recited in claim 1 wherein said plurality of flexible straps each comprise low density polyethylene.

4. The kit as recited in claim 1 wherein said plurality of flexible straps each comprise polyurethane.

5. The kit as recited in claim 1 including a pair of cover holders for placement between said plurality of pages and said pair of covers for frictional engagement with said plurality of flexible straps.

6. A kit for assembling a loose-leaf photographic album comprising: a plurality of flexible straps; a plurality of pages, each page of said plurality of pages defining a plurality of hinge elements so dimensioned to receive said plurality of flexible straps; a pair of covers defining cover slots suitably dimensioned to receive one of said plurality of flexible straps, the cover slots bearing substantially the same spacial relationship to each other that the plurality of hinge elements defined on a page of the plurality of pages bear to one another; a pair of cover holders for placement between said plurality of pages and said pair of covers for frictional engagement with said plurality of flexible straps; said plurality of flexible straps comprising a polymer material substantially free of halogen.

7. The kit as recited in claim 6 wherein said plurality of flexible straps each comprise polyethylene.

8. The kit as recited in claim 6 wherein said plurality of flexible straps each comprise low density polyethylene.

9. The kit as recited in claim 6 wherein said plurality of flexible straps each comprise polyurethane.