GB2173449A - Binding method and booklet - Google Patents

Abstract

A method of binding sheets together to form a booklet comprising the steps of stacking the sheets offsetting the inside edge of each sheet with respect to the adjacent sheet with the first sheet at the bottom to expose a narrow portion of the rear surface of each sheet and the edge, applying a length of binding tape having a coating of pressure sensitive adhesive on one surface along the offset edges of the sheets with the adhesive contacting said narrow portion of the rear surface of each sheet and a portion of the edge, placing a cover beneath the edges of the sheets, said cover having a front cover portion and a rear portion joined together along a fold line, aligning the inside surface of the front cover portion of said cover along the edge of the first sheet with the edge of the first sheet spaced from and parallel to the fold line, and pressing a marginal edge of the binding tape, adjacent to and extending parallel to the edge of the first sheet, to the inside surface of said front cover portion between said edge of the first sheet and the fold line. There is claimed independently a cover having in the binding area a surface such that the binding tape is adhered to it within a defined range of peel strengths.

Description

SPECIFICATION Binding method and booklet Technical Field This invention relates to an improved method of binding sheets in a novel cover to form a booklet, and in one aspect to an improved cover construction for use in forming the booklet.

Background Art The present invention relates to an improved method of forming a booklet by the use of a pressure-sensitive adhesive tape to bind the sheets together and in a cover or binder.

Adhesives have been used to bind sheets in the spines of covers or to bind signatures in the spines of covers or other backings. Also, adhesives have been placed in covers to bind the front or back sheet of a booklet or pamphlet into a cover. The latter adhesives being strips of tape which are applied to the cover and are positioned to be applied against the cover sheet and back sheet of a bound document.

In the first type of binding, hot melt adhesives are used or pressure sensitive adhesives are used and the adhesive is applied against the edge of the sheet. Upon the adhesive bond being made the sheets are bound. When such a book or booklet so formed is placed on a shelf or in a file the pages apply a peeling force against the adhesive and with time and where there is any weight applid, the bond may break. Where tape-like sheets are used to hold a bound document in a cover, such as disclosed in United States Letters Patent Nos. 3,749,422; 3,749,423; 3,825,963 and 3,834,739, the bound document is adhered to the front and back covers to aid in retaining the document in the cover. The adhesive used to hold the document is subjected to a shear force at the top and bottom of the covers or the cover page and rear sheet are subject to wrinkling.These patents are thus not believed to be teachings of the present invention or of binding pags together and to a cover by a single strip of tape. That strip being a strip of flexible pressure sensitive adhesive coated tape.

The present invention provides a method of binding sheets together and in a binder in such a way that the sheets do not tend to peel from the tape when the bound booklet is stacked, placed on a shelf or suspended in a file.

The types of covers used for containing the sheets to form the booklet are covers preferably of paper and have a reinforcing protective coating or film strip at the crease or fold line or polymeric covers of a material to permit the tape to be applied and yet permit controlled adhesion of the binding tape to the cover. The preferred adhesion is measurable between 200 and 700 grams per 1.27 cm of width of the binding tape.

A cover which is formed only of paper is not always suitable. Sometimes it is necessary or desirable to remove the bound pages from the cover. This results because of misalignment of the pages with respect to the cover when binding the same, or, it may be desirable to make changes in the bound pages and it is prudent and economical to save the covers for reuse if possible. When the cover stock is paper, the pressure-sensitive adhesive on the binding tape will adhere to the paper stock. Attempts to remove the tape will cause the paper stock to delaminate or tear before the tape adhesive is released or peeled from the cover.

The present invention is directed at a method of binding sheets together and in a cover formed of cover stock which cover stock may be paper or a polymeric material designed to provide an attractive cover to which a binding tape will adhere adequately, and when bound, the adhesive holding the pages and holdig the bound pages in the cover is positioned to avoid a peeling force being applied to the adhesive.

The present invention has as one object the provision of a binding cover which is adapted for use with a tape binding system for binding sheets together and securing the sheets in the cover.

The cover of the present invention is so designed that the tape will hold the bound pages in the cover and will restrict displacement under normal use and storage conditions.

Disclosure of Invention The present invention is directed to a binding cover for use in binding sheets together and to the method of binding sheets in the cover to form a novel booklet. The cover is formed such that it will securely retain the bound sheets in place under normal handling and storing conditions without the sheets peeling from the binding tape or the tape peeling from the sheets or the cover.

The binding cover of the present invention comprises a sheet of cover stock, generally folded along a central line as at a score line or mere fold line. A guideline is placed on the inside surface of the front or cover portion of the sheet for indicating the position of a marginal edge of the bound sheets.If the sheet comprises a paper cover stock as opposed to a polymeric cover stock it is preferred that a protective coating be applied along the fold line which will have sufficient adhesion to the binding tape to secure the pages and yet afford a release of the binding tape without a delamination of the cover, breaking of the tape or adhesive transfer to the coated area upon peeling the binding tape from the cover. the desired range for this adhesion and release limitation is: the adhesion to the binding tape must be measurable between 200 and 700 grams per 1.27 cm (ASTM D 3330-81) for pressure-sensitive tape identified as "Scotch" brand binding tape No. C-7888, available from Minnesota Mining and Manufacturing Company of St. Paul, Minnesota.

The cover is formed with a front portion and a back portion. The protective coating extends on each side of the fold line and onto the inside of the cover portion by at least about 3.2 mm to 19 mm. The guideline is printed on the inside of the front cover portion about 0.8 to 3.2 mm from the score or fold line to indicate the position of the inside edge of the first sheet of the bound sheets when placing- them in the cover. The remaining sheets are shingled in relationship to the first sheet and to each other in a direction away from the from the score line and over the front cover portion. Thus when the sheets are so bound in the cover, the portion of the strip of tape adhering the sheets to the cover is positioned between the guideline and the fold line.Thus, when the booklet is stacked, or the cover portions are closed to lay the sheets flat the binding tape remains flat against the inside of the front cover portion. It does not tend to peel from the cover or to have the sheets tend to peel away from the tape as the- sheets lay flat against each other.

The booklet is assembled by placing the sheets to be bound on one another with the edge of each sheet which is to be placed against the back of the booklet shingled or offset from the adjacent edges of adjacent sheets uniformly. A strip of a pressure sensitive adhesive tape is placed along the shingled edges and the adhesive coated surface thereof is pressed against the shingled edges to contact a rear surface portion and edge portion of each sheet. The sheets are stacked with the first sheet of the booklet on the bottom of the sheets. The inside edge of this first sheet is aligned along the guideline on the inside of the opened cover placed beneath the sheets. The marginal edge of the binding tape is then pressed against the cover between the guideline and the score or fold line. The booklet may then be closed and turned over.Opening the first portion will expose the first sheet and successive sheets. The sheets are held by the adhesive contacting a portion of the back surface of each sheet and the adjacent inside edge.

Brief Description of Drawing The present invention will be described in greater detail with reference to the accompanying drawing wherein: Figure 1 is a perspective view of an opened cover constructed according to the present invention; Figure 2 is an enlarged fragmentary transverse sectional view of the cover of Fig. 1 showing the sheets in place, the sheets aligned on the cover and the tape applied to the sheets and cover; Figure 3 is an enlarged diagrammatic detail view showing the booklet of the present invention formed according to Fig. 2; and Figure 4 is an enlarged diagrammatic detail view showing a booklet constructed where the inner edge of the first sheet of the booklet is aligned with the fold line or is positioned on the inside surface of the back portion of the - cover.

Detailed Description The present invention provides an improved binding cover for use in making a booklet or brochure for purposes of presentation of a professional looking document, report, or other bound work.

The cover 5 of the present invention is formed of cover stock and comprises a sheet 6, having dimensions for the U.S.A. market of preferably about 46.5 cm by 28.9 cm, with a score line or fold line 7 disposed generally centrally and joining the long edges thereof. The sheet 6 can be of paper cover stock with a starch sizing and may have an embossed finish. The sheet 6 has a binding area on which a protective coating 8 is applied. The binding areas is on the inner surface of the front cover portion between a guideline 9, printed on the inside of the front cover portion 10 of sheet 6, and the score or fold line 7. The position of the guideline 9 is highlighted by a series of arrows 12 printed on the sheet.

This coated area 8 of the cover provides a prepared cover which will have the desired release characteristic for a pressure-sensitive adhesive binding tape sufficient such that bound shets are secured in the covers sufficiently to prevent the sheets from coming loose from the covers during ordinary use or storage in a file and the sheets can be removed from the cover without breaking the binding tape, delaminating the cover stock or transferring of the adhesive. Both the ease of removal of the tape from the cover and the secure binding of the sheets for storage are critical factors to the present invention. The protective coating and the desired range for this adhesion is preferably measurable between 200 and 700 grams per 1.27 cm (ASTM D 330-81) for pressure-sensitive adhesive tape identified as "Scotch" brand binding system tape No.C 7888 available from Minnesota Mining and Manufacturing Company of St. Paul, Minnesota.

The binding system tape comprises a backing of a unified nonwoven fibrous fabric carrying a continuous coating of a pure rubbery copolymer pressure-sensitive adhesive. The backing is very supple and the adhesive is applied to the backing and is 0.076 mm thick. The backing will have a barrier coating to restrict migration of the adhesive through the porous backing. The binding tape had a 1800 peel adhesion (ASTM D 3330-81) of 350 grams per 1.27 cm of tape width.

The binding tape suitable for the practice of the present invention is described in United States Letters Patent No. 4,558,888 issued December 17, 1985, the disclosure of which is incorporated herein by reference.

Examples of the protective coating 8 include an acrylic low adhesion backsize (L.A.B.) material formulated according to United States Letters Patent No. 2,607,711, an L.A.B. of urethane formulated according to United States Letters Patent No. 2,532,011 or a silicone L.A.B. such as sold under the trademark "Syl-Off" with the designation 294 from Dow Chemical Company of Midland, Michigan. Other protective coatings 8 include a strip of polyester film placed in an embossed area of sheet 6 as illustrated in the drawing. The film can be 0.025 mm film or 0.06 mm polypropylene film such as available from Toray, Inc. of Tokyo, Japan. A polystyrene or polyvinyl chloride could also be used. The films are discussed in the earlier application.

The protective coatings 8 applied in the central area of the cover which will achieve the adhesion desired are formed according to the following Examples.

EXAMPLE 1 "Jersey" 80 pound embossed leatherette finish paper cover stock from James River Corporation, Riegel Division, Milford, New Jersey 08848 was coated with an acrylic low adhesion backsize (L.B.A.) material formulated according to U.S.A. Patent No. 2,607,711. The cover stock was coated with 5% acrylic low adhesion backsize material using a 0.001 inch (0.025 mm) coating thickness with a hand coater. The sample was then air dried and tested by applying a hair inch wide (1.27 cm) piece of "Scotch" brand binding tape No. C-7888 to the coated area and following the test procedures of ASTM D 3330-81, but applying the binding tape directly to the coated area. The initial adhesion strength was 210 grams per 1.27 cm of tape with an accelerated aging over 14 days at 210 degrees F. (about 50"C) of 320 grams.

Similar tests were made using a urethane L.A.B. formulated according to U.S.A. Patent No.

2,532,011 and a silicone L.A.B. but the percentage of solids had to be reduced significantly.

When the paper stock was coated with urethane L.A.B. with 1% urethane solids to a wet thickness of 0.001 inch (0.025 mm) and the silicone L.A.B. was coated with 0.5% silicone solids to a wet thickness of 0.001 inch (0.025 mm), the initial adhesion strength with the urethane L.A.B. was 240 grams per 1.27 cm of tape width. The silicone L.A.B. had an initial adhesion strength of 200 grams per 1.27 cm of tape width. The silicone L.A.B. was "Syl-Off" 294 from Dow Chemical Company, Midland, Michigan.

EXAMPLE 2 "Jersey" 80 pound embossed leatherette finish paper cover stock from James River Corporation had a strip of 2 mil (0.05 mm) thick polyester film (Minnesota Mining and Manufacturing Company, 3M OR 870197) applied along the fold line of the cover. The film was coated with an acrylic low adhesion backsize with 5% acrylate solids using a 0.01 inch (0.025 mm) orifice hand coater. The strip of polyester film was air dried and then tested with the half-inch "Scotch" brand binding tape No. C-7888. The initial peel adhesion strength was 165 grams of 1.27 cm width of tape, with an accelerated aging strength of 245 grams per 1.27 cm of tape width.

The use of the acrylic L.A.B. coating at 5% solids on the polyester failed to produce a useful protective coating for the paper cover stock. It would not be appropriate to have a cover for binding sheets if the sheets could fall from the cover under normal usage within minutes or days of the sheets being bound.

EXAMPLE 3 A Minnesota Mining and Manufacturing Company 0.001 inch (0.025 mm) polyester film designated as No. 860140 was applied to the James River, Jersey 80 pound embossed paper cover stock and tested with the "Scotch" brand binding tape No. C-7888. The initial peel adhesion strength of the binding was 400 grams and the strength after accelerated aging, as described above in Example 1, exceeded 1,040 grams, per 1.27 cm of tape width.

Polyester film which is uncoated and adhered in a cover may make a suitable binder but it lacks the reusable characteristic over a period of time. The initial binding strength is such that the cover would be reusable to adjust the position of the bound sheets in the cover but would not be a reusable cover after a period of time when the documents bound in the cover were to be removed.

EXAMPLE 4 A 0.06 mm thick polypropylene film, available from Toray, Inc. of Tokyo, Japan, was supported on a surface for the adhesion peel test. There was no treatment given or coating applied to the exposed surface of the film. The initial adhesion strength was 320 grams per 1.27 cm width of Scotch brand binding tape. Test results after accelerated aging were 440 grams.

Polypropylene as available from Toray, Inc. proved very suitable as a protective coating for the cover stock, and permitted the applying and removal of the binding tape without transfer of the adhesive from the binding tape to the film, without deleteriously effecting the paper stock of the cover, or breaking of the binding tape.

EXAMPLE 5 A 0.003 cm thick polypropylene film made by Minnesota Mining and Manufacturing Company was bound in the cover. The film was passed under a corona bar. the peel adhesion test showed an initial adhesion strength of 450 grams on one test, 430 grams on the second. The age test of 14 days at about 50"C, to simulate one year, provided a peel adhesion strength of 560 grams and 590 grams per 1.27 cm of tape width in two aging tests.

This polypropylene film also provided a satisfactory protective coating.

Another untreated film which suitably passed the test was cellophane purchased from E.I. du Pont de Nemours & Co., of Wilmington, Delaware, which was 0.0014 inch (0.036 mm) thick.

This material had an initial adhesion strength of 330 grams per 1.27 cm of tape width and an accelerated aging adhesion of 570 grams.

Untreated polystyrene film purchased from Dow Chemical Company had an initial peel adhesion strength of 420 grams, and an accelerated aging strength of 530 grams per 1.27 cm of tape width.

Films of untreated polyvinyl chloride had an initial peel adhesion strength of 400 grams per 1.27 cm of tape width but the tape stuck to the surface and could not be removed after accelerated aging.

An untreated cellulose acetate film had an initial adhesion strength of 440 grams per 1.27 cm of tape width and an accelerated aging adhesion strength of 960 grams.

Unplasticized polyvinyl chloride film had an initial peel adhesion strength of 320 grams per 1.27 cm tape width, but, after accelerated aging, stuck to the surface of the film and could not be removed.

The films can be adhered to the inside of the covers by a pressure-sensitive adhesive transfer tape such as Scotch brand No. 465 adhesive transfer tape available from Minnesota Mining and Manufacturing Company of St. Paul, Minnesota.

A cover which is suitable for use in tape binding sheets must have a peel adhesion strength of about 200 grams per 1.27 cm of binding tape width and not exceed about 700 grams per 1.27 cm of binding tape width. In this range, the bound sheets can be removed from the document without breaking the binding tape, and the sheets are secure enough in the covers to prevent the sheets, at least 25 bound pages of 20 pound bond paper per 1300 square feet ream size, from coming loose from the covers during storage in a file. Both the ease of removal and the secure binding of the sheets for storage are factors of commercial importance for the covers.

It is important that a protective coating be applied to a paper cover stock binder to prevent the paper stock from delaminating when removing the binding tape from the cover.

The paper surface treatment or special film applied to the paper must conform to the paper surface and the score lines. It must not substantially alter the opening or closing characteristic of the cover during binding of the sheets or in normal handling or filing. A coating causing embrittlement results in reduced flexibility of the cover stock during binding and subsequent handling and filing. The use of films or coating over 0.076 mm in caliper for other protective coating tend to reduce the flexibility and conformity of the covers for binding and subsequent handling for filing.

The use of polymeric films or a coating treatment in excess of 0.076 mm in caliper on the inner surfaces of the front and rear cover adjacent the fold line adds substantially to the thickness of the bound document and thus reduces its commercial suitability. The area within the cover that is treated is dependent on the width of the binding tape used, the number of pages being bound in the cover and the binding of multi-stacks of papers in one cover.

The method of forming a booklet according to the present invention comprises arranging sheets 15 to be bound in the proper order with the sheets on one another. The sheets 15 may be placed in a stack with the first sheet on the bottom. The sheets are then offset from each other such that the edges of the sheets which are to be bound against the spine of the booklet are shingled or offset substantially uniformly from the first sheet. The shingling can be accomplished by an apparatus, e.g., an apparatus for binding sheets such as disclosed in United States Letters Patent No. 4,581,296 assigned to the assignee of this application, the disclosure of which is incorporated herein by reference. In that patent, the sheets are aligned along the inside edge of each sheet. The stack of sheets are then clamped together at their opposite edges.The inside edges are then moved through an arc and brought over the clamped edges to rest on a platen. The bending of the sheets in the arc places the inside edges in a shingled or offset condition exposing preferably a portion of the rear surface of each sheet and the edge.

With the inside edges of the sheets 15 shingled a strip 16 of binding tape is placed along the length of the edges. The adhesive coated surface of the binding tape is pressed into contact with a portion of each surface and the edge of each sheet. A marginal edge of the tape extends beyond the edge of the bottom sheet. A cover 5 is placed beneath the sheets. The guideline 9 of the cover is aligned with the edge of the lower sheet of sheets 15. The adhesive coated marginal edge of the binding tape 16 is then pressed against the inside surface of the front cover portion of the cover between the guideline 9 and the fold line 7 and if the width of the binding tape is such, the remainder of the marginal edge is adhered to the cover across the fold line 7 and onto the inside of the rear portion of the cover as illustrated in Figs. 2 and 3 of the drawing.The guideline 9 as illustrated is printed on the inside surface of the front cover portion about 0.8 to 3.2 mm from the fold line 7 or it can be printed on the film 8 forming the protective coating and the film is laminated in registration to properly position the printed guideline on the front cover portion of the sheet 6.

This method of binding the sheets 15 and binding the sheets to a cover provides a booklet which can withstand normal use and storage, as in a stack on a shelf as with books on edge in a shelf, or in a file and the sheets do not peel away from the binding tape or the tape does not peel away from the protective coating of the cover. As shown in Fig. 4, if the first page is bound in the booklet with the inside edge of the front sheet 20 bound in the cover 21 and aligned at the fold line 24 or parallel to the fold line and on the inside of the rear cover portion 22 of the cover 21, closing the cover about the fold line 24 causes the binding tape 25 to be peeled from the surface of the back cover portion. The amount of peel depends on the number and thickness of the sheets but the closing causes a peel force.Also when the booklets constructed as shown in Fig. 4 are stacked, the inside edge of the front sheet peels from the adhesive on the tape 25. Subsequent opening of the booklet finds the first sheet loose or partially free of the adhesive bond. In Fig. 4, if the tape was held very tightly to the inside of the back cover, the inside edges of the paper would be curled or bent. The stiffness of the paper and storage conditions create a peeling force over a period of time causing a release of the inside edge of the first sheet 20 from the tape. With thick booklets, additional sheets will become loosened.

The booklet illustrated in Fig. 3, formed according to the present invention does riot have a bend, bow or peeling force in either the tape 16 or the sheets 15. The adhesive coating on the tape 16 is subjected to shear forces when the booklet is placed on a shelf or is inverted in a file with the fold line of the cover of the booklet upward. In a stack the sheets are flat. The tape 16 is flat between the first sheet 15 and the fold line 7 of the cover 5. The adhesive of the tape 16 may be in compression. In any event there are no peel forces applied.

The shear strength of the binding tape 16 in relationship to its peel adhesion strength on the protective coating is much larger. The following chart shows the difference between shear strength on different protective coating materials verses peel adhesion using a binding tape 16 as described in Letters Patent No. 4,558,888 referred to hereinabove and sold by Minnesota Mining and Manufacturing Company of St. Paul, Minnesota as Binding Tape No. C-7888. The test was conducted by hanging a 200 gram weight to a piece of tape having an area 0.5 inch by 0.5 inch adhered to the coating material and recording the time for complete separation of the tape from the material.

Material Peel (in minutes) Shear (in minutes) Polypropylene 5 samples 2.86 (average) 935.8 (average) Polyester 5 samples 6.9 (average) 1764.7 (average) Paper, "Jersey" 19.16 (average) 1600.2 (average) Cover stock surface 5 samples Paper ("Jersey" 3.0 (average) 1233.3 (average) Cover stock) with a wet coating thickness of 0.001 inch, 1% acrylic low adhesion backsize material 3 samples Polyethylene 0.1 (average) 237.3 (average) 5 samples Unplasticized 143.96 (average) 608.7 (average) polyvinyl chloride 5 samples "Jersey" is a tradename of James River Corporation, Milford, New Jersey 08848.

In conducting the test above, Procedure A of the ASTM D-3654-82 test standard was used except the panel was surfaced with the material being tested. In conducting the peel test above the ASTMD-3330-83 was followed for preparation of the specimen and it was peeled to the point where the area adhered remained at 1 27 by 1.27 cm. The peeling was conducted with the specimen as in ASTMD-3654-82 using a 200 gram weight. The times were recorded for complete separation of the tape from the test surface.

In an alternative embodiment the front cover 15 or front face of the binding 5 could be formed of a transparent film which is laminated to a paper cover stock. The transparent cover avoids the need for a title or label to be applied to the outside face of the cover as the title page of the bound document can be seen readily through the transparent cover portion of the binder.

The binder 5 may be formed of a polymeric film and not require a protective coating if the binder is formed of a polymeric material having an adhesive strength with respect to the binding tape of between 200 and 700 grams per 1.27 cm of binding tape width under a standard 1800C peel adhesion test for pressure-sensitive adhesive tapes. An example of a suitable film of polymeric material is polypropylene with the sheet formed with a score line 7 allowing the cover to close and open to a flat position.

Claims (18)

1. A cover for covering and supporting sheets of bound paper in a booklet or brochure comprising a sheet of cover stock of predetermined size for covering the bound sheets when folded along a fold line, and said sheet having a surface adjacent the line for protecting said cover stock and having sufficient adhesion to a pressure-sensitive adhesive binding tape to hold bound sheets to said cover and afford release of said binding tape under peeling forces between 200 and 700 grams per 1.27 cm width of said pressure-sensitive adhesive binding tape without deleterious effect to the cover stock or to the binding tape.

2. A cover according to claim 1 wherein said surface is defined by a protective coating applied to the cover stock on both sides of the fold line.

3. A cover according to claim 1 wherein said surface is defined by a protective coating of a low adhesion backsize coating applied to a cover stock of paper and said coating has an adhesion force on the binding tape of between 200 and 700 grams per 1.27 cm of binding tape width under a standard peel adhesion test of pressure-sensitive adhesive tape.

4. A cover according to claim 1 wherein said cover stock is paper and said surface is defined by a protective coating comprising a length of polymeric film applied along the fold line and having an adhesion force on the binding tape of between 200 and 700 grams per 1.27 cm of binding tape width under a standard peel adhesion test for pressure-sensitive tape.

5. A cover according to claim 4 wherein said film is one of polypropylene, polystyrene, and cellophane.

6. A cover according to claim 3 wherein said low adhesion backsize contains 5% acrylate solids in a wet coating thickness of 0.025 mm.

7. A cover according to claim 3 wherein said low adhesion backsize contains 1% urethane solids in a wet coating thickness o 0.025 mm.

8. A cover according to claim 3 wherein said low adhesion backsize contains 0.5% silicone solids in a wet coating thickness of 0.025 mm.

9. A cover according to any preceding claim wherein a guideline is formed on the inside surface of the cover parallel to said line for indicating the position of a marginal edge of said bound sheets.

10. A cover according to claim 9 wherein said guideline is placed 0.8 to 3.2 mm from said line to receive the marginal edge of the top sheet of said bound sheets.

11. The method of binding sheets together to form a booklet comprising the steps of stacking the sheets to be bound with the sheets in order, offsetting the inside edge of each sheet with respect to the adjacent sheet with the edge of the first sheet in the booklet at the bottom to expose a narrow portion of the rear surface of each sheet and the edge, applying a length of binding tape having a coating of pressure sensitive adhesive on one surface along the offset edges of the sheets with the adhesive contacting said narrow portion of the rear surface of each sheet and a portion of the edge, placing a cover beneath the edges of the sheets, said cover having a front cover portion and a rear portion joined together along a fold line, aligning the inside surface of the front cover portion of said cover along the edge of the first sheet with the edge of the first sheet spaced from and parallel to the fold line, and pressing a marginal edge of the binding tape, adjacent to and extending parallel to the edge of the first sheet, to the inside surface of said front cover portion between said edge of the first sheet and the fold line.

12. The method of claim 11 wherein said aligning step comprises aligning the inside edge of the first sheet in the booklet with a guideline on the inside surface of said front cover portion and spaced from said fold line.

13. The method of claim 11 wherein said method includes the step of printing said guideline between about 0.8 and 3.2 mm from the fold line.

14. The method of claim 11 wherein said offsetting step comprises stacking the sheets in order with the first sheet on top of the stack and all the edges of the sheets aligned, clamping the outside free edges of the sheets against movement, moving the inside edges of the sheets to be bound over the clamped outside edges until the sheets form a curl and the inside edges of all the sheets are in shingled relationship.

15. A booklet comprising a cover for sheets having a front cover portion and a rear cover portion joined at a fold line to close toward each other and have an inside surface and an outside surface, a plurality of sheets disposed in said cover between the inside surface of the front cover portion and the inside surface of the rear cover portion, the first sheet of said plurality of sheets having an inside edge adjacent the inside surface of the front cover portion and spaced from the fold line and the remainder of said sheets being spaced a progressively greater distance from said fold line and from the first sheet, and a length of binding tape having an adhesive coated surface adhered to the edges of said plurality of sheets and a narrow portion of the rear surface of each of said sheets, and having a marginal edge of said binding tape adhered to the inside surface of the front cover portion between the inside edge of the first sheet and the fold line.

16. A cover-for covering and supporting sheets of bound paper in a booklet or brochure as claimed in Claim 1 substantially as hereinbefore described with reference to the accompanying drawings.

17. A method of binding sheets together to form a booklet as claimed in Claim 11 substantially as herein described with reference to the accompanying drawings.

18. A booklet as claimed in Claim 15 substantially as herein described with reference to the accompanying drawings.