CA1226011A

CA1226011A - Business forms with label release coating and formulation for use therewith

Info

Publication number: CA1226011A
Application number: CA000401109A
Authority: CA
Inventors: Hugh B. Skees
Original assignee: Standard Register Co
Current assignee: Standard Register Co
Priority date: 1982-04-16
Filing date: 1982-04-16
Publication date: 1987-08-25

Abstract

ABSTRACT OF THE DISCLOSURE
A method of producing business forms which comprises moving a continuous strip of business form material through a printing press and printing visible indicia upon the strip and also printing label release material on spaced-apart portions or the strip for the receipt of labels thereupon. This invention also includes the composition of a label release material.

Description

Jockey: 2500 Hugh B. Skies 2 BUSINESS FORMS WITH LABEL RELEASE COATING
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AND FORMULATION FOR USE THEREWITH

Field of the Invention , The present invention relates to business forms having adhesive labels releasable adhered thereto and to improved methods of manufacturing such forms. The present invention further relates to release coating ink compositions for use in such methods.

Background of the Invention Business forms are usually produced from a continuous strip or web. A series of printed areas are formed upon the lo strip or web as the strip or web moves through a convention-at printing press. The strip or web is then severed or perforations are formed along transverse lines between sue-cessive printing areas to provide a plurality of separate or individual business forms.
Some types of business forms are provided with at least one removable label in conjunction with the printed areas. A label is applied to the form as the continuous web travels. The labels are ordinarily applied as label units in a separate operation after the strip has been printed.
Conventionally, each label unit has a base portion which is permanently adhesively attached to the strip or web, and each base portion has a label portion which is releasable attached to the base portion. The surface of the base portion on which the label portion is attached is conventionally I' ~ockeL 2566 I 2 6 011 coated with a release coating to allow easy removal of the label portion therefrom. The surface of the label portion facing the release coating conventionally has a pressure sensitive adhesive thereon. After severance of the individual business form from the continuous strip, the label portion is ordinarily removed from each individual business form for application to another surface by the forms user. Such structure has the principal objection that the base portion has a dimension above the surface of the form and remains on the business form after the label portion is releasable removed therefrom. Another disadvantage is the high cost of the required use of labels of two-ply laminated construction.

Summary of the Invention Accordingly it is an object of the present invention to eliminate the deficiencies of the prior art, such as those set forth hereinabove It is another object of the present invention to provide an improvement in business forms having both printing and removable labels thereon.
It is yet another object of the present invention to provide an improvement in release coating compositions so that they may be usable in conventional printing processes.
It is still another object of the present invention to provide an improved method of applying release coating to business forms.
It is a further object of the present invention to provide a business form and a method of making such a business form having removable labels thereon without base portions remaining on the business form after the label is removed.

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It is yet a further object of the present invention to provide a business form and a method for making such a business form which is produced in a continuous strip in which small areas of release coating material are applied by the printing apparatus as the business forms are printed and in which a label with a pressure sensitive adhesive is then applied to the area which has been coated with the release coating.
Still other objects features and attendant ad van-taxes of the present invention will become apparent to those skilled in the art, from a reading of the following detailed description of the embodiments in conjunction with the attached drawings.

Brief Description of the Views of the Drawings Figure 1 is a perspective view of prior art structure showing a portion of a continuous web which has a series of printed areas and illustrating the application of a label unit to the continuous web, as a label unit is applied to ! each of the printed areas.
Figure 2 is a fragmentary perspective view of the prior art structure and method of Figure 1, drawn on a larger scale than Figure 1, showing a portion of the continuous web of Figure 1 and illustrating the manner in which a label portion is removed from a base portion of a label unit.
Figure 3 is a perspective view, drawn on substantially the same scale as Figure 1, illustrating a continuous web having a series of printed areas with a release coating of this invention applied to a portion of each printed area.

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2 Russ view also illustrates the application of a label Jo the release coating pout on of ear. of the printed areas.
Figure 4 is a fragmentary perspective view, Doria.
on substantially the save scale as Figure 2, showing a portion 5 of the continuous web o. figure 3, and illustrating rival of a label from a potion thereof to which a libel release coaxing has been applied.

Detailed Description o, the Invention.
Figure 1 shows a portion ox a continuous we 10 which lo has a series o. spaced-apart score lines 12 which separate the web 10 into a series of sections 14~ Each section 14 has rinsed maser applied thereto by means of a conventional printing press as the continuous web 10 lovelies horrify A label unit 16 is applied to a portion 18 of each section 15 ,14 of the continuous web 10. Each label unit lo co~p~lses a base portion aye and a label portion 16b. The base portion aye has a release coating 20, such as a silicone puller, on its front face. Its back face is secured to the web 10 by a suitable adhesive 22. The label portion 16b has a pressure sensitive adhesive 24 on the Lear surface thereof and is releasable adhered to the base portion aye by means of the release coating 20 on the base portion aye.
Figure 3 illustrates a portion of a continuous web 30, produced in accordance with the present invention.. The web 30 has a series of transverse score fires or separation lines 32 which separate the web 30 into a series of sections 34. The sections 34 are printed upon as the continuous web 34 travels through suitable printing apparatus, not shown.

Docket 25~6 I 6 The printing apparatus applies visible ink in the form of indicia and/or lines 35, and the like to each of the sections 34. At the same time, the same printing apparatus also applies a visible or invisible release coating to a relatively small port lion 38 of each of the sections 34. Thus, a label 40 having pros-sure sensitive adhesive material 42 on the lower surface thereof is releasable attached subsequently to the portion 38 of each of the sections 34.
In order to apply the release coating to each portion 38 by means of a conventional printing apparatus, the release coating material must be formulated into an ink suitable for the printing process of choice, such as letter press or dry offset printing. Such an ink is preferably formulated with reactive silicone prepolymers (for example, polydimethylsiloxanes), and other ingredients, so that after the ink, in its fluid state, is applied to each portion 38, a chemical reaction occurs, cross-linking the silicone prepolymer and converting it from the fluid to the solid state. The cured layer of ink thus functions as a normal release surface for a pressure sensitive adhesive label in the same way that a conventional release liner does. After the solid silicone polymer forms (2 to 5 days under ambient conditions), the web 30 is fed through a label attaching device (not shown) and a label 40 is affixed to each polymer-coated portion 38.
The single ply labels 40 are now adequate. Subsequently, the sections 34 are separated along the separation lines 32, and the sections 34 thus constitute business forms and are adapted for mailing or other use. The person who uses a section 34 is expected to remove the label 40 therefrom. After removal of the label 40, there is no remaining label-si~ed base or piece of material remaining on the section 34.
A practical release coating or ink suitable for printing must have the proper viscosity, tack and length. It is also desire able that such an ink contain no solvents or delineates. Thus, it Docket 2566 ~260~

is preferred, although not critical, to print a release coating ink which is "100% solids" so that it is not necessary to vaporize solvents by heating, or to interfere with the release properties of the cured polymer by the presence ox materials which remain liquid after the curing reaction occurs.
A printing ink suitable as a release coating in the present invention is made according to the following sequence of steps:
A. Determine the physical properties required by the printing process to be used.
B. Select the type of release coating desired.
C. Tailor the physical properties of the release coating to conform to the requirements of the desired printing process by combining the chosen pressure-sensitive adhesive release material with other materials.
The first of these steps is to determine the physical properties required by the printing process to be used. The printing process is determined by the printing equipment available (letter press, transfer letter press, flexographic, or Grover, etc.). The most commonly used equipment is letter-press or dry offset apparatus. The pertinent physical properties of the release coating ink include viscosity, tack, length, etc.
(See, for example, The Printing Industry, Victor Strauss, Printing Industries of America and R. R. Bowler Co., New York, (1967, pp.
582-3). The physical properties required by any given printing process, as determined by the particular printing equipment used, are well known to those skilled in the printing arts.
The second step is to select the type ox release coating desired. A fairly wide range of chemical types are recognized by one skilled in the art of release coatings.

socket 2566 These coatings have been developed for the manufacture of full coated "release liner" stock and are used commercially in large quantities in such coating processes as air knife, Mayer rod, reverse roll, kiss, etc. However, none of these materials has ever been adapted for selective area printing by incorporation into a printing ink suitable for imparting good pressure-sensitive adhesive release.
The most widely used class of release materials are the organo-silicone polymers (e.g., polydimethylsiloxanes) although other types may be used. These are usually menu-lectured as polymeric liquids or prepolymers which cure to high molecular weight solids when combined with a proper cross-linking agent and/or catalyst. One convenient type of silicone prepolymer reacts with moisture absorbed from the surrounding atmosphere. If the prepolymer contains the proper catalyst, the absorbed water molecules function as a cross-linking agent. The curing action is usually accelerated by heat. The rate of the cross-linking reaction is influenced by the identity of the prepolymer, the cross-linking agent and catalyst chosen, and the temperature of the mixture during cure. The reaction rate must be slow enough that the formulated ink will remain fluid long enough for the printing operation. That is, the ink must not become solid on the rollers and in the fountain of the printing press. An "open time" of 6 to 8 hours at ambient temperatures is adequate. However, the reaction must be fast enough that complete cure can be achieved under practical conditions.
Heat can be applied to accelerate cure, but it is preferred that cure will be complete at ambient temperatures within one week or less.
Some examples of materials used commercially for full web coating operations are:

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Polymeric Liquid Catalyst Available as Manufacturer Sulfa 294 * 23 A solvent solution Dow Corning Corp.
Sulfa 23 * C4-2117 solvent solution Dow Corning Corp.
Sulfa 22 * 22-A aqueous emulsion Dow Corning Corp.
Sulfa 1171 * Q2-7014 aqueous emulsion Dow Corning Corp.
Sulfa 1107 * ZOO 100~ reactive Dow Corning Corp.
Sulfa 7044 * Sulfa 7048 100% reactive Dow Corning Corp.
SO 4300 * SO 4300C 100~ reactive General Electric Co.
SO 4315 * SO 4300C 100% reactive General Electric Co.
Even though solvent less, 100% solids materials are preferred and are best suited for letter press and dry offset printing processes, solvent and emulsion types are included in this list because these are better suited starting materials for formulating flexographic Grover inks.
Disclosure and chemical description of such materials may be found, for example, in US. patents 4,123,604, 3,527,659,

3,565,750, 3,565,838 and 3,770,687. Other non-silicone types of release materials may also be used in the present invention as, for example, assaulted polyethyleneamines described in US. patent 3,510,342, US. patent 3,475,196 and US. patent 3,394,799;
arylamine doomed of fatty acid described in US. patent 3,282,727;
and stroll methacrylate-acrylo-nitrile copolymers described in US. patent 3,502,497. Also useful are powdered polyethylene (US. patent 3,218,1~5) and combination of polyvinyl alcohol and Warner complex fluorocarbons (US. patent 3,690,924).
After the type of release coating is selected, the physical properties of the composition should be tailored to conform to the requirements of the desired printing process by combining the chosen release materials with other materials.
These other materials must not only impart the desired physical properties to the final ink formulation, but must not interfere I

chemically with the curing of the polymeric liquids, not interfere to a significant degree with the adhesive release properties of the cured ink nor interfere significantly with the adhesive properties of the label when it is removed and applied to another surface. Examples of such other ink ingredients are:
1. For increasing viscosity and body without increasing tack; pigments such as clays, metal oxides and carbonates, fumed silicas, aluminum silicate and other inert solid particulate.
A particularly preferred such pigment is Aerosol 972*, made by Degas, Inch This is a hydrophobic fumed silica pigment material.
2. For increasing viscosity, body and tack together:
a. Polymers and resins soluble in the polymeric release material. Such polymers and resins must not interfere with the cross linking reaction which cures the release material.
They may be polymers and/or resins soluble in the polymeric liquid itself, or in the delineate solvent or water which acts as a carrier for the release material. Examples are polystyrene; styrene-butadiene copolymers; polyacrylates and copolymers thereof; hydrocarbon resins; methyl cellulose;
terrapin resins; and vinyl resins such as polyvinyl acetate, polyvinyl alcohol and polyvinyl-stearate.
b. A polymeric liquid may be partially pre-reacted with a portion of its cross linking agent prior to the final step when the ink is prepared for immediate use. This results in increasing the molecular weight of the polymeric fluid, thus increasing its viscosity * Trademark ~L2Z6~

3. For decreasing viscosity, body and tack:
a. Solvents miscible with the polymeric release material or with its solvent carrier, such as hydrocarbons, chlorinated hydrocarbons, ethers, esters, or aromatics may be used to decrease viscosity, body or tack. Specific examples include hexane, trichloroethylene, ethylene glycolmonomethyl ether, bottle acetate and Tulane.
b. Water, in the case of the aqueous emulsions, may be used.
The ingredients chosen or tailoring the physical properties of the ink can vary widely, depending on the skills and preferences of the formulator. It is not the intention here to limit this invention to specific examples or classes of property-modifying ingredients. It is sufficient that materials are chosen which, together with the polymeric liquids, curing agents and catalysts, provide an ink with suitable physical properties for the selected printing process, while at the same time providing a cured coating with the desired adhesive release properties.
The process of combining all the ingredients into a completed ink can also vary widely, depending on the materials chosen and the formulator's preference. However, the preferred method is to blend the polymeric fluid with the viscosity modifying agent, using a mechanical stirrer. When a homogeneous mix is obtained, then other ingredients, such as tack modifiers, are added. The final addition is the cross linking agent and/or catalyst, which is not added until immediately before the ink is put into the printing fountain. This assures maximum pot life and open time in the press.

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A preferred embodiment of the present invention is given in the following example (all parts by weight):

Example 1000 parts Sulfa 704~ were mixed with 12 parts Sulfa 7048 and heated to 80-100C for 10 to 15 minutes.
This caused partial cross linking of the organo~silicone prepolymer, increasing its viscosity and tack. After cooling to 20-30C, 90 parts of Aerosol 972 were stirred in by mechanical, slow speed agitation. This step further increased viscosity without further increasing tack. This mixture may be stored indefinitely at ambient temperatures without change. When ready for use, an additional I parts of Sulfa 7048 were added thoroughly mixed in and kept at ambient temperature. This ink was printed by letter press and by transfer letter press on business forms bond paper in the form of spots or areas slightly larger than the intended label. The ink had a pot life and press open time of 10 hours. The printed roll of paper was allowed to age for 4 days at ambient temperature, after which time the applied ink had cured to solid, rubbery release coating.
When permanently open acrylic and hot melt pressure sensitive labels were applied to the coated area, they could be easily peeled off. when these peeled off labels were applied to untreated surfaces, they developed normal tack, producing fiber-tearing bonds when applied to paper.
Sulfa 7044 is a solvent less polymeric release coating sold by Dow Corning Corp. having the following structure:

/ SHEA / f 3 Ho- So - 0/ - - So - 0 - H

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clue, 2566 2 I 1 ~2-7045 crosslinkirig agent is a polymethyl hydrogen selection, sold by Dow Corning Corp., having tune hollowing structure:

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IL will be obvious Jo those swilled in ho art Tut various changes aye be jade withal departing from he Scope GO- the inven~ion9 an the invention is no o be eon.-sodded limited LO wow is shown in the drawings arid desk cribeG if. the specification.

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Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

1. A business forms assembly comprising:
an elongate web of sheet material, a series of spaced-apart transverse lines of weakening along the length of the elongate web and separating the web into a series of connected separable business forms, each business form having printed indicia applied thereto, each business form having label release coating material applied thereto and covering only on a small portion thereof, a plurality of labels, the area of each of the labels being relatively small compared to the area of the business form, there being a label releasably attached to each small portion of the business form, all other portions of the business form being uncoated and uncovered, so that when the label is removed from the business form the only covering upon the business form being the label release coating material.

2. The method of producing a business form comprising printing visible indicia upon a substantial portion of the total area of a sheet of business form material, while simultaneously applying label release coating material to cover and coat only a small portion of the total area of the sheet, leaving all other portions of the sheet uncoated and exposed to provide for observing the indicia, applying a label to the sheet, the label having pressure sensitive adhesive material covering one surface thereof, the label being directly attached by the pressure sensitive adhesive material to said label release material which covers and coats said small portion of the total area of the sheet, the label being adapted to have visible information applied to the surface thereof opposite the surface which is covered by the pressure sensitive adhesive material, and the label being removable from the sheet and attachable to another surface by means of the pressure sensitive adhesive material.

3. The method of producing a business form comprising: printing upon a web of sheet material having a series of spaced-apart transverse lines of weakening along the length of the web, the transverse lines separating the web into a series of connected separable business forms, printing visible indicia upon each business form over a substantial portion thereof while simultaneously applying label release coating material to cover only a small portion of the total area of each business form, applying a plurality of labels to the web in which each label has pressure sensitive adhesive material covering one surface thereof, including directly attaching one of the labels to each business form of the web by means of the pressure sensitive adhesive material which is carried by the label, the label covering at least a portion of the label release material which covers said small portion of the total area of the business form, the label being removable from the business form and reattachable to another surface by means of the pressure sensitive adhesive material which covers said one surface of the label.

4. A business form comprising a sheet of business form material, the sheet having a given area, the sheet having visible indicia printed thereon over portions of a substantial part of the given area of the sheet, label release coating material covering only a small portion of said given area of the sheet, all other portions of the sheet being uncoated and uncovered, a label covering at least a part of each small portion of said given area which is covered by label release coating material and releasably attached thereto.

5. A business form comprising a sheet of business form material, the sheet having a given area, the sheet having visible indicia printed thereon over portions of a substantial part of the given area of the sheet, label release coating material covering only a small portion of said given area of the sheet, all other portions of the sheet being uncoated and uncovered, a label having a contact surface, pressure sensitive adhesive material carried by the contact surface, said contact surface of the label releasably adhering to the label release coating material which is applied to said small portion of the sheet, the label being removable from the sheet and being reattachable to another surface by means of the pressure sensitive adhesive material which is carried by the contact surface.

6. The business form of Claim 5 in which the label has a surface opposed to the contact surface, the opposed surface of the label having indicia printed thereon.

7. The business form of Claim 5 in which the label covers a substantial part of the area covered by the label release coating.

8. A business forms assembly comprising: an elongate web of sheet material, a series of spaced-apart transverse lines of weakening along the length of the elongate web and separating the web into a series of connected separable business forms, each business form having printed indicia applied thereto, each business form having label release coating material applied thereto and covering only a small portion thereof, a plurality of labels, the area of each of the labels being relatively small compared to the area of the business form, there being a label releasably attached by means of pressure sensitive adhesive material to each small portion of the business form, all other portions of the business form being uncoated and uncovered, so that when the label is removed from the business form the only covering upon the business form being the label release coating material, the label being removable from the business form and attachable to another surface by means of the pressure sensitive adhesive material.

9. A business form comprising a sheet of business form material, the sheet having a given total area, the sheet having visible indicia printed thereon over a substantial portion of the total area of the sheet, label release coating material covering and coating only a small portion of the total area of the sheet, the label release coating material being adapted to be applied to the sheet as the indicia is being printed upon the sheet, all other portions of the sheet being uncoated and exposed to provide for observing the indicia, a label having a pair of opposed surfaces, pressure sensitive adhesive material covering one surface of the label, the label being directly attached by the pressure sensitive adhesive material to said label release material which covers and coats said small portion of the total area of the sheet, the label being adapted to have visible information applied thereto on the surface thereof opposite the surface which is covered by the pressure sensitive adhesive material, and the label being removable from the sheet and attachable to another surface by means of the pressure sensitive adhesive material.

10. A business forms assembly comprising: a web of sheet material, a series of spaced-apart transverse lines of weakening along the length of the web and separating the web into a series of connected separable business forms, each business form having printed indicia applied thereto over a substantial portion thereof, label release coating material covering and coating only a small portion of the total area of each business form, the label release coating material being adapted to be applied to the business form as the indicia is being printed upon the business form, a plurality of labels, pressure sensitive adhesive material covering one surface of each of the labels, each label being directly attached by the pressure sensitive adhesive material to the label release material which covers and coats said small portion of the total area of one of the business forms, each label being removable from the business form and attachable to another surface by means of the pressure sensitive adhesive material which covers one surface of the label.