GB2150883A

GB2150883A - A continuous blank letter form

Info

Publication number: GB2150883A
Application number: GB08430784A
Authority: GB
Inventors: Sampo Veikko Pellervo Salonen
Original assignee: TAMPEREEN KIRJAPAINO Oy
Current assignee: TAMPEREEN KIRJAPAINO Oy
Priority date: 1983-12-08
Filing date: 1984-12-06
Publication date: 1985-07-10
Also published as: SE8406232L; SE8406232D0; GB8430784D0; FI834490A0; FI834490A

Abstract

A continuous blank letter form (1) is composed of letters (2) to which letter form adhesive tracks (10) are provided for closure of the letters. The adhesive tracks are of cold-adhesive material so that the letter 2 can be closed by pressing the adhesive tracks together without heat process or moistening. The adhesive tracks are set onto successive letters of the continuous form, laterally moved within zones 8,9 so that they do not adhere together in a continuous form stack, or in a stack when detached as separate individual letters 2, but upon folding into an individual letter, the letter closes tightly together. The tracks 10 are laterally displaced in alternate letters 2. <IMAGE>

Description

SPECIFICATION A continuous blank form The subject of the invention is the continuous blank form defined in the introductory part of the Patent Claim.

As automatic data processing captures more and more territory in the office and technical fields it has become timely to develop many and more diversified blank forms of the so-called continuous form type for invoicing, customer notification and similar purposes. In the use of such continuous forms however, certain difficulties have manifested themselves in their processing and posting, because, amongst other reasons, one is reduced to using envelopes for the postage. It is true that the practice has been developed to close the continuous form as some kind of letter form. The most general means used in Finland for the closing of the letter form is to close it after folding by stapling.As a negative aspect of stapling it must however be confirmed that a form letter closed by stapling is for example unuseable in automatic postal sorting procedures, because the uneveness of the staple spike prevents operation of the automatic sorting equipment.

Further a recognised means of closing a form letter, for example as used in the Italian postal service, where the closure is made by a sticker adhesive, has the disadvantage that the contact surface can be opened and closed so that the recipient of the letter does not necessarily recognise that the privacy of correspondence has been invaded, which danger is also possible in the staple fastening method mentioned above, This fastening method using sticker adhesive is also presented in the Finnish Patent publication No 15 981, where it is put forward as a new matter and where the solution is a sticker fastening based on caoutchouc or natural latex-based adhesives. The patent publication mentioned claims that the envelope cannot be opened without leaving traces. This claim however is altogether erroneous.Caoutchouc-based adhesive does not permeate paper fibres with sufficient efficiency and the letter can be opened without leaving a trace. It must also be observed that the said adhesive type surface does not work in ADP outputting equipment because it rubs away with current equipment. Further it must be rea'ised that the caoutchouc- based adhesive seizes immediately on contact which cannot be held to be advantageous in the current form handling technique. It must be further realised that the caoutchouc-based adhesive material can be closed anew after opening.

Another recognised means of closing a form letter is by using adhesive tracks which adhere to one another under the influence of heat. However it must be here concluded that in such circumstances in which for example an answer to the form letter is required from the recipient, the hot adhesive method is not practicab!e. Likewise it has been verified when using the laser output method that it is unusable in practice because the temperature in excess of 200"C created by the said method means that the continuous form can no longer be closed by hand. In Finland the said hot adhesive method is used for example in bank and similar institution statements.

The purpose of the invention here put forward is to achieve a form letter, to be used in connection with automatic data processing and with which the aforementioned disadvantages of recognised form letters can be avoided.

For these facts characteristic to the invention the Patent Claim is referred to.

The invention is based upon a new kind of location of the adhesive tracks and a new adhesive composition.

The bonding material used in the adhesive tracks includes natural rubber latex, advantageously 75-85%, for example 79% acrylic acid ester mixed polymers, advantageously 15-25%, for example 20% and also of silicone emulsions advantageously 0.52%, for example 1%. The acrylic acid ester mixed polymer in the adhesive track is protected by the other elements of the material and upon closing of the form it permeates the fibres of the paper and into the fibres of the other corresponding adhesive track forming a bond, the strength of which is essentially greater than the surface strength of the paper used. Thus opening of the letter after the adhesive has dried cannot be made without leaving traces.

With the aid of the silicon emulsion the surface friction of the adhesive tracks can be reduced thus making stacking and printout in the ADP writer possible. Because of differences in the surface tensions of the styrene butadiene latex in the adhe-sive tracks and the acrylic acid ester mixed polymer the latex surrounds the mixed polymer with small adhesive droplets, which, when pressed disperse and permeate into the fibres of the paper and into the adhesive tracks.

When the aforementioned adhesive is used the form letters are easy to close by hand or by various equipment, which presses the adhesive tracks together. Because of its simplicity this means of closing the forms is noticeably faster. Compared for example with the use of the hot-melt adhesives it is possible to raise the closing speed many times. As a result of the positioning of the adhesive tracks the form letters do not adhere to one another during procesing, although they close easily when folded. Similarly an advantage of the invention compared with recognised techinques is the lessening of surface friction in the adhesive track by using in it silicon emulsion which makes the handling of the form letters faster and more certain in mechanical and laser typewriters and makes second handling possible and faster with cutting machines ard shredders.

In the following the invention is described more closely by referring to the accompanying drawings in which: Figure 1 shows cne way of performing the method according to the invention, when open Figure 2 shows a blank letter form in accordance with Figure 1 at the first folding stage.

Figure 3 shows a form letter according to Figures 1-2 in the final stage of folding together.

Figure 4 shows another manner of performance according to the invention partly folded.

Figure 5 shows a third way of making the form according to tne invention, open, and Figure 6 shows a form letter according to Figure 5 partly folded.

The continuous form 1 of Figure 1 is composed of form letters 2, which can be detached from each other along the perforated lines 3. In the pages of the form letter there are formaliners 4 which can be torn free along the perforated lines 5.

Inside the formaliners there are laterally opening strips 6 which are separated from the rest of the letter by peforated lines 7. The opening strip consists of the inner zone 8 and outer zone 9.

The form letter can be folded along the line A-A according to Figure 2 when the adhesive tracks 10 of the zone 8 adhere to one another thus closing the letter according to Figure 2. When folding the letter 2 along the line B-B as in Figure 3 to the other side of the letter, the adhesive tracks 11 in zone 8 meet each other and close the letter and it can be opened by tearing the opening srips 6 away along the perforated line 7.

The two-part form letter 12 of the Figure 4, in which the parts are of different sizes consists of the corresponding perforation lines 5 and 7, formaliners 4 and opening strips 6 and also of the zones 8-9 as in the form letter of Figures 1-3. In addition the letter form of Figure 4 includes the perforated lines 13, symmetrical to the folding line C-C on both sides of the line which separate a sealable part of a letter on both sides of the fold line. Similarly the letter comprises the transverse adhesive tracks 15 and also the adhesive-free part 17 between the transverse strips 15 and the lateral adhesive strips 16, when the lateral adhesive track 16 is in the outer zone 9.

When folding the form letter 12 along the fold line C-C the transverse adhesive strips 15 meet each other and the lateral adhesive tracks 16 overlap. By then squeezing the adhesive tracks suitably the letter adheres together and can be opened by tearing away the opening strips 6 along the perforated line" 7 and 13.

Figures 5-6 show a three-part form letter, which can be folded into an accordion-like letter. In the lateral adhesive tracks are set into the inner zone 8 and the transverse adhesive tracks connect the ends of the lateral adhesive tracks so that both sides of the form letter have a common adhesive track frame 18 and 19. On one side of the form letter there is a frame around parts A and B and on the other side of the letter around parts B and C.

When folding the form letter, accordion-like, along the folding lines D-D and E-E according to Figure 6 end pressing on the adhesive tracks the letter closes tightlv s?d can be opened by tearing the open ;ng strips e and 2O away along the perforated lines.

The form letters put forward in Figures 1-6, al :tough comprising with only a pressure the adhe s:ve tracks adhering to each other, can be kept similarlv to the continuous blank form in an accordion-like stack, zig-zag pile, or they can be torn apart, and all the forms can be stacked in a pile with the same side up. In other words the form letters can be stacked one upon the other by turns front sides opposite each other and other sides opposite each other or with the same side up. As the result of alternate setting of the lateral adhesive tracks into inner and outer zones the adhesive tracks do not touch each other except when folding a single form letter into its posting mode. Some applications of the invention are put forward above.Locating the adhesive tracks according to the invention and the cold adhesive according to the invention are however also possible to use in many other folding modes of continuous blank forms without in any way limiting the size or purpose of use. The applications of the invention thus put forward can vary within the boundaries of the concept of the invention. For example, the setting of the adhesive tracks is also possible so that in every other letter form, adhesive tracks are formed along one edge of the outer zone (9) (for example along the inner edge of the outer zone) and a further adhesive track is formed along the other edge of the inner zone (8) (in this example, along the inner edge of the inner zone) and along the other edge of the outer zone (in this example, along the outer edge of the outer zone).

Reference numbers given in the following claims have been added as an aid to the reader are not intended to limit the claims in any way.

Claims

1. A continuous blank letter form (1) which is composed of separate detachable letter forms (2, 12) and which can be folded and closed into letters, which letter can be opened by tearing the lateral (6) and/or transverse (14) opening loose and to which letter form adhesive tracks (10,11,15,18) are provided for closing the letter characterised in that the lateral opening sheets (6) of the continuous form (1) are provided with inner (8) and outer (9) zones so that the lateral adhesive tracks of every other letter form of the continuous form are in the outer zone (9) and in every second form in the inner zone (8), or in every other letter form of the continuous form, adhesive tracks are in one edge in the outer zone (9) and in the other edge in the inner zone (8) and in every second letter form of the continuous form respectively in one edge in the inner zone (8) and in the other edge in the outer zone (9) so that when folding a single form letter the adhesive tracks meet, but as a continuous form stack or in a stack of detached forms the adhesive tracks do not meet, and that the adhesive tracks are of a cold adhesive material, when the tracks adhere on opposition by pressure without any further handling, so that the letter cannot be opened without leaving traces.

2. A continuous blank letter form in accordance with Patent Claim 1 characterised in that the letter form (12) is provided with transverse adhesive tracks (15) whereupon there is an adhesive-free portion (7) in the region of zone (8), between the lateral adhesive tracks (16) and the transverse adhesive tracks (15).

3. A continuous blank letter form in accordance with Patent Claims 1 or 2 characterised in that a three-part letter form is composed of two fundamentally common adhesive track frames (18,19) one surrounding the central part and one end part, and the other surrounding the central part and the other end part on the other side of the paper.

3. A continuous blank letter form in accordance with Patent Claims 1 or 2 characterised in that a three-part letter form is composed of two fundamentally common adhesive track frames (18, 19) one surrounding the central part and the one end part, and the other surrounding the central part and the other end part on the other side of the paper.

4. A continuous blank letter form according to some of the Patent Claims 1-3 characterised in that the adhesive material within the cold adhesive material track is in protected form so that upon pressure it comes out to permeate the paper and the other adhesive track to form a bond, the strength of which is greater than that of the surface strength of the form paper.

5. A continuous blank letter form according to Patent Claim 4 characterised in that the adhesive material is of acrylic acid ester mixed polymer material which is surrounded with a styrene butadiene latex in droplet form to make the adhesive track.

6. A continuous blank letter form according to Patent Claims 4 or 5 characterised in that the adhesive track includes silicon emulsion, which reduces the surface friction of the adhesive track.

7. A continuous blank letter form in accordance with some of the Patent Claims 4-6 characterised in that the cold adhesive material includes 60-90% styrene butadiene latex, advantageously 70-85% for example 77-81%, acrylic acid ester mixed polymers 10-30%, advantageously 15-25%, for example 18-22% and also silicon emulsion 0.1-3%, to advantage 0.5-2%, for example 0.9-1.2%.

8. Continuous feed blank letter forms consisting of a stack of detached or detachable forms which can each be folded and sealed into a postable letter, wherein each letter from has at least one pair of removable sealing strips that are coated with paper-permeating contact adhesive, the adhesive being disposed in discrete zones in such an arrangement that each letter form is foldable to bring the adhesive zones of the strips of each pair of strips into contact to seal the letter form but the disposition of adhesive zones in the letter forms is such that the adhesive zones of one letter form do not, in the stack, lie against the adhesive zones of the immediately adjacent letter forms.

9. Continuous feed letter forms substantially as hereinbefore described in connection with, and with reference to, Figures 1 to 3, Figure 4 or Figures 5 and 6 of the accompanying drawings.

Amendments to the claims have been filed, and have the following effect: (a) Claims 1 & 3 above have been deleted or textually amended.

(b) New or textually amended claims have been filed as follows: CLAIMS

1. A continuous blank letter form (1) which is composed of separate detachable letter forms (2, 12) and which can be folded and closed into letters, which letter can be opened by tearing the lateral (6) and/or transverse (14) opening loose and to which letter form adhesive tracks (10, 11, 15, 18) are provided for closing the letter characterised in that the lateral opening sheets (6) of the continuous form (1) are provided with inner (8) and outer (9) zones so that the lateral adhesive tracks of every other letter form of the continuous form are in the outer zone (9) and in every second form in the inner zone (8), or in every other letter form of the continuous form, adhesive tracks are in one edge in the outer zone (9) and in the other edge in the inner zone (8) and in every second letter form of the continuous form respectively in one edge in the inner zone (8) and in the other edge in the outer zone (9) so that when folding a single form letter the adhesive tracks meet, but as a continuous form stack or in a stack of detached forms the adhesive tracks do not meet, and that the adhesive tracks are of a cold adhesive material, when the tracks adhere on opposition by pressure without any further handling, so that the letter cannot be opened without leaving traces.