JPH0497897A - Leaf filing cover - Google Patents

Abstract

PURPOSE:To eliminate such a phenomenon that the paper piece being in contact with or close to a front (back) cover is not thermally bonded even when bookbinding Ls carried out using a large or small number of text papers in spite of a low cost coating means by setting the difference between the thickness of the hot melt adhesive layer applied to a back part at a specific position from both ends of the back part and max. thickness thereof to a specific range. CONSTITUTION:The hot melt adhesive layer 4 is formed on the inside of a back part 2 using a hot melt adhesive so as to draw curved surfaces at both ends of the back part 2 to form recessed parts 6, 6 between the adhesive layer and front and back covers 1, 3. The thickness of the hot melt adhesive layer 4 at the position 8 where the max. width 7 from each of both ends of the back part 2 of the hot melt adhesive layer 4 is 160 mu is calculated to be set to X and the max. thickness of the hot melt adhesive layer 4 is calculated to be set to Y. When the max. difference between Y and X at this time is Y-X=250mu and the min. difference between them is Y-X=0, even when a small number of that papers 5 are filed in the cover having the hot melt adhesive layer 4 formed thereon, no text papers not thermally bonded are generated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a heat-melt adhesive layer (hereinafter, a heat-melt adhesive layer is simply referred to as a "thermal adhesive layer"), It consists of a spine which has a heat-melting adhesive (simply referred to as thermal adhesive) on the inside by applying means, and a front cover and a back cover that are connected to this spine, and the text paper is adhered by the heat-melting of the thermal adhesive on the spine. Concerning the neatly bound paper leaf bound cover.

[Prior Art] The paper consists of a spine, a front cover and a back cover connected to the spine, and a thermal adhesive layer is formed on the inside of the spine by a coating means. There is no need to exemplify a paper sheet binding cover that is bonded together by melting (it is known).

Alternatively, the thermal adhesive layer can be formed by preparing a strip of thermal adhesive without using an application method, and attaching a strip of thermal adhesive with a size corresponding to the width of the back to the inside of the back, or by applying thermal adhesive. It has also been done to form a thermal adhesive layer.

[Problems to be Solved by the Invention] Among these, in the latter case, as shown in Section 2 and FIG. , since it is glued or heat-sealed to the back 2, when the front cover 1 and back cover 3 are folded,
The surface of the thermal adhesive layer 4 is smooth, and the thickness of the thermal adhesive layer 4 is maintained at the same level even in the areas where this layer 4 contacts the front cover 1 and the back cover 3. It is preferable that the thickness of the thermal adhesive layer 4 is kept at the same level across the spine 2, since the body paper 5 is neatly heat-fused to the spine 2 during bookbinding. This too has its drawbacks. If the back part 2 is wide, it is easy to glue a strip of hot adhesive layer cut to a certain width to the inside of the back part, but if the back part 2 is narrow, In the case of a cover made of several sheets of text paper, it is not easy to attach a strip of thermal adhesive to the spine (it is difficult to commercialize it, and it is difficult to commercialize it). In this case, the product will inevitably be expensive.

On the other hand, forming a thermal adhesive layer by applying a thermal adhesive layer to the back is technically easier and has the advantage of being possible at low cost, but of course this also has its drawbacks. be. To explain this using Figures 4 to 6,
Open the cover and apply hot glue to the front cover 1, spine 2, and back cover 3.
However, since the thermal adhesive is applied after being heated and its viscosity is lowered, both ends of the thermal adhesive layer 4 are applied in a flat state from the area of the back 2 to the front cover 1. It may even flow to the back cover 3 and solidify. The heat-dissipating adhesive must form a layer within the area of the back 2, and this heat-dissipating adhesive layer 4 must be formed as shown in FIG. A deep recess 6.6' is formed.The existence of this recess 6.6' cannot be said to be a decisive problem when binding a book consisting of a large number of body papers 5, but when the body paper 5 is a small number. When binding a book consisting of sheets, a phenomenon was observed in which all the text sheets 5 were not thermally bonded.

This is because of the text paper 5 placed on the thermal adhesive layer 5,
The text paper at the position of the recess 6.6' moves diagonally on the thermal adhesive layer, and the text paper comes into contact with the thermal adhesive layer. It was found that since it was located at a high position in the recess, it was not heat-sealed because it was located at a deeper position toward the other end of the recess, that is, at a position in contact with the front (back) cover.

In this invention, when applying a thermal adhesive to the back to form a thermal adhesive layer, it is unavoidable that this recess will occur, but in what condition should the thermal adhesive layer be formed? This was done with the aim of eliminating the shortcomings.

Means for Solving Problems in Section 1] In order to achieve the above-mentioned object, the present invention consists of a spine having a thermal adhesive layer on the inside, and a front cover and a back cover that are connected to this spine, and the text paper is attached to the spine. The outer adhesive layer on the inside of the spine of the paper bound cover, which is bonded by heating and melting to the thermal adhesive layer of When the thickness of the thermal adhesive layer at the position of 160μ is X, and the maximum thickness of the thermal adhesive layer is Y, the difference between Y and X should be 250μ or less and within the range of Ou. By doing so, I was able to achieve the purpose I had stated above.

When a thermal adhesive layer that satisfies these conditions is formed, even if the back width is narrow, about 1 mm,
The small number of sheets of paper that are bound into this book can now be completely heat-fused together. In addition, even if the width is less than this, can you use hot glue? All that is required is a heat-receiving area from the hot melter that melts δ.

In the present invention, the overall thickness of the thermal adhesive layer is preferably about 300 μm to 1 mm, but as long as the capacity of the hot melter during bookbinding is sufficient, it may be as thick as fiLu.

Further, the negative adhesive used in this invention may be any commonly used thermal adhesive (but is not limited to a specific one).

[For use] The adhesive layer 4 formed by applying hot adhesive to the back of the cover does not have a uniform thickness in each part on the back 2,
It is formed with a curved surface in the width direction. This curved surface forms a recess 6.6' which is the deepest space at both ends of the back part 2, and this recess causes non-adhesion of the text paper, but if this recess is shallow and the iφ slope is gentle, no adhesion will occur. However, if the recess is deep and has a strong slope, it will cause non-adhesion.These limits are determined by determining the thickness of the thermal adhesive layer at a position with a maximum width of 160 u from both ends of the back. When X is the maximum thickness of the thermal adhesive layer and Y is the maximum thickness of the thermal adhesive layer, all of the sheets will preferably be bonded even if there is a small number of text papers as long as the difference between Y and X is within the range of 250u or less. It became.

Note that the difference between Y and X is OU, which is 160u from both ends of the back.
This means that the point is not a curved surface, but a plane that is the same as the maximum thickness of the thermal adhesive layer.

[Example] Next, an example of implementing the present invention will be explained with reference to the attached 1-size drawing. 1 is a front cover, 2 is a spine, and 3 is a back cover, and the 1 front cover l and the back cover 3 are provided in succession on the spine 2.

Reference numeral 4 denotes a thermal adhesive layer formed by applying thermal adhesive to the inside of the back portion 2 (IM1). Reference numeral 5 denotes a text sheet that is heat-adhered and bound to this cover. Since the thermal adhesive layer 4 is formed with a curved surface at both ends of the back 2, the front cover 1
A recess 6 is formed between the front cover and the back cover 3, and a recess 6' is formed between the back cover and the back cover 3.

The thickness of the thermal adhesive layer 4 formed in this manner is measured at a position 8 having a maximum width 7 of 160 u from both ends of the back part 2 inwardly, and this thickness is designated as X. Also, the maximum thickness of the thermal adhesive layer 4 is measured and this thickness is designated as Y. The difference between Y and X at this time, that is, the maximum is Y −, X = 250
If μ is within the range where the minimum is Y-X=O, even if a small number of sheets of text paper 5 are inserted into the cover on which the thermal adhesive layer 4 is formed, the text paper will not be thermally bonded and the text paper will not be formed. (A satisfying 41-inclusion state is obtained.

[Effect of the invention 1] When using the cover on which the thermal adhesive layer described in detail above is formed, when a large number of body papers are used; of course, when using a small number of body papers such as several Even when the book is bound using a transfer adhesive, each piece of paper is completely adhered to the front (back) cover, and there is no problem in which the paper pieces that are in contact with the front (back) cover or close to this are not thermally bonded. It is a low cost method to form by coating means,
It is now possible to easily bind not only a large number of body sheets but also a small number of body sheets, which was considered difficult in the past.

[Brief explanation of the drawing]

The accompanying drawings are for explaining the present invention. Figure 1 is a side view of a cover showing an example of the implementation of the present invention, and Figures 2 and 3 are a conventional cover that is different from the present invention. This is just to explain the formation of the adhesive. Figure 2 is a side view showing the cover in an unfolded state, Figure 3 is a side view showing the cover in a folded state, and Figure 4 is a side view showing the cover in a folded state. AI-Figure 6: This is to explain the formation of the thermal adhesive layer by the coating means. It is a side view showing the folded state of the 5th section. 1 front cover, 2 spine, 3 back cover, 4 ?l! adhesive layer, 5 text paper, 6.6 recessed part 7 maximum width, X
Thickness of outer adhesive layer at maximum width position, maximum thickness of YPII adhesive layer

Claims (1)

[Claims] A paper that is made up of a spine having a heat-melt adhesive layer on the inside, and a front cover and a back cover that are connected to this spine, and is bound by bonding text paper to the heat-melt adhesive layer on the spine by heating and melting. In the leaf binding cover, the hot-melt adhesive layer on the inside of the back is formed by an application means, and the thickness of the hot-melt adhesive layer at a position with a maximum width of 160 μm from both ends of the spine inwardly. When is X and the maximum thickness of the hot-melt adhesive layer is Y, the difference between Y and X is 2.
A paper leaf binding cover characterized in that it is formed to have a thickness within a range of 50μ or less to 0μ.