Envelope

Abstract

A plurality of air relief holes 18 for removing air in a bag are formed in a slit shape at a portion where, when an opening portion of an envelope 10 is sealed by a seating portion 11a, the air relief holes are concealed by the sealing portion and which is an upper end portion of a second back face 14 of the envelope 10. In case that the envelope 10 is inserted between a pair of upper and lower pressure-contacting rollers from its bottom portion, when the envelope 10 passes through between the pair of upper and lower pressure-contacting rollers rotating in a manner sandwiched therebetween, air staying in a bag of the envelope 10 is exhausted from the air relief holes 18 to the outside, so that the envelope 10 is changed in one sheet shape. Thereby, forces acting on upper and lower faces of the envelope 10 from the pair of upper and lower rollers becomes approximately even, so that occurrence of wrinkles on the envelope 10 is suppressed. Thereby, the envelope 10 is moved straightly up to a printing position, and predetermined printing can be applied to a predetermined portion of the envelope at the predetermined position. Accordingly, predetermined printing can be applied to an envelope without depending on a printing machine or the like and without causing a wrinkle on the envelope and making printing inaccurate.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an envelope in which a document or the like is enclosed and whose an opening portion at an upper end is sealed, and in particular to an envelope which is suitable for printing performed by a printing machine, a copier, a printer, or the like.

2. Description of the Related Art

FIG. 8 is a view showing one example of a conventional envelope. An envelope 100 is formed by folding a sheet-like paper, and it includes a surface piece 101, first back pieces 102 and 103 provided to continue into both left and right side edges of the surface piece 101, and a second back piece 104 provided to be continue into a lower end of the first surface piece 101.

Briefly explaining a manufacturing process of the envelope 100, an envelope sheet member 100A that integrally includes the surface piece 101 having a sealing portion 101a, the first back pieces 102 and 103, and the second back piece 104 and that has been developed in a sheet shape is punched out from a sheet-like paper by a press cutting machine. In FIG. 8, the first back pieces 102 and 103, and the second back piece 104 shown by a double-dotted line show their developed states. At a punching-out time, scores (not shown) are formed at boundary portions between the surface piece 101 and the first back pieces 102 and 103 and between the surface piece 101 and the second back piece 104, respectively.

Thereafter, the first back pieces 102 and 103 and the second back piece 104 are folded to a back side along the scores and portions 102a and 103a of the first back pieces 102 and 103, and the second back piece 104 and the first back pieces 102 and 103 that overlap with each other at their back sides are pasted to each other using adhesive such as glue. Thereby, a lower end and both side portions of the envelop sheet member 100A are closed so that a bag-shaped envelope 100 with an opened upper end is formed.

FIGS. 9A and 9B are a front view and a side view for explaining a printing step of an envelope. That is, FIGS. 9A and 9B show a conveying path of the envelope 100 when printing is performed on the envelope 100 formed in a bag shape such as shown in FIG. 8 by a printing machine, a copier, a printer, or the like (hereinafter, collectively called “printing machine or the like”). When the envelope 100 is conveyed to a printing position, the envelope 100 is caused to pass through between a pair of upper and lower pressure-contacting rollers 105a and 105b rotated in the printer or the like in a manner sandwiched therebetween, and it is conveyed in a direction of arrow in FIG. 9B according to rotations of the pressure-contacting rollers 105a and 105b, so that printing is performed on one side (or both sides) of the envelope 100 at the printing position Incidentally, the pressure-contacting rollers 105a and 105b indicate rotating members of a type that sandwiches upper and lower faces of the envelope 100 to convey the same.

When the envelope 100 is conveyed to the printing position according to rotations of the pair of pressure-contacting rollers 105a and 105b in this manner for printing, there is such a problem that wrinkles G such as shown in FIG. 8 occur on the envelope 100, or since the envelope 100 moves irregularly without moving straightly, it becomes impossible to conduct printing at a regular printing position.

Causes of the wrinkles G or the irregular movement include air staying in the bag-shaped envelope 100. Accordingly, it is necessary to remove air in the envelope 100, and it is necessary to provide scores to the sheet member 100A securely when the first back pieces 102 and 103 are folded to a back side and bring the first back pieces 102 and 103 into close contact with the back face of the surface piece 101 in order to remove air in the envelope 100. Therefore, such a case that finishing of a folding work is manually performed occurs, which results in increase in cost of the envelope 100.

In view of these circumstances, a research about wrinkles occurring when printing on the envelope 100 is performed and a research for straight moving an envelope to perform collect printing have been conducted variously on the printing machine or the like side (for example, see JP-A-05-333737).

Patent Document 1: JP-A-05-333737

As shown in Patent Document 1, however, regarding a printing machine or the like that has been applied with a technique where wrinkles do not occur, occurrence of wrinkles can be prevented securely in printing using the printing machine or the like, but such a problem is not solved when the same envelope is printed by another printing machine or the like. Accordingly, in order to introduce a printing technique where wrinkles do not occur on an envelope, it is necessary to perform replacement of the printing machine or the like by another printing machine or the like, which results in such a problem that vast costs pile up.

Therefore, there is a technical problem to be solved for applying predetermined printing on an envelope without depending on a printing machine or the like to be used and without causing wrinkles on the envelope or making the printing position inaccurate, and an object of the present invention is to solve the problem.

SUMMARY OF THE INVENTION

The present invention has been proposed in order to achieve the above object, and the present invention described in claim 1 provides an envelope that is formed in a bag shape by closing a lower end and left and right side portions and providing an opening portion at an upper end, and providing a sealing portion for sealing the opening portion at an upper end of a back face side of the envelope, wherein an air relief hole for removing air in a bag is provided at a portion positioned at the upper end of the back face side of the envelope and sealed by the sealing portion.

According to the constitution, when an envelope inserted from a bottom side thereof into a printing machine or the like passes through between a pair of rotating upper and lower pressure-contacting rollers in the printing machine or the like, air staying in the bag is exhausted from the air relief hole so that a surface and a back face of the bag are brought into close contact with each other and the envelope is changed in one sheet shape. Thereby, forces applied on the surface and the back face of the envelope from the pressure-contacting rollers become approximately even as a whole, so that occurrence of wrinkles on the envelope is suppressed. Since air in the bag of the envelope is completely removed so that the envelope is changed in one sheet-like shape, the pair of upper and lower pressure-contacting rollers convey the envelope straightly while pressing the envelope with even pressing force in a rotating manner. The air relief hole is provided at a portion on the back face side which is covered with the sealing portion when the opening portion of the envelope is sealed by the sealing portion. Therefore, the air relief hole is prevented from being exposed in a usage state of the envelope, so that commodity value or appearance of the envelope is kept high at a use time of the envelop.

The invention described in claim 2 provides an envelope where a plurality of the air relief holes is formed along a longitudinal direction of the opening portion.

According to the constitution, the plurality of the air relief holes are provided along the longitudinal direction of the opening portion such that, even if air stays at any position in the bag of the envelope, air in the bag is completely removed by pressing the envelope evenly by the pair of upper and lower pressure-contacting rollers.

The invention described in claim 3 provides an envelope where the plurality of the air relief holes is each formed in a slit shape toward the opening portion.

According to the constitution, the air relief holes provided on the envelope is formed on the upper end portion on the back face of the envelope in an extremely narrow slit shape so as to extend toward the opening portion in order to make the air relief holes formed on the envelope inconspicuous. Therefore, air in the bag is exhausted effectively through the slits by continuously pressing the envelope from a lower portion of the envelope by the pair of upper and lower pressure-contacting rollers.

The invention described in claim 4 provides an envelope that is also formed with air relief holes on left and right side edge portions of the envelope in addition to the constitution of the air relief hole in each of the inventions described above.

According to the constitution, the air relief holes are provided on the upper portion of the back face near the opening portion of the envelope and they are also provided on both the left and right side edge portions of the envelope in order to further improve an effect of exhausting air staying in the bag of the envelope. Incidentally, the air relief holes provided on both the left and right side edge portions may be provided at any portions of the left and right edge portions one by one, or they may be provided along the left and right edge portions at any intervals in a plural manner.

EFFECT OF THE INVENTION

According to the envelope described in claim 1, the envelope can be straightly conveyed up to a printing position without depending on a printing machine or the like and without consistently generating wrinkles on the envelope. Thereby, poor printing due to occurrence of a wrinkle can be prevented and predetermined printing on an envelope at a predetermined position can be performed securely. By sealing an opening of an envelope at its use time, the air relief hole is necessarily concealed by the sealing portion, so that commodity value or appearance of the envelope is not degraded at a use time of the envelope.

According to the envelope described in claim 2, since the plurality of air relief holes are provided along the longitudinal direction of the opening portion of the envelope, such an effect can be achieved in addition to the effect of the envelope described in claim 1 that, even if air stays at any portion in the bag of the envelope, air in the bag can be removed by pressing the envelope evenly by the pair of upper and lower pressure-contacting rollers.

According to the envelope described in claim 3, since the air relief hole or holes are each formed in an extremely thin slit shape at the upper end portion of the back face side of the envelope, such an effect can be achieved in addition to the effects of the envelope described in claim 1 and 2 that the air relief hole or holes provided on the envelope are made inconspicuous. Therefore, commodity value of the envelope at a selling time is not prevented from be degraded.

According to the envelopes described in claim 4, since the air relief holes are formed at the side portions and the upper end portion of the envelope, such an effect can be achieved in addition to the effects of the envelope described in claim 1, 2 and 3 that air in the bag of the envelope can be removed further effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of an envelope according to a first embodiment of the present invention;

FIG. 2 is a development view of the envelope shown in FIG. 1;

FIG. 3 is a diagram showing a manufacturing process of the envelope shown in FIG. 1;

FIG. 4 is a plan view of an envelope according to a second embodiment of the present invention;

FIG. 5 is a development view of the envelope shown in FIG. 4;

FIG. 6 is a plan view of an envelope according to a third embodiment of the present invention;

FIG. 7 is a development view of the envelope shown in FIG. 6;

FIG. 8 is a plan view showing a conventional envelope; and

FIGS. 9A and 9B are a front view and a side view for explaining a printing process of an envelope.

BEST MODE FOR CARRYING OUT THE INVENTION

In a best mode for carrying out the invention, a plurality of air relief holes for removing air in a bag are provided on a portion which is positioned on a back face side of an envelope and where an opening portion is sealed by a sealing portion in order to achieve such an object that predetermined printing is performed on the envelope without depending on a printing machine or the like and without causing any wrinkle on the envelope and making printing inaccurate. Thereby, the envelope of the present invention is realized by causing the envelope to pass through between a pair of pressure-contacting rollers such that, when the envelope passes through between the pair of upper and lower pressure-contacting rollers rotating in a manner sandwiched therebetween, air staying in the bag of the envelope is removed from the air relief holes to the outside so that the envelope is changed in one sheet shape.

Specific embodiments of an envelope according to the invention will be explained below in detail with reference to the drawings. Incidentally, in the drawings used in respective embodiments described below, same constituent elements are attached with same numeral reference, and repetitive explanation thereof is omitted as much as possible.

First Embodiment

A first embodiment of the present invention will be explained in detail with reference to FIG. 1 to FIG. 3. FIG. 1 is a plan view of an envelope according to the first embodiment of the present invention, FIG. 2 is a development view of the envelope shown in FIG. 1, and FIG. 3 is a diagram showing a manufacturing process of the envelope shown in FIG. 1.

A structure and a manufacturing method of an envelope 10 shown in FIG. 1 will be explained also referring to a development view in FIG. 2 and a step diagram in FIG. 3. In a punching-out step processing, first, a sheet of paper is set in a press cutting machine (not shown), the paper is pressed by a press cutting machine, and an envelope sheet member 10A having a surface piece 11 with a sealing portion 11a, first back pieces 12 and 13 provided so as to continue into both left and right side edges of the surface piece 11, serving as overlap width pieces, and a second back piece 14 provided so as to continue into a lower end of the surface piece 11 is punched out. Incidentally, a size of the second back piece 14 is approximately the same size as the surface face 11 which does not include the sealing portion 11a. Scores 15, 15, 16, and 17 are respectively formed at boundary portions between the surface piece 11 and the first back pieces 12 and 13, a boundary portion between the surface piece 11 and the second back piece 14, and a boundary portion between the surface piece 11 and the sealing portion 11a at a forming time of the envelope sheet member 10A.

Many slit-like air relief holes 18 extending in a longitudinal direction are formed on a lower end portion of the second back piece 14 at equal intervals. Formation positions of the air relief holes 18 are set at such positions that all the slits are covered with the sealing portion 11a when an opening portion of the envelope 10 is sealed by the sealing portion 11a of the surface piece 11.

Incidentally, regarding the length or the interval of the slits serving as the air relief holes 18, any length and any interval can be adopted such that all the slit portions are covered with the sealing portion 11a when the opening portion of the envelope 10 is sealed by the sealing portion 11a. The intervals of the air relief holes 18 may not be equal necessarily. However, regarding the length, the width, the interval of the slits, and the like, they must be determined considering that air staying in a bag of the envelope 10 should be removed evenly.

The shape of the air relief hole 18 is not limited to a thin slit. For example, the air relief hole 18 may be formed as a circular hole with a diameter of about 1.0 to 3.0 millimeters, as a polygon with an inner maximum width of about 1.0 to 3.0 millimeters, as a cut line with a length of about 1.0 to 3.0 millimeters, or as a waveform cut line. Incidentally, the number, the size and shape, and the interval of air relief holes 18 may be determined properly for each envelope.

It is desirable that the air relief holes 18 formed simultaneously with press cutting for the envelope sheet member 10A are formed such that cutting is performed from a surface side of the envelope 10 toward a back side thereof by a cutter (not shown) and an appearance is saved such that burrs occurring at a forming time of the air relief holes 18 project toward inside of the envelope 10. However, since the air relief holes 18 are concealed by the sealing portion 11a when the opening portion of the envelope 10 is sealed by the sealing portion 11a, they may be formed such that cutting is performed from the back side of the envelope 10 toward the surface side thereof by the cutter. That is, in this case, burrs occurring at the forming time of the air relief holes 18 project toward the outside of the envelope 10, but since the air relief holes 18 are concealed by the seating portion 11a, an appearance can be finally saved as an envelope.

Then, the manufacturing process proceeds to a processing at a pasting step shown in FIG. 3. In the processing at the pasting step, first, the first back pieces 12 and 13 are folded to the back side along the scores 15 and 15. Subsequently, the second back piece 14 is folded to the back side along the score 16, so that the second back piece 14 is lapped on a back face of the surface piece 11 so as to cover the first back pieces 12 and 13 serving as the overlap widths. At this time, the first back pieces 12 and 13 and the second back piece 14 overlapping with each other are pasted to each other by such adhesive as glue. Thereby, a bag-shaped envelope 10 with the lower end and both the left and right side portions closed and an upper end opened is formed. FIG. 1 shows the envelope 10 thus formed, where many slit-like air relief holes 18 are arranged at a portion positioned at an upper end to be sealed by the sealing portion along a longitudinal direction of the opening portion in the envelope 10.

When printing is performed on the surface piece 11 (or the second back piece 14) of the envelope 10 thus formed, the envelope 10 is caused to pass through between a pressure-contacting rollers 105a and 105b of a pair of upper and lower rotating in a printing machine or the like from a side of the envelope 10 which does not include the sealing portion 11a (namely, a bottom side of the envelope 10) in a manner sandwiched and it is conveyed up to a printing position according to rotation of the pair of pressure-contacting rollers 105a and 105b so that predetermined printing can be conducted on a predetermined portion of the surface piece 11 or the back piece 14 of the envelope 10, for example, like the case explained with reference to FIG. 9.

In the case that the envelope 10 is used, when the envelop 10 passes through between the pair of upper and lower pressure-contacting rollers 105a and 105b in a state sandwiched from the above and the below, air staying in the bag is removed through the air relief holes 18 formed on the opening portion side of the envelope 10. Thereby, the first back piece 12 and 13 and the second back piece 14 are brought into close contact with each other, the envelope 10 is changed in one sheet shape, and forces of the pair of upper and lower pressure-contacting rollers 105a and 105b are applied to whole upper and lower faces of the envelope 10 evenly, so that occurrence of wrinkles on the envelope 10 is suppressed. The envelope 10 is moved straightly up to the printing position according to rotations of the pair of upper and lower pressure-contacting rollers 105a and 105b. As a result, predetermined printing is accurately performed on the predetermined position on a flat envelope face which does not include any wrinkle.

Second Embodiment

FIG. 4 and FIG. 5 show a second embodiment of the present invention, FIG. 4 is a plan view of an envelope according to the second embodiment of the present invention, and FIG. 5 is an development view of the envelope shown in FIG. 4. An envelope 20 according to the second embodiment is formed as an envelope 20 shown in FIG. 4 via a punching-out step processing and a pasting step processing like the case of the first embodiment. Accordingly, in explanation with same constituent portions as those of the envelope shown in FIG. 1 and FIG. 2 attached with same numeral reference, the envelope 20 of the second embodiment is formed in such a shape as shown by a development view in FIG. 5 by press-cutting a sheet of a paper in a press cutting machine in a punching-out processing step.

That is, as shown in FIG. 5, a sheet-like envelope sheet member 20A having a surface piece 21 with a sealing portion 21a, first back pieces 22 and 23 provided to continue into both left and right side edges of the surface piece 21, and a second back piece 24 provided to continue into a lower end of the surface piece 21 is punched out together with formation of scores 15, 15, 16, and 17 and a plurality of air relief holes 18. Incidentally, in the first embodiment, many air relief holes 18 are formed on the lower end portion of the back piece 14 in a slit shape along the longitudinal direction, as explained with reference to FIG. 2. In the second embodiment, however, many slits are formed on upper end portions of the first back pieces 22 and 23 along the longitudinal direction instead of the air relief holes 18 in the first embodiment. That is, in the second embodiment, the air relief holes 18 are formed in a slit shape at a portion where, when the opening portion of the envelope 20 is sealed by the sealing portion 21a, the first back pieces 22 and 23 are covered with the sealing portion 21a. Incidentally, the shape or the intervals of the air relief holes 18 are similar to those in the first embodiment.

In the next pasting step, first, the first back pieces 22 and 23 of the envelope sheet member 20A are folded to the back side along the scores 15 and 15, respectively, and distal end portions 22a and 23a of the first back pieces 22 and 23 that are superimposed on each other at a central portion are pasted to each other using adhesive. Subsequently, the second back piece 24 is folded to the back side along the score 16, it is lapped over the first back pieces 22 and 23, and the first back pieces 22 and 23 and the second back piece 24 are pasted to each other using adhesive. Thereby, the lower end and both the left and right side portions are closed, so that a bag-shaped envelope 20 with an opened upper end shown in FIG. 4 is finished.

Accordingly, when printing is performed on the surface piece 21 or the first back pieces 22 and 23 of the envelope 20 in the second embodiment formed such as shown in FIG. 4, the envelope 20 is caused to pass through between a pair of upper and lower pressure-contacting rollers rotating 105a and 105b in a printing machine or the like from a side of the envelope 20 which does not include the sealing portion 21a (namely, a bottom side of the envelope 20) in a manner sandwiched therebetween and it is conveyed up to a printing position according to rotation of the pair of pressure-contacting rollers 105a and 106 so that predetermined printing can be conducted on a predetermined portions of the surface piece 21 or the first back pieces 22 and 23 of the envelope 10, for example, like the case explained with reference to FIG. 9.

In the case that the envelope 20 is used, when the envelope 20 passes through between the pair of upper and lower pressure-contacting rollers 105a and 105b in a state sandwiched from the above and the below, air staying in the bag is removed through the air relief holes 18. Thereby, the surface piece 21 and the first back piece 22 and 23 are brought into close contact with each other, the envelope 20 is changed in one sheet shape, and forces of the pair of upper and lower pressure-contacting rollers 105a and 105b are applied to whole upper and lower faces of the envelope 20 evenly, so that occurrence of wrinkles on the envelope 20 is suppressed. The envelope 20 is moved straightly up to the printing position according to rotations of the pair of upper and lower pressure-contacting rollers 105a and 105b. As a result, predetermined printing is accurately performed on the predetermined portion on a flat envelope face which does not include any wrinkle.

Third Embodiment

FIG. 6 and FIG. 7 show a third embodiment of the present invention, FIG. 6 is a plan view of an envelope according to the third embodiment of the present invention, and FIG. 7 is an development view of the envelop shown in FIG. 6. An envelope 30 according to the third embodiment is formed as an envelope 30 shown in FIG. 6 via a punching-out step processing and a pasting step processing like the case of the first embodiment. Accordingly, in explanation with same constituent portions as those of the envelope shown in FIG. 1 and FIG. 2 attached with same numeral reference, the envelope 30 of the third embodiment is formed in such a shape as shown by a development view in FIG. 7 by press-cutting a sheet of a paper in a press cutting machine in a punching-out processing step.

That is, a sheet-like envelope sheet member 30A having a surface piece 31 with a sealing portion 31a, first back pieces 32 and 33 provided to continue into both left and right side edges of the surface piece 31, and a second back piece 34 provided to continue into a lower end of the surface piece 31 is punched out together with formation of scores 15, 15, 16, and 17 and a plurality of air relief holes 18.

Incidentally, in the first embodiment, many air relief holes 18 are formed on the lower end portion of the second back piece 14 in a slit shape along the longitudinal direction, as explained with reference to FIG. 2. In the third embodiment, however, many slits are formed on an upper end portion of the first back piece 33 along the longitudinal direction instead of the air relief holes 18. That is, in the third embodiment, the air relief holes 18 are formed in a slit shape at a portion where, when the opening portion of the envelope 30 is sealed by the sealing portion 31a, the first back piece 33 is covered with the sealing portion 31a. Incidentally, the shape or the intervals of the air relief holes 18 are similar to those in the first embodiment.

In the next pasting step, first, the first back pieces 32 and 33 of the envelope sheet member 30A are respectively folded to the back side along the scores 15 and 15, a distal end portion 33a of the first back piece 33 covering an approximately whole back face of the surface piece 31 is lapped over the first back piece 32 serving as an overlap width except for an engagement portion (the sealing portion) 31a, and the distal end portion 33a and the lapping portion are pasted to each other using adhesive. Subsequently, the second back piece 34 is folded to the back side along the score 16, and is lapped over the first back piece 33, and the first back piece 33 and the second back piece 34 are pasted to each other using adhesive. Thereby, the lower end and both the left and right side portions are closed, so that a bag-shaped envelope 30 with an opened upper end and shown in FIG. 6 is finished.

Accordingly, when printing is performed on the surface piece 31 or the first back piece 33 of the envelope 30 in the third embodiment thus formed, the envelope 30 is caused to pass through between a pair of rotating and upper and lower pressure-contacting rollers 105a and 105b in a printing machine or the like from a side of the envelope 30 which does not include the sealing portion 21a (namely, a bottom side of the envelope 20) in a manner sandwiched therebetween and it is conveyed up to a printing position according to rotation of the pair of pressure-contacting rollers 105a and 105b so that predetermined printing can be conducted on a predetermined portion of the surface piece 31 or the first back piece 33 of the envelope 30, for example, like the case explained with reference to FIG. 9.

In the case that the envelope 30 is used, when the envelope 30 passes through between the pair of upper and lower pressure-contacting rollers 105a and 105b in a state sandwiched from the above and the below, air staying in the bag is removed through the air relief holes 18. Thereby, the surface piece 31 and the first back piece 32 and 33 are brought into close contact with each other, the envelope 30 is changed in one sheet shape, and forces of the pair of upper and lower pressure-contacting rollers 105a and 105b are applied to whole upper and lower faces of the envelope 30 evenly, so that occurrence of wrinkles on the envelope 30 is suppressed. The envelope 30 is moved straightly up to the printing position according to rotations of the pair of upper and lower pressure-contacting rollers 105a and 105b. As a result, predetermined printing is accurately performed on the predetermined portion on a flat envelope face which does not include any wrinkle.

Further, the present invention provides an envelope formed with air relief holes at both left and right side edge portions of the envelope. For example, in the envelope sheet member 10A shown in FIG. 2, a plurality of air relief holes are provided along the score 15 between the surface piece 11 and the first back pieces 12 and 13. Accordingly, when both of these air relief holes and the air relief holes 18 provided on the upper end of the second back piece 14 described above are used, air in the envelope bag can be exhausted further effectively.

The present invention can be modified variously within the scope and spirit of the present invention and the present invention can be applied to a modified configuration, of course.

Claims

1. An envelope that is formed in a bag shape by closing a lower end and left and right side portions and providing an opening portion at an upper end, and providing a sealing portion for sealing the opening portion at an upper end of a back face side, wherein an air relief hole for removing air in a bag is provided at a portion positioned at the upper end of the back face side of the envelope and sealed by the sealing portion.

2. The envelope as claimed in claim 1, wherein a plurality of the air relief holes are formed along a longitudinal direction of the opening portion.

3. The envelope as claimed in claim 2, wherein the plurality of the air relief holes are each formed in a slit shape toward the opening portion.

4. The envelope as claimed in claim 1, 2, or 3, wherein the air relief holes are formed also on both left and right side edge portions of the envelope.