JP6570903B2 - Book protective cover, book to which the cover is attached, and method for manufacturing book with protective cover - Google Patents

Description

  The present invention relates to a book protective cover for protecting a book by covering the book with a laminated film including a heat-shrinkable film and a non-heat-shrinkable sheet, a book to which the cover is attached, and manufacture of the book with the protective cover. It is about the method.

  In recent years, book covers using shrink wrapping have been used particularly for comic books as a measure for preventing books from being read and stained.

  The shrink film used in the above shrink wrapping is usually transparent, so the cover, back, and back cover of the book can be seen at a glance even when the cover is put on. Can be guaranteed.

  Shrink wrapping for comic books puts the book in a cylindrical shrink film and heats the shrink film by heating the periphery of the book (front cover, back, back cover, small edge) with a heating gun. Adhere the shrink film to the book.

  Also, cover the cover part of the book with a shrink film, put it into a tabletop shrink wrapping machine, seal the shrink film corresponding to the upper and lower edges of the book, cut it, and shrink it with the heater provided inside There is also known an automatic shrink wrapping apparatus in which a film is thermally shrunk to be in close contact with a book (for example, Patent Document 1).

  The above-described shrink wrapping prevents the book from being opened by bringing a shrink film into close contact with the outer periphery (body portion) of the book.

Registered Utility Model No. 3067592

  However, the above-described conventional shrink packaging for books is effective for comic books that can be sold without opening the contents, but there is a problem that it cannot be applied to books such as utility books and picture books.

  In detail, people who want to purchase utility books often make sure that the necessary technical contents are published there, and cover the periphery of the book with a shrink film like a comic book. If you do, you will be shunned because you do not know the contents.

  In addition, as for picture books, since the decisive factor in purchase is how accurately the displayed creatures, rocks, vehicles, paintings, etc. are expressed, it will be avoided if the contents cannot be seen.

  For these reasons, books such as utility books and pictorial books are not covered, or when they are covered, the covers must be removed each time there is a request to view the contents.

  Also, assuming that the bookstore returns to the publisher, this kind of book, unlike the weekly magazine, has a long display period before the return, so if the book is displayed and returned without the cover, the publisher side Therefore, after replacing the cover and belt with a new one, a complicated work of reprinting to a required bookstore is required.

  The present invention has been made in consideration of the problems in the conventional book protection cover as described above, and can protect practical books, pictorial books, etc. that need to show the contents at low cost, and is always in a clean state. A book protection cover that can be arranged in a bookstore, a book to which the cover is attached, and a method for manufacturing the book with the protection cover are provided.

  The present invention is a book protective cover comprising a heat-shrinkable film and a non-heat-shrinkable sheet, wherein the book protective cover includes a cover cover portion that covers the cover of the book and a spine that covers the back of the book. A side cover part, a back cover cover part covering the back cover of the book, a front cover folded part folded back inside the front cover cover part, and a back cover folded part folded inside the back cover cover part The heat-shrinkable film and the non-heat-shrinkable sheet are bonded to each other in at least a part of the front cover cover portion, the back cover cover portion, the front cover turn-back portion, and the back cover turn-back portion. It is the book protective cover characterized by being made.

  In this invention, it is preferable that the said heat-shrinkable film and the said non-heat-shrinkable sheet | seat are adhere | attached in a part of said back side cover part.

  In the present invention, the heat-shrinkable film is preferably a polyester film.

  In the present invention, it is preferable that the book protection cover is formed in a bag shape at the front cover folding portion and the back cover folding portion.

  Moreover, this invention also includes the book to which the book protection cover which has the said structure was attached.

  Furthermore, this invention is a manufacturing method of the book with a protective cover, Comprising: The manufacturing method of the book with a protective cover which has the process of attaching the book protective cover which has the said structure to a book, and the process of heat-shrinking the said book protective cover. Is also included.

  According to the book protection cover of the present invention, the contents of the book can be viewed even when attached to the book, and the book can be protected at a low cost.

  According to the book to which the book protection cover according to the present invention is attached, it is only necessary to replace the book protection cover when returned, and there is an advantage that it is not necessary for the publisher to replace the cover and the belt with a new one. .

  According to the method for producing a book with a protective cover of the present invention, the book can be packaged with the book protective cover by a simple method.

It is the perspective view which showed the book protection cover which concerns on this invention. It is the top view which showed the book protective cover which concerns on this invention of the state before performing heat sealing. It is the top view which showed the book protection cover of different embodiment which concerns on this invention of the state before performing heat sealing. It is a perspective view which shows the state which attached the book protection cover which concerns on this invention to the book.

  Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.

  FIG. 1 is a perspective view showing a book protection cover (hereinafter abbreviated as a protection cover) according to the present invention, and shows a state before the book is covered.

  The protective cover 1 is a laminated film including a heat-shrinkable film and a non-heat-shrinkable sheet. The protective cover 1 includes a front cover cover portion 2 that covers the front cover of the book, a back cover portion 3 that covers the back portion of the book, a back cover cover portion 4 that covers the back cover of the book, and the inside of the cover cover portion 2. A front cover folding part 5 folded back and a back cover folding part 6 folded inside the back cover cover part 4. In the present specification, the book is not particularly limited as long as it has a front cover, a back, and a back cover, and includes not only a book but also a notebook, a notebook, an album, and the like.

  The protective cover 1 includes a portion that is folded inside the front cover cover portion 2 (front cover folding portion 5) and a portion that is folded inside the back cover cover portion 4 (back cover folding portion 6). In FIG. Specifically, the cover cover folding part 5 is bonded to the top edge of the cover cover folding part 5 and the top edge of the cover cover cover part 2 by heat sealing (the part marked with symbol x in FIG. 1), and The lower edge of the front cover folding part 5 and the lower edge of the front cover cover part 2 are bonded together, and the back cover folding part 6 is also heat-sealed so that the upper edge of the back cover folding part 6 and the back cover cover part 4 The upper edge is bonded, and the lower edge of the back cover folding portion 6 and the lower edge of the back cover cover portion 4 are bonded.

  FIG. 2 shows a plan view of the protective cover according to the present invention before the heat sealing. In the protective cover 1, the heat-shrinkable film and the non-heat-shrinkable sheet are adhered to at least a part of the front cover cover portion 2, back cover cover portion 4, front cover turnback portion 5, and back cover turnback portion 6. (Grey portions (a1, a2) in FIG. 2). If the protective cover 1 can be brought into close contact with the book without causing wrinkles or tarmi on the protective cover 1 or warping of the front cover or back cover of the book, other than the back cover 3 Even if the heat-shrinkable film and the non-heat-shrinkable sheet are not bonded to each other in some regions (the front cover cover portion 2, the back cover cover portion 4, the front cover turn-back portion 5, and the back cover turn-back portion 6). I do not care. For example, in some areas in the vicinity of the back cover 3 of the front cover cover 2 and in some areas in the vicinity of the back cover 3 of the back cover 4, the heat-shrinkable film and the non-heat-shrinkable sheet It does not matter if it is not bonded. The heat-shrinkable film and the non-heat-shrinkable sheet may be bonded to each other at 70% or more of the total area of the front cover cover portion 2, the back cover cover portion 4, the front cover turn-back portion 5, and the back cover turn-back portion 6. Preferably, 80% or more, more preferably 90% or more, most preferably 100% (except for the back cover portion 3, the heat-shrinkable film and the non-heat-shrinkable sheet are bonded, The heat-shrinkable film and the non-heat-shrinkable sheet are adhered to all regions of the front cover cover portion 2, the back cover cover portion 4, the front cover turn-back portion 5, and the back cover turn-back portion 6. The dimensions of each part of the protective cover according to the present invention before and after heat shrinkage, details of the heat shrinkable film and the non-heat shrinkable sheet will be described later.

  As for the back cover part 3, even if the heat-shrinkable film and the non-heat-shrinkable sheet are not bonded, the heat-shrinkable film and the non-heat-shrinkable sheet may be partially bonded. For example, in some areas in the vicinity of the front cover cover part 2 of the back cover part 3 and in some areas in the vicinity of the back cover cover part 4 of the back cover part 3, the heat shrinkable film and the non-heat shrinkable sheet As shown in FIG. 3, the heat-shrinkable film and the non-heat-shrinkable sheet may be adhered in a stripe shape (a3 in FIG. 3) in the back cover portion 3. It is preferable that the heat-shrinkable film and the non-heat-shrinkable sheet are bonded to each other at an area of 50% or less of the back cover portion 3, more preferably 30% or less, still more preferably 20% or less, and most preferably 10 % Or less. In FIG. 2, the heat-shrinkable film and the non-heat-shrinkable sheet are not bonded to each other in the back-side cover portion 3, and the heat-shrinkable film and the non-heat-resistant material are covered in all regions except for the back-side cover portion 3. The protective cover 1 is bonded to the shrinkable sheet.

  The protective cover 1 is attached to the book, and then the protective cover 1 is thermally shrunk to produce a book with a protective cover.

  FIG. 4 is a perspective view showing a state in which the protective cover 1 is in close contact with the book 7 to be packaged by thermally shrinking the protective cover 1. In addition, the code | symbol 7a in the book 7 has shown the front cover, 7b the back part, 7c has shown the back cover, and 7d has shown the fore edge. Further, 8 is a book cover attached to the book 7, 8a is a front cover cover look-back, 8b is a back cover cover look-back, and 9 is a belt.

  The protective cover 1 and the book 7 are put into a book packing shrink device (not shown). This shrink device is configured to perform a process of attaching the protective cover 1 to the book 7 and a process of thermally shrinking the protective cover 1 with a heater over time.

  By the heat shrinking step, the back cover portion 3 in which the non-heat shrinkable sheet is not bonded to the heat shrinkable film is heat shrunk. As a result, the protective cover 1 is in close contact with the front cover 7a and the back cover 7c of the book 7, but the fore edge 7d is not subject to packaging, so the contents of the book can be viewed freely even after shrink packaging. Can do.

  Since the book 7 is usually provided with a book cover 8 and a band 9, the protective cover 1 is packaged together with the cover.

  In addition, the protective cover 1 may be provided with a notch in the back side cover portion 3, for example, or may be perforated in the vertical direction so that it can be easily removed.

  The protective cover 1 can be printed with characters and logos of store names, coloring and designs for decoration, symbols for classification, and the like.

[Dimensions of each part of protective cover before heat shrink]
When the thickness of the book to be packaged is T, the lateral length t ′ of the portion of the protective cover 1 where the non-heat-shrinkable sheet is not adhered to the heat-shrinkable film is preferably 1.1T to 4T. When the protective cover 1 is heat shrunk, the protective cover 1 comes into close contact with the book. However, when the horizontal length t ′ of the protective cover 1 is within the above range, the heat shrink is performed between the book and the protective cover 1. The protective cover 1 can be brought into close contact with the book without causing slack, wrinkles or tarmi on the protective cover 1 that is in close contact with the book, or warping of the cover of the book. If t ′ is less than 1.1T, the cover of the book may be warped after heat shrinkage. If t ′ exceeds 4T, the book cover and the protection cover 1 may be damaged even if the protection cover 1 is subjected to heat shrinkage. There is a possibility that the protective cover 1 cannot be brought into close contact with the book due to looseness between them or wrinkles or tarmi generated on the protective cover 1 brought into close contact with the book.

  When the cover width of the book to be packaged (the total length of the front cover, back, and back cover of the book) is L, the front cover cover 2, the back cover 3, and the back cover of the protective cover 1 The total lateral width of the portion 4 (hereinafter referred to as the lateral width l ′) is preferably 1.01L to 1.2L. When the horizontal width l ′ is within the above range, the protective cover 1 can be easily attached to the book because the length of the horizontal width l ′ is larger than the length of the cover width L of the book. The lateral width l ′ can be easily adjusted by changing the lateral length w3 of the front cover folding portion 5 and the lateral length w4 of the back cover folding portion 6.

  When the vertical length of the book to be packaged is H, the vertical length h ′ of the protective cover 1 is preferably 1.01H to 1.15H. When the lateral length of the book to be packaged is W, the lateral length w1 of the area where the heat shrinkable film and the non-heat shrinkable sheet are bonded is 1.01 W, which corresponds to the whole or most of the front cover cover 2. The lateral length w2 of the region where the heat-shrinkable film and the non-heat-shrinkable sheet are bonded, which corresponds to the whole or most of the back cover cover portion 4, is preferably 1.01W to 1.15W. It is preferable that it is 15W. The lateral length w3 of the front cover folded portion 5 is preferably 0.2 W to 0.7 W, and the lateral length w4 of the back cover folded portion 6 is also preferably 0.2 W to 0.7 W.

[Dimensions of each part of protective cover after heat shrink]
The lateral length T ′ after heat shrinkage of the portion of the protective cover 1 where the heat shrinkable film and the non-heat shrinkable sheet are not bonded is preferably 1.01T to 2T. When the horizontal length T ′ is within the above range, loosening occurs between the book and the protective cover 1, wrinkles and tarmi occur on the protective cover 1 in close contact with the book, and warping occurs on the cover of the book. The protective cover 1 can be brought into close contact with the book without doing so.

  The total width (hereinafter referred to as the width L ′) of the protective cover 1 after the heat shrinkage of the front cover portion 2, the back cover portion 3 and the back cover portion 4 is 1.01L to 1.2L. Is preferred. When the width L ′ of the protective cover 1 is within the above range, loosening occurs between the book and the protective cover 1, wrinkles and tarmi occur on the protective cover 1 that is in close contact with the book, and the cover of the book The protective cover 1 can be brought into close contact with the book without warping.

  Since the horizontal length w1, the horizontal length w2, the horizontal length w3, and the horizontal length w4 of the protective cover 1 are all the dimensions of the region where the heat-shrinkable film and the non-heat-shrinkable sheet are adhered, The dimensions hardly change. In addition, the horizontal length of the area | region where the heat-shrinkable film and the non-heat-shrinkable sheet | seat which correspond to the whole or most of the front cover cover part 2 after heat shrink, the whole back cover cover part 4 after heat shrink Or, the horizontal length of the region where the heat-shrinkable film and the non-heat-shrinkable sheet are bonded to each other, the horizontal length of the front cover folded portion 5 after heat shrinkage, the horizontal length of the back cover folded portion 6 after heat shrinkage These are expressed in order as W1, W2, W3, and W4. Similarly, the length H ′ of the protective cover 1 after heat shrinkage is almost the same before and after heat shrinkage, and the length H ′ is substantially the same as the length h ′ of the protective cover 1 before heat shrinkage. It is. The longitudinal length H ′ of the protective cover 1 is preferably 1.01H to 1.15H, the lateral lengths W1 and W2 are preferably 1.01W to 1.15W, and the lateral lengths W3 and W4 are 0.2W. It is preferable that it is -0.7W.

[Heat shrinkable film]
The heat-shrinkable film is not particularly limited, and a known film can be used, and examples thereof include a polyester film, a polyolefin film, a polystyrene film, a polyvinyl chloride film, and the like. preferable. Details of the polyester film (hereinafter referred to as heat-shrinkable polyester film) will be described later.

(Physical properties of heat-shrinkable film)
When the heat-shrinkable film used in the present invention is treated in warm water at 90 ° C. for 10 seconds in a no-load state, the length direction of the film (mainly calculated from the length before and after shrinkage by the following formula) The thermal contraction rate in the shrinking direction) is preferably 10% or more and 60% or less, more preferably 20% or more and 55% or less, and more preferably 30% or more and 50% or less. If the thermal shrinkage in the longitudinal direction at 90 ° C. is less than 10%, the shrinkage amount is too small, so that looseness occurs between the book and the protective cover 1, or wrinkles and On the other hand, when the thermal contraction rate in the longitudinal direction at 90 ° C. exceeds 60%, warpage may occur on the front cover and back cover of the book that has been covered after the thermal contraction. The heat shrinkage rate in the width direction of the heat-shrinkable film is preferably less than 30%, more preferably 15% or less. When the protective cover is attached to the book, it is preferably attached so that the width direction of the film is the longitudinal direction of the book.

The thermal shrinkage at 90 ° C. is measured as follows. First, the film was cut into a 10 cm × 10 cm square, heat-shrinked at 90 ° C. ± 0.5 ° C. in warm water for 10 seconds under no load condition, and then the longitudinal and width dimensions of the film were measured. Measure and use the following formula to determine the thermal shrinkage in the longitudinal and width directions.
Thermal shrinkage rate = {(length before shrinkage−length after shrinkage) / length before shrinkage} × 100 (%)

  The thickness of the heat-shrinkable film is not particularly limited, is preferably 5 μm or more, more preferably 10 μm or more, preferably 60 μm or less, more preferably 50 μm or less, and further preferably 40 μm or less. If the heat-shrinkable film is too thin, it is easy to tear, and if it is too thick, the shrinkage stress of the heat-shrinkable film becomes large, and there is a possibility that the cover of the book covered with the cover is warped after the heat shrinkage.

  It is preferable that the heat-shrinkable film is only one layer. However, if the protective cover 1 can be adhered closely to a book without generating wrinkles or tarmi, a heat-shrinkable film having a plurality of layers is used. The protective cover 1 provided may be used.

<Heat-shrinkable polyester film>
(Configuration of heat-shrinkable polyester film)
The heat-shrinkable polyester film preferably used in the present invention is preferably composed of ethylene terephthalate as a main constituent unit. “Main” means that all the structural units of polyester are 100 mol%, and ethylene terephthalate unit is preferably contained in an amount of 50 mol% or more, more preferably 55 mol% or more, and further preferably 60 mol% or more. When the content of the ethylene terephthalate unit is less than 50 mol%, the heat resistance and impact resistance of the resulting protective cover may be insufficient. In the present specification, “unit” refers to a repeating unit constituting a polymer derived from one polyhydric alcohol molecule and one polycarboxylic acid molecule, and in the case of ε-caprolactone, A structural unit obtained by opening a lactone ring is shown.

  This polyester preferably contains a unit derived from a polyhydric alcohol other than ethylene glycol and / or a unit derived from a polyvalent carboxylic acid other than terephthalic acid. Units derived from polyhydric alcohols other than ethylene glycol are ester units composed of terephthalic acid and polyhydric alcohols other than ethylene glycol. Units derived from polycarboxylic acids other than terephthalic acid are ethylene glycol and terephthalic acid. It is an ester unit consisting of a polyvalent carboxylic acid other than.

  Polyhydric alcohols other than ethylene glycol include propylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 2- Aliphatic diols such as methyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 1,9-nonanediol, and 1,10-decanediol; 1,4-cyclohexanedimethanol, 1 Alicyclic diols such as 1,4-cyclohexanediethanol; aliphatic polyhydric alcohols such as trimethylolpropane and pentaerythritol;

  Examples of the polyvalent carboxylic acid other than terephthalic acid include isophthalic acid, naphthalene-1,4- or -2,6-dicarboxylic acid, 5-sodium sulfoisophthalic acid, 4,4′-diphenyldicarboxylic acid, and diphenyl. Aromatic dicarboxylic acids such as sulfodicarboxylic acids; glutaric acid, adipic acid, sebacic acid, azelaic acid, oxalic acid, succinic acid, etc., and aliphatic dicarboxylic acids usually called dimer acids; trimellitic acid, pyromellitic acid and Aromatic polyvalent carboxylic acids such as acid anhydrides thereof; and the like.

  The total amount of units derived from a polyhydric alcohol other than ethylene glycol and units derived from a polyvalent carboxylic acid other than terephthalic acid is preferably 10 mol% or more, and 13 mol% or more in 100 mol% of all the constituent units. It is more preferable that A unit derived from a polyhydric alcohol other than ethylene glycol and / or a unit derived from a polyvalent carboxylic acid other than terephthalic acid can be an amorphous component. In the present invention, from the viewpoint of the shrink finish of the protective cover and the like, it is preferable that an amorphous unit is contained in the polyester constituent unit (the crystallinity of the heat-shrinkable polyester film is not 100%). For that purpose, it is preferable to use diethylene glycol, neopentyl glycol, or 1,4-cyclohexanedimethanol as the polyhydric alcohol, and it is more preferable to use at least one of neopentyl glycol and 1,4-cyclohexanedimethanol. .

  As an amorphous unit, for example, a monomer unit composed of isophthalic acid and ethylene glycol, a monomer unit composed of terephthalic acid and neopentyl glycol, a monomer unit composed of terephthalic acid and 1,4-cyclohexanedimethanol, and from isophthalic acid and butanediol And a monomer unit.

  The total amount of units derived from polyhydric alcohols other than ethylene glycol and units derived from polyvalent carboxylic acids other than terephthalic acid is preferably 30 mol% or less in 100 mol% of all the constituent units, % Or less is more preferable. If the total amount of units derived from a polyhydric alcohol other than ethylene glycol and units derived from a polyvalent carboxylic acid other than terephthalic acid exceeds 30 mol%, the heat resistance and impact resistance of the resulting film may be insufficient. If the film's solvent resistance is reduced and characters are printed on the protective cover, the ink's solvent (ethyl acetate, etc.) may cause whitening of the film in the printing process, or the film's tear resistance may be reduced. There is a risk.

  Here, the interpretation of the term “can be an amorphous component” will be described in detail.

  In the present invention, the “amorphous polymer” composed of amorphous units specifically refers to a polymer that does not have an endothermic peak due to melting as measured by a DSC differential scanning calorimeter. Amorphous polymers are substantially not crystallized and cannot be in a crystalline state, or have a very low crystallinity even when crystallized.

  In the present invention, the “crystalline polymer” composed of crystal units is not the above “amorphous polymer”, that is, a polymer having an endothermic peak due to melting as measured by a DSC differential scanning calorimeter. A crystalline polymer is one that can be crystallized at elevated temperatures, has a crystallizable property, or has already been crystallized.

  In general, for polymers in which many monomer units are bonded, the stereoregularity of the polymer is low, the target property of the polymer is poor, the polymer has a large side chain, the polymer has many branches, and the intermolecular molecules In the case of having various conditions such as a small cohesive force, an amorphous polymer is obtained. However, depending on the state of presence, crystallization may proceed sufficiently to become a crystalline polymer. For example, even if the polymer has a large side chain, crystallization can proceed sufficiently and become crystalline when the polymer is composed of a single monomer unit. Therefore, even if a polymer is produced using the same monomer unit, it may be a crystalline polymer or an amorphous polymer, so in the present invention, the expression “can be an amorphous component” Is used.

  In order to improve the slipperiness of the film, it is also preferable to include fine particles such as an organic lubricant and an inorganic lubricant. If necessary, it may contain additives such as a stabilizer, a colorant, an antioxidant, and an antifoaming agent. Fine particles imparting slipperiness include known inactive external particles such as kaolin, clay, calcium carbonate, silicon oxide, calcium terephthalate, aluminum oxide, titanium oxide, calcium phosphate, lithium fluoride, and polyester film Examples thereof include insoluble high-melting-point organic compounds, cross-linked polymers, and metal compound catalysts used at the time of polyester synthesis, for example, internal particles formed inside the polymer during the production of the polyester by alkali metal compounds, alkaline earth metal compounds and the like. The fine particles are preferably 0.005 to 0.9% by mass in the film, and the average particle size is preferably 0.001 to 3.5 μm.

  Commercially available products may be used as the heat-shrinkable polyester film, and examples of the commercially available products include Daiwa Bell Fine (registered trademark) HS202 manufactured by Daiwa Steel Co., Ltd.

(Method for producing heat-shrinkable polyester film)
The heat-shrinkable polyester film is obtained by melt-extruding the above-described polyester raw material with an extruder to form an unstretched film, and uniaxially or biaxially stretching the unstretched film by a predetermined method shown below. Can do. The polyester can be obtained by polycondensing the above-described preferred dicarboxylic acid component and polyhydric alcohol component by a known method. Moreover, 2 or more types of chip-like polyester can be mixed and used as a raw material of a film.

  When the raw material resin is melt-extruded, the polyester raw material is preferably dried using a dryer such as a hopper dryer or a paddle dryer, or a vacuum dryer. After the polyester raw material is dried in such a manner, it is melted at a temperature of 200 to 300 ° C. and extruded into a film using an extruder. In extruding, any existing method such as a T-die method or a tubular method can be employed.

  And an unstretched film can be obtained by rapidly cooling the sheet-like molten resin after extrusion. In addition, as a method of rapidly cooling the molten resin, a method of obtaining a substantially unoriented resin sheet by casting the molten resin from a die onto a rotating drum and rapidly solidifying it can be suitably employed.

  In order to achieve the object of the present invention, the main shrinkage direction of the film may be either the film longitudinal (longitudinal) direction or the transverse (width) direction, or the longitudinal and transverse balance shrinkage type. In the following, the horizontal stretching-longitudinal stretching method in which the transverse stretching is performed first and then the longitudinal stretching will be described. .

  First, stretching in the transverse direction is performed. Stretching in the transverse direction is preferably performed at 65 ° C. to 85 ° C. for about 3.5 to 5 times in a state where both ends in the width direction of the film are held by clips in the tenter (first tenter). Prior to stretching in the transverse direction, preheating is preferably performed, and the preheating is preferably performed until the film surface temperature reaches 70 ° C to 100 ° C.

  After transverse stretching, the film is preferably passed through an intermediate zone where no aggressive heating operation is performed. If there is a temperature difference between the transverse stretching zone of the first tenter and the intermediate heat treatment zone, the heat of the intermediate heat treatment zone (hot air itself or radiant heat) flows into the transverse stretching process, and the temperature of the transverse stretching zone is not stable, so the film quality is stable. Therefore, it is preferable to carry out the intermediate heat treatment after passing the film after the transverse stretching and before the intermediate heat treatment through the intermediate zone over a predetermined time. In this intermediate zone, when a strip-shaped paper piece is hung in a state where the film is not passed through, the accompanying flow accompanying the running of the film, the transverse stretching zone and the middle so that the paper piece hangs almost completely in the vertical direction. When hot air from the heat treatment zone is shut off, a stable quality film can be obtained. A transit time of about 1 second to 5 seconds is sufficient for the intermediate zone. If it is shorter than 1 second, the length of the intermediate zone becomes insufficient, and the heat shielding effect is insufficient. In addition, the intermediate zone is preferably long, but if it is too long, the facility becomes large, so about 5 seconds is sufficient.

  After passing through the intermediate zone, it does not matter whether the intermediate heat treatment before longitudinal stretching is performed or not. However, when the temperature of the intermediate heat treatment after transverse stretching is increased, the molecular orientation that contributes to the foldability of the protective cover is relaxed and crystallization proceeds, so that the foldability of the protective cover is slightly deteriorated. In addition, the thickness spot becomes large. From this viewpoint, the intermediate heat treatment is preferably performed at 140 ° C. or lower. Further, the passage time of the intermediate heat treatment zone is preferably 20 seconds or less. A longer intermediate heat treatment zone is preferred, but about 20 seconds is sufficient. Thereby, a lateral uniaxially stretched film is obtained.

  In the present invention, the longitudinal stretching may or may not be performed subsequently, but it is preferable to perform the stretching because the tensile fracture strength of the film is improved. Therefore, the laterally uniaxially stretched film may be introduced into a longitudinal stretching machine in which a plurality of roll groups are continuously arranged. In longitudinal stretching, preheating is preferably performed with a preheating roll until the film temperature reaches 65 ° C to 110 ° C. When the film temperature is lower than 65 ° C., it becomes difficult to stretch the film in the longitudinal direction (that is, breakage tends to occur), which is not preferable. On the other hand, when the film temperature is higher than 110 ° C., the film tends to adhere to the roll, and the roll is not easily soiled by continuous production.

  When the temperature of the film falls within the above range, longitudinal stretching is performed. The longitudinal draw ratio differs depending on whether the main shrinkage direction is the longitudinal direction or the transverse direction. From the viewpoint of improving the tensile fracture strength, when the main shrinkage direction is the longitudinal direction, the longitudinal stretching ratio is preferably 2 to 5 times. On the other hand, from the viewpoint of improving the tensile fracture strength, when the main shrinkage direction is the transverse direction, the longitudinal draw ratio is preferably 1.2 to 1.8 times.

  After the longitudinal stretching, the film is preferably once cooled, and preferably cooled with a cooling roll having a surface temperature of 20 to 40 ° C. before the final heat treatment. The rapid cooling after the longitudinal stretching is preferable because the molecular orientation of the film is stabilized and the natural shrinkage of the film after becoming a product is reduced.

  Next, the film after longitudinal stretching and cooling is introduced into a second tenter for heat treatment, and heat treatment is performed. The heat treatment temperature is preferably 65 ° C to 100 ° C. If the heat treatment temperature is lower than 65 ° C., the heat treatment does not make sense. On the other hand, if the heat treatment temperature is higher than 100 ° C., the thermal shrinkage rate may be reduced. The heat treatment temperature is more preferably 70 to 95 ° C, and further preferably 75 to 90 ° C.

  Thereafter, the film roll of the heat-shrinkable polyester film used in the present invention can be obtained by winding the film while cutting and removing both ends.

[Non-heat-shrinkable sheet]
The non-heat-shrinkable sheet is not particularly limited as long as it is a sheet having low heat-shrinkability. For example, a non-heat-shrinkable film, paper, nonwoven fabric, etc. can be used, and a non-heat-shrinkable film is preferable.

  As a method for adhering the non-heat-shrinkable sheet to the heat-shrinkable film, a known method can be used. Adhesion using an adhesive such as a dry laminate adhesive / hot melt adhesive, thermal fusion of the sheet itself, Various means such as high-frequency fusion, ultrasonic fusion, and sewing such as sewing can be appropriately selected depending on the material of the non-shrinkable sheet.

<Non-heat-shrinkable film>
The non-heat-shrinkable film is not particularly limited, and a known film can be used, and examples thereof include a polyester film, a polyolefin film, a polystyrene film, a polyvinyl chloride film, and the like. (Hereinafter referred to as non-heat-shrinkable polyester film) or polyolefin film (especially polyethylene film, polypropylene film) is preferable.

  The non-heat-shrinkable polyester film can be produced in the same manner as the heat-shrinkable polyester film, and a known method can be used. The difference between the non-heat-shrinkable polyester film and the heat-shrinkable polyester film is that the heat shrinkage rate is different. For example, when producing a polyester film, the heat treatment temperature is compared with about 105 to 150 ° C. It is possible to produce a non-heat-shrinkable polyester film by appropriately setting production conditions and the like, for example, by setting it as high as possible. The heat treatment temperature is more preferably 120 to 140 ° C.

  Commercially available products may be used as the non-heat-shrinkable film. Examples of the commercially available products include Lix (registered trademark) films L6101 and L4102 manufactured by Film Toyobo Co., Ltd. as a polyethylene film, and Toyobo Co., Ltd. as a polyethylene terephthalate film. As a Toyobo Ester (registered trademark) film E5102, an OPP (biaxially stretched polypropylene) film, Toyobo Pyrene (registered trademark) film P2161, and as a CPP (unstretched polypropylene) film, Toyobo Pyrene (registered trademark) film P1128 Examples of the ONY (biaxially oriented polyamide) film include Harden (registered trademark) film N1102 manufactured by Toyobo Co., Ltd. Moreover, as a non-heat-shrinkable film, you may use the commercial item by which the heat-seal layer was laminated | stacked on the polyester-type film, and as a said commercial item, for example, a heat-seal layer is added to a non-heat-shrinkable polyester-type film. Examples thereof include Toyobo Ester (registered trademark) E7700 manufactured by Toyobo Co., Ltd. and Mylar (registered trademark) 850 manufactured by Teijin DuPont Films.

(Physical properties of non-heat-shrinkable sheet)
When the non-heat-shrinkable sheet used in the present invention is processed in warm water at 90 ° C. for 10 seconds in a no-load state, the longitudinal direction of the film calculated by the above formula from the length before and after shrinkage ( The heat shrinkage ratio in the main shrinkage direction) is preferably 3% or less, more preferably 1% or less, and further preferably 0.5% or less. Further, the heat shrinkage rate in the width direction of the non-heat-shrinkable sheet is preferably 3% or less, more preferably 1% or less, and further preferably 0.5% or less.

  The thickness of the non-heat-shrinkable sheet is preferably 10 μm or more, more preferably 30 μm or more, further preferably 50 μm or more, preferably 100 μm or less, and more preferably 80 μm or less.

  It is preferable that the non-heat-shrinkable sheet is only one layer, but if it is a protective cover 1 that can be closely adhered to a book without generation of wrinkles, tarmi, etc., a non-heat-shrinkable sheet having a plurality of layers. The protective cover 1 provided with a sheet may be used.

[Others]
Moreover, the ultraviolet absorber may be contained in at least one layer of the protective cover 1, and it is preferable that the protective cover 1 has a transmittance of light having a wavelength of 300 nm to 375 nm of 50% or less. By using the protective cover 1 containing an ultraviolet absorber, it is possible to prevent the book from being discolored (yellowed) by ultraviolet rays over time.

(90 ° C heat shrinkage of the film)
The film is cut into a 10 cm × 10 cm square, heat-shrinked at 90 ° C. ± 0.5 ° C. in warm water for 10 seconds under no load condition, and then measured in the longitudinal and width dimensions of the film. The thermal shrinkage rate in the longitudinal direction and the width direction is obtained using the following formula.
Thermal shrinkage rate = {(length before shrinkage−length after shrinkage) / length before shrinkage} × 100 (%)

(Film of heat-shrinkable polyester film F)
Polyesters A to D are polyesters obtained by reacting the acid component and polyhydric alcohol component shown in Table 1 below by a known method, and the lubricant contained in the polyester D is silicia (manufactured by Fuji Silysia Co., Ltd.). Registered trademark) 266. A heat-shrinkable polyester film F was produced using the polyesters A to D. The method for forming the heat-shrinkable polyester film F will be described below.

  The polyesters A to D were mixed at a mass ratio of 5: 66: 24: 5 and charged into an extruder. Thereafter, the mixed resin was melted at 280 ° C., extruded from a T die, wound around a rotating metal roll cooled to a surface temperature of 30 ° C., and rapidly cooled to obtain an unstretched film having a thickness of 240 μm. At this time, the take-up speed of the unstretched film (the rotation speed of the metal roll) was about 20 m / min. Thereafter, the unstretched film was guided to a tenter (first tenter) in which a transverse stretching zone, an intermediate zone, and an intermediate heat treatment zone were continuously provided. In the intermediate zone, when the strip-shaped paper piece is hung in a state where the film is not passed through, the hot air from the transverse stretching zone and the intermediate heat treatment zone are so arranged that the paper piece hangs almost completely in the vertical direction. Hot air is blocked.

  And after preheating the unstretched film led to the tenter until the film temperature reaches 80 ° C., the film is stretched 4 times at 70 ° C. in the transverse direction in the transverse stretching zone, and passed through the intermediate zone (pass Time = about 1.2 seconds), the film was led to an intermediate heat treatment zone and heat treated at 80 ° C. for 8 seconds to obtain a laterally uniaxially stretched film having a thickness of 36 μm.

  Further, the laterally stretched film was guided to a longitudinal stretching machine in which a plurality of roll groups were continuously arranged, preheated on a preheating roll until the film temperature reached 70 ° C., and then stretched 3 times. Thereafter, the longitudinally stretched film was forcibly cooled by a cooling roll set at a surface temperature of 25 ° C.

  Then, the film after cooling is guided to a tenter (second tenter), heat-treated in an atmosphere of 90 ° C. for 10 seconds in the second tenter, cooled, and both edges are cut and removed, whereby the thickness is reduced. A heat-shrinkable polyester film F was obtained by continuously forming a biaxially stretched film of about 13 μm over a predetermined length.

  The resin composition forming the film F is made of a polyester resin. In film F, the total amount of units derived from a polyhydric alcohol other than ethylene glycol and units derived from a polyvalent carboxylic acid other than terephthalic acid is 20 mol% in 100 mol% of all the constituent units, and neopentyl glycol and Since diethylene glycol is contained, the film F contains an amorphous component. The film F has a 90 ° C. heat shrinkage rate of 40% in the vertical direction and 10% in the horizontal direction.

(Non-heat shrinkable film)
As the non-heat-shrinkable film, a commercially available 60 μm Toyobo Lix (registered trademark) film L6101 was used. L6101 manufactured by Toyobo Co., Ltd. is a film mainly made of linear low density polyethylene (LLDPE). The 90 ° C. heat shrinkage ratio of L6101 manufactured by Toyobo Co., Ltd. is 0.3% in the vertical direction and 0.4% in the horizontal direction. .

(Comparative Example 1)
A book having a length of 148 mm, a width of 105 mm, and a thickness of 14 mm was prepared as a book to be packaged. The heat-shrinkable polyester film F is heat-sealed and formed into a bag shape at the portion folded inside the front cover of the book and the portion folded inside the back cover of the book. A protective cover having the shape shown in FIG. 1 was prepared, and then the protective cover was attached to the book. Next, the book with the protective cover attached was put into the shrink device, and when the protective cover was heat-shrinked at 120 ° C. for 10 seconds and brought into close contact with the book cover, warpage occurred on the front cover and back cover. It became. Prior to heat shrinkage, the protective cover had a lateral width l ′ of 256 mm, lateral lengths w3 and w4 of 68 mm, and a longitudinal length h ′ of 153 mm. Further, the width L ′ of the protective cover after heat shrinkage was 160 mm, the horizontal lengths W3 and W4 were 41 mm, and the vertical length H ′ was 140 mm.

Example 1
In Comparative Example 1, the non-heat-shrinkable film and the heat-shrinkable film in the front cover cover portion and the front cover turn-back portion (a1 in FIG. 2) and the back cover cover portion and the back cover turn-back portion (a2 in FIG. 2) The protective cover was heat-shrinked and adhered to the cover of the book in the same manner as in Comparative Example 1 except that the protective cover was replaced with a laminated film obtained by adhering the conductive polyester film F by dry lamination. The book cover could be tightly packed with a protective cover without any occurrence. When performing the dry lamination, a polyester-based adhesive LX-701 and an isocyanate-based curing agent KY-90 (both manufactured by DIC Graphics) were used. Further, no warpage occurred on the front cover and the back cover. Before heat shrinkage, the protective cover had a lateral width l ′ of 256 mm, a lateral length t ′ of 40 mm, lateral lengths w1 and w2 of 108 mm, lateral lengths w3 and w4 of 68 mm, and longitudinal length h ′ of 153 mm. Further, the width L ′ of the protective cover after heat shrinkage was 230 mm, the horizontal length T ′ was 20 mm, the horizontal lengths W1 and W2 were 105 mm, the horizontal lengths W3 and W4 were 66 mm, and the vertical length H ′ was 150 mm.

DESCRIPTION OF SYMBOLS 1 Protective cover 2 Front cover cover part 3 Back cover part 4 Back cover cover part 5 Front cover folding part 6 Back cover folding part 7 Book 7a Front cover 7b Back part 7c Back cover 7d Small book 8 Book cover 8a Cover cover turn 8b Back Look back on cover cover 9 Band a1-a3 Adhesive

Claims (6)

A book protective cover comprising a heat-shrinkable film and a non-heat-shrinkable sheet,
The book protection cover includes a front cover cover portion that covers the front cover of the book, a back cover portion that covers the back portion of the book, a back cover cover portion that covers the back cover of the book, and an inner side of the cover cover portion A front cover folded portion folded back, and a back cover folded portion folded inside the back cover cover portion,
In at least a part of the front cover cover part, the back cover cover part, the front cover folded part, and the back cover folded part, the heat shrinkable film and the non-heat shrinkable sheet are bonded , The book protective cover, wherein the non-heat-shrinkable sheet is at least one of a non-heat-shrinkable film and a non-woven fabric .   The book protective cover according to claim 1, wherein the heat-shrinkable film and the non-heat-shrinkable sheet are bonded to a part of the back cover portion.   The book protective cover according to claim 1, wherein the heat-shrinkable film is a polyester film.   The book protection cover according to any one of claims 1 to 3, wherein the book protection cover is formed in a bag shape in the front cover folding portion and the back cover folding portion.   A book to which the book protection cover according to any one of claims 1 to 4 is attached.   It is a manufacturing method of the book with a protective cover, Comprising: With the protective cover which has the process of attaching the book protective cover as described in any one of Claims 1-4 to a book, and the process of heat-shrinking the said book protective cover How to make a book.