JP6360106B2 - Method for producing a film for hydraulic transfer - Google Patents

Description

The present invention relates to a method for producing a film for hydraulic transfer using a polyvinyl alcohol film roll (hereinafter, “polyvinyl alcohol” may be abbreviated as “PVA”) which is not easily broken when unrolled from the roll; Relates to a hydraulic transfer method using the hydraulic transfer film manufactured in the above.

  As a means for forming a printed layer for imparting design properties or improving surface physical properties on the surface of a molded body having uneven three-dimensional surfaces or curved surfaces, it is suitable for transfer onto a water-soluble or water-swellable film surface. A method using a hydraulic transfer film on which a printing layer is formed is known. For example, in Patent Document 1, after floating on the liquid surface of a liquid represented by water with the printing surface of the hydraulic transfer film facing up, various molded bodies that are transferred bodies are pushed in from above. In addition, a method for transferring a printing layer to the surface of a transfer medium using hydraulic pressure is described.

  By the way, the PVA film as the base film for hydraulic transfer used for the production of the hydraulic transfer film is continuously formed in the form of a long film, and both end portions (ear portions) are cut and removed. Or, after being cut in the length direction (MD) at the center of the PVA film in the width direction (TD) or other positions in order to obtain a width that matches the equipment used or the form of use, it is rolled. The roll is wound up, packed in the form of a roll, transported to a secondary processing manufacturer, etc., and then the unpacked roll is mounted on a feeding device, and the PVA film fed from there is subjected to secondary processing such as printing. Often used as a hydraulic transfer film.

  In such a case, there is a problem that the PVA film breaks when the PVA film is fed from the roll. This problem is particularly noticeable when high-speed printing is performed. In a continuous processing line, since it takes time to introduce the PVA film back into the processing apparatus, the breakage of the PVA film results in a large production loss.

JP 54-33115 A

The present invention has been made in order to solve the above-mentioned problems, and a method for producing a film for hydraulic transfer using a PVA film roll that is difficult to break when unrolled from the roll; and the hydraulic pressure produced by the method It is an object of the present invention to provide a hydraulic transfer method using a transfer film.

  As a result of intensive studies to achieve the above object, the inventors of the present invention can significantly reduce the occurrence of breakage when the PVA film is fed from a roll by cutting both ends using an ultrasonic cutter. I found. The present inventors have further studied based on the findings and completed the present invention.

That is, the present invention
[1] PVA film and cutting and a resulting Ru steps roll I taken up the PVA film cut into a roll, the step of feeding the polyvinyl alcohol film from the roll, the fed-out surface of the polyvinyl alcohol film A method for producing a film for hydraulic transfer , comprising a step of printing on the film ;
The PVA film subjected to cutting contains 1 to 20 parts by mass of a plasticizer with respect to 100 parts by mass of PVA,
The thickness of the PVA film to be cut is 10 to 100 μm, and in the cutting step, the position of the blade is fixed, the grooved roll is placed on the back side of the polyvinyl alcohol film, and the polyvinyl alcohol film is bent. A method for producing a hydraulic transfer film, wherein the PVA film is cut while being moved and the blade is vibrated at a frequency of 5 kHz or higher;
[2] The method for producing a film for hydraulic transfer according to the above [1], wherein the PVA film constituting the PVA film to be cut has a saponification degree of 80 to 99 mol%.
[3] The liquid according to [1] or [2], wherein a dissolution time (converted value when the thickness is 30 μm) when the PVA film to be cut is immersed in 20 ° C. water is 300 seconds or less. Production method of pressure transfer film ;
[4] Any one of the above [1] to [3], wherein the arithmetic average roughness (Ra) is 2 μm or less when the surface roughness of the cut surface of the cut PVA film is measured in the thickness direction of the film. Method for producing two hydraulic transfer films ;
[5] A process of floating a hydraulic transfer film produced by the method according to any one of [1] to [4] above on a liquid surface with a printed surface facing upward; A hydraulic transfer method comprising a step of pressing a transfer medium from above the pressure transfer film;
About.

According to the present invention, there is provided a method for producing a hydraulic transfer film using a PVA film roll that does not easily break when being unwound from the roll; and a hydraulic transfer method using the hydraulic transfer film produced by the method. Provided.

The present invention is described in detail below.
The manufacturing method of the cut | disconnected PVA film of this invention has the process of cut | disconnecting a PVA film, vibrating a cutter with a frequency of 5 kHz or more. By having such a process, the shape of the cut surface is controlled, and a PVA film that is difficult to break when being fed from a roll or the like is obtained.

  Although this invention is not limited at all, it is thought that the cause which a PVA film fractures | ruptures when letting out from a roll exists in welding of a roll end surface. That is, when moisture adheres to the surface of the roll, particularly the end face of the roll, the moisture enters from the end face of the roll and quickly spreads into the gaps of the PVA film, and further swells and dissolves the surface of the PVA film, and further into the PVA film. It is presumed that local welding occurs between the contacting PVA films by drying again while permeating. The welding between the PVA films produced in this way is strong and weak, but particularly strong welding that causes breakage causes swelling and dissolution after the whisker on the cut surface (the portion where the end surface is stretched during cutting) absorbs moisture. It is estimated that the whisker occurs when it comes into contact with another cut surface. Therefore, it is considered important to reduce the generation of whiskers as much as possible in order not to generate strong welding that causes fracture. And according to the manufacturing method of this invention which has the process of cut | disconnecting a PVA film, vibrating a cutter with the frequency of 5 kHz or more, generation | occurrence | production of the said whiskers can be reduced by it, and when it pulls out from a roll etc., it is hard to fracture | rupture. It is thought that a PVA film is obtained.

  The frequency when vibrating the blade needs to be 5 kHz or more, preferably 10 kHz or more, and more preferably 15 kHz or more. When the frequency is less than 5 kHz, a beard is likely to be generated on the cut surface, and the PVA film is likely to be broken when the sheet is fed from a roll. On the other hand, the frequency is preferably 50 kHz or less, and more preferably 45 kHz or less. When the frequency exceeds 50 kHz, there is a tendency that whiskers are easily generated on the cut surface.

  The above-described cutting is performed using a cutter that can cut the blade while vibrating the blade as well as a cutter commercially available as a so-called ultrasonic cutter, and can set the frequency when the blade is vibrated to 5 kHz or more. It can be carried out. By cutting the PVA film using such a cutter, the generation of whiskers on the cut surface is suppressed compared to the case of using a method that does not vibrate the blade such as the conventional shear cut method or leather cut method. It becomes possible to do.

  There is no restriction | limiting in particular in the material of a cutter, For example, high-speed steel, die steel, stainless steel, ceramics, a cemented carbide, etc. are mentioned. Further, the blade edge angle of the blade can be set within a range of 10 to 50 °, for example.

  Since the angle between the blade edge of the blade and the PVA film when cutting the PVA film (the angle between the direction parallel to the blade edge and the PVA film surface) can more effectively suppress the generation of whiskers on the cut surface, It is preferably within a range of 10 to 60 °, and more preferably within a range of 15 to 55 °. Further, when the PVA film is cut, it is preferable to bend the PVA film using a grooved roll because the generation of whiskers on the cut surface can be more effectively suppressed.

  There is no particular restriction on the cutting position when cutting the PVA film, for example, it is cut in the length direction (MD) or specified so as to remove both ends (ears) of the long PVA film after film formation For example, it can be cut in the length direction (MD) at the center of the width direction (TD) of the long PVA film or at other positions. In the case of removing both end portions, for example, ranges of 1 to 20 cm can be set as both end portions on the inner side from both ends of the PVA film to be cut. By cutting in the length direction (MD) of a long PVA film as described above, a PVA film that is difficult to break when being fed from a roll is obtained. Also, for example, when a sheet of PVA film is obtained by cutting in the width direction (TD) of a long PVA film, if the PVA film is cut while vibrating the blade at the above frequency, the width direction It becomes possible to suppress breakage at the cut surface of (TD).

  Cutting of the PVA film may be performed while fixing the position of the blade and moving (conveying) the PVA film, or may be performed while fixing the PVA film and moving the position of the blade, or moving the position of the blade. The PVA film may also be moved (conveyed) while being moved, but when cutting so as to remove both ends of the long PVA film, the PVA film may be continuously and stably cut. Since it can do, it is preferable to cut | disconnect, fixing the position of a cutter and moving (conveying) a PVA film. The movement (conveyance) speed of the PVA film at that time is preferably within the range of 20 to 200 m / min, since generation of whiskers on the cut surface can be more effectively suppressed, and 40 to 150 m / min. More preferably within a range of minutes.

  As described above, according to the manufacturing method of the present invention having the step of cutting the PVA film while vibrating the blade at a frequency of 5 kHz or more, it is possible to reduce the generation of whiskers on the cut surface, and thereby when feeding from the roll It is considered that a PVA film that is not easily broken is obtained. The degree of generation of the whiskers can be represented by the arithmetic average roughness (Ra) obtained when the surface roughness of the cut surface of the cut PVA film is measured in the film thickness direction. In the PVA film produced by the method for producing a cut PVA film of the present invention, the arithmetic average roughness (Ra) is preferably 2 μm or less, and more preferably 1.5 μm or less. When the arithmetic average roughness (Ra) is 2 μm or less, the occurrence of breakage such as when the roll is unwound from the roll is more effectively reduced. In this specification, the arithmetic average roughness (Ra) is defined by JIS B 0601: 2001.

  PVA film to be used for cutting and thus PVA constituting the cut PVA film are vinyl acetate, vinyl formate, vinyl propionate, vinyl butyrate, vinyl pivalate, vinyl versatate, vinyl laurate, vinyl stearate, Those obtained by saponifying a polyvinyl ester obtained by polymerizing one or more vinyl esters such as vinyl benzoate and isopropenyl acetate can be used. Among the above vinyl esters, vinyl acetate is preferable from the viewpoints of ease of production of PVA, availability, cost, and the like.

  The polyvinyl ester is preferably obtained using only one or two or more vinyl esters as monomers, and more preferably obtained using only one vinyl ester as a monomer. However, as long as it does not impair the effects of the present invention, it may be a copolymer of one or more vinyl esters and other monomers copolymerizable therewith.

  Examples of other monomers copolymerizable with the vinyl ester include, for example, α-olefins having 2 to 30 carbon atoms such as ethylene, propylene, 1-butene and isobutene; (meth) acrylic acid or a salt thereof; (Meth) methyl acrylate, (meth) ethyl acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, ( (Meth) acrylic acid esters such as t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate; (meth) acrylamide, N-methyl ( (Meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, diacetone (meth) acryl (Meth) acrylamide derivatives such as amide, (meth) acrylamide propanesulfonic acid or salts thereof, (meth) acrylamidepropyldimethylamine or salts thereof, N-methylol (meth) acrylamide or derivatives thereof; N-vinylformamide, N-vinyl N-vinylamides such as acetamide and N-vinylpyrrolidone; methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether, stearyl vinyl ether, etc. Vinyl ether; vinyl cyanide such as (meth) acrylonitrile; halogenated vinyl such as vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride; vinegar Allyl compounds such as allyl acid and allyl chloride; maleic acid or its salt, ester or acid anhydride; itaconic acid or its salt, ester or acid anhydride; vinylsilyl compound such as vinyltrimethoxysilane; unsaturated sulfonic acid be able to. Said polyvinyl ester can have a structural unit derived from 1 type, or 2 or more types of an above described other monomer.

  The proportion of structural units derived from the other monomers described above in the polyvinyl ester is preferably 25 mol% or less based on the number of moles of all structural units constituting the polyvinyl ester, and is 15 mol%. More preferably, it is more preferably 5 mol% or less. When the ratio exceeds 25 mol%, when the cut PVA film is used as a base film for hydraulic transfer, the affinity between the PVA film and the printed layer tends to decrease.

  The PVA may be modified with one or two or more types of graft copolymerizable monomers as long as the effects of the present invention are not impaired. Examples of the graft copolymerizable monomer include unsaturated carboxylic acids or derivatives thereof; unsaturated sulfonic acids or derivatives thereof; α-olefins having 2 to 30 carbon atoms, and the like. The proportion of structural units derived from the graft copolymerizable monomer in PVA is preferably 5 mol% or less based on the number of moles of all structural units constituting PVA.

  In the PVA, a part of the hydroxyl groups may be cross-linked or may not be cross-linked. Moreover, said PVA may react with aldehyde compounds, such as acetaldehyde and a butyraldehyde, etc. to form an acetal structure, and the said PVA does not react with these compounds and does not form an acetal structure. May be.

  The polymerization degree of the PVA is preferably in the range of 500 to 3000, more preferably in the range of 700 to 2800, and still more preferably in the range of 1000 to 2500. When the degree of polymerization of PVA is less than 500, the resulting PVA film has insufficient mechanical strength and tends to break. On the other hand, when the degree of polymerization of PVA exceeds 3000, the production efficiency in producing a PVA film may be reduced, and the water solubility of a PVA film, and hence a hydraulic transfer film using the PVA film, may be reduced. It may be difficult to perform hydraulic transfer at an economical process speed. In addition, the polymerization degree of PVA as used in this specification means the average degree of polymerization measured according to description of JIS K6726-1994.

  The saponification degree of the above PVA is preferably in the range of 80 to 99 mol%, more preferably in the range of 83 to 96 mol%, and still more preferably in the range of 85 to 90 mol%. . When the degree of saponification of PVA is less than 80 mol%, the water solubility of the cut PVA film, and hence the hydraulic transfer film using the PVA film, decreases, and hydraulic transfer is performed at an economical process speed. In addition, the PVA film used for cutting becomes too soft, and the value of the arithmetic average roughness (Ra) on the cut surface tends to increase. On the other hand, even when the degree of saponification of PVA exceeds 99 mol%, the water solubility of the cut PVA film or hydraulic transfer film is lowered, making it difficult to perform hydraulic transfer at an economical process speed. In addition, the PVA film used for cutting becomes too hard, and the value of the arithmetic average roughness (Ra) on the cut surface tends to increase. In this specification, the degree of saponification of PVA refers to the total number of moles of structural units (typically vinyl ester units) that can be converted into vinyl alcohol units by saponification and the vinyl alcohol units of PVA. The proportion (mol%) occupied by the number of moles of vinyl alcohol units. The degree of saponification can be measured according to the description of JIS K6726-1994.

  Flexibility can be imparted by including a plasticizer in the PVA film. The plasticizer is preferably a polyhydric alcohol, and specific examples thereof include ethylene glycol, glycerin, propylene glycol, diethylene glycol, diglycerin, triethylene glycol, tetraethylene glycol, and trimethylolpropane. The plasticizer content in the PVA film is preferably in the range of 1 to 20 parts by mass, more preferably in the range of 2 to 15 parts by mass with respect to 100 parts by mass of PVA. When the content of the plasticizer is 1 part by mass or more, it is possible to suppress the value of the arithmetic average roughness (Ra) from increasing on the cut surface because the PVA film used for cutting becomes too hard. it can. Moreover, generation | occurrence | production of the blocking of the PVA film used for a cutting | disconnection and also the cut | disconnected PVA film can be suppressed because content of a plasticizer is 20 mass parts or less.

  In addition, by adding a water-soluble polymer other than starch and / or PVA to the PVA film, it gives the mechanical strength required when forming a printed layer on the PVA film, and moisture resistance when handling the PVA film. Or the speed of softening due to absorption of the liquid when the hydraulic transfer film on which the printing layer is formed is floated on the liquid surface, spreadability on the liquid surface, time required for diffusion in the liquid, The degree of deformation and the like in the pressure transfer process can be adjusted.

  Examples of the starch include natural starches such as corn starch, potato starch, sweet potato starch, wheat starch, rice starch, tapioca starch, and sago starch; processed starches subjected to etherification, esterification, oxidation, etc. In particular, modified starches are preferred. The starch content in the PVA film to be cut and thus in the cut PVA film is preferably 15 parts by mass or less, more preferably 10 parts by mass or less with respect to 100 parts by mass of PVA. When the starch content is 15 parts by mass or less, it is possible to suppress the impact resistance of the PVA film or the hydraulic transfer film from being lowered and the process passability from being lowered.

  Examples of water-soluble polymers other than PVA include, for example, dextrin, gelatin, glue, casein, shellac, gum arabic, polyacrylic acid amide, sodium polyacrylate, polyvinyl methyl ether, a copolymer of methyl vinyl ether and maleic anhydride, Examples thereof include a copolymer of vinyl acetate and itaconic acid, polyvinyl pyrrolidone, cellulose, acetyl cellulose, acetyl butyl cellulose, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, sodium alginate and the like. The content of the water-soluble polymer other than PVA in the PVA film to be cut and thus in the cut PVA film is preferably 15 parts by mass or less with respect to 100 parts by mass of PVA, and more preferably 10 parts by mass or less. preferable. When the content of the water-soluble polymer other than PVA is 15 parts by mass or less, it is possible to suppress a decrease in solubility and dispersibility of the PVA film during hydraulic transfer.

  Also, by incorporating a boron compound and / or a surfactant into the PVA film, the speed of softening due to the absorption of the liquid when the hydraulic transfer film on which the printed layer is formed is floated on the liquid surface, the liquid surface It is possible to adjust the spreadability in the film, the time required for diffusion into the liquid, the degree of deformation in the hydraulic transfer process, and the like.

  As the boron-based compound, boric acid and borax are preferable. The content of the boron-based compound in the PVA film to be cut and thus in the cut PVA film is preferably 5 parts by mass or less and more preferably 3 parts by mass or less with respect to 100 parts by mass of PVA. When the content of the boron-based compound is 5 parts by mass or less, it is possible to prevent the water-soluble property of the PVA film or the hydraulic transfer film from decreasing and the hydraulic transfer process speed from decreasing.

  There is no restriction | limiting in particular as surfactant, Well-known anionic surfactant, cationic surfactant, nonionic surfactant, etc. can be used. The content of the surfactant in the PVA film to be cut and thus in the cut PVA film is preferably 5 parts by mass or less and more preferably 1 part by mass or less with respect to 100 parts by mass of PVA. When content of surfactant is 5 mass parts or less, it can suppress that a PVA film becomes easy to contact | adhere and a handleability falls.

  In addition to the above-described components, the PVA film can contain other components such as a heat stabilizer, an ultraviolet absorber, an antioxidant, a colorant, and a filler. The content of these other components in the PVA film to be cut and thus in the cut PVA film is usually preferably 10 parts by mass or less with respect to 100 parts by mass of PVA, although it depends on the type. It is more preferable that the amount is not more than part by mass. It can suppress that the impact resistance of a PVA film deteriorates because content of another component is 10 mass parts or less.

  The moisture content of the PVA film to be subjected to cutting and thus the cut PVA film is preferably 1% by mass or more, more preferably 1.5% by mass or more, and further preferably 2% by mass or more. preferable. It can suppress that the impact resistance of a PVA film falls and it becomes easy to tear because a moisture content is 1 mass% or more. Also, dust and dirt can be prevented from adhering to the PVA film due to static electricity. For example, when the cut PVA film is used as a base film for hydraulic transfer, printing is performed on the surface of the PVA film. Printing omission can be suppressed. On the other hand, the moisture content is preferably 6% by mass or less, and more preferably 4% by mass or less. When the moisture content is 6% by mass or less, for example, when the cut PVA film is used as a base film for hydraulic transfer, the PVA film is easily stretched when the PVA film is fed out from the roll of the PVA film. Thus, it is possible to suppress the blurring of the print pattern when printing is performed on the surface of the PVA film, or the occurrence of printing misalignment when multicolor printing is performed.

  The thickness of the PVA film to be subjected to cutting and thus the cut PVA film may be appropriately selected according to the use, but is usually within the range of 10 to 100 μm, preferably within the range of 20 to 80 μm, more preferably 30. It should be in the range of ˜50 μm. When the thickness is 10 μm or less, it is possible to suppress a decrease in process passability due to insufficient strength of the PVA film or the hydraulic transfer film. On the other hand, when the cut PVA film is used as a base film for hydraulic transfer because the thickness is 100 μm or less, the water-solubility of the base film for hydraulic transfer or the film for hydraulic transfer is reduced. It is possible to suppress a decrease in the transfer process speed.

  There is no particular limitation on the shape of the PVA film to be used for cutting and thus the cut PVA film, but it is long from the viewpoint of ease of printing when the cut PVA film is used as a base film for hydraulic transfer. It is preferable that it is a film. The length of the long film is preferably 1 m or more, more preferably 100 m or more, and further preferably 1000 m or more. As an upper limit of the length of a long film, 40000 m is mentioned, for example. Further, the width of the long film is preferably 50 cm or more after cutting, more preferably 80 cm or more, and further preferably 100 cm or more. When the said width | variety is 50 cm or more, there exists an advantage that it becomes easy to perform the printing in the case of using the cut | disconnected PVA film as a base film for hydraulic transfer. The width of the long film is preferably 4 m or less, and more preferably 3 m or less because production of a PVA film having a uniform thickness is easy.

  The PVA film to be cut can be formed by a casting method, an extrusion method, a melting method, an inflation method, or the like. The PVA film after film formation may be an unstretched film, or may be a uniaxially stretched or biaxially stretched film for the purpose of improving mechanical properties in accordance with the application.

  Moreover, in order to improve the printability of the PVA film when using the cut PVA film as a base film for hydraulic transfer, or to improve the slip property of the surface of the PVA film, a mat treatment is performed on the surface of the PVA film. Is preferably applied. Examples of the mat treatment method include an on-line mat treatment method in which the surface of the mat on a roll or belt is transferred to a film during film formation, and a method in which an emboss treatment is performed after the formed film is once wound into a roll. . The arithmetic average roughness (Ra) of the mat-treated surface is preferably 0.5 μm or more, and more preferably 1 μm or more, from the viewpoint of improving printability and slipping properties. As an upper limit of arithmetic average roughness (Ra), 10 micrometers is mentioned, for example. In addition, the maximum height roughness (Rz) of the mat-treated surface is preferably 1 μm or more, and more preferably 3 μm or more, from the viewpoint of improving printability and slipping properties. An example of the upper limit of the maximum height roughness (Rz) is 20 μm. In the present specification, the maximum height roughness (Rz) is defined by JIS B 0601: 2001.

  The PVA film produced by the method for producing a cut PVA film of the present invention is preferably wound into a roll to form a roll. By making it into a roll, transportation and storage of the PVA film are facilitated.

  There is no restriction | limiting in particular in the use of the PVA film manufactured by the manufacturing method of the cut | disconnected PVA film of this invention, For example, the raw film for manufacturing optical films, such as a polarizing film and retardation film, using the said PVA film Or can be used for water-soluble films. Examples of the water-soluble film include a hydraulic transfer base film, a drug packaging film, a seed packaging film, and a release film. Among these, conventionally, when the PVA film is cut, it is difficult to control the shape of the cut surface, and the effect of the present invention is more remarkably exhibited when used for the use of a water-soluble film that is easily broken when being fed from a roll. Is preferable.

  About the water solubility of the PVA film used for cutting in the case where the PVA film is used for a water-soluble film, and the cut PVA film, the dissolution time when the PVA film is immersed in water at 20 ° C. (thickness is 30 μm) Converted value) is preferably 300 seconds or shorter, more preferably 200 seconds or shorter, and even more preferably 100 seconds or shorter. On the other hand, if the dissolution time is too short, the handleability of the PVA film may be lowered. Therefore, the dissolution time is preferably 3 seconds or more. In addition, the said dissolution time can be measured by the method mentioned later in an Example.

  Although there is no restriction | limiting in particular in the method of controlling the melt | dissolution time of a PVA film, The kind of PVA to be used (polymerization degree, saponification degree, the kind of modification | denaturation, modification amount, etc.), the thickness of a film, the kind of containing components, such as a plasticizer, The above range can be easily adjusted by appropriately adjusting the amount, the film forming method and the conditions thereof. Specifically, for example, in the PVA to be used, the degree of polymerization is lowered; the degree of saponification is brought close to about 88 mol%; a modified species (other monomers that can be copolymerized with the above-described vinyl esters and graft copolymerizable) Monomer etc.) are more hydrophilic; by increasing the amount of modification, or by reducing the thickness of the PVA film; by increasing the plasticizer content, etc. The dissolution time can be shortened.

  The hydraulic transfer film of the present invention is obtained by printing on the surface of the PVA film produced by the above-described method for producing a cut PVA film. In performing the printing, the PVA film is fed out from the roll using the roll and printing on the surface of the fed PVA film can suppress the breakage of the PVA film when the roll is fed out. Preferred in the invention. There is no particular limitation on the printing method when printing on the surface of the PVA film, and a printing layer can be formed by adopting a known printing method, such as gravure printing, screen printing, offset printing, roll coating, etc. Can be adopted. The printing may be performed directly on the PVA film with printing ink, or may be performed by once forming a printing layer on another film and then transferring it to the PVA film. When printing directly on a PVA film with printing ink as in the former, there are cases where the composition of the printing ink is limited, there are problems with the drying process, color misregistration problems during multicolor printing, and the like. Thus, it is preferable to perform printing by once forming a printing layer on another film and then transferring it to a PVA film. A conventionally well-known thing can be used as printing ink used for printing.

  The above-mentioned hydraulic transfer film is floated on a liquid such as water with the printed surface facing upward, and hydraulic transfer can be performed by pressing a transfer target such as various molded bodies from above. As a more detailed hydraulic transfer method, for example, the first step of activating the printing layer by floating the hydraulic transfer film on the liquid surface with the printed side up and spraying an ink activator, etc. Second step of pressing the transferred body from above the hydraulic transfer film floating on the liquid surface so that the transferred surface is lowered, and the printing layer of the hydraulic transfer film is the surface of the transferred body The third step of removing the PVA film portion of the hydraulic transfer film after sufficiently adhering to the film, and the fourth step of sufficiently drying the transferred body having the printing layer transferred to the transferred surface. There is a hydraulic transfer method.

  There are no particular restrictions on the type of transfer material, for example, woody substrates such as wood, plywood, and particle board; various plastics; gypsum board; fiber cement boards such as pulp cement boards, slate boards, asbestos cement boards; calcium silicates Plates; Magnesium silicate plates; Glass fiber reinforced cement; Concrete; Plates of metals such as iron, stainless steel, copper, and aluminum; and composites thereof. The transferred body may have a flat surface, a rough surface, or an uneven shape, but may be a transferred object having an uneven solid surface or curved surface. It is preferable that the advantage of hydraulic transfer can be utilized more effectively.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by the said Example. In addition, the dissolution time when the PVA film to be cut is immersed in water at 20 ° C. (converted value when the thickness is 30 μm) and the surface roughness of the cut surface of the cut PVA film (arithmetic mean roughness) Each measurement method of (Ra)) is shown below.

Measuring method of dissolution time (converted value when thickness is 30 μm) when the PVA film to be cut is immersed in water at 20 ° C. A rectangular sample having a length of 40 mm × width of 10 mm is cut out from the PVA film, 50 mm A rectangular plate (hole) with a length of 35 mm and a width of 23 mm on a 50 mm plastic plate, the length direction of the sample is parallel to the length direction of the window, and the sample is the width direction of the window It was pinched and fixed so that it might be located in the center of.
On the other hand, 300 ml of water was put into a 500 ml beaker, and the water temperature was adjusted to 20 ° C. while stirring with a magnetic stirrer equipped with a 3 cm long bar at 280 rpm, and the sample fixed on the plastic plate was It was immersed in a beaker, taking care not to touch the bar of the magnetic stirrer. The time (second) until the sample piece dispersed in water completely disappeared after being immersed in water was measured, and this was taken as the dissolution time of the sample. And the conversion value at the time of setting the thickness of a PVA film to 30 micrometers was obtained with the following formula | equation.
Dissolution time when immersed in water at 20 ° C. (converted value when the thickness is 30 μm) (seconds) = [30 / PVA film thickness (μm)] ² × (dissolution time of sample (seconds))

Measuring method of surface roughness (arithmetic mean roughness (Ra)) of cut surface of cut PVA film A shape measurement laser microscope “VK-X200” manufactured by KEYENCE Corporation was used. Specifically, the PVA film cut from the manufactured roll is fed out, and the surface roughness is measured in the thickness direction of the film at any one of the cut surfaces at both ends in the width direction (TD), and the arithmetic average is obtained. Roughness (Ra) was determined.

[Example 1]
(1) Manufacture of roll A long PVA film (length 1000 m, width 700 mm, thickness 30 μm) is continuously fed from the roll, and a range of up to 10 cm is set inside each end of the fed PVA film as an ear part. In order to remove this, the PVA film was cut in the length direction (MD) using an ultrasonic cutter having a blade oscillated at a frequency of 20 kHz, and the obtained PVA film having a width of 500 mm was cut into a paper tube. A roll was wound up around a (cylindrical paper tube with an inner diameter of 75 mm and an outer diameter of 90 mm).
At this time, the long PVA film used for cutting is composed of PVA having a polymerization degree of 1700 obtained by saponifying a polyvinyl acetate homopolymer and a saponification degree of 88 mol%, and glycerin is used as a plasticizer. A PVA film having a water content of 3% by mass and containing 8 parts by mass with respect to parts by mass (dissolution time when immersed in water at 20 ° C. (converted value when the thickness is 30 μm) 39 seconds) was used. Further, as the ultrasonic cutter, a cemented carbide alloy blade having a blade angle of 30 ° and a thickness of 0.38 mm was used.
In cutting, the position of the ultrasonic cutter was fixed, a grooved roll was placed on the back side of the PVA film, and the PVA film was moved at a conveyance speed (feeding speed) of 40 m / min. The angle between the blade edge of the ultrasonic cutter and the PVA film was 45 °, and the bending angle of the PVA film by the grooved roll (the holding angle of the PVA film to the grooved roll) was 5 °.
The surface roughness (arithmetic mean roughness (Ra)) of the cut surface of the cut PVA film thus obtained was measured by the method described above and found to be 1.2 μm.

(2) Manufacture of a film for hydraulic transfer The roll manufactured in (1) is mounted on a feeding device in a room that is humidified and air-conditioned at a room temperature of 20 ° C. and a relative humidity of 60%, and the PVA film is transferred from the roll at a feeding speed of 30 m / min. Was continuously fed out, and printing was performed on one side of the fed PVA film to obtain a hydraulic transfer film.
Under the present circumstances, the frequency | count of the peeling sound of the PVA film in the end surface of a roll when paying out a PVA film from a roll, and the frequency | count of a fracture | rupture of a PVA film were counted. When this evaluation was performed on five rolls manufactured in the same manner as described above in (1) and the average value was calculated, the peeling sound was 0.2 times and the number of breaks was 0 times.

[Comparative Example 1]
(1) Manufacture of a roll Except having stopped the vibration of the ultrasonic cutter, it was set as the roll after cut | disconnecting the PVA film like (1) of Example 1. FIG.
The surface roughness (arithmetic average roughness (Ra)) of the cut surface of the cut PVA film thus obtained was measured by the method described above and was 1.5 μm.

(2) Manufacture of hydraulic transfer film For five rolls manufactured in the same manner as described above in (1), the number of peeling sounds and the number of breaks of the PVA film were the same as in (2) of Example 1. As a result, the peeling sound was 0.4 times and the number of breaks was 0.2 times.

Claims (5)

And cutting the polyvinyl alcohol film, and cut the polyvinyl alcohol film Ru give roll I taken up in a roll form process, a step of feeding the polyvinyl alcohol film from the roll, the fed-out surface of the polyvinyl alcohol film A method for producing a hydraulic transfer film comprising a step of performing printing ;
The polyvinyl alcohol film subjected to cutting contains 1 to 20 parts by mass of a plasticizer with respect to 100 parts by mass of polyvinyl alcohol,
The thickness of the polyvinyl alcohol film to be cut is 10 to 100 μm, and in the cutting step, the position of the blade is fixed, a grooved roll is placed on the back side of the polyvinyl alcohol film, and the polyvinyl alcohol film is bent. A method for producing a hydraulic transfer film, wherein the polyvinyl alcohol film is cut while the blade is vibrated at a frequency of 5 kHz or more. The manufacturing method of the film for hydraulic transfer of Claim 1 whose saponification degree of the polyvinyl alcohol which comprises the polyvinyl alcohol film with which it uses for cutting | disconnection is 80-99 mol%. 3. The hydraulic transfer according to claim 1, wherein a dissolution time (converted value when the thickness is 30 μm) when the polyvinyl alcohol film to be cut is immersed in water at 20 ° C. is 300 seconds or less . A method for producing a film . The liquid according to any one of claims 1 to 3, wherein the arithmetic average roughness (Ra) is 2 µm or less when the surface roughness of the cut surface of the cut polyvinyl alcohol film is measured in the thickness direction of the film. A method for producing a pressure transfer film . A step of floating the hydraulic transfer film produced by the method according to any one of claims 1 to 4 on the liquid surface with the printed surface facing upward, and above the floated hydraulic transfer film And a step of pressing the transfer body from the fluid pressure transfer method.