JPH0450590B2 - - Google Patents

Description

[Detailed description of the invention]

Technical field The present invention relates to a transfer sheet for PPC (plain paper copying),
The present invention relates to a matte film used as a drafting film, a diazo second original drawing film, etc. Prior art A matting film is a plastic film whose main components are a thermoplastic resin such as an acrylic resin or an amino thermosetting resin such as a melamine resin, and a matting agent such as silica powder or glass powder. It is known to have a matte layer and an overcoat layer on top of which the main component is a polymer electrolyte and/or a water-soluble resin such as PVA. This kind of matte film is used as a PPC transfer sheet, drafting film, diazo second original drawing film, etc., so it is easy to write with a pencil, water-based or oil-based ink, eraser, and ink or toner with correction fluid (solvent). Erasability (or correctability), toner fixability (adhesion to toner), etc. are required. In addition, in relation to these properties, the overcoat layer must have sufficient surface hardness and solvent resistance so that it will not be damaged or dissolved during writing (especially with a hard pencil) or correction, and the heat fixation of the toner. At times, the material is required to have thermal stability to the extent that it does not change in quality or decompose. However, there is no conventional matted film having an overcoat layer that satisfies these properties at the same time. For example, in a matted film using a thermoplastic resin for the matted layer, the matted layer peels off when a toner image is corrected. It cannot be used as a transfer sheet, and if the matting layer uses an amino-based thermosetting resin, the amino resin decomposes during heat fixation of the toner and generates formaldehyde with an irritating odor, making the work environment worse. There was a problem. Purpose The purpose of the present invention is to improve writability, especially writability with water-based ink, erasability, toner fixation, surface hardness, solvent resistance, interlayer adhesion, especially adhesion between a matting layer and an overcoat layer, and heat It is an object of the present invention to provide a matted film that can satisfy both stability. Structure: The matted film of the present invention has a matted layer on at least one surface of a plastic film, the matting layer mainly comprising a thermosetting polyurethane resin made of a polyol resin and a polyisocyanate, a butyl methacrylate resin, and a matting agent. It is characterized by being provided with an overcoat layer whose main components are styrene, butyl methacrylate, and an acrylic acid or methacrylic acid copolymer. The thermosetting polyurethane resin used in the matting layer consists of a polyol resin and a polyisocyanate. Here, the polyol resin means a polymeric substance having two or more hydroxyl groups in one molecule, and specifically includes polyethylene glycol, polyester, polyether, and acrylic resin each having a hydroxyl group at its end. Commercially available products include Desmofene 800 manufactured by Nippon Polyurethane Industries, Ltd.
Nitsuporan 1100, Nitsuporan 1004, Nitsuporan 3023, Nitsuporan 121, Excelol 100, Dainippon Ink Chemical Industries, Ltd. (trade name: Epicron 730), Hitachi Chemical Co., Ltd. (trade names) Hitaloid 3008, Nitsuporan 3088, etc. Among these, acrylic polyol resins are particularly preferred. On the other hand, polyisocyanate is a compound having two or more isocyanate groups in the molecule, specifically tolylene diisocyanate, diphenylmethane-
4,4'-diisocyanate, triphenylmethane-p,p',p''-triisocyanate, 2,4-tolylene dimer, hexamethylene diisocyanate, naphthalene-1,5-diisocyanate, dicyclohexamethane-4,4 '-diisocyanate, polymethylene polyphenyl isocyanate,
Examples include a reaction product of 3 moles of tolylene diisocyanate and 1 mole of trimethylolpropane. In addition, commercially available products include Desmodyur T, Desmodyur M, Desmodyur R, Desmodyur T, Desmodyur H, manufactured by Bayer AG, West Germany.
15, product name Pyren T manufactured by DuPont in the United States,
Known products include DDM, Millionate MT, Millionate MR, Coronate L, and HL manufactured by Nippon Polyurethane Industries. Among these polyisocyanates, aliphatic polyisocyanates are particularly preferred because they are less likely to be deteriorated by ultraviolet light or the like. The ratio of polyol resin to polyisocyanate varies depending on the type of these components or the type of base film, but generally the equivalent ratio (NCO/OH) is 0.8 to 0.8.
2.0, preferably 1.0-1.6. If it is less than 0.8, the adhesion, solvent resistance, and stain resistance are insufficient;
If it exceeds this range, the drying properties of the paint will be poor, which is inappropriate in terms of production technology, and the adhesion will also be poor. The butyl methacrylate resin used in the matting layer is a homopolymer of n-butyl methacrylate or isobutyl methacrylate or a copolymer with other copolymerizable monomers. In the case of a copolymer, it is preferred to contain 50% by weight or more of n-butyl methacrylate or isobutyl methacrylate. Further, as the copolymerization component in this case, other ethylenically unsaturated monomers such as alkyl acrylate or alkyl methacrylate, styrene, and vinyltoluene are used. The above thermosetting polyurethane resin and butyl methacrylate resin are used as binders. The ratio of polyurethane resin to butyl methacrylate resin is preferably about 9/1 to 7/3 (by weight); if this ratio is less than 9/1, adhesion with the overcoat layer will be insufficient, and if it is more than 7/3 In this case, the stiffness, solvent resistance, and heat resistance of the film decrease. Examples of matting agents used in the matting layer include powders such as glass, silica, clay, titanium oxide, starch, and fused alumina. The average particle size of these powders is suitably in the range of 0.1 to 50μ, preferably 1 to 10μ. The ratio of matting agent and resin component is
0.05/1 to 2/1 (by weight) is preferable. This ratio
If it is 0.05/1 or less, the degree of matting (unevenness) on the surface of the matting layer is low, and therefore the writing ability with a pencil is poor.
Eraser erasability etc. deteriorate, and on the other hand, if the ratio exceeds 2/1, the strength of the matte layer decreases. In addition to the above materials, the matting layer also contains vinyl chloride.
Other resins such as vinyl acetate copolymers can be added. In this case, the amount of other resins added is preferably 80% by weight or less of the total resin amount in the matted layer. On the other hand, the resin used for the overcoat layer is a styrene/butyl methacrylate/acrylic acid or methacrylic acid copolymer, but this copolymer can be used in the form of various metal salts, especially water-soluble metal salts or ammonium salts. It's okay. The ratio of each monomer is not particularly limited, but is preferably in the range of styrene/butyl methacrylate/acrylic acid or methacrylic acid=1 to 3/1 to 3/1 to 3. When the styrene ratio is less than 1, the strength of the coating film decreases, resulting in poor writing and erasing properties with a pencil, while when it is more than 3, the adhesion to the matte layer or toner tends to decrease. If the butyl methacrylate ratio is less than 1, the adhesion to toner will be poor, and if it is more than 3, the coating film strength will tend to decrease. Furthermore, if the ratio of acrylic acid or methacrylic acid is less than 1, the receptivity to aqueous ink and therefore the writing properties will be poor, and if it is more than 3, the water solubility will increase and bleeding will tend to occur when adding aqueous ink. In addition, a matting agent such as silica or glass as described above may be added as a filler to the overcoat layer. As the plastic film support, films of polysulfone, polyphenylene oxide, polyester, polyamide, polyimide, polycarbonate, etc. are used. To make the matted film of the present invention, first, a polyol resin, a polyisocyanate, a butyl methacrylate resin, and a matting agent are dissolved or dispersed in a suitable solvent, and then coated on at least one side of a plastic film using a bar coater, roll coater, etc. After drying at about 100 to 120 DEG C., curing is performed by heat treatment at 150 DEG C. for about 5 minutes or left at room temperature for about a week to form a matte layer. Next, a styrene-butyl methacrylate-alkyl acid or methacrylic acid copolymer is dissolved in a suitable solvent, and this is applied onto the matte layer using the same coating method, dried at about 100 to 120°C, and then overlaid. A coating layer may be provided. The dry weight of the matte layer is preferably 5 to 15 g/m ² , and the dry weight of the overcoat layer is preferably 3 g/m ² or less. In the case of an overcoat layer, when the amount exceeds 3 g/m ² , the ease of writing with a pencil tends to decrease. Furthermore, as a solvent for the matting layer coating solution, any solvent that dissolves polyol resin, polyisocyanate, and butyl methacrylate resin can be used. Specifically, methyl ethyl ketone, ethyl acetate, triene, acetone, xylene, monochlorobenzene, etc. can be used. can be mentioned. On the other hand, examples of the solvent for the overcoat layer coating solution include water, isopropanol, toluene, ethyl acetate, and acetone. Effects With the above structure, the matte film of the present invention has excellent writability with a pencil or water-based ink, erasability with an eraser or correction fluid, adhesion to toner,
It satisfies all the properties required for a matted film, such as hardness, solvent resistance, interlayer adhesion, especially adhesiveness between the matted layer and overcoat layer, and thermal stability. Examples of the present invention are shown below. All parts are by weight. Example 1 Acrylic polyol resin (Hitalloid 3008 manufactured by Hitachi Chemical Co., Ltd.) 63 parts Polyisocyanate (Coronate HL manufactured by Nippon Polyurethane Co., Ltd.) 22 Butyl methacrylate ~ methyl methacrylate (weight ratio 9/1) copolymer with 40% toluene ~
Isopropanol (weight ratio 4:1) mixed solvent solution 20〃 Silica powder (Syroid manufactured by Fuji Davison Co., Ltd.)
308) 13〃 A matting solution consisting of a mixed solvent of ethyl acetate and toluene (weight ratio 3/7) 70〃 was applied to both sides of a 75 μm thick biaxially stretched polyester film with a dry adhesion amount of 9 g/l.
After coating with a bar coater so that the thickness is ² m2,
The mixture was dried by heating for 5 minutes and then cured at 150° C. for 5 minutes to form a matted layer. Next, an overcoat solution consisting of 33 parts of a 30% aqueous solution of styrene-butyl methacrylate-ammonium allylate (weight ratio 2/1/1) copolymer of 57 parts of water and 10 parts of isopropanol was applied onto both matted layers in a dry amount. are respectively
100℃ after coating with bar coater to give 0.8g/ ^m2
A matted film was prepared by drying for 1 minute to form an overcoat layer. Example 2 A matting liquid and an overcoat liquid with the following formulation were used, and the dry adhesion amount of the overcoat liquid was 1.2.
A matted film was prepared in the same manner as in Example 1 except that the amount was changed to g/m ² . Matting liquid formulation: Acrylic polyol (same as Example 1) 55 parts Polyisocyanate (same as Example 1) 19〃 40% of butyl methacrylate - hydroxyethyl methacrylate - styrene (weight ratio 14/1/5) copolymer Toluene solution 29〃 Silica powder (same as Example 1) 13〃 Ethyl acetate - toluene (weight ratio 3/7) 70〃 Mixed solvent overcoat liquid formulation: Styrene - butyl methacrylate - methacrylic acid (weight ratio 3/3/4 ) 30% aqueous solution of copolymer
33 parts Silica powder (Sidro S- manufactured by Fuji Davison)
244) 1.5〃 Water 50〃 Isopropanol 8〃 Comparative Example 1 A matted film was prepared in the same manner as in Example 1, except that an overcoat liquid having the following formulation was used. Styrene to butyl methacrylate (weight ratio 1/
1) 30% toluene solution of copolymer 33〃 Toluene 47〃 Ethyl cellosolve 20〃 Comparative example 2 A matted film was prepared in the same manner as in Example 1, except that an overcoat liquid having the following formulation was used. 30% aqueous solution of styrene-sodium methacrylate (weight ratio 1/1) copolymer) 33 parts Water 57 Isopropanol 10 Comparative example 3 As matting liquid Melamine resin (Yuban 60R manufactured by Mitsui Toatsu Co., Ltd.)
20 parts Vinyl chloride-vinyl acetate copolymer (same as Example 1) 10〃 Thermosetting acrylic resin (Mitsui Toatsu Co., Ltd. Aromatex MT-748) 75〃 Quartz glass powder (Tatsumori Co., Ltd. Crystallite FM)
-1) A matted film was prepared in the same manner as in Example 1, except that a liquid consisting of 45〃 Silica powder (same as Example 1) and 10〃 Methyl Cellosolve 90〃 was used. Next, each of the matted films obtained as described above was tested for toner fixability, writability with a pencil and water-based ink, erasability with an eraser, and thermal stability. The results are shown in the table below.

[Table] The test method is as follows. Writability: When written with a 4H pencil or water-based pen, it is evaluated on a 5-point scale, with 5 being able to write well and 1 being unable to write. Erasability with eraser: After writing with a 4H pencil and erasing with a plastic eraser, it is evaluated on a 5-point scale with 5 being completely erasable and 1 being not being able to erase at all. Toner fixability: After forming an image with a PPC copier (manufactured by Ricoh: FW-610), rub the resulting image area (3cm x 3cm) five times to adhere an adhesive tape to the surface of the image, and then peel it off to remove the toner. Check the peeling condition. Evaluation is made on a five-point scale, with 5 being no peeling at all and 1 being completely peeling. Thermal stability: Examine the presence or absence of formalin odor when repeatedly copied using a PPC copying machine, and if there is no formalin odor, it is considered good, and if it is present, it is judged bad. As can be seen from the above results, the matted film of the present invention has particularly excellent toner fixing properties compared to comparative products, and also has interlayer adhesion, writability, erasability, thermal stability, etc. required for a matted film. It fully satisfies the characteristics.

Claims (1)

[Claims] 1. On at least one side of the plastic film, a matting layer mainly composed of a thermosetting polyurethane resin made of a polyol resin and a polyisocyanate, a butyl methacrylate resin, and a matting agent, and a matting layer containing styrene, butyl methacrylate, and acrylic on top of the matting layer. A matted film comprising an overcoat layer containing an acid or methacrylic acid copolymer as a main component.