JPS6232876Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a desk mat that prevents the adhesion of printing ink, particularly ink from electrostatic copying machines.

Conventionally, desk mats made of soft vinyl chloride containing plasticizers can be used to print ink in a very short period of time when documents copied using an electrostatic copier are placed between the desk and the desk mat with the printed side facing up. The printing ink adhered to the desk mat, causing the document to be damaged when taken out, and the printing ink remained on the desk mat after the document was taken out, making it extremely unsightly in appearance. Particularly if the desk mat is transparent, if printing ink adheres to the desk mat, visibility will deteriorate, and characters on a new document sandwiched between the desk and the desk mat may overlap with the printing ink adhered to the desk mat and be read. I had the inconvenient problem of not being able to do it.

As a method to improve this problem, a method has been proposed in which a thin film of other synthetic resin that does not contain plasticizers, such as acrylic resin or polyester resin, is laminated, but the desk mat obtained by this method is However, since the elongation and flexibility of soft vinyl chloride sheets and other synthetic resin films are different, there is a problem that wrinkles appear when folded, and this has not led to practical use.

Another option is to use a soft vinyl chloride sheet for the desk mat using a plasticizer that does not migrate easily, but plasticizers that do not migrate easily are very expensive compared to general plasticizers that easily migrate. Therefore, it has a large economic disadvantage and has not yet been put into practical use. Only the surface layer of the desk mat is made of a soft vinyl chloride sheet using a plasticizer that migrates easily, and the lower layer is made of a soft vinyl chloride sheet that uses a plasticizer that easily migrates. A desk mat with a vinyl sheet in contact with the desk surface is also considered, but desk mats with this structure have excellent ink adhesion prevention properties immediately after manufacture, but over time, the underlying soft vinyl chloride sheet becomes There was a problem in that the plasticizer migrated to the surface layer and the ink adhesion prevention performance deteriorated significantly in a short period of time.

The present invention aims to improve these drawbacks of conventional desk mats and provide a desk mat that is inexpensive, has little ink adhesion, and has a long-lasting ink adhesion prevention performance.

That is, the desk mat of the present invention has a laminated sheet in which the surface layer is formed of a soft vinyl chloride sheet using a plasticizer that does not easily migrate, and the back layer is formed of a soft vinyl chloride sheet that uses a plasticizer that easily migrates. , a synthetic resin layer is formed between the soft vinyl chloride sheets to prevent the plasticizer in the soft vinyl chloride sheets from migrating to the soft vinyl chloride sheets.

The desk mat of the present invention uses a soft vinyl chloride sheet that uses a plasticizer that causes less migration of the surface layer and is in contact with the desk surface.

Plasticizers with low migration include dicyclohexyl phthalate, which is solid at room temperature, phthalate plasticizers such as phthalate esters whose alcohol has 9 or more carbon atoms, and polyhydric alcohol ester plasticizers such as dipentaerythritol fatty acid esters. , trioctyl trimellitate, trinonyl trimellitate, tridecyl trimellitate, and other trimellitic acid plasticizers, sebacic acid, adipic acid, phthalic acid, etc., and polyhydric alcohols such as polyethylene glycol and polypropylene glycol. These include polyester plasticizers, which are commercially available products, and epoxidized oils such as epoxidized soybean oil and epoxidized linseed oil. Of course, a plasticizer that easily migrates to the extent that there is no problem with migration may be used in combination.

Examples of plasticizers that easily migrate include phthalate ester plasticizers having an alcohol carbon number of 8 or less, such as dibutyl phthalate, dioctyl phthalate, and dihexyl phthalate.

The synthetic resin that forms the synthetic resin layer that prevents the plasticizer in the soft vinyl chloride sheet from migrating to the soft vinyl chloride sheet is a synthetic resin that has good adhesion to the soft vinyl chloride sheet and has the ability to prevent the plasticizer from migrating. Must be made of acrylic resin,
Examples include polyester resin, polyamide resin, polyethylene, polypropylene, and polyurethane resin. In order to form a synthetic resin layer that prevents the plasticizer of the soft vinyl chloride sheet from migrating to the soft vinyl chloride sheet, the synthetic resin may be laminated on the soft vinyl chloride sheet in the form of a film, or the synthetic resin may be laminated on the soft vinyl chloride sheet in the form of a film. Of the resins, those that can be used as paint may be applied to a soft vinyl chloride sheet and dried to form a synthetic resin layer. From the viewpoint of cost and plasticizer migration prevention effect, it is particularly preferable to apply an acrylic resin paint.

It seems that the purpose of the present invention can be achieved by simply laminating a soft vinyl chloride sheet using a plasticizer that migrates less and a soft vinyl chloride sheet using a plasticizer that easily migrates, but if they are simply laminated, Good results are shown immediately after lamination, but
Over time, the plasticizer in the soft vinyl chloride sheet transfers to the soft vinyl chloride sheet, and the sheet retains all the shortcomings of the conventional soft vinyl chloride sheet. A synthetic resin layer is essential to prevent plasticizer migration.

In addition, the vinyl chloride resin forming the soft vinyl chloride sheet used in the present invention includes vinyl chloride and other monomers such as ethylene, propylene, vinyl acetate, vinyl ether, acrylic ester, in addition to vinyl chloride homopolymer. Copolymers with methacrylic acid esters, maleic acid esters, etc., and blend resins with vinyl chloride resin and other resins are also included.

As for other additives used in the soft vinyl chloride sheet, commonly used additives such as stabilizers, lubricants, pigments, fillers, and ultraviolet absorbers can be used, and there are no restrictions at all.

An example of manufacturing the flexible vinyl chloride laminate sheet of the present invention will be described. The soft vinyl chloride laminate sheet 5 is made by separately processing a soft vinyl chloride sheet 1 using a plasticizer that does not easily migrate and a soft vinyl chloride sheet 2 using a plasticizer that easily migrates by calendering or extrusion processing. A synthetic resin film that prevents plasticizer migration is laminated on one side of one of the soft vinyl chloride sheets, or a synthetic resin paint that prevents plasticizer migration is applied and dried. Synthetic resin layer 3 to prevent migration
A synthetic resin layer 3 is formed on the other soft vinyl chloride sheet to prevent migration of the plasticizer.
The adhesive 4 is sandwiched between a soft vinyl chloride sheet 1 using a plasticizer that does not easily migrate and a soft vinyl chloride sheet 2 using a plasticizer that easily migrates.
This can be achieved by bonding or by thermal lamination. In order to further reduce adhesion of printing ink, satin-like unevenness may be formed at least on the surface that comes into contact with printing ink.

Since the desk mat of the present invention is constructed as described above, even if it comes into contact with documents copied by an electrostatic copier for a long period of time, copy ink will not adhere to it, and both sides are made of soft vinyl chloride sheets. Since there is no synthetic resin layer on the surface that prevents the transfer of plasticizer, there are no wrinkles even when folded, which is preferable.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views showing embodiments of the present invention, respectively. 1... Soft vinyl chloride sheet using a plasticizer with little migration, 2... Soft vinyl chloride sheet using a plasticizer that easily migrates, 3... Synthetic resin layer that prevents plasticizer migration, 4... Adhesion Agent, 5... desk mat.

Claims (1)

[Scope of utility model registration request] In a laminated sheet in which the surface layer is formed of a soft vinyl chloride sheet using a plasticizer that does not easily migrate, and the back layer is formed of a soft vinyl chloride sheet that uses a plasticizer that easily migrates, a soft vinyl chloride sheet and a soft vinyl chloride sheet are used. A desk mat with less plasticizer migration, which is formed by forming a synthetic resin layer between the vinyl sheet and the plasticizer to prevent the plasticizer in the soft vinyl chloride sheet from migrating to the soft vinyl chloride sheet.