JPS63214499A - Sheet for desk mat made of vinyl chloride group resin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a desk mat sheet made of a vinyl chloride resin, which is formed by treating one or both sides of a vinyl chloride resin molded product. More specifically, the present invention relates to a desk mat sheet made of vinyl chloride M resin that has excellent stain resistance and durability.

``Conventional technology'' Conventionally, when documents copied using an electrostatic duplicator are sandwiched between desk mats or document holders made of vinyl chloride resin sheets containing plasticizers, or when documents are stored inside them, If the printed surface that has been copied onto paper comes into contact with the transparent cover of a desk mat or document holder, the printing ink will transfer to the cover in a very short time, contaminating the cover, and even cause both sides to stick together. There was a problem with the document being damaged. In particular, transparent desk mats and document holders are used for the purpose of making it possible to see the printed matter behind the cover*, so if copy ink contaminates the cover, it will pass through the cover and cause the printed surface to be seen. This was extremely inconvenient as it became impossible to read text.9

Similarly, in the case of tablecloths, Tabasco, curry powder, sauce, iodine tincture, etc., penetrated into the sheets in a very short period of time, causing changes in appearance, deterioration, and hygiene problems.

These phenomena are mainly caused by the migration properties and compatibility of plasticizers, stabilizers, etc. contained in the vinyl chloride resin sheet, and the following methods are available to improve these defects.

First, there is a method of using a plasticizer with low migration properties.

Plasticizers used in soft polyvinyl chloride films and the like are mainly low molecular weight plasticizers, and heptatarate plasticizers, particularly nooctyl heptatarate, are used in large quantities. These plasticizers have poor migration resistance and are easily lost from the molded article; therefore,
In order to improve migration resistance, a plasticizer with good migration resistance, such as a polyester plasticizer, is used. However, these plasticizers have many limitations such as slow plasticization during processing, poor water resistance, poor weather resistance when used outdoors, and high cost, which limit their use. Furthermore, as a method of surface treatment using low-temperature plasma, a method of modifying the surface of a molded product using low-temperature plasma of an inorganic gas has been proposed and put into practical use. This method works on the surface of a vinyl chloride resin molded product to form a crosslinked layer to prevent the migration of additives, and it does not change the internal characteristics of the molded product like electron beam irradiation or radiation irradiation. 8 These methods are described in Japanese Patent Application Laid-Open No. 55-120634.12, for example.
Publication No. 1049,121050.29504, Japanese Unexamined Patent Publication No. 5
6-2328.5833.62827.6282B, 6
Publication No. 5030, 67340.72023 and JP-A-5
This method is known from Japanese Patent No. 7-18737 and the like.

However, in these technologies, the plasma treatment is carried out in a pressure-resistant container, so the molded product before treatment is placed inside the container! In the step of carrying out Section I or transporting the processed molded product out of the container,
Continuous processing methods, regardless of batch processing methods, have the drawback of increasing processing costs due to restrictions on the cross-sectional shape, length, width, or weight of the molded product to be processed.

There is also a migration prevention technique using laminate. This is a technology for laminating and adhering a resin film that does not allow additives to penetrate onto the surface of a vinyl chloride resin molded product.

However, this technology cannot be applied to molded products with complex cross-sectional shapes, and even if you want to reduce the film thickness during film formation, there is a limit to the strength retention of non-permeable resin films. There is. There are limitations such as the need for a pretreatment process such as corona treatment to improve adhesion.

Furthermore, as a method for preventing the migration of additives to vinyl chloride resin molded articles, a technique is known in which the surface of the molded article is coated with a non-penetrating resin. These are
It is known from Japanese Patent Publication No. 28740, Japanese Patent Publication No. 50-31195, Japanese Patent Publication No. 57-15608, etc.

These technologies achieve the intended purpose by coating the surface of the molded product with a non-permeable resin whose main component is a liquid acrylic ester polymer. Although the adhesion is excellent (1), the ability to prevent the migration of additives to molded products is insufficient. VT Publication No. 52-6214 describes a method of partially crosslinking the coating film to improve migration prevention performance, but this improved technique also has the disadvantage that if the crosslinking reaction is carried out too much, the coating film becomes hard.
It has the disadvantage that it becomes brittle, cannot follow the base molded product, causes cracks in the coating film, or reduces the impact resistance of the molded product. The method of increasing the ms thickness is also not preferred because it reduces the impact resistance of the molded product.

[Problems to be Solved by the Invention] Under these circumstances, the present inventors have attempted to prevent the leaching and migration of additives from one or both sides of a vinyl chloride resin sheet, as well as the penetration of contaminants into the sheet. We investigated ways to effectively prevent this without being constrained by its composition and size.

"Means for Solving the Problems" The present inventors formed a mixed resin layer of silicone resin and acrylic ester resin on one or both sides of a vinyl chloride resin sheet, thereby preventing the leaching and migration of additives. Furthermore, it was discovered that the penetration of contaminants can be effectively prevented, leading to the present invention.

That is, the gist of the present invention is to coat a vinyl chloride resin sheet with a silicone resin having a film thickness of 0.2 to 10μ on one or both sides.
A sheet for a desk mat made of vinyl chloride resin is characterized by forming an acrylic acid ester PS resin mixed resin layer. The present invention will be explained in detail below.

The vinyl chloride resin sheet that is the base of the desk mat sheet of the present invention contains vinyl chloride resin, a plasticizer, and a stabilizer as main components, and if necessary, other resin additives such as a lubricant, an antistatic agent, and an antifogging agent may be added. It is a molded article made of a composition containing a UV absorber, a light stabilizer, a dye, a pigment, etc.

In the present invention, vinyl chloride resin includes not only polyvinyl chloride but also copolymers whose main component is vinyl chloride.
Examples of monomer compounds copolymerizable with vinyl chloride include vinylidene chloride, ethylene, propylene, acrylonitrile, maleic acid, itaconic acid, acrylic acid, methacrylic acid, and vinyl acetate. These vinyl chloride resins may be produced by any of conventionally known production methods such as emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization.

Examples of plasticizers used in vinyl chloride resin compositions include cy-n-octyl 7-thaletate, 2-ethylhexyl 7-thaleate, dibenzyl phthalate, and s-n-octyl 7-talate.
Heptatalic acid-based plasticizers such as nitrate, nododecyl 7-thaleate, and diundecyl 7-tally; Isophthalic acid group plasticizers such as dino-isooctyl isohetalate; 7-nopic acid-based plasticizers such as dino-n-butyl anovate and nooctyl adipate:
Maleic acid group plasticizers such as non-n-butyl maleate Citric a-based plasticizers such as nitri-1-butyl citrate: Itaconic acid group plasticizers such as monoitaconate Oleic acid group plasticizers such as nibutyl oleate: Glycerin mo/ Ricinoleic acid plasticizers such as ricilt: epoxidized soybean oil, epoxidized linseed oil, epoxidized fish oil, epoxidized tall oil fatty acid ester, epoxidized middle fat oil, epoxidized polybutanoene, methyl epoxy stearate, butyl epoxy stearate , epoxy stearin@-2-ethylhexyl, stearyl epoxy stearate, tris(epoxypropyl) in cyanurate, epoxidized castor oil, epoxidized 7-laurel oil, epoxidized linseed oil fatty acid ester, 3-(xenoxy)-1, Epoxy plasticizers such as 2-epoxypropane, bisphenol A-diglycidyl ether, vinylcyclohexene diepoxide, polycondensate of 2,2-bis(4-hydroxyphenyl)propane and epichlorohydrin: trioctylphos 7!
-),) Riphenylphos 7ate, triphrenol phosphate, triquinrenyl phosphate, nophenyloctyl phos 7ate, diphenylfrenyl phosphate,
Examples include phosphoric acid plasticizers such as triethylphenyl phosphate. These plasticizers may be used alone or in combination of two or more, but it is particularly preferable to use a phosphoric acid plasticizer.

The blending amount of these plasticizers is 2 parts per 100 parts by weight of vinyl chloride resin in order to balance the flexibility and strength of the molded product.
It is desirable to select from a range of 0 parts by weight or more, preferably from 40 to 100 parts by weight.

Stabilizers that can be used include calcium stearate,
Metal soaps such as zinc stearate, lead stearate, barium stearate, cadmium stearate, etc.: tribasic lead sulfate, dibasic lead phosphite, diptyltin laurate, diptyltin simalate, non-n-octyltin mercaptide, Examples include organic tin compounds such as dimethyltin mercaptide.

The vinyl chloride resin of the present invention may be mixed with the following additives as necessary.

Examples of lubricants that can be used are fats such as stearic acid, palmitic acid, mystylic acid, etc. Fatty acid amide lubricants such as nistearic acid amide, palmitic acid amide, methylene bis stearamide, and ethylene bis stearamide, ester lubricants such as nibyl stearate and butyl palmitate, or polyethylene wax, liquid paraffin, etc. can give.

Antistatic agents or antifogging agents that can be used include sorbitan surfactants such as sorbitan monostearate, sorbitan monopalmitate, and sorbitan monobenzoate; glycerin monolaurate, noglycerin monopalmitate, glycerin monostearate, etc. Glycerin-based surfactants: Polyethylene glycol-based surfactants such as polyethylene glycol monostearate and polyethylene glycol monopalmitate: Alkylene oxide adducts of alcohol phenol: Esters of sorbitan/glycerin condensates and organic substances, etc. can be given.

Usable UV absorbers include benzoate UV absorbers, benzophenone UV absorbers, benzo)
Examples include those classified as IJ azole-based external radiation absorbers, anoacrylate-based ultraviolet absorbers, phenyl salicylate-based ultraviolet absorbers, and the like.

Light stabilizers that can be used include 4-(7znylacetoxy)-2,2,6,6-titramethylpiveridine, 4-
(phenylacetoxy)-2,2,6,6-titramethylpiverinone, tris-(2,2,6゜6-tetramethyl-4-piperidyl)triazine-2,4,6-)licarboxylate, etc. Examples include hind amine compounds.

These various mm additives can be selected within the usual blending amount, for example, within the range of 5 parts by weight or less per 100 parts by weight of the vinyl chloride resin.

To blend the plasticizer and each M resin additive into the vinyl chloride resin, use conventional mixing/blending techniques such as Ebori Bonpregu, Banbury mixer, Super mixer, Henschel mixer, and other conventionally known blending machines. You can use the machine.

The resin composition thus obtained can be molded using methods known per se, such as melt extrusion molding (including the T-Guy method, In7reshi B method, and blow molding method), solution flow molding, etc. A rolling method, a calendar molding method, or an injection molding method may be adopted.

The acrylic ester resin in the silicone resin/acrylic ester resin used in the present invention is a polymer or copolymer whose main monomer is methyl acrylate, methyl methacrylate, ethyl methacrylate, etc. Among these, those whose main constituent monomer is methyl methacrylate are preferred. In addition, as the sub-constituent monomers, monomers copolymerizable with the above-mentioned main constituent monomers,
Examples include acrylic esters, methacrylic esters, halogenated vinyl compounds, halogenated vinylidene compounds, aromatic vinyl compounds, tsene compounds, olefin compounds, and the like.

The form of copolymer with these monomers may be any of random copolymers, block copolymers, graft copolymers, etc.

The polymerization method involves combining a predetermined amount of one or more of the above monomers together with an organic solvent for each polymerization, adding a polymerization initiator and, if necessary, a molecular weight regulator, and heating while stirring. Polymerize. Examples of polymerization initiators that can be used in this case include radical-generating catalysts such as a, a-7 zobisisobutyronitrile, benzoyl peroxide, and cumene hydroperoxide. Examples of molecular weight regulators include butyl mercaptan and n- dodecyl mercaptan, ter
Examples include t-dodecylmercaptan and β-mercaptoethanol.

The organic solvent for dissolving the acrylic ester P and the resin may be the same as the solvent used in the production of the acrylic ester resin.Specifically, for alcohols, for example, methanol, ethanol, etc. , +1−”f
Lovanol, isopropanol, n-butanol, 5e
Examples include e-butanol, tert-butanol, n-7-myl alcohol, isoamyl alcohol, tert-7-myl alcohol, n-hexyl alcohol, cyclohexanol, etc. In addition to the above alcohols, ethyl acetate, methyl ethyl ketone, tetrahydro 7-yl alcohol, etc. , hexane, toluene, xylene, chlorophore, etc.,
These can be used alone or in combination of 2111 or more.

The silicone resins in the silicone resin and acrylic ester resin used in the present invention include SiO7, R81O
=/2, R2S +O1R55io 1/2(R;H,
methyl silicone resin, phenyl methyl silicone resin, and an alkyd composed of a component that is a combination of the silicon-containing structural unit and a silicon-free structural unit. These are modified resins such as modified silicone resin, melamine-modified silicone resin, epoxy-modified silicone resin, acrylic-modified silicone resin, and urethane-modified silicone resin.

Alkyd-modified silicone is produced by the reaction between siloxane and alkyd, melamine-modified silicone is produced by co-condensation of butylated melamine resin and siloxanol, epoxy-modified silicone resin is produced by the condensation of epoxy resin and siloxanol, and acrylic-modified silicone resin is produced by acrylic resin. A urethane-modified silicone resin is synthesized by condensation of urethane and siloxanol, and a urethane-modified silicone resin is synthesized by condensation of urethane and siloxanol. Other functional groups such as vinylsilane groups, hydroxyl groups, amide groups, carboxyl groups, nitrile groups, and aldehyde groups may be bonded to the silicone resin skeleton.

It is preferable to mix acrylic ester P and resin with the silicone resin synthesized as described above in a solid content concentration range of 3 to 90% by weight. If it is less than % by weight, it has a stain-resistant effect, but the adhesion to the vinyl chloride resin molded product is weak and cracks occur.

Moreover, if the solid content concentration is 90% by weight or more, the adhesive force becomes strong and there is an effect of preventing cracks, but the stain resistance deteriorates.

The above mixed resin is preferably formed on one or both sides of a vinyl chloride resin molded article to a thickness of 0.2 to 10 μm, and the hardness of the mixed resin layer is preferably 3H or less on a pencil hardness scale. If the thickness is less than 0.2μ, the stain resistance effect will be poor. Also, 1
If it is thicker than 0 μ, the stain resistance is good, but if the sheet is rubbed or rubbed, the coated area will easily crack, making it unsuitable for practical use. Similarly, the pencil hardness may exceed 3H. If it is too large, it will be too hard and the coated part will not be able to follow the distortion of the base vinyl chloride resin, and cracks will occur even if the base vinyl chloride resin is slightly elongated.

Various known methods can be used as the coating method, such as a bar code method, a doctor blade coating method, a gravure roll coating method, a playfoot method, and a rod coating method.

After coating, the mixture is maintained at a temperature of 50° to 150° C. for 30 seconds to 5 minutes to form a silicone resin/acrylic acid ester resin mixture layer.

"Function" The vinyl chloride resin desk mat sheet according to the present invention is blended into the base resin by forming a silicone resin/acrylic ester resin mixed resin layer on one or both sides of the vinyl chloride resin sheet. It can suppress migration and leaching of additives such as plasticizers and stabilizers to the surface of molded products, and it also has excellent weather resistance and stain resistance.

"Example" Hereinafter, it will be explained in more detail with reference to Examples.

Preparation of soft vinyl chloride resin film Polyvinyl chloride resin (F'=1300) 100 octyl 7 tallate 50 Epoxidized soybean oil
2〃Ba-ZnX% composite stabilizer
2 Pigment 0.1 The above composition was mixed in a Henschel mixer, mixed with a calendar roll kept at 180°C, and then rolled to a thickness of 3
00μ film was adjusted to v4.

Preparation of acrylic acid ester resin Methyl methacrylate 45 parts by weight Butyl ivy acrylate 30 Butyl acrylate
5 2-Hydroxyethyl methacrylate 19 Methacrylic acid 1 Isopropyl alcohol
100 Benzoyl peroxide 1
[The above composition was charged into a reactor equipped with a heating and cooling device, and heated at 80°C for 3 hours while stirring in a N2 stream. Furthermore, 0.5 parts by weight of benzoyl peroxide was added.
The temperature was maintained at the same temperature for a period of time, and then cooled to room temperature to obtain a resin solution. Isopropyl alcohol was added to this solution so that the solid content was 20%, and acrylic ester P,
Resin was obtained.

The acrylic ester resin and silicone resin synthesized as described above were mixed and coated onto a soft vinyl chloride resin sheet using a percoater. A coating film was formed by heating the sheet at 130° C. for 2 minutes in an open gear.

Table 1 shows the thickness, stain resistance, and durability of the coated surface of the silicone resin/acrylic acid ester resin mixed resin layer.

The performance evaluation in Table 1 is as follows.

Stain Resistance> Each of the following contaminants was attached to the coated surface of the soft vinyl chloride resin film of the base.

・For Xerox printing paper, Ricoh printing paper, and facsimile printing paper, after WJ arrival at 45°C Xi 00 hours x arm weight ioog/c112, facsimile mark 1jAWk was evaluated for ink disappearance, and for others, the degree of contamination on the coated surface was evaluated. did.

- After dropping Tabasco, curry powder, sauce, and seed tincture liquid onto the coated surface, it was left for 24 hours, wiped off with a cloth, and the appearance was observed.

The notation is according to the following classification.

Items with no traces/disappearance 0 Items with slight traces/disappearance ○ Items with clear traces/disappearance Δ Signs/disappearance are severe
x Rub test The coated surface was observed according to Japanese Industrial Standards (JIS K6772).

Table 2 shows the mixing ratio of acrylic ester M resin in the silicone resin/acrylic ester resin, stain resistance, and durability of the coating film.

Table 3 shows the durability of the coating film based on hardness.

Table 3 Note) Use the following silicone resin.

Example 9 5R-2410 () - manufactured by Resilicon, silicone-based paint) Example 10 SR-2411 () - manufactured by Resilicon, silicone-based paint) Comparative Example 8 AY42-440 () - manufactured by Resilicon,
Silicone-based paint) Above silicone-based resin/acrylic ester M? The mixing ratio of the acrylic acid ester resin in the Jt resin was set to 5% by weight, and the mixture was applied to the base vinyl chloride M resin 111 film. The thickness of the coating film is 2μ.

Claims (3)

[Claims] (1) Silicone resin/acrylic acid ester resin with a film thickness of 0.2 to 10μ on one or both sides of a vinyl chloride resin sheet containing 20 parts by weight or more of a plasticizer per 100 parts by weight of vinyl chloride resin A desk mat sheet made of vinyl chloride resin, characterized by forming a mixed resin layer. (2) The mixing ratio of acrylic ester resin in silicone resin/acrylic ester resin is 3 to 90% by weight.
A desk mat sheet made of vinyl chloride resin according to claim 1, which falls within the scope of claim 1. (3) The vinyl chloride resin desk mat sheet according to claim 1, wherein the coating hardness of the silicone resin/acrylic acid ester resin is 3H or less in pencil hardness.