JP2946830B2 - Simple writing adhesive sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple writing pressure-sensitive adhesive sheet, and more particularly to a writing pen with good writing and erasing properties.
The present invention relates to a simple writing pressure-sensitive adhesive sheet that can be attached to an arbitrary location and can be peeled and reused.

[0002]

2. Description of the Related Art Instead of a conventional blackboard using chalk, a whiteboard which can be written with a marking pen and erased with a cloth or the like has been used. In general,
The whiteboard is made of a rigid substrate with a ceramic or synthetic resin surface to make it easier for the marking pen ink to adhere to it and to provide writability. ing.

However, ceramics are not easy to manufacture,
The method of painting and baking a synthetic resin on the substrate surface is also very expensive because of low productivity. In addition, a plastic sheet is provided with a writing layer by processing with a cured resin and bonded to the substrate surface, but this is also expensive. Further, a magnet sheet or the like in which a magnet is attached to an erasable writable sheet is also known, but these are limited to a place where the magnet is attached.

[0004] In a structure similar to such a blackboard, the entire stationary area is large and the weight is large, so that production and transport are not easy. All of these are expensive due to materials, productivity, distribution handling, and the like.

As a synthetic resin for forming a writing layer of a whiteboard, a thermosetting resin such as a melamine resin or an unsaturated ester resin or an ultraviolet curable resin is used. The stain resistance and hardness are insufficient, and the erasability deteriorates when used repeatedly. And UV curing resin has sufficient stain resistance and hardness,
There is a disadvantage that the photopolymerization initiator and the photosensitizer contained in the coating material are decomposed and the surface of the writing layer is yellowed.

Further, the surface of the writing layer needs to have excellent smoothness, and if the surface is not sufficiently smooth, the erasability will be poor. In particular, when trying to erase a handwriting that has been left for a long time after writing, the dye or pigment of the marking ink that has entered the concave portion of the writing surface and cannot be easily wiped off can be erased without cleaning with water or a solvent. I can no longer do it.

Further, as an inexpensive and easy-to-use device that is attached to an arbitrary place and used, various tack papers having a back surface such as paper coated with an adhesive can be used. However, it is difficult to erase characters when the writing surface is used once with ordinary paper, and the handling of ordinary tack paper is troublesome, for example, when the paper is peeled off after use, the paper breaks or the adhesive remains on the sticking surface. If it fails, cleaning afterwards is difficult.

[0008]

The marking pen has good writability and the handwriting can be easily wiped off with a cloth or the like, and it can be used by sticking it anywhere without limiting the place, and it can be peeled off and re-used. An inexpensive and easy-to-use simple writing adhesive sheet that can be used is provided.

[0009]

According to the present invention, there is provided a sheet obtained by coating and curing an electron beam-curable resin on the surface of a substrate sheet having a smoother smoothness of 20 cmHg or less on the surface, and JIS-Z- on the back surface. A simple writing pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer having a 180-degree peeling method stainless steel plate having an adhesive force of 30 to 500 g as specified in [0237].

[0010]

The present inventors have conducted intensive studies to meet the above-mentioned demands. As a result, a writing layer of an electron beam-curable resin is provided on the surface of a specific base sheet having excellent smoothness, and the back surface of this sheet is provided. The present invention has been completed by providing a specific adhesive layer.

The surface smoothness of the base sheet used in the present invention on the side on which the writing layer is formed has a smoother smoothness of 20%.
It is important that the smoothness is not more than cmHg. If the smoothness exceeds 20 cmHg and the smoothness is poor, the coating amount of the writing layer must be increased, which is not preferable in terms of the quality of writing and erasability, and the operation and economy.

The base sheet has a smoother smoothness of 20.
If it is not more than cmHg, a general substrate sheet may be used. For example, a film sheet of polyester, polypropylene, polyethylene, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyamide, polystyrene or the like, a composite sheet thereof, a laminated paper, a coated paper,
Undercoat paper, single-side bleached kraft paper having good one-sided smoothness, and the like are used. In particular, for applications requiring low cost and ease, coated paper such as cast coated paper and art-coated paper is preferable from the viewpoint of processability and price.

In the present invention, the electron beam-curable resin paint used for forming the writing layer contains a film-forming component and a reactive diluent as main components, and may contain a solvent, a dye, a pigment, a filler and the like as necessary. It is cross-linked and cured in a few seconds by irradiating the coated surface with an electron beam.

The coating film-forming component usually includes an acryloyl group, a methacryloyl group, or another polymer having a polymerizable double bond in the molecule, an oligomer, a monomer, and the like. For example, polyester (meth) acrylate, Urethane (meth) acrylate, epoxy (meth)
Acrylates and the like are preferably used. In particular, polyester (meth) acrylate is more preferable in terms of excellent writing properties and stain resistance with a marking pen, and excellent surface curing of the cured coating film.

The reactive diluent is compounded to lower the viscosity of the above-mentioned film-forming component to facilitate the coating operation and to crosslink the film-forming component by irradiation with electron beams. These are usually polyfunctional oligomers and monomers. As the reactive diluent of the present invention, 2
Monomers having at least two acrylate groups and / or methacrylate groups are preferably used. Specific examples thereof include, for example, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, butazinol di (meth) acrylate, Pentyl glycol di (meth) acrylate, 1,6-
Examples include hexanediol di (meth) acrylate and diethylene glycol di (meth) acrylate.

Furthermore, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, N-vinyl-2-pyrrolidone, tetrahydrofurfuryl (meth)
Monofunctional monomers such as acrylates can be used in combination.

If the coating amount of the curable paint is too small, sufficient stain resistance and hardness cannot be obtained.
μm is preferable, and particularly preferably about 1 to 10 μm. Electron beam irradiation is preferably performed using an electron curtain type electron beam irradiation apparatus, but is not limited thereto, and irradiation apparatuses of various types and systems generally used may be used.

The writing layer of the present invention is excellent in the writing property of the marking pen, and can be easily wiped off with a cloth or the like at any time when the written characters are corrected or the handwriting becomes unnecessary.
Can be used repeatedly.

In the present invention, an adhesive layer having an adhesive strength of 30 to 500 g to a stainless steel plate by a 180-degree peeling method specified in JIS-Z-0237 is provided on the back surface of the writing layer sheet. If the adhesive strength is less than 30 g, there is a risk that the adhesive will peel off immediately after application, or that it will not adhere evenly and blisters will appear. On the other hand, if the adhesive strength is as high as 500 g or more, re-peeling cannot be performed as expected, so the regulation of the adhesive strength is important.

The adjustment of the adhesive force can be set in a range suitable for the application by selecting the adhesive, the tackifier and the auxiliary and adjusting the compounding. Further, a method of adjusting the adhesive force by mixing various fillers such as particles can also be adopted. The coating amount of the adhesive layer is 5 to 30 g / m ^2, more preferably 10 to 25 g / m
Adjusted in ² ranges. Since the coating amount is related to the adhesive strength, it is necessary to set the amount in accordance with the selection of the above materials and the adjustment of the mixture.

The pressure-sensitive adhesive comprises an adhesive, a tackifier, and an auxiliary. Examples of the adhesive include polyisoprene rubber,
Rubber resins such as polyisobutyl rubber, styrene butadiene rubber, butadiene acrylonitrile rubber, (meth) acrylate resin, polyvinyl ether resin,
Examples thereof include polyvinyl acetate resin, vinyl chloride vinyl acetate copolymer resin, polystyrene resin, polyester resin, polyamide resin, polychlorinated olefin resin, polyvinyl butyral resin, and the like.

Examples of tackifiers added to these adhesives in appropriate amounts include, for example, rosin, dammar, polymerized rosin, partially hydrogenated rosin, ester rosin, polyterpene-based resin, modified terpene, petroleum-based resin, and cyclohexane. Examples include pentadiene-based resins, phenol-based resins, styrene-based resins, xylene-based resins, and cumarone-indene-based resins. If necessary, a softening agent, a filler, an antioxidant and the like are added.

Further, by sticking a release sheet on the surface of the pressure-sensitive adhesive layer, handling of the simplified writing pressure-sensitive adhesive sheet at the time of use and storage is improved. Further, a release sheet can be used as a process paper at the time of applying the pressure-sensitive adhesive layer, and the release sheet can be bonded to a writing-erasable base material sheet.

[0024]

EXAMPLES The present invention will now be described specifically with reference to examples of the present invention, but it is needless to say that the present invention is not limited thereto. Unless otherwise specified, parts and% in Examples are parts by weight and% by weight, respectively.

Example 1 As a substrate sheet, the smoother smoothness of the surface was 3 cm.
Using a cast coated paper having a basis weight of 85 g / m ^{2 in} Hg, a prepolymer mixture of polyester polyacrylate and polyurethane polyacrylate (trade name: 78E204, manufactured by Mobil Sekiyu KK) was 1.5 μm on the cast finished surface ( (After curing) by a bar coater, and an electro-curtain type electron beam irradiation device (CB: 15
(Type 0, manufactured by ESI) with an irradiation dose of 1.5 Mrad to cure the resin component to obtain a writing layer sheet.

Next, an acrylic acid copolymer emulsion (manufactured by Seiden Chemical Co., Ltd., trade name: Cybinol X-389)
-446E ") and 100 parts of a polyepoxide compound (manufactured by Seiden Chemical Co., Ltd .: trade name" A-3 "), and then mixing and adding a pressure-sensitive adhesive to the release surface of a commercially available polyethylene laminate release paper. 2 as solids
It was applied so as to have a concentration of 5 g / m ² and dried with a hot air drier.
The back surface of the writing layer sheet was stuck to the pressure-sensitive adhesive applied surface to obtain a simple writing pressure-sensitive adhesive sheet.

This sheet had good writing and erasing properties with a marking pen, and handwriting 15 days after writing could be easily wiped off with a cloth. The JIS of this sheet
-Z-0237, 180-degree peeling method Adhesive strength to a stainless steel plate is 100 g. Peeling off the release paper, sticking the adhesive surface to the glass surface or metal surface, and repeating peeling and sticking. No stain was caused by the adhesive residue.

Example 2 As a substrate sheet, the smoother smoothness of the surface was 15c.
Example 1 was the same as Example 1 except that a coated paper having a mHg of 157 g / m ² and a basis weight of 157 g / m ² was used, and an acrylic acid copolymer emulsion (trade name “Olivine BPW-5222” manufactured by Toyo Ink) was used as an adhesive. Similarly, a simple writing adhesive sheet was obtained.

This sheet had good writing and erasing properties with a marking pen, and handwriting 15 days after writing could be easily wiped off with a cloth. The JIS of this sheet
-Z-0237, 180-degree peeling method Adhesive strength to a stainless steel plate is 450 g. Peeling off the release paper, sticking the adhesive surface to the glass surface and metal surface, and repeating peeling and sticking, No stain was caused by the remaining glue.

Comparative Example 1 As a substrate sheet, the surface smoother smoothness was 35c.
Same as Example 1 except that a light-weight coated paper having a mHg of 84 g and a basis weight of 84 g was used, and an acrylic acid copolymer emulsion (manufactured by Nippon Carbide Co., Ltd .: trade name "Nicazole TS-662") was used as an adhesive. I made it.

This sheet had good writing properties with a marking pen and good erasing properties immediately after writing, but handwriting after 15 days could not be completely wiped off with a cloth. The adhesive strength of this sheet was 1000 g. When the release paper was peeled off, the adhesive surface was stuck to the glass surface or the metal surface, and the sheet was torn when peeled after use.

[0032]

As is clear from the results of the examples, the simple writing pressure-sensitive adhesive sheet of the present invention was excellent in writability by a marking pen and excellent in erasability to wipe off with a cloth. In particular, handwriting that had passed a long time after writing could be easily wiped off with a cloth. And it could be stuck and used at any place, and when peeled off after use, it could be repeatedly used without tearing the paper or leaving the adhesive on the stuck surface.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁶ identification code FI D21H 19/24 D21H 27/00 27/00 1/34 J 5/00 B (58) Fields studied (Int. Cl. ⁶ , DB name) C09J 7/02-7/04 C09D 5/00 C09D 133/08 B32B 7/10 D21H 19/24 D21H 27/00 WPI / L (QUESTEL)

Claims (2)

(57) [Claims] 1. The smoother smoothness of the surface is 20 cmHg.
A sheet obtained by coating and curing an electron beam-curable resin on the surface of a base material sheet described below has a 180-degree peeling stainless steel plate adhesive force specified by JIS-Z-0237 of 30 to 500 on the back surface.
g. An adhesive sheet having an adhesive force of g. 2. The method according to claim 1, wherein the base sheet is coated paper.
Simple writing adhesive sheet as described.