JPH052325B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a laminated mat made by laminating a plurality of adhesive sheets each consisting of a support and a pressure-sensitive adhesive layer. To provide a laminated mat for dust removal, which is placed facing upward and reliably removes dust adhering to the soles of the footwear of people passing over it and dust adhering to the casters of the stretcher. be. <Prior art and its problems> In order to prevent dirt from being brought into rooms such as hospital operating rooms, electronic component assembly rooms, and optical component assembly rooms, a support and a pressure-sensitive adhesive layer are installed at the entrances of these rooms. A laminated mat for dust removal, which is made by laminating multiple adhesive sheets (usually 5 to 30 sheets), is placed with the adhesive layer facing upwards to remove dust attached to the soles of people's footwear, etc. It is common practice to collect and remove dust adhering to the casters of stretchers, luggage carriers, and the like. When a large amount of dust adheres to a laminated mat, only one sheet is peeled off from the mat, and a new adhesive layer surface is exposed. Matsuto is generally 300-800mm x 500-1500
The size is said to be mm. Such laminated mats are generally required to have the following characteristics. (a) Must have appropriate adhesion and be able to reliably remove dust. (b) Adhesive strength shall not be such as to cause walking difficulties for pedestrians. (c) There is no transfer of adhesive to the soles or casters of footwear (if it transfers, the adhesive will be brought into the room) (d) Even if you walk on the adhesive layer surface, the casters of stretchers etc. will not pass through it. Also, make sure that the top adhesive sheet does not peel off from the laminated mat and float up, or peel off and wrap around the caster. (e) When removing the top adhesive sheet after dust removal, it should be possible to peel it off smoothly with a small amount of force. Although the laminated pine that has been known so far generally satisfies the characteristics (a) to (c) above, one that satisfies both characteristics (d) to (e) has yet to be developed. The current situation is that this has not been done. For example, in order to satisfy property (d), if the peeling force between adhesive sheets (self-back adhesive force) is increased,
Not only is it not possible to satisfy the characteristic (e),
In some cases, even the characteristic (b) could not be satisfied. By the way, until now this type of laminated pine has
Mainly from the point of view of economy, a polyolefin film such as a polyethylene film has been used as the support, and an acrylic pressure-sensitive adhesive has been used as the pressure-sensitive adhesive layer. The peeling force against the back surface of the support (adhesion force on its own back surface) can be increased by adding an appropriate adhesion-imparting resin to the acrylic pressure-sensitive adhesive.
It can be increased to 300 to 500g/20mm width (180 degree peel adhesive strength tensile strength 300mm/min). However, according to the experiments conducted by the present inventors, in the combination of a polyolefin film and an acrylic pressure-sensitive adhesive layer as described above, it is possible to satisfy the characteristic (d) even if the peeling force increases. It turned out that it was not possible. For example, corona treatment is applied to a polyethylene film with a thickness of 60 μm, and an acrylic pressure-sensitive adhesive (an acrylic copolymer of 2-ethylhexyl acrylate: ethyl acrylate: acrylic acid = 70:30:5 (weight ratio)) is applied to the treated surface. When evaluating the characteristics of a laminated mat made by laminating 30 adhesive sheets (size 600 mm x 900 mm) made of a 10 μm thick adhesive sheet (with polyisocyanate added and optionally an adhesion imparting resin). It was as shown in Table 1.

[Table] From Table 1, it can be seen that by selectively adding an adhesion-imparting resin, it can be expected that the adhesive force on the back surface (peel force) will improve, but there is almost no increase in the adhesive force on the sole of the shoe. Furthermore, at a normal walking speed of 50 m/min, the adhesive sheet still peels off. Moreover, in the systems (Nos. 2 and 3) in which an adhesion-imparting resin was added to prevent peeling, the adhesive sheet had a high resistance when peeled, that is, it was very difficult to peel. The present inventors further investigated in detail the facts shown in Table 1, and found that peeling can be prevented by slowing down the walking speed, but peeling occurs when walking speed is increased. Examining this knowledge in more detail, as shown in the drawing, the change in the self-back adhesive force (peel force) due to peeling speed is that at the same speed as normal walking speed (50 m/min), the self-back adhesive force is large. It was found that the adhesive force on the back surface shows a large value as the speed decreases. <Means for Solving the Problems> The present invention provides a new laminated mat for dust removal that solves the drawbacks of the prior art, and includes:
The gist is a type of support selected from the group of polyethylene film, polypropylene film, and mixture film of polyethylene and polypropylene, natural rubber, styrene-butadiene-styrene block copolymer, and styrene-ethylene. -butylene-styrene block copolymer,
It is a laminated mat made by laminating a plurality of adhesive sheets each consisting of a type of pressure-sensitive adhesive layer selected from the group of butyl rubber and ethylene copolymer, and the peeling force when peeling the adhesive sheet from the mat is 3 m. /min or less peeling speed is 150g/20mm or less, 50
The peeling force is designed to be at least twice as strong when the peeling speed is 3 m/min or less than the peeling force when the peeling speed is 3 m/min or less. According to the present invention, a laminated mat is provided that has a large peeling force in the high-speed range when walking, and a small peeling force in the low-speed range during peeling work.
In particular, one that fully satisfies the properties (d) and (e) above can be obtained. EXAMPLES Examples of the present invention will be shown and specifically explained below. A pressure-sensitive adhesive containing rubber as a main component shown in Table 2 is prepared by a conventional method. This adhesive includes adhesion-imparting resins such as rosin, hydrogenated rosin esters, alkylphenol resins, styrene resins, petroleum resins, and softening agents such as paraffins, process oils, lubricating oils, low molecular weight rubbers, and DOP. ,
DBP, waxes, and other compounding agents such as anti-aging agents and pigments may be added as necessary. The adhesion-imparting resin and the softening agent are each 60 parts by weight or less, preferably 3 to 40 parts by weight, per 100 parts by weight of the rubber.
Parts by weight and preferably in the range of 3 to 40 parts by weight. The adhesive prepared in this way is applied to the corona-treated surface of a 60 μm thick polyethylene film to a thickness of 10 μm. In addition to the polyethylene film mentioned above, polypropylene film,
A mixture film of polyethylene and polypropylene is preferably used, but other plastic films, paper, nonwoven fabrics, etc. may also be used, and if necessary, these films may be coated with electrostatic materials such as conductive substances or surfactants. Antistatic ability may be imparted by adding an inhibitor in advance or by subjecting the surface to a surface treatment. Thirty adhesive sheets, each consisting of a support film coated with a pressure-sensitive adhesive, were laminated and cut into 600 mm x 900 mm to create a laminated mat for testing.

【table】

[Table] The following can be understood from Table 2.
In other words, if the peeling force (self-back adhesive force) when peeling the adhesive sheet from the laminated mat is designed to be greater at a peeling speed of 50 m/min than at a peeling speed of 3 m/min, the lower speed range The adhesive sheet does not peel off when walking or passing through a stretcher in both high-speed and high-speed ranges, and it can be easily peeled off after use, and the peeling force at a peeling speed of 50 m/min is 3 m/min. If the peeling force is designed to be at least twice as high as the peeling speed, preferably 2.5 to 14 times, it will not peel off when walking or passing through a stretcher, and the peeling operation can be performed easily.
The peeling force at a peeling speed of 3 m/min or less is 150 g/20 mm or less, preferably 130 g/20 mm or less, and the peeling force at a peeling speed of 50 m/min or more is
80-400g/20mm, preferably 130-400g/20mm
It is understood that there is no peeling when the film is removed and the peeling work can be easily performed. These facts can be clearly understood by comparing with Samples Nos. 8 and 9, which do not meet the above requirements. In addition, as shown in sample No. 6, in the EVA-based laminated mat, the vinyl acetate content is in the range of 3 to 55% by weight, and polyisocyanate is added to this.
0.5 to 10 parts by weight per 100 parts by weight of EVA, and 1 to 50 parts by weight of an adhesion imparting resin having a functional group capable of reacting with the NCO group of the polyisocyanate such as rosin resin or phenol resin. When using a pressure adhesive, although the peeling force in the high-speed range (self-back adhesive force) is not very high, it exhibits a unique phenomenon in that no peeling occurs at all, and the peeling process is easy. Even when the inventor ran the shoe through the stretcher at a speed of 200 m/min, not only was there no winding of the adhesive sheet around the caster, but also no transfer of the adhesive to the sole. <Effects> As explained above, the present invention is designed so that the peeling force in the high-speed range is greater than the peeling force in the low-speed range, so that the adhesive sheet does not peel off when walking or passing through a stretcher with casters, and moreover, dust removal is good. It is effective and easy to remove after use.

[Brief explanation of the drawing]

The figure is a graph showing the relationship between the peeling speed of a laminated mat and the adhesive force on its own back surface when an acrylic pressure-sensitive adhesive is used.

Claims (1)

[Scope of Claims] 1. A type of support selected from the group of polyethylene film, polypropylene film, and mixture film of polyethylene and polypropylene, and natural rubber, styrene-butadiene-styrene block copolymer, and styrene-ethylene. - A laminated mat formed by laminating a plurality of adhesive sheets each comprising a pressure-sensitive adhesive layer selected from the group of butylene-styrene block copolymer, butyl rubber, and ethylene copolymer, the mat being adhesively bonded from the mat. The peeling force when peeling off the sheet is when the peeling speed is 3 m/min or less.
A laminated mat characterized by being designed to have a peeling force of 150g/20mm or less and a peeling force at a peeling speed of 50m/min or more to be at least twice as large as the peeling force at a peeling speed of 3m/min or less. 2 Peeling force at peeling speed of 50m/min or more is 80
The laminated mat according to claim 1, which has a weight of 400 g/20 mm. 3. The laminated mat according to claim 1, wherein the ethylene copolymer is an ethylene-vinyl acetate copolymer. 4. Claim 3, wherein the vinyl acetate content of the ethylene-vinyl acetate copolymer is 3 to 55% by weight.
Laminated pine as described in section. 5. The laminated mat according to claim 1, wherein the main component of the pressure-sensitive adhesive layer is a mixture of an ethylene-vinyl acetate copolymer and a polyisocyanate. 6. The laminated mat according to claim 1, wherein the main components of the pressure-sensitive adhesive layer are an ethylene-vinyl acetate copolymer, a polyisocyanate, and an adhesion-imparting resin having a functional group that reacts with an NCO group. .