JP7231376B2 - solid adhesive - Google Patents

Description

The present invention relates to solid adhesives with masking members.

Adhesive tapes are widely used in the fields of construction, electronic materials, automobiles, etc., because they are easy to apply and have excellent application speed. For example, in the construction field, it is used for fixing building materials such as plywood, facing material, gypsum board, and cement board to supports such as steel frames and crosspieces.

In construction using an adhesive tape, the adhesive tape may be attached to the adherend after the position is adjusted. As an adhesive tape whose position can be adjusted, one having a masking member provided on an adhesive layer is known. For example, in Patent Document 1, at least one side of a double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer having a thickness of 9 to 20% of the thickness of the support is laminated on both sides of the support, and the coverage is 6 to 40%. , a non-tacky or slightly tacky masking member having a thickness of 10-100% of the substrate is laminated. As the masking member, for example, cotton thread or synthetic resin fiber knitted fabric, non-woven fabric, mesh, net, metal mesh, or the like is used.

When the adhesive tape is provided with a masking member and is brought into contact with the adherend without pressure, the masking member contacts and the adhesive layer hardly contacts the adherend. adjustment becomes possible. In addition, when the pressure-sensitive adhesive tape is pressed after the position adjustment, the masking material is embedded in the pressure-sensitive adhesive layer, so that the pressure-sensitive adhesive layer can adhere to the adherend with high adhesive strength.

Japanese Patent Application Laid-Open No. 2001-115114

In adhesive tapes, a separator is generally used for the purpose of protecting the adhesive surface, and even in adhesive tapes having a masking member, the separator is generally attached to the adhesive surface provided with the masking member. be.
However, in a solid adhesive such as an adhesive tape having a masking member and a separator attached to the adhesive surface, the adhesive layer may enter the inside of the masking member over time, and the position adjustment function may not be sufficiently exhibited. . On the other hand, solid adhesives such as pressure-sensitive adhesive tapes often fail to exhibit the inherent adhesive performance of the pressure-sensitive adhesive layer due to the presence of masking members, and there is also a demand for improved adhesive strength.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a solid adhesive with a masking member, which has an appropriate adhesive strength of the adhesive layer and can sufficiently exhibit a position adjusting function even after a separator is attached and stored for a long period of time. and

As a result of extensive studies, the present inventors have found that the masking member covers the adhesive layer, the thickness of the masking member and the adhesive layer, the load at 2% elongation of the separator, the apex of the spike portion of the masking member, and the adhesive The inventors have found that the above problems can be solved by adjusting the height difference between the layer and the surface, and completed the following invention. That is, the present invention provides the following [1] to [5].
[1] An adhesive layer, a masking member provided on at least one surface of the adhesive layer, and a separator provided on the one surface of the adhesive layer so as to cover the masking member,
The masking member is composed of a thread-like or strip-like member and has a spike portion, the thickness of the apex of the spike portion being the maximum thickness,
The masking member has a coverage of less than 20% with respect to the one surface of the pressure-sensitive adhesive layer, and the maximum thickness of the masking member is 6 to 70% of the thickness of the pressure-sensitive adhesive layer,
The separator has a load at 2% elongation of 42.7 N/24 mm or less, and in a cross section passing through two vertices of adjacent spikes of the masking member, a straight line connecting two vertices of the spikes and the vertices A solid adhesive having a height difference of 70 μm or more from the one surface of the pressure-sensitive adhesive layer existing between two points.
[2] The solid adhesive according to [1] above, wherein the pressure-sensitive adhesive layer on the one surface provided with the masking member has an adhesive strength retention rate of 30% or more.
[3] The solid adhesive according to [1] or [2] above, wherein the pressure-sensitive adhesive layer has a storage elastic modulus of 1.0×10 ⁵ Pa or more and 5.0×10 ⁸ Pa or less at 0 to 50°C.
[4] The solid adhesive according to any one of [1] to [3] above, which is in the form of a sheet or a roll.
[5] The solid adhesive according to the above [4], wherein in the rolled solid adhesive, the breaking elongation of the separator is 8% or more.

The present invention provides a solid adhesive with a masking member that can sufficiently exhibit a position adjusting function even after a separator is attached and stored for a long period of time while the adhesive strength of the adhesive layer is adequate.

BRIEF DESCRIPTION OF THE DRAWINGS It is typical sectional drawing which shows one Embodiment of the solid adhesive of this invention. FIG. 4 is a schematic plan view showing one surface of an adhesive layer provided with a masking member. FIG. 10 is a cross-sectional view for explaining a method of measuring the masking member-adhesive layer height difference, and shows the solid adhesive after the separator has been peeled off.

<Solid adhesive>
The solid adhesive 10 of the present invention comprises an adhesive layer 11, and a masking member 12 and a separator 13 provided on one surface 11A of the adhesive layer 11, as shown in FIG. The solid adhesive 10 is usually in the form of a sheet, or a roll formed by winding a sheet, and is generally called an adhesive tape.

The masking member 12 is composed of a thread-like or band-like member, and is provided on one surface 11A of the pressure-sensitive adhesive layer 11 . Here, the filamentous member refers to a member having a cross-sectional major axis to minor axis ratio close to 1 (for example, less than 2), and a belt-like member has a cross-sectional major axis to minor axis ratio of more than 1. However, in this specification, they are not clearly distinguished, and thread-like or band-like members are collectively referred to as linear members in this specification. The masking member 12 has an uncovered portion 12D that does not cover one surface 11A of the pressure-sensitive adhesive layer 11 between the linear members. When the masking member 12 is a mesh material, which will be described later, the uncovered portion 12D is an opening of the mesh material. The crossing angle between the linear members 12A and the linear members 12B may be 90° or may not be 90°, and may be, for example, 45° or more and less than 90°.

The masking member 12 is preferably made of a mesh material. The masking member 12 made of a mesh material is, for example, as shown in FIG. , and the linear members 12A and 12B are bonded by fusion bonding or the like at each of these intersections. The crossing portion is configured as a spike portion 12C having a greater thickness than other portions. The masking member 12 has the greatest thickness at the apex of the spike portion 12C, and the thickness at the apex of the spike portion 12C is defined as the maximum thickness D1 (see FIG. 3).

Also, the masking member 12 may be formed by stacking two or more mesh materials. When two or more mesh materials are stacked, they are preferably stacked so that the spikes of each mesh material are arranged at different positions. By arranging the spikes at different positions, the maximum thickness D1 becomes the same as when using one piece of mesh material.

Although the above-described mesh material is composed of linear members arranged in parallel along two directions, it may be composed of linear members arranged in parallel in three or more directions. . In the above description, an example in which the masking member 12 is a mesh material has been described. Instead, it may be a knitted fabric, a woven fabric, a braided fabric, or a thread having thick portions at regular intervals in one direction.
The linear member is not particularly limited, but may be in any form such as a monofilament, a yarn obtained by bundling a plurality of filaments and, if necessary, twisting them, or a braid such as a braid. Moreover, the linear member may have any shape such as a circular, rectangular, flat, or square cross section.

A separator 13 is provided on one surface 11A of the adhesive layer 11 so as to cover the masking member 12 . The separator 13 is generally provided to protect the adhesive layer 11 and is peeled off when the solid adhesive 10 is used.
The separator 13 is usually in contact with a portion of the adhesive layer 11 that is not covered by the masking member 12 , thereby being attached to the adhesive layer 11 . Although not particularly limited, the separator 13 is preferably curved so as to enter the uncovered portion 12D between the linear members of the masking member 12 as shown in FIG.
The separator 13 is not particularly limited as long as it can be easily peeled off from the adhesive layer 11. As will be described later, the separator 13 is provided with a release agent layer, or a resin film containing a surface modifier or the like. Others are used.

The solid adhesive 10 is used with one surface 11A of the pressure-sensitive adhesive layer 11 adhered to various adherends. It is possible to Specifically, after the separator 13 is peeled off, the solid adhesive 10 is brought into contact with the adherend without applying pressure or with a small pressure applied to the surface on which the masking member 12 is provided. While the masking member 12 contacts the adherend, the pressure-sensitive adhesive layer 11 hardly contacts the adherend. Therefore, the position of the solid adhesive 10 can be easily adjusted by sliding it in contact with the adherend.
Then, when the bonding position is determined by position adjustment or the like, a high pressure is applied to the solid adhesive material 10 by pressing or the like to form a structure in which the adhesive layer 11 enters the uncovered portion 12D of the masking member 12, thereby forming the adhesive layer. 11 may be adhered to the adherend. As a result, the pressure-sensitive adhesive layer 11 is pressure-bonded to the adherend, and the solid adhesive 10 is firmly adhered to the adherend.

In the present invention, the solid adhesive 10 satisfies the following requirements (A) to (D). The solid adhesive 10 satisfies the following requirements (A) to (D) so that the adhesive strength of the adhesive layer 11 is adequate, and the position can be adjusted even after storage for a certain period of time with the separator 13 attached. It can fully function.
(A) The maximum thickness D1 of the masking member 12 is 6 to 70% of the thickness D2 of the adhesive layer 11;
(B) The load at 2% elongation of the separator 13 is 42.7 N/24 mm or less.
(C) The masking member-adhesive layer height difference is 70 μm or more.
(D) The coverage of the one surface 11A of the pressure-sensitive adhesive layer 11 of the masking member 12 is less than 20%.

In the solid adhesive 10 of the present invention, the maximum thickness D1 of the masking member 12 is 6 to 70% of the thickness D2 of the pressure-sensitive adhesive layer 11, as shown in requirement (A) above. When the maximum thickness D1 is less than 6% of the thickness D2 of the adhesive layer 11, the masking member 12 sinks into the adhesive layer 11, and the masking member-adhesive layer height difference of requirement (C) is satisfied. It becomes difficult to set the thickness to 70 μm or more, and it becomes difficult to adjust the position of the solid adhesive 10 . On the other hand, when the maximum thickness D1 is more than 70% of the thickness D2, the pressure-sensitive adhesive layer 12 is less likely to come into contact with the adherend. As a result, the adhesive strength retention rate of the solid adhesive 10 is lowered, the adhesive performance is lowered, and, for example, it becomes difficult to fix a heavy adherend using the solid adhesive 10 . In addition, the separator 13 may not adhere to the pressure-sensitive adhesive layer 11 and the separator 13 may float.
The maximum thickness D1 of the masking member 12 is 10% of the thickness D2 of the adhesive layer 11 from the viewpoint of improving the adhesive strength retention rate and shear adhesive strength, which will be described later, of the solid adhesive 10 and enhancing the position adjustment function. 15% or more is more preferable, 20% or more is more preferable, 67% or less is preferable, 60% or less is more preferable, and 55% or less is even more preferable.

As shown in the requirement (B), in the present invention, the load of the separator 13 at 2% elongation is 42.7 N/24 mm or less. When the load at 2% elongation of the separator 13 is greater than 42.7 N/24 mm, the adhesive layer 11 enters the uncovered portion 12D of the masking member 12, and the masking member-adhesive layer height difference shown in requirement (C). becomes 70 μm or more.
Although the principle that the pressure-sensitive adhesive layer 11 enters the uncovered portion 12D when the load at elongation is increased by 2% is not clear, it is presumed as follows. That is, the separator 13 becomes rigid when the load at 2% elongation is high, and cannot be sufficiently deformed along the shape of the masking member 12, and the pressure-sensitive adhesive layer 11 is pulled at the contact portion with the pressure-sensitive adhesive layer 11. It is presumed that the pressure-sensitive adhesive layer 11 is caused to enter the uncovered portion 12D. Further, based on the same principle, the pressure-sensitive adhesive layer 11 is caused to further penetrate into the uncovered portion 12D with the lapse of time, thereby further reducing the height difference between the masking member and the pressure-sensitive adhesive layer with the passage of time.

On the other hand, when the load at 2% elongation is reduced to 42.7 N/24 mm or less, the separator 13 is sufficiently deformed along the shape of the masking member 12 to enter the uncovered portion 12D, thereby causing the pressure-sensitive adhesive layer 11 to expand. It is presumed that the masking member-adhesive layer height difference can be increased by preventing entry into the uncovered portion 12D. It also prevents the masking member-adhesive layer height difference from becoming smaller over time.
From the viewpoint of increasing the masking member-adhesive layer height difference, the load at 2% elongation of the separator 13 is preferably 40.0 N/24 mm or less, more preferably 20.0 N/24 mm or less. In addition, the lower the load at 2% elongation of the separator 13 is, the better from the viewpoint of increasing the height difference. Preferably, it is 0.5 N/24 mm or more.

As shown in requirement (C), the solid adhesive 10 has a masking member-adhesive layer height difference of 70 μm or more.
Here, the masking member-adhesive layer height difference means that, as shown in FIG. It means the height difference T between the straight line L connecting the points and the one surface 11A of the pressure-sensitive adhesive layer 11 existing between the two apexes. The height difference T means the shortest distance between the straight line L and one surface 11A of the adhesive layer 11, and the adjacent spikes 12C, 12C mean the spikes closest to each other. .
When the pressure-sensitive adhesive layer 11 enters the uncovered portion 12D and the height difference between the masking member and the pressure-sensitive adhesive layer is less than 70 μm, the masking member 12 hardly protrudes from the pressure-sensitive adhesive layer 11 . Therefore, when the solid adhesive 10 is brought into contact with an adherend, many portions of the pressure-sensitive adhesive layer 11 come into contact with the adherend even if pressure is not applied. can't do enough.

From the standpoint of facilitating position adjustment of the solid adhesive 10, the masking member-adhesive layer height difference should be as high as possible, preferably 75 μm or more, more preferably 90 μm or more. In addition, from the viewpoint of increasing the adhesive strength retention rate and shear adhesive strength of the solid adhesive 10, the masking member-adhesive layer height difference is preferably 300 μm or less, more preferably 220 μm or less, and still more preferably 160 μm or less. .

The solid adhesive 10 has a coverage of less than 20% with respect to one surface 11A of the pressure-sensitive adhesive layer 11 of the masking member 12, as shown in requirement (D). If the coverage is 20% or more, the exposed surface of the adhesive layer 11 is reduced, and the adhesive strength retention rate and shear adhesive strength of the solid adhesive 10, which will be described later, cannot be sufficiently improved. As a result, the adhesive performance is lowered, and it becomes difficult to fix a heavy adherend or the like with the solid adhesive 10, for example.
In order to increase the adhesive strength retention rate and shear adhesive strength, the lower the coverage, the better, preferably 18% or less, more preferably 14% or less, and still more preferably 10% or less. The coverage is preferably 2% or more, more preferably 5% or more, from the viewpoint of covering a certain area or more of the pressure-sensitive adhesive layer 11 with the masking member 12 and improving the position adjustment performance.

In the solid adhesive 10 of the present invention, it is preferable that the one surface 11A of the adhesive layer 11 has an adhesive strength retention rate of 30% or more. Here, the adhesive strength retention rate is a value calculated by the following formula.
Adhesion retention rate (%) = A/B x 100
In the above formula, A is the 90° peel adhesive strength of the adhesive layer 11 of the solid adhesive 10 on the one surface 11A side of the SUS plate. B is a solid adhesive having the same configuration as the solid adhesive 10 except that the masking member 12 was not provided, and the pressure-sensitive adhesive layer of the solid adhesive was measured in the same manner. Adhesion.

The solid adhesive 10 has an adhesive force retention rate of 30% or more, so that the adhesive performance inherent in the adhesive layer can be properly exhibited. From the viewpoint of improving the adhesion performance of the solid adhesive 10, the higher the adhesion retention rate, the better, more preferably 40% or more, and still more preferably 50% or more. In addition, from the viewpoint of ensuring the above-described constant coverage rate, the adhesive strength retention rate is, for example, 95% or less, preferably 90% or less.

The solid adhesive 10 of the present invention has a shear adhesive strength of, for example, 10 N/cm ² or more, preferably 20 N/cm ² or more. When the shear adhesive strength is at least these lower limits, it becomes possible to fix a heavy adherend with high adhesive strength. From the viewpoint of further improving adhesion performance, the shear adhesive strength is preferably 23 N/cm ² or more, more preferably 27 N/cm ² or more. Although the upper limit of the shear adhesive strength is not particularly limited, it may be, for example, 200 N/cm ² or less, or 100 N/cm ² or less.

The pressure-sensitive adhesive layer 11 of the present invention preferably has a storage modulus of 1.0×10 ⁵ Pa or more and 5.0×10 ⁸ Pa or less at 0 to 50°C. By setting the storage elastic modulus to the above lower limit or more, the masking member 12 is prevented from being buried inside the pressure-sensitive adhesive layer 11 more than necessary, and the position adjustment function is easily exhibited. Further, when the solid adhesive 10 is pressed, the masking member 12 is appropriately embedded in the pressure-sensitive adhesive layer 11 by setting it to the above upper limit or less, so that the adhesive performance of the solid adhesive 10 is sufficiently exhibited. The solid adhesive 10 can be adhered to the adherend with appropriate adhesive strength. Moreover, by setting the storage elastic modulus within the above range, it becomes easy to adjust the shear adhesive strength and the like of the adhesive layer 11 to an appropriate value.
From these viewpoints, the storage elastic modulus is more preferably 1.1×10 ⁵ Pa or more, more preferably 1.0×10 ⁸ Pa or less, and even more preferably 1.0×10 ⁷ Pa or less.
In addition, the storage elastic modulus at 0 to 50 ° C. can be confirmed by checking the storage elastic modulus at 0 ° C. and 50 ° C., and if the storage elastic modulus at 0 ° C. and 50 ° C. are both within the above range, they are within the numerical range. and

Although the breaking elongation of the separator 13 of the present invention is not particularly limited, it is preferably 8% or more when rolled. When the solid adhesive material is rolled into a roll, the separator 13 may be broken or wrinkled. can be prevented. From the viewpoint of increasing the strength of the separator 13, the elongation at break is more preferably 100% or more, and even more preferably 200% or more. Moreover, the upper limit of the elongation at break is not particularly limited, and the higher the better, but practically it is 1500%.

Next, the material and configuration of each layer will be described in more detail.
(masking member)
The masking member 12 is a non-adhesive member that cannot adhere to an adherend even when pressed. The masking member 12 is composed of a linear member as described above. Examples of linear members include olefin resins such as polyethylene resin and polypropylene resin, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, and polyamide resins. , acrylic resin, polyvinyl alcohol resin, polyurethane resin, polyvinyl chloride resin, aramid, polyarylate, and other synthetic resins. It may also be formed from natural fibers such as cotton, hemp, wool, and silk.

The maximum thickness D1 of the masking member 12 is not particularly limited, but is, for example, 40 μm or more, preferably 100 μm or more, more preferably 200 μm or more, and is, for example, 2500 μm or less, preferably 1200 μm or less, further preferably 800 μm or less. By setting the maximum thickness D1 of the masking member 12 within these ranges, it becomes easier to adjust the ratio of D2 to D1 within the above range.

Although the diameter of the linear member forming the masking member 12 is not particularly limited, it is, for example, 0.02 to 1.0 mm, preferably 0.1 to 0.4 mm. Also, in the masking member 12, the mesh pitch of the mesh material is, for example, 1 to 20 mm, preferably 3 to 10 mm. Having the mesh pitch and diameter of the masking member 12 makes it easier to adjust the coverage within the predetermined range described above.

(separator)
As the separator 13, for example, one comprising a separator base material and a release agent layer provided on at least one surface of the separator base material is used. The release agent layer can be formed by subjecting the separator substrate to release treatment. The separator 13 is arranged so that the surface provided with the release agent layer is in contact with the masking member 12 and the adhesive layer 11 .
In addition, the separator 13 may be provided with a release agent layer on both sides by performing a release treatment on both sides of the separator base material. For example, when the solid adhesive 10 is rolled into a roll, the other surface 11B of the pressure-sensitive adhesive layer 11 contacts the rear surface of the separator. Therefore, by providing the pressure-sensitive adhesive layers on both sides, it becomes easier to unwrap the roll-shaped solid adhesive material 10 .

Known release agents can be used for the release agent that constitutes the release agent layer. A release agent can be used.
As the separator base material, known base materials used for separators can be used, and examples thereof include paper, synthetic paper, synthetic resin film, and the like. Examples of paper include paper substrates such as woodfree paper, glassine paper, and coated paper, laminated paper obtained by laminating thermoplastic resins such as polyethylene and polypropylene on these paper substrates, and cellulose, starch, polyvinyl Examples include paper substrates that have been sealed with alcohol, acrylic-styrene resin, or the like. Examples of synthetic resin films include polyolefin resins such as polyethylene resins and polypropylene resins. Among these, polyolefin resins are preferable from the viewpoint of easy adjustment of load at 2% elongation and breaking elongation.
In addition, in the synthetic resin film, one type of resin may be used alone, but two or more types may be used in combination. When two or more resins are used in combination, the amount and type of each resin to be blended may be appropriately adjusted so that the elongation at break and the load at 2% elongation are within the desired ranges.

Moreover, the separator 13 does not necessarily need to have a release agent layer as long as it can be easily separated from the adhesive layer 11 . For example, a synthetic resin film mixed with a surface modifier or the like may be used. In the synthetic resin film containing the surface modifier, the surface modifier imparts a certain level of releasability to the film surface, so that both surfaces of the separator 13 have a certain level of releasability.
Examples of surface modifiers include olefin/silicone copolymers. As the synthetic resin film, the same synthetic resin film as used for the base material for the separator can be used. In the synthetic resin film, the compounding amount of the surface modifier is, for example, 0.1% by mass or more and 15% by mass or less, preferably 0.5% by mass or more and 10% by mass or less, based on the total amount of the film.

In the present invention, from the viewpoint of ensuring the above-described 2% elongation load and breaking elongation, it is preferable to use laminated paper or synthetic resin film as the separator 13 .
The thickness of the separator 13 is not particularly limited, but is, for example, 10 μm or more and 1000 μm or less, preferably 20 μm or more and 250 μm or less.

(Adhesive layer)
The adhesive constituting the adhesive layer 11 is not particularly limited, but examples thereof include acrylic adhesives, rubber adhesives, urethane adhesives, silicone adhesives, and the like. These may be used alone or in combination. Among these, it is preferable to use an acrylic pressure-sensitive adhesive from the viewpoint of facilitating adjustment of the storage elastic modulus within the above-described predetermined range.

The thickness D2 of the adhesive layer 11 is preferably 150 μm or more and 10000 μm or less. By setting the thickness to 150 μm or more, the masking member 12 can easily enter the pressure-sensitive adhesive layer 11 . Therefore, when the adhesive layer 11 is used to adhere the solid adhesive 10 to the adherend, the adhesive layer 11 sufficiently contacts the adherend and adheres the solid adhesive 10 to the adherend with high adhesive strength. It becomes possible to let In addition, by setting the thickness to 10000 μm or less, the masking member 12 is prevented from entering into the pressure-sensitive adhesive layer 11 more than necessary and the contact area of the masking member 12 with respect to the adherend is reduced, thereby improving the position adjustment performance. Easier to raise.
From the viewpoint of position adjustment performance and adhesive strength, the thickness of the adhesive layer is more preferably 300 μm or more, more preferably 600 μm or more, more preferably 6000 μm or less, and even more preferably 2000 μm or less.

(Acrylic adhesive)
Hereinafter, one embodiment of the acrylic pressure-sensitive adhesive used in the pressure-sensitive adhesive layer will be described in more detail. The acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive containing an acrylic polymer obtained by polymerizing a polymerizable monomer containing a (meth)acrylic acid alkyl ester-based monomer (A).
In this specification, the term "(meth)acrylic acid alkyl ester" refers to a concept including both acrylic acid alkyl ester and methacrylic acid alkyl ester, and the same applies to other similar terms. . In addition, the term "polymerizable monomer" includes not only compounds having no repeating unit, but also compounds that copolymerize with the (meth)acrylic acid alkyl ester monomer (A), such as the olefin polymer (C) described later. refers to the concept that the monomer itself may include those having repeating units.

[(Meth)acrylic acid alkyl ester-based monomer (A)]
(Meth)acrylic acid alkyl ester-based monomer (A) is an ester of (meth)acrylic acid and an aliphatic alcohol, and the number of carbon atoms in the alkyl group of the aliphatic alcohol is preferably 2 to 14, more preferably Alkyl esters derived from fatty alcohols that are 4-10 are preferred. When the number of carbon atoms in the alkyl group is within this range, the glass transition temperature (Tg) of the pressure-sensitive adhesive layer is adjusted to an appropriate temperature range, making it easier to adjust the shear adhesive strength and storage elastic modulus within the ranges described above.

Specific (meth)acrylic acid alkyl ester-based monomers (A) include, for example, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl ( meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate Acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate and the like.
Among these, n-butyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate and n-octyl (meth)acrylate are preferred, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate or combinations thereof are more preferred.
The (meth)acrylic acid alkyl ester-based monomers may be used alone, or two or more of them may be used in combination.

The (meth)acrylic acid alkyl ester-based monomer (A)-derived structural unit constitutes the main component in the adhesive, and its content is generally 30% by mass or more, preferably 30% by mass or more, based on the total amount of the adhesive. is 40% by weight or more, more preferably 45% by weight or more. Thus, by increasing the content of the (meth)acrylic acid alkyl ester-based monomer (A), it is possible to impart desired adhesive strength to the adhesive.
The content of the structural unit derived from the (meth)acrylic acid alkyl ester-based monomer (A) in the pressure-sensitive adhesive is substantially the same as the content of the (meth)acrylic acid alkyl ester-based monomer (A) in the pressure-sensitive adhesive composition described later. are the same, they can be expressed interchangeably. The same applies to components other than component (A), such as components (B) and (C) described below.

[Polar group-containing vinyl monomer (B)]
The polymerizable monomer preferably contains a polar group-containing vinyl monomer (B) in addition to the (meth)acrylic acid alkyl ester monomer (A). The polar group-containing vinyl monomer (B) has a polar group and a vinyl group. By using the polar group-containing monomer (B) in the pressure-sensitive adhesive layer, it becomes easier to adjust the Tg, storage modulus, shear pressure-sensitive adhesive strength, and the like of the pressure-sensitive adhesive layer.
Examples of the polar group-containing vinyl monomer (B) include carboxylic acid vinyl esters such as vinyl acetate, (meth)acrylic acid, carboxylic acids containing a vinyl group such as itaconic acid, and their anhydrides, 2-hydroxyethyl (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, caprolactone-modified (meth) acrylate, polyoxyethylene (meth) acrylate, and polyoxypropylene (meth) acrylate hydroxyl groups such as vinyl monomers having, (meth)acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinyllauryllactam, (meth)acryloylmorpholine, (meth)acrylamide, dimethyl (meth)acrylamide, N-methylol (meth)acrylamide , N-butoxymethyl (meth)acrylamide, and dimethylaminomethyl (meth)acrylate.
Among these, (meth)acrylic acid, carboxylic acids containing a vinyl group such as itaconic acid, and their anhydrides are preferred, (meth)acrylic acid is more preferred, and acrylic acid is even more preferred. These polar group-containing vinyl monomers (B) may be used alone or in combination of two or more.

When the polar group-containing vinyl monomer (B) is used, the content of the structural unit derived from the polar group-containing vinyl monomer (B) in the adhesive is 100 of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). It is preferably 1 to 15 parts by mass, more preferably 2 to 12 parts by mass, and still more preferably 3 to 10 parts by mass. By setting the content of the polar group-containing vinyl monomer (B) within such a range, it becomes easier to adjust the Tg, shear adhesive strength, storage elastic modulus, etc. of the pressure-sensitive adhesive layer to appropriate ranges.

[Olefin polymer (C)]
The polymerizable monomer preferably further contains an olefin polymer (C) having a polymerizable bond at its terminal. By using such an olefin polymer (C), the shear strength of the pressure-sensitive adhesive is increased, and the shear pressure-sensitive adhesive strength is easily adjusted within the above range. The polymerizable bond means an unsaturated carbon-carbon bond capable of polymerizing with a polymerizable monomer, and includes, for example, an unsaturated double bond, preferably a (meth)acryloyl group.
Examples of the olefin polymer (C) include polyolefins having (meth)acryloyl groups, such as polyolefins having (meth)acryloyl groups at only one end and polyolefins having (meth)acryloyl groups at both ends. . Polyolefins are polymers of aliphatic hydrocarbon compounds having double bonds such as ethylene, propylene, butane, butadiene and isoprene, or hydrogenated products thereof.

As the polyolefin having a (meth)acryloyl group only at one end, for example, a (meth)acryloyl group at one end prepared by reacting polyethylene having an epoxy group at one end with (meth)acrylic acid. and polyethylene having. In addition, polybutadiene having a (meth)acryloyl group at one end or a hydrogenated product thereof may be mentioned, and commercially available products thereof include "L-1253" manufactured by Kuraray Co., Ltd. and the like.

Further, as the olefin polymer having (meth)acryloyl groups at both ends, for example, a (meth) Examples thereof include polypropylene having an acryloyl group. Further, polybutadiene having (meth)acryloyl groups at both ends or a hydrogenated product thereof may be mentioned, and commercial products thereof include "TEAI-1000", "EA-3000" and "TE-2000" manufactured by Nippon Soda Co., Ltd. ”, “BAC-45” manufactured by Osaka Organic Chemical Industry Co., Ltd., and the like.
The olefin polymer (C) may be used alone or in combination of two or more.

Among the above-described olefin polymers (C), polyolefins having (meth)acryloyl groups at both or one end are preferable, and among them, polybutadiene having (meth)acryloyl groups at both or one end or hydrogenation thereof things are preferred.
When a polyolefin having (meth)acryloyl groups at both ends is used as the olefin polymer (C), the acrylic polymer can be polymerized in a network. Therefore, it becomes easy to increase the cohesive strength of the adhesive, and it becomes easy to adjust the shear adhesive strength and the like within the above desired range.
Furthermore, from the viewpoint of improving cohesive strength, shear adhesive strength, etc., the olefin polymer (C) includes an olefin polymer having a (meth)acryloyl group at one end and an olefin polymer having a (meth)acryloyl group at both ends. It is preferable to use together with an olefin polymer.

The olefin polymer (C) preferably has a number average molecular weight of 500 to 20,000, more preferably 1,000 to 10,000. The number average molecular weight may be measured by gel permeation chromatography (GPC) and calculated using a standard polystyrene calibration curve.
In addition, the content of the structural unit derived from the olefin polymer (C) in the adhesive is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). , more preferably 2 to 15 parts by mass, and even more preferably 4 to 12 parts by mass.

[Other monomers]
The polymerizable monomer may contain monomers other than (A) to (C) described above. Other monomers include styrenic monomers and polyfunctional monomers. Styrenic monomers include, for example, styrene, α-methylstyrene, o-methylstyrene, and p-methylstyrene.
Examples of polyfunctional monomers include monomers having two or more vinyl groups, preferably polyfunctional (meth)acrylates having two or more (meth)acryloyl groups. The use of polyfunctional monomers allows the formation of networks in acrylic polymers.
Specific polyfunctional monomers include hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, tris(2-hydroxyethyl). isocyanurate triacrylate, ethoxylated trimethylolpropane triacrylate, proxied trimethylolpropane triacrylate, proxied glyceryl triacrylate, neopentyl glycol adipate diacrylate, and the like.
When using other monomers, the content of structural units derived from other monomers in the adhesive is 0.5 parts per 100 parts by mass of structural units derived from (meth)acrylic acid alkyl ester monomer (A). to 15 parts by mass, more preferably 1 to 7 parts by mass, and even more preferably 1 to 5 parts by mass.

[Tackifying resin]
The acrylic pressure-sensitive adhesive may contain a tackifying resin from the viewpoint of improving adhesive strength. As the tackifying resin, a tackifying resin with low polymerization inhibition such as hydrogenated terpene resin, hydrogenated rosin, disproportionated rosin resin, petroleum resin, etc. is preferable. Among these, hydrogenated resins are preferred, and among them, hydrogenated petroleum resins are preferred because polymerization reaction is inhibited when the tackifier resin has a large number of double bonds.
The softening point of the tackifier resin may be about 95°C or higher from the viewpoint of improving the cohesive strength and adhesive strength of the adhesive, but preferably includes 120°C or higher, such as 95°C or higher and 120°C. A temperature of less than 120° C. or more and a temperature of 120° C. or more and 150° C. or less may be used together. The softening point may be measured by the ring and ball method defined in JISK2207.
The content of the tackifying resin in the acrylic pressure-sensitive adhesive is preferably 5 to 40 parts by mass, more preferably 7 to 35 parts by mass, with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). parts by mass, more preferably 10 to 25 parts by mass.

[Fine particles]
The acrylic pressure-sensitive adhesive may contain fine particles. By containing fine particles, it is possible to improve the adhesive force to an adherend having a rough surface and the cohesive force of the adhesive.
Examples of fine particles include inorganic hollow particles such as glass balloons, shirasu balloons, and fly ash balloons, organic hollow particles made of polymethyl methacrylate, acrylonitrile-vinylidene chloride copolymer, polystyrene, phenolic resin, etc., glass beads, and silica beads. , inorganic fine particles such as synthetic mica, and organic fine particles such as polyethyl acrylate, polyurethane, polyethylene, and polypropylene.
The content of the fine particles in the acrylic pressure-sensitive adhesive is preferably 0.1 to 15 parts by mass, more preferably 0.5 parts by mass, with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). to 10 parts by mass, more preferably 0.7 to 5 parts by mass.

[Other ingredients]
The acrylic pressure-sensitive adhesive used in the present invention contains various additives conventionally used in pressure-sensitive adhesives, such as plasticizers, softeners, pigments, dyes, photopolymerization initiators, and flame retardants, in addition to the components described above. You may

[Gel fraction]
The gel fraction of the acrylic pressure-sensitive adhesive is preferably 30 to 80% by mass. By making the gel fraction equal to or higher than the lower limit, it becomes easier to increase the cohesive strength of the adhesive, and it becomes easier to adjust the shear adhesive strength within the above range. Moreover, it becomes easy to raise the adhesive force of an adhesive by making it below an upper limit. From these viewpoints, the gel fraction is preferably 40 to 70% by mass, more preferably 45 to 65% by mass.
The gel fraction can be adjusted within the above range by appropriately adjusting, for example, the olefin polymer (C) having two or more (meth)acryloyl groups, the presence or absence of blending of a polyfunctional monomer, and the blending amount. It is possible. The gel fraction can be calculated from the following formula (1). The polymerizable monomer preferably contains at least one of a polyfunctional monomer and an olefin polymer (C) having two or more (meth)acryloyl groups in order to set the gel fraction within the above range. . Compounds having two or more functional groups, such as polyfunctional monomers and olefin polymers (C) having two or more (meth)acryloyl groups, may be collectively referred to as cross-linking agents.
Gel fraction (% by mass) = (B/A) x 100 Formula (1)
A: Weight of the adhesive layer (test piece) B: The adhesive layer (test piece) was immersed in tetrahydrofuran at 40 ° C. for 48 hours, and the dry weight of the undissolved portion of the adhesive layer after that

(Method for producing pressure-sensitive adhesive layer)
When using an acrylic adhesive, the adhesive constituting the adhesive layer can be obtained by irradiating the adhesive composition containing the polymerizable monomer described above with light to polymerize the polymerizable monomer. It is possible. In addition, the pressure-sensitive adhesive composition may contain at least one of the above-described tackifying resin, fine particles, and other components, if necessary.
More specifically, first, a polymerizable monomer, and optionally a tackifying resin, fine particles, and other components are put into a reaction vessel such as a glass vessel and mixed to form an adhesive composition. get
Then, in order to remove oxygen dissolved in the adhesive composition, an inert gas such as nitrogen gas is generally supplied to purge oxygen. Then, the pressure-sensitive adhesive composition is applied on a separator, or applied to a support such as a resin film, woven fabric, or non-woven fabric, and then irradiated with light to polymerize the polymerizable monomer to obtain a pressure-sensitive adhesive layer. be able to.
It is preferable that the process from the application or impregnation of the pressure-sensitive adhesive composition to the process of irradiating with light is carried out in an inert gas atmosphere or in a state in which oxygen is blocked by a film or the like.
In this production method, the pressure-sensitive adhesive composition obtained by mixing each component may be prepolymerized before being applied to a separator or a support in order to increase the viscosity.

Lamps that can be used to irradiate the pressure-sensitive adhesive composition with light include, for example, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and metal halide lamps. etc. Among these, chemical lamps are preferred. The light irradiation intensity when irradiating the adhesive composition with light varies depending on the presence or absence of a photopolymerization initiator, but is preferably about 0.1 to 100 mW/cm ² .

(rubber adhesive)
Next, the rubber adhesive used for the adhesive will be described. The rubber-based adhesive contains a rubber component and a tackifying resin, and it is preferable to use a styrene-isoprene block copolymer as the rubber component. The styrene-isoprene block copolymer preferably has a diblock ratio of 25 to 70% by weight, more preferably 30 to 65% by weight, and still more preferably 45 to 60% by weight. Here, diblock means a diblock composed of styrene and isoprene. The styrene-isoprene block copolymer exhibits sufficient adhesive strength when the diblock ratio is 25% or more, and tends to increase the shear strength when the diblock ratio is 70% by mass or less. The styrene-isoprene block copolymer includes not only diblocks but also those having three or more blocks such as triblocks composed of styrene, isoprene and styrene blocks.

Although the amount of styrene in the styrene-isoprene block copolymer is not particularly limited, it is preferably 14 to 24% by mass, more preferably 15 to 18% by mass. When the styrene content is 14% by mass or more, the adhesive becomes highly cohesive and tends to increase the shear strength. Moreover, when it is 24% by mass or less, the cohesive force becomes an appropriate level, and the adhesive force is easily expressed.
The molecular weight of the styrene-isoprene block copolymer is not particularly limited, but the weight average molecular weight is preferably 100,000 to 400,000, more preferably 150,000 to 250,000. The term "mass average molecular weight" as used herein refers to a molecular weight measured as polystyrene equivalent molecular weight by GPC (gel permeation chromatography).

Various tackifying resins can be used as the tackifying resin used in the rubber-based adhesive, but petroleum-based resins, terpene resins, and coumarone resins are preferably used. The tackifying resin may be used alone or in combination of two or more. However, at least one selected from petroleum-based resins and terpene resins and coumarone resins may be used in combination. preferable. Such a combination of tackifying resins makes it easier to improve the adhesive strength.
Examples of petroleum resins include aliphatic petroleum resins (C5 petroleum resins), alicyclic petroleum resins, and aromatic petroleum resins. family-based petroleum resins are preferred. Further, it is preferable to use a petroleum-based resin having a softening point of about 90 to 120°C.
As the terpene resin, those having a softening point of about 80 to 120° C. can be used, but those having a softening point of less than 100° C. are preferable from the viewpoint of ensuring adhesive strength. As the coumarone resin, one having a softening point of preferably 110 to 130° C., more preferably 115 to 125° C. is used in order to ensure cohesion.

The tackifying resin is preferably 60 to 250 parts by mass, more preferably 100 to 200 parts by mass, even more preferably 110 to 180 parts by mass, based on 100 parts by mass of the rubber component. By setting the blending amount of the tackifying resin within the above range, it becomes possible to improve the cohesive force and impart an appropriate adhesive force.
When a petroleum-based resin and at least one selected from a terpene resin and a cumarone resin are used in combination, the petroleum-based resin is preferably 50 to 200 parts by mass, preferably 60 to 150 parts by mass, with respect to 100 parts by mass of the rubber component. Parts by mass are preferable, and 60 to 110 parts by mass are more preferable. On the other hand, the terpene resin is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass, and even more preferably 30 to 50 parts by mass with respect to 100 parts by mass of the rubber component. Furthermore, the coumarone resin is preferably 10 to 60 parts by mass, more preferably 15 to 50 parts by mass, and even more preferably 20 to 40 parts by mass with respect to 100 parts by mass of the rubber component.
The rubber-based adhesive may contain the fine particles described above in the same manner as the acrylic-based adhesive, and the rubber-based adhesive may contain softeners, antioxidants, fillers, etc., as necessary. good too.

(urethane adhesive)
The urethane pressure-sensitive adhesive described above is not particularly limited, and examples thereof include urethane resins obtained by reacting at least a polyol with a polyisocyanate compound. Examples of the polyols include polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, and the like. Examples of the polyisocyanate compound include diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, and the like. These urethane adhesives may be used alone or in combination of two or more.
As the urethane adhesive, a urethane resin obtained by reacting a polyurethane polyol and a polyfunctional isocyanate curing agent may be used. Examples of the polyurethane polyol include those obtained by reacting the above-described polyol with a polyisocyanate compound, and those obtained by reacting a polyol, a polyisocyanate compound, and a chain extender such as a diamine. As the polyfunctional isocyanate-based curing agent, any compound having two or more isocyanate groups may be used, and the isocyanate compounds described above can be used.
In addition to the urethane resin, the urethane-based adhesive may contain the fine particles described above, and the urethane-based adhesive may contain a tackifying resin, a softening agent, an antioxidant, a filler, etc., as necessary. may contain.

(Silicone adhesive)
Examples of the silicone-based pressure-sensitive adhesive include addition-reactive, peroxide-curable, and condensation-reactive silicone-based pressure-sensitive adhesives. Among them, the addition reaction type silicone pressure-sensitive adhesive is preferably used from the viewpoint that it can be cured at a low temperature in a short time. The addition reaction type silicone pressure-sensitive adhesive cures when the pressure-sensitive adhesive layer is formed. When an addition-reactive silicone pressure-sensitive adhesive is used as the silicone pressure-sensitive adhesive, the silicone pressure-sensitive adhesive may contain a catalyst such as a platinum catalyst.
In addition, the silicone pressure-sensitive adhesive may contain fine particles, and may contain a cross-linking agent and various additives for controlling adhesive strength.

In the above description, the masking member is provided only on one surface 11A of the pressure-sensitive adhesive layer 11, but the other surface 11B may also be provided with a masking member and, if necessary, a separator. When masking members and separators are provided on the other surface 11B, they may or may not have the same configuration as the masking members and separators provided on the one surface 11A side. By providing the masking members on both surfaces 11A and 11B, the position of the solid adhesive 11 can be adjusted when bonding either surface.

The solid adhesive 10 of the present invention is preferably a double-sided pressure-sensitive adhesive tape without a substrate. A substrate-less double-sided adhesive tape has no substrate to support the adhesive layer 11, and not only one surface 11A of the adhesive layer 11 but also the other surface 11B serves as an adhesive surface to be adhered to an adherend. Since the solid adhesive 10 is a baseless double-sided adhesive tape, one adherend can be fixed to the other by adhering adherends to both surfaces 11A and 11B.
Specifically, after bonding the solid adhesive 10 to one adherend through the other surface 11B, the other adherend is adhered to the one surface 11A, and the one adherend is attached. It may be fixed to the other adherend. In this case, since the position can be adjusted as described above when the other adherend is adhered to the one surface 11A, the two adherends can be aligned and then fixed.

Moreover, the solid adhesive may be in the form of a sheet, or the sheet-like solid adhesive may be further wound into a roll. When the sheet-like solid adhesive material 10 is a baseless double-sided adhesive tape as described above, it is preferable that a separator is also attached to the other surface 11B so that both adhesive surfaces are protected by the separator.
Moreover, as shown in FIG. 1, the solid adhesive 10 is preferably wound into a roll shape with the separator 13 provided on one surface 11A and the other surface 11B exposed. As a result, the other surface 11B comes into contact with the back surface of the separator 13, and the separator 13 protects both surfaces 11A and 11B. Alternatively, the coil may be wound with another separator attached to the other surface 11B.

However, the solid adhesive 10 is not limited to a baseless pressure-sensitive adhesive tape, and may be a double-sided pressure-sensitive adhesive tape having a base. Specifically, a base material and an adhesive layer may be provided in this order on the other surface 11B of the adhesive layer 11 to form a double-sided adhesive tape. Further, the solid adhesive 10 does not have to be a double-sided adhesive tape. For example, it may be a single-sided adhesive tape in which a substrate is provided on the other surface 11B and only one surface 11A serves as an adhesive surface. .

The solid adhesive 10 of the present invention can be used in various fields, for example in the construction field. In the construction field, for example, the solid adhesive 10 is adhered to various building materials such as plywood, decorative material, gypsum board, and cement board via the other surface 11B, and then one surface 11A of the solid adhesive 10 is adhered. is adhered to a support such as a steel frame or crosspiece so that the building material can be fixed to the support by the solid adhesive 10 . In this case, since the position of the building material can be adjusted when it is fixed to the support, the building material can be attached to the correct position of the support.

The method for producing the solid adhesive of the present invention is not particularly limited. A solid adhesive 10 may be formed. At this time, after laminating the masking member 12 and the separator 13 on the adhesive layer 11, the masking member 12 and the separator 13 may be appropriately pressed by a laminator or the like. Alternatively, the solid adhesive 10 obtained in this way may be formed into a roll shape by removing the separator stuck on the other surface 11B of the pressure-sensitive adhesive layer 11 .

EXAMPLES The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

In addition, the measuring method of various physical properties is as follows.
[Thickness of each layer]
The thickness D2 of the pressure-sensitive adhesive layer and the thickness of the separator were obtained by measuring the thickness at arbitrary 10 points in each layer and calculating the average value thereof. In addition, the maximum thickness D1 of the mesh was obtained by measuring the thickness of 10 points where the peaks of the spikes are located and calculating the average value thereof.

[Storage modulus]
Measuring device: DVA-200 (manufactured by IT Keisoku Co., Ltd.), shear mode: 10 Hz, strain amount: 0.1%, temperature range: -100 ° C to 100 ° C, temperature increase rate: 10 ° C / min The storage elastic modulus at 0° C. and 50° C. was determined under the following conditions. The sample size was 60 mm long (with a grip distance of 25 mm) and 5 mm wide.

[Coverage]
The surface of the pressure-sensitive adhesive layer was observed from above to determine the ratio of the area of the portion provided with the masking member to the total area of the pressure-sensitive adhesive layer.

[Load at 2% elongation]
Based on the measurement method of JIS K 7127, the load was measured when the distance between the two marked lines on the test piece was elongated by 2% from the original level. The measurement speed was 50 mm/min.
[Breaking elongation]
Based on the measuring method of JIS K 7127, the elongation rate was measured when the test piece was stretched until it broke.

[Masking member - adhesive layer height difference]
At an arbitrary position, as shown in FIG. 3, after peeling off the separator 13, the solid adhesive 10 is cut along a cross section passing through two vertices of the adjacent spikes 12C, 12C of the masking member 12, digitally Observation was made with a macroscope (VHX-5000 manufactured by KEYENCE) at a magnification of 100, and the height difference T was measured by the method described in the specification. The same measurement was repeated at three arbitrary points, and the three-point average value was taken as the masking member-adhesive layer height difference.

[Shear adhesive strength]
A 15 mm wide×15 mm long solid adhesive was cut to both sides, and a SUS plate was attached to each side of the adhesive by reciprocating a 2 kg pressing roller twice, and left at 23° C. for 1 hour. Under an environment of 23° C. and 50% RH, the solid adhesive material with SUS plates attached on both sides was pulled in the shear direction at a tensile speed of 300 mm/min to measure the shear strength at break. The same measurement was performed three times, and the three-point average was taken as the shear adhesive strength.

[Adhesive strength retention rate]
The 90° peel adhesive strength of the adhesive layer of the solid adhesive obtained in each example and comparative example to a SUS plate was measured. Let A be this peel adhesive strength. The 90 peel adhesive strength was measured according to the JIS Z 0237 measurement method. When the solid adhesive was press-bonded to the SUS plate, a load using a roller of 2000 g was applied.
In addition, except that the masking member was not provided, a solid adhesive was prepared in the same manner as the solid adhesives of each example and comparative example, and the pressure-sensitive adhesive layer of the solid adhesive was similarly 90°. Peel adhesion was measured. Let B be this peel adhesive force. Using the obtained peel adhesive strengths A and B, the adhesive strength retention rate was measured according to the following formula.
Adhesion retention rate (%) = A/B x 100

Solid adhesives were evaluated according to the following criteria.
[Adhesive strength judgment]
Based on the adhesive strength retention rate obtained above, the adhesive strength was determined according to the following evaluation criteria.
○: 50% or more
△: 30% or more and less than 50% ×: less than 30%

[Temporal position adjustment]
After the solid adhesive was produced, it was left at room temperature of 23° C. and humidity of 50% RH for 7 days. After that, cut out two pieces of solid adhesive material to 30 cm × 1000 cm, paste them on two vertical sides of a frame of 1500 cm long × 1500 cm wide and 40 cm wide, and lightly press the frame against the plasterboard to check the actual position adjustment performance It was evaluated according to the following evaluation criteria.
◯: The slide could be moved over a distance of about 50 cm without being caught.
Δ: It can be slid, but it feels a little stuck when moved. Paper material on the surface of gypsum board is not damaged by movement.
x: There is a catch, and the distance of about 10 mm cannot be moved. Also, if you try to move it, the paper material on the surface of the gypsum board will be damaged.

[Separator appearance]
The separators in the solid adhesives of each example and comparative example were observed and evaluated according to the following evaluation criteria. When forming a roll, the film was wound with the separators adhered on both sides.
◯: The separator adhered without shifting from the surface on which the pressure-sensitive adhesive layer was provided. Furthermore, the separator does not distort or break when rolled.
x: The separator is displaced from the surface on which the adhesive layer is provided, and the adhesive layer is exposed. Alternatively, the separator may be distorted or broken when rolled.

[comprehensive evaluation]
⊚: Adhesive strength determination, position adjustment over time, and separator appearance are all ◯.
◯: The appearance of the separator is ◯, and one or more of the adhesive force determination and the temporal position adjustment are Δ.
x: x is included in any one of the three items.

Components and materials used in each example and comparative example are as follows.
(Composition of adhesive layer)

* Each component in Table 1 is as follows.
Olefin polymer: trade name "L-1253", manufactured by Kuraray Co., Ltd., hydrogenated polybutadiene tackifying resin 1 having a (meth)acryloyl group at one end: trade name "Arcon P140", manufactured by Arakawa Chemical Industries, Ltd., water Additive petroleum resin, softening point 140°C
Tackifier resin 2: trade name “Arcon P100”, manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point 100 ° C.
Fine particles: trade name “Celstar Z-27” manufactured by Tokai Kogyo Co., Ltd. Glass balloon Cross-linking agent: trade name “TEAI-1000” manufactured by Nippon Soda Co., Ltd. Polymerization initiator: 2,2-dimethoxy-2-phenylacetophenone

(separator)
Each raw material shown in Table 2 was mixed in a predetermined composition shown in Table 3, extruded into a sheet shape and molded. 1 to No. 5 separators were obtained. No. 1 to No. 5 had a thickness of 50 μm. Also, No. 6 to No. 8 separators were as follows.
No. 6: Toyo Cloth Co., Ltd., trade name "CPP Separator #60", single-sided peeling No. 7: Lintec Co., release paper, product name "KA-4G", single-sided release treatment No. 8: Polyethylene terephthalate with release treatment on one side with silicone resin (trade name “PET-O3-BU”, manufactured by Mitsui Chemicals Tohcello)

※表面改質剤含有マスターバッチは、表面改質剤の含有量が３０質量％である。

* The surface modifier-containing masterbatch has a surface modifier content of 30% by mass.

(masking member)
R03650: JX ANCI company Conwet net, product number "R03650"
R03235: JX ANCI company Conwet net, product number "R03235"
R07107: JX ANCI company Conwet net, product number "R07107"
R06200: JX ANCI company Conwet net, part number "R06200"
X06065: JX ANCI company Conwet net, product number "X06065"

[Example 1]
A pressure-sensitive adhesive composition was prepared according to the formulation shown in Table 1. The adhesive composition was purged with nitrogen to remove dissolved oxygen. Next, a spacer having a thickness of 900 μm was placed on the release-treated surface of the separator, and the pressure-sensitive adhesive composition was applied onto the release-treated surface of the separator. Next, another separator was coated on the applied pressure-sensitive adhesive composition so that the release-treated surface was in contact with the pressure-sensitive adhesive composition. As the separator, a PET film (thickness: 50 μm) subjected to silicone release treatment was used.
In this state, the intensity of the chemical lamp was adjusted so that the ultraviolet irradiation intensity on the separator on the coated side was 5 mW/cm ² , and ultraviolet irradiation was performed for 15 minutes to obtain a pressure-sensitive adhesive layer with separators attached on both sides. The adhesive layer had a thickness of 900 μm and a gel fraction of 64.4%.
After that, one separator was peeled off, and the mesh material and separator shown in Table 4 were sequentially laminated on the adhesive layer, and the pressure was 0 against a sample width of 500 mm under an environment of 23 ° C. and 50% RH with a laminator. A pressure of 0.5 MPa was applied to obtain a solid adhesive in which an adhesive layer, a mesh material, and a separator were laminated in this order on the separator.

[Examples 2 to 9, Examples 11 to 13, Comparative Examples 1 to 6]
It was carried out in the same manner as in Example 1, except that the thickness of the pressure-sensitive adhesive layer, the mesh material to be used, and the type of separator were changed as shown in Table 4. The thickness of the adhesive layer was adjusted by changing the thickness of the spacer to be used according to the thickness of the adhesive layer.
Moreover, in Example 2, two mesh materials shown in Table 4 were laminated on the pressure-sensitive adhesive layer so that the intersection points of the spikes did not overlap each other.

[Example 10]
The procedure was carried out in the same manner as in Example 1, except that the amount of TEA-1000 (crosslinking agent) in the adhesive composition was changed to 2.0 parts by mass.

As described above, the solid adhesive of each example has the masking member coverage, the ratio of the maximum thickness of the masking member to the thickness of the pressure-sensitive adhesive layer (D1/D2), the load when the separator is stretched at 2%, and the masking member - By adjusting the height difference of the adhesive layer within a predetermined range, the adhesive strength of the adhesive layer was appropriately adjusted, and the position adjustment function could be sufficiently exhibited even after long-term storage.

REFERENCE SIGNS LIST 10 solid adhesive 11 adhesive layer 11A one surface 11B other surface 12 masking member 12A, 12B linear member 12C spike portion D1 maximum thickness of masking member D2 thickness of adhesive layer T height difference

Claims (4)

An adhesive layer, a masking member provided on at least one surface of the adhesive layer, and a separator provided on the one surface of the adhesive layer so as to cover the masking member,
The masking member is composed of a thread-like or strip-like member and has a spike portion, the thickness of the apex of the spike portion being the maximum thickness,
The masking member has a coverage of less than 20% with respect to the one surface of the pressure-sensitive adhesive layer, and the maximum thickness of the masking member is 6 to 70% of the thickness of the pressure-sensitive adhesive layer,
The separator has a load at 2% elongation of 42.7 N/24 mm or less, and in a cross section passing through two vertices of adjacent spikes of the masking member, a straight line connecting two vertices of the spikes and the vertices The height difference between the two points and the one surface of the pressure-sensitive adhesive layer is 70 μm or more,
A solid adhesive, wherein the pressure-sensitive adhesive layer has a storage modulus of 1.0×10 ⁵ Pa or more and 5.0×10 ⁸ Pa or less at 0 to 50°C. 2. The solid adhesive according to claim 1, wherein the pressure-sensitive adhesive layer on the one surface provided with the masking member has an adhesive strength retention rate of 30% or more. 3. The solid adhesive according to claim 1, which is in the form of a sheet or a roll. 4. The solid adhesive according to claim 3 , wherein in the rolled solid adhesive, the breaking elongation of the separator is 8% or more.

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