JP6723144B2 - Flame-retardant tape and method for producing flame-retardant tape - Google Patents

Description

The present invention relates to a flame-retardant tape or the like. More specifically, the present invention relates to a flame-retardant tape or the like attached to the outer surface of a battery or the like.

In recent years, for example, safety has been improved by attaching a flame-retardant tape as an exterior of a battery cell used in a vehicle-mounted lithium-ion battery.
In the flammability test of a plastic material such as a flame-retardant tape, the UL510 standard is used worldwide as one of the standards representing the degree of flame resistance. Further, in recent years, a flame-retardant adhesive tape conforming to a higher standard, UL-94 standard, for the purpose of preventing flame retardation when a high-capacity and high-density battery generates heat, and preventing spread of fire in a building fire. Is desired.
Further, there is an increasing demand for so-called non-halogen flame-retardant tapes that do not use materials containing halogen atoms in order to suppress the generation of toxic gases during combustion.

In Patent Document 1, a halogen-free flame-retardant adhesive layer is provided on one surface of a halogen-free base film, while a non-halogen flame-retardant ink coating layer is provided on the surface of the base film opposite to the flame-retardant adhesive layer. A halogen-free flame-retardant tape provided with is disclosed.
Further, in Patent Document 2, on at least one surface of the substrate, with respect to 100 parts by mass of the adhesive base polymer, neither a halogen compound nor an antimony compound is intentionally added, and a phosphoric acid ester flame retardant 20 to 300 parts by mass. And a pressure-sensitive adhesive layer made of a flame-retardant pressure-sensitive adhesive composition containing 5 to 50 parts by mass of an aromatic-containing tackifying resin are disclosed.

JP, 2003-62937, A JP, 2006-219565, A

In the flame-retardant tape, a flame-retardant agent such as a flame-retardant filler may be included in the flame-retardant adhesive layer in order to improve flame retardancy. However, in order to impart sufficient flame retardancy to the flame-retardant tape, it is necessary to include many flame retardants, and there is a problem in that the tackiness decreases.
It is an object of the present invention to provide a flame-retardant tape that retains flame retardancy and is less likely to have reduced adhesiveness.

The flame-retardant tape of the present invention comprises a base material having a thickness of 12 μm or more and 100 μm or less, a flame-retardant adhesive layer containing a flame retardant provided on one surface side of the base material, and the other surface side of the base material. And a flame-retardant layer containing a phosphorus-modified resin as a main component, wherein the flame-retardant adhesive layer contains 16.0 parts by mass or more and 48.0 parts by mass or more of the flame retardant when the flame-retardant adhesive layer is 100 parts by mass. The content of the flame-retardant layer is 5.0 parts by mass or more and 10.0 parts by mass or less as a phosphorus atom when the phosphorus-modified resin is 100 parts by mass, and the thickness is 0.50 times or more of the base material. It is characterized by

Here, the flame retardant preferably includes a phosphorus compound, and the flame retardant can include a phosphorus-modified resin.

The phosphorus-modified resin is preferably a phosphorus-containing acrylic resin, and the phosphorus-containing acrylic resin may be a methacrylic acid ester-based resin whose side chain is modified with a phosphoric acid group.

Further, the adhesive layer preferably has a thickness of 20 μm or more.
Furthermore, an anchor coat layer can be further provided between the substrate and the flame-retardant adhesive layer.

Further, the method for producing a flame-retardant tape of the present invention comprises a substrate preparing step of preparing a substrate having a thickness of 12 μm or more and 100 μm or less, and a flame-retardant adhesive layer containing a flame retardant on one surface side of the substrate. A flame-retardant pressure-sensitive adhesive layer forming step, including a flame-retardant layer forming step of forming a flame-retardant layer containing a phosphorus-modified resin as a main component on the other surface side of the substrate. A flame-retardant adhesive layer containing 16.0 parts by mass or more and 48.0 parts by mass or less of a flame-retardant when 100 parts by mass of the flame-retardant adhesive layer is used, and 100 parts by mass of the phosphorus-modified resin is used in the flame-retardant layer forming step. It is characterized by forming a flame-retardant layer containing not less than 5.0 parts by mass and not more than 10.0 parts by mass as a phosphorus atom, and having a thickness of 0.50 times or more that of the base material.

An anchor coat layer forming step of forming an anchor coat layer on the base material may be further included after the base material preparing step and before the flame-retardant adhesive layer forming step.

According to the present invention, it is possible to provide a flame-retardant tape or the like that retains flame retardancy and is unlikely to have reduced adhesiveness.

(A) is sectional drawing shown about the 1st example of the flame-retardant tape to which this Embodiment is applied. (B) is sectional drawing shown about the 2nd example of the flame-retardant tape to which this Embodiment is applied. It is a flowchart explaining the manufacturing method of a flame-retardant tape.

Hereinafter, modes for carrying out the present invention will be described in detail. The present invention is not limited to the embodiments below. Further, various modifications can be carried out within the scope of the gist. Furthermore, the drawings used are for explaining the present embodiment, and do not represent the actual size.

<Explanation of the overall structure of the flame-retardant tape>
FIG. 1A is a cross-sectional view showing a first example of a flame-retardant tape to which this embodiment is applied. Further, FIG. 1B is a cross-sectional view showing a second example of the flame-retardant tape to which this embodiment is applied.
The flame-retardant tape 1 illustrated in FIG. 1A includes a base material 2, a flame-retardant adhesive layer 3 provided on one surface side of the base material 2, and a flame-retardant flame provided on the other surface side of the base material 2. And layer 4. The flame-retardant tape 1 shown in FIG. 1(b) has a base material 2, a flame-retardant adhesive layer 3 and a flame-retardant layer 4, and an anchor coat layer 5 between the base material 2 and the flame-retardant adhesive layer 3. Prepare Although not shown, in FIGS. 1A and 1B, a release liner or the like may be provided on the surface side (one surface side) of the flame-retardant adhesive layer 3 opposite to the base material 2. ..

The flame-retardant tape 1 is required to be flame-retardant so that an adherend such as a vehicle-mounted lithium-ion battery to which the flame-retardant tape 1 is attached secures safety during heat generation. Further, it preferably has electrical insulation. For flame retardancy, it is necessary to pass UL510, which is a standard indicating the degree of flame resistance. As the electrical insulation, it is preferable to maintain the insulation at a voltage of 3.0 kV or more. In addition, it may be required that the removability is good, that it is black, and that it has an appearance that is free from spots.

<Substrate>
The base material 2 serves as a support for forming the flame-retardant adhesive layer 3, the flame-retardant layer 4, and the anchor coat layer 5. Further, the base material 2 is required to have a function of ensuring the mechanical strength of the flame-retardant tape 1 as a whole, and flexibly changes its shape by following the irregularities and curved surfaces of the adherend to which the flame-retardant tape 1 is attached. A function that can do is required. When the flame-retardant tape 1 is required to have electrical insulation, the base material 2 also needs to have electrical insulation.

If such conditions are satisfied, the material used for the base material 2 is not particularly limited, but a resin material can be more preferably used. Examples of the resin material include polyester, polypropylene, polyethylene, polyphenylene sulfide, polyimide, polyamide, polyacetate, and polyether ether ketone. Above all, in the present embodiment, for example, polyester can be preferably used. Examples of polyesters include polyethylene terephthalate (PET), polytrimethylene terephtalate (PTT), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN). it can. Above all, in the present embodiment, polyethylene terephthalate (PET) can be used more suitably.

The base material 2 preferably has a thickness of 12 μm or more and 100 μm or less. If the thickness of the base material 2 is less than 12 μm, it becomes difficult to secure the mechanical strength of the flame-retardant tape 1. As a result, the flame-retardant tape 1 is likely to be wrinkled. When the thickness of the base material 2 exceeds 100 μm, the followability to the irregularities and curved surfaces of the adherend on which the flame-retardant tape 1 is attached decreases, and the flame-retardant tape 1 is attached according to the shape of the adherend. Becomes difficult. Furthermore, since the base material 2 is not flame-retardant, the flame-retardant property of the flame-retardant tape 1 is likely to decrease. From the viewpoint of electrical insulation, the thickness of the base material 2 is preferably 25 μm or more. When the thickness of the base material 2 is 25 μm or more, it becomes easy to maintain the insulation even at a voltage of 3.0 kV or more. From the viewpoint of electrical insulation, the thickness of the base material 2 is more preferably 30 μm or more.

<Flame-retardant adhesive layer>
The flame-retardant adhesive layer 3 is a functional layer that has adhesiveness and exerts an adhesive force between the flame-retardant tape 1 and the adherend. The flame-retardant adhesive layer 3 is a functional layer that imparts flame retardancy to the flame-retardant tape 1. The flame-retardant adhesive layer 3 has a structure in which a flame retardant and a tackifier are dispersed in the main component.

The flame retardant imparts flame retardancy to the flame retardant tape 1. In the present embodiment, the flame retardant is a flame retardant filler. That is, the flame retardant is dispersed in the flame retardant adhesive layer 3 in the form of fine particles. In this case, the flame retardant preferably contains at least one selected from hydroxides, phosphorus compounds, melamine compounds, triazine compounds, guanidine compounds, guanylurea compounds, dicyandiamide, and boric acid compounds. By using such a flame retardant, it is possible to prevent the flame retardant from bleeding out from the flame retardant adhesive layer 3. Further, a phosphorus-modified resin described later may be included as a flame retardant.

Examples of the flame retardant of hydroxide include metal hydroxide. Specifically, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, etc. can be mentioned.
When the flame retardant is a hydroxide, the flame retardancy can be improved by causing an endothermic dehydration reaction with heating and cooling.

Examples of the phosphorus compound flame retardant include phosphoric acid ester-based flame retardants. Specific examples include aliphatic phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate and the like. In addition, melamine polyphosphate, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, trixylenyl phosphate, cresyl 2,6 xylenyl phosphate, tris(t-butylated phenyl) phosphate, tris(isopropylated phenyl) ) Aromatic phosphates such as phosphates and triaryl isopropyl phosphates can be mentioned. Furthermore, aromatic condensed phosphoric acid esters such as resorcinol bisdiphenyl phosphate, bisphenol A bis(diphenyl phosphate), resorcinol bisdixylenyl phosphate and the like can be mentioned.
When the flame retardant is a phosphorus compound, the flame retardancy can be improved by forming a nonflammable film by heating and blocking the inflow of oxygen. Further, it is preferable in that the production of solid residue is increased when the flame-retardant tape 1 is melted by heating and the production amount of the combustible gas is reduced to improve the flame retardancy.

In the present embodiment, aluminum hydroxide or melamine polyphosphate can be particularly preferably used as the flame retardant.

The tackifier imparts tackiness to the flame-retardant adhesive layer 3. The tackifier is not particularly limited, styrene resin, xylene resin, aromatic modified terpene resin, terpene phenol resin, aromatic petroleum resin, aliphatic aromatic petroleum resin, coumarone indene resin, Phenolic resins, disproportionated rosin resins, rosin-modified phenolic resins and the like can be used.
In the present embodiment, a terpene phenol resin can be particularly preferably used as the tackifier.

The main component is a binder that holds and disperses the flame retardant and the tackifier. As the main agent, for example, an acrylic adhesive or a rubber adhesive can be used.

The acrylic pressure-sensitive adhesive is obtained by copolymerizing a (meth)acrylic acid ester monomer. Examples of the (meth)acrylic acid ester monomer include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. And (meth)acrylic acid ester monomers such as isooctyl (meth)acrylate, nonyl (meth)acrylate, and isononyl (meth)acrylate. In addition, a monomer containing a functional group such as (meth)acrylic acid ester, (meth)acrylic acid, crotonic acid, fumaric acid, itaconic acid, (anhydrous)maleic acid, vinyl acetate, acrylonitrile, styrene, (meth)acrylic acid 2 -Hydroxyethyl, 2-methylolethylacrylamide, etc. may be added and copolymerized.

The rubber-based pressure-sensitive adhesive can be produced by mixing the elastomer component and the tackifying component. Examples of the elastomer component include natural rubber, styrene-butadiene rubber, butyl rubber, isoprene rubber, butadiene rubber, and styrene-isoprene block copolymer. The tackifying component is a rosin resin, a terpene resin, an aliphatic petroleum resin, an aromatic petroleum resin, a copolymer petroleum resin, an alicyclic petroleum resin, a coumarone/indene resin, a pure/monomer resin, Examples include phenolic resins and xylene resins.

In the present embodiment, an acrylic pressure-sensitive adhesive can be particularly preferably used as the main component.

The flame-retardant adhesive layer 3 may include a coloring agent for making the flame-retardant tape 1 black. As the colorant, for example, carbon black can be used.

The flame-retardant adhesive layer 3 preferably contains 16.0 parts by mass or more and 48.0 parts by mass or less of the flame retardant when the flame-retardant adhesive layer 3 is 100 parts by mass. When the amount of the flame retardant is less than 16.0 parts by mass, the flame retardancy of the flame retardant tape 1 is likely to decrease. Further, when the flame retardant exceeds 48.0 parts by mass, the adhesiveness of the flame-retardant adhesive layer 3 is likely to be reduced, and as a result, the adhesive force of the flame-retardant tape 1 is likely to be reduced. That is, within the above range, it is possible to achieve both flame retardancy and tackiness. The amount of the flame retardant is more preferably 18.5 parts by mass or more and 34.5 parts by mass or less.
The flame-retardant adhesive layer 3 preferably has a thickness of 20 μm or more. When the thickness is less than 20 μm, the adhesiveness is reduced, and the adhesive strength of the flame-retardant tape 1 is likely to be reduced.

The adhesive strength of the flame-retardant adhesive layer 3 to alumite is preferably 1.5 N/10 mm or more, more preferably 2.5 N/10 mm or more. If the adhesive strength is less than 1.5 N/10 mm, the flame-retardant tape 1 is likely to be displaced or peeled off from the adherend.

<Flame retardant layer>
The flame-retardant layer 4, together with the flame-retardant adhesive layer 3, is a functional layer that imparts flame retardancy to the flame-retardant tape 1. That is, in the conventional form in which the flame retardant adhesive layer 3 contains a flame retardant, a large amount of the flame retardant is required to impart flame retardancy, and in that case, there is a problem that the adhesiveness is likely to decrease. Was there. In the present embodiment, by providing the flame-retardant layer 4 in addition to the flame-retardant adhesive layer 3, the amount of the flame-retardant contained in the flame-retardant adhesive layer 3 is reduced, thereby suppressing the decrease in adhesiveness. ..

The flame-retardant layer 4 has a phosphorus-modified resin as a main component. The phosphorus-modified resin is preferably, for example, a phosphorus-containing acrylic resin. More specifically, the phosphorus-modified resin is, for example, a specially modified methacrylic acid ester-based resin. This is a methacrylic acid ester-based resin whose side chain is modified with a phosphoric acid group. The phosphorus-modified resin is, for example, a phosphorus skeleton polyester resin.

Further, the flame-retardant layer 4 contains 5.0 parts by mass or more and 10.0 parts by mass or less as a phosphorus atom when the phosphorus-modified resin is 100 parts by mass. Further, when the phosphorus-modified resin is 100 parts by mass, it is more preferable to contain 5.0 parts by mass or more and 8.0 parts by mass or less as a phosphorus atom. When the amount of phosphorus atoms is less than 5.0 parts by mass, the flame retardancy of the flame-retardant tape 1 is likely to decrease. Further, it is difficult to include more than 10.0 parts by mass as a phosphorus atom in the phosphorus-modified resin.

In the case of the phosphorus-modified resin, as in the case of the phosphorus compound flame retardant, a flame-retardant property can be improved by forming an incombustible film by heating and blocking the inflow of oxygen. Further, when the flame-retardant tape 1 is melted by heating, the production of solid residue is increased, and the production amount of combustible gas is reduced, whereby the flame retardancy can be improved.

As the specially modified methacrylic acid ester-based resin that satisfies such conditions, for example, Kogham HW-500 (trade name) manufactured by Showa Denko KK can be used. As the phosphorus skeleton polyester resin satisfying such a condition, for example, Pluscoat Z-900 (trade name) manufactured by Gosho Chemical Industry Co., Ltd. can be used.

The flame-retardant layer 4 preferably has a thickness of 0.50 times or more that of the base material 2. When the thickness of the flame-retardant layer 4 is less than 0.5 times the thickness of the base material 2, the flame-retardant property tends to decrease. From the viewpoint of flame retardancy, the thickness of the flame-retardant layer 4 is preferably 1.00 times or more, more preferably 2.10 times or more the thickness of the base material 2.

The flame-retardant layer 4 has a thickening agent for improving the coating property when applying a solution for a flame-retardant layer, which is a coating liquid described later, and a defoaming agent for suppressing foaming and suppressing rough appearance. The agent may be further included.

<Anchor coat layer>
The anchor coat layer 5 is a functional layer for improving the adhesion between the base material 2 and the flame-retardant adhesive layer 3.
Examples of materials used for the anchor coat layer 5 include polyester/polyurethane resin, methacrylic resin, acrylic resin, polyester resin, polystyrene resin, polyurethane resin, epoxy resin, and phenol resin. Among them, polyester/polyurethane resin is preferable from the viewpoint of adhesion.

<Method of manufacturing flame-retardant tape>
FIG. 2 is a flowchart illustrating the method for manufacturing the flame-retardant tape 1.
Note that FIG. 2 shows a manufacturing method for the flame-retardant tape 1 including the anchor coat layer 5 shown in FIG.
First, a base material having a thickness of 12 μm or more and 100 μm or less is prepared (step 101: base material preparation process).

Next, a flame retardant layer solution for applying the flame retardant layer 4 is prepared (step 102).
Then, the flame-retardant layer solution is used to form the flame-retardant layer 4 containing phosphorus-modified resin as a main component on the base material 2 (step 103: flame-retardant layer forming step). That is, the flame-retardant layer 4 is formed by applying the solution for the flame-retardant layer and drying the coating film formed thereby.

Next, an anchor coat layer solution for applying the anchor coat layer 5 is prepared (step 104).
Then, the anchor coat layer solution is used to form the anchor coat layer 5 on the side of the base material 2 opposite to the side on which the flame retardant layer 4 is formed (step 105: anchor coat layer forming step). That is, the anchor coat layer 5 is formed by applying the anchor coat layer solution and drying the coating film formed thereby. The anchor coat layer forming step is after the base material preparing step and before the flame retardant adhesive layer forming step.

Next, a flame-retardant adhesive layer solution for applying the flame-retardant adhesive layer 3 is prepared (step 106).
Then, the flame-retardant adhesive layer solution is used to form the flame-retardant adhesive layer 3 containing the flame retardant on the anchor coat layer 5 (step 107: flame-retardant adhesive layer forming step). That is, the flame-retardant adhesive layer 3 is formed by applying the flame-retardant adhesive layer solution and drying the coating film formed thereby.
The flame-retardant tape 1 can be manufactured by the above steps.

According to the present embodiment described in detail above, not only a flame retardant is added to the flame-retardant adhesive layer 3 to impart flame retardancy, but the flame-retardant layer 4 is provided and phosphorus-modified to impart flame retardancy thereto. Flame retardancy is improved by including a predetermined amount of resin. As a result, it is possible to reduce the amount of the flame retardant added to the flame-retardant adhesive layer 3, and it is possible to provide the flame-retardant tape 1 in which the adhesiveness is less likely to decrease while maintaining the flame retardancy. Further, since the flame-retardant tape 1 of the present embodiment does not contain halogen, it is possible to suppress the generation of harmful gas even if, for example, combustion occurs.

Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples unless it exceeds the gist.

The flame-retardant tape 1 having the anchor coat layer 5 shown in FIG. 1(b) was prepared and evaluated.
[Creation of flame-retardant tape 1]
(Example 1)
In this example, a polyethylene terephthalate (PET) film having a thickness of 25 μm was used as the base material 2.

Then, the flame-retardant layer 4 was formed on one surface side of the base material 2 as follows.
First, distilled water was used as a solvent, and Kogama HW-500 (trade name) manufactured by Showa Denko KK as a phosphorus-modified resin was dissolved in this solvent. Further, as a thickener, Juliamer AC-10SH (trade name) manufactured by Toagosei Co., Ltd. was used, and 2.8 parts by mass was added to 100 parts by mass of cog HW-500 to prepare a solution for a flame retardant layer. .. Then, the flame-retardant layer solution was applied to one side of the substrate 2 and dried to form the flame-retardant layer 4.
At this time, the flame-retardant layer 4 was made to contain 8.0 parts by mass as a phosphorus atom when the phosphorus-modified resin was 100 parts by mass. The thickness of the flame-retardant layer 4 was 0.52 times that of the base material 2 and was 13 μm.

Next, the anchor coat layer 5 was formed on the other surface side of the base material 2 as follows.
First, using toluene as a solvent, the polyester/polyurethane resin was dissolved to prepare an anchor coat layer solution. As the polyester/polyurethane resin, Seika Bond E-292 (trade name) manufactured by Dainichi Seika Kogyo Co., Ltd. was used, and Seica Bond C-75N-1.5 (trade name) was used as the curing agent. Then, an anchor coat layer solution was applied to the other side of the base material 2 and dried to form an anchor coat layer 5. Here, the thickness of the anchor coat layer 5 was set to about 0.1 μm.

Further, the flame-retardant adhesive layer 3 was formed on the other surface side of the anchor coat layer 5 as follows.
Here, ethyl acetate was used as the solvent, and aluminum hydroxide and melamine polyphosphate were added to this solvent as flame retardants. Carbon black was added as a colorant. Further, a terpene phenol resin as a tackifier and an acrylic pressure sensitive adhesive as a main component were dissolved in this solvent. Then, the above components were stirred and dispersed in the solvent to prepare a flame retardant adhesive layer solution.

At this time, as the aluminum hydroxide as a flame retardant, Heidilite H42STV (trade name) manufactured by Showa Denko KK was used. As melamine polyphosphate which is a flame retardant, Phosmel 200FINE (trade name) manufactured by Nissan Chemical Industries, Ltd. was used. MA220 (trade name) manufactured by Mitsubishi Chemical Corporation was used as carbon black as a colorant. And these were made to be 15.6 mass %, 16.5 mass %, and 2.2 mass %, respectively, so that a total of 34.3 mass %.
Further, YS Polystar K-125 (trade name) manufactured by Yasuhara Chemical Co., Ltd. was used as a terpene phenol resin as a tackifier. Further, as the acrylic adhesive as the main agent, SK Dyne 1633H (trade name) manufactured by Soken Chemical Industry Co., Ltd. was used. These were made to be 4.3% by mass and 61.4% by mass, respectively, to make a total of 65.7% by mass.

Then, the flame-retardant adhesive layer solution was applied to the other surface side of the anchor coat layer 5 and dried to form the flame-retardant adhesive layer 3.
At this time, the flame-retardant adhesive layer 3 contained 34.3 parts by mass of the flame retardant when the flame-retardant adhesive layer 3 was 100 parts by mass. The thickness of the flame-retardant adhesive layer 3 was 30 μm.

The flame-retardant tape 1 of this example was produced by the above steps.

(Examples 2 to 8)
A flame-retardant tape 1 was prepared in the same manner as in Example 1 except that the changes were made as shown in Table 1 with respect to Example 1. The flame-retardant tape 1 of Example 8 does not have the anchor coat layer 5 and is of the type shown in FIG.

(Comparative Examples 1 to 4)
A flame-retardant tape was prepared in the same manner as in Example 1 except that the changes were made as shown in Table 1 with respect to Example 1. Among them, in Comparative Example 1, the amount of phosphorus atoms contained in the flame-retardant layer 4 is 4.0 parts by mass, which is less than the lower limit value of 5.0 parts by mass. In Comparative Example 2, the thickness of the flame-retardant layer 4 is 0.34 times, which is less than the lower limit of 0.50 times that of the base material 2. Furthermore, in Comparative Example 3, the amount of the flame retardant in the flame-retardant adhesive layer 3 is 15.4 parts by mass, which is below the lower limit of 16.0 parts by mass. Further, in Comparative Example 4, the amount of the flame retardant in the flame-retardant adhesive layer 3 is 49.6 parts by mass, which exceeds the upper limit value of 48.0 parts by mass.

〔Evaluation method〕
As a flammability test, the flame-retardant tapes 1 of Examples 1 to 8 and Comparative Examples 1 to 4 were evaluated based on UL510 standard.
The adhesive strength was also evaluated. As the adhesive force, the adhesive force (N/10 mm) to the alumite plate was measured according to the method described in JIS Z 0237. The measurement temperature was 23°C.

〔Evaluation results〕
The evaluation results are shown in Table 1.
The flame-retardant tapes 1 of Examples 1 to 8 all passed the flammability test. Also, the adhesive strength was 1.5 N/10 mm or more, which was good.
On the other hand, the flame-retardant tapes 1 of Comparative Examples 1 to 3 all failed the flammability test.
In the flame-retardant tape 1 of Comparative Example 1, since the amount of phosphorus atoms in the phosphorus-modified resin contained in the flame-retardant layer 4 was as small as 4.0 parts by mass, the flame retardancy was lowered, and as a result, the flammability test failed. Became.
In the flame-retardant tape 1 of Comparative Example 2, the thickness of the flame-retardant layer 4 was 0.34 with respect to the base material 2, and the flame-retardant layer 4 was thin, so that the flame-retardant property was reduced, resulting in combustion. The sexuality test failed.
In the flame-retardant tape 1 of Comparative Example 3, since the amount of the flame-retardant in the flame-retardant adhesive layer 3 was as small as 15.4 mass %, the flame retardancy was lowered, and as a result, the flammability test failed.
The flame-retardant tape 1 of Comparative Example 4 passed the flammability test, but the adhesive strength was insufficient. In other words, too much flame retardant resulted in insufficient adhesive strength.
According to the results of Examples 1 to 8 and Comparative Examples 1 to 4, the amount of phosphorus atoms in the flame-retardant layer 4, the thickness of the flame-retardant layer 4, and the amount of the flame-retardant added in the flame-retardant adhesive layer 3 were within the ranges described above. It was confirmed that it was necessary to be.

1... Flame-retardant tape, 2... Base material, 3... Flame-retardant adhesive layer, 4... Flame-retardant layer, 5... Anchor coat layer

Claims (9)

A substrate having a thickness of 12 μm or more and 100 μm or less,
A flame-retardant adhesive layer provided on one surface side of the base material and containing a flame retardant,
Provided on the other surface side of the substrate, a flame-retardant layer containing a phosphorus-modified resin as a main component,
Equipped with
The flame-retardant adhesive layer contains 16.0 parts by mass or more and 48.0 parts by mass or less of the flame retardant when the flame-retardant adhesive layer is 100 parts by mass,
The flame-retardant layer contains 5.0 parts by mass or more and 10.0 parts by mass or less as a phosphorus atom when the phosphorus-modified resin is 100 parts by mass, and has a thickness of 0.50 times or more that of the base material. Flame-retardant tape. The flame retardant tape according to claim 1, wherein the flame retardant contains a phosphorus compound. The flame retardant tape according to claim 1, wherein the flame retardant contains a phosphorus-modified resin. The flame-retardant tape according to any one of claims 1 to 3, wherein the phosphorus-modified resin is a phosphorus-containing acrylic resin. The flame-retardant tape according to claim 4, wherein the phosphorus-containing acrylic resin is one obtained by modifying a side chain of a methacrylic acid ester resin with a phosphoric acid group. 6. The flame-retardant tape according to claim 1, wherein the flame-retardant adhesive layer has a thickness of 20 μm or more. The flame-retardant tape according to any one of claims 1 to 6, further comprising an anchor coat layer between the base material and the flame-retardant adhesive layer. A base material preparing step of preparing a base material having a thickness of 12 μm or more and 100 μm or less;
On one surface side of the base material, a flame-retardant adhesive layer forming step of forming a flame-retardant adhesive layer containing a flame retardant,
On the other surface side of the base material, a flame-retardant layer forming step of forming a flame-retardant layer containing a phosphorus-modified resin as a main component,
Including
The flame-retardant adhesive layer forming step forms the flame-retardant adhesive layer containing 16.0 parts by mass or more and 48.0 parts by mass or less of the flame retardant when the flame-retardant adhesive layer is 100 parts by mass,
The flame-retardant layer forming step includes 5.0 parts by mass or more and 10.0 parts by mass or less as a phosphorus atom when the phosphorus-modified resin is 100 parts by mass, and has a thickness of 0.50 times or more that of the base material. A method for producing a flame-retardant tape, wherein the flame-retardant layer is formed. The anchor coat layer forming step of forming an anchor coat layer on the base material after the base material preparing step and before the flame retardant adhesive layer forming step is further included. Of manufacturing flame-retardant tape.

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