JP2018083904A - Flame-retardant tape and production method of flame-retardant tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant tape which maintains flame retardancy while the tackiness of which hardly degrades.SOLUTION: A flame-retardant tape 1 is provided which comprises: a substrate 2 having a thickness of 12 μm or more and 100 μm or low; a flame retardant pressure-sensitive adhesive layer 3 provided on one front surface side of the substrate 2 and containing a flame retardant; and a flame retardant layer 4 provided on the other front surface side of the substrate 2 and having a phosphorus-modified resin as a main component, and in which the flame-retardant pressure-sensitive adhesive layer 3 contains the flame retardant of 16.0 pts.mass or larger and 48.0 pts.mass or smaller relative to 100 pts.mass of the flame retardant, and the flame retardant layer 4 contains phosphorus atoms of 5.0 pts.mass or larger and 10.0 pts.mass or smaller relative to 100 pts.mass of the phosphorus-modified resin, and has a thickness 0.50 times or more larger than the substrate.SELECTED DRAWING: Figure 1

Description

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

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

In Patent Document 1, a non-halogen flame retardant adhesive layer is provided on one side of a non-halogen 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 non-halogen flame retardant tape is provided.
Moreover, in patent document 2, neither a halogen compound nor an antimony compound is added intentionally with respect to 100 mass parts of adhesive base polymers on at least one surface of a base material, Phosphate ester flame retardant 20-300 mass And a flame-retardant pressure-sensitive adhesive tape provided with a pressure-sensitive adhesive layer comprising a flame-retardant pressure-sensitive adhesive composition to which 5 to 50 parts by mass of an aromatic-containing tackifying resin is added.

JP 2003-62937 A JP 2006-219565 A

In the flame retardant tape, a flame retardant 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 that the adhesiveness is lowered.
An object of the present invention is to provide a flame retardant tape that maintains flame retardancy and is less susceptible to lowering of adhesiveness.

  The flame-retardant tape of the present invention is provided on a substrate having a thickness of 12 μm or more and 100 μm or less, on one surface side of the substrate, on a flame-retardant adhesive layer containing a flame retardant, and on the other surface side of the substrate. A flame retardant layer comprising a phosphorus-modified resin as a main component, and the flame retardant adhesive layer comprises 16.0 parts by mass or more and 48.0 parts by mass of a 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 phosphorus atoms when the phosphorus-modified resin is 100 parts by mass, and the thickness is 0.50 or more times that of the substrate. It is characterized by being.

  Here, the flame retardant preferably contains a phosphorus compound, and the flame retardant can contain a phosphorus-modified resin.

  The phosphorus-modified resin is preferably a phosphorus-containing acrylic resin, and the phosphorus-containing acrylic resin can be obtained by modifying the side chain of the methacrylic ester resin with a phosphate group.

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

  Moreover, the manufacturing method of the flame retardant tape of the present invention includes a substrate preparation 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 adhesive layer forming step, and a flame retardant layer forming step of forming a flame retardant layer mainly composed of a phosphorus-modified resin on the other surface side of the base material. 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 is formed. In addition, it is characterized in that a flame retardant layer containing 5.0 parts by mass or more and 10.0 parts by mass or less as phosphorus atoms and having a thickness of 0.50 times or more that of the substrate is formed.

  Here, an anchor coat layer forming step of forming an anchor coat layer on the substrate can be further included after the base material preparing step and before the flame retardant adhesive layer forming step.

  ADVANTAGE OF THE INVENTION According to this invention, a flame-retardant tape etc. which are hard to reduce adhesiveness can be provided, maintaining a flame retardance.

(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 the flowchart explaining the manufacturing method of a flame-retardant tape.

  Hereinafter, embodiments for carrying out the present invention will be described in detail. In addition, this invention is not limited to the following embodiment. Various modifications can be made within the scope of the gist. Further, the drawings to be used are for explaining the present embodiment and do not represent the actual size.

<Description of overall structure of flame retardant tape>
Fig.1 (a) is sectional drawing shown about the 1st example of the flame-retardant tape to which this Embodiment is applied. Moreover, FIG.1 (b) is sectional drawing shown about the 2nd 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 provided on the other surface side of the base material 2. Layer 4. Moreover, the flame retardant tape 1 illustrated in FIG. 1B includes an anchor coat layer 5 between the substrate 2 and the flame retardant adhesive layer 3 in addition to the substrate 2, the flame retardant adhesive layer 3, and the flame retardant layer 4. Prepare. Although not shown, in FIGS. 1A to 1B, a release liner or the like may be provided on the surface side (one surface side) opposite to the base material 2 of the flame retardant adhesive layer 3. .

  The flame retardant tape 1 is required to be flame retardant so that the adherend to which the flame retardant tape 1 such as an in-vehicle lithium ion battery is attached secures safety during heat generation. Moreover, it is preferable to have electrical insulation. As flame retardancy, it is necessary to pass UL510 which is a standard representing the degree of incombustibility. As the electrical insulation, it is preferable to maintain the insulation at a voltage of 3.0 kV or more, for example. In addition, it may be required to have good removability, be black, and have no external appearance.

<Base material>
The substrate 2 serves as a support for forming the flame retardant adhesive layer 3, the flame retardant layer 4, and the anchor coat layer 5. In addition, the base material 2 is required to have a function of ensuring the mechanical strength of the entire flame retardant tape 1, and also follows the unevenness and curved surface of the adherend to which the flame retardant tape 1 is attached, and flexibly changes its shape. Functions that can be done are required. Moreover, when electrical insulation is calculated | required by the flame-retardant tape 1, it is necessary for the base material 2 to also have electrical insulation.

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

  The substrate 2 preferably has a thickness of 12 μm or more and 100 μm or less. When the thickness of the base material 2 is less than 12 μm, it is difficult to ensure the mechanical strength of the flame retardant tape 1. As a result, wrinkles and the like are likely to occur in the flame retardant tape 1. Moreover, when the thickness of the base material 2 exceeds 100 μm, the followability to the unevenness and the curved surface of the adherend to which the flame retardant tape 1 is attached is lowered, and the flame retardant tape 1 is attached according to the shape of the adherend. It becomes difficult. Furthermore, since the base material 2 is not flame retardant, the flame retardancy of the flame retardant tape 1 is likely to decrease. From the viewpoint of electrical insulation, the thickness of the substrate 2 is preferably 25 μm or more. When the thickness of the substrate 2 is 25 μm or more, it is easy to maintain 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 having adhesiveness and exhibiting 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 configuration in which a flame retardant and a tackifier are dispersed in the main agent.

  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 setting it as such a flame retardant, it can suppress that a flame retardant bleeds out from the flame retardant adhesion layer 3. FIG. Moreover, the phosphorus modified resin mentioned later may be included as a flame retardant.

Examples of hydroxide flame retardants include metal hydroxides. Specific examples include aluminum hydroxide, magnesium hydroxide, calcium hydroxide and the like.
When the flame retardant is a hydroxide, flame retardancy can be improved by causing an endothermic dehydration reaction with heating and cooling.

Moreover, as a flame retardant of a phosphorus compound, a phosphate ester type thing is mentioned, for example. Specific examples include aliphatic phosphate esters such as trimethyl phosphate, triethyl phosphate, and tributyl phosphate. In addition, melamine polyphosphate, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, trixylenyl phosphate, cresyl 2, 6xylenyl phosphate, tris (t-butylated phenyl) phosphate, tris (isopropylated phenyl) ) Aromatic phosphates such as phosphates and triaryl isopropylates. Furthermore, aromatic condensed phosphate esters such as resorcinol bisdiphenyl phosphate, bisphenol A bis (diphenyl phosphate), and resorcinol bisdixylenyl phosphate can be used.
When the flame retardant is a phosphorus compound, the flame retardancy can be improved by forming a non-flammable film by heating and blocking the inflow of oxygen. Moreover, it is preferable at the point which can improve a flame retardance by increasing the production | generation of a solid residue when the flame retardant tape 1 fuse | melts by heating, and reducing the production amount of a combustible gas.

  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, Phenol resins, disproportionated rosin resins, rosin-modified phenol resins, and the like can be used.
In the present embodiment, a terpene phenol resin can be particularly preferably used as a tackifier.

  The main agent is a binder that is dispersed while holding a flame retardant and a 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) acrylate monomer include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. And (meth) acrylate monomers such as isooctyl (meth) acrylate, nonyl (meth) acrylate, and isononyl (meth) acrylate. (Meth) acrylic acid ester monomers containing functional groups such as (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 an elastomer component and a tackifier component. Examples of the elastomer component include natural rubber, styrene butadiene rubber, butyl rubber, isoprene rubber, butadiene rubber, and styrene / isoprene block copolymer. In addition, tackifying components include rosin resin, terpene resin, aliphatic petroleum resin, aromatic petroleum resin, copolymer petroleum resin, alicyclic petroleum resin, coumarone / indene resin, pure monomer resin, Examples thereof include phenolic resins and xylene resins.

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

  The flame retardant adhesive layer 3 may contain a colorant for making the flame retardant tape 1 black, for example. For example, carbon black can be used as the colorant.

The flame retardant adhesive layer 3 preferably contains 16.0 parts by mass or more and 48.0 parts by mass or less of a flame retardant when the flame retardant adhesive layer 3 is 100 parts by mass. If the flame retardant is less than 16.0 parts by mass, the flame retardancy of the flame retardant tape 1 tends to be reduced. Moreover, when a flame retardant exceeds 48.0 mass parts, the adhesiveness of the flame-resistant adhesion layer 3 will fall easily, As a result, the adhesive force of the flame-retardant tape 1 will fall easily. That is, if it is the said range, a flame retardance and adhesiveness can be made compatible. 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 lowered, and the adhesive strength of the flame retardant tape 1 is easily lowered.

  Moreover, it is preferable that the adhesive force with respect to the alumite of the flame-retardant adhesion layer 3 is 1.5 N / 10 mm or more, and it is still more preferable that it is 2.5 N / 10 mm or more. When the adhesive strength is less than 1.5 N / 10 mm, the flame retardant tape 1 is likely to be displaced from the adherend or easily peeled off.

<Flame Retardant Layer>
The flame retardant layer 4 is a functional layer that imparts flame retardancy to the flame retardant tape 1 together with the flame retardant adhesive layer 3. That is, in the conventional form in which the flame retardant adhesive layer 3 contains a flame retardant, many flame retardants are required to impart flame retardancy, and in that case, there is a problem in that the adhesiveness is liable to decrease. It was. In the present embodiment, in addition to the flame retardant adhesive layer 3, the flame retardant layer 4 is provided to reduce the amount of the flame retardant contained in the flame retardant adhesive layer 3, thereby suppressing a decrease in adhesiveness. .

  The flame retardant layer 4 is mainly composed of a phosphorus-modified resin. 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 ester resin. This is obtained by modifying the side chain of a methacrylic ester resin with a phosphate group. The phosphorus-modified resin is, for example, a phosphorus skeleton polyester resin.

  The flame retardant layer 4 contains 5.0 parts by mass or more and 10.0 parts by mass or less as phosphorus atoms 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 phosphorus atoms. If the amount is less than 5.0 parts by mass as phosphorus atoms, the flame retardancy of the flame retardant tape 1 tends to decrease. Further, it is difficult to include more than 10.0 parts by mass as phosphorus atoms in the phosphorus-modified resin.

  In the case of a phosphorus-modified resin, as in the case of a flame retardant of a phosphorus compound, flame retardancy can be improved by forming a non-flammable film by heating and blocking the inflow of oxygen. Moreover, when the flame retardant tape 1 is melted by heating, the production of solid residue is increased, and the flame retardant property can be improved by reducing the amount of flammable gas produced.

  As a specially modified methacrylic ester resin satisfying such conditions, for example, Kogham HW-500 (trade name) manufactured by Showa Denko KK can be used. Moreover, as a phosphorus frame | skeleton polyester resin which satisfy | fills such conditions, the plus coat | court Z-900 (brand name) by a mutual chemical industry company can be used, for example.

  The flame retardant layer 4 preferably has a thickness of 0.50 times or more that of the substrate 2. If the thickness of the flame retardant layer 4 is less than 0.5 times that of the substrate 2, the flame retardancy tends to be reduced. Further, 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 substrate 2.

  It should be noted that the flame retardant layer 4 has a thickening agent for improving the coating property when applying a solution for a flame retardant layer, which will be described later, and a defoaming agent for suppressing foaming and suppressing rough appearance. An agent may further be 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 the material 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. Of these, polyester polyurethane resin is preferable from the viewpoint of adhesion.

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

Next, a flame retardant layer solution for applying the flame retardant layer 4 is prepared (step 102).
And the flame retardant layer 4 which has a phosphorus modified resin as a main component is formed on the base material 2 using the solution for flame retardant layers (step 103: flame retardant layer formation process). That is, the flame retardant layer 4 is formed by applying the flame retardant layer solution 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 5 is formed on the side opposite to the surface on which the flame retardant layer 4 of the base material 2 is formed using the anchor coat layer solution (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).
And the flame retardant adhesive layer 3 containing a flame retardant is formed on the anchor coat layer 5 using the flame retardant adhesive layer solution (step 107: flame retardant adhesive layer forming step). That is, the flame retardant adhesive layer 3 is formed by applying a solution for the flame retardant adhesive layer 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 pressure-sensitive adhesive layer 3 to impart flame retardancy, but also a flame retardant layer 4 is provided to impart flame retardancy thereto. By containing a predetermined amount of resin, flame retardancy is improved. As a result, the amount of the flame retardant added to the flame retardant adhesive layer 3 can be reduced, and the flame retardant tape 1 can be provided in which the adhesiveness is hardly lowered while maintaining the flame retardancy. Moreover, since the flame-retardant tape 1 of the present embodiment does not contain halogen, for example, even if combustion occurs, generation of harmful gas can be suppressed.

  Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples without departing from the gist thereof.

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

And 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 Kogham HW-500 (trade name) manufactured by Showa Denko KK was dissolved in the solvent as a phosphorus-modified resin. Furthermore, Jurimer AC-10SH (trade name) manufactured by Toagosei Co., Ltd. was used as a thickener, and 2.8 parts by mass was added to 100 parts by mass of Cogham HW-500 to prepare a flame retardant layer solution. . And the flame retardant layer solution was apply | coated to the one side of the base material 2, and the flame retardant layer 4 was formed by making it dry.
At this time, 8.0 parts by mass of phosphorus atoms were included in the flame retardant layer 4 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 substrate 2 and was 13 μm.

Next, the anchor coat layer 5 was formed on the other surface side of the substrate 2 as follows.
First, using toluene as a solvent, a polyester / polyurethane resin was dissolved to prepare an anchor coat layer solution. Here, Seika Bond E-292 (trade name) manufactured by Dainichi Seika Kogyo Co., Ltd. was used as the polyester / polyurethane resin, and Seika Bond C-75N-1.5 (trade name) was used as the curing agent. And the anchor coat layer solution was apply | coated to the other side of the base material 2, and the anchor coat layer 5 was formed by making it dry. Here, the thickness of the anchor coat layer 5 was 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 a solvent, and aluminum hydroxide and melamine polyphosphate were added to the 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 agent were dissolved in this solvent. And the above component was disperse | distributed in the solvent by stirring, and the solution for flame-resistant adhesion layers was created.

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

And the flame retardant adhesive layer 3 was formed by apply | coating the solution for flame retardant adhesive layers to the other surface side of the anchor coat layer 5, and making it dry.
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. And the thickness of the flame-retardant adhesion layer 3 became 30 micrometers.

  The flame retardant tape 1 of this example was prepared by the above process.

(Examples 2 to 8)
A flame retardant tape 1 was prepared in the same manner as in Example 1 except that Example 1 was changed as shown in Table 1. The flame retardant tape 1 of Example 8 is of the type shown in FIG. 1A without the anchor coat layer 5.

(Comparative Examples 1-4)
A flame retardant tape was prepared in the same manner as in Example 1 except that Example 1 was changed as shown in Table 1. Of these, in Comparative Example 1, the amount of phosphorus atoms contained in the flame retardant layer 4 is 4.0 parts by mass below the lower limit of 5.0 parts by mass. In Comparative Example 2, the thickness of the flame retardant layer 4 is 0.34 times lower than the lower limit of 0.50 times that of the substrate 2. Further, in Comparative Example 3, the amount of the flame retardant in the flame retardant adhesive layer 3 is 15.4 parts by mass below the lower limit of 16.0 parts by mass. In Comparative Example 4, the amount of the flame retardant in the flame retardant adhesive layer 3 is 49.6 parts by mass exceeding the upper limit 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 the UL510 standard.
Moreover, the adhesive force was evaluated. The adhesive force measured the adhesive force (N / 10mm) with respect to an alumite board based on the method described in JISZ0237. The measurement temperature was 23 ° C.

〔Evaluation results〕
The evaluation results are shown in Table 1.
About the flame retardant tape 1 of Examples 1-8, all passed the flammability test. Further, the adhesive force was 1.5 N / 10 mm or more, which was good.
On the other hand, all of the flame retardant tapes 1 of Comparative Examples 1 to 3 failed the flammability test.
In the flame retardant tape 1 of Comparative Example 1, the amount of phosphorus atoms in the phosphorus-modified resin contained in the flame retardant layer 4 is as small as 4.0 parts by mass, so the flame retardancy is lowered, and as a result, the flammability test fails It became.
In the flame retardant tape 1 of Comparative Example 2, the flame retardant layer 4 has a thickness of 0.34 with respect to the base material 2, and the flame retardant layer 4 is thin, so that the flame retardant properties are reduced. The sex test failed.
Since the amount of the flame retardant in the flame retardant adhesive layer 3 was as small as 15.4% by mass, the flame retardant tape 1 of Comparative Example 3 was reduced in flame retardancy, and as a result, the flammability test was rejected.
Moreover, about the flame-retardant tape 1 of the comparative example 4, although the combustibility test passed, the adhesive force was insufficient. In other words, the adhesive force was insufficient due to too much flame retardant.
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 addition amount of the flame retardant in the flame retardant adhesive layer 3 are within the above-described ranges. It was confirmed that it was necessary.

DESCRIPTION OF SYMBOLS 1 ... Flame retardant tape, 2 ... Base material, 3 ... Flame retardant adhesion 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;
Provided on one surface side of the base material, a flame retardant adhesive layer containing a flame retardant, and
A flame retardant layer provided on the other surface side of the base material, the main component of which is a phosphorus-modified resin;
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 phosphorus atoms when the phosphorus-modified resin is 100 parts by mass, and the thickness is 0.50 or more times that of the base material. Flame retardant tape.   The flame retardant tape according to claim 1, wherein the flame retardant includes a phosphorus compound.   The flame retardant tape according to claim 1, wherein the flame retardant includes 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 obtained by modifying a side chain of a methacrylic ester resin with a phosphate group.   The flame retardant tape according to any one of claims 1 to 5, wherein the flame retardant adhesive layer has a thickness of 20 µm or more.   The flame retardant tape according to claim 1, further comprising an anchor coat layer between the base material and the flame retardant adhesive layer. A substrate preparation step of preparing a substrate having a thickness of 12 μm or more and 100 μm or less;
A flame retardant adhesive layer forming step of forming a flame retardant adhesive layer containing a flame retardant on one surface side of the substrate;
A flame retardant layer forming step of forming a flame retardant layer mainly composed of a phosphorus-modified resin on the other surface side of the substrate;
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 phosphorus atoms when the phosphorus-modified resin is 100 parts by mass, and the thickness is 0.50 times or more of the base material. A method for producing a flame retardant tape that forms the flame retardant layer.   9. The method according to claim 8, further comprising an 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. Of flame retardant tape.

Images