JPH03259978A - Self-adhesive tape - Google Patents

Abstract

PURPOSE:To prepare a self-adhesive tape which has a substrate prevented from swelling by a solvent, such as a wax remover, and prevents the solvent from penetrating into between the self-adhesive tape and an adherend by forming a coating film layer from a specific coating compsn. on the side edge. CONSTITUTION:A self-adhesive tape is prepd. by forming a coating film layer on the side edge of the tape from a coating compsn. which is obtd. by compounding 100 pts.wt. polyurethane, 2-100 pts.wt. fluororesin (e.g. a tetrafluoroethylene resin), 5-200 pts.wt. silicone oil (e.g. dimethylsilicone oil), a polyether silicone in a molar ratio of its OH group to the NCO group of the polyurethane of (0.7:1) to (1.3:1), and 0.002-20 pts.wt. halogenating agent (e.g. trichloroisocyanuric acid). The polyurethane is obtd. by reacting a polyol (e.g. a polyoxypropylene glycol), triethanolamine, and a polyisocyanate (e.g. 4.4'-diphenylmethane diisocyanate) in a molar ratio of the polyol to triethanolamine of (1:0.05) to (1:2.0) and in a molar ratio of the OH group to the NCO group of (1:1.5) to (1:7).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive tape for attaching a side molding to the side surface of an automobile body, for example.

[Conventional technology]

Conventionally, side moldings attached to the side surfaces of automobile bodies, for example, have been fixed to the body with double-sided adhesive tape. On the other hand, wax is applied to the body to protect the paint. To remove this wax when installing side moldings, the car is washed with wax remover. Furthermore, when refueling with fuel such as Ganlin, the fuel may break down and get on the side edges of the adhesive tape.

[Problem to be solved by the invention]

As mentioned above, if fuel such as wax remover or gasoline comes into contact with the side edges of the adhesive tape, it may swell the resin or rubber that is the base material of the adhesive tape, or cause the adhesive between the body and the adhesive tape or between the side molding and the adhesive tape to swell. There is a problem in that wax remover or fuel penetrates between the adhesive tape and the adhesive tape, reducing the adhesion area of the adhesive tape, resulting in a decrease in adhesive strength such as tensile shear strength and peel strength. For example, when immersed in gasoline or wax remover for 1 hour at room temperature (23 °C), the adhesive area decreases from 100% to 25% and the tensile shear strength from 8.8 kg/crl to 1.5
kg/crl.

The purpose of the present invention is to solve the above-mentioned problems and provide an adhesive tape that does not cause the base material of the adhesive tape to swell, can secure a sufficient adhesive area of the adhesive tape, and has excellent adhesive strength such as tensile shear strength. There is a particular thing.

[Means to solve the problem]

In order to achieve the above object, the present invention uses polyol,
Composed of triethanolamine and polyisocyanate, the molar ratio of polyol:triethanolamine is 1:0
．． 05 to 2.0 and the molar ratio of hydroxyl group (-OH) to isocyanate group (-NCO) is 1:1.5 to 7.
100 parts by weight, 5 to 200 parts by weight of silicone oil,
Polyether silicone has its hydroxyl group (-0H
): Isocyanate group (-NCo) in the polyurethane
) and the halogenating agent in an amount such that the molar ratio is 0.7 to 1.3:l. A method is adopted in which a coating layer formed from a coating composition containing 2 to 20 parts by weight of OD is formed on the side edges.

[Detailed explanation of means]

First, polyethylene (PE) is used as the base material for adhesive tape.
), polypropylene (PP), polyvinyl chloride (PVC)
), synthetic resins such as polyester, foams of the same synthetic resins, rubber, kraft paper, cloth, cellophane, etc. are used.

Next, a coating composition to be applied to the side edges of the adhesive tape to form a coating layer will be described. First, polyurethane will be explained.

Polyols include polyoxypropylene glycol (PPG), propylene oxide adduct of glycerin, propylene oxide adduct of trimethylolpropane, pentaerythritol nofuropylene oxide adduct, triethylene glycol (TG), and propylene oxide adduct of sucrose. Examples include compounds such as The polyoxypropylene glycol preferably has a number average molecular weight in the range of 8.0 to 6,000.

The amine is triethanolamine, and a crosslinking reaction occurs with monoethanolamine and jetanolamine.
It is unsuitable because polyurethane gels.

Polyisocyanate is a compound having a plurality of isocyanate groups, such as 2,4-1-lylene diisocyanate (TDI), 65/35 (ratio of 2,4-tolylene diisocyanate and 2,6-t-lylene diisocyanate, Same below) Tolylene diisocyanate, 80/
20 Tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), dianisidine diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, metaxylene diisocyanate, 1,5-naphthalene diisocyanate (NDI), hydrogenated 4,4'-diphenylmethane Diisocyanate, hydrogenated xylene diisocyanate, hydrogenated 2,4-tolylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 8o/20 tolylene diisocyanate, isophorone diisocyanate (IPDI), 4.4', 4'
-triphenylmethane triisocyanate, tris(p
-isocyanate phenyl) thiophosphate, etc. are used.

The molar ratio of the polyol:triethanolamine is 1:
It is 0.05 to 2.0. When this ratio is less than 0.05 or more than 2.0, the adhesion of the resulting coating film to the side edges of the adhesive tape is greatly reduced.

Further, the molar ratio of hydroxyl groups (-OH) in the polyol to isocyanate groups (-NCO) in the polyisocyanate is 1:1.5 to 7, and the isocyanate groups are blended in excess to the hydroxyl groups.

When this ratio is less than 1.5 or more than 7, the adhesion of the resulting coating film to the side edges of the adhesive tape decreases, and may not adhere properly.

Fluororesins include tetrafluoroethylene resin,
Tetrafluoroethylene-hexafluoropropylene copolymer resin, trifluorochloroethylene resin, vinylidene fluoride resin, etc. are used. The blending ratio of this fluororesin is in the range of 2 to 100 parts by weight per 100 parts by weight of the polyurethane. If the proportion is less than 2 parts by weight, performance such as solvent resistance will not improve, and if it exceeds 100 parts by weight, it will be difficult to apply the coating composition.

As the silicone oil, dimethyl silicone oil, methyl chloride silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, fluorosilicone oil, etc. are used. The blending ratio of this silicone oil is 5 parts by weight based on 100 parts by weight of the polyurethane.
~200 parts by weight. If the proportion is less than 5 parts by weight, it is impossible to improve water repellency, and even if it exceeds 200 parts by weight, the effect of improving water repellency remains the same, but the adhesion deteriorates. .

The polyether silicone is a polymer having a hydroxyl group and a siloxane bond, and for example, one having the following structural formula can be used.

This polyether silicone is made by reacting a copolymer of ethylene oxide and propylene oxide with silicone, but it may also be made by reacting a homopolymer of ethylene oxide or propylene oxide with silicone. The polyether silicone preferably has a hydroxyl value of about 45 to 60, and this polyether silicone functions as a curing agent for the polyurethane and also contributes to improving water repellency. The molar ratio of hydroxyl groups in the polyether silicone to isocyanate groups in the polyurethane is in the range of 0.7 to 1.3:1. This molar ratio is 0
．． If it is less than 7, the adhesion of the resulting coating film to the side edges of the adhesive tape will decrease, and it will not be possible to improve water repellency or the like.

Moreover, when it exceeds 1.3, the adhesion of the coating film to the side edge of the adhesive tape decreases.

As a halogenating agent, N-promsuccinimide (N
BSI), acid imide halogen compounds such as N-bromphthalimide, trichloroisocyanuric acid (TCIA)
, isocyanuric acid halides such as dichloroisocyanuric acid, halogenated hydantoins such as dichlorodimethylhydantoin, alkyl hypohalides, and the like.

The above-mentioned alkyl hypohalides are normal, secondary or tertiary alkyl hypohalides, particularly stable tertiary alkyl chlorides and bromides, such as tertiary butyl hypobromide, tertiary amyl hypobromide, etc. is preferred, and halogen-substituted alkyl hypochlorides such as dichloro, trichloro or fluoromethyl hypochloride can also be used.

The halogenating agent was added in an amount of 0.0% per 100 parts by weight of the polyurethane. 2 to 20 parts by weight of OO is blended.

If the blending ratio is less than 0.002 parts by weight, the degree of halogenation is small, so there is little improvement in adhesion, and if it exceeds 20 parts by weight, the stability of the coating composition deteriorates.

In the present invention, a solvent may be added if necessary. Examples of this solvent include n-hexane, cyclohexane, benzene, toluene, xylene, ethylbenzene,
Trichlorethylene, methylene chloride, 1,1.1
- trichloroethane, ethylene chloride, dimethylformamide, dimethyl sulfoxide, methyl ethyl ketone,
Examples include atocene, methyl isopropyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, anisole, and tetrahydrofuran.

The blending ratio of this solvent is 10 parts by weight in 100 parts by weight of the coating composition.
A range of 90 parts by weight is preferred. If the blending ratio is less than 10 parts by weight, the solid content will be relatively high and the viscosity of the coating composition will increase, making it difficult to apply and will likely lead to a decrease in adhesion; if it exceeds 90 parts by weight, On the contrary, the proportion of solids becomes low and the film thickness of the coating composition becomes thin, which is not preferable as a coating material.

The coating composition used in the present invention is prepared, for example, as follows. First, the polyol, triethanolamine, polyisocyanate, and a necessary solvent are appropriately selected and mixed, and the mixture is reacted at 80° C. for 3 hours in dry nitrogen gas to prepare a polyurethane having isocyanate groups.

Next, with respect to 100 parts by weight of this polyurethane, 2 to 100 parts by weight of fluororesin, 5 to 200 parts by weight of silicone oil, and polyether silicone are added in an amount such that hydroxyl group: isocyanate group = 0.7 to 1.3:1 and halogen. A coating composition is obtained by adding 0.002 to 20 parts by weight of a curing agent and further adding a solvent to adjust the viscosity to a level suitable for coating.

In this case, a part of the fluororesin may be replaced with molybdenum disulfide, glass fiber, carbon fiber, polyethylene, silicon oxide, calcium carbonate, magnesium carbonate, clay, or the like.

[Effect]

By adopting the above method, the silicone oil, polyether silicone, and fluororesin in the coating composition constituting the coating layer formed on the side edge of the adhesive tape exhibit properties such as water repellency and solvent resistance. , the permeation of the solvent from the side edge of the adhesive tape into the interior is suppressed, and the halogenating agent halogenates the side edge of the adhesive tape to improve the intermolecular force between the side edge and the coating layer, and polyol in a predetermined proportion;
It is presumed that the adhesion of the coating layer to the side edge of the adhesive tape is improved by the effects of hydrogen bonding and the like caused by the isocyanate group-containing polyurethane, which is composed of triethanolamine and polyisocyanate and contains an excess of isocyanate groups.

[Examples 1 to IO and Comparative Examples 1 and 2] Examples embodying the present invention will be described below with reference to FIG. 1 and in comparison with comparative examples.

In addition, on each side, parts represent parts by weight.

As shown in FIG. 1, an adhesive layer 3 is formed on one side of a base material 2 of an adhesive tape l formed in a sheet shape, and an adhesive layer 4 is formed on the other side. Moreover, a coating film layer 5 made of a coating composition is formed on both side edges of the adhesive tape 1. In addition, in FIG. 1, this adhesive tape 1
The release paper has been peeled off.

(1) Preparation of adhesive 98 parts of butyl acrylate, 2 parts of acrylic acid, 0.2 parts of benzoyl peroxide, 90 parts of toluene, and 90 parts of ethyl acetate were mixed and reacted at 80° C. for 10 hours. Then, 2 parts of isophorone diisocyanate was added to 100 parts of this reaction solution to prepare an adhesive.

(2) Preparation of adhesive Polybutylene adipate (weight average molecular weight approximately 2000)
200 parts of 4,4-diphenylmethane diisocyanate, 300 parts of trichloroethylene, and 300 parts of dimethylformamide were mixed, and after reacting in dry nitrogen at 80°C for 3 hours, 12.2 parts of ethylene glycol was added. The adhesive was prepared by reacting for 20 minutes in dry nitrogen at 80°C.

(3) Preparation of adhesive tape 1 The base material 2 is foamed polyethylene with a thickness of 1 mm that has been expanded 8 times, and the adhesive is applied to one side of the base material 2 and the adhesive is applied to the other side. Adhesive tape 1 was produced.

(,4) Preparation of coating composition First, polyurethane was synthesized as follows. Polyol (PO), triethanolamine (TEA), and polyisocyanate (PI) shown in Table 1 below were mixed in trichlorethylene, and the mixture was heated in a nitrogen gas atmosphere.
Polyurethane was synthesized by reacting at 0°C for 3 hours. The obtained polyurethane had a solid content of 83% and trichlorethylene 1
7% Table-1 Abbreviations in Table-1 represent the following meanings.

PPG 3000: Polyoxypropylene glycol with a number average molecular weight of 3000 PPG 1000: Polyoxypropylene glycol with a number average molecular weight of 1000 PPG 2000: Polyoxypropylene glycol with a number average molecular weight of 2000 TG 3000: Triethylene glycol with a number average molecular weight of 3000 Table 2 The abbreviations in Table-2 represent the following meanings.

Cole TG 1000: Triethylene glycol with a number average molecular weight of 1000 TG 2000: Triethylene glycol with a number average molecular weight of 2000 MDI: 4,4'-diphenylmethane diisocyanate NDI: 1,5-naphthalene diisocyanate XDI:
Xylylene diisocyanate IPDI: Isophorone diisocyanate Next, predetermined amounts of fluororesin, silicone oil, polyether silicone (PESi) and halogenating agent shown in Table 2 below were blended with 100 parts of the solid content of the above various polyurethanes. In the coating composition, fluororesin refers to tetrafluoroethylene resin.

DMS i represents dimethyl silicone oil.

(1): Viscosity of 10,000 centistokes (C3t) (
2): Viscosity of 60,000 C3t (3): Viscosity of 100,000 cSt The polyether silicone has the following hydroxyl value.

(a) 56, (b) 48, (C) 47, (d) 5
9, (e) 46, (f) 52, (g) 51, (h
) 50 , (i) 49 The halogenating agent represents the following.

TCIA:) Lichloroisocyanuric acid NBSI: N-promsuccinimide t-BHC:
Tertiary Butyl Hypochloride Also, as a comparative example, an adhesive tape without coating was prepared.

(5) Preparation of test piece The composition of each of the above Examples or Comparative Examples was applied to the side edge of the adhesive tape 1, and then left at room temperature for -1 week to be subjected to a test.

Then, the side coated with the adhesive of the adhesive tape 1 was adhered to a painted steel plate, and the side coated with the adhesive was adhered to a vinyl chloride resin plate to prepare a test piece.

(6) Measurement of adhesive area and tensile shear strength Each test piece was heated at room temperature of 23°C using gasoline (G) as a solvent,
After each sample was immersed in wax remover (W) for 1 hour, the adhesive area and tensile shear strength were measured at a tensile rate of 50 mm/min. The results are shown in Table-3.

Table 3 Examples 1 to 10 of the present invention as shown in Cloth 3 above
, the adhesive area for any solvent is 97~
As high as 99%, the tensile shear strength is 8.5 to 8.7.
It shows a high value of kg/crl.

This means that the solvent may be present between the adhesive tape and the painted steel plate,
It can be seen that the adhesive tape did not penetrate into the gap between the adhesive tape and the vinyl chloride resin plate, and the adhesive state was maintained.

This is because the coating layer 5 formed by applying the coating composition of each example to the side edge of the adhesive tape 1 is made of silicone oil,
Water repellent due to polyether silicone and fluororesin,
In addition to exhibiting performance such as solvent resistance, the halogenating agent halogenates the base material 2 to improve mutual intermolecular force, and is made of a predetermined amount of polyol, triethanolamine, and polyisocyanate, and has isocyanate groups. This is believed to be due to excellent adhesion to the side edges of the adhesive tape 1 due to hydrogen bonding caused by polyurethane.

On the other hand, in Comparative Examples 1 and 2 in which the coating layer 5 was not formed on the side edges of the adhesive tape, the adhesive area was reduced to 31 to 35%, and the tensile shear strength was also as low as 1.5 kg/cnf.

Therefore, if a side molding is attached to the side of an automobile body using an adhesive tape with the coating composition of each example applied to the side edge, even if gasoline or wax remover adheres to the side edge of the adhesive tape, The side molding is held to the body with sufficient bonding strength.

Note that the present invention is not limited to the above embodiments,
For example, it is also used as an adhesive tape for use in chemical equipment where solvents such as toluene and xylene may adhere, and members where kerosene may adhere.

〔Effect of the invention〕

The adhesive tape of the present invention can prevent the base material of the adhesive tape from swelling due to solvents such as wax remover and fuel, and can also prevent the solvent from penetrating between the adhesive tape and the adherend. This has the effect that the adhesive strength between the adhesive and the adherend is sufficiently maintained.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view of an adhesive tape showing an embodiment of the present invention. 1... Adhesive tape, 5... Paint film layer

Claims (1)

[Claims] 1. Consisting of polyol, triethanolamine and polyisocyanate, the molar ratio of polyol:triethanolamine is 1:0.05-2.0, and the hydroxyl group (
-OH): molar ratio of isocyanate group (-NCO) is 1
:1.5-7 for 100 parts by weight of polyurethane,
2 to 100 parts by weight of fluororesin, 5 parts of silicone oil
~200 parts by weight, polyether silicone in an amount such that the molar ratio of its hydroxyl group (-OH) to isocyanate group (-NCO) in the polyurethane is 0.7 to 1.3:1, and 0.00 parts by weight of the halogenating agent. An adhesive tape having a coating layer (5) formed from a coating composition containing 0.02 to 20 parts by weight on the side edge.