JPS6363776A - Molding - Google Patents

Abstract

PURPOSE:To provide a molding which causes neither peeling off from adherends even when a polyolefin tape is used, nor lowering in tack under high-temperature conditions, by providing a specified pressure-sensitive adhesive layer on the back of a molding base. CONSTITUTION:100pts.wt. poly(meth)acrylic acid derivative having active hydrogen atoms (e.g., 2-hydroxyethyl acrylate) is blended with 0.01-50pts.wt. silicone oil having at least one functional group selected from the group consisting of hydroxyl, mercapto, carboxyl, amino carbamoyl and oxy groups on side chains and 0.1-80pts.wt. polyisocyanate (e.g., tolylene diisocyanate) to obtain a tacky adhesive. A layer 8 composed of the adhesive is formed on one side of a base tape 4, on the other side of which an adhesive layer 6 is formed through a primer layer 5. The tacky layer 8 is covered with a release paper 9 to obtain a tacky adhesive tape 3. The tape 3 is stuck on the back of a molding base 2 through a primer layer 7.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a molding for an automobile, and more particularly to a molding structure in which a tape is adhered to the back surface of a molding base material.

(Prior Art) Conventionally, the molding has been mainly composed of a plate-shaped molding base material and a double-sided tape adhered to the back surface of the molding base material.

The molding base material in this molding is usually made of polyvinyl chloride or the like, and has a decorative function and a protective function for adherends such as automobile bodies and bumpers.

(Problems to be solved by the invention) However, the molding base material made of polyvinyl chloride expands and contracts in environments with large temperature differences, causing dimensional changes, and low-molecular compounds in the molding base material volatilize. In addition, the plasticizer and stabilizer decompose due to interaction with heat, light, moisture, etc. and become low molecular weight, which eventually evaporates, causing the size of the mold base material to change as described above.

When the molding base material undergoes a dimensional change, there is a problem in that the molding peels off from the adherend if the adhesive used between the double-sided tape and the covering body has low adhesive strength.

Furthermore, when the base tape of the double-sided tape is made of a polyolefin foam or the like, there is a problem that the adhesive force to the adherend is insufficient because the polyolefin does not have an active functional group.

Therefore, various adhesives with high adhesive strength have been proposed, such as adhesives whose main components are polyalkyl acrylate, polyalkyl methacrylate, etc., but even these adhesives still lack adhesive strength. In particular, there was a problem that the adhesive force inevitably decreased under high temperature atmosphere.

The object of the present invention is to use polyvinyl chloride as the mold base material,
Another object of the present invention is to provide a molding which does not peel off from an adherend even when polyolefin is used as the tape, and which suppresses a decrease in adhesive strength even when placed in a high R atmosphere.

Structure of the Invention (Means for Solving Problems) The present invention provides a molding comprising a molding base material and an adhesive layer formed on the back side of the molding base material. Acrylic acid derivative and/or polyacrylic acid derivative and side chain (hydroxyl group, mercapto group, carboxyl group, amine group, carbamoyl group,
The above-mentioned problems are attempted to be solved by forming the adhesive from a silicone oil having at least one functional group selected from oxy groups and polyisocyanate.

(Function) The silicone oil having a side chain such as a hydroxyl group and the polyacrylic acid derivative and/or polymethacrylic acid derivative having active hydrogen are three-dimensionally bonded by the polyisocyanate, and the silicone oil causes the adhesive molecules to flow. I will be kept alive. Therefore, the adhesive exhibits excellent viscosity. The heat resistance of the adhesive is enhanced by the sr-o-bonds of the silicone oil. Therefore, the tape becomes difficult to peel off from the adherend even at high temperatures.

(Example) Next, an example embodying the present invention will be described based on the drawings.

[Structure of Molding] As shown in the drawings, the molding 1 of this embodiment includes a thick plate-shaped molding base material 2, and an adhesive tape 3 attached to the back side of the molding base material 2 via a primer layer 7. It consists of

The adhesive tape 3 has a base tape 4, an adhesive period 6 formed on one side of the base tape 4 via a primer layer 5, and an adhesive layer 8 formed on the other side. The surface of the adhesive layer 8 is covered with a release paper 9. The molding 1 is joined to the adherend by peeling off the release paper 9 and pressing the molding against the adherend such as an automobile door.

The molding base material 2 is formed from polyolefin such as polyvinyl chloride or EPDM. The base tape 4 can be obtained from a sheet-like material made by foaming polyethylene five times, but it can also be made from non-woven fabric such as polyethylene, film, synthetic paper, etc.

As the primer layer 5.7, various primers used for polyolefins are used, such as a rubber-based primer obtained by graft polymerizing a methacrylic acid derivative onto chloroprene rubber.

[Constitution of Adhesive] The adhesive contains silicone oil having a hydroxyl group, mercapto group, carboxyl group, amine group, carbamoyl group, or oxy group in the side chain, and a polyacrylic acid derivative and/or polymethacrylic acid derivative having active hydrogen. It consists of a conductor and polyisocyanate.

This adhesive is obtained by mixing the silicone oil, a polyacrylic acid derivative and/or polymethacrylic acid derivative having an active water system, and the polyisocyanate. It can also be obtained by copolymerizing an active acrylic acid derivative and/or methacrylic acid derivative or an inactive acrylic acid derivative and/or methacrylic acid derivative with another vinyl compound having active hydrogen in the presence of hydrogen.

[Raw Materials for Adhesive] Next, the raw materials used to produce the adhesive will be described. First, a silicone oil having the general formula % is prepared as the silicone oil. However, in the above general formula, X is OH group, C0OH group, R000H group, R
O (RO) nR- group, SH group, R3 day group, N day 2 group,
R\ means 2 groups, RCON means 2 groups, R means an alkylene group, R- means an alkyl group, and m and n each mean a positive integer.

The polyisocyanate includes tolylene diisocyanate (TDI), methylene bis(4-phenylisocyanate 1-) (MDI), 1.5-naphthalene diisocyanate, xylylene diisocyanate (XDI>, 4.4
．． 4-Triphenylmethane triisocyanate (T
T I>, aromatic polyisocyanates such as isophorone diisocyanate, 4.4-methylenebis(cyclohexyl isocyanate>(H-MDI>), alicyclic polyisocyanates such as hexahydroxylylene diisocyanate, 1.6-hexamethylene diisocyanate, etc. aliphatic polyisocyanate, 1 to 3 mol adduct of tolylene diisocyanate of trimethylolpropane (TMP-3
TD I>, 1-3 mol adduct of trimethylolpropane with isophorone diisocyanate (TMP-I PDI
”), 2 of 4,4-diphenylmethane diisocyanate or tolylene diisocyanate for a bare alkylene oxide glycol such as polypropylene glycol.
Compounds with terminal NGO groups such as molar adducts are used.

Polyacrylic acid derivatives having active hydrogen, polymethacrylic 11 conductors, etc., are made of acrylic acid derivatives containing vinyl compounds having carboxyl groups such as acrylic acid and hydroxyl groups such as 2-hydroxylethyl acrylate. Obtained by polymerization method.

These polymerization methods are carried out according to conventional methods using known polymerization initiators such as benzoyl peroxide, di-2-ethylxyl peroxydicarbonate, or di-3-methoxybutyl peroxydicarbonate.

The acrylic acid derivative can be used either with or without active hydrogen, but when one without active hydrogen is used, it is used together with a vinyl compound having active hydrogen. Examples of such acrylic acid derivatives include methyl acrylate (MA) and ethyl acrylate (F
A), Furkyl acrylate such as n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, IS○-butyl acrylate, hydroxyalkyl acrylate such as 2-hydroxyethyl acrylate, aminoethyl acrylate, dimethylaminoethyl acrylate, etc. An example is aminoalkyl acrylate.

In addition, examples of vinyl compounds having active hydrogen include acrylic acid, methacrylic acid, maleic acid, fumaric acid, fumaric acid,
Citraconic acid, itaconic acid, the above-mentioned hydroxyalkyl acrylate, etc. are necessary, but when the latter acrylic acid derivative is used, it is not necessarily necessary to copolymerize acrylic acid, etc.

Next, the polyacrylic acid derivative is methyl methacrylate (
MMA), ethyl methacrylate, n-propyl methacrylate (PMA), n-butyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, 15O-butyl methacrylate, etc., alkyl methacrylate-1 to 2-hydroxyethyl methacrylate-1 There are methacrylic acid derivatives such as hydroxyalkyl methacrylates such as ~, aminoethyl methacrylate-1~, and aminoalkyl methacrylates such as dimethylaminoethyl methacrylate. The vinyl compound having active hydrogen is the same as above.

[Preparation of Adhesive] In this example, the above three types of raw materials are mixed in the presence of a solvent, and the mixture is applied to the base tape and cured. Since the polyisocyanate reacts, the three types of raw materials are mixed just before applying the adhesive.

Solvents used in this mixing include aliphatic hydrocarbons such as n-hexane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene, acetone, methyl ethyl ketone,
Ketones such as methyl butyl ketone, ethers such as tetrahydrofuran, esters such as methyl acetate, propyl acetate, butyl acetate, halogenated hydrocarbons such as methylene chloride, 1.1.1-trichloroethane, trichloroethylene, dimethyl sulfoxide ( A single solvent or a mixed solvent such as DMSO>, dimethylformamide, etc. is used.The amount of the solvent used is 5 to 60 parts by weight based on 100 parts by weight of the total amount of the three types of raw materials.

In addition, in the above mixing, the silicone oil and the polyacrylic acid derivative and/or the polyacrylic acid derivative having active hydrogen are first mixed to prepare a mixture, and then the mixture is reacted with the polyisocyanate. A method is adopted in which

In this case, the silicone oil is 0.01 to 50 parts by weight and the polyisocyanate is 0.1 to 80 parts by weight based on 100 parts by weight of the polyacrylic acid derivative and/or polymethacrylic acid derivative having active hydrogen. mixed.

[Experimental Example] Next, the effects of this example will be explained based on a specific experimental example.

First, a molding base material 2 was obtained by injection molding the polyvinyl chloride composition shown in Table 1 at 200°C.

Table 1 Next, silicone oils according to the general formula described in Table 2 were prepared.

Table 2 Next, a polyacrylic IH conductor was produced from the components shown in Table 3 using benzoyl peroxide as a polymerization catalyst.

Table 3 Adhesives were prepared by mixing various silicone oils and polyisocyanates in various weight proportions with 100 parts by weight of the polyacrylic acid derivative, and the adhesives were used to form polyvinyl chloride mold base materials. A molding made of a polyethylene base tape and an automobile body were joined. Then, the shear force (Q/crit) and peel force (C1/25.4 mm) at 80'C were measured. The results are shown in Table 4.

In Table 4, sample symbols ■ to ■ indicate the silicone oils listed in Table 2, and the symbol for polyisocyanate means the above-mentioned symbol.

Table 4 Note 1) * indicates that the adhesive strength of the adhesive was too high and the base tape was destroyed.

Note 2) The molecular weight of PPG-TDM is approximately 1350.

As described above, the adhesive of the present invention exhibits excellent adhesiveness.

Note that the present invention is not limited to the above-mentioned embodiments, and can also be implemented in the following embodiments, for example.

(1) As the adhesive for the adhesive layer 6, any adhesive can be used as long as it exhibits the same adhesive force as the adhesive according to the present invention.

(2) Various primers can be used in the primer layer 5.7 as long as they do not impair the effects of the present invention, and in some cases, they may not be used.

Effects of the Invention As detailed above, the present invention can firmly bond the molding to the adherend even if polyvinyl chloride is used as the molding base material or polyolefin is used as the base tape. It has a immersive effect. However, the effect is maintained even in a high temperature atmosphere.

[Brief explanation of the drawing]

The drawing is a cross-sectional view of the embodiment. DESCRIPTION OF SYMBOLS 1...Mall, 2...Mall base material, 3...Tape, 8...Adhesive layer

Claims (1)

[Claims] 1. In a molding (1) consisting of a molding base material (2) and an adhesive layer (8) formed on the back side of the molding base material (2), the adhesive layer (8) ) has an active hydrogen, a polyacrylic acid derivative and/or a polymethacrylic acid derivative, and a hydroxyl group, mercapto group, carboxyl group in the side chain,
silicone oil having at least one functional group selected from an amino group, a carbamoyl group, and an oxy group;
A molding characterized in that it is formed of an adhesive made of polyisocyanate. 2. The adhesive contains 0.01 to 50 parts by weight of silicone oil and 0.1 to 80 parts by weight of polyisocyanate based on 100 parts by weight of the polyacrylic acid derivative and/or polymethacrylic acid derivative having active hydrogen. The molding according to claim 1, which contains the molding material in a proportion.