JPS602064B2 - Method for producing sustained release fragrance composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a sustained-release fragrance composition, and more particularly, to a method for producing a sustained-release monochromatic fragrance composition in which a fragrance is impregnated and absorbed into an ethylene monomonovinyl acid copolymer resin. .

An object of the present invention is to provide a method for producing a sustained release I fragrance composition that has excellent fragrance resistance, perfectly retains its shape, and can be effectively impregnated with a fragrance.

Sustained-release fragrance compositions that currently dominate the fragrance market include so-called gel fragrances in which fragrance is dispersed in hydrogels such as agar and carrageenan using surfactants.

This gel air freshener is relatively popular due to its excellent volatilization mechanism, which releases fragrance slowly through the slow evaporation of water, and its ability to easily be colored into beautiful colors.
1. In order to overcome the disadvantage of water-soluble gels that their shape is easily broken by physical external force, a strong container as a protector is always required. ■The maximum amount of fragrance that can be dispersed is limited to around 10% of the gel weight, so in order to meet the one to two month usage period normally required for air fresheners, a relatively large amount of 70 to 150 yuan per piece is required. It takes. Because it is a lake water-soluble gel, it easily freezes in environments below 0°C, which causes water separation when the ice thaws. [4'] As the gel surface hardens into a film as 4' is dispersed, the effective brightness of the fragrance is relatively small. (On average, it is about 35% of the added fragrance). The inventors have improved the above-mentioned drawbacks.
As a result of our extensive search for a sustained release fragrance composition that eliminates this problem, we have come to the conclusion that a thermoplastic resin impregnated with a large amount of fragrance may be most suitable for this purpose. Of course, there have been aromatized resins in which thermoplastic resins contain a small amount of 1% or less of fragrance, and techniques for adding fragrance to these resins are also known. That is, a fragrance is added in advance to the raw resin before molding, and this is heated from 150 o'clock to 200 o'clock.
This is a method in which the material is melted and kneaded under internal and external heating and then molded using various molding methods. However, in such a method, as a result of volatilization of the low-boiling point part of the fragrance and qualitative thermal deterioration that occurs during the heating process, the aroma of the finished scented molded product will be significantly different from that of the fragrance used. In many cases, to prevent this, it is necessary to limit the fragrances used to high boiling point ingredients that are unlikely to cause radiance or thermal deterioration. It has never been possible to create a sustained-release fragrance composition for use as an aromatic agent, which requires high volatility. The inventors have learned from the knowledge obtained regarding container materials for fragrances or flavored products that ``among thermoplastic resins, resins other than polyethylene and polypropylene, such as polyvinyl chloride, polythretin, polymethyl methacrylate, and polyvinyl acetate, etc. It also has poor fragrance resistance, and when it comes into contact with fragrances, it absorbs them even at room temperature, causing swelling, softening, and
Due to the fact that these thermoplastic resins with poor fragrance resistance can be used as a material that absorbs fragrances and absorb an appropriate amount of fragrances, it is possible to achieve the desired goal. With the idea that a sustained-release fragrance composition that completely reproduces the scent could be obtained, we conducted repeated experiments on various thermoplastic resins, including those mentioned above, with the goal of selecting the optimal material.

As a result, polyvinyl chloride resins generally require a very long time for absorption, while polystyrene resins and polyvinyl acetate resins tend to swell and soften in a short period of time, leading to deformation and collapse.

The technology for producing sustained-release fragrance compositions made from polyvinyl chloride among thermoplastic resins is known from the description in JP-A-52-145530, but the contents of Examples 1 and 2 of the same publication are Since the findings were significantly different from what the inventors had obtained through experiments, a confirmation test was conducted just to be sure, and it was reconfirmed that the inventors' experimental results were correct. For example, in Example 1 described in the same publication, a polyvinyl chloride disc-shaped molded product (weight: 1 kg) containing 33% DOP was soaked in 3 gr of fragrance at 2000°C for 2 hours, and all of the fragrance nutrients were impregnated and absorbed ( 25 per weight of polyvinyl chloride molded product
%), but the inventor, etc. also has a DOP of 33%.
Completely immerse 1 female r containing polyvinyl chloride pellets (cylindrical shape with diameter 3 and width 3) in 30g of fragrance for 200
When we measured the amount of perfume impregnated and absorbed after 2 hours at 0.0, it was only 0.6 despite the large surface area and the pellet.
group (6% of the pellet weight).

By bringing a certain type of ethylene-vinyl acetate resin into contact with a certain type of fragrance under specific conditions, the inventor has developed a method that absorbs a large amount of the fragrance in a short period of time, without causing any major swelling, softening, or change. The present invention was completed based on the discovery that the fragrance exhibits the effect of slowly dispersing over a long period of time without deteriorating in quality. That is, the present invention is characterized in that the pellets of ethylene-vinyl acetate copolymer resin are brought into contact with the perfume under temperature conditions that substantially prevent the pellets from rutting, thereby impregnating and absorbing the perfume into the pellets. pellet-shaped sustained release I
The present invention provides a method for producing a fragrance composition.

The ethylene-vinyl acetate copolymer resin used in the present invention has a vinyl acetate content of 19 to 4% by weight, more preferably 25 to 39% by weight. Moreover, if the temperature exceeds this range, the resin will swell and soften significantly.The fragrance used in the present invention contains hydrocarbons and/or esters as essential components.
Examples of hydrocarbons include monoterbene hydrocarbons such as limonene, Q-pinene, and 8-pinene; sesquiterbene hydrocarbons such as caryophyllene, santarene, and thobcene; diterbene hydrocarbons such as abietin and camphorene; aromatic hydrocarbons such as styrene; Examples of esters include aliphatic or aromatic carboxylic acid esters having 20 or less carbon atoms, more preferably 15 or less carbon atoms, and specific examples include isoamyl acetate, geranyl acetate, and citronellyl. Acetate, linalyl acetate, benzyl acetate, benzyl benzoate, benzyl salicylate, cinnamyl cinnamate, isoamyl undecylenate, cedryl acetate, and the like.

The fragrance is usually provided in the present invention as a mixed fragrance, but in this case, hydrocarbons and/or esters account for 30% of the total fragrance ingredients.
% or more, especially 50% or more.

The perfume may contain a preservative if necessary. It is also preferable to use hydrocarbon-based and ester-based retention agents as the retention agent. If the perfume contains almost no hydrocarbons or esters, a sufficient impregnating effect cannot be expected.

In order to impregnate and absorb the fragrance into the ethylene-vinyl acetate copolymer resin, it is necessary to use the resin in pellet form. Preferably, the pellet is one with a grain size of 1 or less, especially about 2 to 6 grains.The operation of impregnating and absorbing the fragrance is usually carried out by mixing the two at room temperature or with slight heating.The method of the present invention As is clear from the fact that the pellets are essentially impregnated and absorbed, high temperatures that would cause the pellets to fuse together must be avoided.Generally, the operating temperature is 50 ooohs.
If the temperature exceeds this temperature, adverse effects such as deterioration of the fragrance will occur, and if the temperature is too low, the absorption effect will not be sufficient. When mixing the fragrance and the betel fat pellets, it is preferable to use the required amount of the fragrance and mix them together, and usually the fragrance is mixed in an amount equal to or less than the resin, especially in a state of less than 5% by weight. It is desirable to impregnate and absorb substantially all of the fragrance present in the system.

In the case of the ethylene-vinyl acetate copolymer resin molded product that the inventors intend to provide, the impregnation and absorption time of the fragrance will vary depending on the content of vinyl acetate (the time is short when the content is high, and long when the content is low). ), it is possible to impregnate and absorb 40 to 100% of the fragrance based on the weight of the molded material within a short period of 2 to 1 hour by soaking the bond at room temperature, and furthermore, the fragrance does not undergo thermal changes. When soaking is carried out under salted conditions at the critical temperature of 45 o C to 50 o'clock, the impregnation and absorption time is further increased by 1.
It has been found that the time can be shortened to ~5 hours.

The ethylene-vinyl acetate copolymer resin pellets made by the above method that have been impregnated and absorbed have no significant softening, deformation, or molding, although the volume increases in proportion to the amount of impregnation and absorption. There isn't. In addition, since the fragrance-impregnated pellet thus produced has an extremely high fragrance content as mentioned above, only a small amount is required when using it as a luminescence matrix, and it can be stored in a simple and convenient container, such as a non-woven fabric container. It can be used for products such as air fresheners simply by filling or enclosing it in bags, polyethylene film packs with ventilation holes, etc.

Furthermore, since this beret impregnates and absorbs the fragrance in the form of a resin plasticizer, its seedlings are slow-release and long-lasting, and the effective emission rate of the fragrance is extremely high at over 50%. can do.

Furthermore, it is possible to impregnate and absorb the fragrance and at the same time color the pellet in a beautiful tone by simply dissolving an oil-soluble pigment of a desired color in the fragrance to be used.

Examples will be described below, but the vinyl acetate content of the ethylene-vinyl acetate copolymer resin pellets used, the type and shape of the pellets, etc. are not limited to those of these examples.

Example 1 A transparent pellet of 70 gr of ethylene-vinyl acetate copolymer resin manufactured by Mitsui Polychemical Co., Ltd. (trade name: EVAFLEX-150 (vinyl acetate content: 33%)) and oilyell were prepared in advance.
Seal 30g of a lemon-based blended fragrance (containing 32% hydrocarbons such as limonene) colored yellow in an eggplant-shaped flask (2) of a rotary evaporator, and heat at 40 revolutions per minute at room temperature (200C). Rotated.

The pellet absorbs and absorbs the fragrance in about 2G minutes, but as the rotation continues, the wet pellet surface gradually dries up (because it penetrates into the interior), and after an hour it becomes smooth and fluid. The result is a nice translucent yellow pellet impregnated with aromatics. This fragrance-impregnated pellet LOGR was filled into a thin non-woven bag made in advance and placed in a flush toilet for 50 days.The performance as an air freshener was evaluated by a panel sensory test. Strength is 4-2.75
(value based on the six-level odor display method).

Furthermore, when the perfume volatilization rate after the end of the period was measured, it was found to be 58% (weight loss: 1.78 bait/impregnated perfume amount: 3 gr x 100), which was an extremely good result.

Example 2 A transparent pellet of 70 gr of ethylene monovinyl acetate copolymer resin trade name EVAFLEX-460 (vinyl acetate content 19%) manufactured by Mitsui Polychemical Co., Ltd.
30g of a lemon-based blended fragrance (containing 32% of hydrocarbons such as limonene) that had been colored amber yellow was sealed in a flask of a rotary evaporator in the same manner as in Example 1, and the bottom of the flask was immersed in a 45°C water bath. 30 per minute
After 5 hours of rotation, a perfume-impregnated pellet similar to that of Example 1 was completed.

The performance as an aromatic agent was exactly the same as in Example 1.

Example 3 Transparent pellet 70 of EVAFLEX-150 of Example 1
In the evening, mix osmanthus-based fragrances (ethyl acetate, amyl acetate, amyl butyrate, ethyl caproate,
Contains 43% of esters such as benzyl acetate) 30 days in the same manner as in Example 1. The flask was sealed in a J-evaporator and rotated at 30 revolutions per minute while the bottom surface of the flask was immersed in a water bath at 30°C, and a pellet impregnated with aromatics similar to that of Example 1 was completed in 2 hours.

Claims (1)

[Claims] 1. A pellet-like product characterized in that the pellets of ethylene-vinyl acetate copolymer resin and the fragrance are brought into contact with each other under temperature conditions in which the pellets do not substantially fuse, thereby impregnating and absorbing the fragrance into the pellets. A method for producing a sustained release fragrance composition.