Note: Descriptions are shown in the official language in which they were submitted.
SLOWLY RELEASING PERFUME OOMPOSITIONS
Background of the Invention
The present invention relates to slo~Jly releasing
perfume compositions.
As slo~ly releasing perfume compositions mainly occupy-ing
the aromatic market at present there are so-called gel aromatics
comprising water-soluble gels such as agar and carrageenan and
perfumes dispersed therein using surfactants. Such gel aromatics
have a superior volatilization mechanism such that they slowly
release the perfumes dispersed therein along with gradual evaporation
of water, and they c~ be colored easily into beautiful colors.
Because of these superior characteristics, such gel aromatics
are relatively popular. However, such gel aromatics have various
drawbacks. For e~ample, they always require a solid container
as a protector for covering up the drawback of water-soluble gels
that the gels easily get out of shape when a physical external
force is exerted thereon; the amount of a perfume which can be
dispersed in the gel is at most 10% or so of the weight of the
gel9 therefore in order to be fully effective during the period
of use requlred of ordinary aromatics, namely, one to two months,
it i5 necessary to use a relatively large amount, 70 to 150 grams,
of a gel aromatic for each aromatic commodity; because the gel
used is a water-soluble gel, it easily freezes at a temperature
bel~w 0C and causes a phenomenon of water separation when thawing;
and because the gel surface hardens in the form of a film along
with evaporation of water, the effective volatlllzation percentage
of the perfume dlspersed in the gei is relatlvely small (35% or
so of the dispersed perfume on an average)~
There are also known various scented plastics comprlsing
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thermoplastic resins and small amounts of perfumes contained
therein~ Such scented plastics are obtained by adding a
perfume beforehand to a starting resin before molding followed
by melt-kneading under application of heat at a temperature
of about 150C to about 200C and then moldin~ the mixture by
a conventional molding me-thod. In such a method, however,
the hea-ting step causes volatilization of a low boiling por-
tion of the perfume and a quali-ta-tive -thermode-terioration,
thus resulting in that the fragrance of the resultant scented
molding is in many cases markedly different from that of the
perfume used, and in order to prevent such an inconvenience
it is inevitably required to restrict the perfume components
used to high boiling components difficult to underyo such
volatilization and thermal deterioration. Moreover, such
scented plastics are not considered to satisfy both intensity
and durability of fragrance.
_ummary of the Invention
It is an object of the present invention to provide
novel, slowly releasing perfume compositions which permit a
uniform volatilization of perfume over a long period of time.
It is another object of the present invention to pro-
vide novel, slowly releasing perfume compositions which do not
undergo swelling, softening, deforma-tion or the like even if
the perfume content thereof is relatively large.
In accordance with the present invention, -there is
-thus provided a slowly releasiny perfume composition comprising
a granulated ethylene-vinyl acetate copol~ner having a perEume
absorbed therein and containing granules of abou-t 1 to about
10 mm in diameter, the ethylene-vinyl ace-tate copolymer
containiny about 19 to about ~0% by weight of vinyl ace-ta-te
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and the perfume containing as an essential component at least
one fragrant component selected from the group consisting of
hydrocarbons and esters, the total amount of hydrocarbon(s)
and ester(s), in the perfume being not less than about 30%.
The perfume composition of the invention is prepared by mixing
the granulated copolymer and the perfume at a temperature in
the range of about 10C to about 50C to cause absorption of
the perfume in the granulated copolymer.
Detailed Description of the Invention
The ethylene-vinyl acetate copolymer used in the
present invention has a vinyl acetate content in the range of
19% to 40%, preferably 25% to 33%, by weight. If the vinyl
acetate content is lower than this range, a sub~tantial
absorption of perfume cannot be expected, and if it exceeds
this range, the resulting product will swell and soften
remarkably.
It is necessary that the ethylene-vinyl acetate co-
polymer used in the invention be preformed into granules
preferably having a spherical, cylindrical or like shape of a
diameter of about 1 to about 10 mm, particularly about 2 to
about 6 mm, although the shape of the granules is not limited
thereto.
The per-fume used in the presen-t invention contains as
an essential cornponent hydrocarbons and/or esters. As hydro-
carbons there rnay be exemplified monoterpene hydrocarbons such
as limonene, ~-pinene and ~-pinene, sesquiterpene hydro-
carbons such as caryophyllene, santalene, thujopsene and
cedrene, diterpene hydrocarbons such as abie-tin and camphorene,
and aroma-tic hydrocarbons such as p-cymene and styrene. As
esters there may be exernplified aliphatic and aromatic
carboxylic acid es-ters haviny usually not more than 20,
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preferably not more than 15, carbon atoms, such as isoamyl
acetate, geranyl acetate, citronellyl acetate, linalyl aceta-te,
benzyl aceta-te, benzyl benzoate, benzyl salicylate, cinnamyl
cinnamate, isoamyl undecylate and cedryl acetate.
The perfume used in the invention is u~ually a mixed
perfume and it is desirable that not less than 30%, par-ticular-
ly not less than 50%, of all the perfume components be
occupied by
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the hydrocarbons and/or esters as exemplified above. The perfume
may contain a fixative. ks the fixative it is also preferable
to use hydrocarbon and ester type fixatives.
If hydrocar~ons or esters are little contained as
a perf~e component~ a suEficient efEect of impregnation of the
perfume cannot be expected.
~ he operation for impregnation and absorption of the
perfume is carried out by m xing the perfume and ~he granulated
copolymer at a temperature in the range of about 10C to absut
50C. Operating temperatures higher than 50~C would cause a
change in quality of the perfume or other bad influence, and
if the operating temperature is too low9 it will be impossible
~o obtain a sufficient effect of a~sorption of the perfume.
In the mixing of the perfume and the granulated cDpolymer,
it is desirable that the perfume be used in an equivalent amount,
preferably in an amount ranging from about 5% to about 50% by weight,
based on the amount of the granulated copolymer, and that substantially
all the perfume present ln the system be impregnated and a~sorbed
into the granulated copolymer.
~0 ~le granulated ethylene-vlnyl acetate copolymer containing
the perfume thus obtained may increase ln its volume according to
the amount of the perfume impregnated and abso~bed therein, but
it will never exhibit a marked softening~ deformation, collapse
or ~he llke. besides, beca~e the perfume content is high as
previously noted, it is ~ufficient to use only a very ~mall amount
of 6uch perfume-impregnated granules in the caae of using the
granule~ as a volatlllzation matri~., and the granules can be put
to the use of aromatics and llke co}~modities by merely charging
or sealing lnto a ~i~ple and llght container ~uch as 3 for example,
a bag made of a non-woverl fabric or a pack of polyethylene fllm
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having a vent hole.
In this molded article, moreover, the perfume is
impregnated and absorbed -thereln in the form of a plasticizer
for resin or the like, so that its volatilization is slow and
durable, and as to its effective volatilization percentage, it
is possible to at-tain a very high value of not less than 50%.
Furthermore, the molded article can be colored
beautifully simultaneously with the impregnation and absorption
of the perfume easily by dissolving an oil-soluble coloring
matter of a desired color beforehand in the perfume.
The following are working examples of the present in-
vention, but it is to be understood that the vinyl aceta-te con-
tent of the granular ethylene-vinyl acetate copolyrners used
therein and the shape, etc. of the resultant molded articles
are not limited to those exemplified therein.
Example 1
70 g~ of transparent pellets (each being a spherical
body having a diameter of about 5mm) of an e-thylene-vinyl acetate
copolymer EVAFLEX-150 (tradernark, manufactured by Mi-tsui Poly-
chemical Co., vinyl acetate content 33%~ and 30 g. of a mixedlemon perfume (containing 32 wt.% of limonene and other hydro-
carbons) which had been yellowed with Oil yellow 3G were sealed
into an eggplant type flask (capacity: 2 liters) of a rotary
evaporator and the flask was rotated a-t a rate of ~0 r.p.m. In
about 20 minutes -the pelle-ts absorbed the perfume nearly comple-
tely. In this s-tage the surfaces of -the pellets were wet, so
the rotation was further continued, as a resul-t the perfume
penetrated into the pellets, -thus allowiny the surfaces of the
pellets to dry gradually, and after 1 hour there were obtained
perfume-containing pelle-ts
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having a good fluidity. The pellets were dry, translucen~ and
yellow.
10 g. of the perfume containing pellets were charged
into a bag made of a thin non-woven fabric and the bag thus charged
with the pellets was allowed to stand for 50 days within a flush
toilet (3.8 m3). The performance of the pellets as an aromatic
was evaluated by an organoleptic panel test, as a result, the
fragrance intensity during that period proved to be in the range
of 4 to 2.75 (according ~o the 6-stage odor indication method~.
After termina~ion of the above period, the volatilization
percentage of the perfume was determined. As a result, it proved
to be 58% Closs of weight 1.74g./amount of perfume impregnated
3g. x 100) and thus a very good result could be obtained.
Example 2
70 g. of transparent pellets (each being a spherical
body having a diameter of about 5 mm) of an et~ylene-vinyl acetate
copolymer "EVAFLEX-460" (manufactured by Mitsui Pol~chemlcal Co.,
vinyl acetate content 19%) and 30 g. of a mixed lemon perfume
(contalning 32 wt.% of limonene and other hydrocarbons) which
had been yellowed with Oil yell~w 3G were sealed into the flask
of the rotary evaporator in the same way as in Exa~ple 1 and
the flask w~s ro~ated a~ a rate of 30 r.p.m. while dipping the
lower surfaee of the flask ln a water bath held at 45~C. After
5 hour6, there were obtained perfume-impregnated pellets like
the pellets obtained in Example 1. The performance of the pellets
as an aroma~ic was ~us~ the ~ame as that evalua~ed ln Example 1.
Example 3
70 g. of transparent pellet3 of the "EvAFL~X~150"
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described in Example 1 and 30 g. of a mixed fragrant olive perfume
(containing 43% of esters such as ethyl acetate, amyl acetate,
amyl butyrate, ethyl caproate and benzyl acetate~ which had been
colored to orange color were sealed into the flask of the ro~ary
evaporator in the same way as in Example 1 and the flask was
rotated at a rate of 30 r.p~m. while dipping the lower surface
of the flask in a water ba~h held at 30~C. AEter 2 hours, there
were obtained perfume-impregnated pellets like the pellets o~tained
in Example 1. The performance of the pellets as an aromatic
was jus~ the same as that evaluated ln Example 1D
