Pressure sensitive transfer tape

Abstract: A pressure sensitive transfer tape (1) such as transfer-type pressure sensitive correction tape or transfer-type pressure sensitive adhesive tape that is used with being mounted in a handy-type transfer tool is provided which comprises a film support (2) comprising an organic polymer and a pressure sensitive transfer layer (3) on the film support (2), the pressure sensitive transfer layer (3) comprising at least a pressure sensitive adhesive layer, the support (1) having a first coefficient of kinetic friction on the transfer layer side of the support against a surface of an object (13) receiving the transfer and a second coefficient of kinetic friction on the rear side of the support against a head member of a transfer tool, the first coefficient of kinetic friction being larger than the second coefficient of kinetic friction, and a difference between the first coefficient of kinetic friction and the second coefficient of kinetic friction being not less than 0.01.

Description: The present invention relates to a pressure sensitive transfer tape such as a transfer-type pressure sensitive correction tape or a transfer-type pressure sensitive adhesive tape. More particularly, the invention relates to a transfer-type pressure sensitive correction tape wherein a pressure sensitive transfer layer, which is comprised of a masking layer and a pressure sensitive adhesive layer, is transferred onto a paper surface or a like surface by being pressed against the surface by means of a handy-type transfer tool such that an image comprising characters or the like residing on the spot is masked and thus erased, and wherein it is possible to write with a writing tool such as a ballpoint pen or a pencil on the surface of the transfer layer that has been transferred, and the invention further relates to a transfer-type pressure sensitive adhesive tape wherein a pressure sensitive adhesive layer is transferred onto an object receiving the transfer such as a paper surface by being pressed against the paper surface by means of a handy-type transfer tool such that other article can be pasted on the object receiving the transfer. In these days, transfer-type pressure sensitive correction tapes are being paid attention to instead of conventional correction liquids owing to their advantageous characteristics such as easiness of handling and ability of writing on corrected spots immediately after the correction. Known transfer-type pressure sensitive correction tapes of this type are those having a structure wherein a pressure sensitive transfer layer including a masking layer containing a white pigment and a pressure sensitive adhesive layer is provided on one side of a support. As the support, generally paper sheets such as glassine paper which have undergone a releasing treatment are used. Such transfer-type pressure sensitive correction tapes are used with being mounted in a handy-type transfer tool. Fig. 1 is a schematic view showing one example of a handy-type transfer tool in which a pressure sensitive correction tape is mounted, and Fig. 2 is an enlarged view of a main part thereof. 1 denotes a transfer-type pressure sensitive correction tape wherein a pressure sensitive transfer layer 3, which includes a masking layer and a pressure sensitive adhesive layer laminated in this order, on a support 2. Main components of the transfer tool comprises a supply reel 10 for the pressure sensitive correction tape 1, a winding reel 11 for the support 2, and a wedge-shaped head 12 for pressuring the pressure sensitive correction tape 1 onto an object receiving the transfer 13 such as a sheet of paper. It should be noted that a gear mechanism for driving the supply reel 10 and the winding reel 11, a cartridge for setting the supply reel 10 and the winding reel 11 to be mounted into the transfer tool and a case body are omitted in Figs. 1 and 2. When the transfer tool is moved on the object receiving the transfer 13 in a direction of arrow A, the pressure sensitive correction tape 1 is drawn out and pressed by the head 12 whereby the pressure sensitive transfer layer 3 is parted from the support 2 and adhered onto the object receiving the transfer 13. On the other hand, the support 2 that has been parted from the pressure sensitive transfer layer 3 is wound by the winding reel 11. Recently, downsizing is also a necessity for such transfer tools. Consequently, pressure sensitive correction tapes are also required to be reduced in thickness and width. However, conventional pressure sensitive correction tapes employing supports of paper can hardly cope with such requirements. In view of this fact, it has been proposed to employ an organic polymer film that has undergone a releasing treatment as the support. However, the following drawbacks were caused by the use of such an organic polymer film. First, slips are caused at the time of running the pressure sensitive correction tape owing to the fact that the support is a polymer film. That is, in case the pressure sensitive correction tape 1 is drawn out from a transfer tool while the support 2 at a portion of the head 12 is not provided with a pressure sensitive transfer layer 3 as shown in Fig. 2, a desired friction force with respect to a common object receiving the transfer (usual paper, etc.) can not be obtained since the polymer film is highly smooth. Thus, slip is generated at a usual pressing force so that the pressure sensitive correction tape 1 can not be drawn out. Hereinafter, the characteristics of the support that causes no slip is denoted to be favorable running characteristics of the support. The next problem exists in that the high smoothness of the polymer film results in a glossy surface of the transferred pressure sensitive transfer layer. That is, it can be easily understood that the interface of the masking layer, which is applied on a release layer, with the release layer which is applied on the polymer film also becomes highly smooth. When such a masking layer is transferred onto a paper sheet, the surface of the transferred masking layer will be glossy in contrast to the unglossy surface of the paper receiving the transfer which surface is of low smoothness so that the corrected portion which is originally not intended to stand out will be conspicuous. Hereinafter, the characteristics wherein the surface of the transferred masking layer is unglossy is denoted as "unglossiness". In order to solve the above problems, it may be considered to take measures for increasing the friction force with respect to the object receiving the transfer or for coping with unglossiness, such as incorporating particles into the polymer film or performing a sand matting treatment on one surface of the polymer film, but all of these measures result in higher costs. Further, transfer-type pressure sensitive adhesive tapes are also being paid attention to instead of double-sided adhesive tapes or stick-type glues in view of easiness of handling. Known transfer-type pressure sensitive adhesive tapes of this type are those having a structure wherein a pressure sensitive adhesive layer is provided on one side of a support. As the support, generally paper sheets such as glassine paper which have undergone a releasing treatment are used. Such transfer-type pressure sensitive adhesive tapes are used with being mounted in a handy-type transfer tool. Fig. 3 is a schematic view showing one example of a handy-type transfer tool in which a pressure sensitive adhesive tape is mounted, and Fig. 4 is an enlarged view of a main part thereof. 21 denotes a transfer-type pressure sensitive adhesive tape wherein a pressure sensitive adhesive layer 23 is provided on a support 22 as a pressure sensitive transfer layer. Main components of the transfer tool comprise a supply reel 10 for the pressure sensitive adhesive tape 21, a winding reel 11 for the support 22, and a wedge-shaped head 12 for pressuring the pressure sensitive adhesive tape 21 onto an object receiving the transfer 13 such as a sheet of paper. It should be noted that a gear mechanism for driving the supply reel 10 and the winding reel 11, a cartridge for setting the supply reel 10 and the winding reel 11 to be mounted into the transfer tool and a case body are omitted in Figs. 3 and 4. When the transfer tool is moved on the object receiving the transfer 13 in a direction of arrow A, the pressure sensitive adhesive tape 21 is drawn out and pressed by the head 12 whereby the pressure sensitive adhesive layer 23 is parted from the support 22 and adhered onto the object receiving the transfer 13. On the other hand, the support 22 that has been parted from the pressure sensitive adhesive layer 23 is wound by the winding reel 11. Recently, downsizing is also a necessity for such transfer tools. Consequently, pressure sensitive adhesive tapes are also required to be reduced in thickness and width. However, conventional pressure sensitive adhesive tapes employing supports of paper can hardly cope with such requirements. In view of this fact, it has been proposed to employ an organic polymer film that has undergone a releasing treatment as the support. However, the use of such an organic polymer film causes slips at the time of running the pressure sensitive adhesive tape owing to the fact that the support is a polymer film. That is, in case the pressure sensitive adhesive tape 21 is drawn out from a transfer tool while the support 22 at a portion of the head 12 is not provided with a pressure sensitive adhesive layer 23 as shown in Fig. 4, a desired friction force with respect to a common object receiving the transfer (usual paper, etc.) can not be obtained since the polymer film is highly smooth. Thus, slip is generated at a usual pressing force so that the pressure sensitive adhesive tape 21 can not be drawn out. In order to solve the above problems, a roller head is being used as the head of the transfer tool. Further, it may be considered to take measures for increasing the friction force with respect to the object receiving the transfer, such as incorporating particles into the polymer film or performing a sand matting treatment on one surface of the polymer film. However, all of these measures result in higher costs. As described above, accompanying desires for downsizing of transfer tools and longer transfer-type pressure sensitive correction tapes or adhesive tapes, transfer-type pressure sensitive correction tapes or adhesive tapes are being required to be reduced in thickness. For thinning of transfer-type pressure sensitive correction tapes or adhesive tapes, one may consider to employ thin supports. However, a lower limit-for the thickness is approximately 30 µm in view of strength in case of glassine paper which is generally used in conventional tapes. It has then been proposed to employ an organic polymer film as the support. However, the present inventors have discovered that simple use of a thin organic polymer film may lead to degradation in transferability so that such a film is practically not suitable for use. The term "transferability" of transfer-type pressure sensitive correction tapes or adhesive tapes denotes characteristics wherein a desired length of the transfer layer onto which pressure is applied with being drawn out from the transfer tool is completely transferred and wherein the portion of the transfer layer transferred are easily cut off from the remaining portion when a larger pressure is applied at the time when the transfer operation is finished so that no undesired portions are transferred. EP-A-0 733 483 describes a pressure-activated marking tape having a carrier and an adhesive coloring layer coated on the carrier. The coefficient of static friction of the surface of the coloring layer adhered on the substrate is preferably from 0.2 to 8. EP-A-0 479 221 describes a transfer tape for masking correction comprising a film-like foundation and a pressure-transferable masking layer. Preferably, one or both surfaces of the foundation are coated with a releasing agent such as silicones and fluorine-containing resins for the purposes of preventing the adhesive layer from adhering to the back surface of the foundation during storage or facilitating the peeling of the masking transfer layer from the foundation. For the foundation a polyethylene teraphthalate (PET) film may be used. DE-C-41 17 404 describes a method for applying an adhesive film provided on a support to a object using a transfer tool. In view of the above facts, it is an object of the present invention to provide a compact-type pressure sensitive transfer tape such as a transfer-type pressure sensitive correction tape or transfer-type pressure sensitive adhesive tape which presents favorable running characteristics of a support at low costs. It is another object of the present invention to provide a pressure sensitive transfer tape such as a transfer-type pressure sensitive correction tape or transfer-type pressure sensitive adhesive tape which further presents favorable transferability in spite of employing a thin organic polymer film as a support. The present invention provides a pressure sensitive transfer tape comprising a film support comprising an organic polymer and a pressure sensitive transfer layer on the film support as defined in claim 1, the pressure sensitive transfer layer comprising at least a pressure sensitive adhesive layer, the support having a first coefficient of kinetic friction on the transfer layer side of the support against a surface of an object receiving the transfer and a second coefficient of kinetic friction on the rear side of the support against a head member of a transfer tool, the first coefficient of kinetic friction being larger than the second coefficient of kinetic friction , and a difference between the first coefficient of kinetic friction and the second coefficient of kinetic friction being not less than 0.01. The present invention provides the pressure sensitive transfer tape wherein the support has respective release layers on both sides thereof and wherein the release layer on the transfer layer side contains not less than 1 % by weight of inorganic or organic particles having an average particle size of 0.3 to 5 µm. The present invention further provides the pressure sensitive transfer tape according to the above wherein the pressure sensitive transfer layer has a laminated structure comprising a masking layer and a pressure sensitive adhesive layer laminated in this order from the support side. The present invention further provides the pressure sensitive transfer tape according to the above wherein the pressure sensitive transfer layer comprises the pressure sensitive adhesive layer alone. The present invention further provides the pressure sensitive transfer tape according to the above wherein the following relationships are satisfied: Y ≦ 25 µm X/Y ≧ 1 wherein Y denotes a thickness of the support and X a thickness of the pressure sensitive transfer layer. The present invention further provides the pressure sensitive transfer tape according to the above wherein the pressure sensitive transfer layer has a laminated structure comprising a masking layer and a pressure sensitive adhesive layer laminated in this order from the support side. Fig. 1 is a schematic view showing an example of a handy-type transfer tool in which a transfer-type pressure sensitive correction tape according to one embodiment of the present invention is mounted. Fig. 2 is an enlarged view of a main portion of the transfer tool as shown in Fig. 1. Fig. 3 is a schematic view showing another example of a handy-type transfer tool in which a transfer-type pressure sensitive adhesive tape according to another embodiment of the present invention is mounted. Fig. 4 is an enlarged view of a main portion of the transfer tool as shown in Fig. 3. The pressure sensitive transfer tape according to the present invention has a structure wherein a pressure sensitive transfer layer comprising at least a pressure sensitive adhesive layer as an uppermost layer thereof is provided on a film support comprising an organic polymer. The pressure sensitive transfer tape of the present invention includes a transfer-type pressure sensitive correction tape having a structure wherein a pressure sensitive adhesive layer comprising a masking layer and a pressure sensitive adhesive layer laminated in this order is provided on the film support comprising an organic polymer and a transfer-type pressure sensitive adhesive tape having a structure wherein a pressure sensitive transfer layer comprising a pressure sensitive adhesive layer alone is provided on the film support comprising an organic polymer. The present inventors have made intensive studies for eliminating slips at the time of drawing out the film support of the transfer-type pressure sensitive correction tape or adhesive tape and discovered that such slips can be eliminated by using a film support having a first coefficient of kinetic friction on the transfer layer side of the support against a surface of an object receiving the transfer and a second coefficient of kinetic friction on the rear side of the support against a head member of a transfer tool wherein the first coefficient of kinetic friction is larger than the second coefficient of kinetic friction and a difference between the first coefficient of kinetic friction and the second coefficient of kinetic friction is not less than 0.01. The present inventors have also discovered that the coefficient of kinetic friction against usual paper can be increased by providing respective release layers on both sides of the film support and incorporating inorganic or organic particles in the release layer on the transfer layer side such that the release layer assumes an uneven surface, as a means for providing a difference between coefficients of kinetic friction against respective objects on the front and rear sides of the film support. Since a treatment for matting the support is not required in such cases, products can be offered at low costs. It should be noted that it is possible to provide a difference in coefficient of kinetic friction between the front and rear sides by using respective releasing agents having different slip characteristics on the front and rear sides as a means for providing a difference between coefficients of kinetic friction against respective objects on the front and rear sides of the film support. However, this is not necessarily a favorable means since a treatment for matting the film support itself needs to be performed to secure unglossiness of the pressure sensitive transfer layer in case of a transfer-type pressure sensitive correction tape such that costs for the support are increased and products can thus not been offered at low costs. In the transfer-type pressure sensitive correction tape of the present invention, both an increase in coefficient of kinetic friction against usual paper as well as unglossiness of the transferred transfer layer can be achieved by providing respective release layers on both sides of the film support and incorporating inorganic or organic particles in the release layer on the transfer layer side such that the surface of the release layer assumes an uneven surface as a means for providing a difference between coefficients of kinetic friction to respective objects on the front and rear sides of the film support. The inventors have further made intensive studies for coping with problems arising when employing a thin organic polymer film as a support. In case a pressure sensitive transfer tape such as a transfer-type pressure sensitive correction tape or adhesive tape is mounted in a handy-type transfer tool for performing transfer, it may be considered that it be sufficient to use a thin support film for improving the transferability by effectively transmitting the pressurizing force of the head to the transfer layer via the support film. It was actually the case that the transferability could not be improved so much even by using a thin organic polymer film simply but was rather degraded. However, it has been unexpectedly discovered that the transferability could be remarkably improved in case the thickness Y of the organic polymer film is set to be not more than 25 µm while maintaining a relationship of X/Y ≧ 1 for the thickness Y of the organic polymer film (in case a release layer is provided on the organic polymer film, the thickness Y means a total thickness of the organic polymer film and the release layer) and thickness X of the pressure sensitive transfer layer (i.e. a laminated structure of the masking layer and pressure sensitive adhesive layer in case of a transfer-type pressure sensitive correction tape, and the pressure sensitive adhesive layer in case of a transfer-type pressure sensitive adhesive tape). While the reason for this is not quite evident, it is assumed that the balance between the cushioning characteristics owned by the transfer layer and the rigidity of the organic polymer film is important in case of performing transfer by pressing the transfer tape through the head, and that a favorable balance can be achieved in case X and Y satisfy the above relationship. Thus, since it is possible to employ an organic polymer film having a thickness of not more than 25 µm as a support, downsizing of transfer tools and use of long transfer tapes can be achieved. The present invention will now be explained in detail. In the present invention, a support comprising an organic polymer film and respective release layers on both sides of the organic polymer film wherein particles having an average particle size of 0.3 to 5 µm are contained in the release layer on the side in contact with a pressure sensitive transfer layer ( a masking layer in a pressure sensitive transfer layer in case of a transfer-type pressure sensitive correction tape, and a pressure sensitive adhesive layer in case of a transfer-type pressure sensitive adhesive tape) is used. With such a structure, it is easy to make a coefficient of kinetic friction on the transfer layer side of the support against a surface of an object receiving the transfer to be larger than a coefficient of kinetic friction on the rear side of the support against a head of a transfer tool and to make a difference between the coefficients of kinetic friction to be not less than 0.01, resulting in excellent running characteristics of the support. In addition, excellent unglossiness can be obtained in case of transfer-type pressure sensitive correction tapes. It should be noted that although an upper limit for the difference between the coefficient of kinetic friction on the transfer layer side of the support against the surface of the object receiving the transfer and the coefficient of kinetic friction on the rear side of the support against the head of the transfer tool is not particularly limited, generally it is approximately 0.50. The coating amount (on a dry weight basis, hereinafter the same) of the release layer on the side contacting the pressure sensitive transfer layer is preferably about 0.1 to 2.0 g/m 2 . An average particle size for the inorganic or organic particles that are added into the release layer is in the range of 0.3 to 5 µm. In case the average particle size is less than 0.3 µm, an effect of making the surface of the release layer uneven is hardly achieved. On the other hand, in case the average particle size is larger than 5 µm, such an effect is remarkable but drawbacks are presented wherein it becomes difficult to disperse particles uniformly in the release layer or particles come easier off the release layer. Examples of the particles include inorganic particles such as silica, zirconia and titanium oxide, and organic particles such as particles of melamine resin and particles of high molecular weight polyethylene wax, while they are not particularly limited. The content of inorganic or organic particles in the release layer is not less than 1 % by weight, more preferably in the range of 1 to 45 % by weight. In case the content of particles is less than 1 % by weight, the effect of making the surface of the release layer uneven can not be sufficiently displayed. On the other hand, in case the content exceeds 45 % by weight, original functions of the release layer are lost and deficiencies in adhesion of the release layer to the support or deficiencies in peeling of the masking layer from the release layer tend to be generated. Examples of releasing agents used for the release layer include silicone resins, fluorine-containing resins and waxes. Among these, silicone resins are preferably used. As for the release layer on the rear side of the support, a release layer similar to the release layer on the side contacting the transfer layer except that no particles are incorporated may be used. As the organic polymer film, films having a thickness of approximately 5 to 100 µm are preferably used. Films having a thickness of 6 to 25 µm are more preferably used. In case the thickness is less than 5 µm, a sufficient strength is not exhibited in case the film is processed into a tape-like shape so that the film is unsuitable for practical use. On the other hand, in case the thickness exceeds 100 µm, compactness can not be achieved and inconveniences may occur at the time of processing. In view of transferability, a film having a thickness of not more than 25 µm is particularly preferable, and in view of compactness, a film having a thickness of not more than 20 µm is preferably used. The material for the film is a polyester, in particular polyethylene terephthalate (PET). In case of a transfer-type pressure sensitive correction tape according to the present invention, a masking layer and a pressure sensitive adhesive layer are provided in this order on the release layer of the film support that contains particles . The masking layer is comprised of a masking agent and a polymer having rubber elasticity as a binder. Preferable polymers having rubber elasticity are those presenting flexibility though containing only a small amount of plasticizer. Examples of such polymers are, for instance, styrene polymers, polyurethane rubbers, fluorine containing rubbers, acrylonitrile-butadiene rubber, ethylene-vinyl acetate copolymer, ethylene-alkyl acrylate copolymer, chlorosulfonated polyethylene and cyclized rubber. These polymers may be used either singly or in a combination of two or more of them in view of transferability. Preferred polymers having rubber elasticity are styrene polymers. Examples of styrene polymers are, for instance, styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene rubber, styrene-isoprene-styrene block copolymer (SIS) and styrene-ethylene/propylene block copolymer (SEP). Such styrene polymers may be used either singly or in a combination of two or more of them. As for the binder for the masking layer, a resin may be used in combination with the polymer having rubber elasticity. By the addition of resin, improvements in cutting-off characteristics of the masking layer and adjustments of hardness of the masking layer are enabled. Such resins preferably have a small elongation percentage, a melting or softening point of not less than 100°C, and a high hardness. Examples of specific resins are, for instance, hydrocarbon resins (preferably saturated or unsaturated alicyclic hydrocarbon resins), styrene-acryl copolymer, ketone resins, vinyl chloride-vinyl acetate copolymer, and polyolefin resins such as polyethylene or polypropylene. These resins may be either used singly or in a combination of two or more of them. In case of a transfer-type pressure sensitive correction tape, it is desired that further requirements are favorably accomplished in addition to the transferability, for instance, that no cracks occur in the transfer layer when the transfer layer is transferred onto a desired spot (hereinafter referred to as "crack resistance") and that it is possible to write on the transferred transfer layer with a writing tool such as a pencil or a ballpoint pen (hereinafter referred to as "writability"). It is preferable that the composition of the masking layer according to the present invention be suitably selected such that favorable crack resistance and writability are exhibited in addition to favorable transferability. In view of this point, the binder to be used for the masking layer according to the present invention preferably has an elongation percentage of not less than 3.5 × 10 2 % (a measured value at ordinary temperature in accordance with the testing method of ASTM D-412, hereinafter the same ). In case the elongation percentage is less than 3.5 × 10 2 %, the crack resistance tends to be degraded or a partial transfer failure tends to occur. The upper limit for the elongation percentage of the binder is generally 5.2 × 10 2 %. The binder for the masking layer comprises one or more polymers having rubber elasticity so that they are used either singly or in a combination of two or more of them so as to satisfy the aforesaid elongation percentage. A more preferable binder is a combination of one or more of the aforesaid polymers having rubber elasticity and one or more of the aforesaid resins, especially a combination of one or more of polymers having rubber elasticity with an elongation percentage of not less than 4.5 × 10 2 % and one or more of resins having an elongation percentage of not more than 50 %. In case the polymer having rubber elasticity and resin are used in combination, the mixing ratio thereof may vary depending upon the elongation percentages of the polymer having rubber elasticity and resin. However, the mixing ratio is preferably selected so that the elongation percentage of the resulting binder is not less than 3.5 × 10 2 %. Use of a combination of a polymer having rubber elasticity with an elongation percentage of not less than 4.5 × 10 2 % and a resin having an elongation percentage of not more than 50 % can provide a binder which imparts the masking layer with more excellent flexibility, writability and cutting-off characteristics. A typical mixing ratio is in a range of 2 to 30 parts (parts by weight, hereinafter the same), preferably 5 to 15 parts of a resin, with respect to 10 parts of a polymer having rubber elasticity. A binder containing the polymer and the resin in such a mixing ratio exhibits suitable elasticity and is capable of forming a masking layer that is superior in writability after transfer. In case the proportion of the resin exceeds the above range or in case the binder is composed of the resin alone, the resulting masking layer is poor in flexibility and cracks are apt to occur at the time of transfer. In case the proportion of the resin is less than the above range, the resulting masking layer is poor in writability as well as cutting-off characteristics of the masking layer is degraded. The cutting-off characteristics is further degraded in case the binder is comprised of the polymer having rubber elasticity alone. In view of obtaining favorable cutting-off characteristics, the masking layer is preferably of a porous structure. To this end, a filler is generally incorporated into the masking layer. Examples of such fillers are, for instance, magnesium carbonate, calcium carbonate, barium carbonate, barium sulfate, aluminum oxide, silicon dioxide, sellaite, clay and talc. The particle size of the filler is preferably in the range of 1 to 20 µm. In case the particle size is too small, the cutting-off characteristics is degraded whereas a too large particle size tends to cause degradation in writability. The filler is preferably mixed in an amount of 5 to 40 parts, more preferably 5 to 18 parts, with respect to 10 parts of the binder. In case that the proportion of the filler is too large, chalking phenomenon is caused and in case that the proportion of the filler is too small or no filler is used, the cutting-off characteristics of the masking layer tends to be degraded. Since the object to be subjected to correction operation using the pressure sensitive correction tape of the present invention is generally white paper, the masking layer is generally colored white by using a white masking agent. However, in case the object is a paper sheet or a like article that is colored to assume a color other than white, it is preferable that the masking layer be colored to assume substantially the same color as the background color of the object such that masked portions can not be distinguished from remaining background portions and do not stand out. As for the white masking agent, titanium oxide is mainly used owing to its superior hiding power. Masking agents other than of white color that may be used in the present invention are inorganic pigments such as Titanium Yellow, iron oxide pigments, Ultramarine Blue, Cobalt Blue, Chromium Oxide Green, Spinel Green, Chrome Yellow, Chrome Vermilion, Cadmium Yellow, Cadmium Red and aluminum powder, and organic pigments such as azo lake pigments, Hanza pigments, benzimidazolone pigments, monoazo pigments, diarylide pigments, pyrazolone pigments, condensed azo pigments, phthalocyanine pigments, quinacridone pigments, perylene pigments, perinone pigments, dioxazine pigments, anthrachinone pigments and isoindolinone pigments. The amount of the masking agent used is preferably 5 to 40 parts, more preferably 10 to 20 parts with respect to 10 parts of the binder though it varies depending upon the dispersibility and hiding power of the masking agent used. In case the amount of the masking agent is excessive, chalking phenomenon in which masking agent powder bleeds out onto the masking layer surface occurs, and in case the amount of the masking agent is too small, the hiding power may be insufficient. The masking layer may contain additives such as dispersing agents in addition to the above components. The thickness (which indicates the thickness after drying, hereinafter the same) of the masking layer is preferably in the range of 10 to 40 µm, more preferably 12 to 30 µm. In case the thickness is less than the above range, the masking layer is insufficient in hiding power. On the other hand, in case the thickness exceeds the above range, cutting-off characteristics at the time of transfer or writability after transfer tend to be degraded. Further, when a copy of a paper sheet masked with the masking layer is taken, boundary portions between masked portions and unmasked portions of the paper sheet are copied as shades so that the obtained copy is undesirable. The pressure sensitive adhesive layer is a coating layer of a pressure-sensitive adhesive Examples of such pressure sensitive adhesives include acrylic resin based adhesives, rosin based adhesives, rubber based adhesives, vinyl ether resin based adhesives and polyisobutylene based adhesives. The pressure sensitive adhesive layer can be formed by applying a solution or dispersion of the adhesive in an organic solvent or an aqueous solution or dispersion (inclusive of emulsion) of the adhesive onto the masking layer and drying thereafter. The thickness of the pressure sensitive adhesive layer is preferably in the range of 0.8 to 5 µm, more preferably in the range of 0.8 to 3 µm. In case of the transfer-type pressure sensitive adhesive tape of the present invention, a pressure sensitive adhesive layer is formed on the release layer of the aforesaid film support that contains particles therein. While the pressure sensitive adhesive layer of the transfer-type pressure sensitive adhesive tape may be similar to the pressure sensitive adhesive layer of the aforesaid transfer-type pressure sensitive correction tape, a suitable thickness thereof is in the range of approximately 10 to 40 µm. In a preferred embodiment of the present invention, the thickness X of the pressure sensitive transfer layer (i.e. a laminated structure of masking layer and pressure sensitive adhesive layer in case of a transfer-type pressure sensitive correction tape, and a pressure sensitive adhesive layer in case of a transfer-type pressure sensitive adhesive tape) and the thickness Y of the support preferably satisfy the following relationships: Y ≦ 25 µm X/Y ≧ 1 whereby favorable transferability can be obtained. Here, the thickness Y of the support denotes a thickness including the thickness of the release layer. In case the release layer contains particles therein, the thickness of the release layer is a thickness of portions where no particles protruding from the surface of the release layer are present. The pressure sensitive transfer tape (transfer-type pressure sensitive correction tape and transfer-type pressure sensitive adhesive tape) of the present invention is used with being mounted in a handy-type transfer tool (for instance, those as shown in Figs. 1 to 2 and Figs. 3 to 4). Upon use thereof, slip of the support is prevented by making the difference between the coefficient of kinetic friction of the transfer layer side of the film support against the surface of the object receiving the transfer and the coefficient of kinetic friction of the rear side of the film support against the head of the transfer tool to be not less than 0.01, so that the pressure sensitive transfer tape can be drawn out smoothly. In case of the transfer-type pressure sensitive correction tape, superior unglossiness of the surface of the transferred pressure sensitive transfer layer can be further exhibited. The unglossiness of the surface of the transferred pressure sensitive transfer layer is preferably not more than 35 in terms of gloss. In case the gloss is not more than 35, no particular incompatibility is observed on the object receiving the transfer such as paper. Usual paper (plain paper) which is a typical object receiving the transfer for pressure sensitive transfer tapes assumes a surface that is fairly uneven, and in order to achieve high friction with such paper, it is effective that the support of the transfer tape also assumes a surface that is uneven rather than smooth whereby the contact area can be increased. In the present invention, friction force with the object receiving the transfer (usual paper, etc.) is increased by making the release layer surface uneven through inorganic or organic particles contained in the release layer of the support on the side contacting the pressure sensitive transfer layer such that favorable running characteristics of the support can be obtained. The material for the head of the transfer tool comprises a polyacetal. By suitably selecting materials for the object receiving the transfer and materials for the head, the respective coefficients of kinetic friction on both surfaces of the support are set to desired values. The pressure sensitive adhesive tape of the present invention is suitably utilized in a transfer tool having a wedge-shaped head owing to the superior running characteristics of the support. The present invention will be more fully described by way of Examples. It is to be understood that the present invention is not limited to these Examples, and various changes and modifications may be made in the invention without departing from the spirit and scope thereof. EXAMPLE 1 Releasing treatment of support A release layer was formed by applying and drying a silicone resin-containing liquid of the following composition on one side of a PET film having a thickness of 12 µm such that the coating amount after drying became 0.5 g/m 2 (thickness: 0.5 µm). Composition of silicone resin-containing liquid Component Parts by weight Silicone resin (KS-3502, manufactured by 20 Shin-Etsu Silicone Co., Ltd.) Platinum catalyst 0.2 Toluene 40 Xylene 40 Silica (average particle size: 1.5 µm) 0.2 A composition similar to the above silicone resin-containing liquid except for the absence of silica particles was applied onto a rear surface of the PET film such that the thickness after drying became 0.5 µm and dried thereafter to form a release layer on the rear side. Manufacture of transfer tape A white pigment ink of the following composition was applied onto the particles-containing release layer of the above support such that the thickness after drying became 20 µm and dried thereafter to form a masking layer. Onto the masking layer was applied an acrylic resin based adhesive such that the thickness after drying became 1 µm and dried thereafter to form a pressure sensitive adhesive layer, yielding an original web for transfer-type pressure sensitive correction tape. Composition of white pigment ink Component Parts by weight Hydrocarbon resin (elongation percentage: 0 %) 5 SEBS copolymer (elongation percentage: 750 %) 5 Dispersing agent 2 Titanium oxide 30 Aluminum powder 0.2 Toluene 57 The original web for pressure sensitive correction tape obtained above was slit into 5 mm-wide tapes and, at the same time, each tape having a length of 10 m was wound around a core to obtain a sample in a pancake form. The pancake sample was mounted in a commercially available handy-type transfer tool (having a structure as shown in Figs. 1 to 2) to obtain a pressure sensitive correction tape transfer tool. EXAMPLES 2 to 3 and COMPARATIVE EXAMPLES 1 to 3 The same procedures as in Example lexcept that the content of silica particles in the release layer on the side contacting the masking layer was changed to values as shown in Table 1 were repeated to give original webs for pressure sensitive correction tape, from which pancakes were produced. Each pancake was mounted in a transfer tool to yield pressure sensitive correction tape transfer tools. In Comparative Example 3, glassine paper having a thickness of 40 µm was used as a support. Coefficients of kinetic friction of the supports were measured and performances of the pressure sensitive correction tapes were evaluated according to the following methods. The results are shown in Table 1. Method for measuring coefficients of kinetic friction A tester for measuring sliding properties manufactured by FUJICOPIAN CO., LTD. was employed. Each of the supports was sampled to assume a width of 5 mm and a length of approximately 20 cm and the sample was adhered onto a table of the tester. An object (PPC paper sheet) was adhered to a rod made of a resin and having a diameter of 3 mm and a rod having a diameter of 3 mm was formed of another object (polyacetal). The thus obtained item was brought in contact with the support in a horizontal manner and allowed to slide on the support with a load of 500 g being applied to the contact surface at a speed of 300 mm/min. The coefficient of kinetic friction was calculated from the obtained sliding resistance value. A PPC paper sheet was used as the object receiving the transfer and polyacetal was used as the material for the head of the transfer tool. Evaluation of the running characteristic of the support The pressure sensitive correction tape transfer tool was ran on the PPC sheet under a condition wherein the transfer layer was peeled off from the tape at the head portion as shown in Fig. 2. Cases in which the pressure sensitive correction tape could be easily drawn out by running the transfer tool were indicated by o ○, cases in which the pressure sensitive correction tape could be drawn out by running the transfer tool were indicated by ○, and cases in which some great force was necessary to draw out the pressure sensitive correction tape by running the transfer tool were indicated by ×. The higher the coefficient of kinetic friction of the support against the PPC paper sheet is, the more favorable the running characteristic of the support becomes. Evaluation of unglossiness Using the pressure sensitive correction tape transfer tool, the transfer layer was transferred onto a PPC sheet under a transfer load of 500 g and gloss of the surface of the transfer layer transferred was measured. Measuring device employed: Gloss Meter Model GM-26D (manufactured by Kabushiki Kaisha Murakami Shikisai Kagaku Kenkyusho) Measuring condition: 60 degrees gloss measurement (according to JIS Z 8741) The lower the measured value is, the more favorable the unglossiness is. It is preferable that the gloss value be not more than 35. As it is evident from the results as shown in Table 1, required characteristics such as running characteristic of the support or unglossiness could be secured in case the content of particles in the release layer on the side contacting the masking layer was in the range of 1 to 40 % by weight (Examples 1 to 3). In case the content of particles was less than 1 % by weight, a fairly great load was required to draw out the support and unglossiness of the transfer layer transferred could not be secured (Comparative Examples 1 to 2). While characteristics required for the support could be secured in case the support was of glassine paper (thickness 40 µm), it could not be secured for satisfactory strength in case the support was made thin (e.g. approximately 20 µm) owing to the fact that it was made of paper. EXAMPLE 4 Releasing treatment of support A release layer was formed by applying and drying a silicone resin-containing liquid of the following composition on one side of a PET film having a thickness of 12 µm such that the coating amount after drying became 0.5g/m 2 (thickness: 0.5 µm). Composition of silicone resin-containing liquid Component Parts by weight Silicone resin (KS-3502, manufactured by Shin-Etsu Silicone Co., Ltd.) 20 Platinum catalyst 0.2 Toluene 40 Xylene 40 Silica (average particle size: 0.5 µm) 0.2 A composition similar to the above silicone resin-containing liquid except for the absence of silica particles was applied onto a rear surface of the PET film such that the thickness after drying became 0.5 µm and dried thereafter to form a release layer on the rear side. Manufacture of pressure sensitive adhesive tape Onto the particles-containing release layer of the obtained support was applied an acrylic resin based adhesive such that the thickness after drying became 15 µm and dried thereafter to form a pressure sensitive adhesive layer, yielding an original web for transfer-type pressure sensitive adhesive tape. The original web for transfer-type pressure sensitive adhesive tape obtained above was slit into 5 mm-wide tapes and, at the same time, each tape having a length of 10 m was wound around a core to obtain a sample in a pancake form. The pancake sample was mounted in a commercially available handy-type transfer tool (having a structure as shown in Figs. 3 to 4) to obtain a transfer-type pressure sensitive adhesive tape transfer tool. EXAMPLES 5 to 6 and COMPARATIVE EXAMPLES 4 to 6 The same procedures as in Example 4 except that the content of silica particles in the release layer on the side contacting the pressure sensitive adhesive layer was changed to values as shown in Table 2 were repeated to give original webs for transfer-type pressure sensitive adhesive tape, from which pancakes were produced. Each pancake was mounted in a transfer tool to yield transfer-type pressure sensitive adhesive tape transfer tools. In Comparative Example 6, glassine paper having a thickness of 40 µm was used as a support. Coefficients of kinetic friction of the supports were measured according to the same measuring method as already described and performances of the transfer-type pressure sensitive adhesive tapes were evaluated according to the following method. The results are shown in Table 2. Evaluation of the running characteristic of the support The transfer-type pressure sensitive adhesive tape transfer tool was ran on the PPC sheet under a condition wherein the pressure sensitive adhesive layer was peeled off from the tape at the head portion as shown in Fig. 4. Cases in which the pressure sensitive adhesive tape could be easily drawn out by running the transfer tool were indicated by o ○, cases in which the pressure sensitive adhesive tape could be drawn out by running the transfer tool were indicated by ○, and cases in which some great force was necessary to draw out the pressure sensitive adhesive tape by running the transfer tool were indicated by ×. The higher the coefficient of kinetic friction of the support against the PPC paper sheet is, the more favorable the running characteristic of the support becomes. As it is evident from the results as shown in Table 2, required characteristics such as running characteristic of the support could be secured in case the content of particles in the release layer on the side contacting the pressure sensitive adhesive layer was not less than 1 % by weight (Examples 4 to 6). In case the content of particles was less than 1 % by weight, a fairly great load was required to draw out the support (Comparative Examples 4 to 5). While characteristics required for the support could be secured in case the support was of glassine paper (thickness 40 µm), it could not be secured for satisfactory strength in case the support was made thin (e.g. approximately 20 µm) owing to the fact that it was made of paper. EXAMPLE 7 A masking layer of the following composition was formed on one side of each of the supports as shown in Table 4. Component Parts by weight Titanium oxide (particle size: 0.1 to 1 µm) 50.0 Magnesium carbonate (particle size: 1 to 10 µm) 19.0 SEBS copolymer (elongation percentage: 750 %) 14.0 Alicyclic saturated hydrocarbon (elongation percentage: 0 %) 14.0 Dispersing agent (HOMOGENOL L-18) 3.0 Elongation percentage of binder: 370 % That is, 100 parts of the total amount of the above materials and 163 parts of toluene were mixed in a dispersing apparatus for 20 minutes to prepare a coating liquid. This was applied onto one side of each support by means of a coating machine and dried thereafter to form a masking layer. Thereafter, an aqueous dispersion (solid content: 20 % by weight) of an acrylic resin based adhesive was applied onto the masking layer and dried to form a pressure sensitive adhesive layer, yielding a transfer-type pressure sensitive correction tape. The thickness of the masking layer and the pressure sensitive adhesive layer as well as the total thickness of both are indicated in Table 3. Types of the supports employed were as indicated in Table 4. By combining types of supports, the thickness Y and the total thickness X of the masking layer and the pressure sensitive adhesive layer, total 35 types of original webs for transfer-type pressure sensitive correction tape were obtained. Each of the original webs for transfer-type pressure sensitive correction tape was slit into 5 mm-wide tapes and, at the same time, each tape having a length of 10 m was wound around a core to obtain a correction tape in a pancake form. Each of the correction tapes in a pancake form was mounted in a commercially available handy-type transfer tool (having a structure as shown in Figs. 1 to 2) for performing running test over the whole length (10 m) to check whether failure in transfer onto high quality paper could occur or not, and evaluation of transferability was performed according to the following standards. The results are shown in Table 4. ○ No failure in transfer occurs X Failure in transfer occurs Masking layer (µm) Pressure sensitive adhesive layer (µm) Total thickness (µm) 8.8 1.2 10 13.8 1.2 15 18.8 1.2 20 23.8 1.2 25 28.8 1.2 30 It can be understood from the results as shown in Table 4 that no failure in transfer occurs and favorable transferability is exhibited in case the thickness Y of the PET film is not more than 25 µm while maintaining a relationship of X/Y ≧ 1 between the thickness Y of the PET film and the total thickness X of the masking layer and pressure sensitive adhesive layer. EXAMPLE 8 A release layer containing particles therein and having a thickness of 0.5 µm was formed by applying and drying a coating liquid of the following composition onto one side of a PET film having a thickness of 12 µm. Component Parts by weight Silicone resin 25.0 Silica particles (average particle size: 1.5 µm) 0.5 Toluene 37.5 Xylene 37.5 A composition similar to the above coating liquid except for the absence of silica particles was applied onto a rear surface of the PET film, and dried thereafter to form a release layer having a thickness of 0.5 µm on the rear side. Thereafter, a masking layer having a thickness of 23.8 µm and a pressure sensitive adhesive layer having a thickness of 1.2 µm were formed on the particles-containing release layer of the support in the same manner as in Example 7 to obtain an original web for transfer-type pressure sensitive correction tape. A correction tape in a pancake form was obtained from the thus obtained original web for transfer-type pressure sensitive correction tape in the same manner as in Example 7 and the same was mounted in a commercially available transfer tool for performing transfer onto high quality paper (PPC paper). It was found that favorable running characteristic of the support were exhibited so that the pressure sensitive correction tape could be easily drawn out, that no failure in transfer occurred, that excellent transferability was exhibited and that no glossiness of transferred portions were observed to show any incompatibilities. According to the present invention, it has been enabled to provide a transfer-type pressure sensitive correction tape at low cost which employs a film support and exhibits both favorable running characteristic of the support and unglossiness. Consequently, it could be realized for thinning of supports and compactness of transfer-type pressure sensitive correction tapes. According to the present invention, it has also been enabled to provide a transfer-type pressure sensitive adhesive tape at low cost which employs a film support and exhibits superior running characteristic of supports. Consequently, it could be realized for thinning of supports and compactness of transfer-type pressure sensitive adhesive tapes. Further, by employing an organic polymer film having a thickness of not more than 25 µm as a support and maintaining a relationship of X/Y ≧ 1 between the thickness Y of the support and thickness X of the pressure sensitive transfer layer, superior transferability can be obtained.

Claims: A pressure sensitive transfer tape (1;21) comprising a polyethylene terephthalate (PET) film support (2;22) and a pressure sensitive transfer layer (3;23) on the film support (2;22), the pressure sensitive transfer layer (3) comprising at least a pressure sensitive adhesive layer (23), wherein the support (2;22) has respective release layers on both sides thereof and wherein the release layer on the transfer layer side contains not less than 1% by weight of inorganic or organic particles having an average particle size of 0.3 to 5 µm providing the support (2;22) with a first coefficient of kinetic friction on the transfer layer side of the support (2;22) against a surface of an object receiving the transfer (13), in particular a paper sheet, and a second coefficient of kinetic friction on the rear side of the support (2;22) against a head member of a transfer tool (12) comprising a polyacetal, wherein the first coefficient of kinetic friction being larger than the second coefficient of kinetic friction, and the difference between the first coefficient of kinetic friction and the second coefficient of kinetic friction being not less than 0.01. The pressure sensitive transfer tape (1;21) according to Claim 1, wherein the pressure sensitive transfer layer (3) has a laminated structure comprising a masking layer and a pressure sensitive adhesive layer (23) laminated in this order from the support side. The pressure sensitive transfer tape (1;21) according to Claim 1, wherein the pressure sensitive transfer layer (3) comprises the pressure sensitive adhesive layer (23) alone. The pressure sensitive transfer tape (1;21) according to Claim 1, wherein the following relationships: Y ≤ 25 µm X/Y ≥ 1 wherein Y denotes a thickness of the support and X a thickness of the pressure sensitive transfer layer (3); are satisfied. The pressure sensitive transfer tape (1;21) according to Claim 7, wherein the pressure sensitive transfer layer (3) has a laminated structure comprising a masking layer and a pressure sensitive adhesive layer (23) laminated in this order from the support side.

Inventors: KATSURO NOBORU, SAKANISHI YUTAKA, TSUNOMORI YUJI, KATSURO, NOBORU, SAKANISHI, YUTAKA, TSUNOMORI, YUJI, Katsuro, Noboru, Tech. Cent. Fujicopian Co., Ltd., Sakanishi, Yutaka, Tec. Cent. Fujicopian Co., Ltd., Tsunomori, Yuji, Tech. Cent. Fujicopian Co., Ltd.
Applicants: FUJI KAGAKU SHIKOGYO, FUJICOPIAN CO., LTD.
Application year: 1999
Main classification: B41J29
IPC codes: B41J29